Re-add `test_max_dust_htlc_exposure`
[rust-lightning] / lightning / src / ln / channel.rs
1 // This file is Copyright its original authors, visible in version control
2 // history.
3 //
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
7 // You may not use this file except in accordance with one or both of these
8 // licenses.
9
10 use bitcoin::blockdata::script::{Script,Builder};
11 use bitcoin::blockdata::transaction::{Transaction, SigHashType};
12 use bitcoin::util::bip143;
13 use bitcoin::consensus::encode;
14
15 use bitcoin::hashes::Hash;
16 use bitcoin::hashes::sha256::Hash as Sha256;
17 use bitcoin::hashes::sha256d::Hash as Sha256d;
18 use bitcoin::hash_types::{Txid, BlockHash};
19
20 use bitcoin::secp256k1::constants::PUBLIC_KEY_SIZE;
21 use bitcoin::secp256k1::key::{PublicKey,SecretKey};
22 use bitcoin::secp256k1::{Secp256k1,Signature};
23 use bitcoin::secp256k1;
24
25 use ln::{PaymentPreimage, PaymentHash};
26 use ln::features::{ChannelFeatures, ChannelTypeFeatures, InitFeatures};
27 use ln::msgs;
28 use ln::msgs::{DecodeError, OptionalField, DataLossProtect};
29 use ln::script::{self, ShutdownScript};
30 use ln::channelmanager::{CounterpartyForwardingInfo, PendingHTLCStatus, HTLCSource, HTLCFailReason, HTLCFailureMsg, PendingHTLCInfo, RAACommitmentOrder, BREAKDOWN_TIMEOUT, MIN_CLTV_EXPIRY_DELTA, MAX_LOCAL_BREAKDOWN_TIMEOUT};
31 use ln::chan_utils::{CounterpartyCommitmentSecrets, TxCreationKeys, HTLCOutputInCommitment, HTLC_SUCCESS_TX_WEIGHT, HTLC_TIMEOUT_TX_WEIGHT, make_funding_redeemscript, ChannelPublicKeys, CommitmentTransaction, HolderCommitmentTransaction, ChannelTransactionParameters, CounterpartyChannelTransactionParameters, MAX_HTLCS, get_commitment_transaction_number_obscure_factor, ClosingTransaction};
32 use ln::chan_utils;
33 use chain::BestBlock;
34 use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
35 use chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateStep, LATENCY_GRACE_PERIOD_BLOCKS};
36 use chain::transaction::{OutPoint, TransactionData};
37 use chain::keysinterface::{Sign, KeysInterface};
38 use util::events::ClosureReason;
39 use util::ser::{Readable, ReadableArgs, Writeable, Writer, VecWriter};
40 use util::logger::Logger;
41 use util::errors::APIError;
42 use util::config::{UserConfig,ChannelConfig};
43 use util::scid_utils::scid_from_parts;
44
45 use io;
46 use prelude::*;
47 use core::{cmp,mem,fmt};
48 use core::ops::Deref;
49 #[cfg(any(test, feature = "fuzztarget", debug_assertions))]
50 use sync::Mutex;
51 use bitcoin::hashes::hex::ToHex;
52
53 #[cfg(test)]
54 pub struct ChannelValueStat {
55         pub value_to_self_msat: u64,
56         pub channel_value_msat: u64,
57         pub channel_reserve_msat: u64,
58         pub pending_outbound_htlcs_amount_msat: u64,
59         pub pending_inbound_htlcs_amount_msat: u64,
60         pub holding_cell_outbound_amount_msat: u64,
61         pub counterparty_max_htlc_value_in_flight_msat: u64, // outgoing
62         pub counterparty_dust_limit_msat: u64,
63 }
64
65 #[derive(Debug, Clone, Copy, PartialEq)]
66 enum FeeUpdateState {
67         // Inbound states mirroring InboundHTLCState
68         RemoteAnnounced,
69         AwaitingRemoteRevokeToAnnounce,
70         // Note that we do not have a AwaitingAnnouncedRemoteRevoke variant here as it is universally
71         // handled the same as `Committed`, with the only exception in `InboundHTLCState` being the
72         // distinction of when we allow ourselves to forward the HTLC. Because we aren't "forwarding"
73         // the fee update anywhere, we can simply consider the fee update `Committed` immediately
74         // instead of setting it to AwaitingAnnouncedRemoteRevoke.
75
76         // Outbound state can only be `LocalAnnounced` or `Committed`
77         Outbound,
78 }
79
80 enum InboundHTLCRemovalReason {
81         FailRelay(msgs::OnionErrorPacket),
82         FailMalformed(([u8; 32], u16)),
83         Fulfill(PaymentPreimage),
84 }
85
86 enum InboundHTLCState {
87         /// Offered by remote, to be included in next local commitment tx. I.e., the remote sent an
88         /// update_add_htlc message for this HTLC.
89         RemoteAnnounced(PendingHTLCStatus),
90         /// Included in a received commitment_signed message (implying we've
91         /// revoke_and_ack'd it), but the remote hasn't yet revoked their previous
92         /// state (see the example below). We have not yet included this HTLC in a
93         /// commitment_signed message because we are waiting on the remote's
94         /// aforementioned state revocation. One reason this missing remote RAA
95         /// (revoke_and_ack) blocks us from constructing a commitment_signed message
96         /// is because every time we create a new "state", i.e. every time we sign a
97         /// new commitment tx (see [BOLT #2]), we need a new per_commitment_point,
98         /// which are provided one-at-a-time in each RAA. E.g., the last RAA they
99         /// sent provided the per_commitment_point for our current commitment tx.
100         /// The other reason we should not send a commitment_signed without their RAA
101         /// is because their RAA serves to ACK our previous commitment_signed.
102         ///
103         /// Here's an example of how an HTLC could come to be in this state:
104         /// remote --> update_add_htlc(prev_htlc)   --> local
105         /// remote --> commitment_signed(prev_htlc) --> local
106         /// remote <-- revoke_and_ack               <-- local
107         /// remote <-- commitment_signed(prev_htlc) <-- local
108         /// [note that here, the remote does not respond with a RAA]
109         /// remote --> update_add_htlc(this_htlc)   --> local
110         /// remote --> commitment_signed(prev_htlc, this_htlc) --> local
111         /// Now `this_htlc` will be assigned this state. It's unable to be officially
112         /// accepted, i.e. included in a commitment_signed, because we're missing the
113         /// RAA that provides our next per_commitment_point. The per_commitment_point
114         /// is used to derive commitment keys, which are used to construct the
115         /// signatures in a commitment_signed message.
116         /// Implies AwaitingRemoteRevoke.
117         ///
118         /// [BOLT #2]: https://github.com/lightningnetwork/lightning-rfc/blob/master/02-peer-protocol.md
119         AwaitingRemoteRevokeToAnnounce(PendingHTLCStatus),
120         /// Included in a received commitment_signed message (implying we've revoke_and_ack'd it).
121         /// We have also included this HTLC in our latest commitment_signed and are now just waiting
122         /// on the remote's revoke_and_ack to make this HTLC an irrevocable part of the state of the
123         /// channel (before it can then get forwarded and/or removed).
124         /// Implies AwaitingRemoteRevoke.
125         AwaitingAnnouncedRemoteRevoke(PendingHTLCStatus),
126         Committed,
127         /// Removed by us and a new commitment_signed was sent (if we were AwaitingRemoteRevoke when we
128         /// created it we would have put it in the holding cell instead). When they next revoke_and_ack
129         /// we'll drop it.
130         /// Note that we have to keep an eye on the HTLC until we've received a broadcastable
131         /// commitment transaction without it as otherwise we'll have to force-close the channel to
132         /// claim it before the timeout (obviously doesn't apply to revoked HTLCs that we can't claim
133         /// anyway). That said, ChannelMonitor does this for us (see
134         /// ChannelMonitor::should_broadcast_holder_commitment_txn) so we actually remove the HTLC from
135         /// our own local state before then, once we're sure that the next commitment_signed and
136         /// ChannelMonitor::provide_latest_local_commitment_tx will not include this HTLC.
137         LocalRemoved(InboundHTLCRemovalReason),
138 }
139
140 struct InboundHTLCOutput {
141         htlc_id: u64,
142         amount_msat: u64,
143         cltv_expiry: u32,
144         payment_hash: PaymentHash,
145         state: InboundHTLCState,
146 }
147
148 enum OutboundHTLCState {
149         /// Added by us and included in a commitment_signed (if we were AwaitingRemoteRevoke when we
150         /// created it we would have put it in the holding cell instead). When they next revoke_and_ack
151         /// we will promote to Committed (note that they may not accept it until the next time we
152         /// revoke, but we don't really care about that:
153         ///  * they've revoked, so worst case we can announce an old state and get our (option on)
154         ///    money back (though we won't), and,
155         ///  * we'll send them a revoke when they send a commitment_signed, and since only they're
156         ///    allowed to remove it, the "can only be removed once committed on both sides" requirement
157         ///    doesn't matter to us and it's up to them to enforce it, worst-case they jump ahead but
158         ///    we'll never get out of sync).
159         /// Note that we Box the OnionPacket as it's rather large and we don't want to blow up
160         /// OutboundHTLCOutput's size just for a temporary bit
161         LocalAnnounced(Box<msgs::OnionPacket>),
162         Committed,
163         /// Remote removed this (outbound) HTLC. We're waiting on their commitment_signed to finalize
164         /// the change (though they'll need to revoke before we fail the payment).
165         RemoteRemoved(Option<HTLCFailReason>),
166         /// Remote removed this and sent a commitment_signed (implying we've revoke_and_ack'ed it), but
167         /// the remote side hasn't yet revoked their previous state, which we need them to do before we
168         /// can do any backwards failing. Implies AwaitingRemoteRevoke.
169         /// We also have not yet removed this HTLC in a commitment_signed message, and are waiting on a
170         /// remote revoke_and_ack on a previous state before we can do so.
171         AwaitingRemoteRevokeToRemove(Option<HTLCFailReason>),
172         /// Remote removed this and sent a commitment_signed (implying we've revoke_and_ack'ed it), but
173         /// the remote side hasn't yet revoked their previous state, which we need them to do before we
174         /// can do any backwards failing. Implies AwaitingRemoteRevoke.
175         /// We have removed this HTLC in our latest commitment_signed and are now just waiting on a
176         /// revoke_and_ack to drop completely.
177         AwaitingRemovedRemoteRevoke(Option<HTLCFailReason>),
178 }
179
180 struct OutboundHTLCOutput {
181         htlc_id: u64,
182         amount_msat: u64,
183         cltv_expiry: u32,
184         payment_hash: PaymentHash,
185         state: OutboundHTLCState,
186         source: HTLCSource,
187 }
188
189 /// See AwaitingRemoteRevoke ChannelState for more info
190 enum HTLCUpdateAwaitingACK {
191         AddHTLC { // TODO: Time out if we're getting close to cltv_expiry
192                 // always outbound
193                 amount_msat: u64,
194                 cltv_expiry: u32,
195                 payment_hash: PaymentHash,
196                 source: HTLCSource,
197                 onion_routing_packet: msgs::OnionPacket,
198         },
199         ClaimHTLC {
200                 payment_preimage: PaymentPreimage,
201                 htlc_id: u64,
202         },
203         FailHTLC {
204                 htlc_id: u64,
205                 err_packet: msgs::OnionErrorPacket,
206         },
207 }
208
209 /// There are a few "states" and then a number of flags which can be applied:
210 /// We first move through init with OurInitSent -> TheirInitSent -> FundingCreated -> FundingSent.
211 /// TheirFundingLocked and OurFundingLocked then get set on FundingSent, and when both are set we
212 /// move on to ChannelFunded.
213 /// Note that PeerDisconnected can be set on both ChannelFunded and FundingSent.
214 /// ChannelFunded can then get all remaining flags set on it, until we finish shutdown, then we
215 /// move on to ShutdownComplete, at which point most calls into this channel are disallowed.
216 enum ChannelState {
217         /// Implies we have (or are prepared to) send our open_channel/accept_channel message
218         OurInitSent = 1 << 0,
219         /// Implies we have received their open_channel/accept_channel message
220         TheirInitSent = 1 << 1,
221         /// We have sent funding_created and are awaiting a funding_signed to advance to FundingSent.
222         /// Note that this is nonsense for an inbound channel as we immediately generate funding_signed
223         /// upon receipt of funding_created, so simply skip this state.
224         FundingCreated = 4,
225         /// Set when we have received/sent funding_created and funding_signed and are thus now waiting
226         /// on the funding transaction to confirm. The FundingLocked flags are set to indicate when we
227         /// and our counterparty consider the funding transaction confirmed.
228         FundingSent = 8,
229         /// Flag which can be set on FundingSent to indicate they sent us a funding_locked message.
230         /// Once both TheirFundingLocked and OurFundingLocked are set, state moves on to ChannelFunded.
231         TheirFundingLocked = 1 << 4,
232         /// Flag which can be set on FundingSent to indicate we sent them a funding_locked message.
233         /// Once both TheirFundingLocked and OurFundingLocked are set, state moves on to ChannelFunded.
234         OurFundingLocked = 1 << 5,
235         ChannelFunded = 64,
236         /// Flag which is set on ChannelFunded and FundingSent indicating remote side is considered
237         /// "disconnected" and no updates are allowed until after we've done a channel_reestablish
238         /// dance.
239         PeerDisconnected = 1 << 7,
240         /// Flag which is set on ChannelFunded, FundingCreated, and FundingSent indicating the user has
241         /// told us they failed to update our ChannelMonitor somewhere and we should pause sending any
242         /// outbound messages until they've managed to do so.
243         MonitorUpdateFailed = 1 << 8,
244         /// Flag which implies that we have sent a commitment_signed but are awaiting the responding
245         /// revoke_and_ack message. During this time period, we can't generate new commitment_signed
246         /// messages as then we will be unable to determine which HTLCs they included in their
247         /// revoke_and_ack implicit ACK, so instead we have to hold them away temporarily to be sent
248         /// later.
249         /// Flag is set on ChannelFunded.
250         AwaitingRemoteRevoke = 1 << 9,
251         /// Flag which is set on ChannelFunded or FundingSent after receiving a shutdown message from
252         /// the remote end. If set, they may not add any new HTLCs to the channel, and we are expected
253         /// to respond with our own shutdown message when possible.
254         RemoteShutdownSent = 1 << 10,
255         /// Flag which is set on ChannelFunded or FundingSent after sending a shutdown message. At this
256         /// point, we may not add any new HTLCs to the channel.
257         LocalShutdownSent = 1 << 11,
258         /// We've successfully negotiated a closing_signed dance. At this point ChannelManager is about
259         /// to drop us, but we store this anyway.
260         ShutdownComplete = 4096,
261 }
262 const BOTH_SIDES_SHUTDOWN_MASK: u32 = ChannelState::LocalShutdownSent as u32 | ChannelState::RemoteShutdownSent as u32;
263 const MULTI_STATE_FLAGS: u32 = BOTH_SIDES_SHUTDOWN_MASK | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32;
264
265 pub const INITIAL_COMMITMENT_NUMBER: u64 = (1 << 48) - 1;
266
267 /// The "channel disabled" bit in channel_update must be set based on whether we are connected to
268 /// our counterparty or not. However, we don't want to announce updates right away to avoid
269 /// spamming the network with updates if the connection is flapping. Instead, we "stage" updates to
270 /// our channel_update message and track the current state here.
271 /// See implementation at [`super::channelmanager::ChannelManager::timer_tick_occurred`].
272 #[derive(Clone, Copy, PartialEq)]
273 pub(super) enum ChannelUpdateStatus {
274         /// We've announced the channel as enabled and are connected to our peer.
275         Enabled,
276         /// Our channel is no longer live, but we haven't announced the channel as disabled yet.
277         DisabledStaged,
278         /// Our channel is live again, but we haven't announced the channel as enabled yet.
279         EnabledStaged,
280         /// We've announced the channel as disabled.
281         Disabled,
282 }
283
284 /// An enum indicating whether the local or remote side offered a given HTLC.
285 enum HTLCInitiator {
286         LocalOffered,
287         RemoteOffered,
288 }
289
290 /// An enum gathering stats on pending HTLCs, either inbound or outbound side.
291 struct HTLCStats {
292         pending_htlcs: u32,
293         pending_htlcs_value_msat: u64,
294         on_counterparty_tx_dust_exposure_msat: u64,
295         on_holder_tx_dust_exposure_msat: u64,
296         holding_cell_msat: u64,
297 }
298
299 /// Used when calculating whether we or the remote can afford an additional HTLC.
300 struct HTLCCandidate {
301         amount_msat: u64,
302         origin: HTLCInitiator,
303 }
304
305 impl HTLCCandidate {
306         fn new(amount_msat: u64, origin: HTLCInitiator) -> Self {
307                 Self {
308                         amount_msat,
309                         origin,
310                 }
311         }
312 }
313
314 /// A return value enum for get_update_fulfill_htlc. See UpdateFulfillCommitFetch variants for
315 /// description
316 enum UpdateFulfillFetch {
317         NewClaim {
318                 monitor_update: ChannelMonitorUpdate,
319                 htlc_value_msat: u64,
320                 msg: Option<msgs::UpdateFulfillHTLC>,
321         },
322         DuplicateClaim {},
323 }
324
325 /// The return type of get_update_fulfill_htlc_and_commit.
326 pub enum UpdateFulfillCommitFetch {
327         /// Indicates the HTLC fulfill is new, and either generated an update_fulfill message, placed
328         /// it in the holding cell, or re-generated the update_fulfill message after the same claim was
329         /// previously placed in the holding cell (and has since been removed).
330         NewClaim {
331                 /// The ChannelMonitorUpdate which places the new payment preimage in the channel monitor
332                 monitor_update: ChannelMonitorUpdate,
333                 /// The value of the HTLC which was claimed, in msat.
334                 htlc_value_msat: u64,
335                 /// The update_fulfill message and commitment_signed message (if the claim was not placed
336                 /// in the holding cell).
337                 msgs: Option<(msgs::UpdateFulfillHTLC, msgs::CommitmentSigned)>,
338         },
339         /// Indicates the HTLC fulfill is duplicative and already existed either in the holding cell
340         /// or has been forgotten (presumably previously claimed).
341         DuplicateClaim {},
342 }
343
344 /// The return value of `revoke_and_ack` on success, primarily updates to other channels or HTLC
345 /// state.
346 pub(super) struct RAAUpdates {
347         pub commitment_update: Option<msgs::CommitmentUpdate>,
348         pub accepted_htlcs: Vec<(PendingHTLCInfo, u64)>,
349         pub failed_htlcs: Vec<(HTLCSource, PaymentHash, HTLCFailReason)>,
350         pub finalized_claimed_htlcs: Vec<HTLCSource>,
351         pub monitor_update: ChannelMonitorUpdate,
352         pub holding_cell_failed_htlcs: Vec<(HTLCSource, PaymentHash)>,
353 }
354
355 /// The return value of `monitor_updating_restored`
356 pub(super) struct MonitorRestoreUpdates {
357         pub raa: Option<msgs::RevokeAndACK>,
358         pub commitment_update: Option<msgs::CommitmentUpdate>,
359         pub order: RAACommitmentOrder,
360         pub accepted_htlcs: Vec<(PendingHTLCInfo, u64)>,
361         pub failed_htlcs: Vec<(HTLCSource, PaymentHash, HTLCFailReason)>,
362         pub finalized_claimed_htlcs: Vec<HTLCSource>,
363         pub funding_broadcastable: Option<Transaction>,
364         pub funding_locked: Option<msgs::FundingLocked>,
365 }
366
367 /// If the majority of the channels funds are to the fundee and the initiator holds only just
368 /// enough funds to cover their reserve value, channels are at risk of getting "stuck". Because the
369 /// initiator controls the feerate, if they then go to increase the channel fee, they may have no
370 /// balance but the fundee is unable to send a payment as the increase in fee more than drains
371 /// their reserve value. Thus, neither side can send a new HTLC and the channel becomes useless.
372 /// Thus, before sending an HTLC when we are the initiator, we check that the feerate can increase
373 /// by this multiple without hitting this case, before sending.
374 /// This multiple is effectively the maximum feerate "jump" we expect until more HTLCs flow over
375 /// the channel. Sadly, there isn't really a good number for this - if we expect to have no new
376 /// HTLCs for days we may need this to suffice for feerate increases across days, but that may
377 /// leave the channel less usable as we hold a bigger reserve.
378 #[cfg(fuzzing)]
379 pub const FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE: u64 = 2;
380 #[cfg(not(fuzzing))]
381 const FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE: u64 = 2;
382
383 /// If we fail to see a funding transaction confirmed on-chain within this many blocks after the
384 /// channel creation on an inbound channel, we simply force-close and move on.
385 /// This constant is the one suggested in BOLT 2.
386 pub(crate) const FUNDING_CONF_DEADLINE_BLOCKS: u32 = 2016;
387
388 /// In case of a concurrent update_add_htlc proposed by our counterparty, we might
389 /// not have enough balance value remaining to cover the onchain cost of this new
390 /// HTLC weight. If this happens, our counterparty fails the reception of our
391 /// commitment_signed including this new HTLC due to infringement on the channel
392 /// reserve.
393 /// To prevent this case, we compute our outbound update_fee with an HTLC buffer of
394 /// size 2. However, if the number of concurrent update_add_htlc is higher, this still
395 /// leads to a channel force-close. Ultimately, this is an issue coming from the
396 /// design of LN state machines, allowing asynchronous updates.
397 const CONCURRENT_INBOUND_HTLC_FEE_BUFFER: u32 = 2;
398
399 // TODO: We should refactor this to be an Inbound/OutboundChannel until initial setup handshaking
400 // has been completed, and then turn into a Channel to get compiler-time enforcement of things like
401 // calling channel_id() before we're set up or things like get_outbound_funding_signed on an
402 // inbound channel.
403 //
404 // Holder designates channel data owned for the benefice of the user client.
405 // Counterparty designates channel data owned by the another channel participant entity.
406 pub(super) struct Channel<Signer: Sign> {
407         #[cfg(any(test, feature = "_test_utils"))]
408         pub(crate) config: ChannelConfig,
409         #[cfg(not(any(test, feature = "_test_utils")))]
410         config: ChannelConfig,
411
412         user_id: u64,
413
414         channel_id: [u8; 32],
415         channel_state: u32,
416         secp_ctx: Secp256k1<secp256k1::All>,
417         channel_value_satoshis: u64,
418
419         latest_monitor_update_id: u64,
420
421         holder_signer: Signer,
422         shutdown_scriptpubkey: Option<ShutdownScript>,
423         destination_script: Script,
424
425         // Our commitment numbers start at 2^48-1 and count down, whereas the ones used in transaction
426         // generation start at 0 and count up...this simplifies some parts of implementation at the
427         // cost of others, but should really just be changed.
428
429         cur_holder_commitment_transaction_number: u64,
430         cur_counterparty_commitment_transaction_number: u64,
431         value_to_self_msat: u64, // Excluding all pending_htlcs, excluding fees
432         pending_inbound_htlcs: Vec<InboundHTLCOutput>,
433         pending_outbound_htlcs: Vec<OutboundHTLCOutput>,
434         holding_cell_htlc_updates: Vec<HTLCUpdateAwaitingACK>,
435
436         /// When resending CS/RAA messages on channel monitor restoration or on reconnect, we always
437         /// need to ensure we resend them in the order we originally generated them. Note that because
438         /// there can only ever be one in-flight CS and/or one in-flight RAA at any time, it is
439         /// sufficient to simply set this to the opposite of any message we are generating as we
440         /// generate it. ie when we generate a CS, we set this to RAAFirst as, if there is a pending
441         /// in-flight RAA to resend, it will have been the first thing we generated, and thus we should
442         /// send it first.
443         resend_order: RAACommitmentOrder,
444
445         monitor_pending_funding_locked: bool,
446         monitor_pending_revoke_and_ack: bool,
447         monitor_pending_commitment_signed: bool,
448         monitor_pending_forwards: Vec<(PendingHTLCInfo, u64)>,
449         monitor_pending_failures: Vec<(HTLCSource, PaymentHash, HTLCFailReason)>,
450         monitor_pending_finalized_fulfills: Vec<HTLCSource>,
451
452         // pending_update_fee is filled when sending and receiving update_fee.
453         //
454         // Because it follows the same commitment flow as HTLCs, `FeeUpdateState` is either `Outbound`
455         // or matches a subset of the `InboundHTLCOutput` variants. It is then updated/used when
456         // generating new commitment transactions with exactly the same criteria as inbound/outbound
457         // HTLCs with similar state.
458         pending_update_fee: Option<(u32, FeeUpdateState)>,
459         // If a `send_update_fee()` call is made with ChannelState::AwaitingRemoteRevoke set, we place
460         // it here instead of `pending_update_fee` in the same way as we place outbound HTLC updates in
461         // `holding_cell_htlc_updates` instead of `pending_outbound_htlcs`. It is released into
462         // `pending_update_fee` with the same criteria as outbound HTLC updates but can be updated by
463         // further `send_update_fee` calls, dropping the previous holding cell update entirely.
464         holding_cell_update_fee: Option<u32>,
465         next_holder_htlc_id: u64,
466         next_counterparty_htlc_id: u64,
467         update_time_counter: u32,
468         feerate_per_kw: u32,
469
470         #[cfg(debug_assertions)]
471         /// Max to_local and to_remote outputs in a locally-generated commitment transaction
472         holder_max_commitment_tx_output: Mutex<(u64, u64)>,
473         #[cfg(debug_assertions)]
474         /// Max to_local and to_remote outputs in a remote-generated commitment transaction
475         counterparty_max_commitment_tx_output: Mutex<(u64, u64)>,
476
477         last_sent_closing_fee: Option<(u64, Signature)>, // (fee, holder_sig)
478         target_closing_feerate_sats_per_kw: Option<u32>,
479
480         /// If our counterparty sent us a closing_signed while we were waiting for a `ChannelMonitor`
481         /// update, we need to delay processing it until later. We do that here by simply storing the
482         /// closing_signed message and handling it in `maybe_propose_closing_signed`.
483         pending_counterparty_closing_signed: Option<msgs::ClosingSigned>,
484
485         /// The minimum and maximum absolute fee, in satoshis, we are willing to place on the closing
486         /// transaction. These are set once we reach `closing_negotiation_ready`.
487         #[cfg(test)]
488         pub(crate) closing_fee_limits: Option<(u64, u64)>,
489         #[cfg(not(test))]
490         closing_fee_limits: Option<(u64, u64)>,
491
492         /// The hash of the block in which the funding transaction was included.
493         funding_tx_confirmed_in: Option<BlockHash>,
494         funding_tx_confirmation_height: u32,
495         short_channel_id: Option<u64>,
496         /// Either the height at which this channel was created or the height at which it was last
497         /// serialized if it was serialized by versions prior to 0.0.103.
498         /// We use this to close if funding is never broadcasted.
499         channel_creation_height: u32,
500
501         counterparty_dust_limit_satoshis: u64,
502         #[cfg(test)]
503         pub(super) holder_dust_limit_satoshis: u64,
504         #[cfg(not(test))]
505         holder_dust_limit_satoshis: u64,
506         #[cfg(test)]
507         pub(super) counterparty_max_htlc_value_in_flight_msat: u64,
508         #[cfg(not(test))]
509         counterparty_max_htlc_value_in_flight_msat: u64,
510         //get_holder_max_htlc_value_in_flight_msat(): u64,
511         /// minimum channel reserve for self to maintain - set by them.
512         counterparty_selected_channel_reserve_satoshis: Option<u64>,
513         // get_holder_selected_channel_reserve_satoshis(channel_value_sats: u64): u64
514         counterparty_htlc_minimum_msat: u64,
515         holder_htlc_minimum_msat: u64,
516         #[cfg(test)]
517         pub counterparty_max_accepted_htlcs: u16,
518         #[cfg(not(test))]
519         counterparty_max_accepted_htlcs: u16,
520         //implied by OUR_MAX_HTLCS: max_accepted_htlcs: u16,
521         minimum_depth: Option<u32>,
522
523         counterparty_forwarding_info: Option<CounterpartyForwardingInfo>,
524
525         pub(crate) channel_transaction_parameters: ChannelTransactionParameters,
526         funding_transaction: Option<Transaction>,
527
528         counterparty_cur_commitment_point: Option<PublicKey>,
529         counterparty_prev_commitment_point: Option<PublicKey>,
530         counterparty_node_id: PublicKey,
531
532         counterparty_shutdown_scriptpubkey: Option<Script>,
533
534         commitment_secrets: CounterpartyCommitmentSecrets,
535
536         channel_update_status: ChannelUpdateStatus,
537         /// Once we reach `closing_negotiation_ready`, we set this, indicating if closing_signed does
538         /// not complete within a single timer tick (one minute), we should force-close the channel.
539         /// This prevents us from keeping unusable channels around forever if our counterparty wishes
540         /// to DoS us.
541         /// Note that this field is reset to false on deserialization to give us a chance to connect to
542         /// our peer and start the closing_signed negotiation fresh.
543         closing_signed_in_flight: bool,
544
545         /// Our counterparty's channel_announcement signatures provided in announcement_signatures.
546         /// This can be used to rebroadcast the channel_announcement message later.
547         announcement_sigs: Option<(Signature, Signature)>,
548
549         // We save these values so we can make sure `next_local_commit_tx_fee_msat` and
550         // `next_remote_commit_tx_fee_msat` properly predict what the next commitment transaction fee will
551         // be, by comparing the cached values to the fee of the tranaction generated by
552         // `build_commitment_transaction`.
553         #[cfg(any(test, feature = "fuzztarget"))]
554         next_local_commitment_tx_fee_info_cached: Mutex<Option<CommitmentTxInfoCached>>,
555         #[cfg(any(test, feature = "fuzztarget"))]
556         next_remote_commitment_tx_fee_info_cached: Mutex<Option<CommitmentTxInfoCached>>,
557
558         /// lnd has a long-standing bug where, upon reconnection, if the channel is not yet confirmed
559         /// they will not send a channel_reestablish until the channel locks in. Then, they will send a
560         /// funding_locked *before* sending the channel_reestablish (which is clearly a violation of
561         /// the BOLT specs). We copy c-lightning's workaround here and simply store the funding_locked
562         /// message until we receive a channel_reestablish.
563         ///
564         /// See-also <https://github.com/lightningnetwork/lnd/issues/4006>
565         pub workaround_lnd_bug_4006: Option<msgs::FundingLocked>,
566
567         #[cfg(any(test, feature = "fuzztarget"))]
568         // When we receive an HTLC fulfill on an outbound path, we may immediately fulfill the
569         // corresponding HTLC on the inbound path. If, then, the outbound path channel is
570         // disconnected and reconnected (before we've exchange commitment_signed and revoke_and_ack
571         // messages), they may re-broadcast their update_fulfill_htlc, causing a duplicate claim. This
572         // is fine, but as a sanity check in our failure to generate the second claim, we check here
573         // that the original was a claim, and that we aren't now trying to fulfill a failed HTLC.
574         historical_inbound_htlc_fulfills: HashSet<u64>,
575
576         /// This channel's type, as negotiated during channel open
577         channel_type: ChannelTypeFeatures,
578 }
579
580 #[cfg(any(test, feature = "fuzztarget"))]
581 struct CommitmentTxInfoCached {
582         fee: u64,
583         total_pending_htlcs: usize,
584         next_holder_htlc_id: u64,
585         next_counterparty_htlc_id: u64,
586         feerate: u32,
587 }
588
589 pub const OUR_MAX_HTLCS: u16 = 50; //TODO
590
591 #[cfg(not(test))]
592 const COMMITMENT_TX_BASE_WEIGHT: u64 = 724;
593 #[cfg(test)]
594 pub const COMMITMENT_TX_BASE_WEIGHT: u64 = 724;
595 #[cfg(not(test))]
596 const COMMITMENT_TX_WEIGHT_PER_HTLC: u64 = 172;
597 #[cfg(test)]
598 pub const COMMITMENT_TX_WEIGHT_PER_HTLC: u64 = 172;
599
600 pub const ANCHOR_OUTPUT_VALUE_SATOSHI: u64 = 330;
601
602 /// Maximum `funding_satoshis` value, according to the BOLT #2 specification
603 /// it's 2^24.
604 pub const MAX_FUNDING_SATOSHIS: u64 = 1 << 24;
605
606 /// The maximum network dust limit for standard script formats. This currently represents the
607 /// minimum output value for a P2SH output before Bitcoin Core 22 considers the entire
608 /// transaction non-standard and thus refuses to relay it.
609 /// We also use this as the maximum counterparty `dust_limit_satoshis` allowed, given many
610 /// implementations use this value for their dust limit today.
611 pub const MAX_STD_OUTPUT_DUST_LIMIT_SATOSHIS: u64 = 546;
612
613 /// The maximum channel dust limit we will accept from our counterparty.
614 pub const MAX_CHAN_DUST_LIMIT_SATOSHIS: u64 = MAX_STD_OUTPUT_DUST_LIMIT_SATOSHIS;
615
616 /// The dust limit is used for both the commitment transaction outputs as well as the closing
617 /// transactions. For cooperative closing transactions, we require segwit outputs, though accept
618 /// *any* segwit scripts, which are allowed to be up to 42 bytes in length.
619 /// In order to avoid having to concern ourselves with standardness during the closing process, we
620 /// simply require our counterparty to use a dust limit which will leave any segwit output
621 /// standard.
622 /// See https://github.com/lightningnetwork/lightning-rfc/issues/905 for more details.
623 pub const MIN_CHAN_DUST_LIMIT_SATOSHIS: u64 = 354;
624
625 /// Used to return a simple Error back to ChannelManager. Will get converted to a
626 /// msgs::ErrorAction::SendErrorMessage or msgs::ErrorAction::IgnoreError as appropriate with our
627 /// channel_id in ChannelManager.
628 pub(super) enum ChannelError {
629         Ignore(String),
630         Warn(String),
631         Close(String),
632         CloseDelayBroadcast(String),
633 }
634
635 impl fmt::Debug for ChannelError {
636         fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
637                 match self {
638                         &ChannelError::Ignore(ref e) => write!(f, "Ignore : {}", e),
639                         &ChannelError::Warn(ref e) => write!(f, "Warn : {}", e),
640                         &ChannelError::Close(ref e) => write!(f, "Close : {}", e),
641                         &ChannelError::CloseDelayBroadcast(ref e) => write!(f, "CloseDelayBroadcast : {}", e)
642                 }
643         }
644 }
645
646 macro_rules! secp_check {
647         ($res: expr, $err: expr) => {
648                 match $res {
649                         Ok(thing) => thing,
650                         Err(_) => return Err(ChannelError::Close($err)),
651                 }
652         };
653 }
654
655 impl<Signer: Sign> Channel<Signer> {
656         // Convert constants + channel value to limits:
657         fn get_holder_max_htlc_value_in_flight_msat(channel_value_satoshis: u64) -> u64 {
658                 channel_value_satoshis * 1000 / 10 //TODO
659         }
660
661         /// Returns a minimum channel reserve value the remote needs to maintain,
662         /// required by us.
663         ///
664         /// Guaranteed to return a value no larger than channel_value_satoshis
665         pub(crate) fn get_holder_selected_channel_reserve_satoshis(channel_value_satoshis: u64) -> u64 {
666                 let (q, _) = channel_value_satoshis.overflowing_div(100);
667                 cmp::min(channel_value_satoshis, cmp::max(q, 1000)) //TODO
668         }
669
670         // Constructors:
671         pub fn new_outbound<K: Deref, F: Deref>(
672                 fee_estimator: &F, keys_provider: &K, counterparty_node_id: PublicKey, their_features: &InitFeatures,
673                 channel_value_satoshis: u64, push_msat: u64, user_id: u64, config: &UserConfig, current_chain_height: u32
674         ) -> Result<Channel<Signer>, APIError>
675         where K::Target: KeysInterface<Signer = Signer>,
676               F::Target: FeeEstimator,
677         {
678                 let holder_selected_contest_delay = config.own_channel_config.our_to_self_delay;
679                 let holder_signer = keys_provider.get_channel_signer(false, channel_value_satoshis);
680                 let pubkeys = holder_signer.pubkeys().clone();
681
682                 if channel_value_satoshis >= MAX_FUNDING_SATOSHIS {
683                         return Err(APIError::APIMisuseError{err: format!("funding_value must be smaller than {}, it was {}", MAX_FUNDING_SATOSHIS, channel_value_satoshis)});
684                 }
685                 let channel_value_msat = channel_value_satoshis * 1000;
686                 if push_msat > channel_value_msat {
687                         return Err(APIError::APIMisuseError { err: format!("Push value ({}) was larger than channel_value ({})", push_msat, channel_value_msat) });
688                 }
689                 if holder_selected_contest_delay < BREAKDOWN_TIMEOUT {
690                         return Err(APIError::APIMisuseError {err: format!("Configured with an unreasonable our_to_self_delay ({}) putting user funds at risks", holder_selected_contest_delay)});
691                 }
692                 let holder_selected_channel_reserve_satoshis = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(channel_value_satoshis);
693                 if holder_selected_channel_reserve_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
694                         return Err(APIError::APIMisuseError { err: format!("Holder selected channel  reserve below implemention limit dust_limit_satoshis {}", holder_selected_channel_reserve_satoshis) });
695                 }
696
697                 let feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
698
699                 let mut secp_ctx = Secp256k1::new();
700                 secp_ctx.seeded_randomize(&keys_provider.get_secure_random_bytes());
701
702                 let shutdown_scriptpubkey = if config.channel_options.commit_upfront_shutdown_pubkey {
703                         Some(keys_provider.get_shutdown_scriptpubkey())
704                 } else { None };
705
706                 if let Some(shutdown_scriptpubkey) = &shutdown_scriptpubkey {
707                         if !shutdown_scriptpubkey.is_compatible(&their_features) {
708                                 return Err(APIError::IncompatibleShutdownScript { script: shutdown_scriptpubkey.clone() });
709                         }
710                 }
711
712                 Ok(Channel {
713                         user_id,
714                         config: config.channel_options.clone(),
715
716                         channel_id: keys_provider.get_secure_random_bytes(),
717                         channel_state: ChannelState::OurInitSent as u32,
718                         secp_ctx,
719                         channel_value_satoshis,
720
721                         latest_monitor_update_id: 0,
722
723                         holder_signer,
724                         shutdown_scriptpubkey,
725                         destination_script: keys_provider.get_destination_script(),
726
727                         cur_holder_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
728                         cur_counterparty_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
729                         value_to_self_msat: channel_value_satoshis * 1000 - push_msat,
730
731                         pending_inbound_htlcs: Vec::new(),
732                         pending_outbound_htlcs: Vec::new(),
733                         holding_cell_htlc_updates: Vec::new(),
734                         pending_update_fee: None,
735                         holding_cell_update_fee: None,
736                         next_holder_htlc_id: 0,
737                         next_counterparty_htlc_id: 0,
738                         update_time_counter: 1,
739
740                         resend_order: RAACommitmentOrder::CommitmentFirst,
741
742                         monitor_pending_funding_locked: false,
743                         monitor_pending_revoke_and_ack: false,
744                         monitor_pending_commitment_signed: false,
745                         monitor_pending_forwards: Vec::new(),
746                         monitor_pending_failures: Vec::new(),
747                         monitor_pending_finalized_fulfills: Vec::new(),
748
749                         #[cfg(debug_assertions)]
750                         holder_max_commitment_tx_output: Mutex::new((channel_value_satoshis * 1000 - push_msat, push_msat)),
751                         #[cfg(debug_assertions)]
752                         counterparty_max_commitment_tx_output: Mutex::new((channel_value_satoshis * 1000 - push_msat, push_msat)),
753
754                         last_sent_closing_fee: None,
755                         pending_counterparty_closing_signed: None,
756                         closing_fee_limits: None,
757                         target_closing_feerate_sats_per_kw: None,
758
759                         funding_tx_confirmed_in: None,
760                         funding_tx_confirmation_height: 0,
761                         short_channel_id: None,
762                         channel_creation_height: current_chain_height,
763
764                         feerate_per_kw: feerate,
765                         counterparty_dust_limit_satoshis: 0,
766                         holder_dust_limit_satoshis: MIN_CHAN_DUST_LIMIT_SATOSHIS,
767                         counterparty_max_htlc_value_in_flight_msat: 0,
768                         counterparty_selected_channel_reserve_satoshis: None, // Filled in in accept_channel
769                         counterparty_htlc_minimum_msat: 0,
770                         holder_htlc_minimum_msat: if config.own_channel_config.our_htlc_minimum_msat == 0 { 1 } else { config.own_channel_config.our_htlc_minimum_msat },
771                         counterparty_max_accepted_htlcs: 0,
772                         minimum_depth: None, // Filled in in accept_channel
773
774                         counterparty_forwarding_info: None,
775
776                         channel_transaction_parameters: ChannelTransactionParameters {
777                                 holder_pubkeys: pubkeys,
778                                 holder_selected_contest_delay: config.own_channel_config.our_to_self_delay,
779                                 is_outbound_from_holder: true,
780                                 counterparty_parameters: None,
781                                 funding_outpoint: None
782                         },
783                         funding_transaction: None,
784
785                         counterparty_cur_commitment_point: None,
786                         counterparty_prev_commitment_point: None,
787                         counterparty_node_id,
788
789                         counterparty_shutdown_scriptpubkey: None,
790
791                         commitment_secrets: CounterpartyCommitmentSecrets::new(),
792
793                         channel_update_status: ChannelUpdateStatus::Enabled,
794                         closing_signed_in_flight: false,
795
796                         announcement_sigs: None,
797
798                         #[cfg(any(test, feature = "fuzztarget"))]
799                         next_local_commitment_tx_fee_info_cached: Mutex::new(None),
800                         #[cfg(any(test, feature = "fuzztarget"))]
801                         next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
802
803                         workaround_lnd_bug_4006: None,
804
805                         #[cfg(any(test, feature = "fuzztarget"))]
806                         historical_inbound_htlc_fulfills: HashSet::new(),
807
808                         // We currently only actually support one channel type, so don't retry with new types
809                         // on error messages. When we support more we'll need fallback support (assuming we
810                         // want to support old types).
811                         channel_type: ChannelTypeFeatures::only_static_remote_key(),
812                 })
813         }
814
815         fn check_remote_fee<F: Deref>(fee_estimator: &F, feerate_per_kw: u32) -> Result<(), ChannelError>
816                 where F::Target: FeeEstimator
817         {
818                 let lower_limit = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
819                 if feerate_per_kw < lower_limit {
820                         return Err(ChannelError::Close(format!("Peer's feerate much too low. Actual: {}. Our expected lower limit: {}", feerate_per_kw, lower_limit)));
821                 }
822                 // We only bound the fee updates on the upper side to prevent completely absurd feerates,
823                 // always accepting up to 25 sat/vByte or 10x our fee estimator's "High Priority" fee.
824                 // We generally don't care too much if they set the feerate to something very high, but it
825                 // could result in the channel being useless due to everything being dust.
826                 let upper_limit = cmp::max(250 * 25,
827                         fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::HighPriority) as u64 * 10);
828                 if feerate_per_kw as u64 > upper_limit {
829                         return Err(ChannelError::Close(format!("Peer's feerate much too high. Actual: {}. Our expected upper limit: {}", feerate_per_kw, upper_limit)));
830                 }
831                 Ok(())
832         }
833
834         /// Creates a new channel from a remote sides' request for one.
835         /// Assumes chain_hash has already been checked and corresponds with what we expect!
836         pub fn new_from_req<K: Deref, F: Deref>(
837                 fee_estimator: &F, keys_provider: &K, counterparty_node_id: PublicKey, their_features: &InitFeatures,
838                 msg: &msgs::OpenChannel, user_id: u64, config: &UserConfig, current_chain_height: u32
839         ) -> Result<Channel<Signer>, ChannelError>
840                 where K::Target: KeysInterface<Signer = Signer>,
841           F::Target: FeeEstimator
842         {
843                 // First check the channel type is known, failing before we do anything else if we don't
844                 // support this channel type.
845                 let channel_type = if let Some(channel_type) = &msg.channel_type {
846                         if channel_type.supports_any_optional_bits() {
847                                 return Err(ChannelError::Close("Channel Type field contained optional bits - this is not allowed".to_owned()));
848                         }
849                         if *channel_type != ChannelTypeFeatures::only_static_remote_key() {
850                                 return Err(ChannelError::Close("Channel Type was not understood".to_owned()));
851                         }
852                         channel_type.clone()
853                 } else {
854                         ChannelTypeFeatures::from_counterparty_init(&their_features)
855                 };
856                 if !channel_type.supports_static_remote_key() {
857                         return Err(ChannelError::Close("Channel Type was not understood - we require static remote key".to_owned()));
858                 }
859
860                 let holder_signer = keys_provider.get_channel_signer(true, msg.funding_satoshis);
861                 let pubkeys = holder_signer.pubkeys().clone();
862                 let counterparty_pubkeys = ChannelPublicKeys {
863                         funding_pubkey: msg.funding_pubkey,
864                         revocation_basepoint: msg.revocation_basepoint,
865                         payment_point: msg.payment_point,
866                         delayed_payment_basepoint: msg.delayed_payment_basepoint,
867                         htlc_basepoint: msg.htlc_basepoint
868                 };
869                 let mut local_config = (*config).channel_options.clone();
870
871                 if config.own_channel_config.our_to_self_delay < BREAKDOWN_TIMEOUT {
872                         return Err(ChannelError::Close(format!("Configured with an unreasonable our_to_self_delay ({}) putting user funds at risks. It must be greater than {}", config.own_channel_config.our_to_self_delay, BREAKDOWN_TIMEOUT)));
873                 }
874
875                 // Check sanity of message fields:
876                 if msg.funding_satoshis >= MAX_FUNDING_SATOSHIS {
877                         return Err(ChannelError::Close(format!("Funding must be smaller than {}. It was {}", MAX_FUNDING_SATOSHIS, msg.funding_satoshis)));
878                 }
879                 if msg.channel_reserve_satoshis > msg.funding_satoshis {
880                         return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must be not greater than funding_satoshis: {}", msg.channel_reserve_satoshis, msg.funding_satoshis)));
881                 }
882                 let funding_value = (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000;
883                 if msg.push_msat > funding_value {
884                         return Err(ChannelError::Close(format!("push_msat {} was larger than funding value {}", msg.push_msat, funding_value)));
885                 }
886                 if msg.dust_limit_satoshis > msg.funding_satoshis {
887                         return Err(ChannelError::Close(format!("dust_limit_satoshis {} was larger than funding_satoshis {}. Peer never wants payout outputs?", msg.dust_limit_satoshis, msg.funding_satoshis)));
888                 }
889                 if msg.dust_limit_satoshis > msg.channel_reserve_satoshis {
890                         return Err(ChannelError::Close(format!("Bogus; channel reserve ({}) is less than dust limit ({})", msg.channel_reserve_satoshis, msg.dust_limit_satoshis)));
891                 }
892                 let full_channel_value_msat = (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000;
893                 if msg.htlc_minimum_msat >= full_channel_value_msat {
894                         return Err(ChannelError::Close(format!("Minimum htlc value ({}) was larger than full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat)));
895                 }
896                 Channel::<Signer>::check_remote_fee(fee_estimator, msg.feerate_per_kw)?;
897
898                 let max_counterparty_selected_contest_delay = u16::min(config.peer_channel_config_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
899                 if msg.to_self_delay > max_counterparty_selected_contest_delay {
900                         return Err(ChannelError::Close(format!("They wanted our payments to be delayed by a needlessly long period. Upper limit: {}. Actual: {}", max_counterparty_selected_contest_delay, msg.to_self_delay)));
901                 }
902                 if msg.max_accepted_htlcs < 1 {
903                         return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel".to_owned()));
904                 }
905                 if msg.max_accepted_htlcs > MAX_HTLCS {
906                         return Err(ChannelError::Close(format!("max_accepted_htlcs was {}. It must not be larger than {}", msg.max_accepted_htlcs, MAX_HTLCS)));
907                 }
908
909                 // Now check against optional parameters as set by config...
910                 if msg.funding_satoshis < config.peer_channel_config_limits.min_funding_satoshis {
911                         return Err(ChannelError::Close(format!("Funding satoshis ({}) is less than the user specified limit ({})", msg.funding_satoshis, config.peer_channel_config_limits.min_funding_satoshis)));
912                 }
913                 if msg.htlc_minimum_msat > config.peer_channel_config_limits.max_htlc_minimum_msat {
914                         return Err(ChannelError::Close(format!("htlc_minimum_msat ({}) is higher than the user specified limit ({})", msg.htlc_minimum_msat,  config.peer_channel_config_limits.max_htlc_minimum_msat)));
915                 }
916                 if msg.max_htlc_value_in_flight_msat < config.peer_channel_config_limits.min_max_htlc_value_in_flight_msat {
917                         return Err(ChannelError::Close(format!("max_htlc_value_in_flight_msat ({}) is less than the user specified limit ({})", msg.max_htlc_value_in_flight_msat, config.peer_channel_config_limits.min_max_htlc_value_in_flight_msat)));
918                 }
919                 if msg.channel_reserve_satoshis > config.peer_channel_config_limits.max_channel_reserve_satoshis {
920                         return Err(ChannelError::Close(format!("channel_reserve_satoshis ({}) is higher than the user specified limit ({})", msg.channel_reserve_satoshis, config.peer_channel_config_limits.max_channel_reserve_satoshis)));
921                 }
922                 if msg.max_accepted_htlcs < config.peer_channel_config_limits.min_max_accepted_htlcs {
923                         return Err(ChannelError::Close(format!("max_accepted_htlcs ({}) is less than the user specified limit ({})", msg.max_accepted_htlcs, config.peer_channel_config_limits.min_max_accepted_htlcs)));
924                 }
925                 if msg.dust_limit_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
926                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the implementation limit ({})", msg.dust_limit_satoshis, MIN_CHAN_DUST_LIMIT_SATOSHIS)));
927                 }
928                 if msg.dust_limit_satoshis >  MAX_CHAN_DUST_LIMIT_SATOSHIS {
929                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the implementation limit ({})", msg.dust_limit_satoshis, MAX_CHAN_DUST_LIMIT_SATOSHIS)));
930                 }
931
932                 // Convert things into internal flags and prep our state:
933
934                 let announce = if (msg.channel_flags & 1) == 1 { true } else { false };
935                 if config.peer_channel_config_limits.force_announced_channel_preference {
936                         if local_config.announced_channel != announce {
937                                 return Err(ChannelError::Close("Peer tried to open channel but their announcement preference is different from ours".to_owned()));
938                         }
939                 }
940                 // we either accept their preference or the preferences match
941                 local_config.announced_channel = announce;
942
943                 let background_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
944
945                 let holder_selected_channel_reserve_satoshis = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(msg.funding_satoshis);
946                 if holder_selected_channel_reserve_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
947                         return Err(ChannelError::Close(format!("Suitable channel reserve not found. remote_channel_reserve was ({}). dust_limit_satoshis is ({}).", holder_selected_channel_reserve_satoshis, MIN_CHAN_DUST_LIMIT_SATOSHIS)));
948                 }
949                 if msg.channel_reserve_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
950                         return Err(ChannelError::Close(format!("channel_reserve_satoshis ({}) is smaller than our dust limit ({})", msg.channel_reserve_satoshis, MIN_CHAN_DUST_LIMIT_SATOSHIS)));
951                 }
952                 if holder_selected_channel_reserve_satoshis < msg.dust_limit_satoshis {
953                         return Err(ChannelError::Close(format!("Dust limit ({}) too high for the channel reserve we require the remote to keep ({})", msg.dust_limit_satoshis, holder_selected_channel_reserve_satoshis)));
954                 }
955
956                 // check if the funder's amount for the initial commitment tx is sufficient
957                 // for full fee payment
958                 let funders_amount_msat = msg.funding_satoshis * 1000 - msg.push_msat;
959                 let lower_limit = background_feerate as u64 * COMMITMENT_TX_BASE_WEIGHT;
960                 if funders_amount_msat < lower_limit {
961                         return Err(ChannelError::Close(format!("Insufficient funding amount ({}) for initial commitment. Must be at least {}", funders_amount_msat, lower_limit)));
962                 }
963
964                 let to_local_msat = msg.push_msat;
965                 let to_remote_msat = funders_amount_msat - background_feerate as u64 * COMMITMENT_TX_BASE_WEIGHT;
966                 if to_local_msat <= msg.channel_reserve_satoshis * 1000 && to_remote_msat <= holder_selected_channel_reserve_satoshis * 1000 {
967                         return Err(ChannelError::Close("Insufficient funding amount for initial commitment".to_owned()));
968                 }
969
970                 let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() {
971                         match &msg.shutdown_scriptpubkey {
972                                 &OptionalField::Present(ref script) => {
973                                         // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything
974                                         if script.len() == 0 {
975                                                 None
976                                         } else {
977                                                 if !script::is_bolt2_compliant(&script, their_features) {
978                                                         return Err(ChannelError::Close(format!("Peer is signaling upfront_shutdown but has provided an unacceptable scriptpubkey format: {}", script)))
979                                                 }
980                                                 Some(script.clone())
981                                         }
982                                 },
983                                 // Peer is signaling upfront shutdown but don't opt-out with correct mechanism (a.k.a 0-length script). Peer looks buggy, we fail the channel
984                                 &OptionalField::Absent => {
985                                         return Err(ChannelError::Close("Peer is signaling upfront_shutdown but we don't get any script. Use 0-length script to opt-out".to_owned()));
986                                 }
987                         }
988                 } else { None };
989
990                 let shutdown_scriptpubkey = if config.channel_options.commit_upfront_shutdown_pubkey {
991                         Some(keys_provider.get_shutdown_scriptpubkey())
992                 } else { None };
993
994                 if let Some(shutdown_scriptpubkey) = &shutdown_scriptpubkey {
995                         if !shutdown_scriptpubkey.is_compatible(&their_features) {
996                                 return Err(ChannelError::Close(format!("Provided a scriptpubkey format not accepted by peer: {}", shutdown_scriptpubkey)));
997                         }
998                 }
999
1000                 let mut secp_ctx = Secp256k1::new();
1001                 secp_ctx.seeded_randomize(&keys_provider.get_secure_random_bytes());
1002
1003                 let chan = Channel {
1004                         user_id,
1005                         config: local_config,
1006
1007                         channel_id: msg.temporary_channel_id,
1008                         channel_state: (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32),
1009                         secp_ctx,
1010
1011                         latest_monitor_update_id: 0,
1012
1013                         holder_signer,
1014                         shutdown_scriptpubkey,
1015                         destination_script: keys_provider.get_destination_script(),
1016
1017                         cur_holder_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
1018                         cur_counterparty_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
1019                         value_to_self_msat: msg.push_msat,
1020
1021                         pending_inbound_htlcs: Vec::new(),
1022                         pending_outbound_htlcs: Vec::new(),
1023                         holding_cell_htlc_updates: Vec::new(),
1024                         pending_update_fee: None,
1025                         holding_cell_update_fee: None,
1026                         next_holder_htlc_id: 0,
1027                         next_counterparty_htlc_id: 0,
1028                         update_time_counter: 1,
1029
1030                         resend_order: RAACommitmentOrder::CommitmentFirst,
1031
1032                         monitor_pending_funding_locked: false,
1033                         monitor_pending_revoke_and_ack: false,
1034                         monitor_pending_commitment_signed: false,
1035                         monitor_pending_forwards: Vec::new(),
1036                         monitor_pending_failures: Vec::new(),
1037                         monitor_pending_finalized_fulfills: Vec::new(),
1038
1039                         #[cfg(debug_assertions)]
1040                         holder_max_commitment_tx_output: Mutex::new((msg.push_msat, msg.funding_satoshis * 1000 - msg.push_msat)),
1041                         #[cfg(debug_assertions)]
1042                         counterparty_max_commitment_tx_output: Mutex::new((msg.push_msat, msg.funding_satoshis * 1000 - msg.push_msat)),
1043
1044                         last_sent_closing_fee: None,
1045                         pending_counterparty_closing_signed: None,
1046                         closing_fee_limits: None,
1047                         target_closing_feerate_sats_per_kw: None,
1048
1049                         funding_tx_confirmed_in: None,
1050                         funding_tx_confirmation_height: 0,
1051                         short_channel_id: None,
1052                         channel_creation_height: current_chain_height,
1053
1054                         feerate_per_kw: msg.feerate_per_kw,
1055                         channel_value_satoshis: msg.funding_satoshis,
1056                         counterparty_dust_limit_satoshis: msg.dust_limit_satoshis,
1057                         holder_dust_limit_satoshis: MIN_CHAN_DUST_LIMIT_SATOSHIS,
1058                         counterparty_max_htlc_value_in_flight_msat: cmp::min(msg.max_htlc_value_in_flight_msat, msg.funding_satoshis * 1000),
1059                         counterparty_selected_channel_reserve_satoshis: Some(msg.channel_reserve_satoshis),
1060                         counterparty_htlc_minimum_msat: msg.htlc_minimum_msat,
1061                         holder_htlc_minimum_msat: if config.own_channel_config.our_htlc_minimum_msat == 0 { 1 } else { config.own_channel_config.our_htlc_minimum_msat },
1062                         counterparty_max_accepted_htlcs: msg.max_accepted_htlcs,
1063                         minimum_depth: Some(config.own_channel_config.minimum_depth),
1064
1065                         counterparty_forwarding_info: None,
1066
1067                         channel_transaction_parameters: ChannelTransactionParameters {
1068                                 holder_pubkeys: pubkeys,
1069                                 holder_selected_contest_delay: config.own_channel_config.our_to_self_delay,
1070                                 is_outbound_from_holder: false,
1071                                 counterparty_parameters: Some(CounterpartyChannelTransactionParameters {
1072                                         selected_contest_delay: msg.to_self_delay,
1073                                         pubkeys: counterparty_pubkeys,
1074                                 }),
1075                                 funding_outpoint: None
1076                         },
1077                         funding_transaction: None,
1078
1079                         counterparty_cur_commitment_point: Some(msg.first_per_commitment_point),
1080                         counterparty_prev_commitment_point: None,
1081                         counterparty_node_id,
1082
1083                         counterparty_shutdown_scriptpubkey,
1084
1085                         commitment_secrets: CounterpartyCommitmentSecrets::new(),
1086
1087                         channel_update_status: ChannelUpdateStatus::Enabled,
1088                         closing_signed_in_flight: false,
1089
1090                         announcement_sigs: None,
1091
1092                         #[cfg(any(test, feature = "fuzztarget"))]
1093                         next_local_commitment_tx_fee_info_cached: Mutex::new(None),
1094                         #[cfg(any(test, feature = "fuzztarget"))]
1095                         next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
1096
1097                         workaround_lnd_bug_4006: None,
1098
1099                         #[cfg(any(test, feature = "fuzztarget"))]
1100                         historical_inbound_htlc_fulfills: HashSet::new(),
1101
1102                         channel_type,
1103                 };
1104
1105                 Ok(chan)
1106         }
1107
1108         /// Transaction nomenclature is somewhat confusing here as there are many different cases - a
1109         /// transaction is referred to as "a's transaction" implying that a will be able to broadcast
1110         /// the transaction. Thus, b will generally be sending a signature over such a transaction to
1111         /// a, and a can revoke the transaction by providing b the relevant per_commitment_secret. As
1112         /// such, a transaction is generally the result of b increasing the amount paid to a (or adding
1113         /// an HTLC to a).
1114         /// @local is used only to convert relevant internal structures which refer to remote vs local
1115         /// to decide value of outputs and direction of HTLCs.
1116         /// @generated_by_local is used to determine *which* HTLCs to include - noting that the HTLC
1117         /// state may indicate that one peer has informed the other that they'd like to add an HTLC but
1118         /// have not yet committed it. Such HTLCs will only be included in transactions which are being
1119         /// generated by the peer which proposed adding the HTLCs, and thus we need to understand both
1120         /// which peer generated this transaction and "to whom" this transaction flows.
1121         /// Returns (the transaction info, the number of HTLC outputs which were present in the
1122         /// transaction, the list of HTLCs which were not ignored when building the transaction).
1123         /// Note that below-dust HTLCs are included in the fourth return value, but not the third, and
1124         /// sources are provided only for outbound HTLCs in the fourth return value.
1125         /// Note that fifth and sixth return values are respectively anticipated holder and counterparty
1126         /// balance, not the value actually paid on-chain, which may be zero if it got rounded to dust.
1127         #[inline]
1128         fn build_commitment_transaction<L: Deref>(&self, commitment_number: u64, keys: &TxCreationKeys, local: bool, generated_by_local: bool, logger: &L) -> (CommitmentTransaction, u32, usize, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>, u64, u64) where L::Target: Logger {
1129                 let mut included_dust_htlcs: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::new();
1130                 let num_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len();
1131                 let mut included_non_dust_htlcs: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::with_capacity(num_htlcs);
1132
1133                 let broadcaster_dust_limit_satoshis = if local { self.holder_dust_limit_satoshis } else { self.counterparty_dust_limit_satoshis };
1134                 let mut remote_htlc_total_msat = 0;
1135                 let mut local_htlc_total_msat = 0;
1136                 let mut value_to_self_msat_offset = 0;
1137
1138                 let mut feerate_per_kw = self.feerate_per_kw;
1139                 if let Some((feerate, update_state)) = self.pending_update_fee {
1140                         if match update_state {
1141                                 // Note that these match the inclusion criteria when scanning
1142                                 // pending_inbound_htlcs below.
1143                                 FeeUpdateState::RemoteAnnounced => { debug_assert!(!self.is_outbound()); !generated_by_local },
1144                                 FeeUpdateState::AwaitingRemoteRevokeToAnnounce => { debug_assert!(!self.is_outbound()); !generated_by_local },
1145                                 FeeUpdateState::Outbound => { assert!(self.is_outbound());  generated_by_local },
1146                         } {
1147                                 feerate_per_kw = feerate;
1148                         }
1149                 }
1150
1151                 log_trace!(logger, "Building commitment transaction number {} (really {} xor {}) for channel {} for {}, generated by {} with fee {}...",
1152                         commitment_number, (INITIAL_COMMITMENT_NUMBER - commitment_number),
1153                         get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound()),
1154                         log_bytes!(self.channel_id), if local { "us" } else { "remote" }, if generated_by_local { "us" } else { "remote" }, feerate_per_kw);
1155
1156                 macro_rules! get_htlc_in_commitment {
1157                         ($htlc: expr, $offered: expr) => {
1158                                 HTLCOutputInCommitment {
1159                                         offered: $offered,
1160                                         amount_msat: $htlc.amount_msat,
1161                                         cltv_expiry: $htlc.cltv_expiry,
1162                                         payment_hash: $htlc.payment_hash,
1163                                         transaction_output_index: None
1164                                 }
1165                         }
1166                 }
1167
1168                 macro_rules! add_htlc_output {
1169                         ($htlc: expr, $outbound: expr, $source: expr, $state_name: expr) => {
1170                                 if $outbound == local { // "offered HTLC output"
1171                                         let htlc_in_tx = get_htlc_in_commitment!($htlc, true);
1172                                         if $htlc.amount_msat / 1000 >= broadcaster_dust_limit_satoshis + (feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) {
1173                                                 log_trace!(logger, "   ...including {} {} HTLC {} (hash {}) with value {}", if $outbound { "outbound" } else { "inbound" }, $state_name, $htlc.htlc_id, log_bytes!($htlc.payment_hash.0), $htlc.amount_msat);
1174                                                 included_non_dust_htlcs.push((htlc_in_tx, $source));
1175                                         } else {
1176                                                 log_trace!(logger, "   ...including {} {} dust HTLC {} (hash {}) with value {} due to dust limit", if $outbound { "outbound" } else { "inbound" }, $state_name, $htlc.htlc_id, log_bytes!($htlc.payment_hash.0), $htlc.amount_msat);
1177                                                 included_dust_htlcs.push((htlc_in_tx, $source));
1178                                         }
1179                                 } else {
1180                                         let htlc_in_tx = get_htlc_in_commitment!($htlc, false);
1181                                         if $htlc.amount_msat / 1000 >= broadcaster_dust_limit_satoshis + (feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) {
1182                                                 log_trace!(logger, "   ...including {} {} HTLC {} (hash {}) with value {}", if $outbound { "outbound" } else { "inbound" }, $state_name, $htlc.htlc_id, log_bytes!($htlc.payment_hash.0), $htlc.amount_msat);
1183                                                 included_non_dust_htlcs.push((htlc_in_tx, $source));
1184                                         } else {
1185                                                 log_trace!(logger, "   ...including {} {} dust HTLC {} (hash {}) with value {}", if $outbound { "outbound" } else { "inbound" }, $state_name, $htlc.htlc_id, log_bytes!($htlc.payment_hash.0), $htlc.amount_msat);
1186                                                 included_dust_htlcs.push((htlc_in_tx, $source));
1187                                         }
1188                                 }
1189                         }
1190                 }
1191
1192                 for ref htlc in self.pending_inbound_htlcs.iter() {
1193                         let (include, state_name) = match htlc.state {
1194                                 InboundHTLCState::RemoteAnnounced(_) => (!generated_by_local, "RemoteAnnounced"),
1195                                 InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_) => (!generated_by_local, "AwaitingRemoteRevokeToAnnounce"),
1196                                 InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) => (true, "AwaitingAnnouncedRemoteRevoke"),
1197                                 InboundHTLCState::Committed => (true, "Committed"),
1198                                 InboundHTLCState::LocalRemoved(_) => (!generated_by_local, "LocalRemoved"),
1199                         };
1200
1201                         if include {
1202                                 add_htlc_output!(htlc, false, None, state_name);
1203                                 remote_htlc_total_msat += htlc.amount_msat;
1204                         } else {
1205                                 log_trace!(logger, "   ...not including inbound HTLC {} (hash {}) with value {} due to state ({})", htlc.htlc_id, log_bytes!(htlc.payment_hash.0), htlc.amount_msat, state_name);
1206                                 match &htlc.state {
1207                                         &InboundHTLCState::LocalRemoved(ref reason) => {
1208                                                 if generated_by_local {
1209                                                         if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
1210                                                                 value_to_self_msat_offset += htlc.amount_msat as i64;
1211                                                         }
1212                                                 }
1213                                         },
1214                                         _ => {},
1215                                 }
1216                         }
1217                 }
1218
1219                 for ref htlc in self.pending_outbound_htlcs.iter() {
1220                         let (include, state_name) = match htlc.state {
1221                                 OutboundHTLCState::LocalAnnounced(_) => (generated_by_local, "LocalAnnounced"),
1222                                 OutboundHTLCState::Committed => (true, "Committed"),
1223                                 OutboundHTLCState::RemoteRemoved(_) => (generated_by_local, "RemoteRemoved"),
1224                                 OutboundHTLCState::AwaitingRemoteRevokeToRemove(_) => (generated_by_local, "AwaitingRemoteRevokeToRemove"),
1225                                 OutboundHTLCState::AwaitingRemovedRemoteRevoke(_) => (false, "AwaitingRemovedRemoteRevoke"),
1226                         };
1227
1228                         if include {
1229                                 add_htlc_output!(htlc, true, Some(&htlc.source), state_name);
1230                                 local_htlc_total_msat += htlc.amount_msat;
1231                         } else {
1232                                 log_trace!(logger, "   ...not including outbound HTLC {} (hash {}) with value {} due to state ({})", htlc.htlc_id, log_bytes!(htlc.payment_hash.0), htlc.amount_msat, state_name);
1233                                 match htlc.state {
1234                                         OutboundHTLCState::AwaitingRemoteRevokeToRemove(None)|OutboundHTLCState::AwaitingRemovedRemoteRevoke(None) => {
1235                                                 value_to_self_msat_offset -= htlc.amount_msat as i64;
1236                                         },
1237                                         OutboundHTLCState::RemoteRemoved(None) => {
1238                                                 if !generated_by_local {
1239                                                         value_to_self_msat_offset -= htlc.amount_msat as i64;
1240                                                 }
1241                                         },
1242                                         _ => {},
1243                                 }
1244                         }
1245                 }
1246
1247                 let value_to_self_msat: i64 = (self.value_to_self_msat - local_htlc_total_msat) as i64 + value_to_self_msat_offset;
1248                 assert!(value_to_self_msat >= 0);
1249                 // Note that in case they have several just-awaiting-last-RAA fulfills in-progress (ie
1250                 // AwaitingRemoteRevokeToRemove or AwaitingRemovedRemoteRevoke) we may have allowed them to
1251                 // "violate" their reserve value by couting those against it. Thus, we have to convert
1252                 // everything to i64 before subtracting as otherwise we can overflow.
1253                 let value_to_remote_msat: i64 = (self.channel_value_satoshis * 1000) as i64 - (self.value_to_self_msat as i64) - (remote_htlc_total_msat as i64) - value_to_self_msat_offset;
1254                 assert!(value_to_remote_msat >= 0);
1255
1256                 #[cfg(debug_assertions)]
1257                 {
1258                         // Make sure that the to_self/to_remote is always either past the appropriate
1259                         // channel_reserve *or* it is making progress towards it.
1260                         let mut broadcaster_max_commitment_tx_output = if generated_by_local {
1261                                 self.holder_max_commitment_tx_output.lock().unwrap()
1262                         } else {
1263                                 self.counterparty_max_commitment_tx_output.lock().unwrap()
1264                         };
1265                         debug_assert!(broadcaster_max_commitment_tx_output.0 <= value_to_self_msat as u64 || value_to_self_msat / 1000 >= self.counterparty_selected_channel_reserve_satoshis.unwrap() as i64);
1266                         broadcaster_max_commitment_tx_output.0 = cmp::max(broadcaster_max_commitment_tx_output.0, value_to_self_msat as u64);
1267                         debug_assert!(broadcaster_max_commitment_tx_output.1 <= value_to_remote_msat as u64 || value_to_remote_msat / 1000 >= Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis) as i64);
1268                         broadcaster_max_commitment_tx_output.1 = cmp::max(broadcaster_max_commitment_tx_output.1, value_to_remote_msat as u64);
1269                 }
1270
1271                 let total_fee_sat = Channel::<Signer>::commit_tx_fee_sat(feerate_per_kw, included_non_dust_htlcs.len());
1272                 let (value_to_self, value_to_remote) = if self.is_outbound() {
1273                         (value_to_self_msat / 1000 - total_fee_sat as i64, value_to_remote_msat / 1000)
1274                 } else {
1275                         (value_to_self_msat / 1000, value_to_remote_msat / 1000 - total_fee_sat as i64)
1276                 };
1277
1278                 let mut value_to_a = if local { value_to_self } else { value_to_remote };
1279                 let mut value_to_b = if local { value_to_remote } else { value_to_self };
1280                 let (funding_pubkey_a, funding_pubkey_b) = if local {
1281                         (self.get_holder_pubkeys().funding_pubkey, self.get_counterparty_pubkeys().funding_pubkey)
1282                 } else {
1283                         (self.get_counterparty_pubkeys().funding_pubkey, self.get_holder_pubkeys().funding_pubkey)
1284                 };
1285
1286                 if value_to_a >= (broadcaster_dust_limit_satoshis as i64) {
1287                         log_trace!(logger, "   ...including {} output with value {}", if local { "to_local" } else { "to_remote" }, value_to_a);
1288                 } else {
1289                         value_to_a = 0;
1290                 }
1291
1292                 if value_to_b >= (broadcaster_dust_limit_satoshis as i64) {
1293                         log_trace!(logger, "   ...including {} output with value {}", if local { "to_remote" } else { "to_local" }, value_to_b);
1294                 } else {
1295                         value_to_b = 0;
1296                 }
1297
1298                 let num_nondust_htlcs = included_non_dust_htlcs.len();
1299
1300                 let channel_parameters =
1301                         if local { self.channel_transaction_parameters.as_holder_broadcastable() }
1302                         else { self.channel_transaction_parameters.as_counterparty_broadcastable() };
1303                 let tx = CommitmentTransaction::new_with_auxiliary_htlc_data(commitment_number,
1304                                                                              value_to_a as u64,
1305                                                                              value_to_b as u64,
1306                                                                              false,
1307                                                                              funding_pubkey_a,
1308                                                                              funding_pubkey_b,
1309                                                                              keys.clone(),
1310                                                                              feerate_per_kw,
1311                                                                              &mut included_non_dust_htlcs,
1312                                                                              &channel_parameters
1313                 );
1314                 let mut htlcs_included = included_non_dust_htlcs;
1315                 // The unwrap is safe, because all non-dust HTLCs have been assigned an output index
1316                 htlcs_included.sort_unstable_by_key(|h| h.0.transaction_output_index.unwrap());
1317                 htlcs_included.append(&mut included_dust_htlcs);
1318
1319                 (tx, feerate_per_kw, num_nondust_htlcs, htlcs_included, value_to_self_msat as u64, value_to_remote_msat as u64)
1320         }
1321
1322         #[inline]
1323         fn get_closing_scriptpubkey(&self) -> Script {
1324                 // The shutdown scriptpubkey is set on channel opening when option_upfront_shutdown_script
1325                 // is signaled. Otherwise, it is set when sending a shutdown message. Calling this method
1326                 // outside of those situations will fail.
1327                 self.shutdown_scriptpubkey.clone().unwrap().into_inner()
1328         }
1329
1330         #[inline]
1331         fn get_closing_transaction_weight(&self, a_scriptpubkey: Option<&Script>, b_scriptpubkey: Option<&Script>) -> u64 {
1332                 let mut ret =
1333                 (4 +                                           // version
1334                  1 +                                           // input count
1335                  36 +                                          // prevout
1336                  1 +                                           // script length (0)
1337                  4 +                                           // sequence
1338                  1 +                                           // output count
1339                  4                                             // lock time
1340                  )*4 +                                         // * 4 for non-witness parts
1341                 2 +                                            // witness marker and flag
1342                 1 +                                            // witness element count
1343                 4 +                                            // 4 element lengths (2 sigs, multisig dummy, and witness script)
1344                 self.get_funding_redeemscript().len() as u64 + // funding witness script
1345                 2*(1 + 71);                                    // two signatures + sighash type flags
1346                 if let Some(spk) = a_scriptpubkey {
1347                         ret += ((8+1) +                            // output values and script length
1348                                 spk.len() as u64) * 4;                 // scriptpubkey and witness multiplier
1349                 }
1350                 if let Some(spk) = b_scriptpubkey {
1351                         ret += ((8+1) +                            // output values and script length
1352                                 spk.len() as u64) * 4;                 // scriptpubkey and witness multiplier
1353                 }
1354                 ret
1355         }
1356
1357         #[inline]
1358         fn build_closing_transaction(&self, proposed_total_fee_satoshis: u64, skip_remote_output: bool) -> (ClosingTransaction, u64) {
1359                 assert!(self.pending_inbound_htlcs.is_empty());
1360                 assert!(self.pending_outbound_htlcs.is_empty());
1361                 assert!(self.pending_update_fee.is_none());
1362
1363                 let mut total_fee_satoshis = proposed_total_fee_satoshis;
1364                 let mut value_to_holder: i64 = (self.value_to_self_msat as i64) / 1000 - if self.is_outbound() { total_fee_satoshis as i64 } else { 0 };
1365                 let mut value_to_counterparty: i64 = ((self.channel_value_satoshis * 1000 - self.value_to_self_msat) as i64 / 1000) - if self.is_outbound() { 0 } else { total_fee_satoshis as i64 };
1366
1367                 if value_to_holder < 0 {
1368                         assert!(self.is_outbound());
1369                         total_fee_satoshis += (-value_to_holder) as u64;
1370                 } else if value_to_counterparty < 0 {
1371                         assert!(!self.is_outbound());
1372                         total_fee_satoshis += (-value_to_counterparty) as u64;
1373                 }
1374
1375                 if skip_remote_output || value_to_counterparty as u64 <= self.holder_dust_limit_satoshis {
1376                         value_to_counterparty = 0;
1377                 }
1378
1379                 if value_to_holder as u64 <= self.holder_dust_limit_satoshis {
1380                         value_to_holder = 0;
1381                 }
1382
1383                 assert!(self.shutdown_scriptpubkey.is_some());
1384                 let holder_shutdown_script = self.get_closing_scriptpubkey();
1385                 let counterparty_shutdown_script = self.counterparty_shutdown_scriptpubkey.clone().unwrap();
1386                 let funding_outpoint = self.funding_outpoint().into_bitcoin_outpoint();
1387
1388                 let closing_transaction = ClosingTransaction::new(value_to_holder as u64, value_to_counterparty as u64, holder_shutdown_script, counterparty_shutdown_script, funding_outpoint);
1389                 (closing_transaction, total_fee_satoshis)
1390         }
1391
1392         fn funding_outpoint(&self) -> OutPoint {
1393                 self.channel_transaction_parameters.funding_outpoint.unwrap()
1394         }
1395
1396         #[inline]
1397         /// Creates a set of keys for build_commitment_transaction to generate a transaction which our
1398         /// counterparty will sign (ie DO NOT send signatures over a transaction created by this to
1399         /// our counterparty!)
1400         /// The result is a transaction which we can revoke broadcastership of (ie a "local" transaction)
1401         /// TODO Some magic rust shit to compile-time check this?
1402         fn build_holder_transaction_keys(&self, commitment_number: u64) -> Result<TxCreationKeys, ChannelError> {
1403                 let per_commitment_point = self.holder_signer.get_per_commitment_point(commitment_number, &self.secp_ctx);
1404                 let delayed_payment_base = &self.get_holder_pubkeys().delayed_payment_basepoint;
1405                 let htlc_basepoint = &self.get_holder_pubkeys().htlc_basepoint;
1406                 let counterparty_pubkeys = self.get_counterparty_pubkeys();
1407
1408                 Ok(secp_check!(TxCreationKeys::derive_new(&self.secp_ctx, &per_commitment_point, delayed_payment_base, htlc_basepoint, &counterparty_pubkeys.revocation_basepoint, &counterparty_pubkeys.htlc_basepoint), "Local tx keys generation got bogus keys".to_owned()))
1409         }
1410
1411         #[inline]
1412         /// Creates a set of keys for build_commitment_transaction to generate a transaction which we
1413         /// will sign and send to our counterparty.
1414         /// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
1415         fn build_remote_transaction_keys(&self) -> Result<TxCreationKeys, ChannelError> {
1416                 //TODO: Ensure that the payment_key derived here ends up in the library users' wallet as we
1417                 //may see payments to it!
1418                 let revocation_basepoint = &self.get_holder_pubkeys().revocation_basepoint;
1419                 let htlc_basepoint = &self.get_holder_pubkeys().htlc_basepoint;
1420                 let counterparty_pubkeys = self.get_counterparty_pubkeys();
1421
1422                 Ok(secp_check!(TxCreationKeys::derive_new(&self.secp_ctx, &self.counterparty_cur_commitment_point.unwrap(), &counterparty_pubkeys.delayed_payment_basepoint, &counterparty_pubkeys.htlc_basepoint, revocation_basepoint, htlc_basepoint), "Remote tx keys generation got bogus keys".to_owned()))
1423         }
1424
1425         /// Gets the redeemscript for the funding transaction output (ie the funding transaction output
1426         /// pays to get_funding_redeemscript().to_v0_p2wsh()).
1427         /// Panics if called before accept_channel/new_from_req
1428         pub fn get_funding_redeemscript(&self) -> Script {
1429                 make_funding_redeemscript(&self.get_holder_pubkeys().funding_pubkey, self.counterparty_funding_pubkey())
1430         }
1431
1432         fn get_update_fulfill_htlc<L: Deref>(&mut self, htlc_id_arg: u64, payment_preimage_arg: PaymentPreimage, logger: &L) -> UpdateFulfillFetch where L::Target: Logger {
1433                 // Either ChannelFunded got set (which means it won't be unset) or there is no way any
1434                 // caller thought we could have something claimed (cause we wouldn't have accepted in an
1435                 // incoming HTLC anyway). If we got to ShutdownComplete, callers aren't allowed to call us,
1436                 // either.
1437                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1438                         panic!("Was asked to fulfill an HTLC when channel was not in an operational state");
1439                 }
1440                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
1441
1442                 let payment_hash_calc = PaymentHash(Sha256::hash(&payment_preimage_arg.0[..]).into_inner());
1443
1444                 // ChannelManager may generate duplicate claims/fails due to HTLC update events from
1445                 // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
1446                 // these, but for now we just have to treat them as normal.
1447
1448                 let mut pending_idx = core::usize::MAX;
1449                 let mut htlc_value_msat = 0;
1450                 for (idx, htlc) in self.pending_inbound_htlcs.iter().enumerate() {
1451                         if htlc.htlc_id == htlc_id_arg {
1452                                 assert_eq!(htlc.payment_hash, payment_hash_calc);
1453                                 match htlc.state {
1454                                         InboundHTLCState::Committed => {},
1455                                         InboundHTLCState::LocalRemoved(ref reason) => {
1456                                                 if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
1457                                                 } else {
1458                                                         log_warn!(logger, "Have preimage and want to fulfill HTLC with payment hash {} we already failed against channel {}", log_bytes!(htlc.payment_hash.0), log_bytes!(self.channel_id()));
1459                                                         debug_assert!(false, "Tried to fulfill an HTLC that was already failed");
1460                                                 }
1461                                                 return UpdateFulfillFetch::DuplicateClaim {};
1462                                         },
1463                                         _ => {
1464                                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1465                                                 // Don't return in release mode here so that we can update channel_monitor
1466                                         }
1467                                 }
1468                                 pending_idx = idx;
1469                                 htlc_value_msat = htlc.amount_msat;
1470                                 break;
1471                         }
1472                 }
1473                 if pending_idx == core::usize::MAX {
1474                         #[cfg(any(test, feature = "fuzztarget"))]
1475                         // If we failed to find an HTLC to fulfill, make sure it was previously fulfilled and
1476                         // this is simply a duplicate claim, not previously failed and we lost funds.
1477                         debug_assert!(self.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
1478                         return UpdateFulfillFetch::DuplicateClaim {};
1479                 }
1480
1481                 // Now update local state:
1482                 //
1483                 // We have to put the payment_preimage in the channel_monitor right away here to ensure we
1484                 // can claim it even if the channel hits the chain before we see their next commitment.
1485                 self.latest_monitor_update_id += 1;
1486                 let monitor_update = ChannelMonitorUpdate {
1487                         update_id: self.latest_monitor_update_id,
1488                         updates: vec![ChannelMonitorUpdateStep::PaymentPreimage {
1489                                 payment_preimage: payment_preimage_arg.clone(),
1490                         }],
1491                 };
1492
1493                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
1494                         for pending_update in self.holding_cell_htlc_updates.iter() {
1495                                 match pending_update {
1496                                         &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
1497                                                 if htlc_id_arg == htlc_id {
1498                                                         // Make sure we don't leave latest_monitor_update_id incremented here:
1499                                                         self.latest_monitor_update_id -= 1;
1500                                                         #[cfg(any(test, feature = "fuzztarget"))]
1501                                                         debug_assert!(self.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
1502                                                         return UpdateFulfillFetch::DuplicateClaim {};
1503                                                 }
1504                                         },
1505                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
1506                                                 if htlc_id_arg == htlc_id {
1507                                                         log_warn!(logger, "Have preimage and want to fulfill HTLC with pending failure against channel {}", log_bytes!(self.channel_id()));
1508                                                         // TODO: We may actually be able to switch to a fulfill here, though its
1509                                                         // rare enough it may not be worth the complexity burden.
1510                                                         debug_assert!(false, "Tried to fulfill an HTLC that was already failed");
1511                                                         return UpdateFulfillFetch::NewClaim { monitor_update, htlc_value_msat, msg: None };
1512                                                 }
1513                                         },
1514                                         _ => {}
1515                                 }
1516                         }
1517                         log_trace!(logger, "Adding HTLC claim to holding_cell in channel {}! Current state: {}", log_bytes!(self.channel_id()), self.channel_state);
1518                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::ClaimHTLC {
1519                                 payment_preimage: payment_preimage_arg, htlc_id: htlc_id_arg,
1520                         });
1521                         #[cfg(any(test, feature = "fuzztarget"))]
1522                         self.historical_inbound_htlc_fulfills.insert(htlc_id_arg);
1523                         return UpdateFulfillFetch::NewClaim { monitor_update, htlc_value_msat, msg: None };
1524                 }
1525                 #[cfg(any(test, feature = "fuzztarget"))]
1526                 self.historical_inbound_htlc_fulfills.insert(htlc_id_arg);
1527
1528                 {
1529                         let htlc = &mut self.pending_inbound_htlcs[pending_idx];
1530                         if let InboundHTLCState::Committed = htlc.state {
1531                         } else {
1532                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1533                                 return UpdateFulfillFetch::NewClaim { monitor_update, htlc_value_msat, msg: None };
1534                         }
1535                         log_trace!(logger, "Upgrading HTLC {} to LocalRemoved with a Fulfill in channel {}!", log_bytes!(htlc.payment_hash.0), log_bytes!(self.channel_id));
1536                         htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::Fulfill(payment_preimage_arg.clone()));
1537                 }
1538
1539                 UpdateFulfillFetch::NewClaim {
1540                         monitor_update,
1541                         htlc_value_msat,
1542                         msg: Some(msgs::UpdateFulfillHTLC {
1543                                 channel_id: self.channel_id(),
1544                                 htlc_id: htlc_id_arg,
1545                                 payment_preimage: payment_preimage_arg,
1546                         }),
1547                 }
1548         }
1549
1550         pub fn get_update_fulfill_htlc_and_commit<L: Deref>(&mut self, htlc_id: u64, payment_preimage: PaymentPreimage, logger: &L) -> Result<UpdateFulfillCommitFetch, (ChannelError, ChannelMonitorUpdate)> where L::Target: Logger {
1551                 match self.get_update_fulfill_htlc(htlc_id, payment_preimage, logger) {
1552                         UpdateFulfillFetch::NewClaim { mut monitor_update, htlc_value_msat, msg: Some(update_fulfill_htlc) } => {
1553                                 let (commitment, mut additional_update) = match self.send_commitment_no_status_check(logger) {
1554                                         Err(e) => return Err((e, monitor_update)),
1555                                         Ok(res) => res
1556                                 };
1557                                 // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
1558                                 // strictly increasing by one, so decrement it here.
1559                                 self.latest_monitor_update_id = monitor_update.update_id;
1560                                 monitor_update.updates.append(&mut additional_update.updates);
1561                                 Ok(UpdateFulfillCommitFetch::NewClaim { monitor_update, htlc_value_msat, msgs: Some((update_fulfill_htlc, commitment)) })
1562                         },
1563                         UpdateFulfillFetch::NewClaim { monitor_update, htlc_value_msat, msg: None } =>
1564                                 Ok(UpdateFulfillCommitFetch::NewClaim { monitor_update, htlc_value_msat, msgs: None }),
1565                         UpdateFulfillFetch::DuplicateClaim {} => Ok(UpdateFulfillCommitFetch::DuplicateClaim {}),
1566                 }
1567         }
1568
1569         /// We can only have one resolution per HTLC. In some cases around reconnect, we may fulfill
1570         /// an HTLC more than once or fulfill once and then attempt to fail after reconnect. We cannot,
1571         /// however, fail more than once as we wait for an upstream failure to be irrevocably committed
1572         /// before we fail backwards.
1573         /// If we do fail twice, we debug_assert!(false) and return Ok(None). Thus, will always return
1574         /// Ok(_) if debug assertions are turned on or preconditions are met.
1575         pub fn get_update_fail_htlc<L: Deref>(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket, logger: &L) -> Result<Option<msgs::UpdateFailHTLC>, ChannelError> where L::Target: Logger {
1576                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1577                         panic!("Was asked to fail an HTLC when channel was not in an operational state");
1578                 }
1579                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
1580
1581                 // ChannelManager may generate duplicate claims/fails due to HTLC update events from
1582                 // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
1583                 // these, but for now we just have to treat them as normal.
1584
1585                 let mut pending_idx = core::usize::MAX;
1586                 for (idx, htlc) in self.pending_inbound_htlcs.iter().enumerate() {
1587                         if htlc.htlc_id == htlc_id_arg {
1588                                 match htlc.state {
1589                                         InboundHTLCState::Committed => {},
1590                                         InboundHTLCState::LocalRemoved(ref reason) => {
1591                                                 if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
1592                                                 } else {
1593                                                         debug_assert!(false, "Tried to fail an HTLC that was already failed");
1594                                                 }
1595                                                 return Ok(None);
1596                                         },
1597                                         _ => {
1598                                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1599                                                 return Err(ChannelError::Ignore(format!("Unable to find a pending HTLC which matched the given HTLC ID ({})", htlc.htlc_id)));
1600                                         }
1601                                 }
1602                                 pending_idx = idx;
1603                         }
1604                 }
1605                 if pending_idx == core::usize::MAX {
1606                         #[cfg(any(test, feature = "fuzztarget"))]
1607                         // If we failed to find an HTLC to fail, make sure it was previously fulfilled and this
1608                         // is simply a duplicate fail, not previously failed and we failed-back too early.
1609                         debug_assert!(self.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
1610                         return Ok(None);
1611                 }
1612
1613                 // Now update local state:
1614                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
1615                         for pending_update in self.holding_cell_htlc_updates.iter() {
1616                                 match pending_update {
1617                                         &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
1618                                                 if htlc_id_arg == htlc_id {
1619                                                         #[cfg(any(test, feature = "fuzztarget"))]
1620                                                         debug_assert!(self.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
1621                                                         return Ok(None);
1622                                                 }
1623                                         },
1624                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
1625                                                 if htlc_id_arg == htlc_id {
1626                                                         debug_assert!(false, "Tried to fail an HTLC that was already failed");
1627                                                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
1628                                                 }
1629                                         },
1630                                         _ => {}
1631                                 }
1632                         }
1633                         log_trace!(logger, "Placing failure for HTLC ID {} in holding cell in channel {}.", htlc_id_arg, log_bytes!(self.channel_id()));
1634                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::FailHTLC {
1635                                 htlc_id: htlc_id_arg,
1636                                 err_packet,
1637                         });
1638                         return Ok(None);
1639                 }
1640
1641                 log_trace!(logger, "Failing HTLC ID {} back with a update_fail_htlc message in channel {}.", htlc_id_arg, log_bytes!(self.channel_id()));
1642                 {
1643                         let htlc = &mut self.pending_inbound_htlcs[pending_idx];
1644                         htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(err_packet.clone()));
1645                 }
1646
1647                 Ok(Some(msgs::UpdateFailHTLC {
1648                         channel_id: self.channel_id(),
1649                         htlc_id: htlc_id_arg,
1650                         reason: err_packet
1651                 }))
1652         }
1653
1654         // Message handlers:
1655
1656         pub fn accept_channel(&mut self, msg: &msgs::AcceptChannel, config: &UserConfig, their_features: &InitFeatures) -> Result<(), ChannelError> {
1657                 // Check sanity of message fields:
1658                 if !self.is_outbound() {
1659                         return Err(ChannelError::Close("Got an accept_channel message from an inbound peer".to_owned()));
1660                 }
1661                 if self.channel_state != ChannelState::OurInitSent as u32 {
1662                         return Err(ChannelError::Close("Got an accept_channel message at a strange time".to_owned()));
1663                 }
1664                 if msg.dust_limit_satoshis > 21000000 * 100000000 {
1665                         return Err(ChannelError::Close(format!("Peer never wants payout outputs? dust_limit_satoshis was {}", msg.dust_limit_satoshis)));
1666                 }
1667                 if msg.channel_reserve_satoshis > self.channel_value_satoshis {
1668                         return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must not be greater than ({})", msg.channel_reserve_satoshis, self.channel_value_satoshis)));
1669                 }
1670                 if msg.channel_reserve_satoshis < self.holder_dust_limit_satoshis {
1671                         return Err(ChannelError::Close(format!("Peer never wants payout outputs? channel_reserve_satoshis was ({}). dust_limit is ({})", msg.channel_reserve_satoshis, self.holder_dust_limit_satoshis)));
1672                 }
1673                 let remote_reserve = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis);
1674                 if msg.dust_limit_satoshis > remote_reserve {
1675                         return Err(ChannelError::Close(format!("Dust limit ({}) is bigger than our channel reserve ({})", msg.dust_limit_satoshis, remote_reserve)));
1676                 }
1677                 let full_channel_value_msat = (self.channel_value_satoshis - msg.channel_reserve_satoshis) * 1000;
1678                 if msg.htlc_minimum_msat >= full_channel_value_msat {
1679                         return Err(ChannelError::Close(format!("Minimum htlc value ({}) is full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat)));
1680                 }
1681                 let max_delay_acceptable = u16::min(config.peer_channel_config_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
1682                 if msg.to_self_delay > max_delay_acceptable {
1683                         return Err(ChannelError::Close(format!("They wanted our payments to be delayed by a needlessly long period. Upper limit: {}. Actual: {}", max_delay_acceptable, msg.to_self_delay)));
1684                 }
1685                 if msg.max_accepted_htlcs < 1 {
1686                         return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel".to_owned()));
1687                 }
1688                 if msg.max_accepted_htlcs > MAX_HTLCS {
1689                         return Err(ChannelError::Close(format!("max_accepted_htlcs was {}. It must not be larger than {}", msg.max_accepted_htlcs, MAX_HTLCS)));
1690                 }
1691
1692                 // Now check against optional parameters as set by config...
1693                 if msg.htlc_minimum_msat > config.peer_channel_config_limits.max_htlc_minimum_msat {
1694                         return Err(ChannelError::Close(format!("htlc_minimum_msat ({}) is higher than the user specified limit ({})", msg.htlc_minimum_msat, config.peer_channel_config_limits.max_htlc_minimum_msat)));
1695                 }
1696                 if msg.max_htlc_value_in_flight_msat < config.peer_channel_config_limits.min_max_htlc_value_in_flight_msat {
1697                         return Err(ChannelError::Close(format!("max_htlc_value_in_flight_msat ({}) is less than the user specified limit ({})", msg.max_htlc_value_in_flight_msat, config.peer_channel_config_limits.min_max_htlc_value_in_flight_msat)));
1698                 }
1699                 if msg.channel_reserve_satoshis > config.peer_channel_config_limits.max_channel_reserve_satoshis {
1700                         return Err(ChannelError::Close(format!("channel_reserve_satoshis ({}) is higher than the user specified limit ({})", msg.channel_reserve_satoshis, config.peer_channel_config_limits.max_channel_reserve_satoshis)));
1701                 }
1702                 if msg.max_accepted_htlcs < config.peer_channel_config_limits.min_max_accepted_htlcs {
1703                         return Err(ChannelError::Close(format!("max_accepted_htlcs ({}) is less than the user specified limit ({})", msg.max_accepted_htlcs, config.peer_channel_config_limits.min_max_accepted_htlcs)));
1704                 }
1705                 if msg.dust_limit_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
1706                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the implementation limit ({})", msg.dust_limit_satoshis, MIN_CHAN_DUST_LIMIT_SATOSHIS)));
1707                 }
1708                 if msg.dust_limit_satoshis > MAX_CHAN_DUST_LIMIT_SATOSHIS {
1709                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the implementation limit ({})", msg.dust_limit_satoshis, MAX_CHAN_DUST_LIMIT_SATOSHIS)));
1710                 }
1711                 if msg.minimum_depth > config.peer_channel_config_limits.max_minimum_depth {
1712                         return Err(ChannelError::Close(format!("We consider the minimum depth to be unreasonably large. Expected minimum: ({}). Actual: ({})", config.peer_channel_config_limits.max_minimum_depth, msg.minimum_depth)));
1713                 }
1714                 if msg.minimum_depth == 0 {
1715                         // Note that if this changes we should update the serialization minimum version to
1716                         // indicate to older clients that they don't understand some features of the current
1717                         // channel.
1718                         return Err(ChannelError::Close("Minimum confirmation depth must be at least 1".to_owned()));
1719                 }
1720
1721                 let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() {
1722                         match &msg.shutdown_scriptpubkey {
1723                                 &OptionalField::Present(ref script) => {
1724                                         // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything
1725                                         if script.len() == 0 {
1726                                                 None
1727                                         } else {
1728                                                 if !script::is_bolt2_compliant(&script, their_features) {
1729                                                         return Err(ChannelError::Close(format!("Peer is signaling upfront_shutdown but has provided an unacceptable scriptpubkey format: {}", script)));
1730                                                 }
1731                                                 Some(script.clone())
1732                                         }
1733                                 },
1734                                 // Peer is signaling upfront shutdown but don't opt-out with correct mechanism (a.k.a 0-length script). Peer looks buggy, we fail the channel
1735                                 &OptionalField::Absent => {
1736                                         return Err(ChannelError::Close("Peer is signaling upfront_shutdown but we don't get any script. Use 0-length script to opt-out".to_owned()));
1737                                 }
1738                         }
1739                 } else { None };
1740
1741                 self.counterparty_dust_limit_satoshis = msg.dust_limit_satoshis;
1742                 self.counterparty_max_htlc_value_in_flight_msat = cmp::min(msg.max_htlc_value_in_flight_msat, self.channel_value_satoshis * 1000);
1743                 self.counterparty_selected_channel_reserve_satoshis = Some(msg.channel_reserve_satoshis);
1744                 self.counterparty_htlc_minimum_msat = msg.htlc_minimum_msat;
1745                 self.counterparty_max_accepted_htlcs = msg.max_accepted_htlcs;
1746                 self.minimum_depth = Some(msg.minimum_depth);
1747
1748                 let counterparty_pubkeys = ChannelPublicKeys {
1749                         funding_pubkey: msg.funding_pubkey,
1750                         revocation_basepoint: msg.revocation_basepoint,
1751                         payment_point: msg.payment_point,
1752                         delayed_payment_basepoint: msg.delayed_payment_basepoint,
1753                         htlc_basepoint: msg.htlc_basepoint
1754                 };
1755
1756                 self.channel_transaction_parameters.counterparty_parameters = Some(CounterpartyChannelTransactionParameters {
1757                         selected_contest_delay: msg.to_self_delay,
1758                         pubkeys: counterparty_pubkeys,
1759                 });
1760
1761                 self.counterparty_cur_commitment_point = Some(msg.first_per_commitment_point);
1762                 self.counterparty_shutdown_scriptpubkey = counterparty_shutdown_scriptpubkey;
1763
1764                 self.channel_state = ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32;
1765
1766                 Ok(())
1767         }
1768
1769         fn funding_created_signature<L: Deref>(&mut self, sig: &Signature, logger: &L) -> Result<(Txid, CommitmentTransaction, Signature), ChannelError> where L::Target: Logger {
1770                 let funding_script = self.get_funding_redeemscript();
1771
1772                 let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number)?;
1773                 let initial_commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, false, logger).0;
1774                 {
1775                         let trusted_tx = initial_commitment_tx.trust();
1776                         let initial_commitment_bitcoin_tx = trusted_tx.built_transaction();
1777                         let sighash = initial_commitment_bitcoin_tx.get_sighash_all(&funding_script, self.channel_value_satoshis);
1778                         // They sign the holder commitment transaction...
1779                         log_trace!(logger, "Checking funding_created tx signature {} by key {} against tx {} (sighash {}) with redeemscript {} for channel {}.",
1780                                 log_bytes!(sig.serialize_compact()[..]), log_bytes!(self.counterparty_funding_pubkey().serialize()),
1781                                 encode::serialize_hex(&initial_commitment_bitcoin_tx.transaction), log_bytes!(sighash[..]),
1782                                 encode::serialize_hex(&funding_script), log_bytes!(self.channel_id()));
1783                         secp_check!(self.secp_ctx.verify(&sighash, &sig, self.counterparty_funding_pubkey()), "Invalid funding_created signature from peer".to_owned());
1784                 }
1785
1786                 let counterparty_keys = self.build_remote_transaction_keys()?;
1787                 let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).0;
1788
1789                 let counterparty_trusted_tx = counterparty_initial_commitment_tx.trust();
1790                 let counterparty_initial_bitcoin_tx = counterparty_trusted_tx.built_transaction();
1791                 log_trace!(logger, "Initial counterparty tx for channel {} is: txid {} tx {}",
1792                         log_bytes!(self.channel_id()), counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
1793
1794                 let counterparty_signature = self.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, &self.secp_ctx)
1795                                 .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0;
1796
1797                 // We sign "counterparty" commitment transaction, allowing them to broadcast the tx if they wish.
1798                 Ok((counterparty_initial_bitcoin_tx.txid, initial_commitment_tx, counterparty_signature))
1799         }
1800
1801         fn counterparty_funding_pubkey(&self) -> &PublicKey {
1802                 &self.get_counterparty_pubkeys().funding_pubkey
1803         }
1804
1805         pub fn funding_created<L: Deref>(&mut self, msg: &msgs::FundingCreated, best_block: BestBlock, logger: &L) -> Result<(msgs::FundingSigned, ChannelMonitor<Signer>), ChannelError> where L::Target: Logger {
1806                 if self.is_outbound() {
1807                         return Err(ChannelError::Close("Received funding_created for an outbound channel?".to_owned()));
1808                 }
1809                 if self.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
1810                         // BOLT 2 says that if we disconnect before we send funding_signed we SHOULD NOT
1811                         // remember the channel, so it's safe to just send an error_message here and drop the
1812                         // channel.
1813                         return Err(ChannelError::Close("Received funding_created after we got the channel!".to_owned()));
1814                 }
1815                 if self.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
1816                                 self.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
1817                                 self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
1818                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
1819                 }
1820
1821                 let funding_txo = OutPoint { txid: msg.funding_txid, index: msg.funding_output_index };
1822                 self.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
1823                 // This is an externally observable change before we finish all our checks.  In particular
1824                 // funding_created_signature may fail.
1825                 self.holder_signer.ready_channel(&self.channel_transaction_parameters);
1826
1827                 let (counterparty_initial_commitment_txid, initial_commitment_tx, signature) = match self.funding_created_signature(&msg.signature, logger) {
1828                         Ok(res) => res,
1829                         Err(ChannelError::Close(e)) => {
1830                                 self.channel_transaction_parameters.funding_outpoint = None;
1831                                 return Err(ChannelError::Close(e));
1832                         },
1833                         Err(e) => {
1834                                 // The only error we know how to handle is ChannelError::Close, so we fall over here
1835                                 // to make sure we don't continue with an inconsistent state.
1836                                 panic!("unexpected error type from funding_created_signature {:?}", e);
1837                         }
1838                 };
1839
1840                 let holder_commitment_tx = HolderCommitmentTransaction::new(
1841                         initial_commitment_tx,
1842                         msg.signature,
1843                         Vec::new(),
1844                         &self.get_holder_pubkeys().funding_pubkey,
1845                         self.counterparty_funding_pubkey()
1846                 );
1847
1848                 self.holder_signer.validate_holder_commitment(&holder_commitment_tx)
1849                         .map_err(|_| ChannelError::Close("Failed to validate our commitment".to_owned()))?;
1850
1851                 // Now that we're past error-generating stuff, update our local state:
1852
1853                 let funding_redeemscript = self.get_funding_redeemscript();
1854                 let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
1855                 let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound());
1856                 let shutdown_script = self.shutdown_scriptpubkey.clone().map(|script| script.into_inner());
1857                 let channel_monitor = ChannelMonitor::new(self.secp_ctx.clone(), self.holder_signer.clone(),
1858                                                           shutdown_script, self.get_holder_selected_contest_delay(),
1859                                                           &self.destination_script, (funding_txo, funding_txo_script.clone()),
1860                                                           &self.channel_transaction_parameters,
1861                                                           funding_redeemscript.clone(), self.channel_value_satoshis,
1862                                                           obscure_factor,
1863                                                           holder_commitment_tx, best_block);
1864
1865                 channel_monitor.provide_latest_counterparty_commitment_tx(counterparty_initial_commitment_txid, Vec::new(), self.cur_counterparty_commitment_transaction_number, self.counterparty_cur_commitment_point.unwrap(), logger);
1866
1867                 self.channel_state = ChannelState::FundingSent as u32;
1868                 self.channel_id = funding_txo.to_channel_id();
1869                 self.cur_counterparty_commitment_transaction_number -= 1;
1870                 self.cur_holder_commitment_transaction_number -= 1;
1871
1872                 log_info!(logger, "Generated funding_signed for peer for channel {}", log_bytes!(self.channel_id()));
1873
1874                 Ok((msgs::FundingSigned {
1875                         channel_id: self.channel_id,
1876                         signature
1877                 }, channel_monitor))
1878         }
1879
1880         /// Handles a funding_signed message from the remote end.
1881         /// If this call is successful, broadcast the funding transaction (and not before!)
1882         pub fn funding_signed<L: Deref>(&mut self, msg: &msgs::FundingSigned, best_block: BestBlock, logger: &L) -> Result<(ChannelMonitor<Signer>, Transaction), ChannelError> where L::Target: Logger {
1883                 if !self.is_outbound() {
1884                         return Err(ChannelError::Close("Received funding_signed for an inbound channel?".to_owned()));
1885                 }
1886                 if self.channel_state & !(ChannelState::MonitorUpdateFailed as u32) != ChannelState::FundingCreated as u32 {
1887                         return Err(ChannelError::Close("Received funding_signed in strange state!".to_owned()));
1888                 }
1889                 if self.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
1890                                 self.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
1891                                 self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
1892                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
1893                 }
1894
1895                 let funding_script = self.get_funding_redeemscript();
1896
1897                 let counterparty_keys = self.build_remote_transaction_keys()?;
1898                 let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).0;
1899                 let counterparty_trusted_tx = counterparty_initial_commitment_tx.trust();
1900                 let counterparty_initial_bitcoin_tx = counterparty_trusted_tx.built_transaction();
1901
1902                 log_trace!(logger, "Initial counterparty tx for channel {} is: txid {} tx {}",
1903                         log_bytes!(self.channel_id()), counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
1904
1905                 let holder_signer = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number)?;
1906                 let initial_commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &holder_signer, true, false, logger).0;
1907                 {
1908                         let trusted_tx = initial_commitment_tx.trust();
1909                         let initial_commitment_bitcoin_tx = trusted_tx.built_transaction();
1910                         let sighash = initial_commitment_bitcoin_tx.get_sighash_all(&funding_script, self.channel_value_satoshis);
1911                         // They sign our commitment transaction, allowing us to broadcast the tx if we wish.
1912                         if let Err(_) = self.secp_ctx.verify(&sighash, &msg.signature, &self.get_counterparty_pubkeys().funding_pubkey) {
1913                                 return Err(ChannelError::Close("Invalid funding_signed signature from peer".to_owned()));
1914                         }
1915                 }
1916
1917                 let holder_commitment_tx = HolderCommitmentTransaction::new(
1918                         initial_commitment_tx,
1919                         msg.signature,
1920                         Vec::new(),
1921                         &self.get_holder_pubkeys().funding_pubkey,
1922                         self.counterparty_funding_pubkey()
1923                 );
1924
1925                 self.holder_signer.validate_holder_commitment(&holder_commitment_tx)
1926                         .map_err(|_| ChannelError::Close("Failed to validate our commitment".to_owned()))?;
1927
1928
1929                 let funding_redeemscript = self.get_funding_redeemscript();
1930                 let funding_txo = self.get_funding_txo().unwrap();
1931                 let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
1932                 let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound());
1933                 let shutdown_script = self.shutdown_scriptpubkey.clone().map(|script| script.into_inner());
1934                 let channel_monitor = ChannelMonitor::new(self.secp_ctx.clone(), self.holder_signer.clone(),
1935                                                           shutdown_script, self.get_holder_selected_contest_delay(),
1936                                                           &self.destination_script, (funding_txo, funding_txo_script),
1937                                                           &self.channel_transaction_parameters,
1938                                                           funding_redeemscript.clone(), self.channel_value_satoshis,
1939                                                           obscure_factor,
1940                                                           holder_commitment_tx, best_block);
1941
1942                 channel_monitor.provide_latest_counterparty_commitment_tx(counterparty_initial_bitcoin_tx.txid, Vec::new(), self.cur_counterparty_commitment_transaction_number, self.counterparty_cur_commitment_point.unwrap(), logger);
1943
1944                 assert_eq!(self.channel_state & (ChannelState::MonitorUpdateFailed as u32), 0); // We have no had any monitor(s) yet to fail update!
1945                 self.channel_state = ChannelState::FundingSent as u32;
1946                 self.cur_holder_commitment_transaction_number -= 1;
1947                 self.cur_counterparty_commitment_transaction_number -= 1;
1948
1949                 log_info!(logger, "Received funding_signed from peer for channel {}", log_bytes!(self.channel_id()));
1950
1951                 Ok((channel_monitor, self.funding_transaction.as_ref().cloned().unwrap()))
1952         }
1953
1954         pub fn funding_locked<L: Deref>(&mut self, msg: &msgs::FundingLocked, logger: &L) -> Result<(), ChannelError> where L::Target: Logger {
1955                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
1956                         self.workaround_lnd_bug_4006 = Some(msg.clone());
1957                         return Err(ChannelError::Ignore("Peer sent funding_locked when we needed a channel_reestablish. The peer is likely lnd, see https://github.com/lightningnetwork/lnd/issues/4006".to_owned()));
1958                 }
1959
1960                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
1961
1962                 if non_shutdown_state == ChannelState::FundingSent as u32 {
1963                         self.channel_state |= ChannelState::TheirFundingLocked as u32;
1964                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) {
1965                         self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
1966                         self.update_time_counter += 1;
1967                 } else if (self.channel_state & (ChannelState::ChannelFunded as u32) != 0 &&
1968                                  // Note that funding_signed/funding_created will have decremented both by 1!
1969                                  self.cur_holder_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1 &&
1970                                  self.cur_counterparty_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1) ||
1971                                 // If we reconnected before sending our funding locked they may still resend theirs:
1972                                 (self.channel_state & (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32) ==
1973                                                       (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32)) {
1974                         if self.counterparty_cur_commitment_point != Some(msg.next_per_commitment_point) {
1975                                 return Err(ChannelError::Close("Peer sent a reconnect funding_locked with a different point".to_owned()));
1976                         }
1977                         // They probably disconnected/reconnected and re-sent the funding_locked, which is required
1978                         return Ok(());
1979                 } else {
1980                         return Err(ChannelError::Close("Peer sent a funding_locked at a strange time".to_owned()));
1981                 }
1982
1983                 self.counterparty_prev_commitment_point = self.counterparty_cur_commitment_point;
1984                 self.counterparty_cur_commitment_point = Some(msg.next_per_commitment_point);
1985
1986                 log_info!(logger, "Received funding_locked from peer for channel {}", log_bytes!(self.channel_id()));
1987
1988                 Ok(())
1989         }
1990
1991         /// Returns transaction if there is pending funding transaction that is yet to broadcast
1992         pub fn unbroadcasted_funding(&self) -> Option<Transaction> {
1993                  if self.channel_state & (ChannelState::FundingCreated as u32) != 0 {
1994                          self.funding_transaction.clone()
1995                  } else {
1996                          None
1997                  }
1998         }
1999
2000         /// Returns a HTLCStats about inbound pending htlcs
2001         fn get_inbound_pending_htlc_stats(&self, outbound_feerate_update: Option<u32>) -> HTLCStats {
2002                 let mut stats = HTLCStats {
2003                         pending_htlcs: self.pending_inbound_htlcs.len() as u32,
2004                         pending_htlcs_value_msat: 0,
2005                         on_counterparty_tx_dust_exposure_msat: 0,
2006                         on_holder_tx_dust_exposure_msat: 0,
2007                         holding_cell_msat: 0,
2008                 };
2009
2010                 let counterparty_dust_limit_timeout_sat = (self.get_dust_buffer_feerate(outbound_feerate_update) as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
2011                 let holder_dust_limit_success_sat = (self.get_dust_buffer_feerate(outbound_feerate_update) as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
2012                 for ref htlc in self.pending_inbound_htlcs.iter() {
2013                         stats.pending_htlcs_value_msat += htlc.amount_msat;
2014                         if htlc.amount_msat / 1000 < counterparty_dust_limit_timeout_sat {
2015                                 stats.on_counterparty_tx_dust_exposure_msat += htlc.amount_msat;
2016                         }
2017                         if htlc.amount_msat / 1000 < holder_dust_limit_success_sat {
2018                                 stats.on_holder_tx_dust_exposure_msat += htlc.amount_msat;
2019                         }
2020                 }
2021                 stats
2022         }
2023
2024         /// Returns a HTLCStats about pending outbound htlcs, *including* pending adds in our holding cell.
2025         fn get_outbound_pending_htlc_stats(&self, outbound_feerate_update: Option<u32>) -> HTLCStats {
2026                 let mut stats = HTLCStats {
2027                         pending_htlcs: self.pending_outbound_htlcs.len() as u32,
2028                         pending_htlcs_value_msat: 0,
2029                         on_counterparty_tx_dust_exposure_msat: 0,
2030                         on_holder_tx_dust_exposure_msat: 0,
2031                         holding_cell_msat: 0,
2032                 };
2033
2034                 let counterparty_dust_limit_success_sat = (self.get_dust_buffer_feerate(outbound_feerate_update) as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
2035                 let holder_dust_limit_timeout_sat = (self.get_dust_buffer_feerate(outbound_feerate_update) as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
2036                 for ref htlc in self.pending_outbound_htlcs.iter() {
2037                         stats.pending_htlcs_value_msat += htlc.amount_msat;
2038                         if htlc.amount_msat / 1000 < counterparty_dust_limit_success_sat {
2039                                 stats.on_counterparty_tx_dust_exposure_msat += htlc.amount_msat;
2040                         }
2041                         if htlc.amount_msat / 1000 < holder_dust_limit_timeout_sat {
2042                                 stats.on_holder_tx_dust_exposure_msat += htlc.amount_msat;
2043                         }
2044                 }
2045
2046                 for update in self.holding_cell_htlc_updates.iter() {
2047                         if let &HTLCUpdateAwaitingACK::AddHTLC { ref amount_msat, .. } = update {
2048                                 stats.pending_htlcs += 1;
2049                                 stats.pending_htlcs_value_msat += amount_msat;
2050                                 stats.holding_cell_msat += amount_msat;
2051                                 if *amount_msat / 1000 < counterparty_dust_limit_success_sat {
2052                                         stats.on_counterparty_tx_dust_exposure_msat += amount_msat;
2053                                 }
2054                                 if *amount_msat / 1000 < holder_dust_limit_timeout_sat {
2055                                         stats.on_holder_tx_dust_exposure_msat += amount_msat;
2056                                 }
2057                         }
2058                 }
2059                 stats
2060         }
2061
2062         /// Get the available (ie not including pending HTLCs) inbound and outbound balance in msat.
2063         /// Doesn't bother handling the
2064         /// if-we-removed-it-already-but-haven't-fully-resolved-they-can-still-send-an-inbound-HTLC
2065         /// corner case properly.
2066         pub fn get_inbound_outbound_available_balance_msat(&self) -> (u64, u64) {
2067                 // Note that we have to handle overflow due to the above case.
2068                 (
2069                         cmp::max(self.channel_value_satoshis as i64 * 1000
2070                                 - self.value_to_self_msat as i64
2071                                 - self.get_inbound_pending_htlc_stats(None).pending_htlcs_value_msat as i64
2072                                 - Self::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis) as i64 * 1000,
2073                         0) as u64,
2074                         cmp::max(self.value_to_self_msat as i64
2075                                 - self.get_outbound_pending_htlc_stats(None).pending_htlcs_value_msat as i64
2076                                 - self.counterparty_selected_channel_reserve_satoshis.unwrap_or(0) as i64 * 1000,
2077                         0) as u64
2078                 )
2079         }
2080
2081         pub fn get_holder_counterparty_selected_channel_reserve_satoshis(&self) -> (u64, Option<u64>) {
2082                 (Self::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis),
2083                 self.counterparty_selected_channel_reserve_satoshis)
2084         }
2085
2086         // Get the fee cost in MSATS of a commitment tx with a given number of HTLC outputs.
2087         // Note that num_htlcs should not include dust HTLCs.
2088         fn commit_tx_fee_msat(&self, num_htlcs: usize) -> u64 {
2089                 // Note that we need to divide before multiplying to round properly,
2090                 // since the lowest denomination of bitcoin on-chain is the satoshi.
2091                 (COMMITMENT_TX_BASE_WEIGHT + num_htlcs as u64 * COMMITMENT_TX_WEIGHT_PER_HTLC) * self.feerate_per_kw as u64 / 1000 * 1000
2092         }
2093
2094         // Get the fee cost in SATS of a commitment tx with a given number of HTLC outputs.
2095         // Note that num_htlcs should not include dust HTLCs.
2096         #[inline]
2097         fn commit_tx_fee_sat(feerate_per_kw: u32, num_htlcs: usize) -> u64 {
2098                 feerate_per_kw as u64 * (COMMITMENT_TX_BASE_WEIGHT + num_htlcs as u64 * COMMITMENT_TX_WEIGHT_PER_HTLC) / 1000
2099         }
2100
2101         // Get the commitment tx fee for the local's (i.e. our) next commitment transaction based on the
2102         // number of pending HTLCs that are on track to be in our next commitment tx, plus an additional
2103         // HTLC if `fee_spike_buffer_htlc` is Some, plus a new HTLC given by `new_htlc_amount`. Dust HTLCs
2104         // are excluded.
2105         fn next_local_commit_tx_fee_msat(&self, htlc: HTLCCandidate, fee_spike_buffer_htlc: Option<()>) -> u64 {
2106                 assert!(self.is_outbound());
2107
2108                 let real_dust_limit_success_sat = (self.feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
2109                 let real_dust_limit_timeout_sat = (self.feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
2110
2111                 let mut addl_htlcs = 0;
2112                 if fee_spike_buffer_htlc.is_some() { addl_htlcs += 1; }
2113                 match htlc.origin {
2114                         HTLCInitiator::LocalOffered => {
2115                                 if htlc.amount_msat / 1000 >= real_dust_limit_timeout_sat {
2116                                         addl_htlcs += 1;
2117                                 }
2118                         },
2119                         HTLCInitiator::RemoteOffered => {
2120                                 if htlc.amount_msat / 1000 >= real_dust_limit_success_sat {
2121                                         addl_htlcs += 1;
2122                                 }
2123                         }
2124                 }
2125
2126                 let mut included_htlcs = 0;
2127                 for ref htlc in self.pending_inbound_htlcs.iter() {
2128                         if htlc.amount_msat / 1000 < real_dust_limit_success_sat {
2129                                 continue
2130                         }
2131                         // We include LocalRemoved HTLCs here because we may still need to broadcast a commitment
2132                         // transaction including this HTLC if it times out before they RAA.
2133                         included_htlcs += 1;
2134                 }
2135
2136                 for ref htlc in self.pending_outbound_htlcs.iter() {
2137                         if htlc.amount_msat / 1000 < real_dust_limit_timeout_sat {
2138                                 continue
2139                         }
2140                         match htlc.state {
2141                                 OutboundHTLCState::LocalAnnounced {..} => included_htlcs += 1,
2142                                 OutboundHTLCState::Committed => included_htlcs += 1,
2143                                 OutboundHTLCState::RemoteRemoved {..} => included_htlcs += 1,
2144                                 // We don't include AwaitingRemoteRevokeToRemove HTLCs because our next commitment
2145                                 // transaction won't be generated until they send us their next RAA, which will mean
2146                                 // dropping any HTLCs in this state.
2147                                 _ => {},
2148                         }
2149                 }
2150
2151                 for htlc in self.holding_cell_htlc_updates.iter() {
2152                         match htlc {
2153                                 &HTLCUpdateAwaitingACK::AddHTLC { amount_msat, .. } => {
2154                                         if amount_msat / 1000 < real_dust_limit_timeout_sat {
2155                                                 continue
2156                                         }
2157                                         included_htlcs += 1
2158                                 },
2159                                 _ => {}, // Don't include claims/fails that are awaiting ack, because once we get the
2160                                          // ack we're guaranteed to never include them in commitment txs anymore.
2161                         }
2162                 }
2163
2164                 let num_htlcs = included_htlcs + addl_htlcs;
2165                 let res = self.commit_tx_fee_msat(num_htlcs);
2166                 #[cfg(any(test, feature = "fuzztarget"))]
2167                 {
2168                         let mut fee = res;
2169                         if fee_spike_buffer_htlc.is_some() {
2170                                 fee = self.commit_tx_fee_msat(num_htlcs - 1);
2171                         }
2172                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len()
2173                                 + self.holding_cell_htlc_updates.len();
2174                         let commitment_tx_info = CommitmentTxInfoCached {
2175                                 fee,
2176                                 total_pending_htlcs,
2177                                 next_holder_htlc_id: match htlc.origin {
2178                                         HTLCInitiator::LocalOffered => self.next_holder_htlc_id + 1,
2179                                         HTLCInitiator::RemoteOffered => self.next_holder_htlc_id,
2180                                 },
2181                                 next_counterparty_htlc_id: match htlc.origin {
2182                                         HTLCInitiator::LocalOffered => self.next_counterparty_htlc_id,
2183                                         HTLCInitiator::RemoteOffered => self.next_counterparty_htlc_id + 1,
2184                                 },
2185                                 feerate: self.feerate_per_kw,
2186                         };
2187                         *self.next_local_commitment_tx_fee_info_cached.lock().unwrap() = Some(commitment_tx_info);
2188                 }
2189                 res
2190         }
2191
2192         // Get the commitment tx fee for the remote's next commitment transaction based on the number of
2193         // pending HTLCs that are on track to be in their next commitment tx, plus an additional HTLC if
2194         // `fee_spike_buffer_htlc` is Some, plus a new HTLC given by `new_htlc_amount`. Dust HTLCs are
2195         // excluded.
2196         fn next_remote_commit_tx_fee_msat(&self, htlc: HTLCCandidate, fee_spike_buffer_htlc: Option<()>) -> u64 {
2197                 assert!(!self.is_outbound());
2198
2199                 let real_dust_limit_success_sat = (self.feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
2200                 let real_dust_limit_timeout_sat = (self.feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
2201
2202                 let mut addl_htlcs = 0;
2203                 if fee_spike_buffer_htlc.is_some() { addl_htlcs += 1; }
2204                 match htlc.origin {
2205                         HTLCInitiator::LocalOffered => {
2206                                 if htlc.amount_msat / 1000 >= real_dust_limit_success_sat {
2207                                         addl_htlcs += 1;
2208                                 }
2209                         },
2210                         HTLCInitiator::RemoteOffered => {
2211                                 if htlc.amount_msat / 1000 >= real_dust_limit_timeout_sat {
2212                                         addl_htlcs += 1;
2213                                 }
2214                         }
2215                 }
2216
2217                 // When calculating the set of HTLCs which will be included in their next commitment_signed, all
2218                 // non-dust inbound HTLCs are included (as all states imply it will be included) and only
2219                 // committed outbound HTLCs, see below.
2220                 let mut included_htlcs = 0;
2221                 for ref htlc in self.pending_inbound_htlcs.iter() {
2222                         if htlc.amount_msat / 1000 <= real_dust_limit_timeout_sat {
2223                                 continue
2224                         }
2225                         included_htlcs += 1;
2226                 }
2227
2228                 for ref htlc in self.pending_outbound_htlcs.iter() {
2229                         if htlc.amount_msat / 1000 <= real_dust_limit_success_sat {
2230                                 continue
2231                         }
2232                         // We only include outbound HTLCs if it will not be included in their next commitment_signed,
2233                         // i.e. if they've responded to us with an RAA after announcement.
2234                         match htlc.state {
2235                                 OutboundHTLCState::Committed => included_htlcs += 1,
2236                                 OutboundHTLCState::RemoteRemoved {..} => included_htlcs += 1,
2237                                 OutboundHTLCState::LocalAnnounced { .. } => included_htlcs += 1,
2238                                 _ => {},
2239                         }
2240                 }
2241
2242                 let num_htlcs = included_htlcs + addl_htlcs;
2243                 let res = self.commit_tx_fee_msat(num_htlcs);
2244                 #[cfg(any(test, feature = "fuzztarget"))]
2245                 {
2246                         let mut fee = res;
2247                         if fee_spike_buffer_htlc.is_some() {
2248                                 fee = self.commit_tx_fee_msat(num_htlcs - 1);
2249                         }
2250                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len();
2251                         let commitment_tx_info = CommitmentTxInfoCached {
2252                                 fee,
2253                                 total_pending_htlcs,
2254                                 next_holder_htlc_id: match htlc.origin {
2255                                         HTLCInitiator::LocalOffered => self.next_holder_htlc_id + 1,
2256                                         HTLCInitiator::RemoteOffered => self.next_holder_htlc_id,
2257                                 },
2258                                 next_counterparty_htlc_id: match htlc.origin {
2259                                         HTLCInitiator::LocalOffered => self.next_counterparty_htlc_id,
2260                                         HTLCInitiator::RemoteOffered => self.next_counterparty_htlc_id + 1,
2261                                 },
2262                                 feerate: self.feerate_per_kw,
2263                         };
2264                         *self.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = Some(commitment_tx_info);
2265                 }
2266                 res
2267         }
2268
2269         pub fn update_add_htlc<F, L: Deref>(&mut self, msg: &msgs::UpdateAddHTLC, mut pending_forward_status: PendingHTLCStatus, create_pending_htlc_status: F, logger: &L) -> Result<(), ChannelError>
2270         where F: for<'a> Fn(&'a Self, PendingHTLCStatus, u16) -> PendingHTLCStatus, L::Target: Logger {
2271                 // We can't accept HTLCs sent after we've sent a shutdown.
2272                 let local_sent_shutdown = (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::LocalShutdownSent as u32)) != (ChannelState::ChannelFunded as u32);
2273                 if local_sent_shutdown {
2274                         pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x4000|8);
2275                 }
2276                 // If the remote has sent a shutdown prior to adding this HTLC, then they are in violation of the spec.
2277                 let remote_sent_shutdown = (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::RemoteShutdownSent as u32)) != (ChannelState::ChannelFunded as u32);
2278                 if remote_sent_shutdown {
2279                         return Err(ChannelError::Close("Got add HTLC message when channel was not in an operational state".to_owned()));
2280                 }
2281                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2282                         return Err(ChannelError::Close("Peer sent update_add_htlc when we needed a channel_reestablish".to_owned()));
2283                 }
2284                 if msg.amount_msat > self.channel_value_satoshis * 1000 {
2285                         return Err(ChannelError::Close("Remote side tried to send more than the total value of the channel".to_owned()));
2286                 }
2287                 if msg.amount_msat == 0 {
2288                         return Err(ChannelError::Close("Remote side tried to send a 0-msat HTLC".to_owned()));
2289                 }
2290                 if msg.amount_msat < self.holder_htlc_minimum_msat {
2291                         return Err(ChannelError::Close(format!("Remote side tried to send less than our minimum HTLC value. Lower limit: ({}). Actual: ({})", self.holder_htlc_minimum_msat, msg.amount_msat)));
2292                 }
2293
2294                 let inbound_stats = self.get_inbound_pending_htlc_stats(None);
2295                 let outbound_stats = self.get_outbound_pending_htlc_stats(None);
2296                 if inbound_stats.pending_htlcs + 1 > OUR_MAX_HTLCS as u32 {
2297                         return Err(ChannelError::Close(format!("Remote tried to push more than our max accepted HTLCs ({})", OUR_MAX_HTLCS)));
2298                 }
2299                 let holder_max_htlc_value_in_flight_msat = Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis);
2300                 if inbound_stats.pending_htlcs_value_msat + msg.amount_msat > holder_max_htlc_value_in_flight_msat {
2301                         return Err(ChannelError::Close(format!("Remote HTLC add would put them over our max HTLC value ({})", holder_max_htlc_value_in_flight_msat)));
2302                 }
2303                 // Check holder_selected_channel_reserve_satoshis (we're getting paid, so they have to at least meet
2304                 // the reserve_satoshis we told them to always have as direct payment so that they lose
2305                 // something if we punish them for broadcasting an old state).
2306                 // Note that we don't really care about having a small/no to_remote output in our local
2307                 // commitment transactions, as the purpose of the channel reserve is to ensure we can
2308                 // punish *them* if they misbehave, so we discount any outbound HTLCs which will not be
2309                 // present in the next commitment transaction we send them (at least for fulfilled ones,
2310                 // failed ones won't modify value_to_self).
2311                 // Note that we will send HTLCs which another instance of rust-lightning would think
2312                 // violate the reserve value if we do not do this (as we forget inbound HTLCs from the
2313                 // Channel state once they will not be present in the next received commitment
2314                 // transaction).
2315                 let mut removed_outbound_total_msat = 0;
2316                 for ref htlc in self.pending_outbound_htlcs.iter() {
2317                         if let OutboundHTLCState::AwaitingRemoteRevokeToRemove(None) = htlc.state {
2318                                 removed_outbound_total_msat += htlc.amount_msat;
2319                         } else if let OutboundHTLCState::AwaitingRemovedRemoteRevoke(None) = htlc.state {
2320                                 removed_outbound_total_msat += htlc.amount_msat;
2321                         }
2322                 }
2323
2324                 let exposure_dust_limit_timeout_sats = (self.get_dust_buffer_feerate(None) as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
2325                 if msg.amount_msat / 1000 < exposure_dust_limit_timeout_sats {
2326                         let on_counterparty_tx_dust_htlc_exposure_msat = inbound_stats.on_counterparty_tx_dust_exposure_msat + outbound_stats.on_counterparty_tx_dust_exposure_msat + msg.amount_msat;
2327                         if on_counterparty_tx_dust_htlc_exposure_msat > self.get_max_dust_htlc_exposure_msat() {
2328                                 log_info!(logger, "Cannot accept value that would put our exposure to dust HTLCs at {} over the limit {} on counterparty commitment tx",
2329                                         on_counterparty_tx_dust_htlc_exposure_msat, self.get_max_dust_htlc_exposure_msat());
2330                                 pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|7);
2331                         }
2332                 }
2333
2334                 let exposure_dust_limit_success_sats = (self.get_dust_buffer_feerate(None) as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
2335                 if msg.amount_msat / 1000 < exposure_dust_limit_success_sats {
2336                         let on_holder_tx_dust_htlc_exposure_msat = inbound_stats.on_holder_tx_dust_exposure_msat + outbound_stats.on_holder_tx_dust_exposure_msat + msg.amount_msat;
2337                         if on_holder_tx_dust_htlc_exposure_msat > self.get_max_dust_htlc_exposure_msat() {
2338                                 log_info!(logger, "Cannot accept value that would put our exposure to dust HTLCs at {} over the limit {} on holder commitment tx",
2339                                         on_holder_tx_dust_htlc_exposure_msat, self.get_max_dust_htlc_exposure_msat());
2340                                 pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|7);
2341                         }
2342                 }
2343
2344                 let pending_value_to_self_msat =
2345                         self.value_to_self_msat + inbound_stats.pending_htlcs_value_msat - removed_outbound_total_msat;
2346                 let pending_remote_value_msat =
2347                         self.channel_value_satoshis * 1000 - pending_value_to_self_msat;
2348                 if pending_remote_value_msat < msg.amount_msat {
2349                         return Err(ChannelError::Close("Remote HTLC add would overdraw remaining funds".to_owned()));
2350                 }
2351
2352                 // Check that the remote can afford to pay for this HTLC on-chain at the current
2353                 // feerate_per_kw, while maintaining their channel reserve (as required by the spec).
2354                 let remote_commit_tx_fee_msat = if self.is_outbound() { 0 } else {
2355                         let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
2356                         self.next_remote_commit_tx_fee_msat(htlc_candidate, None) // Don't include the extra fee spike buffer HTLC in calculations
2357                 };
2358                 if pending_remote_value_msat - msg.amount_msat < remote_commit_tx_fee_msat {
2359                         return Err(ChannelError::Close("Remote HTLC add would not leave enough to pay for fees".to_owned()));
2360                 };
2361
2362                 let chan_reserve_msat =
2363                         Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis) * 1000;
2364                 if pending_remote_value_msat - msg.amount_msat - remote_commit_tx_fee_msat < chan_reserve_msat {
2365                         return Err(ChannelError::Close("Remote HTLC add would put them under remote reserve value".to_owned()));
2366                 }
2367
2368                 if !self.is_outbound() {
2369                         // `2 *` and `Some(())` is for the fee spike buffer we keep for the remote. This deviates from
2370                         // the spec because in the spec, the fee spike buffer requirement doesn't exist on the
2371                         // receiver's side, only on the sender's.
2372                         // Note that when we eventually remove support for fee updates and switch to anchor output
2373                         // fees, we will drop the `2 *`, since we no longer be as sensitive to fee spikes. But, keep
2374                         // the extra htlc when calculating the next remote commitment transaction fee as we should
2375                         // still be able to afford adding this HTLC plus one more future HTLC, regardless of being
2376                         // sensitive to fee spikes.
2377                         let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
2378                         let remote_fee_cost_incl_stuck_buffer_msat = 2 * self.next_remote_commit_tx_fee_msat(htlc_candidate, Some(()));
2379                         if pending_remote_value_msat - msg.amount_msat - chan_reserve_msat < remote_fee_cost_incl_stuck_buffer_msat {
2380                                 // Note that if the pending_forward_status is not updated here, then it's because we're already failing
2381                                 // the HTLC, i.e. its status is already set to failing.
2382                                 log_info!(logger, "Attempting to fail HTLC due to fee spike buffer violation in channel {}. Rebalancing is required.", log_bytes!(self.channel_id()));
2383                                 pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|7);
2384                         }
2385                 } else {
2386                         // Check that they won't violate our local required channel reserve by adding this HTLC.
2387                         let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
2388                         let local_commit_tx_fee_msat = self.next_local_commit_tx_fee_msat(htlc_candidate, None);
2389                         if self.value_to_self_msat < self.counterparty_selected_channel_reserve_satoshis.unwrap() * 1000 + local_commit_tx_fee_msat {
2390                                 return Err(ChannelError::Close("Cannot accept HTLC that would put our balance under counterparty-announced channel reserve value".to_owned()));
2391                         }
2392                 }
2393                 if self.next_counterparty_htlc_id != msg.htlc_id {
2394                         return Err(ChannelError::Close(format!("Remote skipped HTLC ID (skipped ID: {})", self.next_counterparty_htlc_id)));
2395                 }
2396                 if msg.cltv_expiry >= 500000000 {
2397                         return Err(ChannelError::Close("Remote provided CLTV expiry in seconds instead of block height".to_owned()));
2398                 }
2399
2400                 if self.channel_state & ChannelState::LocalShutdownSent as u32 != 0 {
2401                         if let PendingHTLCStatus::Forward(_) = pending_forward_status {
2402                                 panic!("ChannelManager shouldn't be trying to add a forwardable HTLC after we've started closing");
2403                         }
2404                 }
2405
2406                 // Now update local state:
2407                 self.next_counterparty_htlc_id += 1;
2408                 self.pending_inbound_htlcs.push(InboundHTLCOutput {
2409                         htlc_id: msg.htlc_id,
2410                         amount_msat: msg.amount_msat,
2411                         payment_hash: msg.payment_hash,
2412                         cltv_expiry: msg.cltv_expiry,
2413                         state: InboundHTLCState::RemoteAnnounced(pending_forward_status),
2414                 });
2415                 Ok(())
2416         }
2417
2418         /// Marks an outbound HTLC which we have received update_fail/fulfill/malformed
2419         #[inline]
2420         fn mark_outbound_htlc_removed(&mut self, htlc_id: u64, check_preimage: Option<PaymentHash>, fail_reason: Option<HTLCFailReason>) -> Result<&OutboundHTLCOutput, ChannelError> {
2421                 for htlc in self.pending_outbound_htlcs.iter_mut() {
2422                         if htlc.htlc_id == htlc_id {
2423                                 match check_preimage {
2424                                         None => {},
2425                                         Some(payment_hash) =>
2426                                                 if payment_hash != htlc.payment_hash {
2427                                                         return Err(ChannelError::Close(format!("Remote tried to fulfill HTLC ({}) with an incorrect preimage", htlc_id)));
2428                                                 }
2429                                 };
2430                                 match htlc.state {
2431                                         OutboundHTLCState::LocalAnnounced(_) =>
2432                                                 return Err(ChannelError::Close(format!("Remote tried to fulfill/fail HTLC ({}) before it had been committed", htlc_id))),
2433                                         OutboundHTLCState::Committed => {
2434                                                 htlc.state = OutboundHTLCState::RemoteRemoved(fail_reason);
2435                                         },
2436                                         OutboundHTLCState::AwaitingRemoteRevokeToRemove(_) | OutboundHTLCState::AwaitingRemovedRemoteRevoke(_) | OutboundHTLCState::RemoteRemoved(_) =>
2437                                                 return Err(ChannelError::Close(format!("Remote tried to fulfill/fail HTLC ({}) that they'd already fulfilled/failed", htlc_id))),
2438                                 }
2439                                 return Ok(htlc);
2440                         }
2441                 }
2442                 Err(ChannelError::Close("Remote tried to fulfill/fail an HTLC we couldn't find".to_owned()))
2443         }
2444
2445         pub fn update_fulfill_htlc(&mut self, msg: &msgs::UpdateFulfillHTLC) -> Result<(HTLCSource, u64), ChannelError> {
2446                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2447                         return Err(ChannelError::Close("Got fulfill HTLC message when channel was not in an operational state".to_owned()));
2448                 }
2449                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2450                         return Err(ChannelError::Close("Peer sent update_fulfill_htlc when we needed a channel_reestablish".to_owned()));
2451                 }
2452
2453                 let payment_hash = PaymentHash(Sha256::hash(&msg.payment_preimage.0[..]).into_inner());
2454                 self.mark_outbound_htlc_removed(msg.htlc_id, Some(payment_hash), None).map(|htlc| (htlc.source.clone(), htlc.amount_msat))
2455         }
2456
2457         pub fn update_fail_htlc(&mut self, msg: &msgs::UpdateFailHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> {
2458                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2459                         return Err(ChannelError::Close("Got fail HTLC message when channel was not in an operational state".to_owned()));
2460                 }
2461                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2462                         return Err(ChannelError::Close("Peer sent update_fail_htlc when we needed a channel_reestablish".to_owned()));
2463                 }
2464
2465                 self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason))?;
2466                 Ok(())
2467         }
2468
2469         pub fn update_fail_malformed_htlc(&mut self, msg: &msgs::UpdateFailMalformedHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> {
2470                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2471                         return Err(ChannelError::Close("Got fail malformed HTLC message when channel was not in an operational state".to_owned()));
2472                 }
2473                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2474                         return Err(ChannelError::Close("Peer sent update_fail_malformed_htlc when we needed a channel_reestablish".to_owned()));
2475                 }
2476
2477                 self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason))?;
2478                 Ok(())
2479         }
2480
2481         pub fn commitment_signed<L: Deref>(&mut self, msg: &msgs::CommitmentSigned, logger: &L) -> Result<(msgs::RevokeAndACK, Option<msgs::CommitmentSigned>, ChannelMonitorUpdate), (Option<ChannelMonitorUpdate>, ChannelError)>
2482                 where L::Target: Logger
2483         {
2484                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2485                         return Err((None, ChannelError::Close("Got commitment signed message when channel was not in an operational state".to_owned())));
2486                 }
2487                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2488                         return Err((None, ChannelError::Close("Peer sent commitment_signed when we needed a channel_reestablish".to_owned())));
2489                 }
2490                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() {
2491                         return Err((None, ChannelError::Close("Peer sent commitment_signed after we'd started exchanging closing_signeds".to_owned())));
2492                 }
2493
2494                 let funding_script = self.get_funding_redeemscript();
2495
2496                 let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number).map_err(|e| (None, e))?;
2497
2498                 let (num_htlcs, mut htlcs_cloned, commitment_tx, commitment_txid, feerate_per_kw, _, counterparty_balance_msat) = {
2499                         let commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, false, logger);
2500                         let commitment_txid = {
2501                                 let trusted_tx = commitment_tx.0.trust();
2502                                 let bitcoin_tx = trusted_tx.built_transaction();
2503                                 let sighash = bitcoin_tx.get_sighash_all(&funding_script, self.channel_value_satoshis);
2504
2505                                 log_trace!(logger, "Checking commitment tx signature {} by key {} against tx {} (sighash {}) with redeemscript {} in channel {}",
2506                                         log_bytes!(msg.signature.serialize_compact()[..]),
2507                                         log_bytes!(self.counterparty_funding_pubkey().serialize()), encode::serialize_hex(&bitcoin_tx.transaction),
2508                                         log_bytes!(sighash[..]), encode::serialize_hex(&funding_script), log_bytes!(self.channel_id()));
2509                                 if let Err(_) = self.secp_ctx.verify(&sighash, &msg.signature, &self.counterparty_funding_pubkey()) {
2510                                         return Err((None, ChannelError::Close("Invalid commitment tx signature from peer".to_owned())));
2511                                 }
2512                                 bitcoin_tx.txid
2513                         };
2514                         let htlcs_cloned: Vec<_> = commitment_tx.3.iter().map(|htlc| (htlc.0.clone(), htlc.1.map(|h| h.clone()))).collect();
2515                         (commitment_tx.2, htlcs_cloned, commitment_tx.0, commitment_txid, commitment_tx.1, commitment_tx.4, commitment_tx.5)
2516                 };
2517
2518                 // If our counterparty updated the channel fee in this commitment transaction, check that
2519                 // they can actually afford the new fee now.
2520                 let update_fee = if let Some((_, update_state)) = self.pending_update_fee {
2521                         update_state == FeeUpdateState::RemoteAnnounced
2522                 } else { false };
2523                 if update_fee { debug_assert!(!self.is_outbound()); }
2524                 let total_fee_sat = Channel::<Signer>::commit_tx_fee_sat(feerate_per_kw, num_htlcs);
2525                 if update_fee {
2526                         let counterparty_reserve_we_require = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis);
2527                         if counterparty_balance_msat < total_fee_sat * 1000 + counterparty_reserve_we_require * 1000 {
2528                                 return Err((None, ChannelError::Close("Funding remote cannot afford proposed new fee".to_owned())));
2529                         }
2530                 }
2531                 #[cfg(any(test, feature = "fuzztarget"))]
2532                 {
2533                         if self.is_outbound() {
2534                                 let projected_commit_tx_info = self.next_local_commitment_tx_fee_info_cached.lock().unwrap().take();
2535                                 *self.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = None;
2536                                 if let Some(info) = projected_commit_tx_info {
2537                                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len()
2538                                                 + self.holding_cell_htlc_updates.len();
2539                                         if info.total_pending_htlcs == total_pending_htlcs
2540                                                 && info.next_holder_htlc_id == self.next_holder_htlc_id
2541                                                 && info.next_counterparty_htlc_id == self.next_counterparty_htlc_id
2542                                                 && info.feerate == self.feerate_per_kw {
2543                                                         assert_eq!(total_fee_sat, info.fee / 1000);
2544                                                 }
2545                                 }
2546                         }
2547                 }
2548
2549                 if msg.htlc_signatures.len() != num_htlcs {
2550                         return Err((None, ChannelError::Close(format!("Got wrong number of HTLC signatures ({}) from remote. It must be {}", msg.htlc_signatures.len(), num_htlcs))));
2551                 }
2552
2553                 // TODO: Sadly, we pass HTLCs twice to ChannelMonitor: once via the HolderCommitmentTransaction and once via the update
2554                 let mut htlcs_and_sigs = Vec::with_capacity(htlcs_cloned.len());
2555                 for (idx, (htlc, source)) in htlcs_cloned.drain(..).enumerate() {
2556                         if let Some(_) = htlc.transaction_output_index {
2557                                 let htlc_tx = chan_utils::build_htlc_transaction(&commitment_txid, feerate_per_kw,
2558                                         self.get_counterparty_selected_contest_delay().unwrap(), &htlc,
2559                                         &keys.broadcaster_delayed_payment_key, &keys.revocation_key);
2560
2561                                 let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys);
2562                                 let htlc_sighash = hash_to_message!(&bip143::SigHashCache::new(&htlc_tx).signature_hash(0, &htlc_redeemscript, htlc.amount_msat / 1000, SigHashType::All)[..]);
2563                                 log_trace!(logger, "Checking HTLC tx signature {} by key {} against tx {} (sighash {}) with redeemscript {} in channel {}.",
2564                                         log_bytes!(msg.htlc_signatures[idx].serialize_compact()[..]), log_bytes!(keys.countersignatory_htlc_key.serialize()),
2565                                         encode::serialize_hex(&htlc_tx), log_bytes!(htlc_sighash[..]), encode::serialize_hex(&htlc_redeemscript), log_bytes!(self.channel_id()));
2566                                 if let Err(_) = self.secp_ctx.verify(&htlc_sighash, &msg.htlc_signatures[idx], &keys.countersignatory_htlc_key) {
2567                                         return Err((None, ChannelError::Close("Invalid HTLC tx signature from peer".to_owned())));
2568                                 }
2569                                 htlcs_and_sigs.push((htlc, Some(msg.htlc_signatures[idx]), source));
2570                         } else {
2571                                 htlcs_and_sigs.push((htlc, None, source));
2572                         }
2573                 }
2574
2575                 let holder_commitment_tx = HolderCommitmentTransaction::new(
2576                         commitment_tx,
2577                         msg.signature,
2578                         msg.htlc_signatures.clone(),
2579                         &self.get_holder_pubkeys().funding_pubkey,
2580                         self.counterparty_funding_pubkey()
2581                 );
2582
2583                 let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number - 1, &self.secp_ctx);
2584                 self.holder_signer.validate_holder_commitment(&holder_commitment_tx)
2585                         .map_err(|_| (None, ChannelError::Close("Failed to validate our commitment".to_owned())))?;
2586                 let per_commitment_secret = self.holder_signer.release_commitment_secret(self.cur_holder_commitment_transaction_number + 1);
2587
2588                 // Update state now that we've passed all the can-fail calls...
2589                 let mut need_commitment = false;
2590                 if let &mut Some((_, ref mut update_state)) = &mut self.pending_update_fee {
2591                         if *update_state == FeeUpdateState::RemoteAnnounced {
2592                                 *update_state = FeeUpdateState::AwaitingRemoteRevokeToAnnounce;
2593                                 need_commitment = true;
2594                         }
2595                 }
2596
2597                 self.latest_monitor_update_id += 1;
2598                 let mut monitor_update = ChannelMonitorUpdate {
2599                         update_id: self.latest_monitor_update_id,
2600                         updates: vec![ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo {
2601                                 commitment_tx: holder_commitment_tx,
2602                                 htlc_outputs: htlcs_and_sigs
2603                         }]
2604                 };
2605
2606                 for htlc in self.pending_inbound_htlcs.iter_mut() {
2607                         let new_forward = if let &InboundHTLCState::RemoteAnnounced(ref forward_info) = &htlc.state {
2608                                 Some(forward_info.clone())
2609                         } else { None };
2610                         if let Some(forward_info) = new_forward {
2611                                 log_trace!(logger, "Updating HTLC {} to AwaitingRemoteRevokeToAnnounce due to commitment_signed in channel {}.",
2612                                         log_bytes!(htlc.payment_hash.0), log_bytes!(self.channel_id));
2613                                 htlc.state = InboundHTLCState::AwaitingRemoteRevokeToAnnounce(forward_info);
2614                                 need_commitment = true;
2615                         }
2616                 }
2617                 for htlc in self.pending_outbound_htlcs.iter_mut() {
2618                         if let Some(fail_reason) = if let &mut OutboundHTLCState::RemoteRemoved(ref mut fail_reason) = &mut htlc.state {
2619                                 Some(fail_reason.take())
2620                         } else { None } {
2621                                 log_trace!(logger, "Updating HTLC {} to AwaitingRemoteRevokeToRemove due to commitment_signed in channel {}.",
2622                                         log_bytes!(htlc.payment_hash.0), log_bytes!(self.channel_id));
2623                                 htlc.state = OutboundHTLCState::AwaitingRemoteRevokeToRemove(fail_reason);
2624                                 need_commitment = true;
2625                         }
2626                 }
2627
2628                 self.cur_holder_commitment_transaction_number -= 1;
2629                 // Note that if we need_commitment & !AwaitingRemoteRevoke we'll call
2630                 // send_commitment_no_status_check() next which will reset this to RAAFirst.
2631                 self.resend_order = RAACommitmentOrder::CommitmentFirst;
2632
2633                 if (self.channel_state & ChannelState::MonitorUpdateFailed as u32) != 0 {
2634                         // In case we initially failed monitor updating without requiring a response, we need
2635                         // to make sure the RAA gets sent first.
2636                         self.monitor_pending_revoke_and_ack = true;
2637                         if need_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 {
2638                                 // If we were going to send a commitment_signed after the RAA, go ahead and do all
2639                                 // the corresponding HTLC status updates so that get_last_commitment_update
2640                                 // includes the right HTLCs.
2641                                 self.monitor_pending_commitment_signed = true;
2642                                 let (_, mut additional_update) = self.send_commitment_no_status_check(logger).map_err(|e| (None, e))?;
2643                                 // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2644                                 // strictly increasing by one, so decrement it here.
2645                                 self.latest_monitor_update_id = monitor_update.update_id;
2646                                 monitor_update.updates.append(&mut additional_update.updates);
2647                         }
2648                         log_debug!(logger, "Received valid commitment_signed from peer in channel {}, updated HTLC state but awaiting a monitor update resolution to reply.",
2649                                 log_bytes!(self.channel_id));
2650                         return Err((Some(monitor_update), ChannelError::Ignore("Previous monitor update failure prevented generation of RAA".to_owned())));
2651                 }
2652
2653                 let commitment_signed = if need_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 {
2654                         // If we're AwaitingRemoteRevoke we can't send a new commitment here, but that's ok -
2655                         // we'll send one right away when we get the revoke_and_ack when we
2656                         // free_holding_cell_htlcs().
2657                         let (msg, mut additional_update) = self.send_commitment_no_status_check(logger).map_err(|e| (None, e))?;
2658                         // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2659                         // strictly increasing by one, so decrement it here.
2660                         self.latest_monitor_update_id = monitor_update.update_id;
2661                         monitor_update.updates.append(&mut additional_update.updates);
2662                         Some(msg)
2663                 } else { None };
2664
2665                 log_debug!(logger, "Received valid commitment_signed from peer in channel {}, updating HTLC state and responding with{} a revoke_and_ack.",
2666                         log_bytes!(self.channel_id()), if commitment_signed.is_some() { " our own commitment_signed and" } else { "" });
2667
2668                 Ok((msgs::RevokeAndACK {
2669                         channel_id: self.channel_id,
2670                         per_commitment_secret,
2671                         next_per_commitment_point,
2672                 }, commitment_signed, monitor_update))
2673         }
2674
2675         /// Public version of the below, checking relevant preconditions first.
2676         /// If we're not in a state where freeing the holding cell makes sense, this is a no-op and
2677         /// returns `(None, Vec::new())`.
2678         pub fn maybe_free_holding_cell_htlcs<L: Deref>(&mut self, logger: &L) -> Result<(Option<(msgs::CommitmentUpdate, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>), ChannelError> where L::Target: Logger {
2679                 if self.channel_state >= ChannelState::ChannelFunded as u32 &&
2680                    (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) == 0 {
2681                         self.free_holding_cell_htlcs(logger)
2682                 } else { Ok((None, Vec::new())) }
2683         }
2684
2685         /// Used to fulfill holding_cell_htlcs when we get a remote ack (or implicitly get it by them
2686         /// fulfilling or failing the last pending HTLC)
2687         fn free_holding_cell_htlcs<L: Deref>(&mut self, logger: &L) -> Result<(Option<(msgs::CommitmentUpdate, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>), ChannelError> where L::Target: Logger {
2688                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, 0);
2689                 if self.holding_cell_htlc_updates.len() != 0 || self.holding_cell_update_fee.is_some() {
2690                         log_trace!(logger, "Freeing holding cell with {} HTLC updates{} in channel {}", self.holding_cell_htlc_updates.len(),
2691                                 if self.holding_cell_update_fee.is_some() { " and a fee update" } else { "" }, log_bytes!(self.channel_id()));
2692
2693                         let mut monitor_update = ChannelMonitorUpdate {
2694                                 update_id: self.latest_monitor_update_id + 1, // We don't increment this yet!
2695                                 updates: Vec::new(),
2696                         };
2697
2698                         let mut htlc_updates = Vec::new();
2699                         mem::swap(&mut htlc_updates, &mut self.holding_cell_htlc_updates);
2700                         let mut update_add_htlcs = Vec::with_capacity(htlc_updates.len());
2701                         let mut update_fulfill_htlcs = Vec::with_capacity(htlc_updates.len());
2702                         let mut update_fail_htlcs = Vec::with_capacity(htlc_updates.len());
2703                         let mut htlcs_to_fail = Vec::new();
2704                         for htlc_update in htlc_updates.drain(..) {
2705                                 // Note that this *can* fail, though it should be due to rather-rare conditions on
2706                                 // fee races with adding too many outputs which push our total payments just over
2707                                 // the limit. In case it's less rare than I anticipate, we may want to revisit
2708                                 // handling this case better and maybe fulfilling some of the HTLCs while attempting
2709                                 // to rebalance channels.
2710                                 match &htlc_update {
2711                                         &HTLCUpdateAwaitingACK::AddHTLC {amount_msat, cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet, ..} => {
2712                                                 match self.send_htlc(amount_msat, *payment_hash, cltv_expiry, source.clone(), onion_routing_packet.clone(), logger) {
2713                                                         Ok(update_add_msg_option) => update_add_htlcs.push(update_add_msg_option.unwrap()),
2714                                                         Err(e) => {
2715                                                                 match e {
2716                                                                         ChannelError::Ignore(ref msg) => {
2717                                                                                 log_info!(logger, "Failed to send HTLC with payment_hash {} due to {} in channel {}",
2718                                                                                         log_bytes!(payment_hash.0), msg, log_bytes!(self.channel_id()));
2719                                                                                 // If we fail to send here, then this HTLC should
2720                                                                                 // be failed backwards. Failing to send here
2721                                                                                 // indicates that this HTLC may keep being put back
2722                                                                                 // into the holding cell without ever being
2723                                                                                 // successfully forwarded/failed/fulfilled, causing
2724                                                                                 // our counterparty to eventually close on us.
2725                                                                                 htlcs_to_fail.push((source.clone(), *payment_hash));
2726                                                                         },
2727                                                                         _ => {
2728                                                                                 panic!("Got a non-IgnoreError action trying to send holding cell HTLC");
2729                                                                         },
2730                                                                 }
2731                                                         }
2732                                                 }
2733                                         },
2734                                         &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, htlc_id, .. } => {
2735                                                 // If an HTLC claim was previously added to the holding cell (via
2736                                                 // `get_update_fulfill_htlc`, then generating the claim message itself must
2737                                                 // not fail - any in between attempts to claim the HTLC will have resulted
2738                                                 // in it hitting the holding cell again and we cannot change the state of a
2739                                                 // holding cell HTLC from fulfill to anything else.
2740                                                 let (update_fulfill_msg_option, mut additional_monitor_update) =
2741                                                         if let UpdateFulfillFetch::NewClaim { msg, monitor_update, .. } = self.get_update_fulfill_htlc(htlc_id, *payment_preimage, logger) {
2742                                                                 (msg, monitor_update)
2743                                                         } else { unreachable!() };
2744                                                 update_fulfill_htlcs.push(update_fulfill_msg_option.unwrap());
2745                                                 monitor_update.updates.append(&mut additional_monitor_update.updates);
2746                                         },
2747                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, ref err_packet } => {
2748                                                 match self.get_update_fail_htlc(htlc_id, err_packet.clone(), logger) {
2749                                                         Ok(update_fail_msg_option) => {
2750                                                                 // If an HTLC failure was previously added to the holding cell (via
2751                                                                 // `get_update_fail_htlc`) then generating the fail message itself
2752                                                                 // must not fail - we should never end up in a state where we
2753                                                                 // double-fail an HTLC or fail-then-claim an HTLC as it indicates
2754                                                                 // we didn't wait for a full revocation before failing.
2755                                                                 update_fail_htlcs.push(update_fail_msg_option.unwrap())
2756                                                         },
2757                                                         Err(e) => {
2758                                                                 if let ChannelError::Ignore(_) = e {}
2759                                                                 else {
2760                                                                         panic!("Got a non-IgnoreError action trying to fail holding cell HTLC");
2761                                                                 }
2762                                                         }
2763                                                 }
2764                                         },
2765                                 }
2766                         }
2767                         if update_add_htlcs.is_empty() && update_fulfill_htlcs.is_empty() && update_fail_htlcs.is_empty() && self.holding_cell_update_fee.is_none() {
2768                                 return Ok((None, htlcs_to_fail));
2769                         }
2770                         let update_fee = if let Some(feerate) = self.holding_cell_update_fee.take() {
2771                                 self.send_update_fee(feerate, logger)
2772                         } else {
2773                                 None
2774                         };
2775
2776                         let (commitment_signed, mut additional_update) = self.send_commitment_no_status_check(logger)?;
2777                         // send_commitment_no_status_check and get_update_fulfill_htlc may bump latest_monitor_id
2778                         // but we want them to be strictly increasing by one, so reset it here.
2779                         self.latest_monitor_update_id = monitor_update.update_id;
2780                         monitor_update.updates.append(&mut additional_update.updates);
2781
2782                         log_debug!(logger, "Freeing holding cell in channel {} resulted in {}{} HTLCs added, {} HTLCs fulfilled, and {} HTLCs failed.",
2783                                 log_bytes!(self.channel_id()), if update_fee.is_some() { "a fee update, " } else { "" },
2784                                 update_add_htlcs.len(), update_fulfill_htlcs.len(), update_fail_htlcs.len());
2785
2786                         Ok((Some((msgs::CommitmentUpdate {
2787                                 update_add_htlcs,
2788                                 update_fulfill_htlcs,
2789                                 update_fail_htlcs,
2790                                 update_fail_malformed_htlcs: Vec::new(),
2791                                 update_fee,
2792                                 commitment_signed,
2793                         }, monitor_update)), htlcs_to_fail))
2794                 } else {
2795                         Ok((None, Vec::new()))
2796                 }
2797         }
2798
2799         /// Handles receiving a remote's revoke_and_ack. Note that we may return a new
2800         /// commitment_signed message here in case we had pending outbound HTLCs to add which were
2801         /// waiting on this revoke_and_ack. The generation of this new commitment_signed may also fail,
2802         /// generating an appropriate error *after* the channel state has been updated based on the
2803         /// revoke_and_ack message.
2804         pub fn revoke_and_ack<L: Deref>(&mut self, msg: &msgs::RevokeAndACK, logger: &L) -> Result<RAAUpdates, ChannelError>
2805                 where L::Target: Logger,
2806         {
2807                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2808                         return Err(ChannelError::Close("Got revoke/ACK message when channel was not in an operational state".to_owned()));
2809                 }
2810                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2811                         return Err(ChannelError::Close("Peer sent revoke_and_ack when we needed a channel_reestablish".to_owned()));
2812                 }
2813                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() {
2814                         return Err(ChannelError::Close("Peer sent revoke_and_ack after we'd started exchanging closing_signeds".to_owned()));
2815                 }
2816
2817                 let secret = secp_check!(SecretKey::from_slice(&msg.per_commitment_secret), "Peer provided an invalid per_commitment_secret".to_owned());
2818
2819                 if let Some(counterparty_prev_commitment_point) = self.counterparty_prev_commitment_point {
2820                         if PublicKey::from_secret_key(&self.secp_ctx, &secret) != counterparty_prev_commitment_point {
2821                                 return Err(ChannelError::Close("Got a revoke commitment secret which didn't correspond to their current pubkey".to_owned()));
2822                         }
2823                 }
2824
2825                 if self.channel_state & ChannelState::AwaitingRemoteRevoke as u32 == 0 {
2826                         // Our counterparty seems to have burned their coins to us (by revoking a state when we
2827                         // haven't given them a new commitment transaction to broadcast). We should probably
2828                         // take advantage of this by updating our channel monitor, sending them an error, and
2829                         // waiting for them to broadcast their latest (now-revoked claim). But, that would be a
2830                         // lot of work, and there's some chance this is all a misunderstanding anyway.
2831                         // We have to do *something*, though, since our signer may get mad at us for otherwise
2832                         // jumping a remote commitment number, so best to just force-close and move on.
2833                         return Err(ChannelError::Close("Received an unexpected revoke_and_ack".to_owned()));
2834                 }
2835
2836                 #[cfg(any(test, feature = "fuzztarget"))]
2837                 {
2838                         *self.next_local_commitment_tx_fee_info_cached.lock().unwrap() = None;
2839                         *self.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = None;
2840                 }
2841
2842                 self.holder_signer.validate_counterparty_revocation(
2843                         self.cur_counterparty_commitment_transaction_number + 1,
2844                         &secret
2845                 ).map_err(|_| ChannelError::Close("Failed to validate revocation from peer".to_owned()))?;
2846
2847                 self.commitment_secrets.provide_secret(self.cur_counterparty_commitment_transaction_number + 1, msg.per_commitment_secret)
2848                         .map_err(|_| ChannelError::Close("Previous secrets did not match new one".to_owned()))?;
2849                 self.latest_monitor_update_id += 1;
2850                 let mut monitor_update = ChannelMonitorUpdate {
2851                         update_id: self.latest_monitor_update_id,
2852                         updates: vec![ChannelMonitorUpdateStep::CommitmentSecret {
2853                                 idx: self.cur_counterparty_commitment_transaction_number + 1,
2854                                 secret: msg.per_commitment_secret,
2855                         }],
2856                 };
2857
2858                 // Update state now that we've passed all the can-fail calls...
2859                 // (note that we may still fail to generate the new commitment_signed message, but that's
2860                 // OK, we step the channel here and *then* if the new generation fails we can fail the
2861                 // channel based on that, but stepping stuff here should be safe either way.
2862                 self.channel_state &= !(ChannelState::AwaitingRemoteRevoke as u32);
2863                 self.counterparty_prev_commitment_point = self.counterparty_cur_commitment_point;
2864                 self.counterparty_cur_commitment_point = Some(msg.next_per_commitment_point);
2865                 self.cur_counterparty_commitment_transaction_number -= 1;
2866
2867                 log_trace!(logger, "Updating HTLCs on receipt of RAA in channel {}...", log_bytes!(self.channel_id()));
2868                 let mut to_forward_infos = Vec::new();
2869                 let mut revoked_htlcs = Vec::new();
2870                 let mut finalized_claimed_htlcs = Vec::new();
2871                 let mut update_fail_htlcs = Vec::new();
2872                 let mut update_fail_malformed_htlcs = Vec::new();
2873                 let mut require_commitment = false;
2874                 let mut value_to_self_msat_diff: i64 = 0;
2875
2876                 {
2877                         // Take references explicitly so that we can hold multiple references to self.
2878                         let pending_inbound_htlcs: &mut Vec<_> = &mut self.pending_inbound_htlcs;
2879                         let pending_outbound_htlcs: &mut Vec<_> = &mut self.pending_outbound_htlcs;
2880
2881                         // We really shouldnt have two passes here, but retain gives a non-mutable ref (Rust bug)
2882                         pending_inbound_htlcs.retain(|htlc| {
2883                                 if let &InboundHTLCState::LocalRemoved(ref reason) = &htlc.state {
2884                                         log_trace!(logger, " ...removing inbound LocalRemoved {}", log_bytes!(htlc.payment_hash.0));
2885                                         if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
2886                                                 value_to_self_msat_diff += htlc.amount_msat as i64;
2887                                         }
2888                                         false
2889                                 } else { true }
2890                         });
2891                         pending_outbound_htlcs.retain(|htlc| {
2892                                 if let &OutboundHTLCState::AwaitingRemovedRemoteRevoke(ref fail_reason) = &htlc.state {
2893                                         log_trace!(logger, " ...removing outbound AwaitingRemovedRemoteRevoke {}", log_bytes!(htlc.payment_hash.0));
2894                                         if let Some(reason) = fail_reason.clone() { // We really want take() here, but, again, non-mut ref :(
2895                                                 revoked_htlcs.push((htlc.source.clone(), htlc.payment_hash, reason));
2896                                         } else {
2897                                                 finalized_claimed_htlcs.push(htlc.source.clone());
2898                                                 // They fulfilled, so we sent them money
2899                                                 value_to_self_msat_diff -= htlc.amount_msat as i64;
2900                                         }
2901                                         false
2902                                 } else { true }
2903                         });
2904                         for htlc in pending_inbound_htlcs.iter_mut() {
2905                                 let swap = if let &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_) = &htlc.state {
2906                                         true
2907                                 } else if let &InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) = &htlc.state {
2908                                         true
2909                                 } else { false };
2910                                 if swap {
2911                                         let mut state = InboundHTLCState::Committed;
2912                                         mem::swap(&mut state, &mut htlc.state);
2913
2914                                         if let InboundHTLCState::AwaitingRemoteRevokeToAnnounce(forward_info) = state {
2915                                                 log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce {} to AwaitingAnnouncedRemoteRevoke", log_bytes!(htlc.payment_hash.0));
2916                                                 htlc.state = InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info);
2917                                                 require_commitment = true;
2918                                         } else if let InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info) = state {
2919                                                 match forward_info {
2920                                                         PendingHTLCStatus::Fail(fail_msg) => {
2921                                                                 log_trace!(logger, " ...promoting inbound AwaitingAnnouncedRemoteRevoke {} to LocalRemoved due to PendingHTLCStatus indicating failure", log_bytes!(htlc.payment_hash.0));
2922                                                                 require_commitment = true;
2923                                                                 match fail_msg {
2924                                                                         HTLCFailureMsg::Relay(msg) => {
2925                                                                                 htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(msg.reason.clone()));
2926                                                                                 update_fail_htlcs.push(msg)
2927                                                                         },
2928                                                                         HTLCFailureMsg::Malformed(msg) => {
2929                                                                                 htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailMalformed((msg.sha256_of_onion, msg.failure_code)));
2930                                                                                 update_fail_malformed_htlcs.push(msg)
2931                                                                         },
2932                                                                 }
2933                                                         },
2934                                                         PendingHTLCStatus::Forward(forward_info) => {
2935                                                                 log_trace!(logger, " ...promoting inbound AwaitingAnnouncedRemoteRevoke {} to Committed", log_bytes!(htlc.payment_hash.0));
2936                                                                 to_forward_infos.push((forward_info, htlc.htlc_id));
2937                                                                 htlc.state = InboundHTLCState::Committed;
2938                                                         }
2939                                                 }
2940                                         }
2941                                 }
2942                         }
2943                         for htlc in pending_outbound_htlcs.iter_mut() {
2944                                 if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
2945                                         log_trace!(logger, " ...promoting outbound LocalAnnounced {} to Committed", log_bytes!(htlc.payment_hash.0));
2946                                         htlc.state = OutboundHTLCState::Committed;
2947                                 }
2948                                 if let Some(fail_reason) = if let &mut OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref mut fail_reason) = &mut htlc.state {
2949                                         Some(fail_reason.take())
2950                                 } else { None } {
2951                                         log_trace!(logger, " ...promoting outbound AwaitingRemoteRevokeToRemove {} to AwaitingRemovedRemoteRevoke", log_bytes!(htlc.payment_hash.0));
2952                                         htlc.state = OutboundHTLCState::AwaitingRemovedRemoteRevoke(fail_reason);
2953                                         require_commitment = true;
2954                                 }
2955                         }
2956                 }
2957                 self.value_to_self_msat = (self.value_to_self_msat as i64 + value_to_self_msat_diff) as u64;
2958
2959                 if let Some((feerate, update_state)) = self.pending_update_fee {
2960                         match update_state {
2961                                 FeeUpdateState::Outbound => {
2962                                         debug_assert!(self.is_outbound());
2963                                         log_trace!(logger, " ...promoting outbound fee update {} to Committed", feerate);
2964                                         self.feerate_per_kw = feerate;
2965                                         self.pending_update_fee = None;
2966                                 },
2967                                 FeeUpdateState::RemoteAnnounced => { debug_assert!(!self.is_outbound()); },
2968                                 FeeUpdateState::AwaitingRemoteRevokeToAnnounce => {
2969                                         debug_assert!(!self.is_outbound());
2970                                         log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce fee update {} to Committed", feerate);
2971                                         require_commitment = true;
2972                                         self.feerate_per_kw = feerate;
2973                                         self.pending_update_fee = None;
2974                                 },
2975                         }
2976                 }
2977
2978                 if (self.channel_state & ChannelState::MonitorUpdateFailed as u32) == ChannelState::MonitorUpdateFailed as u32 {
2979                         // We can't actually generate a new commitment transaction (incl by freeing holding
2980                         // cells) while we can't update the monitor, so we just return what we have.
2981                         if require_commitment {
2982                                 self.monitor_pending_commitment_signed = true;
2983                                 // When the monitor updating is restored we'll call get_last_commitment_update(),
2984                                 // which does not update state, but we're definitely now awaiting a remote revoke
2985                                 // before we can step forward any more, so set it here.
2986                                 let (_, mut additional_update) = self.send_commitment_no_status_check(logger)?;
2987                                 // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2988                                 // strictly increasing by one, so decrement it here.
2989                                 self.latest_monitor_update_id = monitor_update.update_id;
2990                                 monitor_update.updates.append(&mut additional_update.updates);
2991                         }
2992                         self.monitor_pending_forwards.append(&mut to_forward_infos);
2993                         self.monitor_pending_failures.append(&mut revoked_htlcs);
2994                         self.monitor_pending_finalized_fulfills.append(&mut finalized_claimed_htlcs);
2995                         log_debug!(logger, "Received a valid revoke_and_ack for channel {} but awaiting a monitor update resolution to reply.", log_bytes!(self.channel_id()));
2996                         return Ok(RAAUpdates {
2997                                 commitment_update: None, finalized_claimed_htlcs: Vec::new(),
2998                                 accepted_htlcs: Vec::new(), failed_htlcs: Vec::new(),
2999                                 monitor_update,
3000                                 holding_cell_failed_htlcs: Vec::new()
3001                         });
3002                 }
3003
3004                 match self.free_holding_cell_htlcs(logger)? {
3005                         (Some((mut commitment_update, mut additional_update)), htlcs_to_fail) => {
3006                                 commitment_update.update_fail_htlcs.reserve(update_fail_htlcs.len());
3007                                 for fail_msg in update_fail_htlcs.drain(..) {
3008                                         commitment_update.update_fail_htlcs.push(fail_msg);
3009                                 }
3010                                 commitment_update.update_fail_malformed_htlcs.reserve(update_fail_malformed_htlcs.len());
3011                                 for fail_msg in update_fail_malformed_htlcs.drain(..) {
3012                                         commitment_update.update_fail_malformed_htlcs.push(fail_msg);
3013                                 }
3014
3015                                 // free_holding_cell_htlcs may bump latest_monitor_id multiple times but we want them to be
3016                                 // strictly increasing by one, so decrement it here.
3017                                 self.latest_monitor_update_id = monitor_update.update_id;
3018                                 monitor_update.updates.append(&mut additional_update.updates);
3019
3020                                 Ok(RAAUpdates {
3021                                         commitment_update: Some(commitment_update),
3022                                         finalized_claimed_htlcs,
3023                                         accepted_htlcs: to_forward_infos,
3024                                         failed_htlcs: revoked_htlcs,
3025                                         monitor_update,
3026                                         holding_cell_failed_htlcs: htlcs_to_fail
3027                                 })
3028                         },
3029                         (None, htlcs_to_fail) => {
3030                                 if require_commitment {
3031                                         let (commitment_signed, mut additional_update) = self.send_commitment_no_status_check(logger)?;
3032
3033                                         // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
3034                                         // strictly increasing by one, so decrement it here.
3035                                         self.latest_monitor_update_id = monitor_update.update_id;
3036                                         monitor_update.updates.append(&mut additional_update.updates);
3037
3038                                         log_debug!(logger, "Received a valid revoke_and_ack for channel {}. Responding with a commitment update with {} HTLCs failed.",
3039                                                 log_bytes!(self.channel_id()), update_fail_htlcs.len() + update_fail_malformed_htlcs.len());
3040                                         Ok(RAAUpdates {
3041                                                 commitment_update: Some(msgs::CommitmentUpdate {
3042                                                         update_add_htlcs: Vec::new(),
3043                                                         update_fulfill_htlcs: Vec::new(),
3044                                                         update_fail_htlcs,
3045                                                         update_fail_malformed_htlcs,
3046                                                         update_fee: None,
3047                                                         commitment_signed
3048                                                 }),
3049                                                 finalized_claimed_htlcs,
3050                                                 accepted_htlcs: to_forward_infos, failed_htlcs: revoked_htlcs,
3051                                                 monitor_update, holding_cell_failed_htlcs: htlcs_to_fail
3052                                         })
3053                                 } else {
3054                                         log_debug!(logger, "Received a valid revoke_and_ack for channel {} with no reply necessary.", log_bytes!(self.channel_id()));
3055                                         Ok(RAAUpdates {
3056                                                 commitment_update: None,
3057                                                 finalized_claimed_htlcs,
3058                                                 accepted_htlcs: to_forward_infos, failed_htlcs: revoked_htlcs,
3059                                                 monitor_update, holding_cell_failed_htlcs: htlcs_to_fail
3060                                         })
3061                                 }
3062                         }
3063                 }
3064         }
3065
3066         /// Adds a pending update to this channel. See the doc for send_htlc for
3067         /// further details on the optionness of the return value.
3068         /// If our balance is too low to cover the cost of the next commitment transaction at the
3069         /// new feerate, the update is cancelled.
3070         /// You MUST call send_commitment prior to any other calls on this Channel
3071         fn send_update_fee<L: Deref>(&mut self, feerate_per_kw: u32, logger: &L) -> Option<msgs::UpdateFee> where L::Target: Logger {
3072                 if !self.is_outbound() {
3073                         panic!("Cannot send fee from inbound channel");
3074                 }
3075                 if !self.is_usable() {
3076                         panic!("Cannot update fee until channel is fully established and we haven't started shutting down");
3077                 }
3078                 if !self.is_live() {
3079                         panic!("Cannot update fee while peer is disconnected/we're awaiting a monitor update (ChannelManager should have caught this)");
3080                 }
3081
3082                 // Before proposing a feerate update, check that we can actually afford the new fee.
3083                 let inbound_stats = self.get_inbound_pending_htlc_stats(Some(feerate_per_kw));
3084                 let outbound_stats = self.get_outbound_pending_htlc_stats(Some(feerate_per_kw));
3085                 let keys = if let Ok(keys) = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number) { keys } else { return None; };
3086                 let (_, _, num_htlcs, _, holder_balance_msat, _) = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, true, logger);
3087                 let total_fee_sat = Channel::<Signer>::commit_tx_fee_sat(feerate_per_kw, num_htlcs + CONCURRENT_INBOUND_HTLC_FEE_BUFFER as usize);
3088                 let holder_balance_msat = holder_balance_msat - outbound_stats.holding_cell_msat;
3089                 if holder_balance_msat < total_fee_sat * 1000 + self.counterparty_selected_channel_reserve_satoshis.unwrap() * 1000 {
3090                         //TODO: auto-close after a number of failures?
3091                         log_debug!(logger, "Cannot afford to send new feerate at {}", feerate_per_kw);
3092                         return None;
3093                 }
3094
3095                 // Note, we evaluate pending htlc "preemptive" trimmed-to-dust threshold at the proposed `feerate_per_kw`.
3096                 let holder_tx_dust_exposure = inbound_stats.on_holder_tx_dust_exposure_msat + outbound_stats.on_holder_tx_dust_exposure_msat;
3097                 let counterparty_tx_dust_exposure = inbound_stats.on_counterparty_tx_dust_exposure_msat + outbound_stats.on_counterparty_tx_dust_exposure_msat;
3098                 if holder_tx_dust_exposure > self.get_max_dust_htlc_exposure_msat() {
3099                         log_debug!(logger, "Cannot afford to send new feerate at {} without infringing max dust htlc exposure", feerate_per_kw);
3100                         return None;
3101                 }
3102                 if counterparty_tx_dust_exposure > self.get_max_dust_htlc_exposure_msat() {
3103                         log_debug!(logger, "Cannot afford to send new feerate at {} without infringing max dust htlc exposure", feerate_per_kw);
3104                         return None;
3105                 }
3106
3107                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
3108                         self.holding_cell_update_fee = Some(feerate_per_kw);
3109                         return None;
3110                 }
3111
3112                 debug_assert!(self.pending_update_fee.is_none());
3113                 self.pending_update_fee = Some((feerate_per_kw, FeeUpdateState::Outbound));
3114
3115                 Some(msgs::UpdateFee {
3116                         channel_id: self.channel_id,
3117                         feerate_per_kw,
3118                 })
3119         }
3120
3121         pub fn send_update_fee_and_commit<L: Deref>(&mut self, feerate_per_kw: u32, logger: &L) -> Result<Option<(msgs::UpdateFee, msgs::CommitmentSigned, ChannelMonitorUpdate)>, ChannelError> where L::Target: Logger {
3122                 match self.send_update_fee(feerate_per_kw, logger) {
3123                         Some(update_fee) => {
3124                                 let (commitment_signed, monitor_update) = self.send_commitment_no_status_check(logger)?;
3125                                 Ok(Some((update_fee, commitment_signed, monitor_update)))
3126                         },
3127                         None => Ok(None)
3128                 }
3129         }
3130
3131         /// Removes any uncommitted inbound HTLCs and resets the state of uncommitted outbound HTLC
3132         /// updates, to be used on peer disconnection. After this, update_*_htlc messages need to be
3133         /// resent.
3134         /// No further message handling calls may be made until a channel_reestablish dance has
3135         /// completed.
3136         pub fn remove_uncommitted_htlcs_and_mark_paused<L: Deref>(&mut self, logger: &L)  where L::Target: Logger {
3137                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
3138                 if self.channel_state < ChannelState::FundingSent as u32 {
3139                         self.channel_state = ChannelState::ShutdownComplete as u32;
3140                         return;
3141                 }
3142                 // Upon reconnect we have to start the closing_signed dance over, but shutdown messages
3143                 // will be retransmitted.
3144                 self.last_sent_closing_fee = None;
3145                 self.pending_counterparty_closing_signed = None;
3146                 self.closing_fee_limits = None;
3147
3148                 let mut inbound_drop_count = 0;
3149                 self.pending_inbound_htlcs.retain(|htlc| {
3150                         match htlc.state {
3151                                 InboundHTLCState::RemoteAnnounced(_) => {
3152                                         // They sent us an update_add_htlc but we never got the commitment_signed.
3153                                         // We'll tell them what commitment_signed we're expecting next and they'll drop
3154                                         // this HTLC accordingly
3155                                         inbound_drop_count += 1;
3156                                         false
3157                                 },
3158                                 InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_)|InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) => {
3159                                         // We received a commitment_signed updating this HTLC and (at least hopefully)
3160                                         // sent a revoke_and_ack (which we can re-transmit) and have heard nothing
3161                                         // in response to it yet, so don't touch it.
3162                                         true
3163                                 },
3164                                 InboundHTLCState::Committed => true,
3165                                 InboundHTLCState::LocalRemoved(_) => {
3166                                         // We (hopefully) sent a commitment_signed updating this HTLC (which we can
3167                                         // re-transmit if needed) and they may have even sent a revoke_and_ack back
3168                                         // (that we missed). Keep this around for now and if they tell us they missed
3169                                         // the commitment_signed we can re-transmit the update then.
3170                                         true
3171                                 },
3172                         }
3173                 });
3174                 self.next_counterparty_htlc_id -= inbound_drop_count;
3175
3176                 if let Some((_, update_state)) = self.pending_update_fee {
3177                         if update_state == FeeUpdateState::RemoteAnnounced {
3178                                 debug_assert!(!self.is_outbound());
3179                                 self.pending_update_fee = None;
3180                         }
3181                 }
3182
3183                 for htlc in self.pending_outbound_htlcs.iter_mut() {
3184                         if let OutboundHTLCState::RemoteRemoved(_) = htlc.state {
3185                                 // They sent us an update to remove this but haven't yet sent the corresponding
3186                                 // commitment_signed, we need to move it back to Committed and they can re-send
3187                                 // the update upon reconnection.
3188                                 htlc.state = OutboundHTLCState::Committed;
3189                         }
3190                 }
3191
3192                 self.channel_state |= ChannelState::PeerDisconnected as u32;
3193                 log_trace!(logger, "Peer disconnection resulted in {} remote-announced HTLC drops on channel {}", inbound_drop_count, log_bytes!(self.channel_id()));
3194         }
3195
3196         /// Indicates that a ChannelMonitor update failed to be stored by the client and further
3197         /// updates are partially paused.
3198         /// This must be called immediately after the call which generated the ChannelMonitor update
3199         /// which failed. The messages which were generated from that call which generated the
3200         /// monitor update failure must *not* have been sent to the remote end, and must instead
3201         /// have been dropped. They will be regenerated when monitor_updating_restored is called.
3202         pub fn monitor_update_failed(&mut self, resend_raa: bool, resend_commitment: bool,
3203                 mut pending_forwards: Vec<(PendingHTLCInfo, u64)>,
3204                 mut pending_fails: Vec<(HTLCSource, PaymentHash, HTLCFailReason)>,
3205                 mut pending_finalized_claimed_htlcs: Vec<HTLCSource>
3206         ) {
3207                 self.monitor_pending_revoke_and_ack |= resend_raa;
3208                 self.monitor_pending_commitment_signed |= resend_commitment;
3209                 self.monitor_pending_forwards.append(&mut pending_forwards);
3210                 self.monitor_pending_failures.append(&mut pending_fails);
3211                 self.monitor_pending_finalized_fulfills.append(&mut pending_finalized_claimed_htlcs);
3212                 self.channel_state |= ChannelState::MonitorUpdateFailed as u32;
3213         }
3214
3215         /// Indicates that the latest ChannelMonitor update has been committed by the client
3216         /// successfully and we should restore normal operation. Returns messages which should be sent
3217         /// to the remote side.
3218         pub fn monitor_updating_restored<L: Deref>(&mut self, logger: &L) -> MonitorRestoreUpdates where L::Target: Logger {
3219                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, ChannelState::MonitorUpdateFailed as u32);
3220                 self.channel_state &= !(ChannelState::MonitorUpdateFailed as u32);
3221
3222                 let funding_broadcastable = if self.channel_state & (ChannelState::FundingSent as u32) != 0 && self.is_outbound() {
3223                         self.funding_transaction.take()
3224                 } else { None };
3225
3226                 // We will never broadcast the funding transaction when we're in MonitorUpdateFailed (and
3227                 // we assume the user never directly broadcasts the funding transaction and waits for us to
3228                 // do it). Thus, we can only ever hit monitor_pending_funding_locked when we're an inbound
3229                 // channel which failed to persist the monitor on funding_created, and we got the funding
3230                 // transaction confirmed before the monitor was persisted.
3231                 let funding_locked = if self.monitor_pending_funding_locked {
3232                         assert!(!self.is_outbound(), "Funding transaction broadcast by the local client before it should have - LDK didn't do it!");
3233                         self.monitor_pending_funding_locked = false;
3234                         let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3235                         Some(msgs::FundingLocked {
3236                                 channel_id: self.channel_id(),
3237                                 next_per_commitment_point,
3238                         })
3239                 } else { None };
3240
3241                 let mut accepted_htlcs = Vec::new();
3242                 mem::swap(&mut accepted_htlcs, &mut self.monitor_pending_forwards);
3243                 let mut failed_htlcs = Vec::new();
3244                 mem::swap(&mut failed_htlcs, &mut self.monitor_pending_failures);
3245                 let mut finalized_claimed_htlcs = Vec::new();
3246                 mem::swap(&mut finalized_claimed_htlcs, &mut self.monitor_pending_finalized_fulfills);
3247
3248                 if self.channel_state & (ChannelState::PeerDisconnected as u32) != 0 {
3249                         self.monitor_pending_revoke_and_ack = false;
3250                         self.monitor_pending_commitment_signed = false;
3251                         return MonitorRestoreUpdates {
3252                                 raa: None, commitment_update: None, order: RAACommitmentOrder::RevokeAndACKFirst,
3253                                 accepted_htlcs, failed_htlcs, finalized_claimed_htlcs, funding_broadcastable, funding_locked
3254                         };
3255                 }
3256
3257                 let raa = if self.monitor_pending_revoke_and_ack {
3258                         Some(self.get_last_revoke_and_ack())
3259                 } else { None };
3260                 let commitment_update = if self.monitor_pending_commitment_signed {
3261                         Some(self.get_last_commitment_update(logger))
3262                 } else { None };
3263
3264                 self.monitor_pending_revoke_and_ack = false;
3265                 self.monitor_pending_commitment_signed = false;
3266                 let order = self.resend_order.clone();
3267                 log_debug!(logger, "Restored monitor updating in channel {} resulting in {}{} commitment update and {} RAA, with {} first",
3268                         log_bytes!(self.channel_id()), if funding_broadcastable.is_some() { "a funding broadcastable, " } else { "" },
3269                         if commitment_update.is_some() { "a" } else { "no" }, if raa.is_some() { "an" } else { "no" },
3270                         match order { RAACommitmentOrder::CommitmentFirst => "commitment", RAACommitmentOrder::RevokeAndACKFirst => "RAA"});
3271                 MonitorRestoreUpdates {
3272                         raa, commitment_update, order, accepted_htlcs, failed_htlcs, finalized_claimed_htlcs, funding_broadcastable, funding_locked
3273                 }
3274         }
3275
3276         pub fn update_fee<F: Deref>(&mut self, fee_estimator: &F, msg: &msgs::UpdateFee) -> Result<(), ChannelError>
3277                 where F::Target: FeeEstimator
3278         {
3279                 if self.is_outbound() {
3280                         return Err(ChannelError::Close("Non-funding remote tried to update channel fee".to_owned()));
3281                 }
3282                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
3283                         return Err(ChannelError::Close("Peer sent update_fee when we needed a channel_reestablish".to_owned()));
3284                 }
3285                 Channel::<Signer>::check_remote_fee(fee_estimator, msg.feerate_per_kw)?;
3286                 let feerate_over_dust_buffer = msg.feerate_per_kw > self.get_dust_buffer_feerate(None);
3287
3288                 self.pending_update_fee = Some((msg.feerate_per_kw, FeeUpdateState::RemoteAnnounced));
3289                 self.update_time_counter += 1;
3290                 // If the feerate has increased over the previous dust buffer (note that
3291                 // `get_dust_buffer_feerate` considers the `pending_update_fee` status), check that we
3292                 // won't be pushed over our dust exposure limit by the feerate increase.
3293                 if feerate_over_dust_buffer {
3294                         let inbound_stats = self.get_inbound_pending_htlc_stats(None);
3295                         let outbound_stats = self.get_outbound_pending_htlc_stats(None);
3296                         let holder_tx_dust_exposure = inbound_stats.on_holder_tx_dust_exposure_msat + outbound_stats.on_holder_tx_dust_exposure_msat;
3297                         let counterparty_tx_dust_exposure = inbound_stats.on_counterparty_tx_dust_exposure_msat + outbound_stats.on_counterparty_tx_dust_exposure_msat;
3298                         if holder_tx_dust_exposure > self.get_max_dust_htlc_exposure_msat() {
3299                                 return Err(ChannelError::Close(format!("Peer sent update_fee with a feerate ({}) which may over-expose us to dust-in-flight on our own transactions (totaling {} msat)",
3300                                         msg.feerate_per_kw, holder_tx_dust_exposure)));
3301                         }
3302                         if counterparty_tx_dust_exposure > self.get_max_dust_htlc_exposure_msat() {
3303                                 return Err(ChannelError::Close(format!("Peer sent update_fee with a feerate ({}) which may over-expose us to dust-in-flight on our counterparty's transactions (totaling {} msat)",
3304                                         msg.feerate_per_kw, counterparty_tx_dust_exposure)));
3305                         }
3306                 }
3307                 Ok(())
3308         }
3309
3310         fn get_last_revoke_and_ack(&self) -> msgs::RevokeAndACK {
3311                 let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3312                 let per_commitment_secret = self.holder_signer.release_commitment_secret(self.cur_holder_commitment_transaction_number + 2);
3313                 msgs::RevokeAndACK {
3314                         channel_id: self.channel_id,
3315                         per_commitment_secret,
3316                         next_per_commitment_point,
3317                 }
3318         }
3319
3320         fn get_last_commitment_update<L: Deref>(&self, logger: &L) -> msgs::CommitmentUpdate where L::Target: Logger {
3321                 let mut update_add_htlcs = Vec::new();
3322                 let mut update_fulfill_htlcs = Vec::new();
3323                 let mut update_fail_htlcs = Vec::new();
3324                 let mut update_fail_malformed_htlcs = Vec::new();
3325
3326                 for htlc in self.pending_outbound_htlcs.iter() {
3327                         if let &OutboundHTLCState::LocalAnnounced(ref onion_packet) = &htlc.state {
3328                                 update_add_htlcs.push(msgs::UpdateAddHTLC {
3329                                         channel_id: self.channel_id(),
3330                                         htlc_id: htlc.htlc_id,
3331                                         amount_msat: htlc.amount_msat,
3332                                         payment_hash: htlc.payment_hash,
3333                                         cltv_expiry: htlc.cltv_expiry,
3334                                         onion_routing_packet: (**onion_packet).clone(),
3335                                 });
3336                         }
3337                 }
3338
3339                 for htlc in self.pending_inbound_htlcs.iter() {
3340                         if let &InboundHTLCState::LocalRemoved(ref reason) = &htlc.state {
3341                                 match reason {
3342                                         &InboundHTLCRemovalReason::FailRelay(ref err_packet) => {
3343                                                 update_fail_htlcs.push(msgs::UpdateFailHTLC {
3344                                                         channel_id: self.channel_id(),
3345                                                         htlc_id: htlc.htlc_id,
3346                                                         reason: err_packet.clone()
3347                                                 });
3348                                         },
3349                                         &InboundHTLCRemovalReason::FailMalformed((ref sha256_of_onion, ref failure_code)) => {
3350                                                 update_fail_malformed_htlcs.push(msgs::UpdateFailMalformedHTLC {
3351                                                         channel_id: self.channel_id(),
3352                                                         htlc_id: htlc.htlc_id,
3353                                                         sha256_of_onion: sha256_of_onion.clone(),
3354                                                         failure_code: failure_code.clone(),
3355                                                 });
3356                                         },
3357                                         &InboundHTLCRemovalReason::Fulfill(ref payment_preimage) => {
3358                                                 update_fulfill_htlcs.push(msgs::UpdateFulfillHTLC {
3359                                                         channel_id: self.channel_id(),
3360                                                         htlc_id: htlc.htlc_id,
3361                                                         payment_preimage: payment_preimage.clone(),
3362                                                 });
3363                                         },
3364                                 }
3365                         }
3366                 }
3367
3368                 let update_fee = if self.is_outbound() && self.pending_update_fee.is_some() {
3369                         Some(msgs::UpdateFee {
3370                                 channel_id: self.channel_id(),
3371                                 feerate_per_kw: self.pending_update_fee.unwrap().0,
3372                         })
3373                 } else { None };
3374
3375                 log_trace!(logger, "Regenerated latest commitment update in channel {} with{} {} update_adds, {} update_fulfills, {} update_fails, and {} update_fail_malformeds",
3376                                 log_bytes!(self.channel_id()), if update_fee.is_some() { " update_fee," } else { "" },
3377                                 update_add_htlcs.len(), update_fulfill_htlcs.len(), update_fail_htlcs.len(), update_fail_malformed_htlcs.len());
3378                 msgs::CommitmentUpdate {
3379                         update_add_htlcs, update_fulfill_htlcs, update_fail_htlcs, update_fail_malformed_htlcs, update_fee,
3380                         commitment_signed: self.send_commitment_no_state_update(logger).expect("It looks like we failed to re-generate a commitment_signed we had previously sent?").0,
3381                 }
3382         }
3383
3384         /// May panic if some calls other than message-handling calls (which will all Err immediately)
3385         /// have been called between remove_uncommitted_htlcs_and_mark_paused and this call.
3386         pub fn channel_reestablish<L: Deref>(&mut self, msg: &msgs::ChannelReestablish, logger: &L) -> Result<(Option<msgs::FundingLocked>, Option<msgs::RevokeAndACK>, Option<msgs::CommitmentUpdate>, Option<ChannelMonitorUpdate>, RAACommitmentOrder, Vec<(HTLCSource, PaymentHash)>, Option<msgs::Shutdown>), ChannelError> where L::Target: Logger {
3387                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == 0 {
3388                         // While BOLT 2 doesn't indicate explicitly we should error this channel here, it
3389                         // almost certainly indicates we are going to end up out-of-sync in some way, so we
3390                         // just close here instead of trying to recover.
3391                         return Err(ChannelError::Close("Peer sent a loose channel_reestablish not after reconnect".to_owned()));
3392                 }
3393
3394                 if msg.next_local_commitment_number >= INITIAL_COMMITMENT_NUMBER || msg.next_remote_commitment_number >= INITIAL_COMMITMENT_NUMBER ||
3395                         msg.next_local_commitment_number == 0 {
3396                         return Err(ChannelError::Close("Peer sent a garbage channel_reestablish".to_owned()));
3397                 }
3398
3399                 if msg.next_remote_commitment_number > 0 {
3400                         match msg.data_loss_protect {
3401                                 OptionalField::Present(ref data_loss) => {
3402                                         let expected_point = self.holder_signer.get_per_commitment_point(INITIAL_COMMITMENT_NUMBER - msg.next_remote_commitment_number + 1, &self.secp_ctx);
3403                                         let given_secret = SecretKey::from_slice(&data_loss.your_last_per_commitment_secret)
3404                                                 .map_err(|_| ChannelError::Close("Peer sent a garbage channel_reestablish with unparseable secret key".to_owned()))?;
3405                                         if expected_point != PublicKey::from_secret_key(&self.secp_ctx, &given_secret) {
3406                                                 return Err(ChannelError::Close("Peer sent a garbage channel_reestablish with secret key not matching the commitment height provided".to_owned()));
3407                                         }
3408                                         if msg.next_remote_commitment_number > INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number {
3409                                                 return Err(ChannelError::CloseDelayBroadcast(
3410                                                         "We have fallen behind - we have received proof that if we broadcast remote is going to claim our funds - we can't do any automated broadcasting".to_owned()
3411                                                 ));
3412                                         }
3413                                 },
3414                                 OptionalField::Absent => {}
3415                         }
3416                 }
3417
3418                 // Go ahead and unmark PeerDisconnected as various calls we may make check for it (and all
3419                 // remaining cases either succeed or ErrorMessage-fail).
3420                 self.channel_state &= !(ChannelState::PeerDisconnected as u32);
3421
3422                 let shutdown_msg = if self.channel_state & (ChannelState::LocalShutdownSent as u32) != 0 {
3423                         assert!(self.shutdown_scriptpubkey.is_some());
3424                         Some(msgs::Shutdown {
3425                                 channel_id: self.channel_id,
3426                                 scriptpubkey: self.get_closing_scriptpubkey(),
3427                         })
3428                 } else { None };
3429
3430                 if self.channel_state & (ChannelState::FundingSent as u32) == ChannelState::FundingSent as u32 {
3431                         // If we're waiting on a monitor update, we shouldn't re-send any funding_locked's.
3432                         if self.channel_state & (ChannelState::OurFundingLocked as u32) == 0 ||
3433                                         self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
3434                                 if msg.next_remote_commitment_number != 0 {
3435                                         return Err(ChannelError::Close("Peer claimed they saw a revoke_and_ack but we haven't sent funding_locked yet".to_owned()));
3436                                 }
3437                                 // Short circuit the whole handler as there is nothing we can resend them
3438                                 return Ok((None, None, None, None, RAACommitmentOrder::CommitmentFirst, Vec::new(), shutdown_msg));
3439                         }
3440
3441                         // We have OurFundingLocked set!
3442                         let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3443                         return Ok((Some(msgs::FundingLocked {
3444                                 channel_id: self.channel_id(),
3445                                 next_per_commitment_point,
3446                         }), None, None, None, RAACommitmentOrder::CommitmentFirst, Vec::new(), shutdown_msg));
3447                 }
3448
3449                 let required_revoke = if msg.next_remote_commitment_number + 1 == INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number {
3450                         // Remote isn't waiting on any RevokeAndACK from us!
3451                         // Note that if we need to repeat our FundingLocked we'll do that in the next if block.
3452                         None
3453                 } else if msg.next_remote_commitment_number + 1 == (INITIAL_COMMITMENT_NUMBER - 1) - self.cur_holder_commitment_transaction_number {
3454                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
3455                                 self.monitor_pending_revoke_and_ack = true;
3456                                 None
3457                         } else {
3458                                 Some(self.get_last_revoke_and_ack())
3459                         }
3460                 } else {
3461                         return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old local commitment transaction".to_owned()));
3462                 };
3463
3464                 // We increment cur_counterparty_commitment_transaction_number only upon receipt of
3465                 // revoke_and_ack, not on sending commitment_signed, so we add one if have
3466                 // AwaitingRemoteRevoke set, which indicates we sent a commitment_signed but haven't gotten
3467                 // the corresponding revoke_and_ack back yet.
3468                 let next_counterparty_commitment_number = INITIAL_COMMITMENT_NUMBER - self.cur_counterparty_commitment_transaction_number + if (self.channel_state & ChannelState::AwaitingRemoteRevoke as u32) != 0 { 1 } else { 0 };
3469
3470                 let resend_funding_locked = if msg.next_local_commitment_number == 1 && INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number == 1 {
3471                         // We should never have to worry about MonitorUpdateFailed resending FundingLocked
3472                         let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3473                         Some(msgs::FundingLocked {
3474                                 channel_id: self.channel_id(),
3475                                 next_per_commitment_point,
3476                         })
3477                 } else { None };
3478
3479                 if msg.next_local_commitment_number == next_counterparty_commitment_number {
3480                         if required_revoke.is_some() {
3481                                 log_debug!(logger, "Reconnected channel {} with only lost outbound RAA", log_bytes!(self.channel_id()));
3482                         } else {
3483                                 log_debug!(logger, "Reconnected channel {} with no loss", log_bytes!(self.channel_id()));
3484                         }
3485
3486                         if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateFailed as u32)) == 0 {
3487                                 // We're up-to-date and not waiting on a remote revoke (if we are our
3488                                 // channel_reestablish should result in them sending a revoke_and_ack), but we may
3489                                 // have received some updates while we were disconnected. Free the holding cell
3490                                 // now!
3491                                 match self.free_holding_cell_htlcs(logger) {
3492                                         Err(ChannelError::Close(msg)) => return Err(ChannelError::Close(msg)),
3493                                         Err(ChannelError::Warn(_)) | Err(ChannelError::Ignore(_)) | Err(ChannelError::CloseDelayBroadcast(_)) =>
3494                                                 panic!("Got non-channel-failing result from free_holding_cell_htlcs"),
3495                                         Ok((Some((commitment_update, monitor_update)), htlcs_to_fail)) => {
3496                                                 return Ok((resend_funding_locked, required_revoke, Some(commitment_update), Some(monitor_update), self.resend_order.clone(), htlcs_to_fail, shutdown_msg));
3497                                         },
3498                                         Ok((None, htlcs_to_fail)) => {
3499                                                 return Ok((resend_funding_locked, required_revoke, None, None, self.resend_order.clone(), htlcs_to_fail, shutdown_msg));
3500                                         },
3501                                 }
3502                         } else {
3503                                 return Ok((resend_funding_locked, required_revoke, None, None, self.resend_order.clone(), Vec::new(), shutdown_msg));
3504                         }
3505                 } else if msg.next_local_commitment_number == next_counterparty_commitment_number - 1 {
3506                         if required_revoke.is_some() {
3507                                 log_debug!(logger, "Reconnected channel {} with lost outbound RAA and lost remote commitment tx", log_bytes!(self.channel_id()));
3508                         } else {
3509                                 log_debug!(logger, "Reconnected channel {} with only lost remote commitment tx", log_bytes!(self.channel_id()));
3510                         }
3511
3512                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
3513                                 self.monitor_pending_commitment_signed = true;
3514                                 return Ok((resend_funding_locked, None, None, None, self.resend_order.clone(), Vec::new(), shutdown_msg));
3515                         }
3516
3517                         return Ok((resend_funding_locked, required_revoke, Some(self.get_last_commitment_update(logger)), None, self.resend_order.clone(), Vec::new(), shutdown_msg));
3518                 } else {
3519                         return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old remote commitment transaction".to_owned()));
3520                 }
3521         }
3522
3523         /// Calculates and returns our minimum and maximum closing transaction fee amounts, in whole
3524         /// satoshis. The amounts remain consistent unless a peer disconnects/reconnects or we restart,
3525         /// at which point they will be recalculated.
3526         fn calculate_closing_fee_limits<F: Deref>(&mut self, fee_estimator: &F) -> (u64, u64)
3527                 where F::Target: FeeEstimator
3528         {
3529                 if let Some((min, max)) = self.closing_fee_limits { return (min, max); }
3530
3531                 // Propose a range from our current Background feerate to our Normal feerate plus our
3532                 // force_close_avoidance_max_fee_satoshis.
3533                 // If we fail to come to consensus, we'll have to force-close.
3534                 let mut proposed_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
3535                 let normal_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
3536                 let mut proposed_max_feerate = if self.is_outbound() { normal_feerate } else { u32::max_value() };
3537
3538                 // The spec requires that (when the channel does not have anchors) we only send absolute
3539                 // channel fees no greater than the absolute channel fee on the current commitment
3540                 // transaction. It's unclear *which* commitment transaction this refers to, and there isn't
3541                 // very good reason to apply such a limit in any case. We don't bother doing so, risking
3542                 // some force-closure by old nodes, but we wanted to close the channel anyway.
3543
3544                 if let Some(target_feerate) = self.target_closing_feerate_sats_per_kw {
3545                         let min_feerate = if self.is_outbound() { target_feerate } else { cmp::min(self.feerate_per_kw, target_feerate) };
3546                         proposed_feerate = cmp::max(proposed_feerate, min_feerate);
3547                         proposed_max_feerate = cmp::max(proposed_max_feerate, min_feerate);
3548                 }
3549
3550                 // Note that technically we could end up with a lower minimum fee if one sides' balance is
3551                 // below our dust limit, causing the output to disappear. We don't bother handling this
3552                 // case, however, as this should only happen if a channel is closed before any (material)
3553                 // payments have been made on it. This may cause slight fee overpayment and/or failure to
3554                 // come to consensus with our counterparty on appropriate fees, however it should be a
3555                 // relatively rare case. We can revisit this later, though note that in order to determine
3556                 // if the funders' output is dust we have to know the absolute fee we're going to use.
3557                 let tx_weight = self.get_closing_transaction_weight(Some(&self.get_closing_scriptpubkey()), Some(self.counterparty_shutdown_scriptpubkey.as_ref().unwrap()));
3558                 let proposed_total_fee_satoshis = proposed_feerate as u64 * tx_weight / 1000;
3559                 let proposed_max_total_fee_satoshis = if self.is_outbound() {
3560                                 // We always add force_close_avoidance_max_fee_satoshis to our normal
3561                                 // feerate-calculated fee, but allow the max to be overridden if we're using a
3562                                 // target feerate-calculated fee.
3563                                 cmp::max(normal_feerate as u64 * tx_weight / 1000 + self.config.force_close_avoidance_max_fee_satoshis,
3564                                         proposed_max_feerate as u64 * tx_weight / 1000)
3565                         } else {
3566                                 self.channel_value_satoshis - (self.value_to_self_msat + 999) / 1000
3567                         };
3568
3569                 self.closing_fee_limits = Some((proposed_total_fee_satoshis, proposed_max_total_fee_satoshis));
3570                 self.closing_fee_limits.clone().unwrap()
3571         }
3572
3573         /// Returns true if we're ready to commence the closing_signed negotiation phase. This is true
3574         /// after both sides have exchanged a `shutdown` message and all HTLCs have been drained. At
3575         /// this point if we're the funder we should send the initial closing_signed, and in any case
3576         /// shutdown should complete within a reasonable timeframe.
3577         fn closing_negotiation_ready(&self) -> bool {
3578                 self.pending_inbound_htlcs.is_empty() && self.pending_outbound_htlcs.is_empty() &&
3579                         self.channel_state &
3580                                 (BOTH_SIDES_SHUTDOWN_MASK | ChannelState::AwaitingRemoteRevoke as u32 |
3581                                  ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)
3582                                 == BOTH_SIDES_SHUTDOWN_MASK &&
3583                         self.pending_update_fee.is_none()
3584         }
3585
3586         /// Checks if the closing_signed negotiation is making appropriate progress, possibly returning
3587         /// an Err if no progress is being made and the channel should be force-closed instead.
3588         /// Should be called on a one-minute timer.
3589         pub fn timer_check_closing_negotiation_progress(&mut self) -> Result<(), ChannelError> {
3590                 if self.closing_negotiation_ready() {
3591                         if self.closing_signed_in_flight {
3592                                 return Err(ChannelError::Close("closing_signed negotiation failed to finish within two timer ticks".to_owned()));
3593                         } else {
3594                                 self.closing_signed_in_flight = true;
3595                         }
3596                 }
3597                 Ok(())
3598         }
3599
3600         pub fn maybe_propose_closing_signed<F: Deref, L: Deref>(&mut self, fee_estimator: &F, logger: &L)
3601                 -> Result<(Option<msgs::ClosingSigned>, Option<Transaction>), ChannelError>
3602                 where F::Target: FeeEstimator, L::Target: Logger
3603         {
3604                 if self.last_sent_closing_fee.is_some() || !self.closing_negotiation_ready() {
3605                         return Ok((None, None));
3606                 }
3607
3608                 if !self.is_outbound() {
3609                         if let Some(msg) = &self.pending_counterparty_closing_signed.take() {
3610                                 return self.closing_signed(fee_estimator, &msg);
3611                         }
3612                         return Ok((None, None));
3613                 }
3614
3615                 let (our_min_fee, our_max_fee) = self.calculate_closing_fee_limits(fee_estimator);
3616
3617                 assert!(self.shutdown_scriptpubkey.is_some());
3618                 let (closing_tx, total_fee_satoshis) = self.build_closing_transaction(our_min_fee, false);
3619                 log_trace!(logger, "Proposing initial closing_signed for our counterparty with a fee range of {}-{} sat (with initial proposal {} sats)",
3620                         our_min_fee, our_max_fee, total_fee_satoshis);
3621
3622                 let sig = self.holder_signer
3623                         .sign_closing_transaction(&closing_tx, &self.secp_ctx)
3624                         .map_err(|()| ChannelError::Close("Failed to get signature for closing transaction.".to_owned()))?;
3625
3626                 self.last_sent_closing_fee = Some((total_fee_satoshis, sig.clone()));
3627                 Ok((Some(msgs::ClosingSigned {
3628                         channel_id: self.channel_id,
3629                         fee_satoshis: total_fee_satoshis,
3630                         signature: sig,
3631                         fee_range: Some(msgs::ClosingSignedFeeRange {
3632                                 min_fee_satoshis: our_min_fee,
3633                                 max_fee_satoshis: our_max_fee,
3634                         }),
3635                 }), None))
3636         }
3637
3638         pub fn shutdown<K: Deref>(
3639                 &mut self, keys_provider: &K, their_features: &InitFeatures, msg: &msgs::Shutdown
3640         ) -> Result<(Option<msgs::Shutdown>, Option<ChannelMonitorUpdate>, Vec<(HTLCSource, PaymentHash)>), ChannelError>
3641         where K::Target: KeysInterface<Signer = Signer>
3642         {
3643                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
3644                         return Err(ChannelError::Close("Peer sent shutdown when we needed a channel_reestablish".to_owned()));
3645                 }
3646                 if self.channel_state < ChannelState::FundingSent as u32 {
3647                         // Spec says we should fail the connection, not the channel, but that's nonsense, there
3648                         // are plenty of reasons you may want to fail a channel pre-funding, and spec says you
3649                         // can do that via error message without getting a connection fail anyway...
3650                         return Err(ChannelError::Close("Peer sent shutdown pre-funding generation".to_owned()));
3651                 }
3652                 for htlc in self.pending_inbound_htlcs.iter() {
3653                         if let InboundHTLCState::RemoteAnnounced(_) = htlc.state {
3654                                 return Err(ChannelError::Close("Got shutdown with remote pending HTLCs".to_owned()));
3655                         }
3656                 }
3657                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
3658
3659                 if !script::is_bolt2_compliant(&msg.scriptpubkey, their_features) {
3660                         return Err(ChannelError::Close(format!("Got a nonstandard scriptpubkey ({}) from remote peer", msg.scriptpubkey.to_bytes().to_hex())));
3661                 }
3662
3663                 if self.counterparty_shutdown_scriptpubkey.is_some() {
3664                         if Some(&msg.scriptpubkey) != self.counterparty_shutdown_scriptpubkey.as_ref() {
3665                                 return Err(ChannelError::Close(format!("Got shutdown request with a scriptpubkey ({}) which did not match their previous scriptpubkey.", msg.scriptpubkey.to_bytes().to_hex())));
3666                         }
3667                 } else {
3668                         self.counterparty_shutdown_scriptpubkey = Some(msg.scriptpubkey.clone());
3669                 }
3670
3671                 // If we have any LocalAnnounced updates we'll probably just get back an update_fail_htlc
3672                 // immediately after the commitment dance, but we can send a Shutdown because we won't send
3673                 // any further commitment updates after we set LocalShutdownSent.
3674                 let send_shutdown = (self.channel_state & ChannelState::LocalShutdownSent as u32) != ChannelState::LocalShutdownSent as u32;
3675
3676                 let update_shutdown_script = match self.shutdown_scriptpubkey {
3677                         Some(_) => false,
3678                         None => {
3679                                 assert!(send_shutdown);
3680                                 let shutdown_scriptpubkey = keys_provider.get_shutdown_scriptpubkey();
3681                                 if !shutdown_scriptpubkey.is_compatible(their_features) {
3682                                         return Err(ChannelError::Close(format!("Provided a scriptpubkey format not accepted by peer: {}", shutdown_scriptpubkey)));
3683                                 }
3684                                 self.shutdown_scriptpubkey = Some(shutdown_scriptpubkey);
3685                                 true
3686                         },
3687                 };
3688
3689                 // From here on out, we may not fail!
3690
3691                 self.channel_state |= ChannelState::RemoteShutdownSent as u32;
3692                 self.update_time_counter += 1;
3693
3694                 let monitor_update = if update_shutdown_script {
3695                         self.latest_monitor_update_id += 1;
3696                         Some(ChannelMonitorUpdate {
3697                                 update_id: self.latest_monitor_update_id,
3698                                 updates: vec![ChannelMonitorUpdateStep::ShutdownScript {
3699                                         scriptpubkey: self.get_closing_scriptpubkey(),
3700                                 }],
3701                         })
3702                 } else { None };
3703                 let shutdown = if send_shutdown {
3704                         Some(msgs::Shutdown {
3705                                 channel_id: self.channel_id,
3706                                 scriptpubkey: self.get_closing_scriptpubkey(),
3707                         })
3708                 } else { None };
3709
3710                 // We can't send our shutdown until we've committed all of our pending HTLCs, but the
3711                 // remote side is unlikely to accept any new HTLCs, so we go ahead and "free" any holding
3712                 // cell HTLCs and return them to fail the payment.
3713                 self.holding_cell_update_fee = None;
3714                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
3715                 self.holding_cell_htlc_updates.retain(|htlc_update| {
3716                         match htlc_update {
3717                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
3718                                         dropped_outbound_htlcs.push((source.clone(), payment_hash.clone()));
3719                                         false
3720                                 },
3721                                 _ => true
3722                         }
3723                 });
3724
3725                 self.channel_state |= ChannelState::LocalShutdownSent as u32;
3726                 self.update_time_counter += 1;
3727
3728                 Ok((shutdown, monitor_update, dropped_outbound_htlcs))
3729         }
3730
3731         fn build_signed_closing_transaction(&self, closing_tx: &ClosingTransaction, counterparty_sig: &Signature, sig: &Signature) -> Transaction {
3732                 let mut tx = closing_tx.trust().built_transaction().clone();
3733
3734                 tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
3735
3736                 let funding_key = self.get_holder_pubkeys().funding_pubkey.serialize();
3737                 let counterparty_funding_key = self.counterparty_funding_pubkey().serialize();
3738                 if funding_key[..] < counterparty_funding_key[..] {
3739                         tx.input[0].witness.push(sig.serialize_der().to_vec());
3740                         tx.input[0].witness.push(counterparty_sig.serialize_der().to_vec());
3741                 } else {
3742                         tx.input[0].witness.push(counterparty_sig.serialize_der().to_vec());
3743                         tx.input[0].witness.push(sig.serialize_der().to_vec());
3744                 }
3745                 tx.input[0].witness[1].push(SigHashType::All as u8);
3746                 tx.input[0].witness[2].push(SigHashType::All as u8);
3747
3748                 tx.input[0].witness.push(self.get_funding_redeemscript().into_bytes());
3749                 tx
3750         }
3751
3752         pub fn closing_signed<F: Deref>(&mut self, fee_estimator: &F, msg: &msgs::ClosingSigned) -> Result<(Option<msgs::ClosingSigned>, Option<Transaction>), ChannelError>
3753                 where F::Target: FeeEstimator
3754         {
3755                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != BOTH_SIDES_SHUTDOWN_MASK {
3756                         return Err(ChannelError::Close("Remote end sent us a closing_signed before both sides provided a shutdown".to_owned()));
3757                 }
3758                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
3759                         return Err(ChannelError::Close("Peer sent closing_signed when we needed a channel_reestablish".to_owned()));
3760                 }
3761                 if !self.pending_inbound_htlcs.is_empty() || !self.pending_outbound_htlcs.is_empty() {
3762                         return Err(ChannelError::Close("Remote end sent us a closing_signed while there were still pending HTLCs".to_owned()));
3763                 }
3764                 if msg.fee_satoshis > 21_000_000 * 1_0000_0000 { //this is required to stop potential overflow in build_closing_transaction
3765                         return Err(ChannelError::Close("Remote tried to send us a closing tx with > 21 million BTC fee".to_owned()));
3766                 }
3767
3768                 if self.is_outbound() && self.last_sent_closing_fee.is_none() {
3769                         return Err(ChannelError::Close("Remote tried to send a closing_signed when we were supposed to propose the first one".to_owned()));
3770                 }
3771
3772                 if self.channel_state & ChannelState::MonitorUpdateFailed as u32 != 0 {
3773                         self.pending_counterparty_closing_signed = Some(msg.clone());
3774                         return Ok((None, None));
3775                 }
3776
3777                 let funding_redeemscript = self.get_funding_redeemscript();
3778                 let (mut closing_tx, used_total_fee) = self.build_closing_transaction(msg.fee_satoshis, false);
3779                 if used_total_fee != msg.fee_satoshis {
3780                         return Err(ChannelError::Close(format!("Remote sent us a closing_signed with a fee other than the value they can claim. Fee in message: {}. Actual closing tx fee: {}", msg.fee_satoshis, used_total_fee)));
3781                 }
3782                 let sighash = closing_tx.trust().get_sighash_all(&funding_redeemscript, self.channel_value_satoshis);
3783
3784                 match self.secp_ctx.verify(&sighash, &msg.signature, &self.get_counterparty_pubkeys().funding_pubkey) {
3785                         Ok(_) => {},
3786                         Err(_e) => {
3787                                 // The remote end may have decided to revoke their output due to inconsistent dust
3788                                 // limits, so check for that case by re-checking the signature here.
3789                                 closing_tx = self.build_closing_transaction(msg.fee_satoshis, true).0;
3790                                 let sighash = closing_tx.trust().get_sighash_all(&funding_redeemscript, self.channel_value_satoshis);
3791                                 secp_check!(self.secp_ctx.verify(&sighash, &msg.signature, self.counterparty_funding_pubkey()), "Invalid closing tx signature from peer".to_owned());
3792                         },
3793                 };
3794
3795                 for outp in closing_tx.trust().built_transaction().output.iter() {
3796                         if !outp.script_pubkey.is_witness_program() && outp.value < MAX_STD_OUTPUT_DUST_LIMIT_SATOSHIS {
3797                                 return Err(ChannelError::Close("Remote sent us a closing_signed with a dust output. Always use segwit closing scripts!".to_owned()));
3798                         }
3799                 }
3800
3801                 assert!(self.shutdown_scriptpubkey.is_some());
3802                 if let Some((last_fee, sig)) = self.last_sent_closing_fee {
3803                         if last_fee == msg.fee_satoshis {
3804                                 let tx = self.build_signed_closing_transaction(&mut closing_tx, &msg.signature, &sig);
3805                                 self.channel_state = ChannelState::ShutdownComplete as u32;
3806                                 self.update_time_counter += 1;
3807                                 return Ok((None, Some(tx)));
3808                         }
3809                 }
3810
3811                 let (our_min_fee, our_max_fee) = self.calculate_closing_fee_limits(fee_estimator);
3812
3813                 macro_rules! propose_fee {
3814                         ($new_fee: expr) => {
3815                                 let (closing_tx, used_fee) = if $new_fee == msg.fee_satoshis {
3816                                         (closing_tx, $new_fee)
3817                                 } else {
3818                                         self.build_closing_transaction($new_fee, false)
3819                                 };
3820
3821                                 let sig = self.holder_signer
3822                                         .sign_closing_transaction(&closing_tx, &self.secp_ctx)
3823                                         .map_err(|_| ChannelError::Close("External signer refused to sign closing transaction".to_owned()))?;
3824
3825                                 let signed_tx = if $new_fee == msg.fee_satoshis {
3826                                         self.channel_state = ChannelState::ShutdownComplete as u32;
3827                                         self.update_time_counter += 1;
3828                                         let tx = self.build_signed_closing_transaction(&closing_tx, &msg.signature, &sig);
3829                                         Some(tx)
3830                                 } else { None };
3831
3832                                 self.last_sent_closing_fee = Some((used_fee, sig.clone()));
3833                                 return Ok((Some(msgs::ClosingSigned {
3834                                         channel_id: self.channel_id,
3835                                         fee_satoshis: used_fee,
3836                                         signature: sig,
3837                                         fee_range: Some(msgs::ClosingSignedFeeRange {
3838                                                 min_fee_satoshis: our_min_fee,
3839                                                 max_fee_satoshis: our_max_fee,
3840                                         }),
3841                                 }), signed_tx))
3842                         }
3843                 }
3844
3845                 if let Some(msgs::ClosingSignedFeeRange { min_fee_satoshis, max_fee_satoshis }) = msg.fee_range {
3846                         if msg.fee_satoshis < min_fee_satoshis || msg.fee_satoshis > max_fee_satoshis {
3847                                 return Err(ChannelError::Close(format!("Peer sent a bogus closing_signed - suggested fee of {} sat was not in their desired range of {} sat - {} sat", msg.fee_satoshis, min_fee_satoshis, max_fee_satoshis)));
3848                         }
3849                         if max_fee_satoshis < our_min_fee {
3850                                 return Err(ChannelError::Warn(format!("Unable to come to consensus about closing feerate, remote's max fee ({} sat) was smaller than our min fee ({} sat)", max_fee_satoshis, our_min_fee)));
3851                         }
3852                         if min_fee_satoshis > our_max_fee {
3853                                 return Err(ChannelError::Warn(format!("Unable to come to consensus about closing feerate, remote's min fee ({} sat) was greater than our max fee ({} sat)", min_fee_satoshis, our_max_fee)));
3854                         }
3855
3856                         if !self.is_outbound() {
3857                                 // They have to pay, so pick the highest fee in the overlapping range.
3858                                 // We should never set an upper bound aside from their full balance
3859                                 debug_assert_eq!(our_max_fee, self.channel_value_satoshis - (self.value_to_self_msat + 999) / 1000);
3860                                 propose_fee!(cmp::min(max_fee_satoshis, our_max_fee));
3861                         } else {
3862                                 if msg.fee_satoshis < our_min_fee || msg.fee_satoshis > our_max_fee {
3863                                         return Err(ChannelError::Close(format!("Peer sent a bogus closing_signed - suggested fee of {} sat was not in our desired range of {} sat - {} sat after we informed them of our range.",
3864                                                 msg.fee_satoshis, our_min_fee, our_max_fee)));
3865                                 }
3866                                 // The proposed fee is in our acceptable range, accept it and broadcast!
3867                                 propose_fee!(msg.fee_satoshis);
3868                         }
3869                 } else {
3870                         // Old fee style negotiation. We don't bother to enforce whether they are complying
3871                         // with the "making progress" requirements, we just comply and hope for the best.
3872                         if let Some((last_fee, _)) = self.last_sent_closing_fee {
3873                                 if msg.fee_satoshis > last_fee {
3874                                         if msg.fee_satoshis < our_max_fee {
3875                                                 propose_fee!(msg.fee_satoshis);
3876                                         } else if last_fee < our_max_fee {
3877                                                 propose_fee!(our_max_fee);
3878                                         } else {
3879                                                 return Err(ChannelError::Close(format!("Unable to come to consensus about closing feerate, remote wants something ({} sat) higher than our max fee ({} sat)", msg.fee_satoshis, our_max_fee)));
3880                                         }
3881                                 } else {
3882                                         if msg.fee_satoshis > our_min_fee {
3883                                                 propose_fee!(msg.fee_satoshis);
3884                                         } else if last_fee > our_min_fee {
3885                                                 propose_fee!(our_min_fee);
3886                                         } else {
3887                                                 return Err(ChannelError::Close(format!("Unable to come to consensus about closing feerate, remote wants something ({} sat) lower than our min fee ({} sat)", msg.fee_satoshis, our_min_fee)));
3888                                         }
3889                                 }
3890                         } else {
3891                                 if msg.fee_satoshis < our_min_fee {
3892                                         propose_fee!(our_min_fee);
3893                                 } else if msg.fee_satoshis > our_max_fee {
3894                                         propose_fee!(our_max_fee);
3895                                 } else {
3896                                         propose_fee!(msg.fee_satoshis);
3897                                 }
3898                         }
3899                 }
3900         }
3901
3902         // Public utilities:
3903
3904         pub fn channel_id(&self) -> [u8; 32] {
3905                 self.channel_id
3906         }
3907
3908         pub fn minimum_depth(&self) -> Option<u32> {
3909                 self.minimum_depth
3910         }
3911
3912         /// Gets the "user_id" value passed into the construction of this channel. It has no special
3913         /// meaning and exists only to allow users to have a persistent identifier of a channel.
3914         pub fn get_user_id(&self) -> u64 {
3915                 self.user_id
3916         }
3917
3918         /// Guaranteed to be Some after both FundingLocked messages have been exchanged (and, thus,
3919         /// is_usable() returns true).
3920         /// Allowed in any state (including after shutdown)
3921         pub fn get_short_channel_id(&self) -> Option<u64> {
3922                 self.short_channel_id
3923         }
3924
3925         /// Returns the funding_txo we either got from our peer, or were given by
3926         /// get_outbound_funding_created.
3927         pub fn get_funding_txo(&self) -> Option<OutPoint> {
3928                 self.channel_transaction_parameters.funding_outpoint
3929         }
3930
3931         fn get_holder_selected_contest_delay(&self) -> u16 {
3932                 self.channel_transaction_parameters.holder_selected_contest_delay
3933         }
3934
3935         fn get_holder_pubkeys(&self) -> &ChannelPublicKeys {
3936                 &self.channel_transaction_parameters.holder_pubkeys
3937         }
3938
3939         pub fn get_counterparty_selected_contest_delay(&self) -> Option<u16> {
3940                 self.channel_transaction_parameters.counterparty_parameters
3941                         .as_ref().map(|params| params.selected_contest_delay)
3942         }
3943
3944         fn get_counterparty_pubkeys(&self) -> &ChannelPublicKeys {
3945                 &self.channel_transaction_parameters.counterparty_parameters.as_ref().unwrap().pubkeys
3946         }
3947
3948         /// Allowed in any state (including after shutdown)
3949         pub fn get_counterparty_node_id(&self) -> PublicKey {
3950                 self.counterparty_node_id
3951         }
3952
3953         /// Allowed in any state (including after shutdown)
3954         #[cfg(test)]
3955         pub fn get_holder_htlc_minimum_msat(&self) -> u64 {
3956                 self.holder_htlc_minimum_msat
3957         }
3958
3959         /// Allowed in any state (including after shutdown)
3960         pub fn get_announced_htlc_max_msat(&self) -> u64 {
3961                 return cmp::min(
3962                         // Upper bound by capacity. We make it a bit less than full capacity to prevent attempts
3963                         // to use full capacity. This is an effort to reduce routing failures, because in many cases
3964                         // channel might have been used to route very small values (either by honest users or as DoS).
3965                         self.channel_value_satoshis * 1000 * 9 / 10,
3966
3967                         Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis)
3968                 );
3969         }
3970
3971         /// Allowed in any state (including after shutdown)
3972         pub fn get_counterparty_htlc_minimum_msat(&self) -> u64 {
3973                 self.counterparty_htlc_minimum_msat
3974         }
3975
3976         pub fn get_value_satoshis(&self) -> u64 {
3977                 self.channel_value_satoshis
3978         }
3979
3980         pub fn get_fee_proportional_millionths(&self) -> u32 {
3981                 self.config.forwarding_fee_proportional_millionths
3982         }
3983
3984         pub fn get_cltv_expiry_delta(&self) -> u16 {
3985                 cmp::max(self.config.cltv_expiry_delta, MIN_CLTV_EXPIRY_DELTA)
3986         }
3987
3988         pub fn get_max_dust_htlc_exposure_msat(&self) -> u64 {
3989                 self.config.max_dust_htlc_exposure_msat
3990         }
3991
3992         pub fn get_feerate(&self) -> u32 {
3993                 self.feerate_per_kw
3994         }
3995
3996         pub fn get_dust_buffer_feerate(&self, outbound_feerate_update: Option<u32>) -> u32 {
3997                 // When calculating our exposure to dust HTLCs, we assume that the channel feerate
3998                 // may, at any point, increase by at least 10 sat/vB (i.e 2530 sat/kWU) or 25%,
3999                 // whichever is higher. This ensures that we aren't suddenly exposed to significantly
4000                 // more dust balance if the feerate increases when we have several HTLCs pending
4001                 // which are near the dust limit.
4002                 let mut feerate_per_kw = self.feerate_per_kw;
4003                 // If there's a pending update fee, use it to ensure we aren't under-estimating
4004                 // potential feerate updates coming soon.
4005                 if let Some((feerate, _)) = self.pending_update_fee {
4006                         feerate_per_kw = cmp::max(feerate_per_kw, feerate);
4007                 }
4008                 if let Some(feerate) = outbound_feerate_update {
4009                         feerate_per_kw = cmp::max(feerate_per_kw, feerate);
4010                 }
4011                 cmp::max(2530, feerate_per_kw * 1250 / 1000)
4012         }
4013
4014         pub fn get_cur_holder_commitment_transaction_number(&self) -> u64 {
4015                 self.cur_holder_commitment_transaction_number + 1
4016         }
4017
4018         pub fn get_cur_counterparty_commitment_transaction_number(&self) -> u64 {
4019                 self.cur_counterparty_commitment_transaction_number + 1 - if self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32) != 0 { 1 } else { 0 }
4020         }
4021
4022         pub fn get_revoked_counterparty_commitment_transaction_number(&self) -> u64 {
4023                 self.cur_counterparty_commitment_transaction_number + 2
4024         }
4025
4026         #[cfg(test)]
4027         pub fn get_signer(&self) -> &Signer {
4028                 &self.holder_signer
4029         }
4030
4031         #[cfg(test)]
4032         pub fn get_value_stat(&self) -> ChannelValueStat {
4033                 ChannelValueStat {
4034                         value_to_self_msat: self.value_to_self_msat,
4035                         channel_value_msat: self.channel_value_satoshis * 1000,
4036                         channel_reserve_msat: self.counterparty_selected_channel_reserve_satoshis.unwrap() * 1000,
4037                         pending_outbound_htlcs_amount_msat: self.pending_outbound_htlcs.iter().map(|ref h| h.amount_msat).sum::<u64>(),
4038                         pending_inbound_htlcs_amount_msat: self.pending_inbound_htlcs.iter().map(|ref h| h.amount_msat).sum::<u64>(),
4039                         holding_cell_outbound_amount_msat: {
4040                                 let mut res = 0;
4041                                 for h in self.holding_cell_htlc_updates.iter() {
4042                                         match h {
4043                                                 &HTLCUpdateAwaitingACK::AddHTLC{amount_msat, .. } => {
4044                                                         res += amount_msat;
4045                                                 }
4046                                                 _ => {}
4047                                         }
4048                                 }
4049                                 res
4050                         },
4051                         counterparty_max_htlc_value_in_flight_msat: self.counterparty_max_htlc_value_in_flight_msat,
4052                         counterparty_dust_limit_msat: self.counterparty_dust_limit_satoshis * 1000,
4053                 }
4054         }
4055
4056         /// Allowed in any state (including after shutdown)
4057         pub fn get_update_time_counter(&self) -> u32 {
4058                 self.update_time_counter
4059         }
4060
4061         pub fn get_latest_monitor_update_id(&self) -> u64 {
4062                 self.latest_monitor_update_id
4063         }
4064
4065         pub fn should_announce(&self) -> bool {
4066                 self.config.announced_channel
4067         }
4068
4069         pub fn is_outbound(&self) -> bool {
4070                 self.channel_transaction_parameters.is_outbound_from_holder
4071         }
4072
4073         /// Gets the fee we'd want to charge for adding an HTLC output to this Channel
4074         /// Allowed in any state (including after shutdown)
4075         pub fn get_outbound_forwarding_fee_base_msat(&self) -> u32 {
4076                 self.config.forwarding_fee_base_msat
4077         }
4078
4079         /// Returns true if we've ever received a message from the remote end for this Channel
4080         pub fn have_received_message(&self) -> bool {
4081                 self.channel_state > (ChannelState::OurInitSent as u32)
4082         }
4083
4084         /// Returns true if this channel is fully established and not known to be closing.
4085         /// Allowed in any state (including after shutdown)
4086         pub fn is_usable(&self) -> bool {
4087                 let mask = ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK;
4088                 (self.channel_state & mask) == (ChannelState::ChannelFunded as u32)
4089         }
4090
4091         /// Returns true if this channel is currently available for use. This is a superset of
4092         /// is_usable() and considers things like the channel being temporarily disabled.
4093         /// Allowed in any state (including after shutdown)
4094         pub fn is_live(&self) -> bool {
4095                 self.is_usable() && (self.channel_state & (ChannelState::PeerDisconnected as u32) == 0)
4096         }
4097
4098         /// Returns true if this channel has been marked as awaiting a monitor update to move forward.
4099         /// Allowed in any state (including after shutdown)
4100         pub fn is_awaiting_monitor_update(&self) -> bool {
4101                 (self.channel_state & ChannelState::MonitorUpdateFailed as u32) != 0
4102         }
4103
4104         /// Returns true if funding_created was sent/received.
4105         pub fn is_funding_initiated(&self) -> bool {
4106                 self.channel_state >= ChannelState::FundingSent as u32
4107         }
4108
4109         /// Returns true if our peer has either initiated or agreed to shut down the channel.
4110         pub fn received_shutdown(&self) -> bool {
4111                 (self.channel_state & ChannelState::RemoteShutdownSent as u32) != 0
4112         }
4113
4114         /// Returns true if we either initiated or agreed to shut down the channel.
4115         pub fn sent_shutdown(&self) -> bool {
4116                 (self.channel_state & ChannelState::LocalShutdownSent as u32) != 0
4117         }
4118
4119         /// Returns true if this channel is fully shut down. True here implies that no further actions
4120         /// may/will be taken on this channel, and thus this object should be freed. Any future changes
4121         /// will be handled appropriately by the chain monitor.
4122         pub fn is_shutdown(&self) -> bool {
4123                 if (self.channel_state & ChannelState::ShutdownComplete as u32) == ChannelState::ShutdownComplete as u32  {
4124                         assert!(self.channel_state == ChannelState::ShutdownComplete as u32);
4125                         true
4126                 } else { false }
4127         }
4128
4129         pub fn channel_update_status(&self) -> ChannelUpdateStatus {
4130                 self.channel_update_status
4131         }
4132
4133         pub fn set_channel_update_status(&mut self, status: ChannelUpdateStatus) {
4134                 self.channel_update_status = status;
4135         }
4136
4137         fn check_get_funding_locked(&mut self, height: u32) -> Option<msgs::FundingLocked> {
4138                 if self.funding_tx_confirmation_height == 0 {
4139                         return None;
4140                 }
4141
4142                 let funding_tx_confirmations = height as i64 - self.funding_tx_confirmation_height as i64 + 1;
4143                 if funding_tx_confirmations <= 0 {
4144                         self.funding_tx_confirmation_height = 0;
4145                 }
4146
4147                 if funding_tx_confirmations < self.minimum_depth.unwrap_or(0) as i64 {
4148                         return None;
4149                 }
4150
4151                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
4152                 let need_commitment_update = if non_shutdown_state == ChannelState::FundingSent as u32 {
4153                         self.channel_state |= ChannelState::OurFundingLocked as u32;
4154                         true
4155                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32) {
4156                         self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
4157                         self.update_time_counter += 1;
4158                         true
4159                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) {
4160                         // We got a reorg but not enough to trigger a force close, just ignore.
4161                         false
4162                 } else if self.channel_state < ChannelState::ChannelFunded as u32 {
4163                         panic!("Started confirming a channel in a state pre-FundingSent?: {}", self.channel_state);
4164                 } else {
4165                         // We got a reorg but not enough to trigger a force close, just ignore.
4166                         false
4167                 };
4168
4169                 if need_commitment_update {
4170                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) == 0 {
4171                                 let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
4172                                 return Some(msgs::FundingLocked {
4173                                         channel_id: self.channel_id,
4174                                         next_per_commitment_point,
4175                                 });
4176                         } else {
4177                                 self.monitor_pending_funding_locked = true;
4178                         }
4179                 }
4180                 None
4181         }
4182
4183         /// When a transaction is confirmed, we check whether it is or spends the funding transaction
4184         /// In the first case, we store the confirmation height and calculating the short channel id.
4185         /// In the second, we simply return an Err indicating we need to be force-closed now.
4186         pub fn transactions_confirmed<L: Deref>(&mut self, block_hash: &BlockHash, height: u32, txdata: &TransactionData, logger: &L)
4187         -> Result<Option<msgs::FundingLocked>, ClosureReason> where L::Target: Logger {
4188                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
4189                 for &(index_in_block, tx) in txdata.iter() {
4190                         if let Some(funding_txo) = self.get_funding_txo() {
4191                                 // If we haven't yet sent a funding_locked, but are in FundingSent (ignoring
4192                                 // whether they've sent a funding_locked or not), check if we should send one.
4193                                 if non_shutdown_state & !(ChannelState::TheirFundingLocked as u32) == ChannelState::FundingSent as u32 {
4194                                         if tx.txid() == funding_txo.txid {
4195                                                 let txo_idx = funding_txo.index as usize;
4196                                                 if txo_idx >= tx.output.len() || tx.output[txo_idx].script_pubkey != self.get_funding_redeemscript().to_v0_p2wsh() ||
4197                                                                 tx.output[txo_idx].value != self.channel_value_satoshis {
4198                                                         if self.is_outbound() {
4199                                                                 // If we generated the funding transaction and it doesn't match what it
4200                                                                 // should, the client is really broken and we should just panic and
4201                                                                 // tell them off. That said, because hash collisions happen with high
4202                                                                 // probability in fuzztarget mode, if we're fuzzing we just close the
4203                                                                 // channel and move on.
4204                                                                 #[cfg(not(feature = "fuzztarget"))]
4205                                                                 panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
4206                                                         }
4207                                                         self.update_time_counter += 1;
4208                                                         let err_reason = "funding tx had wrong script/value or output index";
4209                                                         return Err(ClosureReason::ProcessingError { err: err_reason.to_owned() });
4210                                                 } else {
4211                                                         if self.is_outbound() {
4212                                                                 for input in tx.input.iter() {
4213                                                                         if input.witness.is_empty() {
4214                                                                                 // We generated a malleable funding transaction, implying we've
4215                                                                                 // just exposed ourselves to funds loss to our counterparty.
4216                                                                                 #[cfg(not(feature = "fuzztarget"))]
4217                                                                                 panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
4218                                                                         }
4219                                                                 }
4220                                                         }
4221                                                         self.funding_tx_confirmation_height = height;
4222                                                         self.funding_tx_confirmed_in = Some(*block_hash);
4223                                                         self.short_channel_id = match scid_from_parts(height as u64, index_in_block as u64, txo_idx as u64) {
4224                                                                 Ok(scid) => Some(scid),
4225                                                                 Err(_) => panic!("Block was bogus - either height was > 16 million, had > 16 million transactions, or had > 65k outputs"),
4226                                                         }
4227                                                 }
4228                                         }
4229                                         // If we allow 1-conf funding, we may need to check for funding_locked here and
4230                                         // send it immediately instead of waiting for a best_block_updated call (which
4231                                         // may have already happened for this block).
4232                                         if let Some(funding_locked) = self.check_get_funding_locked(height) {
4233                                                 log_info!(logger, "Sending a funding_locked to our peer for channel {}", log_bytes!(self.channel_id));
4234                                                 return Ok(Some(funding_locked));
4235                                         }
4236                                 }
4237                                 for inp in tx.input.iter() {
4238                                         if inp.previous_output == funding_txo.into_bitcoin_outpoint() {
4239                                                 log_info!(logger, "Detected channel-closing tx {} spending {}:{}, closing channel {}", tx.txid(), inp.previous_output.txid, inp.previous_output.vout, log_bytes!(self.channel_id()));
4240                                                 return Err(ClosureReason::CommitmentTxConfirmed);
4241                                         }
4242                                 }
4243                         }
4244                 }
4245                 Ok(None)
4246         }
4247
4248         /// When a new block is connected, we check the height of the block against outbound holding
4249         /// cell HTLCs in case we need to give up on them prematurely and time them out. Everything
4250         /// else (e.g. commitment transaction broadcasts, HTLC transaction broadcasting, etc) is
4251         /// handled by the ChannelMonitor.
4252         ///
4253         /// If we return Err, the channel may have been closed, at which point the standard
4254         /// requirements apply - no calls may be made except those explicitly stated to be allowed
4255         /// post-shutdown.
4256         ///
4257         /// May return some HTLCs (and their payment_hash) which have timed out and should be failed
4258         /// back.
4259         pub fn best_block_updated<L: Deref>(&mut self, height: u32, highest_header_time: u32, logger: &L)
4260         -> Result<(Option<msgs::FundingLocked>, Vec<(HTLCSource, PaymentHash)>), ClosureReason> where L::Target: Logger {
4261                 let mut timed_out_htlcs = Vec::new();
4262                 // This mirrors the check in ChannelManager::decode_update_add_htlc_onion, refusing to
4263                 // forward an HTLC when our counterparty should almost certainly just fail it for expiring
4264                 // ~now.
4265                 let unforwarded_htlc_cltv_limit = height + LATENCY_GRACE_PERIOD_BLOCKS;
4266                 self.holding_cell_htlc_updates.retain(|htlc_update| {
4267                         match htlc_update {
4268                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, ref cltv_expiry, .. } => {
4269                                         if *cltv_expiry <= unforwarded_htlc_cltv_limit {
4270                                                 timed_out_htlcs.push((source.clone(), payment_hash.clone()));
4271                                                 false
4272                                         } else { true }
4273                                 },
4274                                 _ => true
4275                         }
4276                 });
4277
4278                 self.update_time_counter = cmp::max(self.update_time_counter, highest_header_time);
4279
4280                 if let Some(funding_locked) = self.check_get_funding_locked(height) {
4281                         log_info!(logger, "Sending a funding_locked to our peer for channel {}", log_bytes!(self.channel_id));
4282                         return Ok((Some(funding_locked), timed_out_htlcs));
4283                 }
4284
4285                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
4286                 if non_shutdown_state >= ChannelState::ChannelFunded as u32 ||
4287                    (non_shutdown_state & ChannelState::OurFundingLocked as u32) == ChannelState::OurFundingLocked as u32 {
4288                         let mut funding_tx_confirmations = height as i64 - self.funding_tx_confirmation_height as i64 + 1;
4289                         if self.funding_tx_confirmation_height == 0 {
4290                                 // Note that check_get_funding_locked may reset funding_tx_confirmation_height to
4291                                 // zero if it has been reorged out, however in either case, our state flags
4292                                 // indicate we've already sent a funding_locked
4293                                 funding_tx_confirmations = 0;
4294                         }
4295
4296                         // If we've sent funding_locked (or have both sent and received funding_locked), and
4297                         // the funding transaction's confirmation count has dipped below minimum_depth / 2,
4298                         // close the channel and hope we can get the latest state on chain (because presumably
4299                         // the funding transaction is at least still in the mempool of most nodes).
4300                         if funding_tx_confirmations < self.minimum_depth.unwrap() as i64 / 2 {
4301                                 let err_reason = format!("Funding transaction was un-confirmed. Locked at {} confs, now have {} confs.",
4302                                         self.minimum_depth.unwrap(), funding_tx_confirmations);
4303                                 return Err(ClosureReason::ProcessingError { err: err_reason });
4304                         }
4305                 } else if !self.is_outbound() && self.funding_tx_confirmed_in.is_none() &&
4306                                 height >= self.channel_creation_height + FUNDING_CONF_DEADLINE_BLOCKS {
4307                         log_info!(logger, "Closing channel {} due to funding timeout", log_bytes!(self.channel_id));
4308                         // If funding_tx_confirmed_in is unset, the channel must not be active
4309                         assert!(non_shutdown_state <= ChannelState::ChannelFunded as u32);
4310                         assert_eq!(non_shutdown_state & ChannelState::OurFundingLocked as u32, 0);
4311                         return Err(ClosureReason::FundingTimedOut);
4312                 }
4313
4314                 Ok((None, timed_out_htlcs))
4315         }
4316
4317         /// Indicates the funding transaction is no longer confirmed in the main chain. This may
4318         /// force-close the channel, but may also indicate a harmless reorganization of a block or two
4319         /// before the channel has reached funding_locked and we can just wait for more blocks.
4320         pub fn funding_transaction_unconfirmed<L: Deref>(&mut self, logger: &L) -> Result<(), ClosureReason> where L::Target: Logger {
4321                 if self.funding_tx_confirmation_height != 0 {
4322                         // We handle the funding disconnection by calling best_block_updated with a height one
4323                         // below where our funding was connected, implying a reorg back to conf_height - 1.
4324                         let reorg_height = self.funding_tx_confirmation_height - 1;
4325                         // We use the time field to bump the current time we set on channel updates if its
4326                         // larger. If we don't know that time has moved forward, we can just set it to the last
4327                         // time we saw and it will be ignored.
4328                         let best_time = self.update_time_counter;
4329                         match self.best_block_updated(reorg_height, best_time, logger) {
4330                                 Ok((funding_locked, timed_out_htlcs)) => {
4331                                         assert!(funding_locked.is_none(), "We can't generate a funding with 0 confirmations?");
4332                                         assert!(timed_out_htlcs.is_empty(), "We can't have accepted HTLCs with a timeout before our funding confirmation?");
4333                                         Ok(())
4334                                 },
4335                                 Err(e) => Err(e)
4336                         }
4337                 } else {
4338                         // We never learned about the funding confirmation anyway, just ignore
4339                         Ok(())
4340                 }
4341         }
4342
4343         // Methods to get unprompted messages to send to the remote end (or where we already returned
4344         // something in the handler for the message that prompted this message):
4345
4346         pub fn get_open_channel(&self, chain_hash: BlockHash) -> msgs::OpenChannel {
4347                 if !self.is_outbound() {
4348                         panic!("Tried to open a channel for an inbound channel?");
4349                 }
4350                 if self.channel_state != ChannelState::OurInitSent as u32 {
4351                         panic!("Cannot generate an open_channel after we've moved forward");
4352                 }
4353
4354                 if self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
4355                         panic!("Tried to send an open_channel for a channel that has already advanced");
4356                 }
4357
4358                 let first_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
4359                 let keys = self.get_holder_pubkeys();
4360
4361                 msgs::OpenChannel {
4362                         chain_hash,
4363                         temporary_channel_id: self.channel_id,
4364                         funding_satoshis: self.channel_value_satoshis,
4365                         push_msat: self.channel_value_satoshis * 1000 - self.value_to_self_msat,
4366                         dust_limit_satoshis: self.holder_dust_limit_satoshis,
4367                         max_htlc_value_in_flight_msat: Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis),
4368                         channel_reserve_satoshis: Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis),
4369                         htlc_minimum_msat: self.holder_htlc_minimum_msat,
4370                         feerate_per_kw: self.feerate_per_kw as u32,
4371                         to_self_delay: self.get_holder_selected_contest_delay(),
4372                         max_accepted_htlcs: OUR_MAX_HTLCS,
4373                         funding_pubkey: keys.funding_pubkey,
4374                         revocation_basepoint: keys.revocation_basepoint,
4375                         payment_point: keys.payment_point,
4376                         delayed_payment_basepoint: keys.delayed_payment_basepoint,
4377                         htlc_basepoint: keys.htlc_basepoint,
4378                         first_per_commitment_point,
4379                         channel_flags: if self.config.announced_channel {1} else {0},
4380                         shutdown_scriptpubkey: OptionalField::Present(match &self.shutdown_scriptpubkey {
4381                                 Some(script) => script.clone().into_inner(),
4382                                 None => Builder::new().into_script(),
4383                         }),
4384                         channel_type: Some(self.channel_type.clone()),
4385                 }
4386         }
4387
4388         pub fn get_accept_channel(&self) -> msgs::AcceptChannel {
4389                 if self.is_outbound() {
4390                         panic!("Tried to send accept_channel for an outbound channel?");
4391                 }
4392                 if self.channel_state != (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32) {
4393                         panic!("Tried to send accept_channel after channel had moved forward");
4394                 }
4395                 if self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
4396                         panic!("Tried to send an accept_channel for a channel that has already advanced");
4397                 }
4398
4399                 let first_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
4400                 let keys = self.get_holder_pubkeys();
4401
4402                 msgs::AcceptChannel {
4403                         temporary_channel_id: self.channel_id,
4404                         dust_limit_satoshis: self.holder_dust_limit_satoshis,
4405                         max_htlc_value_in_flight_msat: Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis),
4406                         channel_reserve_satoshis: Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis),
4407                         htlc_minimum_msat: self.holder_htlc_minimum_msat,
4408                         minimum_depth: self.minimum_depth.unwrap(),
4409                         to_self_delay: self.get_holder_selected_contest_delay(),
4410                         max_accepted_htlcs: OUR_MAX_HTLCS,
4411                         funding_pubkey: keys.funding_pubkey,
4412                         revocation_basepoint: keys.revocation_basepoint,
4413                         payment_point: keys.payment_point,
4414                         delayed_payment_basepoint: keys.delayed_payment_basepoint,
4415                         htlc_basepoint: keys.htlc_basepoint,
4416                         first_per_commitment_point,
4417                         shutdown_scriptpubkey: OptionalField::Present(match &self.shutdown_scriptpubkey {
4418                                 Some(script) => script.clone().into_inner(),
4419                                 None => Builder::new().into_script(),
4420                         }),
4421                 }
4422         }
4423
4424         /// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
4425         fn get_outbound_funding_created_signature<L: Deref>(&mut self, logger: &L) -> Result<Signature, ChannelError> where L::Target: Logger {
4426                 let counterparty_keys = self.build_remote_transaction_keys()?;
4427                 let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).0;
4428                 Ok(self.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, &self.secp_ctx)
4429                                 .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0)
4430         }
4431
4432         /// Updates channel state with knowledge of the funding transaction's txid/index, and generates
4433         /// a funding_created message for the remote peer.
4434         /// Panics if called at some time other than immediately after initial handshake, if called twice,
4435         /// or if called on an inbound channel.
4436         /// Note that channel_id changes during this call!
4437         /// Do NOT broadcast the funding transaction until after a successful funding_signed call!
4438         /// If an Err is returned, it is a ChannelError::Close.
4439         pub fn get_outbound_funding_created<L: Deref>(&mut self, funding_transaction: Transaction, funding_txo: OutPoint, logger: &L) -> Result<msgs::FundingCreated, ChannelError> where L::Target: Logger {
4440                 if !self.is_outbound() {
4441                         panic!("Tried to create outbound funding_created message on an inbound channel!");
4442                 }
4443                 if self.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
4444                         panic!("Tried to get a funding_created messsage at a time other than immediately after initial handshake completion (or tried to get funding_created twice)");
4445                 }
4446                 if self.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
4447                                 self.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
4448                                 self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
4449                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
4450                 }
4451
4452                 self.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
4453                 self.holder_signer.ready_channel(&self.channel_transaction_parameters);
4454
4455                 let signature = match self.get_outbound_funding_created_signature(logger) {
4456                         Ok(res) => res,
4457                         Err(e) => {
4458                                 log_error!(logger, "Got bad signatures: {:?}!", e);
4459                                 self.channel_transaction_parameters.funding_outpoint = None;
4460                                 return Err(e);
4461                         }
4462                 };
4463
4464                 let temporary_channel_id = self.channel_id;
4465
4466                 // Now that we're past error-generating stuff, update our local state:
4467
4468                 self.channel_state = ChannelState::FundingCreated as u32;
4469                 self.channel_id = funding_txo.to_channel_id();
4470                 self.funding_transaction = Some(funding_transaction);
4471
4472                 Ok(msgs::FundingCreated {
4473                         temporary_channel_id,
4474                         funding_txid: funding_txo.txid,
4475                         funding_output_index: funding_txo.index,
4476                         signature
4477                 })
4478         }
4479
4480         /// Gets an UnsignedChannelAnnouncement, as well as a signature covering it using our
4481         /// bitcoin_key, if available, for this channel. The channel must be publicly announceable and
4482         /// available for use (have exchanged FundingLocked messages in both directions). Should be used
4483         /// for both loose and in response to an AnnouncementSignatures message from the remote peer.
4484         /// Will only fail if we're not in a state where channel_announcement may be sent (including
4485         /// closing).
4486         /// Note that the "channel must be funded" requirement is stricter than BOLT 7 requires - see
4487         /// https://github.com/lightningnetwork/lightning-rfc/issues/468
4488         ///
4489         /// This will only return ChannelError::Ignore upon failure.
4490         pub fn get_channel_announcement(&self, node_id: PublicKey, chain_hash: BlockHash) -> Result<(msgs::UnsignedChannelAnnouncement, Signature), ChannelError> {
4491                 if !self.config.announced_channel {
4492                         return Err(ChannelError::Ignore("Channel is not available for public announcements".to_owned()));
4493                 }
4494                 if self.channel_state & (ChannelState::ChannelFunded as u32) == 0 {
4495                         return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement until the channel funding has been locked".to_owned()));
4496                 }
4497                 if (self.channel_state & (ChannelState::LocalShutdownSent as u32 | ChannelState::ShutdownComplete as u32)) != 0 {
4498                         return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement once the channel is closing".to_owned()));
4499                 }
4500
4501                 let were_node_one = node_id.serialize()[..] < self.counterparty_node_id.serialize()[..];
4502
4503                 let msg = msgs::UnsignedChannelAnnouncement {
4504                         features: ChannelFeatures::known(),
4505                         chain_hash,
4506                         short_channel_id: self.get_short_channel_id().unwrap(),
4507                         node_id_1: if were_node_one { node_id } else { self.get_counterparty_node_id() },
4508                         node_id_2: if were_node_one { self.get_counterparty_node_id() } else { node_id },
4509                         bitcoin_key_1: if were_node_one { self.get_holder_pubkeys().funding_pubkey } else { self.counterparty_funding_pubkey().clone() },
4510                         bitcoin_key_2: if were_node_one { self.counterparty_funding_pubkey().clone() } else { self.get_holder_pubkeys().funding_pubkey },
4511                         excess_data: Vec::new(),
4512                 };
4513
4514                 let sig = self.holder_signer.sign_channel_announcement(&msg, &self.secp_ctx)
4515                         .map_err(|_| ChannelError::Ignore("Signer rejected channel_announcement".to_owned()))?;
4516
4517                 Ok((msg, sig))
4518         }
4519
4520         /// Signs the given channel announcement, returning a ChannelError::Ignore if no keys are
4521         /// available.
4522         fn sign_channel_announcement(&self, our_node_secret: &SecretKey, our_node_id: PublicKey, msghash: secp256k1::Message, announcement: msgs::UnsignedChannelAnnouncement, our_bitcoin_sig: Signature) -> Result<msgs::ChannelAnnouncement, ChannelError> {
4523                 if let Some((their_node_sig, their_bitcoin_sig)) = self.announcement_sigs {
4524                         let were_node_one = announcement.node_id_1 == our_node_id;
4525
4526                         let our_node_sig = self.secp_ctx.sign(&msghash, our_node_secret);
4527                         Ok(msgs::ChannelAnnouncement {
4528                                 node_signature_1: if were_node_one { our_node_sig } else { their_node_sig },
4529                                 node_signature_2: if were_node_one { their_node_sig } else { our_node_sig },
4530                                 bitcoin_signature_1: if were_node_one { our_bitcoin_sig } else { their_bitcoin_sig },
4531                                 bitcoin_signature_2: if were_node_one { their_bitcoin_sig } else { our_bitcoin_sig },
4532                                 contents: announcement,
4533                         })
4534                 } else {
4535                         Err(ChannelError::Ignore("Attempted to sign channel announcement before we'd received announcement_signatures".to_string()))
4536                 }
4537         }
4538
4539         /// Processes an incoming announcement_signatures message, providing a fully-signed
4540         /// channel_announcement message which we can broadcast and storing our counterparty's
4541         /// signatures for later reconstruction/rebroadcast of the channel_announcement.
4542         pub fn announcement_signatures(&mut self, our_node_secret: &SecretKey, our_node_id: PublicKey, chain_hash: BlockHash, msg: &msgs::AnnouncementSignatures) -> Result<msgs::ChannelAnnouncement, ChannelError> {
4543                 let (announcement, our_bitcoin_sig) = self.get_channel_announcement(our_node_id.clone(), chain_hash)?;
4544
4545                 let msghash = hash_to_message!(&Sha256d::hash(&announcement.encode()[..])[..]);
4546
4547                 if self.secp_ctx.verify(&msghash, &msg.node_signature, &self.get_counterparty_node_id()).is_err() {
4548                         return Err(ChannelError::Close(format!(
4549                                 "Bad announcement_signatures. Failed to verify node_signature. UnsignedChannelAnnouncement used for verification is {:?}. their_node_key is {:?}",
4550                                  &announcement, self.get_counterparty_node_id())));
4551                 }
4552                 if self.secp_ctx.verify(&msghash, &msg.bitcoin_signature, self.counterparty_funding_pubkey()).is_err() {
4553                         return Err(ChannelError::Close(format!(
4554                                 "Bad announcement_signatures. Failed to verify bitcoin_signature. UnsignedChannelAnnouncement used for verification is {:?}. their_bitcoin_key is ({:?})",
4555                                 &announcement, self.counterparty_funding_pubkey())));
4556                 }
4557
4558                 self.announcement_sigs = Some((msg.node_signature, msg.bitcoin_signature));
4559
4560                 self.sign_channel_announcement(our_node_secret, our_node_id, msghash, announcement, our_bitcoin_sig)
4561         }
4562
4563         /// Gets a signed channel_announcement for this channel, if we previously received an
4564         /// announcement_signatures from our counterparty.
4565         pub fn get_signed_channel_announcement(&self, our_node_secret: &SecretKey, our_node_id: PublicKey, chain_hash: BlockHash) -> Option<msgs::ChannelAnnouncement> {
4566                 let (announcement, our_bitcoin_sig) = match self.get_channel_announcement(our_node_id.clone(), chain_hash) {
4567                         Ok(res) => res,
4568                         Err(_) => return None,
4569                 };
4570                 let msghash = hash_to_message!(&Sha256d::hash(&announcement.encode()[..])[..]);
4571                 match self.sign_channel_announcement(our_node_secret, our_node_id, msghash, announcement, our_bitcoin_sig) {
4572                         Ok(res) => Some(res),
4573                         Err(_) => None,
4574                 }
4575         }
4576
4577         /// May panic if called on a channel that wasn't immediately-previously
4578         /// self.remove_uncommitted_htlcs_and_mark_paused()'d
4579         pub fn get_channel_reestablish<L: Deref>(&self, logger: &L) -> msgs::ChannelReestablish where L::Target: Logger {
4580                 assert_eq!(self.channel_state & ChannelState::PeerDisconnected as u32, ChannelState::PeerDisconnected as u32);
4581                 assert_ne!(self.cur_counterparty_commitment_transaction_number, INITIAL_COMMITMENT_NUMBER);
4582                 // Prior to static_remotekey, my_current_per_commitment_point was critical to claiming
4583                 // current to_remote balances. However, it no longer has any use, and thus is now simply
4584                 // set to a dummy (but valid, as required by the spec) public key.
4585                 // fuzztarget mode marks a subset of pubkeys as invalid so that we can hit "invalid pubkey"
4586                 // branches, but we unwrap it below, so we arbitrarily select a dummy pubkey which is both
4587                 // valid, and valid in fuzztarget mode's arbitrary validity criteria:
4588                 let mut pk = [2; 33]; pk[1] = 0xff;
4589                 let dummy_pubkey = PublicKey::from_slice(&pk).unwrap();
4590                 let data_loss_protect = if self.cur_counterparty_commitment_transaction_number + 1 < INITIAL_COMMITMENT_NUMBER {
4591                         let remote_last_secret = self.commitment_secrets.get_secret(self.cur_counterparty_commitment_transaction_number + 2).unwrap();
4592                         log_trace!(logger, "Enough info to generate a Data Loss Protect with per_commitment_secret {} for channel {}", log_bytes!(remote_last_secret), log_bytes!(self.channel_id()));
4593                         OptionalField::Present(DataLossProtect {
4594                                 your_last_per_commitment_secret: remote_last_secret,
4595                                 my_current_per_commitment_point: dummy_pubkey
4596                         })
4597                 } else {
4598                         log_info!(logger, "Sending a data_loss_protect with no previous remote per_commitment_secret for channel {}", log_bytes!(self.channel_id()));
4599                         OptionalField::Present(DataLossProtect {
4600                                 your_last_per_commitment_secret: [0;32],
4601                                 my_current_per_commitment_point: dummy_pubkey,
4602                         })
4603                 };
4604                 msgs::ChannelReestablish {
4605                         channel_id: self.channel_id(),
4606                         // The protocol has two different commitment number concepts - the "commitment
4607                         // transaction number", which starts from 0 and counts up, and the "revocation key
4608                         // index" which starts at INITIAL_COMMITMENT_NUMBER and counts down. We track
4609                         // commitment transaction numbers by the index which will be used to reveal the
4610                         // revocation key for that commitment transaction, which means we have to convert them
4611                         // to protocol-level commitment numbers here...
4612
4613                         // next_local_commitment_number is the next commitment_signed number we expect to
4614                         // receive (indicating if they need to resend one that we missed).
4615                         next_local_commitment_number: INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number,
4616                         // We have to set next_remote_commitment_number to the next revoke_and_ack we expect to
4617                         // receive, however we track it by the next commitment number for a remote transaction
4618                         // (which is one further, as they always revoke previous commitment transaction, not
4619                         // the one we send) so we have to decrement by 1. Note that if
4620                         // cur_counterparty_commitment_transaction_number is INITIAL_COMMITMENT_NUMBER we will have
4621                         // dropped this channel on disconnect as it hasn't yet reached FundingSent so we can't
4622                         // overflow here.
4623                         next_remote_commitment_number: INITIAL_COMMITMENT_NUMBER - self.cur_counterparty_commitment_transaction_number - 1,
4624                         data_loss_protect,
4625                 }
4626         }
4627
4628
4629         // Send stuff to our remote peers:
4630
4631         /// Adds a pending outbound HTLC to this channel, note that you probably want
4632         /// send_htlc_and_commit instead cause you'll want both messages at once.
4633         ///
4634         /// This returns an optional UpdateAddHTLC as we may be in a state where we cannot add HTLCs on
4635         /// the wire:
4636         /// * In cases where we're waiting on the remote peer to send us a revoke_and_ack, we
4637         ///   wouldn't be able to determine what they actually ACK'ed if we have two sets of updates
4638         ///   awaiting ACK.
4639         /// * In cases where we're marked MonitorUpdateFailed, we cannot commit to a new state as we
4640         ///   may not yet have sent the previous commitment update messages and will need to regenerate
4641         ///   them.
4642         ///
4643         /// You MUST call send_commitment prior to calling any other methods on this Channel!
4644         ///
4645         /// If an Err is returned, it's a ChannelError::Ignore!
4646         pub fn send_htlc<L: Deref>(&mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket, logger: &L) -> Result<Option<msgs::UpdateAddHTLC>, ChannelError> where L::Target: Logger {
4647                 if (self.channel_state & (ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK)) != (ChannelState::ChannelFunded as u32) {
4648                         return Err(ChannelError::Ignore("Cannot send HTLC until channel is fully established and we haven't started shutting down".to_owned()));
4649                 }
4650                 let channel_total_msat = self.channel_value_satoshis * 1000;
4651                 if amount_msat > channel_total_msat {
4652                         return Err(ChannelError::Ignore(format!("Cannot send amount {}, because it is more than the total value of the channel {}", amount_msat, channel_total_msat)));
4653                 }
4654
4655                 if amount_msat == 0 {
4656                         return Err(ChannelError::Ignore("Cannot send 0-msat HTLC".to_owned()));
4657                 }
4658
4659                 if amount_msat < self.counterparty_htlc_minimum_msat {
4660                         return Err(ChannelError::Ignore(format!("Cannot send less than their minimum HTLC value ({})", self.counterparty_htlc_minimum_msat)));
4661                 }
4662
4663                 if (self.channel_state & (ChannelState::PeerDisconnected as u32)) != 0 {
4664                         // Note that this should never really happen, if we're !is_live() on receipt of an
4665                         // incoming HTLC for relay will result in us rejecting the HTLC and we won't allow
4666                         // the user to send directly into a !is_live() channel. However, if we
4667                         // disconnected during the time the previous hop was doing the commitment dance we may
4668                         // end up getting here after the forwarding delay. In any case, returning an
4669                         // IgnoreError will get ChannelManager to do the right thing and fail backwards now.
4670                         return Err(ChannelError::Ignore("Cannot send an HTLC while disconnected from channel counterparty".to_owned()));
4671                 }
4672
4673                 let inbound_stats = self.get_inbound_pending_htlc_stats(None);
4674                 let outbound_stats = self.get_outbound_pending_htlc_stats(None);
4675                 if outbound_stats.pending_htlcs + 1 > self.counterparty_max_accepted_htlcs as u32 {
4676                         return Err(ChannelError::Ignore(format!("Cannot push more than their max accepted HTLCs ({})", self.counterparty_max_accepted_htlcs)));
4677                 }
4678                 // Check their_max_htlc_value_in_flight_msat
4679                 if outbound_stats.pending_htlcs_value_msat + amount_msat > self.counterparty_max_htlc_value_in_flight_msat {
4680                         return Err(ChannelError::Ignore(format!("Cannot send value that would put us over the max HTLC value in flight our peer will accept ({})", self.counterparty_max_htlc_value_in_flight_msat)));
4681                 }
4682
4683                 let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number)?;
4684                 if !self.is_outbound() {
4685                         // Check that we won't violate the remote channel reserve by adding this HTLC.
4686                         let counterparty_balance_msat = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, true, logger).5;
4687                         let htlc_candidate = HTLCCandidate::new(amount_msat, HTLCInitiator::LocalOffered);
4688                         let counterparty_commit_tx_fee_msat = self.next_remote_commit_tx_fee_msat(htlc_candidate, None);
4689                         let holder_selected_chan_reserve_msat = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis) * 1000;
4690                         if counterparty_balance_msat < counterparty_commit_tx_fee_msat + holder_selected_chan_reserve_msat {
4691                                 return Err(ChannelError::Ignore("Cannot send value that would put counterparty balance under holder-announced channel reserve value".to_owned()));
4692                         }
4693                 }
4694
4695                 let exposure_dust_limit_success_sats = (self.get_dust_buffer_feerate(None) as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
4696                 if amount_msat / 1000 < exposure_dust_limit_success_sats {
4697                         let on_counterparty_dust_htlc_exposure_msat = inbound_stats.on_counterparty_tx_dust_exposure_msat + outbound_stats.on_counterparty_tx_dust_exposure_msat + amount_msat;
4698                         if on_counterparty_dust_htlc_exposure_msat > self.get_max_dust_htlc_exposure_msat() {
4699                                 return Err(ChannelError::Ignore(format!("Cannot send value that would put our exposure to dust HTLCs at {} over the limit {} on counterparty commitment tx",
4700                                         on_counterparty_dust_htlc_exposure_msat, self.get_max_dust_htlc_exposure_msat())));
4701                         }
4702                 }
4703
4704                 let exposure_dust_limit_timeout_sats = (self.get_dust_buffer_feerate(None) as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
4705                 if amount_msat / 1000 <  exposure_dust_limit_timeout_sats {
4706                         let on_holder_dust_htlc_exposure_msat = inbound_stats.on_holder_tx_dust_exposure_msat + outbound_stats.on_holder_tx_dust_exposure_msat + amount_msat;
4707                         if on_holder_dust_htlc_exposure_msat > self.get_max_dust_htlc_exposure_msat() {
4708                                 return Err(ChannelError::Ignore(format!("Cannot send value that would put our exposure to dust HTLCs at {} over the limit {} on holder commitment tx",
4709                                         on_holder_dust_htlc_exposure_msat, self.get_max_dust_htlc_exposure_msat())));
4710                         }
4711                 }
4712
4713                 let holder_balance_msat = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, true, logger).4 as u64 - outbound_stats.holding_cell_msat;
4714                 if holder_balance_msat < amount_msat {
4715                         return Err(ChannelError::Ignore(format!("Cannot send value that would overdraw remaining funds. Amount: {}, pending value to self {}", amount_msat, holder_balance_msat)));
4716                 }
4717
4718                 // `2 *` and extra HTLC are for the fee spike buffer.
4719                 let commit_tx_fee_msat = if self.is_outbound() {
4720                         let htlc_candidate = HTLCCandidate::new(amount_msat, HTLCInitiator::LocalOffered);
4721                         FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE * self.next_local_commit_tx_fee_msat(htlc_candidate, Some(()))
4722                 } else { 0 };
4723                 if holder_balance_msat - amount_msat < commit_tx_fee_msat {
4724                         return Err(ChannelError::Ignore(format!("Cannot send value that would not leave enough to pay for fees. Pending value to self: {}. local_commit_tx_fee {}", holder_balance_msat, commit_tx_fee_msat)));
4725                 }
4726
4727                 // Check self.counterparty_selected_channel_reserve_satoshis (the amount we must keep as
4728                 // reserve for the remote to have something to claim if we misbehave)
4729                 let chan_reserve_msat = self.counterparty_selected_channel_reserve_satoshis.unwrap() * 1000;
4730                 if holder_balance_msat - amount_msat - commit_tx_fee_msat < chan_reserve_msat {
4731                         return Err(ChannelError::Ignore(format!("Cannot send value that would put our balance under counterparty-announced channel reserve value ({})", chan_reserve_msat)));
4732                 }
4733
4734                 // Now update local state:
4735                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
4736                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::AddHTLC {
4737                                 amount_msat,
4738                                 payment_hash,
4739                                 cltv_expiry,
4740                                 source,
4741                                 onion_routing_packet,
4742                         });
4743                         return Ok(None);
4744                 }
4745
4746                 self.pending_outbound_htlcs.push(OutboundHTLCOutput {
4747                         htlc_id: self.next_holder_htlc_id,
4748                         amount_msat,
4749                         payment_hash: payment_hash.clone(),
4750                         cltv_expiry,
4751                         state: OutboundHTLCState::LocalAnnounced(Box::new(onion_routing_packet.clone())),
4752                         source,
4753                 });
4754
4755                 let res = msgs::UpdateAddHTLC {
4756                         channel_id: self.channel_id,
4757                         htlc_id: self.next_holder_htlc_id,
4758                         amount_msat,
4759                         payment_hash,
4760                         cltv_expiry,
4761                         onion_routing_packet,
4762                 };
4763                 self.next_holder_htlc_id += 1;
4764
4765                 Ok(Some(res))
4766         }
4767
4768         /// Creates a signed commitment transaction to send to the remote peer.
4769         /// Always returns a ChannelError::Close if an immediately-preceding (read: the
4770         /// last call to this Channel) send_htlc returned Ok(Some(_)) and there is an Err.
4771         /// May panic if called except immediately after a successful, Ok(Some(_))-returning send_htlc.
4772         pub fn send_commitment<L: Deref>(&mut self, logger: &L) -> Result<(msgs::CommitmentSigned, ChannelMonitorUpdate), ChannelError> where L::Target: Logger {
4773                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
4774                         panic!("Cannot create commitment tx until channel is fully established");
4775                 }
4776                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
4777                         panic!("Cannot create commitment tx until remote revokes their previous commitment");
4778                 }
4779                 if (self.channel_state & (ChannelState::PeerDisconnected as u32)) == (ChannelState::PeerDisconnected as u32) {
4780                         panic!("Cannot create commitment tx while disconnected, as send_htlc will have returned an Err so a send_commitment precondition has been violated");
4781                 }
4782                 if (self.channel_state & (ChannelState::MonitorUpdateFailed as u32)) == (ChannelState::MonitorUpdateFailed as u32) {
4783                         panic!("Cannot create commitment tx while awaiting monitor update unfreeze, as send_htlc will have returned an Err so a send_commitment precondition has been violated");
4784                 }
4785                 let mut have_updates = self.is_outbound() && self.pending_update_fee.is_some();
4786                 for htlc in self.pending_outbound_htlcs.iter() {
4787                         if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
4788                                 have_updates = true;
4789                         }
4790                         if have_updates { break; }
4791                 }
4792                 for htlc in self.pending_inbound_htlcs.iter() {
4793                         if let InboundHTLCState::LocalRemoved(_) = htlc.state {
4794                                 have_updates = true;
4795                         }
4796                         if have_updates { break; }
4797                 }
4798                 if !have_updates {
4799                         panic!("Cannot create commitment tx until we have some updates to send");
4800                 }
4801                 self.send_commitment_no_status_check(logger)
4802         }
4803         /// Only fails in case of bad keys
4804         fn send_commitment_no_status_check<L: Deref>(&mut self, logger: &L) -> Result<(msgs::CommitmentSigned, ChannelMonitorUpdate), ChannelError> where L::Target: Logger {
4805                 log_trace!(logger, "Updating HTLC state for a newly-sent commitment_signed...");
4806                 // We can upgrade the status of some HTLCs that are waiting on a commitment, even if we
4807                 // fail to generate this, we still are at least at a position where upgrading their status
4808                 // is acceptable.
4809                 for htlc in self.pending_inbound_htlcs.iter_mut() {
4810                         let new_state = if let &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(ref forward_info) = &htlc.state {
4811                                 Some(InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info.clone()))
4812                         } else { None };
4813                         if let Some(state) = new_state {
4814                                 log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce {} to AwaitingAnnouncedRemoteRevoke", log_bytes!(htlc.payment_hash.0));
4815                                 htlc.state = state;
4816                         }
4817                 }
4818                 for htlc in self.pending_outbound_htlcs.iter_mut() {
4819                         if let Some(fail_reason) = if let &mut OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref mut fail_reason) = &mut htlc.state {
4820                                 Some(fail_reason.take())
4821                         } else { None } {
4822                                 log_trace!(logger, " ...promoting outbound AwaitingRemoteRevokeToRemove {} to AwaitingRemovedRemoteRevoke", log_bytes!(htlc.payment_hash.0));
4823                                 htlc.state = OutboundHTLCState::AwaitingRemovedRemoteRevoke(fail_reason);
4824                         }
4825                 }
4826                 if let Some((feerate, update_state)) = self.pending_update_fee {
4827                         if update_state == FeeUpdateState::AwaitingRemoteRevokeToAnnounce {
4828                                 debug_assert!(!self.is_outbound());
4829                                 log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce fee update {} to Committed", feerate);
4830                                 self.feerate_per_kw = feerate;
4831                                 self.pending_update_fee = None;
4832                         }
4833                 }
4834                 self.resend_order = RAACommitmentOrder::RevokeAndACKFirst;
4835
4836                 let (res, counterparty_commitment_txid, htlcs) = match self.send_commitment_no_state_update(logger) {
4837                         Ok((res, (counterparty_commitment_tx, mut htlcs))) => {
4838                                 // Update state now that we've passed all the can-fail calls...
4839                                 let htlcs_no_ref: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)> =
4840                                         htlcs.drain(..).map(|(htlc, htlc_source)| (htlc, htlc_source.map(|source_ref| Box::new(source_ref.clone())))).collect();
4841                                 (res, counterparty_commitment_tx, htlcs_no_ref)
4842                         },
4843                         Err(e) => return Err(e),
4844                 };
4845
4846                 self.latest_monitor_update_id += 1;
4847                 let monitor_update = ChannelMonitorUpdate {
4848                         update_id: self.latest_monitor_update_id,
4849                         updates: vec![ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo {
4850                                 commitment_txid: counterparty_commitment_txid,
4851                                 htlc_outputs: htlcs.clone(),
4852                                 commitment_number: self.cur_counterparty_commitment_transaction_number,
4853                                 their_revocation_point: self.counterparty_cur_commitment_point.unwrap()
4854                         }]
4855                 };
4856                 self.channel_state |= ChannelState::AwaitingRemoteRevoke as u32;
4857                 Ok((res, monitor_update))
4858         }
4859
4860         /// Only fails in case of bad keys. Used for channel_reestablish commitment_signed generation
4861         /// when we shouldn't change HTLC/channel state.
4862         fn send_commitment_no_state_update<L: Deref>(&self, logger: &L) -> Result<(msgs::CommitmentSigned, (Txid, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>)), ChannelError> where L::Target: Logger {
4863                 let counterparty_keys = self.build_remote_transaction_keys()?;
4864                 let counterparty_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, true, logger);
4865                 let feerate_per_kw = counterparty_commitment_tx.1;
4866                 let counterparty_commitment_txid = counterparty_commitment_tx.0.trust().txid();
4867                 let (signature, htlc_signatures);
4868
4869                 #[cfg(any(test, feature = "fuzztarget"))]
4870                 {
4871                         if !self.is_outbound() {
4872                                 let projected_commit_tx_info = self.next_remote_commitment_tx_fee_info_cached.lock().unwrap().take();
4873                                 *self.next_local_commitment_tx_fee_info_cached.lock().unwrap() = None;
4874                                 if let Some(info) = projected_commit_tx_info {
4875                                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len();
4876                                         if info.total_pending_htlcs == total_pending_htlcs
4877                                                 && info.next_holder_htlc_id == self.next_holder_htlc_id
4878                                                 && info.next_counterparty_htlc_id == self.next_counterparty_htlc_id
4879                                                 && info.feerate == self.feerate_per_kw {
4880                                                         let actual_fee = self.commit_tx_fee_msat(counterparty_commitment_tx.2);
4881                                                         assert_eq!(actual_fee, info.fee);
4882                                                 }
4883                                 }
4884                         }
4885                 }
4886
4887                 {
4888                         let mut htlcs = Vec::with_capacity(counterparty_commitment_tx.3.len());
4889                         for &(ref htlc, _) in counterparty_commitment_tx.3.iter() {
4890                                 htlcs.push(htlc);
4891                         }
4892
4893                         let res = self.holder_signer.sign_counterparty_commitment(&counterparty_commitment_tx.0, &self.secp_ctx)
4894                                 .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?;
4895                         signature = res.0;
4896                         htlc_signatures = res.1;
4897
4898                         log_trace!(logger, "Signed remote commitment tx {} (txid {}) with redeemscript {} -> {} in channel {}",
4899                                 encode::serialize_hex(&counterparty_commitment_tx.0.trust().built_transaction().transaction),
4900                                 &counterparty_commitment_txid, encode::serialize_hex(&self.get_funding_redeemscript()),
4901                                 log_bytes!(signature.serialize_compact()[..]), log_bytes!(self.channel_id()));
4902
4903                         for (ref htlc_sig, ref htlc) in htlc_signatures.iter().zip(htlcs) {
4904                                 log_trace!(logger, "Signed remote HTLC tx {} with redeemscript {} with pubkey {} -> {} in channel {}",
4905                                         encode::serialize_hex(&chan_utils::build_htlc_transaction(&counterparty_commitment_txid, feerate_per_kw, self.get_holder_selected_contest_delay(), htlc, &counterparty_keys.broadcaster_delayed_payment_key, &counterparty_keys.revocation_key)),
4906                                         encode::serialize_hex(&chan_utils::get_htlc_redeemscript(&htlc, &counterparty_keys)),
4907                                         log_bytes!(counterparty_keys.broadcaster_htlc_key.serialize()),
4908                                         log_bytes!(htlc_sig.serialize_compact()[..]), log_bytes!(self.channel_id()));
4909                         }
4910                 }
4911
4912                 Ok((msgs::CommitmentSigned {
4913                         channel_id: self.channel_id,
4914                         signature,
4915                         htlc_signatures,
4916                 }, (counterparty_commitment_txid, counterparty_commitment_tx.3)))
4917         }
4918
4919         /// Adds a pending outbound HTLC to this channel, and creates a signed commitment transaction
4920         /// to send to the remote peer in one go.
4921         /// Shorthand for calling send_htlc() followed by send_commitment(), see docs on those for
4922         /// more info.
4923         pub fn send_htlc_and_commit<L: Deref>(&mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket, logger: &L) -> Result<Option<(msgs::UpdateAddHTLC, msgs::CommitmentSigned, ChannelMonitorUpdate)>, ChannelError> where L::Target: Logger {
4924                 match self.send_htlc(amount_msat, payment_hash, cltv_expiry, source, onion_routing_packet, logger)? {
4925                         Some(update_add_htlc) => {
4926                                 let (commitment_signed, monitor_update) = self.send_commitment_no_status_check(logger)?;
4927                                 Ok(Some((update_add_htlc, commitment_signed, monitor_update)))
4928                         },
4929                         None => Ok(None)
4930                 }
4931         }
4932
4933         /// Get forwarding information for the counterparty.
4934         pub fn counterparty_forwarding_info(&self) -> Option<CounterpartyForwardingInfo> {
4935                 self.counterparty_forwarding_info.clone()
4936         }
4937
4938         pub fn channel_update(&mut self, msg: &msgs::ChannelUpdate) -> Result<(), ChannelError> {
4939                 if msg.contents.htlc_minimum_msat >= self.channel_value_satoshis * 1000 {
4940                         return Err(ChannelError::Close("Minimum htlc value is greater than channel value".to_string()));
4941                 }
4942                 self.counterparty_forwarding_info = Some(CounterpartyForwardingInfo {
4943                         fee_base_msat: msg.contents.fee_base_msat,
4944                         fee_proportional_millionths: msg.contents.fee_proportional_millionths,
4945                         cltv_expiry_delta: msg.contents.cltv_expiry_delta
4946                 });
4947
4948                 Ok(())
4949         }
4950
4951         /// Begins the shutdown process, getting a message for the remote peer and returning all
4952         /// holding cell HTLCs for payment failure.
4953         pub fn get_shutdown<K: Deref>(&mut self, keys_provider: &K, their_features: &InitFeatures, target_feerate_sats_per_kw: Option<u32>)
4954         -> Result<(msgs::Shutdown, Option<ChannelMonitorUpdate>, Vec<(HTLCSource, PaymentHash)>), APIError>
4955         where K::Target: KeysInterface<Signer = Signer> {
4956                 for htlc in self.pending_outbound_htlcs.iter() {
4957                         if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
4958                                 return Err(APIError::APIMisuseError{err: "Cannot begin shutdown with pending HTLCs. Process pending events first".to_owned()});
4959                         }
4960                 }
4961                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != 0 {
4962                         if (self.channel_state & ChannelState::LocalShutdownSent as u32) == ChannelState::LocalShutdownSent as u32 {
4963                                 return Err(APIError::APIMisuseError{err: "Shutdown already in progress".to_owned()});
4964                         }
4965                         else if (self.channel_state & ChannelState::RemoteShutdownSent as u32) == ChannelState::RemoteShutdownSent as u32 {
4966                                 return Err(APIError::ChannelUnavailable{err: "Shutdown already in progress by remote".to_owned()});
4967                         }
4968                 }
4969                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
4970                 if self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32) != 0 {
4971                         return Err(APIError::ChannelUnavailable{err: "Cannot begin shutdown while peer is disconnected or we're waiting on a monitor update, maybe force-close instead?".to_owned()});
4972                 }
4973
4974                 let update_shutdown_script = match self.shutdown_scriptpubkey {
4975                         Some(_) => false,
4976                         None => {
4977                                 let shutdown_scriptpubkey = keys_provider.get_shutdown_scriptpubkey();
4978                                 if !shutdown_scriptpubkey.is_compatible(their_features) {
4979                                         return Err(APIError::IncompatibleShutdownScript { script: shutdown_scriptpubkey.clone() });
4980                                 }
4981                                 self.shutdown_scriptpubkey = Some(shutdown_scriptpubkey);
4982                                 true
4983                         },
4984                 };
4985
4986                 // From here on out, we may not fail!
4987                 self.target_closing_feerate_sats_per_kw = target_feerate_sats_per_kw;
4988                 if self.channel_state < ChannelState::FundingSent as u32 {
4989                         self.channel_state = ChannelState::ShutdownComplete as u32;
4990                 } else {
4991                         self.channel_state |= ChannelState::LocalShutdownSent as u32;
4992                 }
4993                 self.update_time_counter += 1;
4994
4995                 let monitor_update = if update_shutdown_script {
4996                         self.latest_monitor_update_id += 1;
4997                         Some(ChannelMonitorUpdate {
4998                                 update_id: self.latest_monitor_update_id,
4999                                 updates: vec![ChannelMonitorUpdateStep::ShutdownScript {
5000                                         scriptpubkey: self.get_closing_scriptpubkey(),
5001                                 }],
5002                         })
5003                 } else { None };
5004                 let shutdown = msgs::Shutdown {
5005                         channel_id: self.channel_id,
5006                         scriptpubkey: self.get_closing_scriptpubkey(),
5007                 };
5008
5009                 // Go ahead and drop holding cell updates as we'd rather fail payments than wait to send
5010                 // our shutdown until we've committed all of the pending changes.
5011                 self.holding_cell_update_fee = None;
5012                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
5013                 self.holding_cell_htlc_updates.retain(|htlc_update| {
5014                         match htlc_update {
5015                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
5016                                         dropped_outbound_htlcs.push((source.clone(), payment_hash.clone()));
5017                                         false
5018                                 },
5019                                 _ => true
5020                         }
5021                 });
5022
5023                 Ok((shutdown, monitor_update, dropped_outbound_htlcs))
5024         }
5025
5026         /// Gets the latest commitment transaction and any dependent transactions for relay (forcing
5027         /// shutdown of this channel - no more calls into this Channel may be made afterwards except
5028         /// those explicitly stated to be allowed after shutdown completes, eg some simple getters).
5029         /// Also returns the list of payment_hashes for channels which we can safely fail backwards
5030         /// immediately (others we will have to allow to time out).
5031         pub fn force_shutdown(&mut self, should_broadcast: bool) -> (Option<(OutPoint, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>) {
5032                 // Note that we MUST only generate a monitor update that indicates force-closure - we're
5033                 // called during initialization prior to the chain_monitor in the encompassing ChannelManager
5034                 // being fully configured in some cases. Thus, its likely any monitor events we generate will
5035                 // be delayed in being processed! See the docs for `ChannelManagerReadArgs` for more.
5036                 assert!(self.channel_state != ChannelState::ShutdownComplete as u32);
5037
5038                 // We go ahead and "free" any holding cell HTLCs or HTLCs we haven't yet committed to and
5039                 // return them to fail the payment.
5040                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
5041                 for htlc_update in self.holding_cell_htlc_updates.drain(..) {
5042                         match htlc_update {
5043                                 HTLCUpdateAwaitingACK::AddHTLC { source, payment_hash, .. } => {
5044                                         dropped_outbound_htlcs.push((source, payment_hash));
5045                                 },
5046                                 _ => {}
5047                         }
5048                 }
5049                 let monitor_update = if let Some(funding_txo) = self.get_funding_txo() {
5050                         // If we haven't yet exchanged funding signatures (ie channel_state < FundingSent),
5051                         // returning a channel monitor update here would imply a channel monitor update before
5052                         // we even registered the channel monitor to begin with, which is invalid.
5053                         // Thus, if we aren't actually at a point where we could conceivably broadcast the
5054                         // funding transaction, don't return a funding txo (which prevents providing the
5055                         // monitor update to the user, even if we return one).
5056                         // See test_duplicate_chan_id and test_pre_lockin_no_chan_closed_update for more.
5057                         if self.channel_state & (ChannelState::FundingSent as u32 | ChannelState::ChannelFunded as u32 | ChannelState::ShutdownComplete as u32) != 0 {
5058                                 self.latest_monitor_update_id += 1;
5059                                 Some((funding_txo, ChannelMonitorUpdate {
5060                                         update_id: self.latest_monitor_update_id,
5061                                         updates: vec![ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast }],
5062                                 }))
5063                         } else { None }
5064                 } else { None };
5065
5066                 self.channel_state = ChannelState::ShutdownComplete as u32;
5067                 self.update_time_counter += 1;
5068                 (monitor_update, dropped_outbound_htlcs)
5069         }
5070 }
5071
5072 const SERIALIZATION_VERSION: u8 = 2;
5073 const MIN_SERIALIZATION_VERSION: u8 = 1;
5074
5075 impl_writeable_tlv_based_enum!(InboundHTLCRemovalReason,;
5076         (0, FailRelay),
5077         (1, FailMalformed),
5078         (2, Fulfill),
5079 );
5080
5081 impl Writeable for ChannelUpdateStatus {
5082         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
5083                 // We only care about writing out the current state as it was announced, ie only either
5084                 // Enabled or Disabled. In the case of DisabledStaged, we most recently announced the
5085                 // channel as enabled, so we write 0. For EnabledStaged, we similarly write a 1.
5086                 match self {
5087                         ChannelUpdateStatus::Enabled => 0u8.write(writer)?,
5088                         ChannelUpdateStatus::DisabledStaged => 0u8.write(writer)?,
5089                         ChannelUpdateStatus::EnabledStaged => 1u8.write(writer)?,
5090                         ChannelUpdateStatus::Disabled => 1u8.write(writer)?,
5091                 }
5092                 Ok(())
5093         }
5094 }
5095
5096 impl Readable for ChannelUpdateStatus {
5097         fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
5098                 Ok(match <u8 as Readable>::read(reader)? {
5099                         0 => ChannelUpdateStatus::Enabled,
5100                         1 => ChannelUpdateStatus::Disabled,
5101                         _ => return Err(DecodeError::InvalidValue),
5102                 })
5103         }
5104 }
5105
5106 impl<Signer: Sign> Writeable for Channel<Signer> {
5107         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
5108                 // Note that we write out as if remove_uncommitted_htlcs_and_mark_paused had just been
5109                 // called.
5110
5111                 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
5112
5113                 self.user_id.write(writer)?;
5114
5115                 // Write out the old serialization for the config object. This is read by version-1
5116                 // deserializers, but we will read the version in the TLV at the end instead.
5117                 self.config.forwarding_fee_proportional_millionths.write(writer)?;
5118                 self.config.cltv_expiry_delta.write(writer)?;
5119                 self.config.announced_channel.write(writer)?;
5120                 self.config.commit_upfront_shutdown_pubkey.write(writer)?;
5121
5122                 self.channel_id.write(writer)?;
5123                 (self.channel_state | ChannelState::PeerDisconnected as u32).write(writer)?;
5124                 self.channel_value_satoshis.write(writer)?;
5125
5126                 self.latest_monitor_update_id.write(writer)?;
5127
5128                 let mut key_data = VecWriter(Vec::new());
5129                 self.holder_signer.write(&mut key_data)?;
5130                 assert!(key_data.0.len() < core::usize::MAX);
5131                 assert!(key_data.0.len() < core::u32::MAX as usize);
5132                 (key_data.0.len() as u32).write(writer)?;
5133                 writer.write_all(&key_data.0[..])?;
5134
5135                 // Write out the old serialization for shutdown_pubkey for backwards compatibility, if
5136                 // deserialized from that format.
5137                 match self.shutdown_scriptpubkey.as_ref().and_then(|script| script.as_legacy_pubkey()) {
5138                         Some(shutdown_pubkey) => shutdown_pubkey.write(writer)?,
5139                         None => [0u8; PUBLIC_KEY_SIZE].write(writer)?,
5140                 }
5141                 self.destination_script.write(writer)?;
5142
5143                 self.cur_holder_commitment_transaction_number.write(writer)?;
5144                 self.cur_counterparty_commitment_transaction_number.write(writer)?;
5145                 self.value_to_self_msat.write(writer)?;
5146
5147                 let mut dropped_inbound_htlcs = 0;
5148                 for htlc in self.pending_inbound_htlcs.iter() {
5149                         if let InboundHTLCState::RemoteAnnounced(_) = htlc.state {
5150                                 dropped_inbound_htlcs += 1;
5151                         }
5152                 }
5153                 (self.pending_inbound_htlcs.len() as u64 - dropped_inbound_htlcs).write(writer)?;
5154                 for htlc in self.pending_inbound_htlcs.iter() {
5155                         if let &InboundHTLCState::RemoteAnnounced(_) = &htlc.state {
5156                                 continue; // Drop
5157                         }
5158                         htlc.htlc_id.write(writer)?;
5159                         htlc.amount_msat.write(writer)?;
5160                         htlc.cltv_expiry.write(writer)?;
5161                         htlc.payment_hash.write(writer)?;
5162                         match &htlc.state {
5163                                 &InboundHTLCState::RemoteAnnounced(_) => unreachable!(),
5164                                 &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(ref htlc_state) => {
5165                                         1u8.write(writer)?;
5166                                         htlc_state.write(writer)?;
5167                                 },
5168                                 &InboundHTLCState::AwaitingAnnouncedRemoteRevoke(ref htlc_state) => {
5169                                         2u8.write(writer)?;
5170                                         htlc_state.write(writer)?;
5171                                 },
5172                                 &InboundHTLCState::Committed => {
5173                                         3u8.write(writer)?;
5174                                 },
5175                                 &InboundHTLCState::LocalRemoved(ref removal_reason) => {
5176                                         4u8.write(writer)?;
5177                                         removal_reason.write(writer)?;
5178                                 },
5179                         }
5180                 }
5181
5182                 (self.pending_outbound_htlcs.len() as u64).write(writer)?;
5183                 for htlc in self.pending_outbound_htlcs.iter() {
5184                         htlc.htlc_id.write(writer)?;
5185                         htlc.amount_msat.write(writer)?;
5186                         htlc.cltv_expiry.write(writer)?;
5187                         htlc.payment_hash.write(writer)?;
5188                         htlc.source.write(writer)?;
5189                         match &htlc.state {
5190                                 &OutboundHTLCState::LocalAnnounced(ref onion_packet) => {
5191                                         0u8.write(writer)?;
5192                                         onion_packet.write(writer)?;
5193                                 },
5194                                 &OutboundHTLCState::Committed => {
5195                                         1u8.write(writer)?;
5196                                 },
5197                                 &OutboundHTLCState::RemoteRemoved(_) => {
5198                                         // Treat this as a Committed because we haven't received the CS - they'll
5199                                         // resend the claim/fail on reconnect as we all (hopefully) the missing CS.
5200                                         1u8.write(writer)?;
5201                                 },
5202                                 &OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref fail_reason) => {
5203                                         3u8.write(writer)?;
5204                                         fail_reason.write(writer)?;
5205                                 },
5206                                 &OutboundHTLCState::AwaitingRemovedRemoteRevoke(ref fail_reason) => {
5207                                         4u8.write(writer)?;
5208                                         fail_reason.write(writer)?;
5209                                 },
5210                         }
5211                 }
5212
5213                 (self.holding_cell_htlc_updates.len() as u64).write(writer)?;
5214                 for update in self.holding_cell_htlc_updates.iter() {
5215                         match update {
5216                                 &HTLCUpdateAwaitingACK::AddHTLC { ref amount_msat, ref cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet } => {
5217                                         0u8.write(writer)?;
5218                                         amount_msat.write(writer)?;
5219                                         cltv_expiry.write(writer)?;
5220                                         payment_hash.write(writer)?;
5221                                         source.write(writer)?;
5222                                         onion_routing_packet.write(writer)?;
5223                                 },
5224                                 &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, ref htlc_id } => {
5225                                         1u8.write(writer)?;
5226                                         payment_preimage.write(writer)?;
5227                                         htlc_id.write(writer)?;
5228                                 },
5229                                 &HTLCUpdateAwaitingACK::FailHTLC { ref htlc_id, ref err_packet } => {
5230                                         2u8.write(writer)?;
5231                                         htlc_id.write(writer)?;
5232                                         err_packet.write(writer)?;
5233                                 }
5234                         }
5235                 }
5236
5237                 match self.resend_order {
5238                         RAACommitmentOrder::CommitmentFirst => 0u8.write(writer)?,
5239                         RAACommitmentOrder::RevokeAndACKFirst => 1u8.write(writer)?,
5240                 }
5241
5242                 self.monitor_pending_funding_locked.write(writer)?;
5243                 self.monitor_pending_revoke_and_ack.write(writer)?;
5244                 self.monitor_pending_commitment_signed.write(writer)?;
5245
5246                 (self.monitor_pending_forwards.len() as u64).write(writer)?;
5247                 for &(ref pending_forward, ref htlc_id) in self.monitor_pending_forwards.iter() {
5248                         pending_forward.write(writer)?;
5249                         htlc_id.write(writer)?;
5250                 }
5251
5252                 (self.monitor_pending_failures.len() as u64).write(writer)?;
5253                 for &(ref htlc_source, ref payment_hash, ref fail_reason) in self.monitor_pending_failures.iter() {
5254                         htlc_source.write(writer)?;
5255                         payment_hash.write(writer)?;
5256                         fail_reason.write(writer)?;
5257                 }
5258
5259                 if self.is_outbound() {
5260                         self.pending_update_fee.map(|(a, _)| a).write(writer)?;
5261                 } else if let Some((feerate, FeeUpdateState::AwaitingRemoteRevokeToAnnounce)) = self.pending_update_fee {
5262                         Some(feerate).write(writer)?;
5263                 } else {
5264                         // As for inbound HTLCs, if the update was only announced and never committed in a
5265                         // commitment_signed, drop it.
5266                         None::<u32>.write(writer)?;
5267                 }
5268                 self.holding_cell_update_fee.write(writer)?;
5269
5270                 self.next_holder_htlc_id.write(writer)?;
5271                 (self.next_counterparty_htlc_id - dropped_inbound_htlcs).write(writer)?;
5272                 self.update_time_counter.write(writer)?;
5273                 self.feerate_per_kw.write(writer)?;
5274
5275                 // Versions prior to 0.0.100 expected to read the fields of `last_sent_closing_fee` here,
5276                 // however we are supposed to restart shutdown fee negotiation on reconnect (and wipe
5277                 // `last_send_closing_fee` in `remove_uncommitted_htlcs_and_mark_paused`) so we should never
5278                 // consider the stale state on reload.
5279                 0u8.write(writer)?;
5280
5281                 self.funding_tx_confirmed_in.write(writer)?;
5282                 self.funding_tx_confirmation_height.write(writer)?;
5283                 self.short_channel_id.write(writer)?;
5284
5285                 self.counterparty_dust_limit_satoshis.write(writer)?;
5286                 self.holder_dust_limit_satoshis.write(writer)?;
5287                 self.counterparty_max_htlc_value_in_flight_msat.write(writer)?;
5288
5289                 // Note that this field is ignored by 0.0.99+ as the TLV Optional variant is used instead.
5290                 self.counterparty_selected_channel_reserve_satoshis.unwrap_or(0).write(writer)?;
5291
5292                 self.counterparty_htlc_minimum_msat.write(writer)?;
5293                 self.holder_htlc_minimum_msat.write(writer)?;
5294                 self.counterparty_max_accepted_htlcs.write(writer)?;
5295
5296                 // Note that this field is ignored by 0.0.99+ as the TLV Optional variant is used instead.
5297                 self.minimum_depth.unwrap_or(0).write(writer)?;
5298
5299                 match &self.counterparty_forwarding_info {
5300                         Some(info) => {
5301                                 1u8.write(writer)?;
5302                                 info.fee_base_msat.write(writer)?;
5303                                 info.fee_proportional_millionths.write(writer)?;
5304                                 info.cltv_expiry_delta.write(writer)?;
5305                         },
5306                         None => 0u8.write(writer)?
5307                 }
5308
5309                 self.channel_transaction_parameters.write(writer)?;
5310                 self.funding_transaction.write(writer)?;
5311
5312                 self.counterparty_cur_commitment_point.write(writer)?;
5313                 self.counterparty_prev_commitment_point.write(writer)?;
5314                 self.counterparty_node_id.write(writer)?;
5315
5316                 self.counterparty_shutdown_scriptpubkey.write(writer)?;
5317
5318                 self.commitment_secrets.write(writer)?;
5319
5320                 self.channel_update_status.write(writer)?;
5321
5322                 #[cfg(any(test, feature = "fuzztarget"))]
5323                 (self.historical_inbound_htlc_fulfills.len() as u64).write(writer)?;
5324                 #[cfg(any(test, feature = "fuzztarget"))]
5325                 for htlc in self.historical_inbound_htlc_fulfills.iter() {
5326                         htlc.write(writer)?;
5327                 }
5328
5329                 // If the channel type is something other than only-static-remote-key, then we need to have
5330                 // older clients fail to deserialize this channel at all. If the type is
5331                 // only-static-remote-key, we simply consider it "default" and don't write the channel type
5332                 // out at all.
5333                 let chan_type = if self.channel_type != ChannelTypeFeatures::only_static_remote_key() {
5334                         Some(&self.channel_type) } else { None };
5335
5336                 write_tlv_fields!(writer, {
5337                         (0, self.announcement_sigs, option),
5338                         // minimum_depth and counterparty_selected_channel_reserve_satoshis used to have a
5339                         // default value instead of being Option<>al. Thus, to maintain compatibility we write
5340                         // them twice, once with their original default values above, and once as an option
5341                         // here. On the read side, old versions will simply ignore the odd-type entries here,
5342                         // and new versions map the default values to None and allow the TLV entries here to
5343                         // override that.
5344                         (1, self.minimum_depth, option),
5345                         (2, chan_type, option),
5346                         (3, self.counterparty_selected_channel_reserve_satoshis, option),
5347                         (5, self.config, required),
5348                         (7, self.shutdown_scriptpubkey, option),
5349                         (9, self.target_closing_feerate_sats_per_kw, option),
5350                         (11, self.monitor_pending_finalized_fulfills, vec_type),
5351                         (13, self.channel_creation_height, required),
5352                 });
5353
5354                 Ok(())
5355         }
5356 }
5357
5358 const MAX_ALLOC_SIZE: usize = 64*1024;
5359 impl<'a, Signer: Sign, K: Deref> ReadableArgs<(&'a K, u32)> for Channel<Signer>
5360                 where K::Target: KeysInterface<Signer = Signer> {
5361         fn read<R : io::Read>(reader: &mut R, args: (&'a K, u32)) -> Result<Self, DecodeError> {
5362                 let (keys_source, serialized_height) = args;
5363                 let ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
5364
5365                 let user_id = Readable::read(reader)?;
5366
5367                 let mut config = Some(ChannelConfig::default());
5368                 if ver == 1 {
5369                         // Read the old serialization of the ChannelConfig from version 0.0.98.
5370                         config.as_mut().unwrap().forwarding_fee_proportional_millionths = Readable::read(reader)?;
5371                         config.as_mut().unwrap().cltv_expiry_delta = Readable::read(reader)?;
5372                         config.as_mut().unwrap().announced_channel = Readable::read(reader)?;
5373                         config.as_mut().unwrap().commit_upfront_shutdown_pubkey = Readable::read(reader)?;
5374                 } else {
5375                         // Read the 8 bytes of backwards-compatibility ChannelConfig data.
5376                         let mut _val: u64 = Readable::read(reader)?;
5377                 }
5378
5379                 let channel_id = Readable::read(reader)?;
5380                 let channel_state = Readable::read(reader)?;
5381                 let channel_value_satoshis = Readable::read(reader)?;
5382
5383                 let latest_monitor_update_id = Readable::read(reader)?;
5384
5385                 let keys_len: u32 = Readable::read(reader)?;
5386                 let mut keys_data = Vec::with_capacity(cmp::min(keys_len as usize, MAX_ALLOC_SIZE));
5387                 while keys_data.len() != keys_len as usize {
5388                         // Read 1KB at a time to avoid accidentally allocating 4GB on corrupted channel keys
5389                         let mut data = [0; 1024];
5390                         let read_slice = &mut data[0..cmp::min(1024, keys_len as usize - keys_data.len())];
5391                         reader.read_exact(read_slice)?;
5392                         keys_data.extend_from_slice(read_slice);
5393                 }
5394                 let holder_signer = keys_source.read_chan_signer(&keys_data)?;
5395
5396                 // Read the old serialization for shutdown_pubkey, preferring the TLV field later if set.
5397                 let mut shutdown_scriptpubkey = match <PublicKey as Readable>::read(reader) {
5398                         Ok(pubkey) => Some(ShutdownScript::new_p2wpkh_from_pubkey(pubkey)),
5399                         Err(_) => None,
5400                 };
5401                 let destination_script = Readable::read(reader)?;
5402
5403                 let cur_holder_commitment_transaction_number = Readable::read(reader)?;
5404                 let cur_counterparty_commitment_transaction_number = Readable::read(reader)?;
5405                 let value_to_self_msat = Readable::read(reader)?;
5406
5407                 let pending_inbound_htlc_count: u64 = Readable::read(reader)?;
5408                 let mut pending_inbound_htlcs = Vec::with_capacity(cmp::min(pending_inbound_htlc_count as usize, OUR_MAX_HTLCS as usize));
5409                 for _ in 0..pending_inbound_htlc_count {
5410                         pending_inbound_htlcs.push(InboundHTLCOutput {
5411                                 htlc_id: Readable::read(reader)?,
5412                                 amount_msat: Readable::read(reader)?,
5413                                 cltv_expiry: Readable::read(reader)?,
5414                                 payment_hash: Readable::read(reader)?,
5415                                 state: match <u8 as Readable>::read(reader)? {
5416                                         1 => InboundHTLCState::AwaitingRemoteRevokeToAnnounce(Readable::read(reader)?),
5417                                         2 => InboundHTLCState::AwaitingAnnouncedRemoteRevoke(Readable::read(reader)?),
5418                                         3 => InboundHTLCState::Committed,
5419                                         4 => InboundHTLCState::LocalRemoved(Readable::read(reader)?),
5420                                         _ => return Err(DecodeError::InvalidValue),
5421                                 },
5422                         });
5423                 }
5424
5425                 let pending_outbound_htlc_count: u64 = Readable::read(reader)?;
5426                 let mut pending_outbound_htlcs = Vec::with_capacity(cmp::min(pending_outbound_htlc_count as usize, OUR_MAX_HTLCS as usize));
5427                 for _ in 0..pending_outbound_htlc_count {
5428                         pending_outbound_htlcs.push(OutboundHTLCOutput {
5429                                 htlc_id: Readable::read(reader)?,
5430                                 amount_msat: Readable::read(reader)?,
5431                                 cltv_expiry: Readable::read(reader)?,
5432                                 payment_hash: Readable::read(reader)?,
5433                                 source: Readable::read(reader)?,
5434                                 state: match <u8 as Readable>::read(reader)? {
5435                                         0 => OutboundHTLCState::LocalAnnounced(Box::new(Readable::read(reader)?)),
5436                                         1 => OutboundHTLCState::Committed,
5437                                         2 => OutboundHTLCState::RemoteRemoved(Readable::read(reader)?),
5438                                         3 => OutboundHTLCState::AwaitingRemoteRevokeToRemove(Readable::read(reader)?),
5439                                         4 => OutboundHTLCState::AwaitingRemovedRemoteRevoke(Readable::read(reader)?),
5440                                         _ => return Err(DecodeError::InvalidValue),
5441                                 },
5442                         });
5443                 }
5444
5445                 let holding_cell_htlc_update_count: u64 = Readable::read(reader)?;
5446                 let mut holding_cell_htlc_updates = Vec::with_capacity(cmp::min(holding_cell_htlc_update_count as usize, OUR_MAX_HTLCS as usize*2));
5447                 for _ in 0..holding_cell_htlc_update_count {
5448                         holding_cell_htlc_updates.push(match <u8 as Readable>::read(reader)? {
5449                                 0 => HTLCUpdateAwaitingACK::AddHTLC {
5450                                         amount_msat: Readable::read(reader)?,
5451                                         cltv_expiry: Readable::read(reader)?,
5452                                         payment_hash: Readable::read(reader)?,
5453                                         source: Readable::read(reader)?,
5454                                         onion_routing_packet: Readable::read(reader)?,
5455                                 },
5456                                 1 => HTLCUpdateAwaitingACK::ClaimHTLC {
5457                                         payment_preimage: Readable::read(reader)?,
5458                                         htlc_id: Readable::read(reader)?,
5459                                 },
5460                                 2 => HTLCUpdateAwaitingACK::FailHTLC {
5461                                         htlc_id: Readable::read(reader)?,
5462                                         err_packet: Readable::read(reader)?,
5463                                 },
5464                                 _ => return Err(DecodeError::InvalidValue),
5465                         });
5466                 }
5467
5468                 let resend_order = match <u8 as Readable>::read(reader)? {
5469                         0 => RAACommitmentOrder::CommitmentFirst,
5470                         1 => RAACommitmentOrder::RevokeAndACKFirst,
5471                         _ => return Err(DecodeError::InvalidValue),
5472                 };
5473
5474                 let monitor_pending_funding_locked = Readable::read(reader)?;
5475                 let monitor_pending_revoke_and_ack = Readable::read(reader)?;
5476                 let monitor_pending_commitment_signed = Readable::read(reader)?;
5477
5478                 let monitor_pending_forwards_count: u64 = Readable::read(reader)?;
5479                 let mut monitor_pending_forwards = Vec::with_capacity(cmp::min(monitor_pending_forwards_count as usize, OUR_MAX_HTLCS as usize));
5480                 for _ in 0..monitor_pending_forwards_count {
5481                         monitor_pending_forwards.push((Readable::read(reader)?, Readable::read(reader)?));
5482                 }
5483
5484                 let monitor_pending_failures_count: u64 = Readable::read(reader)?;
5485                 let mut monitor_pending_failures = Vec::with_capacity(cmp::min(monitor_pending_failures_count as usize, OUR_MAX_HTLCS as usize));
5486                 for _ in 0..monitor_pending_failures_count {
5487                         monitor_pending_failures.push((Readable::read(reader)?, Readable::read(reader)?, Readable::read(reader)?));
5488                 }
5489
5490                 let pending_update_fee_value: Option<u32> = Readable::read(reader)?;
5491
5492                 let holding_cell_update_fee = Readable::read(reader)?;
5493
5494                 let next_holder_htlc_id = Readable::read(reader)?;
5495                 let next_counterparty_htlc_id = Readable::read(reader)?;
5496                 let update_time_counter = Readable::read(reader)?;
5497                 let feerate_per_kw = Readable::read(reader)?;
5498
5499                 // Versions prior to 0.0.100 expected to read the fields of `last_sent_closing_fee` here,
5500                 // however we are supposed to restart shutdown fee negotiation on reconnect (and wipe
5501                 // `last_send_closing_fee` in `remove_uncommitted_htlcs_and_mark_paused`) so we should never
5502                 // consider the stale state on reload.
5503                 match <u8 as Readable>::read(reader)? {
5504                         0 => {},
5505                         1 => {
5506                                 let _: u32 = Readable::read(reader)?;
5507                                 let _: u64 = Readable::read(reader)?;
5508                                 let _: Signature = Readable::read(reader)?;
5509                         },
5510                         _ => return Err(DecodeError::InvalidValue),
5511                 }
5512
5513                 let funding_tx_confirmed_in = Readable::read(reader)?;
5514                 let funding_tx_confirmation_height = Readable::read(reader)?;
5515                 let short_channel_id = Readable::read(reader)?;
5516
5517                 let counterparty_dust_limit_satoshis = Readable::read(reader)?;
5518                 let holder_dust_limit_satoshis = Readable::read(reader)?;
5519                 let counterparty_max_htlc_value_in_flight_msat = Readable::read(reader)?;
5520                 let mut counterparty_selected_channel_reserve_satoshis = None;
5521                 if ver == 1 {
5522                         // Read the old serialization from version 0.0.98.
5523                         counterparty_selected_channel_reserve_satoshis = Some(Readable::read(reader)?);
5524                 } else {
5525                         // Read the 8 bytes of backwards-compatibility data.
5526                         let _dummy: u64 = Readable::read(reader)?;
5527                 }
5528                 let counterparty_htlc_minimum_msat = Readable::read(reader)?;
5529                 let holder_htlc_minimum_msat = Readable::read(reader)?;
5530                 let counterparty_max_accepted_htlcs = Readable::read(reader)?;
5531
5532                 let mut minimum_depth = None;
5533                 if ver == 1 {
5534                         // Read the old serialization from version 0.0.98.
5535                         minimum_depth = Some(Readable::read(reader)?);
5536                 } else {
5537                         // Read the 4 bytes of backwards-compatibility data.
5538                         let _dummy: u32 = Readable::read(reader)?;
5539                 }
5540
5541                 let counterparty_forwarding_info = match <u8 as Readable>::read(reader)? {
5542                         0 => None,
5543                         1 => Some(CounterpartyForwardingInfo {
5544                                 fee_base_msat: Readable::read(reader)?,
5545                                 fee_proportional_millionths: Readable::read(reader)?,
5546                                 cltv_expiry_delta: Readable::read(reader)?,
5547                         }),
5548                         _ => return Err(DecodeError::InvalidValue),
5549                 };
5550
5551                 let channel_parameters: ChannelTransactionParameters = Readable::read(reader)?;
5552                 let funding_transaction = Readable::read(reader)?;
5553
5554                 let counterparty_cur_commitment_point = Readable::read(reader)?;
5555
5556                 let counterparty_prev_commitment_point = Readable::read(reader)?;
5557                 let counterparty_node_id = Readable::read(reader)?;
5558
5559                 let counterparty_shutdown_scriptpubkey = Readable::read(reader)?;
5560                 let commitment_secrets = Readable::read(reader)?;
5561
5562                 let channel_update_status = Readable::read(reader)?;
5563
5564                 #[cfg(any(test, feature = "fuzztarget"))]
5565                 let mut historical_inbound_htlc_fulfills = HashSet::new();
5566                 #[cfg(any(test, feature = "fuzztarget"))]
5567                 {
5568                         let htlc_fulfills_len: u64 = Readable::read(reader)?;
5569                         for _ in 0..htlc_fulfills_len {
5570                                 assert!(historical_inbound_htlc_fulfills.insert(Readable::read(reader)?));
5571                         }
5572                 }
5573
5574                 let pending_update_fee = if let Some(feerate) = pending_update_fee_value {
5575                         Some((feerate, if channel_parameters.is_outbound_from_holder {
5576                                 FeeUpdateState::Outbound
5577                         } else {
5578                                 FeeUpdateState::AwaitingRemoteRevokeToAnnounce
5579                         }))
5580                 } else {
5581                         None
5582                 };
5583
5584                 let mut announcement_sigs = None;
5585                 let mut target_closing_feerate_sats_per_kw = None;
5586                 let mut monitor_pending_finalized_fulfills = Some(Vec::new());
5587                 // Prior to supporting channel type negotiation, all of our channels were static_remotekey
5588                 // only, so we default to that if none was written.
5589                 let mut channel_type = Some(ChannelTypeFeatures::only_static_remote_key());
5590                 let mut channel_creation_height = Some(serialized_height);
5591                 read_tlv_fields!(reader, {
5592                         (0, announcement_sigs, option),
5593                         (1, minimum_depth, option),
5594                         (2, channel_type, option),
5595                         (3, counterparty_selected_channel_reserve_satoshis, option),
5596                         (5, config, option), // Note that if none is provided we will *not* overwrite the existing one.
5597                         (7, shutdown_scriptpubkey, option),
5598                         (9, target_closing_feerate_sats_per_kw, option),
5599                         (11, monitor_pending_finalized_fulfills, vec_type),
5600                         (13, channel_creation_height, option),
5601                 });
5602
5603                 let chan_features = channel_type.as_ref().unwrap();
5604                 if chan_features.supports_unknown_bits() || chan_features.requires_unknown_bits() {
5605                         // If the channel was written by a new version and negotiated with features we don't
5606                         // understand yet, refuse to read it.
5607                         return Err(DecodeError::UnknownRequiredFeature);
5608                 }
5609
5610                 let mut secp_ctx = Secp256k1::new();
5611                 secp_ctx.seeded_randomize(&keys_source.get_secure_random_bytes());
5612
5613                 Ok(Channel {
5614                         user_id,
5615
5616                         config: config.unwrap(),
5617                         channel_id,
5618                         channel_state,
5619                         secp_ctx,
5620                         channel_value_satoshis,
5621
5622                         latest_monitor_update_id,
5623
5624                         holder_signer,
5625                         shutdown_scriptpubkey,
5626                         destination_script,
5627
5628                         cur_holder_commitment_transaction_number,
5629                         cur_counterparty_commitment_transaction_number,
5630                         value_to_self_msat,
5631
5632                         pending_inbound_htlcs,
5633                         pending_outbound_htlcs,
5634                         holding_cell_htlc_updates,
5635
5636                         resend_order,
5637
5638                         monitor_pending_funding_locked,
5639                         monitor_pending_revoke_and_ack,
5640                         monitor_pending_commitment_signed,
5641                         monitor_pending_forwards,
5642                         monitor_pending_failures,
5643                         monitor_pending_finalized_fulfills: monitor_pending_finalized_fulfills.unwrap(),
5644
5645                         pending_update_fee,
5646                         holding_cell_update_fee,
5647                         next_holder_htlc_id,
5648                         next_counterparty_htlc_id,
5649                         update_time_counter,
5650                         feerate_per_kw,
5651
5652                         #[cfg(debug_assertions)]
5653                         holder_max_commitment_tx_output: Mutex::new((0, 0)),
5654                         #[cfg(debug_assertions)]
5655                         counterparty_max_commitment_tx_output: Mutex::new((0, 0)),
5656
5657                         last_sent_closing_fee: None,
5658                         pending_counterparty_closing_signed: None,
5659                         closing_fee_limits: None,
5660                         target_closing_feerate_sats_per_kw,
5661
5662                         funding_tx_confirmed_in,
5663                         funding_tx_confirmation_height,
5664                         short_channel_id,
5665                         channel_creation_height: channel_creation_height.unwrap(),
5666
5667                         counterparty_dust_limit_satoshis,
5668                         holder_dust_limit_satoshis,
5669                         counterparty_max_htlc_value_in_flight_msat,
5670                         counterparty_selected_channel_reserve_satoshis,
5671                         counterparty_htlc_minimum_msat,
5672                         holder_htlc_minimum_msat,
5673                         counterparty_max_accepted_htlcs,
5674                         minimum_depth,
5675
5676                         counterparty_forwarding_info,
5677
5678                         channel_transaction_parameters: channel_parameters,
5679                         funding_transaction,
5680
5681                         counterparty_cur_commitment_point,
5682                         counterparty_prev_commitment_point,
5683                         counterparty_node_id,
5684
5685                         counterparty_shutdown_scriptpubkey,
5686
5687                         commitment_secrets,
5688
5689                         channel_update_status,
5690                         closing_signed_in_flight: false,
5691
5692                         announcement_sigs,
5693
5694                         #[cfg(any(test, feature = "fuzztarget"))]
5695                         next_local_commitment_tx_fee_info_cached: Mutex::new(None),
5696                         #[cfg(any(test, feature = "fuzztarget"))]
5697                         next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
5698
5699                         workaround_lnd_bug_4006: None,
5700
5701                         #[cfg(any(test, feature = "fuzztarget"))]
5702                         historical_inbound_htlc_fulfills,
5703
5704                         channel_type: channel_type.unwrap(),
5705                 })
5706         }
5707 }
5708
5709 #[cfg(test)]
5710 mod tests {
5711         use bitcoin::util::bip143;
5712         use bitcoin::consensus::encode::serialize;
5713         use bitcoin::blockdata::script::{Script, Builder};
5714         use bitcoin::blockdata::transaction::{Transaction, TxOut, SigHashType};
5715         use bitcoin::blockdata::constants::genesis_block;
5716         use bitcoin::blockdata::opcodes;
5717         use bitcoin::network::constants::Network;
5718         use bitcoin::hashes::hex::FromHex;
5719         use hex;
5720         use ln::{PaymentPreimage, PaymentHash};
5721         use ln::channelmanager::{HTLCSource, PaymentId};
5722         use ln::channel::{Channel,InboundHTLCOutput,OutboundHTLCOutput,InboundHTLCState,OutboundHTLCState,HTLCOutputInCommitment,HTLCCandidate,HTLCInitiator,TxCreationKeys};
5723         use ln::channel::MAX_FUNDING_SATOSHIS;
5724         use ln::features::InitFeatures;
5725         use ln::msgs::{ChannelUpdate, DataLossProtect, DecodeError, OptionalField, UnsignedChannelUpdate};
5726         use ln::script::ShutdownScript;
5727         use ln::chan_utils;
5728         use ln::chan_utils::{ChannelPublicKeys, HolderCommitmentTransaction, CounterpartyChannelTransactionParameters, HTLC_SUCCESS_TX_WEIGHT, HTLC_TIMEOUT_TX_WEIGHT};
5729         use chain::BestBlock;
5730         use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
5731         use chain::keysinterface::{InMemorySigner, KeysInterface, BaseSign};
5732         use chain::transaction::OutPoint;
5733         use util::config::UserConfig;
5734         use util::enforcing_trait_impls::EnforcingSigner;
5735         use util::errors::APIError;
5736         use util::test_utils;
5737         use util::test_utils::OnGetShutdownScriptpubkey;
5738         use util::logger::Logger;
5739         use bitcoin::secp256k1::{Secp256k1, Message, Signature, All};
5740         use bitcoin::secp256k1::ffi::Signature as FFISignature;
5741         use bitcoin::secp256k1::key::{SecretKey,PublicKey};
5742         use bitcoin::secp256k1::recovery::RecoverableSignature;
5743         use bitcoin::hashes::sha256::Hash as Sha256;
5744         use bitcoin::hashes::Hash;
5745         use bitcoin::hash_types::{Txid, WPubkeyHash};
5746         use core::num::NonZeroU8;
5747         use sync::Arc;
5748         use prelude::*;
5749
5750         struct TestFeeEstimator {
5751                 fee_est: u32
5752         }
5753         impl FeeEstimator for TestFeeEstimator {
5754                 fn get_est_sat_per_1000_weight(&self, _: ConfirmationTarget) -> u32 {
5755                         self.fee_est
5756                 }
5757         }
5758
5759         #[test]
5760         fn test_max_funding_satoshis() {
5761                 assert!(MAX_FUNDING_SATOSHIS <= 21_000_000 * 100_000_000,
5762                         "MAX_FUNDING_SATOSHIS is greater than all satoshis in existence");
5763         }
5764
5765         struct Keys {
5766                 signer: InMemorySigner,
5767         }
5768         impl KeysInterface for Keys {
5769                 type Signer = InMemorySigner;
5770
5771                 fn get_node_secret(&self) -> SecretKey { panic!(); }
5772                 fn get_destination_script(&self) -> Script {
5773                         let secp_ctx = Secp256k1::signing_only();
5774                         let channel_monitor_claim_key = SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap();
5775                         let channel_monitor_claim_key_hash = WPubkeyHash::hash(&PublicKey::from_secret_key(&secp_ctx, &channel_monitor_claim_key).serialize());
5776                         Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&channel_monitor_claim_key_hash[..]).into_script()
5777                 }
5778
5779                 fn get_shutdown_scriptpubkey(&self) -> ShutdownScript {
5780                         let secp_ctx = Secp256k1::signing_only();
5781                         let channel_close_key = SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap();
5782                         ShutdownScript::new_p2wpkh_from_pubkey(PublicKey::from_secret_key(&secp_ctx, &channel_close_key))
5783                 }
5784
5785                 fn get_channel_signer(&self, _inbound: bool, _channel_value_satoshis: u64) -> InMemorySigner {
5786                         self.signer.clone()
5787                 }
5788                 fn get_secure_random_bytes(&self) -> [u8; 32] { [0; 32] }
5789                 fn read_chan_signer(&self, _data: &[u8]) -> Result<Self::Signer, DecodeError> { panic!(); }
5790                 fn sign_invoice(&self, _invoice_preimage: Vec<u8>) -> Result<RecoverableSignature, ()> { panic!(); }
5791         }
5792
5793         fn public_from_secret_hex(secp_ctx: &Secp256k1<All>, hex: &str) -> PublicKey {
5794                 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode(hex).unwrap()[..]).unwrap())
5795         }
5796
5797         #[test]
5798         fn upfront_shutdown_script_incompatibility() {
5799                 let features = InitFeatures::known().clear_shutdown_anysegwit();
5800                 let non_v0_segwit_shutdown_script =
5801                         ShutdownScript::new_witness_program(NonZeroU8::new(16).unwrap(), &[0, 40]).unwrap();
5802
5803                 let seed = [42; 32];
5804                 let network = Network::Testnet;
5805                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5806                 keys_provider.expect(OnGetShutdownScriptpubkey {
5807                         returns: non_v0_segwit_shutdown_script.clone(),
5808                 });
5809
5810                 let fee_estimator = TestFeeEstimator { fee_est: 253 };
5811                 let secp_ctx = Secp256k1::new();
5812                 let node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5813                 let config = UserConfig::default();
5814                 match Channel::<EnforcingSigner>::new_outbound(&&fee_estimator, &&keys_provider, node_id, &features, 10000000, 100000, 42, &config, 0) {
5815                         Err(APIError::IncompatibleShutdownScript { script }) => {
5816                                 assert_eq!(script.into_inner(), non_v0_segwit_shutdown_script.into_inner());
5817                         },
5818                         Err(e) => panic!("Unexpected error: {:?}", e),
5819                         Ok(_) => panic!("Expected error"),
5820                 }
5821         }
5822
5823         // Check that, during channel creation, we use the same feerate in the open channel message
5824         // as we do in the Channel object creation itself.
5825         #[test]
5826         fn test_open_channel_msg_fee() {
5827                 let original_fee = 253;
5828                 let mut fee_est = TestFeeEstimator{fee_est: original_fee };
5829                 let secp_ctx = Secp256k1::new();
5830                 let seed = [42; 32];
5831                 let network = Network::Testnet;
5832                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5833
5834                 let node_a_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5835                 let config = UserConfig::default();
5836                 let node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&fee_est, &&keys_provider, node_a_node_id, &InitFeatures::known(), 10000000, 100000, 42, &config, 0).unwrap();
5837
5838                 // Now change the fee so we can check that the fee in the open_channel message is the
5839                 // same as the old fee.
5840                 fee_est.fee_est = 500;
5841                 let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.block_hash());
5842                 assert_eq!(open_channel_msg.feerate_per_kw, original_fee);
5843         }
5844
5845         #[test]
5846         fn test_holder_vs_counterparty_dust_limit() {
5847                 // Test that when calculating the local and remote commitment transaction fees, the correct
5848                 // dust limits are used.
5849                 let feeest = TestFeeEstimator{fee_est: 15000};
5850                 let secp_ctx = Secp256k1::new();
5851                 let seed = [42; 32];
5852                 let network = Network::Testnet;
5853                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5854
5855                 // Go through the flow of opening a channel between two nodes, making sure
5856                 // they have different dust limits.
5857
5858                 // Create Node A's channel pointing to Node B's pubkey
5859                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5860                 let config = UserConfig::default();
5861                 let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, &InitFeatures::known(), 10000000, 100000, 42, &config, 0).unwrap();
5862
5863                 // Create Node B's channel by receiving Node A's open_channel message
5864                 // Make sure A's dust limit is as we expect.
5865                 let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.block_hash());
5866                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
5867                 let node_b_chan = Channel::<EnforcingSigner>::new_from_req(&&feeest, &&keys_provider, node_b_node_id, &InitFeatures::known(), &open_channel_msg, 7, &config, 0).unwrap();
5868
5869                 // Node B --> Node A: accept channel, explicitly setting B's dust limit.
5870                 let mut accept_channel_msg = node_b_chan.get_accept_channel();
5871                 accept_channel_msg.dust_limit_satoshis = 546;
5872                 node_a_chan.accept_channel(&accept_channel_msg, &config, &InitFeatures::known()).unwrap();
5873                 node_a_chan.holder_dust_limit_satoshis = 1560;
5874
5875                 // Put some inbound and outbound HTLCs in A's channel.
5876                 let htlc_amount_msat = 11_092_000; // put an amount below A's effective dust limit but above B's.
5877                 node_a_chan.pending_inbound_htlcs.push(InboundHTLCOutput {
5878                         htlc_id: 0,
5879                         amount_msat: htlc_amount_msat,
5880                         payment_hash: PaymentHash(Sha256::hash(&[42; 32]).into_inner()),
5881                         cltv_expiry: 300000000,
5882                         state: InboundHTLCState::Committed,
5883                 });
5884
5885                 node_a_chan.pending_outbound_htlcs.push(OutboundHTLCOutput {
5886                         htlc_id: 1,
5887                         amount_msat: htlc_amount_msat, // put an amount below A's dust amount but above B's.
5888                         payment_hash: PaymentHash(Sha256::hash(&[43; 32]).into_inner()),
5889                         cltv_expiry: 200000000,
5890                         state: OutboundHTLCState::Committed,
5891                         source: HTLCSource::OutboundRoute {
5892                                 path: Vec::new(),
5893                                 session_priv: SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(),
5894                                 first_hop_htlc_msat: 548,
5895                                 payment_id: PaymentId([42; 32]),
5896                                 payment_secret: None,
5897                                 payee: None,
5898                         }
5899                 });
5900
5901                 // Make sure when Node A calculates their local commitment transaction, none of the HTLCs pass
5902                 // the dust limit check.
5903                 let htlc_candidate = HTLCCandidate::new(htlc_amount_msat, HTLCInitiator::LocalOffered);
5904                 let local_commit_tx_fee = node_a_chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
5905                 let local_commit_fee_0_htlcs = node_a_chan.commit_tx_fee_msat(0);
5906                 assert_eq!(local_commit_tx_fee, local_commit_fee_0_htlcs);
5907
5908                 // Finally, make sure that when Node A calculates the remote's commitment transaction fees, all
5909                 // of the HTLCs are seen to be above the dust limit.
5910                 node_a_chan.channel_transaction_parameters.is_outbound_from_holder = false;
5911                 let remote_commit_fee_3_htlcs = node_a_chan.commit_tx_fee_msat(3);
5912                 let htlc_candidate = HTLCCandidate::new(htlc_amount_msat, HTLCInitiator::LocalOffered);
5913                 let remote_commit_tx_fee = node_a_chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
5914                 assert_eq!(remote_commit_tx_fee, remote_commit_fee_3_htlcs);
5915         }
5916
5917         #[test]
5918         fn test_timeout_vs_success_htlc_dust_limit() {
5919                 // Make sure that when `next_remote_commit_tx_fee_msat` and `next_local_commit_tx_fee_msat`
5920                 // calculate the real dust limits for HTLCs (i.e. the dust limit given by the counterparty
5921                 // *plus* the fees paid for the HTLC) they don't swap `HTLC_SUCCESS_TX_WEIGHT` for
5922                 // `HTLC_TIMEOUT_TX_WEIGHT`, and vice versa.
5923                 let fee_est = TestFeeEstimator{fee_est: 253 };
5924                 let secp_ctx = Secp256k1::new();
5925                 let seed = [42; 32];
5926                 let network = Network::Testnet;
5927                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5928
5929                 let node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5930                 let config = UserConfig::default();
5931                 let mut chan = Channel::<EnforcingSigner>::new_outbound(&&fee_est, &&keys_provider, node_id, &InitFeatures::known(), 10000000, 100000, 42, &config, 0).unwrap();
5932
5933                 let commitment_tx_fee_0_htlcs = chan.commit_tx_fee_msat(0);
5934                 let commitment_tx_fee_1_htlc = chan.commit_tx_fee_msat(1);
5935
5936                 // If HTLC_SUCCESS_TX_WEIGHT and HTLC_TIMEOUT_TX_WEIGHT were swapped: then this HTLC would be
5937                 // counted as dust when it shouldn't be.
5938                 let htlc_amt_above_timeout = ((253 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + chan.holder_dust_limit_satoshis + 1) * 1000;
5939                 let htlc_candidate = HTLCCandidate::new(htlc_amt_above_timeout, HTLCInitiator::LocalOffered);
5940                 let commitment_tx_fee = chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
5941                 assert_eq!(commitment_tx_fee, commitment_tx_fee_1_htlc);
5942
5943                 // If swapped: this HTLC would be counted as non-dust when it shouldn't be.
5944                 let dust_htlc_amt_below_success = ((253 * HTLC_SUCCESS_TX_WEIGHT / 1000) + chan.holder_dust_limit_satoshis - 1) * 1000;
5945                 let htlc_candidate = HTLCCandidate::new(dust_htlc_amt_below_success, HTLCInitiator::RemoteOffered);
5946                 let commitment_tx_fee = chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
5947                 assert_eq!(commitment_tx_fee, commitment_tx_fee_0_htlcs);
5948
5949                 chan.channel_transaction_parameters.is_outbound_from_holder = false;
5950
5951                 // If swapped: this HTLC would be counted as non-dust when it shouldn't be.
5952                 let dust_htlc_amt_above_timeout = ((253 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + chan.counterparty_dust_limit_satoshis + 1) * 1000;
5953                 let htlc_candidate = HTLCCandidate::new(dust_htlc_amt_above_timeout, HTLCInitiator::LocalOffered);
5954                 let commitment_tx_fee = chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
5955                 assert_eq!(commitment_tx_fee, commitment_tx_fee_0_htlcs);
5956
5957                 // If swapped: this HTLC would be counted as dust when it shouldn't be.
5958                 let htlc_amt_below_success = ((253 * HTLC_SUCCESS_TX_WEIGHT / 1000) + chan.counterparty_dust_limit_satoshis - 1) * 1000;
5959                 let htlc_candidate = HTLCCandidate::new(htlc_amt_below_success, HTLCInitiator::RemoteOffered);
5960                 let commitment_tx_fee = chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
5961                 assert_eq!(commitment_tx_fee, commitment_tx_fee_1_htlc);
5962         }
5963
5964         #[test]
5965         fn channel_reestablish_no_updates() {
5966                 let feeest = TestFeeEstimator{fee_est: 15000};
5967                 let logger = test_utils::TestLogger::new();
5968                 let secp_ctx = Secp256k1::new();
5969                 let seed = [42; 32];
5970                 let network = Network::Testnet;
5971                 let best_block = BestBlock::from_genesis(network);
5972                 let chain_hash = best_block.block_hash();
5973                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5974
5975                 // Go through the flow of opening a channel between two nodes.
5976
5977                 // Create Node A's channel pointing to Node B's pubkey
5978                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5979                 let config = UserConfig::default();
5980                 let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, &InitFeatures::known(), 10000000, 100000, 42, &config, 0).unwrap();
5981
5982                 // Create Node B's channel by receiving Node A's open_channel message
5983                 let open_channel_msg = node_a_chan.get_open_channel(chain_hash);
5984                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
5985                 let mut node_b_chan = Channel::<EnforcingSigner>::new_from_req(&&feeest, &&keys_provider, node_b_node_id, &InitFeatures::known(), &open_channel_msg, 7, &config, 0).unwrap();
5986
5987                 // Node B --> Node A: accept channel
5988                 let accept_channel_msg = node_b_chan.get_accept_channel();
5989                 node_a_chan.accept_channel(&accept_channel_msg, &config, &InitFeatures::known()).unwrap();
5990
5991                 // Node A --> Node B: funding created
5992                 let output_script = node_a_chan.get_funding_redeemscript();
5993                 let tx = Transaction { version: 1, lock_time: 0, input: Vec::new(), output: vec![TxOut {
5994                         value: 10000000, script_pubkey: output_script.clone(),
5995                 }]};
5996                 let funding_outpoint = OutPoint{ txid: tx.txid(), index: 0 };
5997                 let funding_created_msg = node_a_chan.get_outbound_funding_created(tx.clone(), funding_outpoint, &&logger).unwrap();
5998                 let (funding_signed_msg, _) = node_b_chan.funding_created(&funding_created_msg, best_block, &&logger).unwrap();
5999
6000                 // Node B --> Node A: funding signed
6001                 let _ = node_a_chan.funding_signed(&funding_signed_msg, best_block, &&logger);
6002
6003                 // Now disconnect the two nodes and check that the commitment point in
6004                 // Node B's channel_reestablish message is sane.
6005                 node_b_chan.remove_uncommitted_htlcs_and_mark_paused(&&logger);
6006                 let msg = node_b_chan.get_channel_reestablish(&&logger);
6007                 assert_eq!(msg.next_local_commitment_number, 1); // now called next_commitment_number
6008                 assert_eq!(msg.next_remote_commitment_number, 0); // now called next_revocation_number
6009                 match msg.data_loss_protect {
6010                         OptionalField::Present(DataLossProtect { your_last_per_commitment_secret, .. }) => {
6011                                 assert_eq!(your_last_per_commitment_secret, [0; 32]);
6012                         },
6013                         _ => panic!()
6014                 }
6015
6016                 // Check that the commitment point in Node A's channel_reestablish message
6017                 // is sane.
6018                 node_a_chan.remove_uncommitted_htlcs_and_mark_paused(&&logger);
6019                 let msg = node_a_chan.get_channel_reestablish(&&logger);
6020                 assert_eq!(msg.next_local_commitment_number, 1); // now called next_commitment_number
6021                 assert_eq!(msg.next_remote_commitment_number, 0); // now called next_revocation_number
6022                 match msg.data_loss_protect {
6023                         OptionalField::Present(DataLossProtect { your_last_per_commitment_secret, .. }) => {
6024                                 assert_eq!(your_last_per_commitment_secret, [0; 32]);
6025                         },
6026                         _ => panic!()
6027                 }
6028         }
6029
6030         #[test]
6031         fn channel_update() {
6032                 let feeest = TestFeeEstimator{fee_est: 15000};
6033                 let secp_ctx = Secp256k1::new();
6034                 let seed = [42; 32];
6035                 let network = Network::Testnet;
6036                 let chain_hash = genesis_block(network).header.block_hash();
6037                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
6038
6039                 // Create a channel.
6040                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
6041                 let config = UserConfig::default();
6042                 let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, &InitFeatures::known(), 10000000, 100000, 42, &config, 0).unwrap();
6043                 assert!(node_a_chan.counterparty_forwarding_info.is_none());
6044                 assert_eq!(node_a_chan.holder_htlc_minimum_msat, 1); // the default
6045                 assert!(node_a_chan.counterparty_forwarding_info().is_none());
6046
6047                 // Make sure that receiving a channel update will update the Channel as expected.
6048                 let update = ChannelUpdate {
6049                         contents: UnsignedChannelUpdate {
6050                                 chain_hash,
6051                                 short_channel_id: 0,
6052                                 timestamp: 0,
6053                                 flags: 0,
6054                                 cltv_expiry_delta: 100,
6055                                 htlc_minimum_msat: 5,
6056                                 htlc_maximum_msat: OptionalField::Absent,
6057                                 fee_base_msat: 110,
6058                                 fee_proportional_millionths: 11,
6059                                 excess_data: Vec::new(),
6060                         },
6061                         signature: Signature::from(unsafe { FFISignature::new() })
6062                 };
6063                 node_a_chan.channel_update(&update).unwrap();
6064
6065                 // The counterparty can send an update with a higher minimum HTLC, but that shouldn't
6066                 // change our official htlc_minimum_msat.
6067                 assert_eq!(node_a_chan.holder_htlc_minimum_msat, 1);
6068                 match node_a_chan.counterparty_forwarding_info() {
6069                         Some(info) => {
6070                                 assert_eq!(info.cltv_expiry_delta, 100);
6071                                 assert_eq!(info.fee_base_msat, 110);
6072                                 assert_eq!(info.fee_proportional_millionths, 11);
6073                         },
6074                         None => panic!("expected counterparty forwarding info to be Some")
6075                 }
6076         }
6077
6078         #[test]
6079         fn outbound_commitment_test() {
6080                 // Test vectors from BOLT 3 Appendix C:
6081                 let feeest = TestFeeEstimator{fee_est: 15000};
6082                 let logger : Arc<Logger> = Arc::new(test_utils::TestLogger::new());
6083                 let secp_ctx = Secp256k1::new();
6084
6085                 let mut signer = InMemorySigner::new(
6086                         &secp_ctx,
6087                         SecretKey::from_slice(&hex::decode("30ff4956bbdd3222d44cc5e8a1261dab1e07957bdac5ae88fe3261ef321f3749").unwrap()[..]).unwrap(),
6088                         SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(),
6089                         SecretKey::from_slice(&hex::decode("1111111111111111111111111111111111111111111111111111111111111111").unwrap()[..]).unwrap(),
6090                         SecretKey::from_slice(&hex::decode("3333333333333333333333333333333333333333333333333333333333333333").unwrap()[..]).unwrap(),
6091                         SecretKey::from_slice(&hex::decode("1111111111111111111111111111111111111111111111111111111111111111").unwrap()[..]).unwrap(),
6092
6093                         // These aren't set in the test vectors:
6094                         [0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff],
6095                         10_000_000,
6096                         [0; 32]
6097                 );
6098
6099                 assert_eq!(signer.pubkeys().funding_pubkey.serialize()[..],
6100                                 hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]);
6101                 let keys_provider = Keys { signer: signer.clone() };
6102
6103                 let counterparty_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
6104                 let mut config = UserConfig::default();
6105                 config.channel_options.announced_channel = false;
6106                 let mut chan = Channel::<InMemorySigner>::new_outbound(&&feeest, &&keys_provider, counterparty_node_id, &InitFeatures::known(), 10_000_000, 100000, 42, &config, 0).unwrap(); // Nothing uses their network key in this test
6107                 chan.holder_dust_limit_satoshis = 546;
6108                 chan.counterparty_selected_channel_reserve_satoshis = Some(0); // Filled in in accept_channel
6109
6110                 let funding_info = OutPoint{ txid: Txid::from_hex("8984484a580b825b9972d7adb15050b3ab624ccd731946b3eeddb92f4e7ef6be").unwrap(), index: 0 };
6111
6112                 let counterparty_pubkeys = ChannelPublicKeys {
6113                         funding_pubkey: public_from_secret_hex(&secp_ctx, "1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13"),
6114                         revocation_basepoint: PublicKey::from_slice(&hex::decode("02466d7fcae563e5cb09a0d1870bb580344804617879a14949cf22285f1bae3f27").unwrap()[..]).unwrap(),
6115                         payment_point: public_from_secret_hex(&secp_ctx, "4444444444444444444444444444444444444444444444444444444444444444"),
6116                         delayed_payment_basepoint: public_from_secret_hex(&secp_ctx, "1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13"),
6117                         htlc_basepoint: public_from_secret_hex(&secp_ctx, "4444444444444444444444444444444444444444444444444444444444444444")
6118                 };
6119                 chan.channel_transaction_parameters.counterparty_parameters = Some(
6120                         CounterpartyChannelTransactionParameters {
6121                                 pubkeys: counterparty_pubkeys.clone(),
6122                                 selected_contest_delay: 144
6123                         });
6124                 chan.channel_transaction_parameters.funding_outpoint = Some(funding_info);
6125                 signer.ready_channel(&chan.channel_transaction_parameters);
6126
6127                 assert_eq!(counterparty_pubkeys.payment_point.serialize()[..],
6128                            hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
6129
6130                 assert_eq!(counterparty_pubkeys.funding_pubkey.serialize()[..],
6131                            hex::decode("030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c1").unwrap()[..]);
6132
6133                 assert_eq!(counterparty_pubkeys.htlc_basepoint.serialize()[..],
6134                            hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
6135
6136                 // We can't just use build_holder_transaction_keys here as the per_commitment_secret is not
6137                 // derived from a commitment_seed, so instead we copy it here and call
6138                 // build_commitment_transaction.
6139                 let delayed_payment_base = &chan.holder_signer.pubkeys().delayed_payment_basepoint;
6140                 let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
6141                 let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
6142                 let htlc_basepoint = &chan.holder_signer.pubkeys().htlc_basepoint;
6143                 let keys = TxCreationKeys::derive_new(&secp_ctx, &per_commitment_point, delayed_payment_base, htlc_basepoint, &counterparty_pubkeys.revocation_basepoint, &counterparty_pubkeys.htlc_basepoint).unwrap();
6144
6145                 macro_rules! test_commitment {
6146                         ( $counterparty_sig_hex: expr, $sig_hex: expr, $tx_hex: expr, {
6147                                 $( { $htlc_idx: expr, $counterparty_htlc_sig_hex: expr, $htlc_sig_hex: expr, $htlc_tx_hex: expr } ), *
6148                         } ) => { {
6149                                 let (commitment_tx, htlcs): (_, Vec<HTLCOutputInCommitment>) = {
6150                                         let mut res = chan.build_commitment_transaction(0xffffffffffff - 42, &keys, true, false, &logger);
6151
6152                                         let htlcs = res.3.drain(..)
6153                                                 .filter_map(|(htlc, _)| if htlc.transaction_output_index.is_some() { Some(htlc) } else { None })
6154                                                 .collect();
6155                                         (res.0, htlcs)
6156                                 };
6157                                 let trusted_tx = commitment_tx.trust();
6158                                 let unsigned_tx = trusted_tx.built_transaction();
6159                                 let redeemscript = chan.get_funding_redeemscript();
6160                                 let counterparty_signature = Signature::from_der(&hex::decode($counterparty_sig_hex).unwrap()[..]).unwrap();
6161                                 let sighash = unsigned_tx.get_sighash_all(&redeemscript, chan.channel_value_satoshis);
6162                                 secp_ctx.verify(&sighash, &counterparty_signature, chan.counterparty_funding_pubkey()).unwrap();
6163
6164                                 let mut per_htlc: Vec<(HTLCOutputInCommitment, Option<Signature>)> = Vec::new();
6165                                 per_htlc.clear(); // Don't warn about excess mut for no-HTLC calls
6166                                 let mut counterparty_htlc_sigs = Vec::new();
6167                                 counterparty_htlc_sigs.clear(); // Don't warn about excess mut for no-HTLC calls
6168                                 $({
6169                                         let remote_signature = Signature::from_der(&hex::decode($counterparty_htlc_sig_hex).unwrap()[..]).unwrap();
6170                                         per_htlc.push((htlcs[$htlc_idx].clone(), Some(remote_signature)));
6171                                         counterparty_htlc_sigs.push(remote_signature);
6172                                 })*
6173                                 assert_eq!(htlcs.len(), per_htlc.len());
6174
6175                                 let holder_commitment_tx = HolderCommitmentTransaction::new(
6176                                         commitment_tx.clone(),
6177                                         counterparty_signature,
6178                                         counterparty_htlc_sigs,
6179                                         &chan.holder_signer.pubkeys().funding_pubkey,
6180                                         chan.counterparty_funding_pubkey()
6181                                 );
6182                                 let (holder_sig, htlc_sigs) = signer.sign_holder_commitment_and_htlcs(&holder_commitment_tx, &secp_ctx).unwrap();
6183                                 assert_eq!(Signature::from_der(&hex::decode($sig_hex).unwrap()[..]).unwrap(), holder_sig, "holder_sig");
6184
6185                                 let funding_redeemscript = chan.get_funding_redeemscript();
6186                                 let tx = holder_commitment_tx.add_holder_sig(&funding_redeemscript, holder_sig);
6187                                 assert_eq!(serialize(&tx)[..], hex::decode($tx_hex).unwrap()[..], "tx");
6188
6189                                 // ((htlc, counterparty_sig), (index, holder_sig))
6190                                 let mut htlc_sig_iter = holder_commitment_tx.htlcs().iter().zip(&holder_commitment_tx.counterparty_htlc_sigs).zip(htlc_sigs.iter().enumerate());
6191
6192                                 $({
6193                                         let remote_signature = Signature::from_der(&hex::decode($counterparty_htlc_sig_hex).unwrap()[..]).unwrap();
6194
6195                                         let ref htlc = htlcs[$htlc_idx];
6196                                         let htlc_tx = chan_utils::build_htlc_transaction(&unsigned_tx.txid, chan.feerate_per_kw,
6197                                                 chan.get_counterparty_selected_contest_delay().unwrap(),
6198                                                 &htlc, &keys.broadcaster_delayed_payment_key, &keys.revocation_key);
6199                                         let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys);
6200                                         let htlc_sighash = Message::from_slice(&bip143::SigHashCache::new(&htlc_tx).signature_hash(0, &htlc_redeemscript, htlc.amount_msat / 1000, SigHashType::All)[..]).unwrap();
6201                                         secp_ctx.verify(&htlc_sighash, &remote_signature, &keys.countersignatory_htlc_key).unwrap();
6202
6203                                         let mut preimage: Option<PaymentPreimage> = None;
6204                                         if !htlc.offered {
6205                                                 for i in 0..5 {
6206                                                         let out = PaymentHash(Sha256::hash(&[i; 32]).into_inner());
6207                                                         if out == htlc.payment_hash {
6208                                                                 preimage = Some(PaymentPreimage([i; 32]));
6209                                                         }
6210                                                 }
6211
6212                                                 assert!(preimage.is_some());
6213                                         }
6214
6215                                         let htlc_sig = htlc_sig_iter.next().unwrap();
6216                                         assert_eq!((htlc_sig.0).0.transaction_output_index, Some($htlc_idx), "output index");
6217
6218                                         let signature = Signature::from_der(&hex::decode($htlc_sig_hex).unwrap()[..]).unwrap();
6219                                         assert_eq!(signature, *(htlc_sig.1).1, "htlc sig");
6220                                         let index = (htlc_sig.1).0;
6221                                         let channel_parameters = chan.channel_transaction_parameters.as_holder_broadcastable();
6222                                         let trusted_tx = holder_commitment_tx.trust();
6223                                         assert_eq!(serialize(&trusted_tx.get_signed_htlc_tx(&channel_parameters, index, &(htlc_sig.0).1, (htlc_sig.1).1, &preimage))[..],
6224                                                         hex::decode($htlc_tx_hex).unwrap()[..], "htlc tx");
6225                                 })*
6226                                 assert!(htlc_sig_iter.next().is_none());
6227                         } }
6228                 }
6229
6230                 // simple commitment tx with no HTLCs
6231                 chan.value_to_self_msat = 7000000000;
6232
6233                 test_commitment!("3045022100c3127b33dcc741dd6b05b1e63cbd1a9a7d816f37af9b6756fa2376b056f032370220408b96279808fe57eb7e463710804cdf4f108388bc5cf722d8c848d2c7f9f3b0",
6234                                                  "30440220616210b2cc4d3afb601013c373bbd8aac54febd9f15400379a8cb65ce7deca60022034236c010991beb7ff770510561ae8dc885b8d38d1947248c38f2ae055647142",
6235                                                  "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", {});
6236
6237                 chan.pending_inbound_htlcs.push({
6238                         let mut out = InboundHTLCOutput{
6239                                 htlc_id: 0,
6240                                 amount_msat: 1000000,
6241                                 cltv_expiry: 500,
6242                                 payment_hash: PaymentHash([0; 32]),
6243                                 state: InboundHTLCState::Committed,
6244                         };
6245                         out.payment_hash.0 = Sha256::hash(&hex::decode("0000000000000000000000000000000000000000000000000000000000000000").unwrap()).into_inner();
6246                         out
6247                 });
6248                 chan.pending_inbound_htlcs.push({
6249                         let mut out = InboundHTLCOutput{
6250                                 htlc_id: 1,
6251                                 amount_msat: 2000000,
6252                                 cltv_expiry: 501,
6253                                 payment_hash: PaymentHash([0; 32]),
6254                                 state: InboundHTLCState::Committed,
6255                         };
6256                         out.payment_hash.0 = Sha256::hash(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()).into_inner();
6257                         out
6258                 });
6259                 chan.pending_outbound_htlcs.push({
6260                         let mut out = OutboundHTLCOutput{
6261                                 htlc_id: 2,
6262                                 amount_msat: 2000000,
6263                                 cltv_expiry: 502,
6264                                 payment_hash: PaymentHash([0; 32]),
6265                                 state: OutboundHTLCState::Committed,
6266                                 source: HTLCSource::dummy(),
6267                         };
6268                         out.payment_hash.0 = Sha256::hash(&hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap()).into_inner();
6269                         out
6270                 });
6271                 chan.pending_outbound_htlcs.push({
6272                         let mut out = OutboundHTLCOutput{
6273                                 htlc_id: 3,
6274                                 amount_msat: 3000000,
6275                                 cltv_expiry: 503,
6276                                 payment_hash: PaymentHash([0; 32]),
6277                                 state: OutboundHTLCState::Committed,
6278                                 source: HTLCSource::dummy(),
6279                         };
6280                         out.payment_hash.0 = Sha256::hash(&hex::decode("0303030303030303030303030303030303030303030303030303030303030303").unwrap()).into_inner();
6281                         out
6282                 });
6283                 chan.pending_inbound_htlcs.push({
6284                         let mut out = InboundHTLCOutput{
6285                                 htlc_id: 4,
6286                                 amount_msat: 4000000,
6287                                 cltv_expiry: 504,
6288                                 payment_hash: PaymentHash([0; 32]),
6289                                 state: InboundHTLCState::Committed,
6290                         };
6291                         out.payment_hash.0 = Sha256::hash(&hex::decode("0404040404040404040404040404040404040404040404040404040404040404").unwrap()).into_inner();
6292                         out
6293                 });
6294
6295                 // commitment tx with all five HTLCs untrimmed (minimum feerate)
6296                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6297                 chan.feerate_per_kw = 0;
6298
6299                 test_commitment!("3044022009b048187705a8cbc9ad73adbe5af148c3d012e1f067961486c822c7af08158c022006d66f3704cfab3eb2dc49dae24e4aa22a6910fc9b424007583204e3621af2e5",
6300                                  "304402206fc2d1f10ea59951eefac0b4b7c396a3c3d87b71ff0b019796ef4535beaf36f902201765b0181e514d04f4c8ad75659d7037be26cdb3f8bb6f78fe61decef484c3ea",
6301                                  "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", {
6302
6303                                   { 0,
6304                                   "3045022100d9e29616b8f3959f1d3d7f7ce893ffedcdc407717d0de8e37d808c91d3a7c50d022078c3033f6d00095c8720a4bc943c1b45727818c082e4e3ddbc6d3116435b624b",
6305                                   "30440220636de5682ef0c5b61f124ec74e8aa2461a69777521d6998295dcea36bc3338110220165285594b23c50b28b82df200234566628a27bcd17f7f14404bd865354eb3ce",
6306                                   "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" },
6307
6308                                   { 1,
6309                                   "30440220649fe8b20e67e46cbb0d09b4acea87dbec001b39b08dee7bdd0b1f03922a8640022037c462dff79df501cecfdb12ea7f4de91f99230bb544726f6e04527b1f896004",
6310                                   "3045022100803159dee7935dba4a1d36a61055ce8fd62caa528573cc221ae288515405a252022029c59e7cffce374fe860100a4a63787e105c3cf5156d40b12dd53ff55ac8cf3f",
6311                                   "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" },
6312
6313                                   { 2,
6314                                   "30440220770fc321e97a19f38985f2e7732dd9fe08d16a2efa4bcbc0429400a447faf49102204d40b417f3113e1b0944ae0986f517564ab4acd3d190503faf97a6e420d43352",
6315                                   "3045022100a437cc2ce77400ecde441b3398fea3c3ad8bdad8132be818227fe3c5b8345989022069d45e7fa0ae551ec37240845e2c561ceb2567eacf3076a6a43a502d05865faa",
6316                                   "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" },
6317
6318                                   { 3,
6319                                   "304402207bcbf4f60a9829b05d2dbab84ed593e0291836be715dc7db6b72a64caf646af802201e489a5a84f7c5cc130398b841d138d031a5137ac8f4c49c770a4959dc3c1363",
6320                                   "304402203121d9b9c055f354304b016a36662ee99e1110d9501cb271b087ddb6f382c2c80220549882f3f3b78d9c492de47543cb9a697cecc493174726146536c5954dac7487",
6321                                   "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" },
6322
6323                                   { 4,
6324                                   "3044022076dca5cb81ba7e466e349b7128cdba216d4d01659e29b96025b9524aaf0d1899022060de85697b88b21c749702b7d2cfa7dfeaa1f472c8f1d7d9c23f2bf968464b87",
6325                                   "3045022100d9080f103cc92bac15ec42464a95f070c7fb6925014e673ee2ea1374d36a7f7502200c65294d22eb20d48564954d5afe04a385551919d8b2ddb4ae2459daaeee1d95",
6326                                   "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" }
6327                 } );
6328
6329                 // commitment tx with seven outputs untrimmed (maximum feerate)
6330                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6331                 chan.feerate_per_kw = 647;
6332
6333                 test_commitment!("3045022100a135f9e8a5ed25f7277446c67956b00ce6f610ead2bdec2c2f686155b7814772022059f1f6e1a8b336a68efcc1af3fe4d422d4827332b5b067501b099c47b7b5b5ee",
6334                                  "30450221009ec15c687898bb4da8b3a833e5ab8bfc51ec6e9202aaa8e66611edfd4a85ed1102203d7183e45078b9735c93450bc3415d3e5a8c576141a711ec6ddcb4a893926bb7",
6335                                  "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", {
6336
6337                                   { 0,
6338                                   "30450221008437627f9ad84ac67052e2a414a4367b8556fd1f94d8b02590f89f50525cd33502205b9c21ff6e7fc864f2352746ad8ba59182510819acb644e25b8a12fc37bbf24f",
6339                                   "30440220344b0deb055230d01703e6c7acd45853c4af2328b49b5d8af4f88a060733406602202ea64f2a43d5751edfe75503cbc35a62e3141b5ed032fa03360faf4ca66f670b",
6340                                   "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" },
6341
6342                                   { 1,
6343                                   "304402205a67f92bf6845cf2892b48d874ac1daf88a36495cf8a06f93d83180d930a6f75022031da1621d95c3f335cc06a3056cf960199dae600b7cf89088f65fc53cdbef28c",
6344                                   "30450221009e5e3822b0185c6799a95288c597b671d6cc69ab80f43740f00c6c3d0752bdda02206da947a74bd98f3175324dc56fdba86cc783703a120a6f0297537e60632f4c7f",
6345                                   "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" },
6346
6347                                   { 2,
6348                                   "30440220437e21766054a3eef7f65690c5bcfa9920babbc5af92b819f772f6ea96df6c7402207173622024bd97328cfb26c6665e25c2f5d67c319443ccdc60c903217005d8c8",
6349                                   "3045022100fcfc47e36b712624677626cef3dc1d67f6583bd46926a6398fe6b00b0c9a37760220525788257b187fc775c6370d04eadf34d06f3650a63f8df851cee0ecb47a1673",
6350                                   "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" },
6351
6352                                   { 3,
6353                                   "304402207436e10737e4df499fc051686d3e11a5bb2310e4d1f1e691d287cef66514791202207cb58e71a6b7a42dd001b7e3ae672ea4f71ea3e1cd412b742e9124abb0739c64",
6354                                   "3045022100e78211b8409afb7255ffe37337da87f38646f1faebbdd61bc1920d69e3ead67a02201a626305adfcd16bfb7e9340928d9b6305464eab4aa4c4a3af6646e9b9f69dee",
6355                                   "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" },
6356
6357                                   { 4,
6358                                   "30450221009acd6a827a76bfee50806178dfe0495cd4e1d9c58279c194c7b01520fe68cb8d022024d439047c368883e570997a7d40f0b430cb5a742f507965e7d3063ae3feccca",
6359                                   "3044022048762cf546bbfe474f1536365ea7c416e3c0389d60558bc9412cb148fb6ab68202207215d7083b75c96ff9d2b08c59c34e287b66820f530b486a9aa4cdd9c347d5b9",
6360                                   "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" }
6361                 } );
6362
6363                 // commitment tx with six outputs untrimmed (minimum feerate)
6364                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6365                 chan.feerate_per_kw = 648;
6366
6367                 test_commitment!("304402203948f900a5506b8de36a4d8502f94f21dd84fd9c2314ab427d52feaa7a0a19f2022059b6a37a4adaa2c5419dc8aea63c6e2a2ec4c4bde46207f6dc1fcd22152fc6e5",
6368                                  "3045022100b15f72908ba3382a34ca5b32519240a22300cc6015b6f9418635fb41f3d01d8802207adb331b9ed1575383dca0f2355e86c173802feecf8298fbea53b9d4610583e9",
6369                                  "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", {
6370
6371                                   { 0,
6372                                   "3045022100a031202f3be94678f0e998622ee95ebb6ada8da1e9a5110228b5e04a747351e4022010ca6a21e18314ed53cfaae3b1f51998552a61a468e596368829a50ce40110e0",
6373                                   "304502210097e1873b57267730154595187a34949d3744f52933070c74757005e61ce2112e02204ecfba2aa42d4f14bdf8bad4206bb97217b702e6c433e0e1b0ce6587e6d46ec6",
6374                                   "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" },
6375
6376                                   { 1,
6377                                   "304402202361012a634aee7835c5ecdd6413dcffa8f404b7e77364c792cff984e4ee71e90220715c5e90baa08daa45a7439b1ee4fa4843ed77b19c058240b69406606d384124",
6378                                   "3044022019de73b00f1d818fb388e83b2c8c31f6bce35ac624e215bc12f88f9dc33edf48022006ff814bb9f700ee6abc3294e146fac3efd4f13f0005236b41c0a946ee00c9ae",
6379                                   "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" },
6380
6381                                   { 2,
6382                                   "304402207e8e82cd71ed4febeb593732c260456836e97d81896153ecd2b3cf320ca6861702202dd4a30f68f98ced7cc56a36369ac1fdd978248c5ff4ed204fc00cc625532989",
6383                                   "3045022100bd0be6100c4fd8f102ec220e1b053e4c4e2ecca25615490150007b40d314dc3902201a1e0ea266965b43164d9e6576f58fa6726d42883dd1c3996d2925c2e2260796",
6384                                   "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" },
6385
6386                                   { 3,
6387                                   "3044022024cd52e4198c8ae0e414a86d86b5a65ea7450f2eb4e783096736d93395eca5ce022078f0094745b45be4d4b2b04dd5978c9e66ba49109e5704403e84aaf5f387d6be",
6388                                   "3045022100bbfb9d0a946d420807c86e985d636cceb16e71c3694ed186316251a00cbd807202207773223f9a337e145f64673825be9b30d07ef1542c82188b264bedcf7cda78c6",
6389                                   "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" }
6390                 } );
6391
6392                 // commitment tx with six outputs untrimmed (maximum feerate)
6393                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6394                 chan.feerate_per_kw = 2069;
6395
6396                 test_commitment!("304502210090b96a2498ce0c0f2fadbec2aab278fed54c1a7838df793ec4d2c78d96ec096202204fdd439c50f90d483baa7b68feeef4bd33bc277695405447bcd0bfb2ca34d7bc",
6397                                  "3045022100ad9a9bbbb75d506ca3b716b336ee3cf975dd7834fcf129d7dd188146eb58a8b4022061a759ee417339f7fe2ea1e8deb83abb6a74db31a09b7648a932a639cda23e33",
6398                                  "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", {
6399
6400                                   { 0,
6401                                   "3045022100f33513ee38abf1c582876f921f8fddc06acff48e04515532a32d3938de938ffd02203aa308a2c1863b7d6fdf53159a1465bf2e115c13152546cc5d74483ceaa7f699",
6402                                   "3045022100a637902a5d4c9ba9e7c472a225337d5aac9e2e3f6744f76e237132e7619ba0400220035c60d784a031c0d9f6df66b7eab8726a5c25397399ee4aa960842059eb3f9d",
6403                                   "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" },
6404
6405                                   { 1,
6406                                   "3045022100ce07682cf4b90093c22dc2d9ab2a77ad6803526b655ef857221cc96af5c9e0bf02200f501cee22e7a268af40b555d15a8237c9f36ad67ef1841daf9f6a0267b1e6df",
6407                                   "3045022100e57e46234f8782d3ff7aa593b4f7446fb5316c842e693dc63ee324fd49f6a1c302204a2f7b44c48bd26e1554422afae13153eb94b29d3687b733d18930615fb2db61",
6408                                   "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" },
6409
6410                                   { 2,
6411                                   "3045022100e3e35492e55f82ec0bc2f317ffd7a486d1f7024330fe9743c3559fc39f32ef0c02203d1d4db651fc388a91d5ad8ecdd8e83673063bc8eefe27cfd8c189090e3a23e0",
6412                                   "3044022068613fb1b98eb3aec7f44c5b115b12343c2f066c4277c82b5f873dfe68f37f50022028109b4650f3f528ca4bfe9a467aff2e3e43893b61b5159157119d5d95cf1c18",
6413                                   "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" },
6414
6415                                   { 3,
6416                                   "304402207475aeb0212ef9bf5130b60937817ad88c9a87976988ef1f323f026148cc4a850220739fea17ad3257dcad72e509c73eebe86bee30b178467b9fdab213d631b109df",
6417                                   "3045022100d315522e09e7d53d2a659a79cb67fef56d6c4bddf3f46df6772d0d20a7beb7c8022070bcc17e288607b6a72be0bd83368bb6d53488db266c1cdb4d72214e4f02ac33",
6418                                   "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" }
6419                 } );
6420
6421                 // commitment tx with five outputs untrimmed (minimum feerate)
6422                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6423                 chan.feerate_per_kw = 2070;
6424
6425                 test_commitment!("304402204ca1ba260dee913d318271d86e10ca0f5883026fb5653155cff600fb40895223022037b145204b7054a40e08bb1fefbd826f827b40838d3e501423bcc57924bcb50c",
6426                                  "3044022001014419b5ba00e083ac4e0a85f19afc848aacac2d483b4b525d15e2ae5adbfe022015ebddad6ee1e72b47cb09f3e78459da5be01ccccd95dceca0e056a00cc773c1",
6427                                  "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", {
6428
6429                                   { 0,
6430                                   "304402205f6b6d12d8d2529fb24f4445630566cf4abbd0f9330ab6c2bdb94222d6a2a0c502202f556258ae6f05b193749e4c541dfcc13b525a5422f6291f073f15617ba8579b",
6431                                   "30440220150b11069454da70caf2492ded9e0065c9a57f25ac2a4c52657b1d15b6c6ed85022068a38833b603c8892717206383611bad210f1cbb4b1f87ea29c6c65b9e1cb3e5",
6432                                   "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" },
6433
6434                                   { 1,
6435                                   "3045022100f960dfb1c9aee7ce1437efa65b523e399383e8149790e05d8fed27ff6e42fe0002202fe8613e062ffe0b0c518cc4101fba1c6de70f64a5bcc7ae663f2efae43b8546",
6436                                   "30450221009a6ed18e6873bc3644332a6ee21c152a5b102821865350df7a8c74451a51f9f2022050d801fb4895d7d7fbf452824c0168347f5c0cbe821cf6a97a63af5b8b2563c6",
6437                                   "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" },
6438
6439                                   { 2,
6440                                   "3045022100ae5fc7717ae684bc1fcf9020854e5dbe9842c9e7472879ac06ff95ac2bb10e4e022057728ada4c00083a3e65493fb5d50a232165948a1a0f530ef63185c2c8c56504",
6441                                   "30440220408ad3009827a8fccf774cb285587686bfb2ed041f89a89453c311ce9c8ee0f902203c7392d9f8306d3a46522a66bd2723a7eb2628cb2d9b34d4c104f1766bf37502",
6442                                   "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" }
6443                 } );
6444
6445                 // commitment tx with five outputs untrimmed (maximum feerate)
6446                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6447                 chan.feerate_per_kw = 2194;
6448
6449                 test_commitment!("304402204bb3d6e279d71d9da414c82de42f1f954267c762b2e2eb8b76bc3be4ea07d4b0022014febc009c5edc8c3fc5d94015de163200f780046f1c293bfed8568f08b70fb3",
6450                                  "3044022072c2e2b1c899b2242656a537dde2892fa3801be0d6df0a87836c550137acde8302201654aa1974d37a829083c3ba15088689f30b56d6a4f6cb14c7bad0ee3116d398",
6451                                  "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", {
6452
6453                                   { 0,
6454                                   "3045022100939726680351a7856c1bc386d4a1f422c7d29bd7b56afc139570f508474e6c40022023175a799ccf44c017fbaadb924c40b2a12115a5b7d0dfd3228df803a2de8450",
6455                                   "304502210099c98c2edeeee6ec0fb5f3bea8b79bb016a2717afa9b5072370f34382de281d302206f5e2980a995e045cf90a547f0752a7ee99d48547bc135258fe7bc07e0154301",
6456                                   "02000000000101153cd825fdb3aa624bfe513e8031d5d08c5e582fb3d1d1fe8faf27d3eed410cd0000000000000000000122020000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e0500483045022100939726680351a7856c1bc386d4a1f422c7d29bd7b56afc139570f508474e6c40022023175a799ccf44c017fbaadb924c40b2a12115a5b7d0dfd3228df803a2de84500148304502210099c98c2edeeee6ec0fb5f3bea8b79bb016a2717afa9b5072370f34382de281d302206f5e2980a995e045cf90a547f0752a7ee99d48547bc135258fe7bc07e015430101008576a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c820120876475527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae67a914b43e1b38138a41b37f7cd9a1d274bc63e3a9b5d188ac6868f6010000" },
6457
6458                                   { 1,
6459                                   "3044022021bb883bf324553d085ba2e821cad80c28ef8b303dbead8f98e548783c02d1600220638f9ef2a9bba25869afc923f4b5dc38be3bb459f9efa5d869392d5f7779a4a0",
6460                                   "3045022100fd85bd7697b89c08ec12acc8ba89b23090637d83abd26ca37e01ae93e67c367302202b551fe69386116c47f984aab9c8dfd25d864dcde5d3389cfbef2447a85c4b77",
6461                                   "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" },
6462
6463                                   { 2,
6464                                   "3045022100c9e6f0454aa598b905a35e641a70cc9f67b5f38cc4b00843a041238c4a9f1c4a0220260a2822a62da97e44583e837245995ca2e36781769c52f19e498efbdcca262b",
6465                                   "30450221008a9f2ea24cd455c2b64c1472a5fa83865b0a5f49a62b661801e884cf2849af8302204d44180e50bf6adfcf1c1e581d75af91aba4e28681ce4a5ee5f3cbf65eca10f3",
6466                                   "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" }
6467                 } );
6468
6469                 // commitment tx with four outputs untrimmed (minimum feerate)
6470                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6471                 chan.feerate_per_kw = 2195;
6472
6473                 test_commitment!("304402201a8c1b1f9671cd9e46c7323a104d7047cc48d3ee80d40d4512e0c72b8dc65666022066d7f9a2ce18c9eb22d2739ffcce05721c767f9b607622a31b6ea5793ddce403",
6474                                  "3044022044d592025b610c0d678f65032e87035cdfe89d1598c522cc32524ae8172417c30220749fef9d5b2ae8cdd91ece442ba8809bc891efedae2291e578475f97715d1767",
6475                                  "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", {
6476
6477                                   { 0,
6478                                   "3045022100e57b845066a06ee7c2cbfc29eabffe52daa9bf6f6de760066d04df9f9b250e0002202ffb197f0e6e0a77a75a9aff27014bd3de83b7f748d7efef986abe655e1dd50e",
6479                                   "3045022100ecc8c6529d0b2316d046f0f0757c1e1c25a636db168ec4f3aa1b9278df685dc0022067ae6b65e936f1337091f7b18a15935b608c5f2cdddb2f892ed0babfdd376d76",
6480                                   "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" },
6481
6482                                   { 1,
6483                                   "3045022100d193b7ecccad8057571620a0b1ffa6c48e9483311723b59cf536043b20bc51550220546d4bd37b3b101ecda14f6c907af46ec391abce1cd9c7ce22b1a62b534f2f2a",
6484                                   "3044022014d66f11f9cacf923807eba49542076c5fe5cccf252fb08fe98c78ef3ca6ab5402201b290dbe043cc512d9d78de074a5a129b8759bc6a6c546b190d120b690bd6e82",
6485                                   "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" }
6486                 } );
6487
6488                 // commitment tx with four outputs untrimmed (maximum feerate)
6489                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6490                 chan.feerate_per_kw = 3702;
6491
6492                 test_commitment!("304502210092a587aeb777f869e7ff0d7898ea619ee26a3dacd1f3672b945eea600be431100220077ee9eae3528d15251f2a52b607b189820e57a6ccfac8d1af502b132ee40169",
6493                                  "3045022100e5efb73c32d32da2d79702299b6317de6fb24a60476e3855926d78484dd1b3c802203557cb66a42c944ef06e00bcc4da35a5bcb2f185aab0f8e403e519e1d66aaf75",
6494                                  "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", {
6495
6496                                   { 0,
6497                                   "304402206fa54c11f98c3bae1e93df43fc7affeb05b476bf8060c03e29c377c69bc08e8b0220672701cce50d5c379ff45a5d2cfe48ac44973adb066ac32608e21221d869bb89",
6498                                   "304402206e36c683ebf2cb16bcef3d5439cf8b53cd97280a365ed8acd7abb85a8ba5f21c02206e8621edfc2a5766cbc96eb67fd501127ff163eb6b85518a39f7d4974aef126f",
6499                                   "020000000001018db483bff65c70ee71d8282aeec5a880e2e2b39e45772bda5460403095c62e3f0000000000000000000122020000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e050047304402206fa54c11f98c3bae1e93df43fc7affeb05b476bf8060c03e29c377c69bc08e8b0220672701cce50d5c379ff45a5d2cfe48ac44973adb066ac32608e21221d869bb890147304402206e36c683ebf2cb16bcef3d5439cf8b53cd97280a365ed8acd7abb85a8ba5f21c02206e8621edfc2a5766cbc96eb67fd501127ff163eb6b85518a39f7d4974aef126f01008576a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c820120876475527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae67a9148a486ff2e31d6158bf39e2608864d63fefd09d5b88ac6868f7010000" },
6500
6501                                   { 1,
6502                                   "3044022057649739b0eb74d541ead0dfdb3d4b2c15aa192720031044c3434c67812e5ca902201e5ede42d960ae551707f4a6b34b09393cf4dee2418507daa022e3550dbb5817",
6503                                   "304402207faad26678c8850e01b4a0696d60841f7305e1832b786110ee9075cb92ed14a30220516ef8ee5dfa80824ea28cbcec0dd95f8b847146257c16960db98507db15ffdc",
6504                                   "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" }
6505                 } );
6506
6507                 // commitment tx with three outputs untrimmed (minimum feerate)
6508                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6509                 chan.feerate_per_kw = 3703;
6510
6511                 test_commitment!("3045022100b495d239772a237ff2cf354b1b11be152fd852704cb184e7356d13f2fb1e5e430220723db5cdb9cbd6ead7bfd3deb419cf41053a932418cbb22a67b581f40bc1f13e",
6512                                  "304402201b736d1773a124c745586217a75bed5f66c05716fbe8c7db4fdb3c3069741cdd02205083f39c321c1bcadfc8d97e3c791a66273d936abac0c6a2fde2ed46019508e1",
6513                                  "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", {
6514
6515                                   { 0,
6516                                   "3045022100c34c61735f93f2e324cc873c3b248111ccf8f6db15d5969583757010d4ad2b4602207867bb919b2ddd6387873e425345c9b7fd18d1d66aba41f3607bc2896ef3c30a",
6517                                   "3045022100988c143e2110067117d2321bdd4bd16ca1734c98b29290d129384af0962b634e02206c1b02478878c5f547018b833986578f90c3e9be669fe5788ad0072a55acbb05",
6518                                   "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" }
6519                 } );
6520
6521                 // commitment tx with three outputs untrimmed (maximum feerate)
6522                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6523                 chan.feerate_per_kw = 4914;
6524
6525                 test_commitment!("3045022100b4b16d5f8cc9fc4c1aff48831e832a0d8990e133978a66e302c133550954a44d022073573ce127e2200d316f6b612803a5c0c97b8d20e1e44dbe2ac0dd2fb8c95244",
6526                                  "3045022100d72638bc6308b88bb6d45861aae83e5b9ff6e10986546e13bce769c70036e2620220320be7c6d66d22f30b9fcd52af66531505b1310ca3b848c19285b38d8a1a8c19",
6527                                  "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", {
6528
6529                                   { 0,
6530                                   "3045022100f43591c156038ba217756006bb3c55f7d113a325cdd7d9303c82115372858d68022016355b5aadf222bc8d12e426c75f4a03423917b2443a103eb2a498a3a2234374",
6531                                   "30440220585dee80fafa264beac535c3c0bb5838ac348b156fdc982f86adc08dfc9bfd250220130abb82f9f295cc9ef423dcfef772fde2acd85d9df48cc538981d26a10a9c10",
6532                                   "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" }
6533                 } );
6534
6535                 // commitment tx with two outputs untrimmed (minimum feerate)
6536                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6537                 chan.feerate_per_kw = 4915;
6538
6539                 test_commitment!("304402203a286936e74870ca1459c700c71202af0381910a6bfab687ef494ef1bc3e02c902202506c362d0e3bee15e802aa729bf378e051644648253513f1c085b264cc2a720",
6540                                  "30450221008a953551f4d67cb4df3037207fc082ddaf6be84d417b0bd14c80aab66f1b01a402207508796dc75034b2dee876fe01dc05a08b019f3e5d689ac8842ade2f1befccf5",
6541                                  "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", {});
6542
6543                 // commitment tx with two outputs untrimmed (maximum feerate)
6544                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6545                 chan.feerate_per_kw = 9651180;
6546
6547                 test_commitment!("304402200a8544eba1d216f5c5e530597665fa9bec56943c0f66d98fc3d028df52d84f7002201e45fa5c6bc3a506cc2553e7d1c0043a9811313fc39c954692c0d47cfce2bbd3",
6548                                  "3045022100e11b638c05c650c2f63a421d36ef8756c5ce82f2184278643520311cdf50aa200220259565fb9c8e4a87ccaf17f27a3b9ca4f20625754a0920d9c6c239d8156a11de",
6549                                  "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", {});
6550
6551                 // commitment tx with one output untrimmed (minimum feerate)
6552                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6553                 chan.feerate_per_kw = 9651181;
6554
6555                 test_commitment!("304402202ade0142008309eb376736575ad58d03e5b115499709c6db0b46e36ff394b492022037b63d78d66404d6504d4c4ac13be346f3d1802928a6d3ad95a6a944227161a2",
6556                                  "304402207e8d51e0c570a5868a78414f4e0cbfaed1106b171b9581542c30718ee4eb95ba02203af84194c97adf98898c9afe2f2ed4a7f8dba05a2dfab28ac9d9c604aa49a379",
6557                                  "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", {});
6558
6559                 // commitment tx with fee greater than funder amount
6560                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6561                 chan.feerate_per_kw = 9651936;
6562
6563                 test_commitment!("304402202ade0142008309eb376736575ad58d03e5b115499709c6db0b46e36ff394b492022037b63d78d66404d6504d4c4ac13be346f3d1802928a6d3ad95a6a944227161a2",
6564                                  "304402207e8d51e0c570a5868a78414f4e0cbfaed1106b171b9581542c30718ee4eb95ba02203af84194c97adf98898c9afe2f2ed4a7f8dba05a2dfab28ac9d9c604aa49a379",
6565                                  "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", {});
6566
6567                 // commitment tx with 3 htlc outputs, 2 offered having the same amount and preimage
6568                 chan.value_to_self_msat = 7_000_000_000 - 2_000_000;
6569                 chan.feerate_per_kw = 253;
6570                 chan.pending_inbound_htlcs.clear();
6571                 chan.pending_inbound_htlcs.push({
6572                         let mut out = InboundHTLCOutput{
6573                                 htlc_id: 1,
6574                                 amount_msat: 2000000,
6575                                 cltv_expiry: 501,
6576                                 payment_hash: PaymentHash([0; 32]),
6577                                 state: InboundHTLCState::Committed,
6578                         };
6579                         out.payment_hash.0 = Sha256::hash(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()).into_inner();
6580                         out
6581                 });
6582                 chan.pending_outbound_htlcs.clear();
6583                 chan.pending_outbound_htlcs.push({
6584                         let mut out = OutboundHTLCOutput{
6585                                 htlc_id: 6,
6586                                 amount_msat: 5000000,
6587                                 cltv_expiry: 506,
6588                                 payment_hash: PaymentHash([0; 32]),
6589                                 state: OutboundHTLCState::Committed,
6590                                 source: HTLCSource::dummy(),
6591                         };
6592                         out.payment_hash.0 = Sha256::hash(&hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()).into_inner();
6593                         out
6594                 });
6595                 chan.pending_outbound_htlcs.push({
6596                         let mut out = OutboundHTLCOutput{
6597                                 htlc_id: 5,
6598                                 amount_msat: 5000000,
6599                                 cltv_expiry: 505,
6600                                 payment_hash: PaymentHash([0; 32]),
6601                                 state: OutboundHTLCState::Committed,
6602                                 source: HTLCSource::dummy(),
6603                         };
6604                         out.payment_hash.0 = Sha256::hash(&hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()).into_inner();
6605                         out
6606                 });
6607
6608                 test_commitment!("30440220048705bec5288d28b3f29344b8d124853b1af423a568664d2c6f02c8ea886525022060f998a461052a2476b912db426ea2a06700953a241135c7957f2e79bc222df9",
6609                                  "3045022100c4f1d60b6fca9febc8b39de1a31e84c5f7c4b41c97239ef05f4350aa484c6b5e02200c5134ac8b20eb7a29d0dd4a501f6aa8fefb8489171f4cb408bd2a32324ab03f",
6610                                  "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", {
6611
6612                                   { 0,
6613                                   "304502210081cbb94121761d34c189cd4e6a281feea6f585060ad0ba2632e8d6b3c6bb8a6c02201007981bbd16539d63df2805b5568f1f5688cd2a885d04706f50db9b77ba13c6",
6614                                   "304502210090ed76aeb21b53236a598968abc66e2024691d07b62f53ddbeca8f93144af9c602205f873af5a0c10e62690e9aba09740550f194a9dc455ba4c1c23f6cde7704674c",
6615                                   "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" },
6616                                   { 1,
6617                                   "304402201d0f09d2bf7bc245a4f17980e1e9164290df16c70c6a2ff1592f5030d6108581022061e744a7dc151b36bf0aff7a4f1812ba90b8b03633bb979a270d19858fd960c5",
6618                                   "30450221009aef000d2e843a4202c1b1a2bf554abc9a7902bf49b2cb0759bc507456b7ebad02204e7c3d193ede2fd2b4cd6b39f51a920e581e35575e357e44d7b699c40ce61d39",
6619                                   "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" },
6620                                   { 2,
6621                                   "30440220010bf035d5823596e50dce2076a4d9f942d8d28031c9c428b901a02b6b8140de02203250e8e4a08bc5b4ecdca4d0eedf98223e02e3ac1c0206b3a7ffdb374aa21e5f",
6622                                   "30440220073de0067b88e425b3018b30366bfeda0ccb703118ccd3d02ead08c0f53511d002203fac50ac0e4cf8a3af0b4b1b12e801650591f748f8ddf1e089c160f10b69e511",
6623                                   "0200000000010189a326e23addc28323dbadcb4e71c2c17088b6e8fa184103e552f44075dddc3402000000000000000001e1120000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e05004730440220010bf035d5823596e50dce2076a4d9f942d8d28031c9c428b901a02b6b8140de02203250e8e4a08bc5b4ecdca4d0eedf98223e02e3ac1c0206b3a7ffdb374aa21e5f014730440220073de0067b88e425b3018b30366bfeda0ccb703118ccd3d02ead08c0f53511d002203fac50ac0e4cf8a3af0b4b1b12e801650591f748f8ddf1e089c160f10b69e51101008576a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c820120876475527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae67a9142002cc93ebefbb1b73f0af055dcc27a0b504ad7688ac6868fa010000" }
6624                 } );
6625         }
6626
6627         #[test]
6628         fn test_per_commitment_secret_gen() {
6629                 // Test vectors from BOLT 3 Appendix D:
6630
6631                 let mut seed = [0; 32];
6632                 seed[0..32].clone_from_slice(&hex::decode("0000000000000000000000000000000000000000000000000000000000000000").unwrap());
6633                 assert_eq!(chan_utils::build_commitment_secret(&seed, 281474976710655),
6634                            hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap()[..]);
6635
6636                 seed[0..32].clone_from_slice(&hex::decode("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF").unwrap());
6637                 assert_eq!(chan_utils::build_commitment_secret(&seed, 281474976710655),
6638                            hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap()[..]);
6639
6640                 assert_eq!(chan_utils::build_commitment_secret(&seed, 0xaaaaaaaaaaa),
6641                            hex::decode("56f4008fb007ca9acf0e15b054d5c9fd12ee06cea347914ddbaed70d1c13a528").unwrap()[..]);
6642
6643                 assert_eq!(chan_utils::build_commitment_secret(&seed, 0x555555555555),
6644                            hex::decode("9015daaeb06dba4ccc05b91b2f73bd54405f2be9f217fbacd3c5ac2e62327d31").unwrap()[..]);
6645
6646                 seed[0..32].clone_from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap());
6647                 assert_eq!(chan_utils::build_commitment_secret(&seed, 1),
6648                            hex::decode("915c75942a26bb3a433a8ce2cb0427c29ec6c1775cfc78328b57f6ba7bfeaa9c").unwrap()[..]);
6649         }
6650
6651         #[test]
6652         fn test_key_derivation() {
6653                 // Test vectors from BOLT 3 Appendix E:
6654                 let secp_ctx = Secp256k1::new();
6655
6656                 let base_secret = SecretKey::from_slice(&hex::decode("000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f").unwrap()[..]).unwrap();
6657                 let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
6658
6659                 let base_point = PublicKey::from_secret_key(&secp_ctx, &base_secret);
6660                 assert_eq!(base_point.serialize()[..], hex::decode("036d6caac248af96f6afa7f904f550253a0f3ef3f5aa2fe6838a95b216691468e2").unwrap()[..]);
6661
6662                 let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
6663                 assert_eq!(per_commitment_point.serialize()[..], hex::decode("025f7117a78150fe2ef97db7cfc83bd57b2e2c0d0dd25eaf467a4a1c2a45ce1486").unwrap()[..]);
6664
6665                 assert_eq!(chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &base_point).unwrap().serialize()[..],
6666                                 hex::decode("0235f2dbfaa89b57ec7b055afe29849ef7ddfeb1cefdb9ebdc43f5494984db29e5").unwrap()[..]);
6667
6668                 assert_eq!(chan_utils::derive_private_key(&secp_ctx, &per_commitment_point, &base_secret).unwrap(),
6669                                 SecretKey::from_slice(&hex::decode("cbced912d3b21bf196a766651e436aff192362621ce317704ea2f75d87e7be0f").unwrap()[..]).unwrap());
6670
6671                 assert_eq!(chan_utils::derive_public_revocation_key(&secp_ctx, &per_commitment_point, &base_point).unwrap().serialize()[..],
6672                                 hex::decode("02916e326636d19c33f13e8c0c3a03dd157f332f3e99c317c141dd865eb01f8ff0").unwrap()[..]);
6673
6674                 assert_eq!(chan_utils::derive_private_revocation_key(&secp_ctx, &per_commitment_secret, &base_secret).unwrap(),
6675                                 SecretKey::from_slice(&hex::decode("d09ffff62ddb2297ab000cc85bcb4283fdeb6aa052affbc9dddcf33b61078110").unwrap()[..]).unwrap());
6676         }
6677 }