Automatically close channels that go unfunded for 2016 blocks
[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(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 }
297
298 /// Used when calculating whether we or the remote can afford an additional HTLC.
299 struct HTLCCandidate {
300         amount_msat: u64,
301         origin: HTLCInitiator,
302 }
303
304 impl HTLCCandidate {
305         fn new(amount_msat: u64, origin: HTLCInitiator) -> Self {
306                 Self {
307                         amount_msat,
308                         origin,
309                 }
310         }
311 }
312
313 /// A return value enum for get_update_fulfill_htlc. See UpdateFulfillCommitFetch variants for
314 /// description
315 enum UpdateFulfillFetch {
316         NewClaim {
317                 monitor_update: ChannelMonitorUpdate,
318                 htlc_value_msat: u64,
319                 msg: Option<msgs::UpdateFulfillHTLC>,
320         },
321         DuplicateClaim {},
322 }
323
324 /// The return type of get_update_fulfill_htlc_and_commit.
325 pub enum UpdateFulfillCommitFetch {
326         /// Indicates the HTLC fulfill is new, and either generated an update_fulfill message, placed
327         /// it in the holding cell, or re-generated the update_fulfill message after the same claim was
328         /// previously placed in the holding cell (and has since been removed).
329         NewClaim {
330                 /// The ChannelMonitorUpdate which places the new payment preimage in the channel monitor
331                 monitor_update: ChannelMonitorUpdate,
332                 /// The value of the HTLC which was claimed, in msat.
333                 htlc_value_msat: u64,
334                 /// The update_fulfill message and commitment_signed message (if the claim was not placed
335                 /// in the holding cell).
336                 msgs: Option<(msgs::UpdateFulfillHTLC, msgs::CommitmentSigned)>,
337         },
338         /// Indicates the HTLC fulfill is duplicative and already existed either in the holding cell
339         /// or has been forgotten (presumably previously claimed).
340         DuplicateClaim {},
341 }
342
343 /// The return value of `revoke_and_ack` on success, primarily updates to other channels or HTLC
344 /// state.
345 pub(super) struct RAAUpdates {
346         pub commitment_update: Option<msgs::CommitmentUpdate>,
347         pub accepted_htlcs: Vec<(PendingHTLCInfo, u64)>,
348         pub failed_htlcs: Vec<(HTLCSource, PaymentHash, HTLCFailReason)>,
349         pub finalized_claimed_htlcs: Vec<HTLCSource>,
350         pub monitor_update: ChannelMonitorUpdate,
351         pub holding_cell_failed_htlcs: Vec<(HTLCSource, PaymentHash)>,
352 }
353
354 /// The return value of `monitor_updating_restored`
355 pub(super) struct MonitorRestoreUpdates {
356         pub raa: Option<msgs::RevokeAndACK>,
357         pub commitment_update: Option<msgs::CommitmentUpdate>,
358         pub order: RAACommitmentOrder,
359         pub accepted_htlcs: Vec<(PendingHTLCInfo, u64)>,
360         pub failed_htlcs: Vec<(HTLCSource, PaymentHash, HTLCFailReason)>,
361         pub finalized_claimed_htlcs: Vec<HTLCSource>,
362         pub funding_broadcastable: Option<Transaction>,
363         pub funding_locked: Option<msgs::FundingLocked>,
364 }
365
366 /// If the majority of the channels funds are to the fundee and the initiator holds only just
367 /// enough funds to cover their reserve value, channels are at risk of getting "stuck". Because the
368 /// initiator controls the feerate, if they then go to increase the channel fee, they may have no
369 /// balance but the fundee is unable to send a payment as the increase in fee more than drains
370 /// their reserve value. Thus, neither side can send a new HTLC and the channel becomes useless.
371 /// Thus, before sending an HTLC when we are the initiator, we check that the feerate can increase
372 /// by this multiple without hitting this case, before sending.
373 /// This multiple is effectively the maximum feerate "jump" we expect until more HTLCs flow over
374 /// the channel. Sadly, there isn't really a good number for this - if we expect to have no new
375 /// HTLCs for days we may need this to suffice for feerate increases across days, but that may
376 /// leave the channel less usable as we hold a bigger reserve.
377 #[cfg(fuzzing)]
378 pub const FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE: u64 = 2;
379 #[cfg(not(fuzzing))]
380 const FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE: u64 = 2;
381
382 /// If we fail to see a funding transaction confirmed on-chain within this many blocks after the
383 /// channel creation on an inbound channel, we simply force-close and move on.
384 /// This constant is the one suggested in BOLT 2.
385 pub(crate) const FUNDING_CONF_DEADLINE_BLOCKS: u32 = 2016;
386
387 // TODO: We should refactor this to be an Inbound/OutboundChannel until initial setup handshaking
388 // has been completed, and then turn into a Channel to get compiler-time enforcement of things like
389 // calling channel_id() before we're set up or things like get_outbound_funding_signed on an
390 // inbound channel.
391 //
392 // Holder designates channel data owned for the benefice of the user client.
393 // Counterparty designates channel data owned by the another channel participant entity.
394 pub(super) struct Channel<Signer: Sign> {
395         #[cfg(any(test, feature = "_test_utils"))]
396         pub(crate) config: ChannelConfig,
397         #[cfg(not(any(test, feature = "_test_utils")))]
398         config: ChannelConfig,
399
400         user_id: u64,
401
402         channel_id: [u8; 32],
403         channel_state: u32,
404         secp_ctx: Secp256k1<secp256k1::All>,
405         channel_value_satoshis: u64,
406
407         latest_monitor_update_id: u64,
408
409         holder_signer: Signer,
410         shutdown_scriptpubkey: Option<ShutdownScript>,
411         destination_script: Script,
412
413         // Our commitment numbers start at 2^48-1 and count down, whereas the ones used in transaction
414         // generation start at 0 and count up...this simplifies some parts of implementation at the
415         // cost of others, but should really just be changed.
416
417         cur_holder_commitment_transaction_number: u64,
418         cur_counterparty_commitment_transaction_number: u64,
419         value_to_self_msat: u64, // Excluding all pending_htlcs, excluding fees
420         pending_inbound_htlcs: Vec<InboundHTLCOutput>,
421         pending_outbound_htlcs: Vec<OutboundHTLCOutput>,
422         holding_cell_htlc_updates: Vec<HTLCUpdateAwaitingACK>,
423
424         /// When resending CS/RAA messages on channel monitor restoration or on reconnect, we always
425         /// need to ensure we resend them in the order we originally generated them. Note that because
426         /// there can only ever be one in-flight CS and/or one in-flight RAA at any time, it is
427         /// sufficient to simply set this to the opposite of any message we are generating as we
428         /// generate it. ie when we generate a CS, we set this to RAAFirst as, if there is a pending
429         /// in-flight RAA to resend, it will have been the first thing we generated, and thus we should
430         /// send it first.
431         resend_order: RAACommitmentOrder,
432
433         monitor_pending_funding_locked: bool,
434         monitor_pending_revoke_and_ack: bool,
435         monitor_pending_commitment_signed: bool,
436         monitor_pending_forwards: Vec<(PendingHTLCInfo, u64)>,
437         monitor_pending_failures: Vec<(HTLCSource, PaymentHash, HTLCFailReason)>,
438         monitor_pending_finalized_fulfills: Vec<HTLCSource>,
439
440         // pending_update_fee is filled when sending and receiving update_fee.
441         //
442         // Because it follows the same commitment flow as HTLCs, `FeeUpdateState` is either `Outbound`
443         // or matches a subset of the `InboundHTLCOutput` variants. It is then updated/used when
444         // generating new commitment transactions with exactly the same criteria as inbound/outbound
445         // HTLCs with similar state.
446         pending_update_fee: Option<(u32, FeeUpdateState)>,
447         // If a `send_update_fee()` call is made with ChannelState::AwaitingRemoteRevoke set, we place
448         // it here instead of `pending_update_fee` in the same way as we place outbound HTLC updates in
449         // `holding_cell_htlc_updates` instead of `pending_outbound_htlcs`. It is released into
450         // `pending_update_fee` with the same criteria as outbound HTLC updates but can be updated by
451         // further `send_update_fee` calls, dropping the previous holding cell update entirely.
452         holding_cell_update_fee: Option<u32>,
453         next_holder_htlc_id: u64,
454         next_counterparty_htlc_id: u64,
455         update_time_counter: u32,
456         feerate_per_kw: u32,
457
458         #[cfg(debug_assertions)]
459         /// Max to_local and to_remote outputs in a locally-generated commitment transaction
460         holder_max_commitment_tx_output: Mutex<(u64, u64)>,
461         #[cfg(debug_assertions)]
462         /// Max to_local and to_remote outputs in a remote-generated commitment transaction
463         counterparty_max_commitment_tx_output: Mutex<(u64, u64)>,
464
465         last_sent_closing_fee: Option<(u64, Signature)>, // (fee, holder_sig)
466         target_closing_feerate_sats_per_kw: Option<u32>,
467
468         /// If our counterparty sent us a closing_signed while we were waiting for a `ChannelMonitor`
469         /// update, we need to delay processing it until later. We do that here by simply storing the
470         /// closing_signed message and handling it in `maybe_propose_closing_signed`.
471         pending_counterparty_closing_signed: Option<msgs::ClosingSigned>,
472
473         /// The minimum and maximum absolute fee, in satoshis, we are willing to place on the closing
474         /// transaction. These are set once we reach `closing_negotiation_ready`.
475         #[cfg(test)]
476         pub(crate) closing_fee_limits: Option<(u64, u64)>,
477         #[cfg(not(test))]
478         closing_fee_limits: Option<(u64, u64)>,
479
480         /// The hash of the block in which the funding transaction was included.
481         funding_tx_confirmed_in: Option<BlockHash>,
482         funding_tx_confirmation_height: u32,
483         short_channel_id: Option<u64>,
484         /// Either the height at which this channel was created or the height at which it was last
485         /// serialized if it was serialized by versions prior to 0.0.103.
486         /// We use this to close if funding is never broadcasted.
487         channel_creation_height: u32,
488
489         counterparty_dust_limit_satoshis: u64,
490         #[cfg(test)]
491         pub(super) holder_dust_limit_satoshis: u64,
492         #[cfg(not(test))]
493         holder_dust_limit_satoshis: u64,
494         #[cfg(test)]
495         pub(super) counterparty_max_htlc_value_in_flight_msat: u64,
496         #[cfg(not(test))]
497         counterparty_max_htlc_value_in_flight_msat: u64,
498         //get_holder_max_htlc_value_in_flight_msat(): u64,
499         /// minimum channel reserve for self to maintain - set by them.
500         counterparty_selected_channel_reserve_satoshis: Option<u64>,
501         // get_holder_selected_channel_reserve_satoshis(channel_value_sats: u64): u64
502         counterparty_htlc_minimum_msat: u64,
503         holder_htlc_minimum_msat: u64,
504         #[cfg(test)]
505         pub counterparty_max_accepted_htlcs: u16,
506         #[cfg(not(test))]
507         counterparty_max_accepted_htlcs: u16,
508         //implied by OUR_MAX_HTLCS: max_accepted_htlcs: u16,
509         minimum_depth: Option<u32>,
510
511         counterparty_forwarding_info: Option<CounterpartyForwardingInfo>,
512
513         pub(crate) channel_transaction_parameters: ChannelTransactionParameters,
514         funding_transaction: Option<Transaction>,
515
516         counterparty_cur_commitment_point: Option<PublicKey>,
517         counterparty_prev_commitment_point: Option<PublicKey>,
518         counterparty_node_id: PublicKey,
519
520         counterparty_shutdown_scriptpubkey: Option<Script>,
521
522         commitment_secrets: CounterpartyCommitmentSecrets,
523
524         channel_update_status: ChannelUpdateStatus,
525         /// Once we reach `closing_negotiation_ready`, we set this, indicating if closing_signed does
526         /// not complete within a single timer tick (one minute), we should force-close the channel.
527         /// This prevents us from keeping unusable channels around forever if our counterparty wishes
528         /// to DoS us.
529         /// Note that this field is reset to false on deserialization to give us a chance to connect to
530         /// our peer and start the closing_signed negotiation fresh.
531         closing_signed_in_flight: bool,
532
533         /// Our counterparty's channel_announcement signatures provided in announcement_signatures.
534         /// This can be used to rebroadcast the channel_announcement message later.
535         announcement_sigs: Option<(Signature, Signature)>,
536
537         // We save these values so we can make sure `next_local_commit_tx_fee_msat` and
538         // `next_remote_commit_tx_fee_msat` properly predict what the next commitment transaction fee will
539         // be, by comparing the cached values to the fee of the tranaction generated by
540         // `build_commitment_transaction`.
541         #[cfg(any(test, feature = "fuzztarget"))]
542         next_local_commitment_tx_fee_info_cached: Mutex<Option<CommitmentTxInfoCached>>,
543         #[cfg(any(test, feature = "fuzztarget"))]
544         next_remote_commitment_tx_fee_info_cached: Mutex<Option<CommitmentTxInfoCached>>,
545
546         /// lnd has a long-standing bug where, upon reconnection, if the channel is not yet confirmed
547         /// they will not send a channel_reestablish until the channel locks in. Then, they will send a
548         /// funding_locked *before* sending the channel_reestablish (which is clearly a violation of
549         /// the BOLT specs). We copy c-lightning's workaround here and simply store the funding_locked
550         /// message until we receive a channel_reestablish.
551         ///
552         /// See-also <https://github.com/lightningnetwork/lnd/issues/4006>
553         pub workaround_lnd_bug_4006: Option<msgs::FundingLocked>,
554
555         #[cfg(any(test, feature = "fuzztarget"))]
556         // When we receive an HTLC fulfill on an outbound path, we may immediately fulfill the
557         // corresponding HTLC on the inbound path. If, then, the outbound path channel is
558         // disconnected and reconnected (before we've exchange commitment_signed and revoke_and_ack
559         // messages), they may re-broadcast their update_fulfill_htlc, causing a duplicate claim. This
560         // is fine, but as a sanity check in our failure to generate the second claim, we check here
561         // that the original was a claim, and that we aren't now trying to fulfill a failed HTLC.
562         historical_inbound_htlc_fulfills: HashSet<u64>,
563
564         /// This channel's type, as negotiated during channel open
565         channel_type: ChannelTypeFeatures,
566 }
567
568 #[cfg(any(test, feature = "fuzztarget"))]
569 struct CommitmentTxInfoCached {
570         fee: u64,
571         total_pending_htlcs: usize,
572         next_holder_htlc_id: u64,
573         next_counterparty_htlc_id: u64,
574         feerate: u32,
575 }
576
577 pub const OUR_MAX_HTLCS: u16 = 50; //TODO
578
579 #[cfg(not(test))]
580 const COMMITMENT_TX_BASE_WEIGHT: u64 = 724;
581 #[cfg(test)]
582 pub const COMMITMENT_TX_BASE_WEIGHT: u64 = 724;
583 #[cfg(not(test))]
584 const COMMITMENT_TX_WEIGHT_PER_HTLC: u64 = 172;
585 #[cfg(test)]
586 pub const COMMITMENT_TX_WEIGHT_PER_HTLC: u64 = 172;
587
588 pub const ANCHOR_OUTPUT_VALUE_SATOSHI: u64 = 330;
589
590 /// Maximum `funding_satoshis` value, according to the BOLT #2 specification
591 /// it's 2^24.
592 pub const MAX_FUNDING_SATOSHIS: u64 = 1 << 24;
593
594 /// The maximum network dust limit for standard script formats. This currently represents the
595 /// minimum output value for a P2SH output before Bitcoin Core 22 considers the entire
596 /// transaction non-standard and thus refuses to relay it.
597 /// We also use this as the maximum counterparty `dust_limit_satoshis` allowed, given many
598 /// implementations use this value for their dust limit today.
599 pub const MAX_STD_OUTPUT_DUST_LIMIT_SATOSHIS: u64 = 546;
600
601 /// The maximum channel dust limit we will accept from our counterparty.
602 pub const MAX_CHAN_DUST_LIMIT_SATOSHIS: u64 = MAX_STD_OUTPUT_DUST_LIMIT_SATOSHIS;
603
604 /// The dust limit is used for both the commitment transaction outputs as well as the closing
605 /// transactions. For cooperative closing transactions, we require segwit outputs, though accept
606 /// *any* segwit scripts, which are allowed to be up to 42 bytes in length.
607 /// In order to avoid having to concern ourselves with standardness during the closing process, we
608 /// simply require our counterparty to use a dust limit which will leave any segwit output
609 /// standard.
610 /// See https://github.com/lightningnetwork/lightning-rfc/issues/905 for more details.
611 pub const MIN_CHAN_DUST_LIMIT_SATOSHIS: u64 = 354;
612
613 /// Used to return a simple Error back to ChannelManager. Will get converted to a
614 /// msgs::ErrorAction::SendErrorMessage or msgs::ErrorAction::IgnoreError as appropriate with our
615 /// channel_id in ChannelManager.
616 pub(super) enum ChannelError {
617         Ignore(String),
618         Warn(String),
619         Close(String),
620         CloseDelayBroadcast(String),
621 }
622
623 impl fmt::Debug for ChannelError {
624         fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
625                 match self {
626                         &ChannelError::Ignore(ref e) => write!(f, "Ignore : {}", e),
627                         &ChannelError::Warn(ref e) => write!(f, "Warn : {}", e),
628                         &ChannelError::Close(ref e) => write!(f, "Close : {}", e),
629                         &ChannelError::CloseDelayBroadcast(ref e) => write!(f, "CloseDelayBroadcast : {}", e)
630                 }
631         }
632 }
633
634 macro_rules! secp_check {
635         ($res: expr, $err: expr) => {
636                 match $res {
637                         Ok(thing) => thing,
638                         Err(_) => return Err(ChannelError::Close($err)),
639                 }
640         };
641 }
642
643 impl<Signer: Sign> Channel<Signer> {
644         // Convert constants + channel value to limits:
645         fn get_holder_max_htlc_value_in_flight_msat(channel_value_satoshis: u64) -> u64 {
646                 channel_value_satoshis * 1000 / 10 //TODO
647         }
648
649         /// Returns a minimum channel reserve value the remote needs to maintain,
650         /// required by us.
651         ///
652         /// Guaranteed to return a value no larger than channel_value_satoshis
653         pub(crate) fn get_holder_selected_channel_reserve_satoshis(channel_value_satoshis: u64) -> u64 {
654                 let (q, _) = channel_value_satoshis.overflowing_div(100);
655                 cmp::min(channel_value_satoshis, cmp::max(q, 1000)) //TODO
656         }
657
658         // Constructors:
659         pub fn new_outbound<K: Deref, F: Deref>(
660                 fee_estimator: &F, keys_provider: &K, counterparty_node_id: PublicKey, their_features: &InitFeatures,
661                 channel_value_satoshis: u64, push_msat: u64, user_id: u64, config: &UserConfig, current_chain_height: u32
662         ) -> Result<Channel<Signer>, APIError>
663         where K::Target: KeysInterface<Signer = Signer>,
664               F::Target: FeeEstimator,
665         {
666                 let holder_selected_contest_delay = config.own_channel_config.our_to_self_delay;
667                 let holder_signer = keys_provider.get_channel_signer(false, channel_value_satoshis);
668                 let pubkeys = holder_signer.pubkeys().clone();
669
670                 if channel_value_satoshis >= MAX_FUNDING_SATOSHIS {
671                         return Err(APIError::APIMisuseError{err: format!("funding_value must be smaller than {}, it was {}", MAX_FUNDING_SATOSHIS, channel_value_satoshis)});
672                 }
673                 let channel_value_msat = channel_value_satoshis * 1000;
674                 if push_msat > channel_value_msat {
675                         return Err(APIError::APIMisuseError { err: format!("Push value ({}) was larger than channel_value ({})", push_msat, channel_value_msat) });
676                 }
677                 if holder_selected_contest_delay < BREAKDOWN_TIMEOUT {
678                         return Err(APIError::APIMisuseError {err: format!("Configured with an unreasonable our_to_self_delay ({}) putting user funds at risks", holder_selected_contest_delay)});
679                 }
680                 let holder_selected_channel_reserve_satoshis = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(channel_value_satoshis);
681                 if holder_selected_channel_reserve_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
682                         return Err(APIError::APIMisuseError { err: format!("Holder selected channel  reserve below implemention limit dust_limit_satoshis {}", holder_selected_channel_reserve_satoshis) });
683                 }
684
685                 let feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
686
687                 let mut secp_ctx = Secp256k1::new();
688                 secp_ctx.seeded_randomize(&keys_provider.get_secure_random_bytes());
689
690                 let shutdown_scriptpubkey = if config.channel_options.commit_upfront_shutdown_pubkey {
691                         Some(keys_provider.get_shutdown_scriptpubkey())
692                 } else { None };
693
694                 if let Some(shutdown_scriptpubkey) = &shutdown_scriptpubkey {
695                         if !shutdown_scriptpubkey.is_compatible(&their_features) {
696                                 return Err(APIError::IncompatibleShutdownScript { script: shutdown_scriptpubkey.clone() });
697                         }
698                 }
699
700                 Ok(Channel {
701                         user_id,
702                         config: config.channel_options.clone(),
703
704                         channel_id: keys_provider.get_secure_random_bytes(),
705                         channel_state: ChannelState::OurInitSent as u32,
706                         secp_ctx,
707                         channel_value_satoshis,
708
709                         latest_monitor_update_id: 0,
710
711                         holder_signer,
712                         shutdown_scriptpubkey,
713                         destination_script: keys_provider.get_destination_script(),
714
715                         cur_holder_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
716                         cur_counterparty_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
717                         value_to_self_msat: channel_value_satoshis * 1000 - push_msat,
718
719                         pending_inbound_htlcs: Vec::new(),
720                         pending_outbound_htlcs: Vec::new(),
721                         holding_cell_htlc_updates: Vec::new(),
722                         pending_update_fee: None,
723                         holding_cell_update_fee: None,
724                         next_holder_htlc_id: 0,
725                         next_counterparty_htlc_id: 0,
726                         update_time_counter: 1,
727
728                         resend_order: RAACommitmentOrder::CommitmentFirst,
729
730                         monitor_pending_funding_locked: false,
731                         monitor_pending_revoke_and_ack: false,
732                         monitor_pending_commitment_signed: false,
733                         monitor_pending_forwards: Vec::new(),
734                         monitor_pending_failures: Vec::new(),
735                         monitor_pending_finalized_fulfills: Vec::new(),
736
737                         #[cfg(debug_assertions)]
738                         holder_max_commitment_tx_output: Mutex::new((channel_value_satoshis * 1000 - push_msat, push_msat)),
739                         #[cfg(debug_assertions)]
740                         counterparty_max_commitment_tx_output: Mutex::new((channel_value_satoshis * 1000 - push_msat, push_msat)),
741
742                         last_sent_closing_fee: None,
743                         pending_counterparty_closing_signed: None,
744                         closing_fee_limits: None,
745                         target_closing_feerate_sats_per_kw: None,
746
747                         funding_tx_confirmed_in: None,
748                         funding_tx_confirmation_height: 0,
749                         short_channel_id: None,
750                         channel_creation_height: current_chain_height,
751
752                         feerate_per_kw: feerate,
753                         counterparty_dust_limit_satoshis: 0,
754                         holder_dust_limit_satoshis: MIN_CHAN_DUST_LIMIT_SATOSHIS,
755                         counterparty_max_htlc_value_in_flight_msat: 0,
756                         counterparty_selected_channel_reserve_satoshis: None, // Filled in in accept_channel
757                         counterparty_htlc_minimum_msat: 0,
758                         holder_htlc_minimum_msat: if config.own_channel_config.our_htlc_minimum_msat == 0 { 1 } else { config.own_channel_config.our_htlc_minimum_msat },
759                         counterparty_max_accepted_htlcs: 0,
760                         minimum_depth: None, // Filled in in accept_channel
761
762                         counterparty_forwarding_info: None,
763
764                         channel_transaction_parameters: ChannelTransactionParameters {
765                                 holder_pubkeys: pubkeys,
766                                 holder_selected_contest_delay: config.own_channel_config.our_to_self_delay,
767                                 is_outbound_from_holder: true,
768                                 counterparty_parameters: None,
769                                 funding_outpoint: None
770                         },
771                         funding_transaction: None,
772
773                         counterparty_cur_commitment_point: None,
774                         counterparty_prev_commitment_point: None,
775                         counterparty_node_id,
776
777                         counterparty_shutdown_scriptpubkey: None,
778
779                         commitment_secrets: CounterpartyCommitmentSecrets::new(),
780
781                         channel_update_status: ChannelUpdateStatus::Enabled,
782                         closing_signed_in_flight: false,
783
784                         announcement_sigs: None,
785
786                         #[cfg(any(test, feature = "fuzztarget"))]
787                         next_local_commitment_tx_fee_info_cached: Mutex::new(None),
788                         #[cfg(any(test, feature = "fuzztarget"))]
789                         next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
790
791                         workaround_lnd_bug_4006: None,
792
793                         #[cfg(any(test, feature = "fuzztarget"))]
794                         historical_inbound_htlc_fulfills: HashSet::new(),
795
796                         // We currently only actually support one channel type, so don't retry with new types
797                         // on error messages. When we support more we'll need fallback support (assuming we
798                         // want to support old types).
799                         channel_type: ChannelTypeFeatures::only_static_remote_key(),
800                 })
801         }
802
803         fn check_remote_fee<F: Deref>(fee_estimator: &F, feerate_per_kw: u32) -> Result<(), ChannelError>
804                 where F::Target: FeeEstimator
805         {
806                 let lower_limit = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
807                 if feerate_per_kw < lower_limit {
808                         return Err(ChannelError::Close(format!("Peer's feerate much too low. Actual: {}. Our expected lower limit: {}", feerate_per_kw, lower_limit)));
809                 }
810                 // We only bound the fee updates on the upper side to prevent completely absurd feerates,
811                 // always accepting up to 25 sat/vByte or 10x our fee estimator's "High Priority" fee.
812                 // We generally don't care too much if they set the feerate to something very high, but it
813                 // could result in the channel being useless due to everything being dust.
814                 let upper_limit = cmp::max(250 * 25,
815                         fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::HighPriority) as u64 * 10);
816                 if feerate_per_kw as u64 > upper_limit {
817                         return Err(ChannelError::Close(format!("Peer's feerate much too high. Actual: {}. Our expected upper limit: {}", feerate_per_kw, upper_limit)));
818                 }
819                 Ok(())
820         }
821
822         /// Creates a new channel from a remote sides' request for one.
823         /// Assumes chain_hash has already been checked and corresponds with what we expect!
824         pub fn new_from_req<K: Deref, F: Deref>(
825                 fee_estimator: &F, keys_provider: &K, counterparty_node_id: PublicKey, their_features: &InitFeatures,
826                 msg: &msgs::OpenChannel, user_id: u64, config: &UserConfig, current_chain_height: u32
827         ) -> Result<Channel<Signer>, ChannelError>
828                 where K::Target: KeysInterface<Signer = Signer>,
829           F::Target: FeeEstimator
830         {
831                 // First check the channel type is known, failing before we do anything else if we don't
832                 // support this channel type.
833                 let channel_type = if let Some(channel_type) = &msg.channel_type {
834                         if channel_type.supports_any_optional_bits() {
835                                 return Err(ChannelError::Close("Channel Type field contained optional bits - this is not allowed".to_owned()));
836                         }
837                         if *channel_type != ChannelTypeFeatures::only_static_remote_key() {
838                                 return Err(ChannelError::Close("Channel Type was not understood".to_owned()));
839                         }
840                         channel_type.clone()
841                 } else {
842                         ChannelTypeFeatures::from_counterparty_init(&their_features)
843                 };
844                 if !channel_type.supports_static_remote_key() {
845                         return Err(ChannelError::Close("Channel Type was not understood - we require static remote key".to_owned()));
846                 }
847
848                 let holder_signer = keys_provider.get_channel_signer(true, msg.funding_satoshis);
849                 let pubkeys = holder_signer.pubkeys().clone();
850                 let counterparty_pubkeys = ChannelPublicKeys {
851                         funding_pubkey: msg.funding_pubkey,
852                         revocation_basepoint: msg.revocation_basepoint,
853                         payment_point: msg.payment_point,
854                         delayed_payment_basepoint: msg.delayed_payment_basepoint,
855                         htlc_basepoint: msg.htlc_basepoint
856                 };
857                 let mut local_config = (*config).channel_options.clone();
858
859                 if config.own_channel_config.our_to_self_delay < BREAKDOWN_TIMEOUT {
860                         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)));
861                 }
862
863                 // Check sanity of message fields:
864                 if msg.funding_satoshis >= MAX_FUNDING_SATOSHIS {
865                         return Err(ChannelError::Close(format!("Funding must be smaller than {}. It was {}", MAX_FUNDING_SATOSHIS, msg.funding_satoshis)));
866                 }
867                 if msg.channel_reserve_satoshis > msg.funding_satoshis {
868                         return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must be not greater than funding_satoshis: {}", msg.channel_reserve_satoshis, msg.funding_satoshis)));
869                 }
870                 let funding_value = (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000;
871                 if msg.push_msat > funding_value {
872                         return Err(ChannelError::Close(format!("push_msat {} was larger than funding value {}", msg.push_msat, funding_value)));
873                 }
874                 if msg.dust_limit_satoshis > msg.funding_satoshis {
875                         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)));
876                 }
877                 if msg.dust_limit_satoshis > msg.channel_reserve_satoshis {
878                         return Err(ChannelError::Close(format!("Bogus; channel reserve ({}) is less than dust limit ({})", msg.channel_reserve_satoshis, msg.dust_limit_satoshis)));
879                 }
880                 let full_channel_value_msat = (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000;
881                 if msg.htlc_minimum_msat >= full_channel_value_msat {
882                         return Err(ChannelError::Close(format!("Minimum htlc value ({}) was larger than full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat)));
883                 }
884                 Channel::<Signer>::check_remote_fee(fee_estimator, msg.feerate_per_kw)?;
885
886                 let max_counterparty_selected_contest_delay = u16::min(config.peer_channel_config_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
887                 if msg.to_self_delay > max_counterparty_selected_contest_delay {
888                         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)));
889                 }
890                 if msg.max_accepted_htlcs < 1 {
891                         return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel".to_owned()));
892                 }
893                 if msg.max_accepted_htlcs > MAX_HTLCS {
894                         return Err(ChannelError::Close(format!("max_accepted_htlcs was {}. It must not be larger than {}", msg.max_accepted_htlcs, MAX_HTLCS)));
895                 }
896
897                 // Now check against optional parameters as set by config...
898                 if msg.funding_satoshis < config.peer_channel_config_limits.min_funding_satoshis {
899                         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)));
900                 }
901                 if msg.htlc_minimum_msat > config.peer_channel_config_limits.max_htlc_minimum_msat {
902                         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)));
903                 }
904                 if msg.max_htlc_value_in_flight_msat < config.peer_channel_config_limits.min_max_htlc_value_in_flight_msat {
905                         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)));
906                 }
907                 if msg.channel_reserve_satoshis > config.peer_channel_config_limits.max_channel_reserve_satoshis {
908                         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)));
909                 }
910                 if msg.max_accepted_htlcs < config.peer_channel_config_limits.min_max_accepted_htlcs {
911                         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)));
912                 }
913                 if msg.dust_limit_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
914                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the implementation limit ({})", msg.dust_limit_satoshis, MIN_CHAN_DUST_LIMIT_SATOSHIS)));
915                 }
916                 if msg.dust_limit_satoshis >  MAX_CHAN_DUST_LIMIT_SATOSHIS {
917                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the implementation limit ({})", msg.dust_limit_satoshis, MAX_CHAN_DUST_LIMIT_SATOSHIS)));
918                 }
919
920                 // Convert things into internal flags and prep our state:
921
922                 let announce = if (msg.channel_flags & 1) == 1 { true } else { false };
923                 if config.peer_channel_config_limits.force_announced_channel_preference {
924                         if local_config.announced_channel != announce {
925                                 return Err(ChannelError::Close("Peer tried to open channel but their announcement preference is different from ours".to_owned()));
926                         }
927                 }
928                 // we either accept their preference or the preferences match
929                 local_config.announced_channel = announce;
930
931                 let background_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
932
933                 let holder_selected_channel_reserve_satoshis = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(msg.funding_satoshis);
934                 if holder_selected_channel_reserve_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
935                         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)));
936                 }
937                 if msg.channel_reserve_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
938                         return Err(ChannelError::Close(format!("channel_reserve_satoshis ({}) is smaller than our dust limit ({})", msg.channel_reserve_satoshis, MIN_CHAN_DUST_LIMIT_SATOSHIS)));
939                 }
940                 if holder_selected_channel_reserve_satoshis < msg.dust_limit_satoshis {
941                         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)));
942                 }
943
944                 // check if the funder's amount for the initial commitment tx is sufficient
945                 // for full fee payment
946                 let funders_amount_msat = msg.funding_satoshis * 1000 - msg.push_msat;
947                 let lower_limit = background_feerate as u64 * COMMITMENT_TX_BASE_WEIGHT;
948                 if funders_amount_msat < lower_limit {
949                         return Err(ChannelError::Close(format!("Insufficient funding amount ({}) for initial commitment. Must be at least {}", funders_amount_msat, lower_limit)));
950                 }
951
952                 let to_local_msat = msg.push_msat;
953                 let to_remote_msat = funders_amount_msat - background_feerate as u64 * COMMITMENT_TX_BASE_WEIGHT;
954                 if to_local_msat <= msg.channel_reserve_satoshis * 1000 && to_remote_msat <= holder_selected_channel_reserve_satoshis * 1000 {
955                         return Err(ChannelError::Close("Insufficient funding amount for initial commitment".to_owned()));
956                 }
957
958                 let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() {
959                         match &msg.shutdown_scriptpubkey {
960                                 &OptionalField::Present(ref script) => {
961                                         // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything
962                                         if script.len() == 0 {
963                                                 None
964                                         } else {
965                                                 if !script::is_bolt2_compliant(&script, their_features) {
966                                                         return Err(ChannelError::Close(format!("Peer is signaling upfront_shutdown but has provided an unacceptable scriptpubkey format: {}", script)))
967                                                 }
968                                                 Some(script.clone())
969                                         }
970                                 },
971                                 // 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
972                                 &OptionalField::Absent => {
973                                         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()));
974                                 }
975                         }
976                 } else { None };
977
978                 let shutdown_scriptpubkey = if config.channel_options.commit_upfront_shutdown_pubkey {
979                         Some(keys_provider.get_shutdown_scriptpubkey())
980                 } else { None };
981
982                 if let Some(shutdown_scriptpubkey) = &shutdown_scriptpubkey {
983                         if !shutdown_scriptpubkey.is_compatible(&their_features) {
984                                 return Err(ChannelError::Close(format!("Provided a scriptpubkey format not accepted by peer: {}", shutdown_scriptpubkey)));
985                         }
986                 }
987
988                 let mut secp_ctx = Secp256k1::new();
989                 secp_ctx.seeded_randomize(&keys_provider.get_secure_random_bytes());
990
991                 let chan = Channel {
992                         user_id,
993                         config: local_config,
994
995                         channel_id: msg.temporary_channel_id,
996                         channel_state: (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32),
997                         secp_ctx,
998
999                         latest_monitor_update_id: 0,
1000
1001                         holder_signer,
1002                         shutdown_scriptpubkey,
1003                         destination_script: keys_provider.get_destination_script(),
1004
1005                         cur_holder_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
1006                         cur_counterparty_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
1007                         value_to_self_msat: msg.push_msat,
1008
1009                         pending_inbound_htlcs: Vec::new(),
1010                         pending_outbound_htlcs: Vec::new(),
1011                         holding_cell_htlc_updates: Vec::new(),
1012                         pending_update_fee: None,
1013                         holding_cell_update_fee: None,
1014                         next_holder_htlc_id: 0,
1015                         next_counterparty_htlc_id: 0,
1016                         update_time_counter: 1,
1017
1018                         resend_order: RAACommitmentOrder::CommitmentFirst,
1019
1020                         monitor_pending_funding_locked: false,
1021                         monitor_pending_revoke_and_ack: false,
1022                         monitor_pending_commitment_signed: false,
1023                         monitor_pending_forwards: Vec::new(),
1024                         monitor_pending_failures: Vec::new(),
1025                         monitor_pending_finalized_fulfills: Vec::new(),
1026
1027                         #[cfg(debug_assertions)]
1028                         holder_max_commitment_tx_output: Mutex::new((msg.push_msat, msg.funding_satoshis * 1000 - msg.push_msat)),
1029                         #[cfg(debug_assertions)]
1030                         counterparty_max_commitment_tx_output: Mutex::new((msg.push_msat, msg.funding_satoshis * 1000 - msg.push_msat)),
1031
1032                         last_sent_closing_fee: None,
1033                         pending_counterparty_closing_signed: None,
1034                         closing_fee_limits: None,
1035                         target_closing_feerate_sats_per_kw: None,
1036
1037                         funding_tx_confirmed_in: None,
1038                         funding_tx_confirmation_height: 0,
1039                         short_channel_id: None,
1040                         channel_creation_height: current_chain_height,
1041
1042                         feerate_per_kw: msg.feerate_per_kw,
1043                         channel_value_satoshis: msg.funding_satoshis,
1044                         counterparty_dust_limit_satoshis: msg.dust_limit_satoshis,
1045                         holder_dust_limit_satoshis: MIN_CHAN_DUST_LIMIT_SATOSHIS,
1046                         counterparty_max_htlc_value_in_flight_msat: cmp::min(msg.max_htlc_value_in_flight_msat, msg.funding_satoshis * 1000),
1047                         counterparty_selected_channel_reserve_satoshis: Some(msg.channel_reserve_satoshis),
1048                         counterparty_htlc_minimum_msat: msg.htlc_minimum_msat,
1049                         holder_htlc_minimum_msat: if config.own_channel_config.our_htlc_minimum_msat == 0 { 1 } else { config.own_channel_config.our_htlc_minimum_msat },
1050                         counterparty_max_accepted_htlcs: msg.max_accepted_htlcs,
1051                         minimum_depth: Some(config.own_channel_config.minimum_depth),
1052
1053                         counterparty_forwarding_info: None,
1054
1055                         channel_transaction_parameters: ChannelTransactionParameters {
1056                                 holder_pubkeys: pubkeys,
1057                                 holder_selected_contest_delay: config.own_channel_config.our_to_self_delay,
1058                                 is_outbound_from_holder: false,
1059                                 counterparty_parameters: Some(CounterpartyChannelTransactionParameters {
1060                                         selected_contest_delay: msg.to_self_delay,
1061                                         pubkeys: counterparty_pubkeys,
1062                                 }),
1063                                 funding_outpoint: None
1064                         },
1065                         funding_transaction: None,
1066
1067                         counterparty_cur_commitment_point: Some(msg.first_per_commitment_point),
1068                         counterparty_prev_commitment_point: None,
1069                         counterparty_node_id,
1070
1071                         counterparty_shutdown_scriptpubkey,
1072
1073                         commitment_secrets: CounterpartyCommitmentSecrets::new(),
1074
1075                         channel_update_status: ChannelUpdateStatus::Enabled,
1076                         closing_signed_in_flight: false,
1077
1078                         announcement_sigs: None,
1079
1080                         #[cfg(any(test, feature = "fuzztarget"))]
1081                         next_local_commitment_tx_fee_info_cached: Mutex::new(None),
1082                         #[cfg(any(test, feature = "fuzztarget"))]
1083                         next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
1084
1085                         workaround_lnd_bug_4006: None,
1086
1087                         #[cfg(any(test, feature = "fuzztarget"))]
1088                         historical_inbound_htlc_fulfills: HashSet::new(),
1089
1090                         channel_type,
1091                 };
1092
1093                 Ok(chan)
1094         }
1095
1096         /// Transaction nomenclature is somewhat confusing here as there are many different cases - a
1097         /// transaction is referred to as "a's transaction" implying that a will be able to broadcast
1098         /// the transaction. Thus, b will generally be sending a signature over such a transaction to
1099         /// a, and a can revoke the transaction by providing b the relevant per_commitment_secret. As
1100         /// such, a transaction is generally the result of b increasing the amount paid to a (or adding
1101         /// an HTLC to a).
1102         /// @local is used only to convert relevant internal structures which refer to remote vs local
1103         /// to decide value of outputs and direction of HTLCs.
1104         /// @generated_by_local is used to determine *which* HTLCs to include - noting that the HTLC
1105         /// state may indicate that one peer has informed the other that they'd like to add an HTLC but
1106         /// have not yet committed it. Such HTLCs will only be included in transactions which are being
1107         /// generated by the peer which proposed adding the HTLCs, and thus we need to understand both
1108         /// which peer generated this transaction and "to whom" this transaction flows.
1109         /// Returns (the transaction info, the number of HTLC outputs which were present in the
1110         /// transaction, the list of HTLCs which were not ignored when building the transaction).
1111         /// Note that below-dust HTLCs are included in the fourth return value, but not the third, and
1112         /// sources are provided only for outbound HTLCs in the fourth return value.
1113         #[inline]
1114         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>)>) where L::Target: Logger {
1115                 let mut included_dust_htlcs: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::new();
1116                 let num_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len();
1117                 let mut included_non_dust_htlcs: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::with_capacity(num_htlcs);
1118
1119                 let broadcaster_dust_limit_satoshis = if local { self.holder_dust_limit_satoshis } else { self.counterparty_dust_limit_satoshis };
1120                 let mut remote_htlc_total_msat = 0;
1121                 let mut local_htlc_total_msat = 0;
1122                 let mut value_to_self_msat_offset = 0;
1123
1124                 let mut feerate_per_kw = self.feerate_per_kw;
1125                 if let Some((feerate, update_state)) = self.pending_update_fee {
1126                         if match update_state {
1127                                 // Note that these match the inclusion criteria when scanning
1128                                 // pending_inbound_htlcs below.
1129                                 FeeUpdateState::RemoteAnnounced => { debug_assert!(!self.is_outbound()); !generated_by_local },
1130                                 FeeUpdateState::AwaitingRemoteRevokeToAnnounce => { debug_assert!(!self.is_outbound()); !generated_by_local },
1131                                 FeeUpdateState::Outbound => { assert!(self.is_outbound());  generated_by_local },
1132                         } {
1133                                 feerate_per_kw = feerate;
1134                         }
1135                 }
1136
1137                 log_trace!(logger, "Building commitment transaction number {} (really {} xor {}) for channel {} for {}, generated by {} with fee {}...",
1138                         commitment_number, (INITIAL_COMMITMENT_NUMBER - commitment_number),
1139                         get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound()),
1140                         log_bytes!(self.channel_id), if local { "us" } else { "remote" }, if generated_by_local { "us" } else { "remote" }, feerate_per_kw);
1141
1142                 macro_rules! get_htlc_in_commitment {
1143                         ($htlc: expr, $offered: expr) => {
1144                                 HTLCOutputInCommitment {
1145                                         offered: $offered,
1146                                         amount_msat: $htlc.amount_msat,
1147                                         cltv_expiry: $htlc.cltv_expiry,
1148                                         payment_hash: $htlc.payment_hash,
1149                                         transaction_output_index: None
1150                                 }
1151                         }
1152                 }
1153
1154                 macro_rules! add_htlc_output {
1155                         ($htlc: expr, $outbound: expr, $source: expr, $state_name: expr) => {
1156                                 if $outbound == local { // "offered HTLC output"
1157                                         let htlc_in_tx = get_htlc_in_commitment!($htlc, true);
1158                                         if $htlc.amount_msat / 1000 >= broadcaster_dust_limit_satoshis + (feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) {
1159                                                 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);
1160                                                 included_non_dust_htlcs.push((htlc_in_tx, $source));
1161                                         } else {
1162                                                 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);
1163                                                 included_dust_htlcs.push((htlc_in_tx, $source));
1164                                         }
1165                                 } else {
1166                                         let htlc_in_tx = get_htlc_in_commitment!($htlc, false);
1167                                         if $htlc.amount_msat / 1000 >= broadcaster_dust_limit_satoshis + (feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) {
1168                                                 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);
1169                                                 included_non_dust_htlcs.push((htlc_in_tx, $source));
1170                                         } else {
1171                                                 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);
1172                                                 included_dust_htlcs.push((htlc_in_tx, $source));
1173                                         }
1174                                 }
1175                         }
1176                 }
1177
1178                 for ref htlc in self.pending_inbound_htlcs.iter() {
1179                         let (include, state_name) = match htlc.state {
1180                                 InboundHTLCState::RemoteAnnounced(_) => (!generated_by_local, "RemoteAnnounced"),
1181                                 InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_) => (!generated_by_local, "AwaitingRemoteRevokeToAnnounce"),
1182                                 InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) => (true, "AwaitingAnnouncedRemoteRevoke"),
1183                                 InboundHTLCState::Committed => (true, "Committed"),
1184                                 InboundHTLCState::LocalRemoved(_) => (!generated_by_local, "LocalRemoved"),
1185                         };
1186
1187                         if include {
1188                                 add_htlc_output!(htlc, false, None, state_name);
1189                                 remote_htlc_total_msat += htlc.amount_msat;
1190                         } else {
1191                                 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);
1192                                 match &htlc.state {
1193                                         &InboundHTLCState::LocalRemoved(ref reason) => {
1194                                                 if generated_by_local {
1195                                                         if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
1196                                                                 value_to_self_msat_offset += htlc.amount_msat as i64;
1197                                                         }
1198                                                 }
1199                                         },
1200                                         _ => {},
1201                                 }
1202                         }
1203                 }
1204
1205                 for ref htlc in self.pending_outbound_htlcs.iter() {
1206                         let (include, state_name) = match htlc.state {
1207                                 OutboundHTLCState::LocalAnnounced(_) => (generated_by_local, "LocalAnnounced"),
1208                                 OutboundHTLCState::Committed => (true, "Committed"),
1209                                 OutboundHTLCState::RemoteRemoved(_) => (generated_by_local, "RemoteRemoved"),
1210                                 OutboundHTLCState::AwaitingRemoteRevokeToRemove(_) => (generated_by_local, "AwaitingRemoteRevokeToRemove"),
1211                                 OutboundHTLCState::AwaitingRemovedRemoteRevoke(_) => (false, "AwaitingRemovedRemoteRevoke"),
1212                         };
1213
1214                         if include {
1215                                 add_htlc_output!(htlc, true, Some(&htlc.source), state_name);
1216                                 local_htlc_total_msat += htlc.amount_msat;
1217                         } else {
1218                                 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);
1219                                 match htlc.state {
1220                                         OutboundHTLCState::AwaitingRemoteRevokeToRemove(None)|OutboundHTLCState::AwaitingRemovedRemoteRevoke(None) => {
1221                                                 value_to_self_msat_offset -= htlc.amount_msat as i64;
1222                                         },
1223                                         OutboundHTLCState::RemoteRemoved(None) => {
1224                                                 if !generated_by_local {
1225                                                         value_to_self_msat_offset -= htlc.amount_msat as i64;
1226                                                 }
1227                                         },
1228                                         _ => {},
1229                                 }
1230                         }
1231                 }
1232
1233                 let value_to_self_msat: i64 = (self.value_to_self_msat - local_htlc_total_msat) as i64 + value_to_self_msat_offset;
1234                 assert!(value_to_self_msat >= 0);
1235                 // Note that in case they have several just-awaiting-last-RAA fulfills in-progress (ie
1236                 // AwaitingRemoteRevokeToRemove or AwaitingRemovedRemoteRevoke) we may have allowed them to
1237                 // "violate" their reserve value by couting those against it. Thus, we have to convert
1238                 // everything to i64 before subtracting as otherwise we can overflow.
1239                 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;
1240                 assert!(value_to_remote_msat >= 0);
1241
1242                 #[cfg(debug_assertions)]
1243                 {
1244                         // Make sure that the to_self/to_remote is always either past the appropriate
1245                         // channel_reserve *or* it is making progress towards it.
1246                         let mut broadcaster_max_commitment_tx_output = if generated_by_local {
1247                                 self.holder_max_commitment_tx_output.lock().unwrap()
1248                         } else {
1249                                 self.counterparty_max_commitment_tx_output.lock().unwrap()
1250                         };
1251                         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);
1252                         broadcaster_max_commitment_tx_output.0 = cmp::max(broadcaster_max_commitment_tx_output.0, value_to_self_msat as u64);
1253                         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);
1254                         broadcaster_max_commitment_tx_output.1 = cmp::max(broadcaster_max_commitment_tx_output.1, value_to_remote_msat as u64);
1255                 }
1256
1257                 let total_fee = feerate_per_kw as u64 * (COMMITMENT_TX_BASE_WEIGHT + (included_non_dust_htlcs.len() as u64) * COMMITMENT_TX_WEIGHT_PER_HTLC) / 1000;
1258                 let (value_to_self, value_to_remote) = if self.is_outbound() {
1259                         (value_to_self_msat / 1000 - total_fee as i64, value_to_remote_msat / 1000)
1260                 } else {
1261                         (value_to_self_msat / 1000, value_to_remote_msat / 1000 - total_fee as i64)
1262                 };
1263
1264                 let mut value_to_a = if local { value_to_self } else { value_to_remote };
1265                 let mut value_to_b = if local { value_to_remote } else { value_to_self };
1266                 let (funding_pubkey_a, funding_pubkey_b) = if local {
1267                         (self.get_holder_pubkeys().funding_pubkey, self.get_counterparty_pubkeys().funding_pubkey)
1268                 } else {
1269                         (self.get_counterparty_pubkeys().funding_pubkey, self.get_holder_pubkeys().funding_pubkey)
1270                 };
1271
1272                 if value_to_a >= (broadcaster_dust_limit_satoshis as i64) {
1273                         log_trace!(logger, "   ...including {} output with value {}", if local { "to_local" } else { "to_remote" }, value_to_a);
1274                 } else {
1275                         value_to_a = 0;
1276                 }
1277
1278                 if value_to_b >= (broadcaster_dust_limit_satoshis as i64) {
1279                         log_trace!(logger, "   ...including {} output with value {}", if local { "to_remote" } else { "to_local" }, value_to_b);
1280                 } else {
1281                         value_to_b = 0;
1282                 }
1283
1284                 let num_nondust_htlcs = included_non_dust_htlcs.len();
1285
1286                 let channel_parameters =
1287                         if local { self.channel_transaction_parameters.as_holder_broadcastable() }
1288                         else { self.channel_transaction_parameters.as_counterparty_broadcastable() };
1289                 let tx = CommitmentTransaction::new_with_auxiliary_htlc_data(commitment_number,
1290                                                                              value_to_a as u64,
1291                                                                              value_to_b as u64,
1292                                                                              false,
1293                                                                              funding_pubkey_a,
1294                                                                              funding_pubkey_b,
1295                                                                              keys.clone(),
1296                                                                              feerate_per_kw,
1297                                                                              &mut included_non_dust_htlcs,
1298                                                                              &channel_parameters
1299                 );
1300                 let mut htlcs_included = included_non_dust_htlcs;
1301                 // The unwrap is safe, because all non-dust HTLCs have been assigned an output index
1302                 htlcs_included.sort_unstable_by_key(|h| h.0.transaction_output_index.unwrap());
1303                 htlcs_included.append(&mut included_dust_htlcs);
1304
1305                 (tx, feerate_per_kw, num_nondust_htlcs, htlcs_included)
1306         }
1307
1308         #[inline]
1309         fn get_closing_scriptpubkey(&self) -> Script {
1310                 // The shutdown scriptpubkey is set on channel opening when option_upfront_shutdown_script
1311                 // is signaled. Otherwise, it is set when sending a shutdown message. Calling this method
1312                 // outside of those situations will fail.
1313                 self.shutdown_scriptpubkey.clone().unwrap().into_inner()
1314         }
1315
1316         #[inline]
1317         fn get_closing_transaction_weight(&self, a_scriptpubkey: Option<&Script>, b_scriptpubkey: Option<&Script>) -> u64 {
1318                 let mut ret =
1319                 (4 +                                           // version
1320                  1 +                                           // input count
1321                  36 +                                          // prevout
1322                  1 +                                           // script length (0)
1323                  4 +                                           // sequence
1324                  1 +                                           // output count
1325                  4                                             // lock time
1326                  )*4 +                                         // * 4 for non-witness parts
1327                 2 +                                            // witness marker and flag
1328                 1 +                                            // witness element count
1329                 4 +                                            // 4 element lengths (2 sigs, multisig dummy, and witness script)
1330                 self.get_funding_redeemscript().len() as u64 + // funding witness script
1331                 2*(1 + 71);                                    // two signatures + sighash type flags
1332                 if let Some(spk) = a_scriptpubkey {
1333                         ret += ((8+1) +                            // output values and script length
1334                                 spk.len() as u64) * 4;                 // scriptpubkey and witness multiplier
1335                 }
1336                 if let Some(spk) = b_scriptpubkey {
1337                         ret += ((8+1) +                            // output values and script length
1338                                 spk.len() as u64) * 4;                 // scriptpubkey and witness multiplier
1339                 }
1340                 ret
1341         }
1342
1343         #[inline]
1344         fn build_closing_transaction(&self, proposed_total_fee_satoshis: u64, skip_remote_output: bool) -> (ClosingTransaction, u64) {
1345                 assert!(self.pending_inbound_htlcs.is_empty());
1346                 assert!(self.pending_outbound_htlcs.is_empty());
1347                 assert!(self.pending_update_fee.is_none());
1348
1349                 let mut total_fee_satoshis = proposed_total_fee_satoshis;
1350                 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 };
1351                 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 };
1352
1353                 if value_to_holder < 0 {
1354                         assert!(self.is_outbound());
1355                         total_fee_satoshis += (-value_to_holder) as u64;
1356                 } else if value_to_counterparty < 0 {
1357                         assert!(!self.is_outbound());
1358                         total_fee_satoshis += (-value_to_counterparty) as u64;
1359                 }
1360
1361                 if skip_remote_output || value_to_counterparty as u64 <= self.holder_dust_limit_satoshis {
1362                         value_to_counterparty = 0;
1363                 }
1364
1365                 if value_to_holder as u64 <= self.holder_dust_limit_satoshis {
1366                         value_to_holder = 0;
1367                 }
1368
1369                 assert!(self.shutdown_scriptpubkey.is_some());
1370                 let holder_shutdown_script = self.get_closing_scriptpubkey();
1371                 let counterparty_shutdown_script = self.counterparty_shutdown_scriptpubkey.clone().unwrap();
1372                 let funding_outpoint = self.funding_outpoint().into_bitcoin_outpoint();
1373
1374                 let closing_transaction = ClosingTransaction::new(value_to_holder as u64, value_to_counterparty as u64, holder_shutdown_script, counterparty_shutdown_script, funding_outpoint);
1375                 (closing_transaction, total_fee_satoshis)
1376         }
1377
1378         fn funding_outpoint(&self) -> OutPoint {
1379                 self.channel_transaction_parameters.funding_outpoint.unwrap()
1380         }
1381
1382         #[inline]
1383         /// Creates a set of keys for build_commitment_transaction to generate a transaction which our
1384         /// counterparty will sign (ie DO NOT send signatures over a transaction created by this to
1385         /// our counterparty!)
1386         /// The result is a transaction which we can revoke broadcastership of (ie a "local" transaction)
1387         /// TODO Some magic rust shit to compile-time check this?
1388         fn build_holder_transaction_keys(&self, commitment_number: u64) -> Result<TxCreationKeys, ChannelError> {
1389                 let per_commitment_point = self.holder_signer.get_per_commitment_point(commitment_number, &self.secp_ctx);
1390                 let delayed_payment_base = &self.get_holder_pubkeys().delayed_payment_basepoint;
1391                 let htlc_basepoint = &self.get_holder_pubkeys().htlc_basepoint;
1392                 let counterparty_pubkeys = self.get_counterparty_pubkeys();
1393
1394                 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()))
1395         }
1396
1397         #[inline]
1398         /// Creates a set of keys for build_commitment_transaction to generate a transaction which we
1399         /// will sign and send to our counterparty.
1400         /// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
1401         fn build_remote_transaction_keys(&self) -> Result<TxCreationKeys, ChannelError> {
1402                 //TODO: Ensure that the payment_key derived here ends up in the library users' wallet as we
1403                 //may see payments to it!
1404                 let revocation_basepoint = &self.get_holder_pubkeys().revocation_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, &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()))
1409         }
1410
1411         /// Gets the redeemscript for the funding transaction output (ie the funding transaction output
1412         /// pays to get_funding_redeemscript().to_v0_p2wsh()).
1413         /// Panics if called before accept_channel/new_from_req
1414         pub fn get_funding_redeemscript(&self) -> Script {
1415                 make_funding_redeemscript(&self.get_holder_pubkeys().funding_pubkey, self.counterparty_funding_pubkey())
1416         }
1417
1418         fn get_update_fulfill_htlc<L: Deref>(&mut self, htlc_id_arg: u64, payment_preimage_arg: PaymentPreimage, logger: &L) -> UpdateFulfillFetch where L::Target: Logger {
1419                 // Either ChannelFunded got set (which means it won't be unset) or there is no way any
1420                 // caller thought we could have something claimed (cause we wouldn't have accepted in an
1421                 // incoming HTLC anyway). If we got to ShutdownComplete, callers aren't allowed to call us,
1422                 // either.
1423                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1424                         panic!("Was asked to fulfill an HTLC when channel was not in an operational state");
1425                 }
1426                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
1427
1428                 let payment_hash_calc = PaymentHash(Sha256::hash(&payment_preimage_arg.0[..]).into_inner());
1429
1430                 // ChannelManager may generate duplicate claims/fails due to HTLC update events from
1431                 // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
1432                 // these, but for now we just have to treat them as normal.
1433
1434                 let mut pending_idx = core::usize::MAX;
1435                 let mut htlc_value_msat = 0;
1436                 for (idx, htlc) in self.pending_inbound_htlcs.iter().enumerate() {
1437                         if htlc.htlc_id == htlc_id_arg {
1438                                 assert_eq!(htlc.payment_hash, payment_hash_calc);
1439                                 match htlc.state {
1440                                         InboundHTLCState::Committed => {},
1441                                         InboundHTLCState::LocalRemoved(ref reason) => {
1442                                                 if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
1443                                                 } else {
1444                                                         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()));
1445                                                         debug_assert!(false, "Tried to fulfill an HTLC that was already failed");
1446                                                 }
1447                                                 return UpdateFulfillFetch::DuplicateClaim {};
1448                                         },
1449                                         _ => {
1450                                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1451                                                 // Don't return in release mode here so that we can update channel_monitor
1452                                         }
1453                                 }
1454                                 pending_idx = idx;
1455                                 htlc_value_msat = htlc.amount_msat;
1456                                 break;
1457                         }
1458                 }
1459                 if pending_idx == core::usize::MAX {
1460                         #[cfg(any(test, feature = "fuzztarget"))]
1461                         // If we failed to find an HTLC to fulfill, make sure it was previously fulfilled and
1462                         // this is simply a duplicate claim, not previously failed and we lost funds.
1463                         debug_assert!(self.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
1464                         return UpdateFulfillFetch::DuplicateClaim {};
1465                 }
1466
1467                 // Now update local state:
1468                 //
1469                 // We have to put the payment_preimage in the channel_monitor right away here to ensure we
1470                 // can claim it even if the channel hits the chain before we see their next commitment.
1471                 self.latest_monitor_update_id += 1;
1472                 let monitor_update = ChannelMonitorUpdate {
1473                         update_id: self.latest_monitor_update_id,
1474                         updates: vec![ChannelMonitorUpdateStep::PaymentPreimage {
1475                                 payment_preimage: payment_preimage_arg.clone(),
1476                         }],
1477                 };
1478
1479                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
1480                         for pending_update in self.holding_cell_htlc_updates.iter() {
1481                                 match pending_update {
1482                                         &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
1483                                                 if htlc_id_arg == htlc_id {
1484                                                         // Make sure we don't leave latest_monitor_update_id incremented here:
1485                                                         self.latest_monitor_update_id -= 1;
1486                                                         #[cfg(any(test, feature = "fuzztarget"))]
1487                                                         debug_assert!(self.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
1488                                                         return UpdateFulfillFetch::DuplicateClaim {};
1489                                                 }
1490                                         },
1491                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
1492                                                 if htlc_id_arg == htlc_id {
1493                                                         log_warn!(logger, "Have preimage and want to fulfill HTLC with pending failure against channel {}", log_bytes!(self.channel_id()));
1494                                                         // TODO: We may actually be able to switch to a fulfill here, though its
1495                                                         // rare enough it may not be worth the complexity burden.
1496                                                         debug_assert!(false, "Tried to fulfill an HTLC that was already failed");
1497                                                         return UpdateFulfillFetch::NewClaim { monitor_update, htlc_value_msat, msg: None };
1498                                                 }
1499                                         },
1500                                         _ => {}
1501                                 }
1502                         }
1503                         log_trace!(logger, "Adding HTLC claim to holding_cell in channel {}! Current state: {}", log_bytes!(self.channel_id()), self.channel_state);
1504                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::ClaimHTLC {
1505                                 payment_preimage: payment_preimage_arg, htlc_id: htlc_id_arg,
1506                         });
1507                         #[cfg(any(test, feature = "fuzztarget"))]
1508                         self.historical_inbound_htlc_fulfills.insert(htlc_id_arg);
1509                         return UpdateFulfillFetch::NewClaim { monitor_update, htlc_value_msat, msg: None };
1510                 }
1511                 #[cfg(any(test, feature = "fuzztarget"))]
1512                 self.historical_inbound_htlc_fulfills.insert(htlc_id_arg);
1513
1514                 {
1515                         let htlc = &mut self.pending_inbound_htlcs[pending_idx];
1516                         if let InboundHTLCState::Committed = htlc.state {
1517                         } else {
1518                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1519                                 return UpdateFulfillFetch::NewClaim { monitor_update, htlc_value_msat, msg: None };
1520                         }
1521                         log_trace!(logger, "Upgrading HTLC {} to LocalRemoved with a Fulfill in channel {}!", log_bytes!(htlc.payment_hash.0), log_bytes!(self.channel_id));
1522                         htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::Fulfill(payment_preimage_arg.clone()));
1523                 }
1524
1525                 UpdateFulfillFetch::NewClaim {
1526                         monitor_update,
1527                         htlc_value_msat,
1528                         msg: Some(msgs::UpdateFulfillHTLC {
1529                                 channel_id: self.channel_id(),
1530                                 htlc_id: htlc_id_arg,
1531                                 payment_preimage: payment_preimage_arg,
1532                         }),
1533                 }
1534         }
1535
1536         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 {
1537                 match self.get_update_fulfill_htlc(htlc_id, payment_preimage, logger) {
1538                         UpdateFulfillFetch::NewClaim { mut monitor_update, htlc_value_msat, msg: Some(update_fulfill_htlc) } => {
1539                                 let (commitment, mut additional_update) = match self.send_commitment_no_status_check(logger) {
1540                                         Err(e) => return Err((e, monitor_update)),
1541                                         Ok(res) => res
1542                                 };
1543                                 // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
1544                                 // strictly increasing by one, so decrement it here.
1545                                 self.latest_monitor_update_id = monitor_update.update_id;
1546                                 monitor_update.updates.append(&mut additional_update.updates);
1547                                 Ok(UpdateFulfillCommitFetch::NewClaim { monitor_update, htlc_value_msat, msgs: Some((update_fulfill_htlc, commitment)) })
1548                         },
1549                         UpdateFulfillFetch::NewClaim { monitor_update, htlc_value_msat, msg: None } =>
1550                                 Ok(UpdateFulfillCommitFetch::NewClaim { monitor_update, htlc_value_msat, msgs: None }),
1551                         UpdateFulfillFetch::DuplicateClaim {} => Ok(UpdateFulfillCommitFetch::DuplicateClaim {}),
1552                 }
1553         }
1554
1555         /// We can only have one resolution per HTLC. In some cases around reconnect, we may fulfill
1556         /// an HTLC more than once or fulfill once and then attempt to fail after reconnect. We cannot,
1557         /// however, fail more than once as we wait for an upstream failure to be irrevocably committed
1558         /// before we fail backwards.
1559         /// If we do fail twice, we debug_assert!(false) and return Ok(None). Thus, will always return
1560         /// Ok(_) if debug assertions are turned on or preconditions are met.
1561         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 {
1562                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1563                         panic!("Was asked to fail an HTLC when channel was not in an operational state");
1564                 }
1565                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
1566
1567                 // ChannelManager may generate duplicate claims/fails due to HTLC update events from
1568                 // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
1569                 // these, but for now we just have to treat them as normal.
1570
1571                 let mut pending_idx = core::usize::MAX;
1572                 for (idx, htlc) in self.pending_inbound_htlcs.iter().enumerate() {
1573                         if htlc.htlc_id == htlc_id_arg {
1574                                 match htlc.state {
1575                                         InboundHTLCState::Committed => {},
1576                                         InboundHTLCState::LocalRemoved(ref reason) => {
1577                                                 if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
1578                                                 } else {
1579                                                         debug_assert!(false, "Tried to fail an HTLC that was already failed");
1580                                                 }
1581                                                 return Ok(None);
1582                                         },
1583                                         _ => {
1584                                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1585                                                 return Err(ChannelError::Ignore(format!("Unable to find a pending HTLC which matched the given HTLC ID ({})", htlc.htlc_id)));
1586                                         }
1587                                 }
1588                                 pending_idx = idx;
1589                         }
1590                 }
1591                 if pending_idx == core::usize::MAX {
1592                         #[cfg(any(test, feature = "fuzztarget"))]
1593                         // If we failed to find an HTLC to fail, make sure it was previously fulfilled and this
1594                         // is simply a duplicate fail, not previously failed and we failed-back too early.
1595                         debug_assert!(self.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
1596                         return Ok(None);
1597                 }
1598
1599                 // Now update local state:
1600                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
1601                         for pending_update in self.holding_cell_htlc_updates.iter() {
1602                                 match pending_update {
1603                                         &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
1604                                                 if htlc_id_arg == htlc_id {
1605                                                         #[cfg(any(test, feature = "fuzztarget"))]
1606                                                         debug_assert!(self.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
1607                                                         return Ok(None);
1608                                                 }
1609                                         },
1610                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
1611                                                 if htlc_id_arg == htlc_id {
1612                                                         debug_assert!(false, "Tried to fail an HTLC that was already failed");
1613                                                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
1614                                                 }
1615                                         },
1616                                         _ => {}
1617                                 }
1618                         }
1619                         log_trace!(logger, "Placing failure for HTLC ID {} in holding cell in channel {}.", htlc_id_arg, log_bytes!(self.channel_id()));
1620                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::FailHTLC {
1621                                 htlc_id: htlc_id_arg,
1622                                 err_packet,
1623                         });
1624                         return Ok(None);
1625                 }
1626
1627                 log_trace!(logger, "Failing HTLC ID {} back with a update_fail_htlc message in channel {}.", htlc_id_arg, log_bytes!(self.channel_id()));
1628                 {
1629                         let htlc = &mut self.pending_inbound_htlcs[pending_idx];
1630                         htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(err_packet.clone()));
1631                 }
1632
1633                 Ok(Some(msgs::UpdateFailHTLC {
1634                         channel_id: self.channel_id(),
1635                         htlc_id: htlc_id_arg,
1636                         reason: err_packet
1637                 }))
1638         }
1639
1640         // Message handlers:
1641
1642         pub fn accept_channel(&mut self, msg: &msgs::AcceptChannel, config: &UserConfig, their_features: &InitFeatures) -> Result<(), ChannelError> {
1643                 // Check sanity of message fields:
1644                 if !self.is_outbound() {
1645                         return Err(ChannelError::Close("Got an accept_channel message from an inbound peer".to_owned()));
1646                 }
1647                 if self.channel_state != ChannelState::OurInitSent as u32 {
1648                         return Err(ChannelError::Close("Got an accept_channel message at a strange time".to_owned()));
1649                 }
1650                 if msg.dust_limit_satoshis > 21000000 * 100000000 {
1651                         return Err(ChannelError::Close(format!("Peer never wants payout outputs? dust_limit_satoshis was {}", msg.dust_limit_satoshis)));
1652                 }
1653                 if msg.channel_reserve_satoshis > self.channel_value_satoshis {
1654                         return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must not be greater than ({})", msg.channel_reserve_satoshis, self.channel_value_satoshis)));
1655                 }
1656                 if msg.channel_reserve_satoshis < self.holder_dust_limit_satoshis {
1657                         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)));
1658                 }
1659                 let remote_reserve = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis);
1660                 if msg.dust_limit_satoshis > remote_reserve {
1661                         return Err(ChannelError::Close(format!("Dust limit ({}) is bigger than our channel reserve ({})", msg.dust_limit_satoshis, remote_reserve)));
1662                 }
1663                 let full_channel_value_msat = (self.channel_value_satoshis - msg.channel_reserve_satoshis) * 1000;
1664                 if msg.htlc_minimum_msat >= full_channel_value_msat {
1665                         return Err(ChannelError::Close(format!("Minimum htlc value ({}) is full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat)));
1666                 }
1667                 let max_delay_acceptable = u16::min(config.peer_channel_config_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
1668                 if msg.to_self_delay > max_delay_acceptable {
1669                         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)));
1670                 }
1671                 if msg.max_accepted_htlcs < 1 {
1672                         return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel".to_owned()));
1673                 }
1674                 if msg.max_accepted_htlcs > MAX_HTLCS {
1675                         return Err(ChannelError::Close(format!("max_accepted_htlcs was {}. It must not be larger than {}", msg.max_accepted_htlcs, MAX_HTLCS)));
1676                 }
1677
1678                 // Now check against optional parameters as set by config...
1679                 if msg.htlc_minimum_msat > config.peer_channel_config_limits.max_htlc_minimum_msat {
1680                         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)));
1681                 }
1682                 if msg.max_htlc_value_in_flight_msat < config.peer_channel_config_limits.min_max_htlc_value_in_flight_msat {
1683                         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)));
1684                 }
1685                 if msg.channel_reserve_satoshis > config.peer_channel_config_limits.max_channel_reserve_satoshis {
1686                         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)));
1687                 }
1688                 if msg.max_accepted_htlcs < config.peer_channel_config_limits.min_max_accepted_htlcs {
1689                         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)));
1690                 }
1691                 if msg.dust_limit_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
1692                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the implementation limit ({})", msg.dust_limit_satoshis, MIN_CHAN_DUST_LIMIT_SATOSHIS)));
1693                 }
1694                 if msg.dust_limit_satoshis > MAX_CHAN_DUST_LIMIT_SATOSHIS {
1695                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the implementation limit ({})", msg.dust_limit_satoshis, MAX_CHAN_DUST_LIMIT_SATOSHIS)));
1696                 }
1697                 if msg.minimum_depth > config.peer_channel_config_limits.max_minimum_depth {
1698                         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)));
1699                 }
1700                 if msg.minimum_depth == 0 {
1701                         // Note that if this changes we should update the serialization minimum version to
1702                         // indicate to older clients that they don't understand some features of the current
1703                         // channel.
1704                         return Err(ChannelError::Close("Minimum confirmation depth must be at least 1".to_owned()));
1705                 }
1706
1707                 let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() {
1708                         match &msg.shutdown_scriptpubkey {
1709                                 &OptionalField::Present(ref script) => {
1710                                         // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything
1711                                         if script.len() == 0 {
1712                                                 None
1713                                         } else {
1714                                                 if !script::is_bolt2_compliant(&script, their_features) {
1715                                                         return Err(ChannelError::Close(format!("Peer is signaling upfront_shutdown but has provided an unacceptable scriptpubkey format: {}", script)));
1716                                                 }
1717                                                 Some(script.clone())
1718                                         }
1719                                 },
1720                                 // 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
1721                                 &OptionalField::Absent => {
1722                                         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()));
1723                                 }
1724                         }
1725                 } else { None };
1726
1727                 self.counterparty_dust_limit_satoshis = msg.dust_limit_satoshis;
1728                 self.counterparty_max_htlc_value_in_flight_msat = cmp::min(msg.max_htlc_value_in_flight_msat, self.channel_value_satoshis * 1000);
1729                 self.counterparty_selected_channel_reserve_satoshis = Some(msg.channel_reserve_satoshis);
1730                 self.counterparty_htlc_minimum_msat = msg.htlc_minimum_msat;
1731                 self.counterparty_max_accepted_htlcs = msg.max_accepted_htlcs;
1732                 self.minimum_depth = Some(msg.minimum_depth);
1733
1734                 let counterparty_pubkeys = ChannelPublicKeys {
1735                         funding_pubkey: msg.funding_pubkey,
1736                         revocation_basepoint: msg.revocation_basepoint,
1737                         payment_point: msg.payment_point,
1738                         delayed_payment_basepoint: msg.delayed_payment_basepoint,
1739                         htlc_basepoint: msg.htlc_basepoint
1740                 };
1741
1742                 self.channel_transaction_parameters.counterparty_parameters = Some(CounterpartyChannelTransactionParameters {
1743                         selected_contest_delay: msg.to_self_delay,
1744                         pubkeys: counterparty_pubkeys,
1745                 });
1746
1747                 self.counterparty_cur_commitment_point = Some(msg.first_per_commitment_point);
1748                 self.counterparty_shutdown_scriptpubkey = counterparty_shutdown_scriptpubkey;
1749
1750                 self.channel_state = ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32;
1751
1752                 Ok(())
1753         }
1754
1755         fn funding_created_signature<L: Deref>(&mut self, sig: &Signature, logger: &L) -> Result<(Txid, CommitmentTransaction, Signature), ChannelError> where L::Target: Logger {
1756                 let funding_script = self.get_funding_redeemscript();
1757
1758                 let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number)?;
1759                 let initial_commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, false, logger).0;
1760                 {
1761                         let trusted_tx = initial_commitment_tx.trust();
1762                         let initial_commitment_bitcoin_tx = trusted_tx.built_transaction();
1763                         let sighash = initial_commitment_bitcoin_tx.get_sighash_all(&funding_script, self.channel_value_satoshis);
1764                         // They sign the holder commitment transaction...
1765                         log_trace!(logger, "Checking funding_created tx signature {} by key {} against tx {} (sighash {}) with redeemscript {} for channel {}.",
1766                                 log_bytes!(sig.serialize_compact()[..]), log_bytes!(self.counterparty_funding_pubkey().serialize()),
1767                                 encode::serialize_hex(&initial_commitment_bitcoin_tx.transaction), log_bytes!(sighash[..]),
1768                                 encode::serialize_hex(&funding_script), log_bytes!(self.channel_id()));
1769                         secp_check!(self.secp_ctx.verify(&sighash, &sig, self.counterparty_funding_pubkey()), "Invalid funding_created signature from peer".to_owned());
1770                 }
1771
1772                 let counterparty_keys = self.build_remote_transaction_keys()?;
1773                 let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).0;
1774
1775                 let counterparty_trusted_tx = counterparty_initial_commitment_tx.trust();
1776                 let counterparty_initial_bitcoin_tx = counterparty_trusted_tx.built_transaction();
1777                 log_trace!(logger, "Initial counterparty tx for channel {} is: txid {} tx {}",
1778                         log_bytes!(self.channel_id()), counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
1779
1780                 let counterparty_signature = self.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, &self.secp_ctx)
1781                                 .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0;
1782
1783                 // We sign "counterparty" commitment transaction, allowing them to broadcast the tx if they wish.
1784                 Ok((counterparty_initial_bitcoin_tx.txid, initial_commitment_tx, counterparty_signature))
1785         }
1786
1787         fn counterparty_funding_pubkey(&self) -> &PublicKey {
1788                 &self.get_counterparty_pubkeys().funding_pubkey
1789         }
1790
1791         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 {
1792                 if self.is_outbound() {
1793                         return Err(ChannelError::Close("Received funding_created for an outbound channel?".to_owned()));
1794                 }
1795                 if self.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
1796                         // BOLT 2 says that if we disconnect before we send funding_signed we SHOULD NOT
1797                         // remember the channel, so it's safe to just send an error_message here and drop the
1798                         // channel.
1799                         return Err(ChannelError::Close("Received funding_created after we got the channel!".to_owned()));
1800                 }
1801                 if self.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
1802                                 self.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
1803                                 self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
1804                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
1805                 }
1806
1807                 let funding_txo = OutPoint { txid: msg.funding_txid, index: msg.funding_output_index };
1808                 self.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
1809                 // This is an externally observable change before we finish all our checks.  In particular
1810                 // funding_created_signature may fail.
1811                 self.holder_signer.ready_channel(&self.channel_transaction_parameters);
1812
1813                 let (counterparty_initial_commitment_txid, initial_commitment_tx, signature) = match self.funding_created_signature(&msg.signature, logger) {
1814                         Ok(res) => res,
1815                         Err(ChannelError::Close(e)) => {
1816                                 self.channel_transaction_parameters.funding_outpoint = None;
1817                                 return Err(ChannelError::Close(e));
1818                         },
1819                         Err(e) => {
1820                                 // The only error we know how to handle is ChannelError::Close, so we fall over here
1821                                 // to make sure we don't continue with an inconsistent state.
1822                                 panic!("unexpected error type from funding_created_signature {:?}", e);
1823                         }
1824                 };
1825
1826                 let holder_commitment_tx = HolderCommitmentTransaction::new(
1827                         initial_commitment_tx,
1828                         msg.signature,
1829                         Vec::new(),
1830                         &self.get_holder_pubkeys().funding_pubkey,
1831                         self.counterparty_funding_pubkey()
1832                 );
1833
1834                 self.holder_signer.validate_holder_commitment(&holder_commitment_tx)
1835                         .map_err(|_| ChannelError::Close("Failed to validate our commitment".to_owned()))?;
1836
1837                 // Now that we're past error-generating stuff, update our local state:
1838
1839                 let funding_redeemscript = self.get_funding_redeemscript();
1840                 let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
1841                 let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound());
1842                 let shutdown_script = self.shutdown_scriptpubkey.clone().map(|script| script.into_inner());
1843                 let channel_monitor = ChannelMonitor::new(self.secp_ctx.clone(), self.holder_signer.clone(),
1844                                                           shutdown_script, self.get_holder_selected_contest_delay(),
1845                                                           &self.destination_script, (funding_txo, funding_txo_script.clone()),
1846                                                           &self.channel_transaction_parameters,
1847                                                           funding_redeemscript.clone(), self.channel_value_satoshis,
1848                                                           obscure_factor,
1849                                                           holder_commitment_tx, best_block);
1850
1851                 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);
1852
1853                 self.channel_state = ChannelState::FundingSent as u32;
1854                 self.channel_id = funding_txo.to_channel_id();
1855                 self.cur_counterparty_commitment_transaction_number -= 1;
1856                 self.cur_holder_commitment_transaction_number -= 1;
1857
1858                 log_info!(logger, "Generated funding_signed for peer for channel {}", log_bytes!(self.channel_id()));
1859
1860                 Ok((msgs::FundingSigned {
1861                         channel_id: self.channel_id,
1862                         signature
1863                 }, channel_monitor))
1864         }
1865
1866         /// Handles a funding_signed message from the remote end.
1867         /// If this call is successful, broadcast the funding transaction (and not before!)
1868         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 {
1869                 if !self.is_outbound() {
1870                         return Err(ChannelError::Close("Received funding_signed for an inbound channel?".to_owned()));
1871                 }
1872                 if self.channel_state & !(ChannelState::MonitorUpdateFailed as u32) != ChannelState::FundingCreated as u32 {
1873                         return Err(ChannelError::Close("Received funding_signed in strange state!".to_owned()));
1874                 }
1875                 if self.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
1876                                 self.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
1877                                 self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
1878                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
1879                 }
1880
1881                 let funding_script = self.get_funding_redeemscript();
1882
1883                 let counterparty_keys = self.build_remote_transaction_keys()?;
1884                 let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).0;
1885                 let counterparty_trusted_tx = counterparty_initial_commitment_tx.trust();
1886                 let counterparty_initial_bitcoin_tx = counterparty_trusted_tx.built_transaction();
1887
1888                 log_trace!(logger, "Initial counterparty tx for channel {} is: txid {} tx {}",
1889                         log_bytes!(self.channel_id()), counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
1890
1891                 let holder_signer = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number)?;
1892                 let initial_commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &holder_signer, true, false, logger).0;
1893                 {
1894                         let trusted_tx = initial_commitment_tx.trust();
1895                         let initial_commitment_bitcoin_tx = trusted_tx.built_transaction();
1896                         let sighash = initial_commitment_bitcoin_tx.get_sighash_all(&funding_script, self.channel_value_satoshis);
1897                         // They sign our commitment transaction, allowing us to broadcast the tx if we wish.
1898                         if let Err(_) = self.secp_ctx.verify(&sighash, &msg.signature, &self.get_counterparty_pubkeys().funding_pubkey) {
1899                                 return Err(ChannelError::Close("Invalid funding_signed signature from peer".to_owned()));
1900                         }
1901                 }
1902
1903                 let holder_commitment_tx = HolderCommitmentTransaction::new(
1904                         initial_commitment_tx,
1905                         msg.signature,
1906                         Vec::new(),
1907                         &self.get_holder_pubkeys().funding_pubkey,
1908                         self.counterparty_funding_pubkey()
1909                 );
1910
1911                 self.holder_signer.validate_holder_commitment(&holder_commitment_tx)
1912                         .map_err(|_| ChannelError::Close("Failed to validate our commitment".to_owned()))?;
1913
1914
1915                 let funding_redeemscript = self.get_funding_redeemscript();
1916                 let funding_txo = self.get_funding_txo().unwrap();
1917                 let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
1918                 let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound());
1919                 let shutdown_script = self.shutdown_scriptpubkey.clone().map(|script| script.into_inner());
1920                 let channel_monitor = ChannelMonitor::new(self.secp_ctx.clone(), self.holder_signer.clone(),
1921                                                           shutdown_script, self.get_holder_selected_contest_delay(),
1922                                                           &self.destination_script, (funding_txo, funding_txo_script),
1923                                                           &self.channel_transaction_parameters,
1924                                                           funding_redeemscript.clone(), self.channel_value_satoshis,
1925                                                           obscure_factor,
1926                                                           holder_commitment_tx, best_block);
1927
1928                 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);
1929
1930                 assert_eq!(self.channel_state & (ChannelState::MonitorUpdateFailed as u32), 0); // We have no had any monitor(s) yet to fail update!
1931                 self.channel_state = ChannelState::FundingSent as u32;
1932                 self.cur_holder_commitment_transaction_number -= 1;
1933                 self.cur_counterparty_commitment_transaction_number -= 1;
1934
1935                 log_info!(logger, "Received funding_signed from peer for channel {}", log_bytes!(self.channel_id()));
1936
1937                 Ok((channel_monitor, self.funding_transaction.as_ref().cloned().unwrap()))
1938         }
1939
1940         pub fn funding_locked<L: Deref>(&mut self, msg: &msgs::FundingLocked, logger: &L) -> Result<(), ChannelError> where L::Target: Logger {
1941                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
1942                         self.workaround_lnd_bug_4006 = Some(msg.clone());
1943                         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()));
1944                 }
1945
1946                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
1947
1948                 if non_shutdown_state == ChannelState::FundingSent as u32 {
1949                         self.channel_state |= ChannelState::TheirFundingLocked as u32;
1950                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) {
1951                         self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
1952                         self.update_time_counter += 1;
1953                 } else if (self.channel_state & (ChannelState::ChannelFunded as u32) != 0 &&
1954                                  // Note that funding_signed/funding_created will have decremented both by 1!
1955                                  self.cur_holder_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1 &&
1956                                  self.cur_counterparty_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1) ||
1957                                 // If we reconnected before sending our funding locked they may still resend theirs:
1958                                 (self.channel_state & (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32) ==
1959                                                       (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32)) {
1960                         if self.counterparty_cur_commitment_point != Some(msg.next_per_commitment_point) {
1961                                 return Err(ChannelError::Close("Peer sent a reconnect funding_locked with a different point".to_owned()));
1962                         }
1963                         // They probably disconnected/reconnected and re-sent the funding_locked, which is required
1964                         return Ok(());
1965                 } else {
1966                         return Err(ChannelError::Close("Peer sent a funding_locked at a strange time".to_owned()));
1967                 }
1968
1969                 self.counterparty_prev_commitment_point = self.counterparty_cur_commitment_point;
1970                 self.counterparty_cur_commitment_point = Some(msg.next_per_commitment_point);
1971
1972                 log_info!(logger, "Received funding_locked from peer for channel {}", log_bytes!(self.channel_id()));
1973
1974                 Ok(())
1975         }
1976
1977         /// Returns transaction if there is pending funding transaction that is yet to broadcast
1978         pub fn unbroadcasted_funding(&self) -> Option<Transaction> {
1979                  if self.channel_state & (ChannelState::FundingCreated as u32) != 0 {
1980                          self.funding_transaction.clone()
1981                  } else {
1982                          None
1983                  }
1984         }
1985
1986         /// Returns a HTLCStats about inbound pending htlcs
1987         fn get_inbound_pending_htlc_stats(&self) -> HTLCStats {
1988                 let mut stats = HTLCStats {
1989                         pending_htlcs: self.pending_inbound_htlcs.len() as u32,
1990                         pending_htlcs_value_msat: 0,
1991                         on_counterparty_tx_dust_exposure_msat: 0,
1992                         on_holder_tx_dust_exposure_msat: 0,
1993                 };
1994
1995                 let counterparty_dust_limit_timeout_sat = (self.get_dust_buffer_feerate() as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
1996                 let holder_dust_limit_success_sat = (self.get_dust_buffer_feerate() as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
1997                 for ref htlc in self.pending_inbound_htlcs.iter() {
1998                         stats.pending_htlcs_value_msat += htlc.amount_msat;
1999                         if htlc.amount_msat / 1000 < counterparty_dust_limit_timeout_sat {
2000                                 stats.on_counterparty_tx_dust_exposure_msat += htlc.amount_msat;
2001                         }
2002                         if htlc.amount_msat / 1000 < holder_dust_limit_success_sat {
2003                                 stats.on_holder_tx_dust_exposure_msat += htlc.amount_msat;
2004                         }
2005                 }
2006                 stats
2007         }
2008
2009         /// Returns a HTLCStats about pending outbound htlcs, *including* pending adds in our holding cell.
2010         fn get_outbound_pending_htlc_stats(&self) -> HTLCStats {
2011                 let mut stats = HTLCStats {
2012                         pending_htlcs: self.pending_outbound_htlcs.len() as u32,
2013                         pending_htlcs_value_msat: 0,
2014                         on_counterparty_tx_dust_exposure_msat: 0,
2015                         on_holder_tx_dust_exposure_msat: 0,
2016                 };
2017
2018                 let counterparty_dust_limit_success_sat = (self.get_dust_buffer_feerate() as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
2019                 let holder_dust_limit_timeout_sat = (self.get_dust_buffer_feerate() as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
2020                 for ref htlc in self.pending_outbound_htlcs.iter() {
2021                         stats.pending_htlcs_value_msat += htlc.amount_msat;
2022                         if htlc.amount_msat / 1000 < counterparty_dust_limit_success_sat {
2023                                 stats.on_counterparty_tx_dust_exposure_msat += htlc.amount_msat;
2024                         }
2025                         if htlc.amount_msat / 1000 < holder_dust_limit_timeout_sat {
2026                                 stats.on_holder_tx_dust_exposure_msat += htlc.amount_msat;
2027                         }
2028                 }
2029
2030                 for update in self.holding_cell_htlc_updates.iter() {
2031                         if let &HTLCUpdateAwaitingACK::AddHTLC { ref amount_msat, .. } = update {
2032                                 stats.pending_htlcs += 1;
2033                                 stats.pending_htlcs_value_msat += amount_msat;
2034                                 if *amount_msat / 1000 < counterparty_dust_limit_success_sat {
2035                                         stats.on_counterparty_tx_dust_exposure_msat += amount_msat;
2036                                 }
2037                                 if *amount_msat / 1000 < holder_dust_limit_timeout_sat {
2038                                         stats.on_holder_tx_dust_exposure_msat += amount_msat;
2039                                 }
2040                         }
2041                 }
2042                 stats
2043         }
2044
2045         /// Get the available (ie not including pending HTLCs) inbound and outbound balance in msat.
2046         /// Doesn't bother handling the
2047         /// if-we-removed-it-already-but-haven't-fully-resolved-they-can-still-send-an-inbound-HTLC
2048         /// corner case properly.
2049         pub fn get_inbound_outbound_available_balance_msat(&self) -> (u64, u64) {
2050                 // Note that we have to handle overflow due to the above case.
2051                 (
2052                         cmp::max(self.channel_value_satoshis as i64 * 1000
2053                                 - self.value_to_self_msat as i64
2054                                 - self.get_inbound_pending_htlc_stats().pending_htlcs_value_msat as i64
2055                                 - Self::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis) as i64 * 1000,
2056                         0) as u64,
2057                         cmp::max(self.value_to_self_msat as i64
2058                                 - self.get_outbound_pending_htlc_stats().pending_htlcs_value_msat as i64
2059                                 - self.counterparty_selected_channel_reserve_satoshis.unwrap_or(0) as i64 * 1000,
2060                         0) as u64
2061                 )
2062         }
2063
2064         pub fn get_holder_counterparty_selected_channel_reserve_satoshis(&self) -> (u64, Option<u64>) {
2065                 (Self::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis),
2066                 self.counterparty_selected_channel_reserve_satoshis)
2067         }
2068
2069         // Get the fee cost of a commitment tx with a given number of HTLC outputs.
2070         // Note that num_htlcs should not include dust HTLCs.
2071         fn commit_tx_fee_msat(&self, num_htlcs: usize) -> u64 {
2072                 // Note that we need to divide before multiplying to round properly,
2073                 // since the lowest denomination of bitcoin on-chain is the satoshi.
2074                 (COMMITMENT_TX_BASE_WEIGHT + num_htlcs as u64 * COMMITMENT_TX_WEIGHT_PER_HTLC) * self.feerate_per_kw as u64 / 1000 * 1000
2075         }
2076
2077         // Get the commitment tx fee for the local's (i.e. our) next commitment transaction based on the
2078         // number of pending HTLCs that are on track to be in our next commitment tx, plus an additional
2079         // HTLC if `fee_spike_buffer_htlc` is Some, plus a new HTLC given by `new_htlc_amount`. Dust HTLCs
2080         // are excluded.
2081         fn next_local_commit_tx_fee_msat(&self, htlc: HTLCCandidate, fee_spike_buffer_htlc: Option<()>) -> u64 {
2082                 assert!(self.is_outbound());
2083
2084                 let real_dust_limit_success_sat = (self.feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
2085                 let real_dust_limit_timeout_sat = (self.feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
2086
2087                 let mut addl_htlcs = 0;
2088                 if fee_spike_buffer_htlc.is_some() { addl_htlcs += 1; }
2089                 match htlc.origin {
2090                         HTLCInitiator::LocalOffered => {
2091                                 if htlc.amount_msat / 1000 >= real_dust_limit_timeout_sat {
2092                                         addl_htlcs += 1;
2093                                 }
2094                         },
2095                         HTLCInitiator::RemoteOffered => {
2096                                 if htlc.amount_msat / 1000 >= real_dust_limit_success_sat {
2097                                         addl_htlcs += 1;
2098                                 }
2099                         }
2100                 }
2101
2102                 let mut included_htlcs = 0;
2103                 for ref htlc in self.pending_inbound_htlcs.iter() {
2104                         if htlc.amount_msat / 1000 < real_dust_limit_success_sat {
2105                                 continue
2106                         }
2107                         // We include LocalRemoved HTLCs here because we may still need to broadcast a commitment
2108                         // transaction including this HTLC if it times out before they RAA.
2109                         included_htlcs += 1;
2110                 }
2111
2112                 for ref htlc in self.pending_outbound_htlcs.iter() {
2113                         if htlc.amount_msat / 1000 < real_dust_limit_timeout_sat {
2114                                 continue
2115                         }
2116                         match htlc.state {
2117                                 OutboundHTLCState::LocalAnnounced {..} => included_htlcs += 1,
2118                                 OutboundHTLCState::Committed => included_htlcs += 1,
2119                                 OutboundHTLCState::RemoteRemoved {..} => included_htlcs += 1,
2120                                 // We don't include AwaitingRemoteRevokeToRemove HTLCs because our next commitment
2121                                 // transaction won't be generated until they send us their next RAA, which will mean
2122                                 // dropping any HTLCs in this state.
2123                                 _ => {},
2124                         }
2125                 }
2126
2127                 for htlc in self.holding_cell_htlc_updates.iter() {
2128                         match htlc {
2129                                 &HTLCUpdateAwaitingACK::AddHTLC { amount_msat, .. } => {
2130                                         if amount_msat / 1000 < real_dust_limit_timeout_sat {
2131                                                 continue
2132                                         }
2133                                         included_htlcs += 1
2134                                 },
2135                                 _ => {}, // Don't include claims/fails that are awaiting ack, because once we get the
2136                                          // ack we're guaranteed to never include them in commitment txs anymore.
2137                         }
2138                 }
2139
2140                 let num_htlcs = included_htlcs + addl_htlcs;
2141                 let res = self.commit_tx_fee_msat(num_htlcs);
2142                 #[cfg(any(test, feature = "fuzztarget"))]
2143                 {
2144                         let mut fee = res;
2145                         if fee_spike_buffer_htlc.is_some() {
2146                                 fee = self.commit_tx_fee_msat(num_htlcs - 1);
2147                         }
2148                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len()
2149                                 + self.holding_cell_htlc_updates.len();
2150                         let commitment_tx_info = CommitmentTxInfoCached {
2151                                 fee,
2152                                 total_pending_htlcs,
2153                                 next_holder_htlc_id: match htlc.origin {
2154                                         HTLCInitiator::LocalOffered => self.next_holder_htlc_id + 1,
2155                                         HTLCInitiator::RemoteOffered => self.next_holder_htlc_id,
2156                                 },
2157                                 next_counterparty_htlc_id: match htlc.origin {
2158                                         HTLCInitiator::LocalOffered => self.next_counterparty_htlc_id,
2159                                         HTLCInitiator::RemoteOffered => self.next_counterparty_htlc_id + 1,
2160                                 },
2161                                 feerate: self.feerate_per_kw,
2162                         };
2163                         *self.next_local_commitment_tx_fee_info_cached.lock().unwrap() = Some(commitment_tx_info);
2164                 }
2165                 res
2166         }
2167
2168         // Get the commitment tx fee for the remote's next commitment transaction based on the number of
2169         // pending HTLCs that are on track to be in their next commitment tx, plus an additional HTLC if
2170         // `fee_spike_buffer_htlc` is Some, plus a new HTLC given by `new_htlc_amount`. Dust HTLCs are
2171         // excluded.
2172         fn next_remote_commit_tx_fee_msat(&self, htlc: HTLCCandidate, fee_spike_buffer_htlc: Option<()>) -> u64 {
2173                 assert!(!self.is_outbound());
2174
2175                 let real_dust_limit_success_sat = (self.feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
2176                 let real_dust_limit_timeout_sat = (self.feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
2177
2178                 let mut addl_htlcs = 0;
2179                 if fee_spike_buffer_htlc.is_some() { addl_htlcs += 1; }
2180                 match htlc.origin {
2181                         HTLCInitiator::LocalOffered => {
2182                                 if htlc.amount_msat / 1000 >= real_dust_limit_success_sat {
2183                                         addl_htlcs += 1;
2184                                 }
2185                         },
2186                         HTLCInitiator::RemoteOffered => {
2187                                 if htlc.amount_msat / 1000 >= real_dust_limit_timeout_sat {
2188                                         addl_htlcs += 1;
2189                                 }
2190                         }
2191                 }
2192
2193                 // When calculating the set of HTLCs which will be included in their next commitment_signed, all
2194                 // non-dust inbound HTLCs are included (as all states imply it will be included) and only
2195                 // committed outbound HTLCs, see below.
2196                 let mut included_htlcs = 0;
2197                 for ref htlc in self.pending_inbound_htlcs.iter() {
2198                         if htlc.amount_msat / 1000 <= real_dust_limit_timeout_sat {
2199                                 continue
2200                         }
2201                         included_htlcs += 1;
2202                 }
2203
2204                 for ref htlc in self.pending_outbound_htlcs.iter() {
2205                         if htlc.amount_msat / 1000 <= real_dust_limit_success_sat {
2206                                 continue
2207                         }
2208                         // We only include outbound HTLCs if it will not be included in their next commitment_signed,
2209                         // i.e. if they've responded to us with an RAA after announcement.
2210                         match htlc.state {
2211                                 OutboundHTLCState::Committed => included_htlcs += 1,
2212                                 OutboundHTLCState::RemoteRemoved {..} => included_htlcs += 1,
2213                                 OutboundHTLCState::LocalAnnounced { .. } => included_htlcs += 1,
2214                                 _ => {},
2215                         }
2216                 }
2217
2218                 let num_htlcs = included_htlcs + addl_htlcs;
2219                 let res = self.commit_tx_fee_msat(num_htlcs);
2220                 #[cfg(any(test, feature = "fuzztarget"))]
2221                 {
2222                         let mut fee = res;
2223                         if fee_spike_buffer_htlc.is_some() {
2224                                 fee = self.commit_tx_fee_msat(num_htlcs - 1);
2225                         }
2226                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len();
2227                         let commitment_tx_info = CommitmentTxInfoCached {
2228                                 fee,
2229                                 total_pending_htlcs,
2230                                 next_holder_htlc_id: match htlc.origin {
2231                                         HTLCInitiator::LocalOffered => self.next_holder_htlc_id + 1,
2232                                         HTLCInitiator::RemoteOffered => self.next_holder_htlc_id,
2233                                 },
2234                                 next_counterparty_htlc_id: match htlc.origin {
2235                                         HTLCInitiator::LocalOffered => self.next_counterparty_htlc_id,
2236                                         HTLCInitiator::RemoteOffered => self.next_counterparty_htlc_id + 1,
2237                                 },
2238                                 feerate: self.feerate_per_kw,
2239                         };
2240                         *self.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = Some(commitment_tx_info);
2241                 }
2242                 res
2243         }
2244
2245         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>
2246         where F: for<'a> Fn(&'a Self, PendingHTLCStatus, u16) -> PendingHTLCStatus, L::Target: Logger {
2247                 // We can't accept HTLCs sent after we've sent a shutdown.
2248                 let local_sent_shutdown = (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::LocalShutdownSent as u32)) != (ChannelState::ChannelFunded as u32);
2249                 if local_sent_shutdown {
2250                         pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x4000|8);
2251                 }
2252                 // If the remote has sent a shutdown prior to adding this HTLC, then they are in violation of the spec.
2253                 let remote_sent_shutdown = (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::RemoteShutdownSent as u32)) != (ChannelState::ChannelFunded as u32);
2254                 if remote_sent_shutdown {
2255                         return Err(ChannelError::Close("Got add HTLC message when channel was not in an operational state".to_owned()));
2256                 }
2257                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2258                         return Err(ChannelError::Close("Peer sent update_add_htlc when we needed a channel_reestablish".to_owned()));
2259                 }
2260                 if msg.amount_msat > self.channel_value_satoshis * 1000 {
2261                         return Err(ChannelError::Close("Remote side tried to send more than the total value of the channel".to_owned()));
2262                 }
2263                 if msg.amount_msat == 0 {
2264                         return Err(ChannelError::Close("Remote side tried to send a 0-msat HTLC".to_owned()));
2265                 }
2266                 if msg.amount_msat < self.holder_htlc_minimum_msat {
2267                         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)));
2268                 }
2269
2270                 let inbound_stats = self.get_inbound_pending_htlc_stats();
2271                 let outbound_stats = self.get_outbound_pending_htlc_stats();
2272                 if inbound_stats.pending_htlcs + 1 > OUR_MAX_HTLCS as u32 {
2273                         return Err(ChannelError::Close(format!("Remote tried to push more than our max accepted HTLCs ({})", OUR_MAX_HTLCS)));
2274                 }
2275                 let holder_max_htlc_value_in_flight_msat = Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis);
2276                 if inbound_stats.pending_htlcs_value_msat + msg.amount_msat > holder_max_htlc_value_in_flight_msat {
2277                         return Err(ChannelError::Close(format!("Remote HTLC add would put them over our max HTLC value ({})", holder_max_htlc_value_in_flight_msat)));
2278                 }
2279                 // Check holder_selected_channel_reserve_satoshis (we're getting paid, so they have to at least meet
2280                 // the reserve_satoshis we told them to always have as direct payment so that they lose
2281                 // something if we punish them for broadcasting an old state).
2282                 // Note that we don't really care about having a small/no to_remote output in our local
2283                 // commitment transactions, as the purpose of the channel reserve is to ensure we can
2284                 // punish *them* if they misbehave, so we discount any outbound HTLCs which will not be
2285                 // present in the next commitment transaction we send them (at least for fulfilled ones,
2286                 // failed ones won't modify value_to_self).
2287                 // Note that we will send HTLCs which another instance of rust-lightning would think
2288                 // violate the reserve value if we do not do this (as we forget inbound HTLCs from the
2289                 // Channel state once they will not be present in the next received commitment
2290                 // transaction).
2291                 let mut removed_outbound_total_msat = 0;
2292                 for ref htlc in self.pending_outbound_htlcs.iter() {
2293                         if let OutboundHTLCState::AwaitingRemoteRevokeToRemove(None) = htlc.state {
2294                                 removed_outbound_total_msat += htlc.amount_msat;
2295                         } else if let OutboundHTLCState::AwaitingRemovedRemoteRevoke(None) = htlc.state {
2296                                 removed_outbound_total_msat += htlc.amount_msat;
2297                         }
2298                 }
2299
2300                 let exposure_dust_limit_timeout_sats = (self.get_dust_buffer_feerate() as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
2301                 if msg.amount_msat / 1000 < exposure_dust_limit_timeout_sats {
2302                         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;
2303                         if on_counterparty_tx_dust_htlc_exposure_msat > self.get_max_dust_htlc_exposure_msat() {
2304                                 log_info!(logger, "Cannot accept value that would put our exposure to dust HTLCs at {} over the limit {} on counterparty commitment tx",
2305                                         on_counterparty_tx_dust_htlc_exposure_msat, self.get_max_dust_htlc_exposure_msat());
2306                                 pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|7);
2307                         }
2308                 }
2309
2310                 let exposure_dust_limit_success_sats = (self.get_dust_buffer_feerate() as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
2311                 if msg.amount_msat / 1000 < exposure_dust_limit_success_sats {
2312                         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;
2313                         if on_holder_tx_dust_htlc_exposure_msat > self.get_max_dust_htlc_exposure_msat() {
2314                                 log_info!(logger, "Cannot accept value that would put our exposure to dust HTLCs at {} over the limit {} on holder commitment tx",
2315                                         on_holder_tx_dust_htlc_exposure_msat, self.get_max_dust_htlc_exposure_msat());
2316                                 pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|7);
2317                         }
2318                 }
2319
2320                 let pending_value_to_self_msat =
2321                         self.value_to_self_msat + inbound_stats.pending_htlcs_value_msat - removed_outbound_total_msat;
2322                 let pending_remote_value_msat =
2323                         self.channel_value_satoshis * 1000 - pending_value_to_self_msat;
2324                 if pending_remote_value_msat < msg.amount_msat {
2325                         return Err(ChannelError::Close("Remote HTLC add would overdraw remaining funds".to_owned()));
2326                 }
2327
2328                 // Check that the remote can afford to pay for this HTLC on-chain at the current
2329                 // feerate_per_kw, while maintaining their channel reserve (as required by the spec).
2330                 let remote_commit_tx_fee_msat = if self.is_outbound() { 0 } else {
2331                         let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
2332                         self.next_remote_commit_tx_fee_msat(htlc_candidate, None) // Don't include the extra fee spike buffer HTLC in calculations
2333                 };
2334                 if pending_remote_value_msat - msg.amount_msat < remote_commit_tx_fee_msat {
2335                         return Err(ChannelError::Close("Remote HTLC add would not leave enough to pay for fees".to_owned()));
2336                 };
2337
2338                 let chan_reserve_msat =
2339                         Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis) * 1000;
2340                 if pending_remote_value_msat - msg.amount_msat - remote_commit_tx_fee_msat < chan_reserve_msat {
2341                         return Err(ChannelError::Close("Remote HTLC add would put them under remote reserve value".to_owned()));
2342                 }
2343
2344                 if !self.is_outbound() {
2345                         // `2 *` and `Some(())` is for the fee spike buffer we keep for the remote. This deviates from
2346                         // the spec because in the spec, the fee spike buffer requirement doesn't exist on the
2347                         // receiver's side, only on the sender's.
2348                         // Note that when we eventually remove support for fee updates and switch to anchor output
2349                         // fees, we will drop the `2 *`, since we no longer be as sensitive to fee spikes. But, keep
2350                         // the extra htlc when calculating the next remote commitment transaction fee as we should
2351                         // still be able to afford adding this HTLC plus one more future HTLC, regardless of being
2352                         // sensitive to fee spikes.
2353                         let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
2354                         let remote_fee_cost_incl_stuck_buffer_msat = 2 * self.next_remote_commit_tx_fee_msat(htlc_candidate, Some(()));
2355                         if pending_remote_value_msat - msg.amount_msat - chan_reserve_msat < remote_fee_cost_incl_stuck_buffer_msat {
2356                                 // Note that if the pending_forward_status is not updated here, then it's because we're already failing
2357                                 // the HTLC, i.e. its status is already set to failing.
2358                                 log_info!(logger, "Attempting to fail HTLC due to fee spike buffer violation in channel {}. Rebalancing is required.", log_bytes!(self.channel_id()));
2359                                 pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|7);
2360                         }
2361                 } else {
2362                         // Check that they won't violate our local required channel reserve by adding this HTLC.
2363                         let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
2364                         let local_commit_tx_fee_msat = self.next_local_commit_tx_fee_msat(htlc_candidate, None);
2365                         if self.value_to_self_msat < self.counterparty_selected_channel_reserve_satoshis.unwrap() * 1000 + local_commit_tx_fee_msat {
2366                                 return Err(ChannelError::Close("Cannot accept HTLC that would put our balance under counterparty-announced channel reserve value".to_owned()));
2367                         }
2368                 }
2369                 if self.next_counterparty_htlc_id != msg.htlc_id {
2370                         return Err(ChannelError::Close(format!("Remote skipped HTLC ID (skipped ID: {})", self.next_counterparty_htlc_id)));
2371                 }
2372                 if msg.cltv_expiry >= 500000000 {
2373                         return Err(ChannelError::Close("Remote provided CLTV expiry in seconds instead of block height".to_owned()));
2374                 }
2375
2376                 if self.channel_state & ChannelState::LocalShutdownSent as u32 != 0 {
2377                         if let PendingHTLCStatus::Forward(_) = pending_forward_status {
2378                                 panic!("ChannelManager shouldn't be trying to add a forwardable HTLC after we've started closing");
2379                         }
2380                 }
2381
2382                 // Now update local state:
2383                 self.next_counterparty_htlc_id += 1;
2384                 self.pending_inbound_htlcs.push(InboundHTLCOutput {
2385                         htlc_id: msg.htlc_id,
2386                         amount_msat: msg.amount_msat,
2387                         payment_hash: msg.payment_hash,
2388                         cltv_expiry: msg.cltv_expiry,
2389                         state: InboundHTLCState::RemoteAnnounced(pending_forward_status),
2390                 });
2391                 Ok(())
2392         }
2393
2394         /// Marks an outbound HTLC which we have received update_fail/fulfill/malformed
2395         #[inline]
2396         fn mark_outbound_htlc_removed(&mut self, htlc_id: u64, check_preimage: Option<PaymentHash>, fail_reason: Option<HTLCFailReason>) -> Result<&OutboundHTLCOutput, ChannelError> {
2397                 for htlc in self.pending_outbound_htlcs.iter_mut() {
2398                         if htlc.htlc_id == htlc_id {
2399                                 match check_preimage {
2400                                         None => {},
2401                                         Some(payment_hash) =>
2402                                                 if payment_hash != htlc.payment_hash {
2403                                                         return Err(ChannelError::Close(format!("Remote tried to fulfill HTLC ({}) with an incorrect preimage", htlc_id)));
2404                                                 }
2405                                 };
2406                                 match htlc.state {
2407                                         OutboundHTLCState::LocalAnnounced(_) =>
2408                                                 return Err(ChannelError::Close(format!("Remote tried to fulfill/fail HTLC ({}) before it had been committed", htlc_id))),
2409                                         OutboundHTLCState::Committed => {
2410                                                 htlc.state = OutboundHTLCState::RemoteRemoved(fail_reason);
2411                                         },
2412                                         OutboundHTLCState::AwaitingRemoteRevokeToRemove(_) | OutboundHTLCState::AwaitingRemovedRemoteRevoke(_) | OutboundHTLCState::RemoteRemoved(_) =>
2413                                                 return Err(ChannelError::Close(format!("Remote tried to fulfill/fail HTLC ({}) that they'd already fulfilled/failed", htlc_id))),
2414                                 }
2415                                 return Ok(htlc);
2416                         }
2417                 }
2418                 Err(ChannelError::Close("Remote tried to fulfill/fail an HTLC we couldn't find".to_owned()))
2419         }
2420
2421         pub fn update_fulfill_htlc(&mut self, msg: &msgs::UpdateFulfillHTLC) -> Result<(HTLCSource, u64), ChannelError> {
2422                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2423                         return Err(ChannelError::Close("Got fulfill HTLC message when channel was not in an operational state".to_owned()));
2424                 }
2425                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2426                         return Err(ChannelError::Close("Peer sent update_fulfill_htlc when we needed a channel_reestablish".to_owned()));
2427                 }
2428
2429                 let payment_hash = PaymentHash(Sha256::hash(&msg.payment_preimage.0[..]).into_inner());
2430                 self.mark_outbound_htlc_removed(msg.htlc_id, Some(payment_hash), None).map(|htlc| (htlc.source.clone(), htlc.amount_msat))
2431         }
2432
2433         pub fn update_fail_htlc(&mut self, msg: &msgs::UpdateFailHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> {
2434                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2435                         return Err(ChannelError::Close("Got fail HTLC message when channel was not in an operational state".to_owned()));
2436                 }
2437                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2438                         return Err(ChannelError::Close("Peer sent update_fail_htlc when we needed a channel_reestablish".to_owned()));
2439                 }
2440
2441                 self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason))?;
2442                 Ok(())
2443         }
2444
2445         pub fn update_fail_malformed_htlc(&mut self, msg: &msgs::UpdateFailMalformedHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> {
2446                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2447                         return Err(ChannelError::Close("Got fail malformed 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_fail_malformed_htlc when we needed a channel_reestablish".to_owned()));
2451                 }
2452
2453                 self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason))?;
2454                 Ok(())
2455         }
2456
2457         pub fn commitment_signed<L: Deref>(&mut self, msg: &msgs::CommitmentSigned, logger: &L) -> Result<(msgs::RevokeAndACK, Option<msgs::CommitmentSigned>, ChannelMonitorUpdate), (Option<ChannelMonitorUpdate>, ChannelError)>
2458                 where L::Target: Logger
2459         {
2460                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2461                         return Err((None, ChannelError::Close("Got commitment signed message when channel was not in an operational state".to_owned())));
2462                 }
2463                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2464                         return Err((None, ChannelError::Close("Peer sent commitment_signed when we needed a channel_reestablish".to_owned())));
2465                 }
2466                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() {
2467                         return Err((None, ChannelError::Close("Peer sent commitment_signed after we'd started exchanging closing_signeds".to_owned())));
2468                 }
2469
2470                 let funding_script = self.get_funding_redeemscript();
2471
2472                 let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number).map_err(|e| (None, e))?;
2473
2474                 let (num_htlcs, mut htlcs_cloned, commitment_tx, commitment_txid, feerate_per_kw) = {
2475                         let commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, false, logger);
2476                         let commitment_txid = {
2477                                 let trusted_tx = commitment_tx.0.trust();
2478                                 let bitcoin_tx = trusted_tx.built_transaction();
2479                                 let sighash = bitcoin_tx.get_sighash_all(&funding_script, self.channel_value_satoshis);
2480
2481                                 log_trace!(logger, "Checking commitment tx signature {} by key {} against tx {} (sighash {}) with redeemscript {} in channel {}",
2482                                         log_bytes!(msg.signature.serialize_compact()[..]),
2483                                         log_bytes!(self.counterparty_funding_pubkey().serialize()), encode::serialize_hex(&bitcoin_tx.transaction),
2484                                         log_bytes!(sighash[..]), encode::serialize_hex(&funding_script), log_bytes!(self.channel_id()));
2485                                 if let Err(_) = self.secp_ctx.verify(&sighash, &msg.signature, &self.counterparty_funding_pubkey()) {
2486                                         return Err((None, ChannelError::Close("Invalid commitment tx signature from peer".to_owned())));
2487                                 }
2488                                 bitcoin_tx.txid
2489                         };
2490                         let htlcs_cloned: Vec<_> = commitment_tx.3.iter().map(|htlc| (htlc.0.clone(), htlc.1.map(|h| h.clone()))).collect();
2491                         (commitment_tx.2, htlcs_cloned, commitment_tx.0, commitment_txid, commitment_tx.1)
2492                 };
2493
2494                 // If our counterparty updated the channel fee in this commitment transaction, check that
2495                 // they can actually afford the new fee now.
2496                 let update_fee = if let Some((_, update_state)) = self.pending_update_fee {
2497                         update_state == FeeUpdateState::RemoteAnnounced
2498                 } else { false };
2499                 if update_fee { debug_assert!(!self.is_outbound()); }
2500                 let total_fee = feerate_per_kw as u64 * (COMMITMENT_TX_BASE_WEIGHT + (num_htlcs as u64) * COMMITMENT_TX_WEIGHT_PER_HTLC) / 1000;
2501                 if update_fee {
2502                         let counterparty_reserve_we_require = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis);
2503                         if self.channel_value_satoshis - self.value_to_self_msat / 1000 < total_fee + counterparty_reserve_we_require {
2504                                 return Err((None, ChannelError::Close("Funding remote cannot afford proposed new fee".to_owned())));
2505                         }
2506                 }
2507                 #[cfg(any(test, feature = "fuzztarget"))]
2508                 {
2509                         if self.is_outbound() {
2510                                 let projected_commit_tx_info = self.next_local_commitment_tx_fee_info_cached.lock().unwrap().take();
2511                                 *self.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = None;
2512                                 if let Some(info) = projected_commit_tx_info {
2513                                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len()
2514                                                 + self.holding_cell_htlc_updates.len();
2515                                         if info.total_pending_htlcs == total_pending_htlcs
2516                                                 && info.next_holder_htlc_id == self.next_holder_htlc_id
2517                                                 && info.next_counterparty_htlc_id == self.next_counterparty_htlc_id
2518                                                 && info.feerate == self.feerate_per_kw {
2519                                                         assert_eq!(total_fee, info.fee / 1000);
2520                                                 }
2521                                 }
2522                         }
2523                 }
2524
2525                 if msg.htlc_signatures.len() != num_htlcs {
2526                         return Err((None, ChannelError::Close(format!("Got wrong number of HTLC signatures ({}) from remote. It must be {}", msg.htlc_signatures.len(), num_htlcs))));
2527                 }
2528
2529                 // TODO: Sadly, we pass HTLCs twice to ChannelMonitor: once via the HolderCommitmentTransaction and once via the update
2530                 let mut htlcs_and_sigs = Vec::with_capacity(htlcs_cloned.len());
2531                 for (idx, (htlc, source)) in htlcs_cloned.drain(..).enumerate() {
2532                         if let Some(_) = htlc.transaction_output_index {
2533                                 let htlc_tx = chan_utils::build_htlc_transaction(&commitment_txid, feerate_per_kw,
2534                                         self.get_counterparty_selected_contest_delay().unwrap(), &htlc,
2535                                         &keys.broadcaster_delayed_payment_key, &keys.revocation_key);
2536
2537                                 let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys);
2538                                 let htlc_sighash = hash_to_message!(&bip143::SigHashCache::new(&htlc_tx).signature_hash(0, &htlc_redeemscript, htlc.amount_msat / 1000, SigHashType::All)[..]);
2539                                 log_trace!(logger, "Checking HTLC tx signature {} by key {} against tx {} (sighash {}) with redeemscript {} in channel {}.",
2540                                         log_bytes!(msg.htlc_signatures[idx].serialize_compact()[..]), log_bytes!(keys.countersignatory_htlc_key.serialize()),
2541                                         encode::serialize_hex(&htlc_tx), log_bytes!(htlc_sighash[..]), encode::serialize_hex(&htlc_redeemscript), log_bytes!(self.channel_id()));
2542                                 if let Err(_) = self.secp_ctx.verify(&htlc_sighash, &msg.htlc_signatures[idx], &keys.countersignatory_htlc_key) {
2543                                         return Err((None, ChannelError::Close("Invalid HTLC tx signature from peer".to_owned())));
2544                                 }
2545                                 htlcs_and_sigs.push((htlc, Some(msg.htlc_signatures[idx]), source));
2546                         } else {
2547                                 htlcs_and_sigs.push((htlc, None, source));
2548                         }
2549                 }
2550
2551                 let holder_commitment_tx = HolderCommitmentTransaction::new(
2552                         commitment_tx,
2553                         msg.signature,
2554                         msg.htlc_signatures.clone(),
2555                         &self.get_holder_pubkeys().funding_pubkey,
2556                         self.counterparty_funding_pubkey()
2557                 );
2558
2559                 let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number - 1, &self.secp_ctx);
2560                 self.holder_signer.validate_holder_commitment(&holder_commitment_tx)
2561                         .map_err(|_| (None, ChannelError::Close("Failed to validate our commitment".to_owned())))?;
2562                 let per_commitment_secret = self.holder_signer.release_commitment_secret(self.cur_holder_commitment_transaction_number + 1);
2563
2564                 // Update state now that we've passed all the can-fail calls...
2565                 let mut need_commitment = false;
2566                 if let &mut Some((_, ref mut update_state)) = &mut self.pending_update_fee {
2567                         if *update_state == FeeUpdateState::RemoteAnnounced {
2568                                 *update_state = FeeUpdateState::AwaitingRemoteRevokeToAnnounce;
2569                                 need_commitment = true;
2570                         }
2571                 }
2572
2573                 self.latest_monitor_update_id += 1;
2574                 let mut monitor_update = ChannelMonitorUpdate {
2575                         update_id: self.latest_monitor_update_id,
2576                         updates: vec![ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo {
2577                                 commitment_tx: holder_commitment_tx,
2578                                 htlc_outputs: htlcs_and_sigs
2579                         }]
2580                 };
2581
2582                 for htlc in self.pending_inbound_htlcs.iter_mut() {
2583                         let new_forward = if let &InboundHTLCState::RemoteAnnounced(ref forward_info) = &htlc.state {
2584                                 Some(forward_info.clone())
2585                         } else { None };
2586                         if let Some(forward_info) = new_forward {
2587                                 log_trace!(logger, "Updating HTLC {} to AwaitingRemoteRevokeToAnnounce due to commitment_signed in channel {}.",
2588                                         log_bytes!(htlc.payment_hash.0), log_bytes!(self.channel_id));
2589                                 htlc.state = InboundHTLCState::AwaitingRemoteRevokeToAnnounce(forward_info);
2590                                 need_commitment = true;
2591                         }
2592                 }
2593                 for htlc in self.pending_outbound_htlcs.iter_mut() {
2594                         if let Some(fail_reason) = if let &mut OutboundHTLCState::RemoteRemoved(ref mut fail_reason) = &mut htlc.state {
2595                                 Some(fail_reason.take())
2596                         } else { None } {
2597                                 log_trace!(logger, "Updating HTLC {} to AwaitingRemoteRevokeToRemove due to commitment_signed in channel {}.",
2598                                         log_bytes!(htlc.payment_hash.0), log_bytes!(self.channel_id));
2599                                 htlc.state = OutboundHTLCState::AwaitingRemoteRevokeToRemove(fail_reason);
2600                                 need_commitment = true;
2601                         }
2602                 }
2603
2604                 self.cur_holder_commitment_transaction_number -= 1;
2605                 // Note that if we need_commitment & !AwaitingRemoteRevoke we'll call
2606                 // send_commitment_no_status_check() next which will reset this to RAAFirst.
2607                 self.resend_order = RAACommitmentOrder::CommitmentFirst;
2608
2609                 if (self.channel_state & ChannelState::MonitorUpdateFailed as u32) != 0 {
2610                         // In case we initially failed monitor updating without requiring a response, we need
2611                         // to make sure the RAA gets sent first.
2612                         self.monitor_pending_revoke_and_ack = true;
2613                         if need_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 {
2614                                 // If we were going to send a commitment_signed after the RAA, go ahead and do all
2615                                 // the corresponding HTLC status updates so that get_last_commitment_update
2616                                 // includes the right HTLCs.
2617                                 self.monitor_pending_commitment_signed = true;
2618                                 let (_, mut additional_update) = self.send_commitment_no_status_check(logger).map_err(|e| (None, e))?;
2619                                 // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2620                                 // strictly increasing by one, so decrement it here.
2621                                 self.latest_monitor_update_id = monitor_update.update_id;
2622                                 monitor_update.updates.append(&mut additional_update.updates);
2623                         }
2624                         log_debug!(logger, "Received valid commitment_signed from peer in channel {}, updated HTLC state but awaiting a monitor update resolution to reply.",
2625                                 log_bytes!(self.channel_id));
2626                         return Err((Some(monitor_update), ChannelError::Ignore("Previous monitor update failure prevented generation of RAA".to_owned())));
2627                 }
2628
2629                 let commitment_signed = if need_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 {
2630                         // If we're AwaitingRemoteRevoke we can't send a new commitment here, but that's ok -
2631                         // we'll send one right away when we get the revoke_and_ack when we
2632                         // free_holding_cell_htlcs().
2633                         let (msg, mut additional_update) = self.send_commitment_no_status_check(logger).map_err(|e| (None, e))?;
2634                         // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2635                         // strictly increasing by one, so decrement it here.
2636                         self.latest_monitor_update_id = monitor_update.update_id;
2637                         monitor_update.updates.append(&mut additional_update.updates);
2638                         Some(msg)
2639                 } else { None };
2640
2641                 log_debug!(logger, "Received valid commitment_signed from peer in channel {}, updating HTLC state and responding with{} a revoke_and_ack.",
2642                         log_bytes!(self.channel_id()), if commitment_signed.is_some() { " our own commitment_signed and" } else { "" });
2643
2644                 Ok((msgs::RevokeAndACK {
2645                         channel_id: self.channel_id,
2646                         per_commitment_secret,
2647                         next_per_commitment_point,
2648                 }, commitment_signed, monitor_update))
2649         }
2650
2651         /// Public version of the below, checking relevant preconditions first.
2652         /// If we're not in a state where freeing the holding cell makes sense, this is a no-op and
2653         /// returns `(None, Vec::new())`.
2654         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 {
2655                 if self.channel_state >= ChannelState::ChannelFunded as u32 &&
2656                    (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) == 0 {
2657                         self.free_holding_cell_htlcs(logger)
2658                 } else { Ok((None, Vec::new())) }
2659         }
2660
2661         /// Used to fulfill holding_cell_htlcs when we get a remote ack (or implicitly get it by them
2662         /// fulfilling or failing the last pending HTLC)
2663         fn free_holding_cell_htlcs<L: Deref>(&mut self, logger: &L) -> Result<(Option<(msgs::CommitmentUpdate, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>), ChannelError> where L::Target: Logger {
2664                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, 0);
2665                 if self.holding_cell_htlc_updates.len() != 0 || self.holding_cell_update_fee.is_some() {
2666                         log_trace!(logger, "Freeing holding cell with {} HTLC updates{} in channel {}", self.holding_cell_htlc_updates.len(),
2667                                 if self.holding_cell_update_fee.is_some() { " and a fee update" } else { "" }, log_bytes!(self.channel_id()));
2668
2669                         let mut monitor_update = ChannelMonitorUpdate {
2670                                 update_id: self.latest_monitor_update_id + 1, // We don't increment this yet!
2671                                 updates: Vec::new(),
2672                         };
2673
2674                         let mut htlc_updates = Vec::new();
2675                         mem::swap(&mut htlc_updates, &mut self.holding_cell_htlc_updates);
2676                         let mut update_add_htlcs = Vec::with_capacity(htlc_updates.len());
2677                         let mut update_fulfill_htlcs = Vec::with_capacity(htlc_updates.len());
2678                         let mut update_fail_htlcs = Vec::with_capacity(htlc_updates.len());
2679                         let mut htlcs_to_fail = Vec::new();
2680                         for htlc_update in htlc_updates.drain(..) {
2681                                 // Note that this *can* fail, though it should be due to rather-rare conditions on
2682                                 // fee races with adding too many outputs which push our total payments just over
2683                                 // the limit. In case it's less rare than I anticipate, we may want to revisit
2684                                 // handling this case better and maybe fulfilling some of the HTLCs while attempting
2685                                 // to rebalance channels.
2686                                 match &htlc_update {
2687                                         &HTLCUpdateAwaitingACK::AddHTLC {amount_msat, cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet, ..} => {
2688                                                 match self.send_htlc(amount_msat, *payment_hash, cltv_expiry, source.clone(), onion_routing_packet.clone()) {
2689                                                         Ok(update_add_msg_option) => update_add_htlcs.push(update_add_msg_option.unwrap()),
2690                                                         Err(e) => {
2691                                                                 match e {
2692                                                                         ChannelError::Ignore(ref msg) => {
2693                                                                                 log_info!(logger, "Failed to send HTLC with payment_hash {} due to {} in channel {}",
2694                                                                                         log_bytes!(payment_hash.0), msg, log_bytes!(self.channel_id()));
2695                                                                                 // If we fail to send here, then this HTLC should
2696                                                                                 // be failed backwards. Failing to send here
2697                                                                                 // indicates that this HTLC may keep being put back
2698                                                                                 // into the holding cell without ever being
2699                                                                                 // successfully forwarded/failed/fulfilled, causing
2700                                                                                 // our counterparty to eventually close on us.
2701                                                                                 htlcs_to_fail.push((source.clone(), *payment_hash));
2702                                                                         },
2703                                                                         _ => {
2704                                                                                 panic!("Got a non-IgnoreError action trying to send holding cell HTLC");
2705                                                                         },
2706                                                                 }
2707                                                         }
2708                                                 }
2709                                         },
2710                                         &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, htlc_id, .. } => {
2711                                                 // If an HTLC claim was previously added to the holding cell (via
2712                                                 // `get_update_fulfill_htlc`, then generating the claim message itself must
2713                                                 // not fail - any in between attempts to claim the HTLC will have resulted
2714                                                 // in it hitting the holding cell again and we cannot change the state of a
2715                                                 // holding cell HTLC from fulfill to anything else.
2716                                                 let (update_fulfill_msg_option, mut additional_monitor_update) =
2717                                                         if let UpdateFulfillFetch::NewClaim { msg, monitor_update, .. } = self.get_update_fulfill_htlc(htlc_id, *payment_preimage, logger) {
2718                                                                 (msg, monitor_update)
2719                                                         } else { unreachable!() };
2720                                                 update_fulfill_htlcs.push(update_fulfill_msg_option.unwrap());
2721                                                 monitor_update.updates.append(&mut additional_monitor_update.updates);
2722                                         },
2723                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, ref err_packet } => {
2724                                                 match self.get_update_fail_htlc(htlc_id, err_packet.clone(), logger) {
2725                                                         Ok(update_fail_msg_option) => {
2726                                                                 // If an HTLC failure was previously added to the holding cell (via
2727                                                                 // `get_update_fail_htlc`) then generating the fail message itself
2728                                                                 // must not fail - we should never end up in a state where we
2729                                                                 // double-fail an HTLC or fail-then-claim an HTLC as it indicates
2730                                                                 // we didn't wait for a full revocation before failing.
2731                                                                 update_fail_htlcs.push(update_fail_msg_option.unwrap())
2732                                                         },
2733                                                         Err(e) => {
2734                                                                 if let ChannelError::Ignore(_) = e {}
2735                                                                 else {
2736                                                                         panic!("Got a non-IgnoreError action trying to fail holding cell HTLC");
2737                                                                 }
2738                                                         }
2739                                                 }
2740                                         },
2741                                 }
2742                         }
2743                         if update_add_htlcs.is_empty() && update_fulfill_htlcs.is_empty() && update_fail_htlcs.is_empty() && self.holding_cell_update_fee.is_none() {
2744                                 return Ok((None, htlcs_to_fail));
2745                         }
2746                         let update_fee = if let Some(feerate) = self.holding_cell_update_fee.take() {
2747                                 assert!(self.is_outbound());
2748                                 self.pending_update_fee = Some((feerate, FeeUpdateState::Outbound));
2749                                 Some(msgs::UpdateFee {
2750                                         channel_id: self.channel_id,
2751                                         feerate_per_kw: feerate as u32,
2752                                 })
2753                         } else {
2754                                 None
2755                         };
2756
2757                         let (commitment_signed, mut additional_update) = self.send_commitment_no_status_check(logger)?;
2758                         // send_commitment_no_status_check and get_update_fulfill_htlc may bump latest_monitor_id
2759                         // but we want them to be strictly increasing by one, so reset it here.
2760                         self.latest_monitor_update_id = monitor_update.update_id;
2761                         monitor_update.updates.append(&mut additional_update.updates);
2762
2763                         log_debug!(logger, "Freeing holding cell in channel {} resulted in {}{} HTLCs added, {} HTLCs fulfilled, and {} HTLCs failed.",
2764                                 log_bytes!(self.channel_id()), if update_fee.is_some() { "a fee update, " } else { "" },
2765                                 update_add_htlcs.len(), update_fulfill_htlcs.len(), update_fail_htlcs.len());
2766
2767                         Ok((Some((msgs::CommitmentUpdate {
2768                                 update_add_htlcs,
2769                                 update_fulfill_htlcs,
2770                                 update_fail_htlcs,
2771                                 update_fail_malformed_htlcs: Vec::new(),
2772                                 update_fee,
2773                                 commitment_signed,
2774                         }, monitor_update)), htlcs_to_fail))
2775                 } else {
2776                         Ok((None, Vec::new()))
2777                 }
2778         }
2779
2780         /// Handles receiving a remote's revoke_and_ack. Note that we may return a new
2781         /// commitment_signed message here in case we had pending outbound HTLCs to add which were
2782         /// waiting on this revoke_and_ack. The generation of this new commitment_signed may also fail,
2783         /// generating an appropriate error *after* the channel state has been updated based on the
2784         /// revoke_and_ack message.
2785         pub fn revoke_and_ack<L: Deref>(&mut self, msg: &msgs::RevokeAndACK, logger: &L) -> Result<RAAUpdates, ChannelError>
2786                 where L::Target: Logger,
2787         {
2788                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2789                         return Err(ChannelError::Close("Got revoke/ACK message when channel was not in an operational state".to_owned()));
2790                 }
2791                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2792                         return Err(ChannelError::Close("Peer sent revoke_and_ack when we needed a channel_reestablish".to_owned()));
2793                 }
2794                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() {
2795                         return Err(ChannelError::Close("Peer sent revoke_and_ack after we'd started exchanging closing_signeds".to_owned()));
2796                 }
2797
2798                 let secret = secp_check!(SecretKey::from_slice(&msg.per_commitment_secret), "Peer provided an invalid per_commitment_secret".to_owned());
2799
2800                 if let Some(counterparty_prev_commitment_point) = self.counterparty_prev_commitment_point {
2801                         if PublicKey::from_secret_key(&self.secp_ctx, &secret) != counterparty_prev_commitment_point {
2802                                 return Err(ChannelError::Close("Got a revoke commitment secret which didn't correspond to their current pubkey".to_owned()));
2803                         }
2804                 }
2805
2806                 if self.channel_state & ChannelState::AwaitingRemoteRevoke as u32 == 0 {
2807                         // Our counterparty seems to have burned their coins to us (by revoking a state when we
2808                         // haven't given them a new commitment transaction to broadcast). We should probably
2809                         // take advantage of this by updating our channel monitor, sending them an error, and
2810                         // waiting for them to broadcast their latest (now-revoked claim). But, that would be a
2811                         // lot of work, and there's some chance this is all a misunderstanding anyway.
2812                         // We have to do *something*, though, since our signer may get mad at us for otherwise
2813                         // jumping a remote commitment number, so best to just force-close and move on.
2814                         return Err(ChannelError::Close("Received an unexpected revoke_and_ack".to_owned()));
2815                 }
2816
2817                 #[cfg(any(test, feature = "fuzztarget"))]
2818                 {
2819                         *self.next_local_commitment_tx_fee_info_cached.lock().unwrap() = None;
2820                         *self.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = None;
2821                 }
2822
2823                 self.holder_signer.validate_counterparty_revocation(
2824                         self.cur_counterparty_commitment_transaction_number + 1,
2825                         &secret
2826                 ).map_err(|_| ChannelError::Close("Failed to validate revocation from peer".to_owned()))?;
2827
2828                 self.commitment_secrets.provide_secret(self.cur_counterparty_commitment_transaction_number + 1, msg.per_commitment_secret)
2829                         .map_err(|_| ChannelError::Close("Previous secrets did not match new one".to_owned()))?;
2830                 self.latest_monitor_update_id += 1;
2831                 let mut monitor_update = ChannelMonitorUpdate {
2832                         update_id: self.latest_monitor_update_id,
2833                         updates: vec![ChannelMonitorUpdateStep::CommitmentSecret {
2834                                 idx: self.cur_counterparty_commitment_transaction_number + 1,
2835                                 secret: msg.per_commitment_secret,
2836                         }],
2837                 };
2838
2839                 // Update state now that we've passed all the can-fail calls...
2840                 // (note that we may still fail to generate the new commitment_signed message, but that's
2841                 // OK, we step the channel here and *then* if the new generation fails we can fail the
2842                 // channel based on that, but stepping stuff here should be safe either way.
2843                 self.channel_state &= !(ChannelState::AwaitingRemoteRevoke as u32);
2844                 self.counterparty_prev_commitment_point = self.counterparty_cur_commitment_point;
2845                 self.counterparty_cur_commitment_point = Some(msg.next_per_commitment_point);
2846                 self.cur_counterparty_commitment_transaction_number -= 1;
2847
2848                 log_trace!(logger, "Updating HTLCs on receipt of RAA in channel {}...", log_bytes!(self.channel_id()));
2849                 let mut to_forward_infos = Vec::new();
2850                 let mut revoked_htlcs = Vec::new();
2851                 let mut finalized_claimed_htlcs = Vec::new();
2852                 let mut update_fail_htlcs = Vec::new();
2853                 let mut update_fail_malformed_htlcs = Vec::new();
2854                 let mut require_commitment = false;
2855                 let mut value_to_self_msat_diff: i64 = 0;
2856
2857                 {
2858                         // Take references explicitly so that we can hold multiple references to self.
2859                         let pending_inbound_htlcs: &mut Vec<_> = &mut self.pending_inbound_htlcs;
2860                         let pending_outbound_htlcs: &mut Vec<_> = &mut self.pending_outbound_htlcs;
2861
2862                         // We really shouldnt have two passes here, but retain gives a non-mutable ref (Rust bug)
2863                         pending_inbound_htlcs.retain(|htlc| {
2864                                 if let &InboundHTLCState::LocalRemoved(ref reason) = &htlc.state {
2865                                         log_trace!(logger, " ...removing inbound LocalRemoved {}", log_bytes!(htlc.payment_hash.0));
2866                                         if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
2867                                                 value_to_self_msat_diff += htlc.amount_msat as i64;
2868                                         }
2869                                         false
2870                                 } else { true }
2871                         });
2872                         pending_outbound_htlcs.retain(|htlc| {
2873                                 if let &OutboundHTLCState::AwaitingRemovedRemoteRevoke(ref fail_reason) = &htlc.state {
2874                                         log_trace!(logger, " ...removing outbound AwaitingRemovedRemoteRevoke {}", log_bytes!(htlc.payment_hash.0));
2875                                         if let Some(reason) = fail_reason.clone() { // We really want take() here, but, again, non-mut ref :(
2876                                                 revoked_htlcs.push((htlc.source.clone(), htlc.payment_hash, reason));
2877                                         } else {
2878                                                 finalized_claimed_htlcs.push(htlc.source.clone());
2879                                                 // They fulfilled, so we sent them money
2880                                                 value_to_self_msat_diff -= htlc.amount_msat as i64;
2881                                         }
2882                                         false
2883                                 } else { true }
2884                         });
2885                         for htlc in pending_inbound_htlcs.iter_mut() {
2886                                 let swap = if let &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_) = &htlc.state {
2887                                         true
2888                                 } else if let &InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) = &htlc.state {
2889                                         true
2890                                 } else { false };
2891                                 if swap {
2892                                         let mut state = InboundHTLCState::Committed;
2893                                         mem::swap(&mut state, &mut htlc.state);
2894
2895                                         if let InboundHTLCState::AwaitingRemoteRevokeToAnnounce(forward_info) = state {
2896                                                 log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce {} to AwaitingAnnouncedRemoteRevoke", log_bytes!(htlc.payment_hash.0));
2897                                                 htlc.state = InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info);
2898                                                 require_commitment = true;
2899                                         } else if let InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info) = state {
2900                                                 match forward_info {
2901                                                         PendingHTLCStatus::Fail(fail_msg) => {
2902                                                                 log_trace!(logger, " ...promoting inbound AwaitingAnnouncedRemoteRevoke {} to LocalRemoved due to PendingHTLCStatus indicating failure", log_bytes!(htlc.payment_hash.0));
2903                                                                 require_commitment = true;
2904                                                                 match fail_msg {
2905                                                                         HTLCFailureMsg::Relay(msg) => {
2906                                                                                 htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(msg.reason.clone()));
2907                                                                                 update_fail_htlcs.push(msg)
2908                                                                         },
2909                                                                         HTLCFailureMsg::Malformed(msg) => {
2910                                                                                 htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailMalformed((msg.sha256_of_onion, msg.failure_code)));
2911                                                                                 update_fail_malformed_htlcs.push(msg)
2912                                                                         },
2913                                                                 }
2914                                                         },
2915                                                         PendingHTLCStatus::Forward(forward_info) => {
2916                                                                 log_trace!(logger, " ...promoting inbound AwaitingAnnouncedRemoteRevoke {} to Committed", log_bytes!(htlc.payment_hash.0));
2917                                                                 to_forward_infos.push((forward_info, htlc.htlc_id));
2918                                                                 htlc.state = InboundHTLCState::Committed;
2919                                                         }
2920                                                 }
2921                                         }
2922                                 }
2923                         }
2924                         for htlc in pending_outbound_htlcs.iter_mut() {
2925                                 if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
2926                                         log_trace!(logger, " ...promoting outbound LocalAnnounced {} to Committed", log_bytes!(htlc.payment_hash.0));
2927                                         htlc.state = OutboundHTLCState::Committed;
2928                                 }
2929                                 if let Some(fail_reason) = if let &mut OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref mut fail_reason) = &mut htlc.state {
2930                                         Some(fail_reason.take())
2931                                 } else { None } {
2932                                         log_trace!(logger, " ...promoting outbound AwaitingRemoteRevokeToRemove {} to AwaitingRemovedRemoteRevoke", log_bytes!(htlc.payment_hash.0));
2933                                         htlc.state = OutboundHTLCState::AwaitingRemovedRemoteRevoke(fail_reason);
2934                                         require_commitment = true;
2935                                 }
2936                         }
2937                 }
2938                 self.value_to_self_msat = (self.value_to_self_msat as i64 + value_to_self_msat_diff) as u64;
2939
2940                 if let Some((feerate, update_state)) = self.pending_update_fee {
2941                         match update_state {
2942                                 FeeUpdateState::Outbound => {
2943                                         debug_assert!(self.is_outbound());
2944                                         log_trace!(logger, " ...promoting outbound fee update {} to Committed", feerate);
2945                                         self.feerate_per_kw = feerate;
2946                                         self.pending_update_fee = None;
2947                                 },
2948                                 FeeUpdateState::RemoteAnnounced => { debug_assert!(!self.is_outbound()); },
2949                                 FeeUpdateState::AwaitingRemoteRevokeToAnnounce => {
2950                                         debug_assert!(!self.is_outbound());
2951                                         log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce fee update {} to Committed", feerate);
2952                                         require_commitment = true;
2953                                         self.feerate_per_kw = feerate;
2954                                         self.pending_update_fee = None;
2955                                 },
2956                         }
2957                 }
2958
2959                 if (self.channel_state & ChannelState::MonitorUpdateFailed as u32) == ChannelState::MonitorUpdateFailed as u32 {
2960                         // We can't actually generate a new commitment transaction (incl by freeing holding
2961                         // cells) while we can't update the monitor, so we just return what we have.
2962                         if require_commitment {
2963                                 self.monitor_pending_commitment_signed = true;
2964                                 // When the monitor updating is restored we'll call get_last_commitment_update(),
2965                                 // which does not update state, but we're definitely now awaiting a remote revoke
2966                                 // before we can step forward any more, so set it here.
2967                                 let (_, mut additional_update) = self.send_commitment_no_status_check(logger)?;
2968                                 // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2969                                 // strictly increasing by one, so decrement it here.
2970                                 self.latest_monitor_update_id = monitor_update.update_id;
2971                                 monitor_update.updates.append(&mut additional_update.updates);
2972                         }
2973                         self.monitor_pending_forwards.append(&mut to_forward_infos);
2974                         self.monitor_pending_failures.append(&mut revoked_htlcs);
2975                         self.monitor_pending_finalized_fulfills.append(&mut finalized_claimed_htlcs);
2976                         log_debug!(logger, "Received a valid revoke_and_ack for channel {} but awaiting a monitor update resolution to reply.", log_bytes!(self.channel_id()));
2977                         return Ok(RAAUpdates {
2978                                 commitment_update: None, finalized_claimed_htlcs: Vec::new(),
2979                                 accepted_htlcs: Vec::new(), failed_htlcs: Vec::new(),
2980                                 monitor_update,
2981                                 holding_cell_failed_htlcs: Vec::new()
2982                         });
2983                 }
2984
2985                 match self.free_holding_cell_htlcs(logger)? {
2986                         (Some((mut commitment_update, mut additional_update)), htlcs_to_fail) => {
2987                                 commitment_update.update_fail_htlcs.reserve(update_fail_htlcs.len());
2988                                 for fail_msg in update_fail_htlcs.drain(..) {
2989                                         commitment_update.update_fail_htlcs.push(fail_msg);
2990                                 }
2991                                 commitment_update.update_fail_malformed_htlcs.reserve(update_fail_malformed_htlcs.len());
2992                                 for fail_msg in update_fail_malformed_htlcs.drain(..) {
2993                                         commitment_update.update_fail_malformed_htlcs.push(fail_msg);
2994                                 }
2995
2996                                 // free_holding_cell_htlcs may bump latest_monitor_id multiple times but we want them to be
2997                                 // strictly increasing by one, so decrement it here.
2998                                 self.latest_monitor_update_id = monitor_update.update_id;
2999                                 monitor_update.updates.append(&mut additional_update.updates);
3000
3001                                 Ok(RAAUpdates {
3002                                         commitment_update: Some(commitment_update),
3003                                         finalized_claimed_htlcs,
3004                                         accepted_htlcs: to_forward_infos,
3005                                         failed_htlcs: revoked_htlcs,
3006                                         monitor_update,
3007                                         holding_cell_failed_htlcs: htlcs_to_fail
3008                                 })
3009                         },
3010                         (None, htlcs_to_fail) => {
3011                                 if require_commitment {
3012                                         let (commitment_signed, mut additional_update) = self.send_commitment_no_status_check(logger)?;
3013
3014                                         // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
3015                                         // strictly increasing by one, so decrement it here.
3016                                         self.latest_monitor_update_id = monitor_update.update_id;
3017                                         monitor_update.updates.append(&mut additional_update.updates);
3018
3019                                         log_debug!(logger, "Received a valid revoke_and_ack for channel {}. Responding with a commitment update with {} HTLCs failed.",
3020                                                 log_bytes!(self.channel_id()), update_fail_htlcs.len() + update_fail_malformed_htlcs.len());
3021                                         Ok(RAAUpdates {
3022                                                 commitment_update: Some(msgs::CommitmentUpdate {
3023                                                         update_add_htlcs: Vec::new(),
3024                                                         update_fulfill_htlcs: Vec::new(),
3025                                                         update_fail_htlcs,
3026                                                         update_fail_malformed_htlcs,
3027                                                         update_fee: None,
3028                                                         commitment_signed
3029                                                 }),
3030                                                 finalized_claimed_htlcs,
3031                                                 accepted_htlcs: to_forward_infos, failed_htlcs: revoked_htlcs,
3032                                                 monitor_update, holding_cell_failed_htlcs: htlcs_to_fail
3033                                         })
3034                                 } else {
3035                                         log_debug!(logger, "Received a valid revoke_and_ack for channel {} with no reply necessary.", log_bytes!(self.channel_id()));
3036                                         Ok(RAAUpdates {
3037                                                 commitment_update: None,
3038                                                 finalized_claimed_htlcs,
3039                                                 accepted_htlcs: to_forward_infos, failed_htlcs: revoked_htlcs,
3040                                                 monitor_update, holding_cell_failed_htlcs: htlcs_to_fail
3041                                         })
3042                                 }
3043                         }
3044                 }
3045         }
3046
3047         /// Adds a pending update to this channel. See the doc for send_htlc for
3048         /// further details on the optionness of the return value.
3049         /// You MUST call send_commitment prior to any other calls on this Channel
3050         fn send_update_fee(&mut self, feerate_per_kw: u32) -> Option<msgs::UpdateFee> {
3051                 if !self.is_outbound() {
3052                         panic!("Cannot send fee from inbound channel");
3053                 }
3054                 if !self.is_usable() {
3055                         panic!("Cannot update fee until channel is fully established and we haven't started shutting down");
3056                 }
3057                 if !self.is_live() {
3058                         panic!("Cannot update fee while peer is disconnected/we're awaiting a monitor update (ChannelManager should have caught this)");
3059                 }
3060
3061                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
3062                         self.holding_cell_update_fee = Some(feerate_per_kw);
3063                         return None;
3064                 }
3065
3066                 debug_assert!(self.pending_update_fee.is_none());
3067                 self.pending_update_fee = Some((feerate_per_kw, FeeUpdateState::Outbound));
3068
3069                 Some(msgs::UpdateFee {
3070                         channel_id: self.channel_id,
3071                         feerate_per_kw,
3072                 })
3073         }
3074
3075         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 {
3076                 match self.send_update_fee(feerate_per_kw) {
3077                         Some(update_fee) => {
3078                                 let (commitment_signed, monitor_update) = self.send_commitment_no_status_check(logger)?;
3079                                 Ok(Some((update_fee, commitment_signed, monitor_update)))
3080                         },
3081                         None => Ok(None)
3082                 }
3083         }
3084
3085         /// Removes any uncommitted inbound HTLCs and resets the state of uncommitted outbound HTLC
3086         /// updates, to be used on peer disconnection. After this, update_*_htlc messages need to be
3087         /// resent.
3088         /// No further message handling calls may be made until a channel_reestablish dance has
3089         /// completed.
3090         pub fn remove_uncommitted_htlcs_and_mark_paused<L: Deref>(&mut self, logger: &L)  where L::Target: Logger {
3091                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
3092                 if self.channel_state < ChannelState::FundingSent as u32 {
3093                         self.channel_state = ChannelState::ShutdownComplete as u32;
3094                         return;
3095                 }
3096                 // Upon reconnect we have to start the closing_signed dance over, but shutdown messages
3097                 // will be retransmitted.
3098                 self.last_sent_closing_fee = None;
3099                 self.pending_counterparty_closing_signed = None;
3100                 self.closing_fee_limits = None;
3101
3102                 let mut inbound_drop_count = 0;
3103                 self.pending_inbound_htlcs.retain(|htlc| {
3104                         match htlc.state {
3105                                 InboundHTLCState::RemoteAnnounced(_) => {
3106                                         // They sent us an update_add_htlc but we never got the commitment_signed.
3107                                         // We'll tell them what commitment_signed we're expecting next and they'll drop
3108                                         // this HTLC accordingly
3109                                         inbound_drop_count += 1;
3110                                         false
3111                                 },
3112                                 InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_)|InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) => {
3113                                         // We received a commitment_signed updating this HTLC and (at least hopefully)
3114                                         // sent a revoke_and_ack (which we can re-transmit) and have heard nothing
3115                                         // in response to it yet, so don't touch it.
3116                                         true
3117                                 },
3118                                 InboundHTLCState::Committed => true,
3119                                 InboundHTLCState::LocalRemoved(_) => {
3120                                         // We (hopefully) sent a commitment_signed updating this HTLC (which we can
3121                                         // re-transmit if needed) and they may have even sent a revoke_and_ack back
3122                                         // (that we missed). Keep this around for now and if they tell us they missed
3123                                         // the commitment_signed we can re-transmit the update then.
3124                                         true
3125                                 },
3126                         }
3127                 });
3128                 self.next_counterparty_htlc_id -= inbound_drop_count;
3129
3130                 if let Some((_, update_state)) = self.pending_update_fee {
3131                         if update_state == FeeUpdateState::RemoteAnnounced {
3132                                 debug_assert!(!self.is_outbound());
3133                                 self.pending_update_fee = None;
3134                         }
3135                 }
3136
3137                 for htlc in self.pending_outbound_htlcs.iter_mut() {
3138                         if let OutboundHTLCState::RemoteRemoved(_) = htlc.state {
3139                                 // They sent us an update to remove this but haven't yet sent the corresponding
3140                                 // commitment_signed, we need to move it back to Committed and they can re-send
3141                                 // the update upon reconnection.
3142                                 htlc.state = OutboundHTLCState::Committed;
3143                         }
3144                 }
3145
3146                 self.channel_state |= ChannelState::PeerDisconnected as u32;
3147                 log_trace!(logger, "Peer disconnection resulted in {} remote-announced HTLC drops on channel {}", inbound_drop_count, log_bytes!(self.channel_id()));
3148         }
3149
3150         /// Indicates that a ChannelMonitor update failed to be stored by the client and further
3151         /// updates are partially paused.
3152         /// This must be called immediately after the call which generated the ChannelMonitor update
3153         /// which failed. The messages which were generated from that call which generated the
3154         /// monitor update failure must *not* have been sent to the remote end, and must instead
3155         /// have been dropped. They will be regenerated when monitor_updating_restored is called.
3156         pub fn monitor_update_failed(&mut self, resend_raa: bool, resend_commitment: bool,
3157                 mut pending_forwards: Vec<(PendingHTLCInfo, u64)>,
3158                 mut pending_fails: Vec<(HTLCSource, PaymentHash, HTLCFailReason)>,
3159                 mut pending_finalized_claimed_htlcs: Vec<HTLCSource>
3160         ) {
3161                 self.monitor_pending_revoke_and_ack |= resend_raa;
3162                 self.monitor_pending_commitment_signed |= resend_commitment;
3163                 self.monitor_pending_forwards.append(&mut pending_forwards);
3164                 self.monitor_pending_failures.append(&mut pending_fails);
3165                 self.monitor_pending_finalized_fulfills.append(&mut pending_finalized_claimed_htlcs);
3166                 self.channel_state |= ChannelState::MonitorUpdateFailed as u32;
3167         }
3168
3169         /// Indicates that the latest ChannelMonitor update has been committed by the client
3170         /// successfully and we should restore normal operation. Returns messages which should be sent
3171         /// to the remote side.
3172         pub fn monitor_updating_restored<L: Deref>(&mut self, logger: &L) -> MonitorRestoreUpdates where L::Target: Logger {
3173                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, ChannelState::MonitorUpdateFailed as u32);
3174                 self.channel_state &= !(ChannelState::MonitorUpdateFailed as u32);
3175
3176                 let funding_broadcastable = if self.channel_state & (ChannelState::FundingSent as u32) != 0 && self.is_outbound() {
3177                         self.funding_transaction.take()
3178                 } else { None };
3179
3180                 // We will never broadcast the funding transaction when we're in MonitorUpdateFailed (and
3181                 // we assume the user never directly broadcasts the funding transaction and waits for us to
3182                 // do it). Thus, we can only ever hit monitor_pending_funding_locked when we're an inbound
3183                 // channel which failed to persist the monitor on funding_created, and we got the funding
3184                 // transaction confirmed before the monitor was persisted.
3185                 let funding_locked = if self.monitor_pending_funding_locked {
3186                         assert!(!self.is_outbound(), "Funding transaction broadcast by the local client before it should have - LDK didn't do it!");
3187                         self.monitor_pending_funding_locked = false;
3188                         let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3189                         Some(msgs::FundingLocked {
3190                                 channel_id: self.channel_id(),
3191                                 next_per_commitment_point,
3192                         })
3193                 } else { None };
3194
3195                 let mut accepted_htlcs = Vec::new();
3196                 mem::swap(&mut accepted_htlcs, &mut self.monitor_pending_forwards);
3197                 let mut failed_htlcs = Vec::new();
3198                 mem::swap(&mut failed_htlcs, &mut self.monitor_pending_failures);
3199                 let mut finalized_claimed_htlcs = Vec::new();
3200                 mem::swap(&mut finalized_claimed_htlcs, &mut self.monitor_pending_finalized_fulfills);
3201
3202                 if self.channel_state & (ChannelState::PeerDisconnected as u32) != 0 {
3203                         self.monitor_pending_revoke_and_ack = false;
3204                         self.monitor_pending_commitment_signed = false;
3205                         return MonitorRestoreUpdates {
3206                                 raa: None, commitment_update: None, order: RAACommitmentOrder::RevokeAndACKFirst,
3207                                 accepted_htlcs, failed_htlcs, finalized_claimed_htlcs, funding_broadcastable, funding_locked
3208                         };
3209                 }
3210
3211                 let raa = if self.monitor_pending_revoke_and_ack {
3212                         Some(self.get_last_revoke_and_ack())
3213                 } else { None };
3214                 let commitment_update = if self.monitor_pending_commitment_signed {
3215                         Some(self.get_last_commitment_update(logger))
3216                 } else { None };
3217
3218                 self.monitor_pending_revoke_and_ack = false;
3219                 self.monitor_pending_commitment_signed = false;
3220                 let order = self.resend_order.clone();
3221                 log_debug!(logger, "Restored monitor updating in channel {} resulting in {}{} commitment update and {} RAA, with {} first",
3222                         log_bytes!(self.channel_id()), if funding_broadcastable.is_some() { "a funding broadcastable, " } else { "" },
3223                         if commitment_update.is_some() { "a" } else { "no" }, if raa.is_some() { "an" } else { "no" },
3224                         match order { RAACommitmentOrder::CommitmentFirst => "commitment", RAACommitmentOrder::RevokeAndACKFirst => "RAA"});
3225                 MonitorRestoreUpdates {
3226                         raa, commitment_update, order, accepted_htlcs, failed_htlcs, finalized_claimed_htlcs, funding_broadcastable, funding_locked
3227                 }
3228         }
3229
3230         pub fn update_fee<F: Deref>(&mut self, fee_estimator: &F, msg: &msgs::UpdateFee) -> Result<(), ChannelError>
3231                 where F::Target: FeeEstimator
3232         {
3233                 if self.is_outbound() {
3234                         return Err(ChannelError::Close("Non-funding remote tried to update channel fee".to_owned()));
3235                 }
3236                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
3237                         return Err(ChannelError::Close("Peer sent update_fee when we needed a channel_reestablish".to_owned()));
3238                 }
3239                 Channel::<Signer>::check_remote_fee(fee_estimator, msg.feerate_per_kw)?;
3240                 let feerate_over_dust_buffer = msg.feerate_per_kw > self.get_dust_buffer_feerate();
3241
3242                 self.pending_update_fee = Some((msg.feerate_per_kw, FeeUpdateState::RemoteAnnounced));
3243                 self.update_time_counter += 1;
3244                 // If the feerate has increased over the previous dust buffer (note that
3245                 // `get_dust_buffer_feerate` considers the `pending_update_fee` status), check that we
3246                 // won't be pushed over our dust exposure limit by the feerate increase.
3247                 if feerate_over_dust_buffer {
3248                         let inbound_stats = self.get_inbound_pending_htlc_stats();
3249                         let outbound_stats = self.get_outbound_pending_htlc_stats();
3250                         let holder_tx_dust_exposure = inbound_stats.on_holder_tx_dust_exposure_msat + outbound_stats.on_holder_tx_dust_exposure_msat;
3251                         let counterparty_tx_dust_exposure = inbound_stats.on_counterparty_tx_dust_exposure_msat + outbound_stats.on_counterparty_tx_dust_exposure_msat;
3252                         if holder_tx_dust_exposure > self.get_max_dust_htlc_exposure_msat() {
3253                                 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)",
3254                                         msg.feerate_per_kw, holder_tx_dust_exposure)));
3255                         }
3256                         if counterparty_tx_dust_exposure > self.get_max_dust_htlc_exposure_msat() {
3257                                 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)",
3258                                         msg.feerate_per_kw, counterparty_tx_dust_exposure)));
3259                         }
3260                 }
3261                 Ok(())
3262         }
3263
3264         fn get_last_revoke_and_ack(&self) -> msgs::RevokeAndACK {
3265                 let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3266                 let per_commitment_secret = self.holder_signer.release_commitment_secret(self.cur_holder_commitment_transaction_number + 2);
3267                 msgs::RevokeAndACK {
3268                         channel_id: self.channel_id,
3269                         per_commitment_secret,
3270                         next_per_commitment_point,
3271                 }
3272         }
3273
3274         fn get_last_commitment_update<L: Deref>(&self, logger: &L) -> msgs::CommitmentUpdate where L::Target: Logger {
3275                 let mut update_add_htlcs = Vec::new();
3276                 let mut update_fulfill_htlcs = Vec::new();
3277                 let mut update_fail_htlcs = Vec::new();
3278                 let mut update_fail_malformed_htlcs = Vec::new();
3279
3280                 for htlc in self.pending_outbound_htlcs.iter() {
3281                         if let &OutboundHTLCState::LocalAnnounced(ref onion_packet) = &htlc.state {
3282                                 update_add_htlcs.push(msgs::UpdateAddHTLC {
3283                                         channel_id: self.channel_id(),
3284                                         htlc_id: htlc.htlc_id,
3285                                         amount_msat: htlc.amount_msat,
3286                                         payment_hash: htlc.payment_hash,
3287                                         cltv_expiry: htlc.cltv_expiry,
3288                                         onion_routing_packet: (**onion_packet).clone(),
3289                                 });
3290                         }
3291                 }
3292
3293                 for htlc in self.pending_inbound_htlcs.iter() {
3294                         if let &InboundHTLCState::LocalRemoved(ref reason) = &htlc.state {
3295                                 match reason {
3296                                         &InboundHTLCRemovalReason::FailRelay(ref err_packet) => {
3297                                                 update_fail_htlcs.push(msgs::UpdateFailHTLC {
3298                                                         channel_id: self.channel_id(),
3299                                                         htlc_id: htlc.htlc_id,
3300                                                         reason: err_packet.clone()
3301                                                 });
3302                                         },
3303                                         &InboundHTLCRemovalReason::FailMalformed((ref sha256_of_onion, ref failure_code)) => {
3304                                                 update_fail_malformed_htlcs.push(msgs::UpdateFailMalformedHTLC {
3305                                                         channel_id: self.channel_id(),
3306                                                         htlc_id: htlc.htlc_id,
3307                                                         sha256_of_onion: sha256_of_onion.clone(),
3308                                                         failure_code: failure_code.clone(),
3309                                                 });
3310                                         },
3311                                         &InboundHTLCRemovalReason::Fulfill(ref payment_preimage) => {
3312                                                 update_fulfill_htlcs.push(msgs::UpdateFulfillHTLC {
3313                                                         channel_id: self.channel_id(),
3314                                                         htlc_id: htlc.htlc_id,
3315                                                         payment_preimage: payment_preimage.clone(),
3316                                                 });
3317                                         },
3318                                 }
3319                         }
3320                 }
3321
3322                 let update_fee = if self.is_outbound() && self.pending_update_fee.is_some() {
3323                         Some(msgs::UpdateFee {
3324                                 channel_id: self.channel_id(),
3325                                 feerate_per_kw: self.pending_update_fee.unwrap().0,
3326                         })
3327                 } else { None };
3328
3329                 log_trace!(logger, "Regenerated latest commitment update in channel {} with{} {} update_adds, {} update_fulfills, {} update_fails, and {} update_fail_malformeds",
3330                                 log_bytes!(self.channel_id()), if update_fee.is_some() { " update_fee," } else { "" },
3331                                 update_add_htlcs.len(), update_fulfill_htlcs.len(), update_fail_htlcs.len(), update_fail_malformed_htlcs.len());
3332                 msgs::CommitmentUpdate {
3333                         update_add_htlcs, update_fulfill_htlcs, update_fail_htlcs, update_fail_malformed_htlcs, update_fee,
3334                         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,
3335                 }
3336         }
3337
3338         /// May panic if some calls other than message-handling calls (which will all Err immediately)
3339         /// have been called between remove_uncommitted_htlcs_and_mark_paused and this call.
3340         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 {
3341                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == 0 {
3342                         // While BOLT 2 doesn't indicate explicitly we should error this channel here, it
3343                         // almost certainly indicates we are going to end up out-of-sync in some way, so we
3344                         // just close here instead of trying to recover.
3345                         return Err(ChannelError::Close("Peer sent a loose channel_reestablish not after reconnect".to_owned()));
3346                 }
3347
3348                 if msg.next_local_commitment_number >= INITIAL_COMMITMENT_NUMBER || msg.next_remote_commitment_number >= INITIAL_COMMITMENT_NUMBER ||
3349                         msg.next_local_commitment_number == 0 {
3350                         return Err(ChannelError::Close("Peer sent a garbage channel_reestablish".to_owned()));
3351                 }
3352
3353                 if msg.next_remote_commitment_number > 0 {
3354                         match msg.data_loss_protect {
3355                                 OptionalField::Present(ref data_loss) => {
3356                                         let expected_point = self.holder_signer.get_per_commitment_point(INITIAL_COMMITMENT_NUMBER - msg.next_remote_commitment_number + 1, &self.secp_ctx);
3357                                         let given_secret = SecretKey::from_slice(&data_loss.your_last_per_commitment_secret)
3358                                                 .map_err(|_| ChannelError::Close("Peer sent a garbage channel_reestablish with unparseable secret key".to_owned()))?;
3359                                         if expected_point != PublicKey::from_secret_key(&self.secp_ctx, &given_secret) {
3360                                                 return Err(ChannelError::Close("Peer sent a garbage channel_reestablish with secret key not matching the commitment height provided".to_owned()));
3361                                         }
3362                                         if msg.next_remote_commitment_number > INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number {
3363                                                 return Err(ChannelError::CloseDelayBroadcast(
3364                                                         "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()
3365                                                 ));
3366                                         }
3367                                 },
3368                                 OptionalField::Absent => {}
3369                         }
3370                 }
3371
3372                 // Go ahead and unmark PeerDisconnected as various calls we may make check for it (and all
3373                 // remaining cases either succeed or ErrorMessage-fail).
3374                 self.channel_state &= !(ChannelState::PeerDisconnected as u32);
3375
3376                 let shutdown_msg = if self.channel_state & (ChannelState::LocalShutdownSent as u32) != 0 {
3377                         assert!(self.shutdown_scriptpubkey.is_some());
3378                         Some(msgs::Shutdown {
3379                                 channel_id: self.channel_id,
3380                                 scriptpubkey: self.get_closing_scriptpubkey(),
3381                         })
3382                 } else { None };
3383
3384                 if self.channel_state & (ChannelState::FundingSent as u32) == ChannelState::FundingSent as u32 {
3385                         // If we're waiting on a monitor update, we shouldn't re-send any funding_locked's.
3386                         if self.channel_state & (ChannelState::OurFundingLocked as u32) == 0 ||
3387                                         self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
3388                                 if msg.next_remote_commitment_number != 0 {
3389                                         return Err(ChannelError::Close("Peer claimed they saw a revoke_and_ack but we haven't sent funding_locked yet".to_owned()));
3390                                 }
3391                                 // Short circuit the whole handler as there is nothing we can resend them
3392                                 return Ok((None, None, None, None, RAACommitmentOrder::CommitmentFirst, Vec::new(), shutdown_msg));
3393                         }
3394
3395                         // We have OurFundingLocked set!
3396                         let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3397                         return Ok((Some(msgs::FundingLocked {
3398                                 channel_id: self.channel_id(),
3399                                 next_per_commitment_point,
3400                         }), None, None, None, RAACommitmentOrder::CommitmentFirst, Vec::new(), shutdown_msg));
3401                 }
3402
3403                 let required_revoke = if msg.next_remote_commitment_number + 1 == INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number {
3404                         // Remote isn't waiting on any RevokeAndACK from us!
3405                         // Note that if we need to repeat our FundingLocked we'll do that in the next if block.
3406                         None
3407                 } else if msg.next_remote_commitment_number + 1 == (INITIAL_COMMITMENT_NUMBER - 1) - self.cur_holder_commitment_transaction_number {
3408                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
3409                                 self.monitor_pending_revoke_and_ack = true;
3410                                 None
3411                         } else {
3412                                 Some(self.get_last_revoke_and_ack())
3413                         }
3414                 } else {
3415                         return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old local commitment transaction".to_owned()));
3416                 };
3417
3418                 // We increment cur_counterparty_commitment_transaction_number only upon receipt of
3419                 // revoke_and_ack, not on sending commitment_signed, so we add one if have
3420                 // AwaitingRemoteRevoke set, which indicates we sent a commitment_signed but haven't gotten
3421                 // the corresponding revoke_and_ack back yet.
3422                 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 };
3423
3424                 let resend_funding_locked = if msg.next_local_commitment_number == 1 && INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number == 1 {
3425                         // We should never have to worry about MonitorUpdateFailed resending FundingLocked
3426                         let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3427                         Some(msgs::FundingLocked {
3428                                 channel_id: self.channel_id(),
3429                                 next_per_commitment_point,
3430                         })
3431                 } else { None };
3432
3433                 if msg.next_local_commitment_number == next_counterparty_commitment_number {
3434                         if required_revoke.is_some() {
3435                                 log_debug!(logger, "Reconnected channel {} with only lost outbound RAA", log_bytes!(self.channel_id()));
3436                         } else {
3437                                 log_debug!(logger, "Reconnected channel {} with no loss", log_bytes!(self.channel_id()));
3438                         }
3439
3440                         if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateFailed as u32)) == 0 {
3441                                 // We're up-to-date and not waiting on a remote revoke (if we are our
3442                                 // channel_reestablish should result in them sending a revoke_and_ack), but we may
3443                                 // have received some updates while we were disconnected. Free the holding cell
3444                                 // now!
3445                                 match self.free_holding_cell_htlcs(logger) {
3446                                         Err(ChannelError::Close(msg)) => return Err(ChannelError::Close(msg)),
3447                                         Err(ChannelError::Warn(_)) | Err(ChannelError::Ignore(_)) | Err(ChannelError::CloseDelayBroadcast(_)) =>
3448                                                 panic!("Got non-channel-failing result from free_holding_cell_htlcs"),
3449                                         Ok((Some((commitment_update, monitor_update)), htlcs_to_fail)) => {
3450                                                 return Ok((resend_funding_locked, required_revoke, Some(commitment_update), Some(monitor_update), self.resend_order.clone(), htlcs_to_fail, shutdown_msg));
3451                                         },
3452                                         Ok((None, htlcs_to_fail)) => {
3453                                                 return Ok((resend_funding_locked, required_revoke, None, None, self.resend_order.clone(), htlcs_to_fail, shutdown_msg));
3454                                         },
3455                                 }
3456                         } else {
3457                                 return Ok((resend_funding_locked, required_revoke, None, None, self.resend_order.clone(), Vec::new(), shutdown_msg));
3458                         }
3459                 } else if msg.next_local_commitment_number == next_counterparty_commitment_number - 1 {
3460                         if required_revoke.is_some() {
3461                                 log_debug!(logger, "Reconnected channel {} with lost outbound RAA and lost remote commitment tx", log_bytes!(self.channel_id()));
3462                         } else {
3463                                 log_debug!(logger, "Reconnected channel {} with only lost remote commitment tx", log_bytes!(self.channel_id()));
3464                         }
3465
3466                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
3467                                 self.monitor_pending_commitment_signed = true;
3468                                 return Ok((resend_funding_locked, None, None, None, self.resend_order.clone(), Vec::new(), shutdown_msg));
3469                         }
3470
3471                         return Ok((resend_funding_locked, required_revoke, Some(self.get_last_commitment_update(logger)), None, self.resend_order.clone(), Vec::new(), shutdown_msg));
3472                 } else {
3473                         return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old remote commitment transaction".to_owned()));
3474                 }
3475         }
3476
3477         /// Calculates and returns our minimum and maximum closing transaction fee amounts, in whole
3478         /// satoshis. The amounts remain consistent unless a peer disconnects/reconnects or we restart,
3479         /// at which point they will be recalculated.
3480         fn calculate_closing_fee_limits<F: Deref>(&mut self, fee_estimator: &F) -> (u64, u64)
3481                 where F::Target: FeeEstimator
3482         {
3483                 if let Some((min, max)) = self.closing_fee_limits { return (min, max); }
3484
3485                 // Propose a range from our current Background feerate to our Normal feerate plus our
3486                 // force_close_avoidance_max_fee_satoshis.
3487                 // If we fail to come to consensus, we'll have to force-close.
3488                 let mut proposed_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
3489                 let normal_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
3490                 let mut proposed_max_feerate = if self.is_outbound() { normal_feerate } else { u32::max_value() };
3491
3492                 // The spec requires that (when the channel does not have anchors) we only send absolute
3493                 // channel fees no greater than the absolute channel fee on the current commitment
3494                 // transaction. It's unclear *which* commitment transaction this refers to, and there isn't
3495                 // very good reason to apply such a limit in any case. We don't bother doing so, risking
3496                 // some force-closure by old nodes, but we wanted to close the channel anyway.
3497
3498                 if let Some(target_feerate) = self.target_closing_feerate_sats_per_kw {
3499                         let min_feerate = if self.is_outbound() { target_feerate } else { cmp::min(self.feerate_per_kw, target_feerate) };
3500                         proposed_feerate = cmp::max(proposed_feerate, min_feerate);
3501                         proposed_max_feerate = cmp::max(proposed_max_feerate, min_feerate);
3502                 }
3503
3504                 // Note that technically we could end up with a lower minimum fee if one sides' balance is
3505                 // below our dust limit, causing the output to disappear. We don't bother handling this
3506                 // case, however, as this should only happen if a channel is closed before any (material)
3507                 // payments have been made on it. This may cause slight fee overpayment and/or failure to
3508                 // come to consensus with our counterparty on appropriate fees, however it should be a
3509                 // relatively rare case. We can revisit this later, though note that in order to determine
3510                 // if the funders' output is dust we have to know the absolute fee we're going to use.
3511                 let tx_weight = self.get_closing_transaction_weight(Some(&self.get_closing_scriptpubkey()), Some(self.counterparty_shutdown_scriptpubkey.as_ref().unwrap()));
3512                 let proposed_total_fee_satoshis = proposed_feerate as u64 * tx_weight / 1000;
3513                 let proposed_max_total_fee_satoshis = if self.is_outbound() {
3514                                 // We always add force_close_avoidance_max_fee_satoshis to our normal
3515                                 // feerate-calculated fee, but allow the max to be overridden if we're using a
3516                                 // target feerate-calculated fee.
3517                                 cmp::max(normal_feerate as u64 * tx_weight / 1000 + self.config.force_close_avoidance_max_fee_satoshis,
3518                                         proposed_max_feerate as u64 * tx_weight / 1000)
3519                         } else {
3520                                 self.channel_value_satoshis - (self.value_to_self_msat + 999) / 1000
3521                         };
3522
3523                 self.closing_fee_limits = Some((proposed_total_fee_satoshis, proposed_max_total_fee_satoshis));
3524                 self.closing_fee_limits.clone().unwrap()
3525         }
3526
3527         /// Returns true if we're ready to commence the closing_signed negotiation phase. This is true
3528         /// after both sides have exchanged a `shutdown` message and all HTLCs have been drained. At
3529         /// this point if we're the funder we should send the initial closing_signed, and in any case
3530         /// shutdown should complete within a reasonable timeframe.
3531         fn closing_negotiation_ready(&self) -> bool {
3532                 self.pending_inbound_htlcs.is_empty() && self.pending_outbound_htlcs.is_empty() &&
3533                         self.channel_state &
3534                                 (BOTH_SIDES_SHUTDOWN_MASK | ChannelState::AwaitingRemoteRevoke as u32 |
3535                                  ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)
3536                                 == BOTH_SIDES_SHUTDOWN_MASK &&
3537                         self.pending_update_fee.is_none()
3538         }
3539
3540         /// Checks if the closing_signed negotiation is making appropriate progress, possibly returning
3541         /// an Err if no progress is being made and the channel should be force-closed instead.
3542         /// Should be called on a one-minute timer.
3543         pub fn timer_check_closing_negotiation_progress(&mut self) -> Result<(), ChannelError> {
3544                 if self.closing_negotiation_ready() {
3545                         if self.closing_signed_in_flight {
3546                                 return Err(ChannelError::Close("closing_signed negotiation failed to finish within two timer ticks".to_owned()));
3547                         } else {
3548                                 self.closing_signed_in_flight = true;
3549                         }
3550                 }
3551                 Ok(())
3552         }
3553
3554         pub fn maybe_propose_closing_signed<F: Deref, L: Deref>(&mut self, fee_estimator: &F, logger: &L)
3555                 -> Result<(Option<msgs::ClosingSigned>, Option<Transaction>), ChannelError>
3556                 where F::Target: FeeEstimator, L::Target: Logger
3557         {
3558                 if self.last_sent_closing_fee.is_some() || !self.closing_negotiation_ready() {
3559                         return Ok((None, None));
3560                 }
3561
3562                 if !self.is_outbound() {
3563                         if let Some(msg) = &self.pending_counterparty_closing_signed.take() {
3564                                 return self.closing_signed(fee_estimator, &msg);
3565                         }
3566                         return Ok((None, None));
3567                 }
3568
3569                 let (our_min_fee, our_max_fee) = self.calculate_closing_fee_limits(fee_estimator);
3570
3571                 assert!(self.shutdown_scriptpubkey.is_some());
3572                 let (closing_tx, total_fee_satoshis) = self.build_closing_transaction(our_min_fee, false);
3573                 log_trace!(logger, "Proposing initial closing_signed for our counterparty with a fee range of {}-{} sat (with initial proposal {} sats)",
3574                         our_min_fee, our_max_fee, total_fee_satoshis);
3575
3576                 let sig = self.holder_signer
3577                         .sign_closing_transaction(&closing_tx, &self.secp_ctx)
3578                         .map_err(|()| ChannelError::Close("Failed to get signature for closing transaction.".to_owned()))?;
3579
3580                 self.last_sent_closing_fee = Some((total_fee_satoshis, sig.clone()));
3581                 Ok((Some(msgs::ClosingSigned {
3582                         channel_id: self.channel_id,
3583                         fee_satoshis: total_fee_satoshis,
3584                         signature: sig,
3585                         fee_range: Some(msgs::ClosingSignedFeeRange {
3586                                 min_fee_satoshis: our_min_fee,
3587                                 max_fee_satoshis: our_max_fee,
3588                         }),
3589                 }), None))
3590         }
3591
3592         pub fn shutdown<K: Deref>(
3593                 &mut self, keys_provider: &K, their_features: &InitFeatures, msg: &msgs::Shutdown
3594         ) -> Result<(Option<msgs::Shutdown>, Option<ChannelMonitorUpdate>, Vec<(HTLCSource, PaymentHash)>), ChannelError>
3595         where K::Target: KeysInterface<Signer = Signer>
3596         {
3597                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
3598                         return Err(ChannelError::Close("Peer sent shutdown when we needed a channel_reestablish".to_owned()));
3599                 }
3600                 if self.channel_state < ChannelState::FundingSent as u32 {
3601                         // Spec says we should fail the connection, not the channel, but that's nonsense, there
3602                         // are plenty of reasons you may want to fail a channel pre-funding, and spec says you
3603                         // can do that via error message without getting a connection fail anyway...
3604                         return Err(ChannelError::Close("Peer sent shutdown pre-funding generation".to_owned()));
3605                 }
3606                 for htlc in self.pending_inbound_htlcs.iter() {
3607                         if let InboundHTLCState::RemoteAnnounced(_) = htlc.state {
3608                                 return Err(ChannelError::Close("Got shutdown with remote pending HTLCs".to_owned()));
3609                         }
3610                 }
3611                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
3612
3613                 if !script::is_bolt2_compliant(&msg.scriptpubkey, their_features) {
3614                         return Err(ChannelError::Close(format!("Got a nonstandard scriptpubkey ({}) from remote peer", msg.scriptpubkey.to_bytes().to_hex())));
3615                 }
3616
3617                 if self.counterparty_shutdown_scriptpubkey.is_some() {
3618                         if Some(&msg.scriptpubkey) != self.counterparty_shutdown_scriptpubkey.as_ref() {
3619                                 return Err(ChannelError::Close(format!("Got shutdown request with a scriptpubkey ({}) which did not match their previous scriptpubkey.", msg.scriptpubkey.to_bytes().to_hex())));
3620                         }
3621                 } else {
3622                         self.counterparty_shutdown_scriptpubkey = Some(msg.scriptpubkey.clone());
3623                 }
3624
3625                 // If we have any LocalAnnounced updates we'll probably just get back an update_fail_htlc
3626                 // immediately after the commitment dance, but we can send a Shutdown because we won't send
3627                 // any further commitment updates after we set LocalShutdownSent.
3628                 let send_shutdown = (self.channel_state & ChannelState::LocalShutdownSent as u32) != ChannelState::LocalShutdownSent as u32;
3629
3630                 let update_shutdown_script = match self.shutdown_scriptpubkey {
3631                         Some(_) => false,
3632                         None => {
3633                                 assert!(send_shutdown);
3634                                 let shutdown_scriptpubkey = keys_provider.get_shutdown_scriptpubkey();
3635                                 if !shutdown_scriptpubkey.is_compatible(their_features) {
3636                                         return Err(ChannelError::Close(format!("Provided a scriptpubkey format not accepted by peer: {}", shutdown_scriptpubkey)));
3637                                 }
3638                                 self.shutdown_scriptpubkey = Some(shutdown_scriptpubkey);
3639                                 true
3640                         },
3641                 };
3642
3643                 // From here on out, we may not fail!
3644
3645                 self.channel_state |= ChannelState::RemoteShutdownSent as u32;
3646                 self.update_time_counter += 1;
3647
3648                 let monitor_update = if update_shutdown_script {
3649                         self.latest_monitor_update_id += 1;
3650                         Some(ChannelMonitorUpdate {
3651                                 update_id: self.latest_monitor_update_id,
3652                                 updates: vec![ChannelMonitorUpdateStep::ShutdownScript {
3653                                         scriptpubkey: self.get_closing_scriptpubkey(),
3654                                 }],
3655                         })
3656                 } else { None };
3657                 let shutdown = if send_shutdown {
3658                         Some(msgs::Shutdown {
3659                                 channel_id: self.channel_id,
3660                                 scriptpubkey: self.get_closing_scriptpubkey(),
3661                         })
3662                 } else { None };
3663
3664                 // We can't send our shutdown until we've committed all of our pending HTLCs, but the
3665                 // remote side is unlikely to accept any new HTLCs, so we go ahead and "free" any holding
3666                 // cell HTLCs and return them to fail the payment.
3667                 self.holding_cell_update_fee = None;
3668                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
3669                 self.holding_cell_htlc_updates.retain(|htlc_update| {
3670                         match htlc_update {
3671                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
3672                                         dropped_outbound_htlcs.push((source.clone(), payment_hash.clone()));
3673                                         false
3674                                 },
3675                                 _ => true
3676                         }
3677                 });
3678
3679                 self.channel_state |= ChannelState::LocalShutdownSent as u32;
3680                 self.update_time_counter += 1;
3681
3682                 Ok((shutdown, monitor_update, dropped_outbound_htlcs))
3683         }
3684
3685         fn build_signed_closing_transaction(&self, closing_tx: &ClosingTransaction, counterparty_sig: &Signature, sig: &Signature) -> Transaction {
3686                 let mut tx = closing_tx.trust().built_transaction().clone();
3687
3688                 tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
3689
3690                 let funding_key = self.get_holder_pubkeys().funding_pubkey.serialize();
3691                 let counterparty_funding_key = self.counterparty_funding_pubkey().serialize();
3692                 if funding_key[..] < counterparty_funding_key[..] {
3693                         tx.input[0].witness.push(sig.serialize_der().to_vec());
3694                         tx.input[0].witness.push(counterparty_sig.serialize_der().to_vec());
3695                 } else {
3696                         tx.input[0].witness.push(counterparty_sig.serialize_der().to_vec());
3697                         tx.input[0].witness.push(sig.serialize_der().to_vec());
3698                 }
3699                 tx.input[0].witness[1].push(SigHashType::All as u8);
3700                 tx.input[0].witness[2].push(SigHashType::All as u8);
3701
3702                 tx.input[0].witness.push(self.get_funding_redeemscript().into_bytes());
3703                 tx
3704         }
3705
3706         pub fn closing_signed<F: Deref>(&mut self, fee_estimator: &F, msg: &msgs::ClosingSigned) -> Result<(Option<msgs::ClosingSigned>, Option<Transaction>), ChannelError>
3707                 where F::Target: FeeEstimator
3708         {
3709                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != BOTH_SIDES_SHUTDOWN_MASK {
3710                         return Err(ChannelError::Close("Remote end sent us a closing_signed before both sides provided a shutdown".to_owned()));
3711                 }
3712                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
3713                         return Err(ChannelError::Close("Peer sent closing_signed when we needed a channel_reestablish".to_owned()));
3714                 }
3715                 if !self.pending_inbound_htlcs.is_empty() || !self.pending_outbound_htlcs.is_empty() {
3716                         return Err(ChannelError::Close("Remote end sent us a closing_signed while there were still pending HTLCs".to_owned()));
3717                 }
3718                 if msg.fee_satoshis > 21_000_000 * 1_0000_0000 { //this is required to stop potential overflow in build_closing_transaction
3719                         return Err(ChannelError::Close("Remote tried to send us a closing tx with > 21 million BTC fee".to_owned()));
3720                 }
3721
3722                 if self.is_outbound() && self.last_sent_closing_fee.is_none() {
3723                         return Err(ChannelError::Close("Remote tried to send a closing_signed when we were supposed to propose the first one".to_owned()));
3724                 }
3725
3726                 if self.channel_state & ChannelState::MonitorUpdateFailed as u32 != 0 {
3727                         self.pending_counterparty_closing_signed = Some(msg.clone());
3728                         return Ok((None, None));
3729                 }
3730
3731                 let funding_redeemscript = self.get_funding_redeemscript();
3732                 let (mut closing_tx, used_total_fee) = self.build_closing_transaction(msg.fee_satoshis, false);
3733                 if used_total_fee != msg.fee_satoshis {
3734                         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)));
3735                 }
3736                 let sighash = closing_tx.trust().get_sighash_all(&funding_redeemscript, self.channel_value_satoshis);
3737
3738                 match self.secp_ctx.verify(&sighash, &msg.signature, &self.get_counterparty_pubkeys().funding_pubkey) {
3739                         Ok(_) => {},
3740                         Err(_e) => {
3741                                 // The remote end may have decided to revoke their output due to inconsistent dust
3742                                 // limits, so check for that case by re-checking the signature here.
3743                                 closing_tx = self.build_closing_transaction(msg.fee_satoshis, true).0;
3744                                 let sighash = closing_tx.trust().get_sighash_all(&funding_redeemscript, self.channel_value_satoshis);
3745                                 secp_check!(self.secp_ctx.verify(&sighash, &msg.signature, self.counterparty_funding_pubkey()), "Invalid closing tx signature from peer".to_owned());
3746                         },
3747                 };
3748
3749                 for outp in closing_tx.trust().built_transaction().output.iter() {
3750                         if !outp.script_pubkey.is_witness_program() && outp.value < MAX_STD_OUTPUT_DUST_LIMIT_SATOSHIS {
3751                                 return Err(ChannelError::Close("Remote sent us a closing_signed with a dust output. Always use segwit closing scripts!".to_owned()));
3752                         }
3753                 }
3754
3755                 assert!(self.shutdown_scriptpubkey.is_some());
3756                 if let Some((last_fee, sig)) = self.last_sent_closing_fee {
3757                         if last_fee == msg.fee_satoshis {
3758                                 let tx = self.build_signed_closing_transaction(&mut closing_tx, &msg.signature, &sig);
3759                                 self.channel_state = ChannelState::ShutdownComplete as u32;
3760                                 self.update_time_counter += 1;
3761                                 return Ok((None, Some(tx)));
3762                         }
3763                 }
3764
3765                 let (our_min_fee, our_max_fee) = self.calculate_closing_fee_limits(fee_estimator);
3766
3767                 macro_rules! propose_fee {
3768                         ($new_fee: expr) => {
3769                                 let (closing_tx, used_fee) = if $new_fee == msg.fee_satoshis {
3770                                         (closing_tx, $new_fee)
3771                                 } else {
3772                                         self.build_closing_transaction($new_fee, false)
3773                                 };
3774
3775                                 let sig = self.holder_signer
3776                                         .sign_closing_transaction(&closing_tx, &self.secp_ctx)
3777                                         .map_err(|_| ChannelError::Close("External signer refused to sign closing transaction".to_owned()))?;
3778
3779                                 let signed_tx = if $new_fee == msg.fee_satoshis {
3780                                         self.channel_state = ChannelState::ShutdownComplete as u32;
3781                                         self.update_time_counter += 1;
3782                                         let tx = self.build_signed_closing_transaction(&closing_tx, &msg.signature, &sig);
3783                                         Some(tx)
3784                                 } else { None };
3785
3786                                 self.last_sent_closing_fee = Some((used_fee, sig.clone()));
3787                                 return Ok((Some(msgs::ClosingSigned {
3788                                         channel_id: self.channel_id,
3789                                         fee_satoshis: used_fee,
3790                                         signature: sig,
3791                                         fee_range: Some(msgs::ClosingSignedFeeRange {
3792                                                 min_fee_satoshis: our_min_fee,
3793                                                 max_fee_satoshis: our_max_fee,
3794                                         }),
3795                                 }), signed_tx))
3796                         }
3797                 }
3798
3799                 if let Some(msgs::ClosingSignedFeeRange { min_fee_satoshis, max_fee_satoshis }) = msg.fee_range {
3800                         if msg.fee_satoshis < min_fee_satoshis || msg.fee_satoshis > max_fee_satoshis {
3801                                 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)));
3802                         }
3803                         if max_fee_satoshis < our_min_fee {
3804                                 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)));
3805                         }
3806                         if min_fee_satoshis > our_max_fee {
3807                                 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)));
3808                         }
3809
3810                         if !self.is_outbound() {
3811                                 // They have to pay, so pick the highest fee in the overlapping range.
3812                                 // We should never set an upper bound aside from their full balance
3813                                 debug_assert_eq!(our_max_fee, self.channel_value_satoshis - (self.value_to_self_msat + 999) / 1000);
3814                                 propose_fee!(cmp::min(max_fee_satoshis, our_max_fee));
3815                         } else {
3816                                 if msg.fee_satoshis < our_min_fee || msg.fee_satoshis > our_max_fee {
3817                                         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.",
3818                                                 msg.fee_satoshis, our_min_fee, our_max_fee)));
3819                                 }
3820                                 // The proposed fee is in our acceptable range, accept it and broadcast!
3821                                 propose_fee!(msg.fee_satoshis);
3822                         }
3823                 } else {
3824                         // Old fee style negotiation. We don't bother to enforce whether they are complying
3825                         // with the "making progress" requirements, we just comply and hope for the best.
3826                         if let Some((last_fee, _)) = self.last_sent_closing_fee {
3827                                 if msg.fee_satoshis > last_fee {
3828                                         if msg.fee_satoshis < our_max_fee {
3829                                                 propose_fee!(msg.fee_satoshis);
3830                                         } else if last_fee < our_max_fee {
3831                                                 propose_fee!(our_max_fee);
3832                                         } else {
3833                                                 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)));
3834                                         }
3835                                 } else {
3836                                         if msg.fee_satoshis > our_min_fee {
3837                                                 propose_fee!(msg.fee_satoshis);
3838                                         } else if last_fee > our_min_fee {
3839                                                 propose_fee!(our_min_fee);
3840                                         } else {
3841                                                 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)));
3842                                         }
3843                                 }
3844                         } else {
3845                                 if msg.fee_satoshis < our_min_fee {
3846                                         propose_fee!(our_min_fee);
3847                                 } else if msg.fee_satoshis > our_max_fee {
3848                                         propose_fee!(our_max_fee);
3849                                 } else {
3850                                         propose_fee!(msg.fee_satoshis);
3851                                 }
3852                         }
3853                 }
3854         }
3855
3856         // Public utilities:
3857
3858         pub fn channel_id(&self) -> [u8; 32] {
3859                 self.channel_id
3860         }
3861
3862         pub fn minimum_depth(&self) -> Option<u32> {
3863                 self.minimum_depth
3864         }
3865
3866         /// Gets the "user_id" value passed into the construction of this channel. It has no special
3867         /// meaning and exists only to allow users to have a persistent identifier of a channel.
3868         pub fn get_user_id(&self) -> u64 {
3869                 self.user_id
3870         }
3871
3872         /// Guaranteed to be Some after both FundingLocked messages have been exchanged (and, thus,
3873         /// is_usable() returns true).
3874         /// Allowed in any state (including after shutdown)
3875         pub fn get_short_channel_id(&self) -> Option<u64> {
3876                 self.short_channel_id
3877         }
3878
3879         /// Returns the funding_txo we either got from our peer, or were given by
3880         /// get_outbound_funding_created.
3881         pub fn get_funding_txo(&self) -> Option<OutPoint> {
3882                 self.channel_transaction_parameters.funding_outpoint
3883         }
3884
3885         fn get_holder_selected_contest_delay(&self) -> u16 {
3886                 self.channel_transaction_parameters.holder_selected_contest_delay
3887         }
3888
3889         fn get_holder_pubkeys(&self) -> &ChannelPublicKeys {
3890                 &self.channel_transaction_parameters.holder_pubkeys
3891         }
3892
3893         pub fn get_counterparty_selected_contest_delay(&self) -> Option<u16> {
3894                 self.channel_transaction_parameters.counterparty_parameters
3895                         .as_ref().map(|params| params.selected_contest_delay)
3896         }
3897
3898         fn get_counterparty_pubkeys(&self) -> &ChannelPublicKeys {
3899                 &self.channel_transaction_parameters.counterparty_parameters.as_ref().unwrap().pubkeys
3900         }
3901
3902         /// Allowed in any state (including after shutdown)
3903         pub fn get_counterparty_node_id(&self) -> PublicKey {
3904                 self.counterparty_node_id
3905         }
3906
3907         /// Allowed in any state (including after shutdown)
3908         #[cfg(test)]
3909         pub fn get_holder_htlc_minimum_msat(&self) -> u64 {
3910                 self.holder_htlc_minimum_msat
3911         }
3912
3913         /// Allowed in any state (including after shutdown)
3914         pub fn get_announced_htlc_max_msat(&self) -> u64 {
3915                 return cmp::min(
3916                         // Upper bound by capacity. We make it a bit less than full capacity to prevent attempts
3917                         // to use full capacity. This is an effort to reduce routing failures, because in many cases
3918                         // channel might have been used to route very small values (either by honest users or as DoS).
3919                         self.channel_value_satoshis * 1000 * 9 / 10,
3920
3921                         Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis)
3922                 );
3923         }
3924
3925         /// Allowed in any state (including after shutdown)
3926         pub fn get_counterparty_htlc_minimum_msat(&self) -> u64 {
3927                 self.counterparty_htlc_minimum_msat
3928         }
3929
3930         pub fn get_value_satoshis(&self) -> u64 {
3931                 self.channel_value_satoshis
3932         }
3933
3934         pub fn get_fee_proportional_millionths(&self) -> u32 {
3935                 self.config.forwarding_fee_proportional_millionths
3936         }
3937
3938         pub fn get_cltv_expiry_delta(&self) -> u16 {
3939                 cmp::max(self.config.cltv_expiry_delta, MIN_CLTV_EXPIRY_DELTA)
3940         }
3941
3942         pub fn get_max_dust_htlc_exposure_msat(&self) -> u64 {
3943                 self.config.max_dust_htlc_exposure_msat
3944         }
3945
3946         pub fn get_feerate(&self) -> u32 {
3947                 self.feerate_per_kw
3948         }
3949
3950         pub fn get_dust_buffer_feerate(&self) -> u32 {
3951                 // When calculating our exposure to dust HTLCs, we assume that the channel feerate
3952                 // may, at any point, increase by at least 10 sat/vB (i.e 2530 sat/kWU) or 25%,
3953                 // whichever is higher. This ensures that we aren't suddenly exposed to significantly
3954                 // more dust balance if the feerate increases when we have several HTLCs pending
3955                 // which are near the dust limit.
3956                 let mut feerate_per_kw = self.feerate_per_kw;
3957                 // If there's a pending update fee, use it to ensure we aren't under-estimating
3958                 // potential feerate updates coming soon.
3959                 if let Some((feerate, _)) = self.pending_update_fee {
3960                         feerate_per_kw = cmp::max(feerate_per_kw, feerate);
3961                 }
3962                 cmp::max(2530, feerate_per_kw * 1250 / 1000)
3963         }
3964
3965         pub fn get_cur_holder_commitment_transaction_number(&self) -> u64 {
3966                 self.cur_holder_commitment_transaction_number + 1
3967         }
3968
3969         pub fn get_cur_counterparty_commitment_transaction_number(&self) -> u64 {
3970                 self.cur_counterparty_commitment_transaction_number + 1 - if self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32) != 0 { 1 } else { 0 }
3971         }
3972
3973         pub fn get_revoked_counterparty_commitment_transaction_number(&self) -> u64 {
3974                 self.cur_counterparty_commitment_transaction_number + 2
3975         }
3976
3977         #[cfg(test)]
3978         pub fn get_signer(&self) -> &Signer {
3979                 &self.holder_signer
3980         }
3981
3982         #[cfg(test)]
3983         pub fn get_value_stat(&self) -> ChannelValueStat {
3984                 ChannelValueStat {
3985                         value_to_self_msat: self.value_to_self_msat,
3986                         channel_value_msat: self.channel_value_satoshis * 1000,
3987                         channel_reserve_msat: self.counterparty_selected_channel_reserve_satoshis.unwrap() * 1000,
3988                         pending_outbound_htlcs_amount_msat: self.pending_outbound_htlcs.iter().map(|ref h| h.amount_msat).sum::<u64>(),
3989                         pending_inbound_htlcs_amount_msat: self.pending_inbound_htlcs.iter().map(|ref h| h.amount_msat).sum::<u64>(),
3990                         holding_cell_outbound_amount_msat: {
3991                                 let mut res = 0;
3992                                 for h in self.holding_cell_htlc_updates.iter() {
3993                                         match h {
3994                                                 &HTLCUpdateAwaitingACK::AddHTLC{amount_msat, .. } => {
3995                                                         res += amount_msat;
3996                                                 }
3997                                                 _ => {}
3998                                         }
3999                                 }
4000                                 res
4001                         },
4002                         counterparty_max_htlc_value_in_flight_msat: self.counterparty_max_htlc_value_in_flight_msat,
4003                         counterparty_dust_limit_msat: self.counterparty_dust_limit_satoshis * 1000,
4004                 }
4005         }
4006
4007         /// Allowed in any state (including after shutdown)
4008         pub fn get_update_time_counter(&self) -> u32 {
4009                 self.update_time_counter
4010         }
4011
4012         pub fn get_latest_monitor_update_id(&self) -> u64 {
4013                 self.latest_monitor_update_id
4014         }
4015
4016         pub fn should_announce(&self) -> bool {
4017                 self.config.announced_channel
4018         }
4019
4020         pub fn is_outbound(&self) -> bool {
4021                 self.channel_transaction_parameters.is_outbound_from_holder
4022         }
4023
4024         /// Gets the fee we'd want to charge for adding an HTLC output to this Channel
4025         /// Allowed in any state (including after shutdown)
4026         pub fn get_outbound_forwarding_fee_base_msat(&self) -> u32 {
4027                 self.config.forwarding_fee_base_msat
4028         }
4029
4030         /// Returns true if we've ever received a message from the remote end for this Channel
4031         pub fn have_received_message(&self) -> bool {
4032                 self.channel_state > (ChannelState::OurInitSent as u32)
4033         }
4034
4035         /// Returns true if this channel is fully established and not known to be closing.
4036         /// Allowed in any state (including after shutdown)
4037         pub fn is_usable(&self) -> bool {
4038                 let mask = ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK;
4039                 (self.channel_state & mask) == (ChannelState::ChannelFunded as u32)
4040         }
4041
4042         /// Returns true if this channel is currently available for use. This is a superset of
4043         /// is_usable() and considers things like the channel being temporarily disabled.
4044         /// Allowed in any state (including after shutdown)
4045         pub fn is_live(&self) -> bool {
4046                 self.is_usable() && (self.channel_state & (ChannelState::PeerDisconnected as u32) == 0)
4047         }
4048
4049         /// Returns true if this channel has been marked as awaiting a monitor update to move forward.
4050         /// Allowed in any state (including after shutdown)
4051         pub fn is_awaiting_monitor_update(&self) -> bool {
4052                 (self.channel_state & ChannelState::MonitorUpdateFailed as u32) != 0
4053         }
4054
4055         /// Returns true if funding_created was sent/received.
4056         pub fn is_funding_initiated(&self) -> bool {
4057                 self.channel_state >= ChannelState::FundingSent as u32
4058         }
4059
4060         /// Returns true if our peer has either initiated or agreed to shut down the channel.
4061         pub fn received_shutdown(&self) -> bool {
4062                 (self.channel_state & ChannelState::RemoteShutdownSent as u32) != 0
4063         }
4064
4065         /// Returns true if we either initiated or agreed to shut down the channel.
4066         pub fn sent_shutdown(&self) -> bool {
4067                 (self.channel_state & ChannelState::LocalShutdownSent as u32) != 0
4068         }
4069
4070         /// Returns true if this channel is fully shut down. True here implies that no further actions
4071         /// may/will be taken on this channel, and thus this object should be freed. Any future changes
4072         /// will be handled appropriately by the chain monitor.
4073         pub fn is_shutdown(&self) -> bool {
4074                 if (self.channel_state & ChannelState::ShutdownComplete as u32) == ChannelState::ShutdownComplete as u32  {
4075                         assert!(self.channel_state == ChannelState::ShutdownComplete as u32);
4076                         true
4077                 } else { false }
4078         }
4079
4080         pub fn channel_update_status(&self) -> ChannelUpdateStatus {
4081                 self.channel_update_status
4082         }
4083
4084         pub fn set_channel_update_status(&mut self, status: ChannelUpdateStatus) {
4085                 self.channel_update_status = status;
4086         }
4087
4088         fn check_get_funding_locked(&mut self, height: u32) -> Option<msgs::FundingLocked> {
4089                 if self.funding_tx_confirmation_height == 0 {
4090                         return None;
4091                 }
4092
4093                 let funding_tx_confirmations = height as i64 - self.funding_tx_confirmation_height as i64 + 1;
4094                 if funding_tx_confirmations <= 0 {
4095                         self.funding_tx_confirmation_height = 0;
4096                 }
4097
4098                 if funding_tx_confirmations < self.minimum_depth.unwrap_or(0) as i64 {
4099                         return None;
4100                 }
4101
4102                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
4103                 let need_commitment_update = if non_shutdown_state == ChannelState::FundingSent as u32 {
4104                         self.channel_state |= ChannelState::OurFundingLocked as u32;
4105                         true
4106                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32) {
4107                         self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
4108                         self.update_time_counter += 1;
4109                         true
4110                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) {
4111                         // We got a reorg but not enough to trigger a force close, just ignore.
4112                         false
4113                 } else if self.channel_state < ChannelState::ChannelFunded as u32 {
4114                         panic!("Started confirming a channel in a state pre-FundingSent?: {}", self.channel_state);
4115                 } else {
4116                         // We got a reorg but not enough to trigger a force close, just ignore.
4117                         false
4118                 };
4119
4120                 if need_commitment_update {
4121                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) == 0 {
4122                                 let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
4123                                 return Some(msgs::FundingLocked {
4124                                         channel_id: self.channel_id,
4125                                         next_per_commitment_point,
4126                                 });
4127                         } else {
4128                                 self.monitor_pending_funding_locked = true;
4129                         }
4130                 }
4131                 None
4132         }
4133
4134         /// When a transaction is confirmed, we check whether it is or spends the funding transaction
4135         /// In the first case, we store the confirmation height and calculating the short channel id.
4136         /// In the second, we simply return an Err indicating we need to be force-closed now.
4137         pub fn transactions_confirmed<L: Deref>(&mut self, block_hash: &BlockHash, height: u32, txdata: &TransactionData, logger: &L)
4138         -> Result<Option<msgs::FundingLocked>, ClosureReason> where L::Target: Logger {
4139                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
4140                 for &(index_in_block, tx) in txdata.iter() {
4141                         if let Some(funding_txo) = self.get_funding_txo() {
4142                                 // If we haven't yet sent a funding_locked, but are in FundingSent (ignoring
4143                                 // whether they've sent a funding_locked or not), check if we should send one.
4144                                 if non_shutdown_state & !(ChannelState::TheirFundingLocked as u32) == ChannelState::FundingSent as u32 {
4145                                         if tx.txid() == funding_txo.txid {
4146                                                 let txo_idx = funding_txo.index as usize;
4147                                                 if txo_idx >= tx.output.len() || tx.output[txo_idx].script_pubkey != self.get_funding_redeemscript().to_v0_p2wsh() ||
4148                                                                 tx.output[txo_idx].value != self.channel_value_satoshis {
4149                                                         if self.is_outbound() {
4150                                                                 // If we generated the funding transaction and it doesn't match what it
4151                                                                 // should, the client is really broken and we should just panic and
4152                                                                 // tell them off. That said, because hash collisions happen with high
4153                                                                 // probability in fuzztarget mode, if we're fuzzing we just close the
4154                                                                 // channel and move on.
4155                                                                 #[cfg(not(feature = "fuzztarget"))]
4156                                                                 panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
4157                                                         }
4158                                                         self.update_time_counter += 1;
4159                                                         let err_reason = "funding tx had wrong script/value or output index";
4160                                                         return Err(ClosureReason::ProcessingError { err: err_reason.to_owned() });
4161                                                 } else {
4162                                                         if self.is_outbound() {
4163                                                                 for input in tx.input.iter() {
4164                                                                         if input.witness.is_empty() {
4165                                                                                 // We generated a malleable funding transaction, implying we've
4166                                                                                 // just exposed ourselves to funds loss to our counterparty.
4167                                                                                 #[cfg(not(feature = "fuzztarget"))]
4168                                                                                 panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
4169                                                                         }
4170                                                                 }
4171                                                         }
4172                                                         self.funding_tx_confirmation_height = height;
4173                                                         self.funding_tx_confirmed_in = Some(*block_hash);
4174                                                         self.short_channel_id = match scid_from_parts(height as u64, index_in_block as u64, txo_idx as u64) {
4175                                                                 Ok(scid) => Some(scid),
4176                                                                 Err(_) => panic!("Block was bogus - either height was > 16 million, had > 16 million transactions, or had > 65k outputs"),
4177                                                         }
4178                                                 }
4179                                         }
4180                                         // If we allow 1-conf funding, we may need to check for funding_locked here and
4181                                         // send it immediately instead of waiting for a best_block_updated call (which
4182                                         // may have already happened for this block).
4183                                         if let Some(funding_locked) = self.check_get_funding_locked(height) {
4184                                                 log_info!(logger, "Sending a funding_locked to our peer for channel {}", log_bytes!(self.channel_id));
4185                                                 return Ok(Some(funding_locked));
4186                                         }
4187                                 }
4188                                 for inp in tx.input.iter() {
4189                                         if inp.previous_output == funding_txo.into_bitcoin_outpoint() {
4190                                                 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()));
4191                                                 return Err(ClosureReason::CommitmentTxConfirmed);
4192                                         }
4193                                 }
4194                         }
4195                 }
4196                 Ok(None)
4197         }
4198
4199         /// When a new block is connected, we check the height of the block against outbound holding
4200         /// cell HTLCs in case we need to give up on them prematurely and time them out. Everything
4201         /// else (e.g. commitment transaction broadcasts, HTLC transaction broadcasting, etc) is
4202         /// handled by the ChannelMonitor.
4203         ///
4204         /// If we return Err, the channel may have been closed, at which point the standard
4205         /// requirements apply - no calls may be made except those explicitly stated to be allowed
4206         /// post-shutdown.
4207         ///
4208         /// May return some HTLCs (and their payment_hash) which have timed out and should be failed
4209         /// back.
4210         pub fn best_block_updated<L: Deref>(&mut self, height: u32, highest_header_time: u32, logger: &L)
4211         -> Result<(Option<msgs::FundingLocked>, Vec<(HTLCSource, PaymentHash)>), ClosureReason> where L::Target: Logger {
4212                 let mut timed_out_htlcs = Vec::new();
4213                 // This mirrors the check in ChannelManager::decode_update_add_htlc_onion, refusing to
4214                 // forward an HTLC when our counterparty should almost certainly just fail it for expiring
4215                 // ~now.
4216                 let unforwarded_htlc_cltv_limit = height + LATENCY_GRACE_PERIOD_BLOCKS;
4217                 self.holding_cell_htlc_updates.retain(|htlc_update| {
4218                         match htlc_update {
4219                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, ref cltv_expiry, .. } => {
4220                                         if *cltv_expiry <= unforwarded_htlc_cltv_limit {
4221                                                 timed_out_htlcs.push((source.clone(), payment_hash.clone()));
4222                                                 false
4223                                         } else { true }
4224                                 },
4225                                 _ => true
4226                         }
4227                 });
4228
4229                 self.update_time_counter = cmp::max(self.update_time_counter, highest_header_time);
4230
4231                 if let Some(funding_locked) = self.check_get_funding_locked(height) {
4232                         log_info!(logger, "Sending a funding_locked to our peer for channel {}", log_bytes!(self.channel_id));
4233                         return Ok((Some(funding_locked), timed_out_htlcs));
4234                 }
4235
4236                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
4237                 if non_shutdown_state >= ChannelState::ChannelFunded as u32 ||
4238                    (non_shutdown_state & ChannelState::OurFundingLocked as u32) == ChannelState::OurFundingLocked as u32 {
4239                         let mut funding_tx_confirmations = height as i64 - self.funding_tx_confirmation_height as i64 + 1;
4240                         if self.funding_tx_confirmation_height == 0 {
4241                                 // Note that check_get_funding_locked may reset funding_tx_confirmation_height to
4242                                 // zero if it has been reorged out, however in either case, our state flags
4243                                 // indicate we've already sent a funding_locked
4244                                 funding_tx_confirmations = 0;
4245                         }
4246
4247                         // If we've sent funding_locked (or have both sent and received funding_locked), and
4248                         // the funding transaction's confirmation count has dipped below minimum_depth / 2,
4249                         // close the channel and hope we can get the latest state on chain (because presumably
4250                         // the funding transaction is at least still in the mempool of most nodes).
4251                         if funding_tx_confirmations < self.minimum_depth.unwrap() as i64 / 2 {
4252                                 let err_reason = format!("Funding transaction was un-confirmed. Locked at {} confs, now have {} confs.",
4253                                         self.minimum_depth.unwrap(), funding_tx_confirmations);
4254                                 return Err(ClosureReason::ProcessingError { err: err_reason });
4255                         }
4256                 } else if !self.is_outbound() && self.funding_tx_confirmed_in.is_none() &&
4257                                 height >= self.channel_creation_height + FUNDING_CONF_DEADLINE_BLOCKS {
4258                         log_info!(logger, "Closing channel {} due to funding timeout", log_bytes!(self.channel_id));
4259                         // If funding_tx_confirmed_in is unset, the channel must not be active
4260                         assert!(non_shutdown_state <= ChannelState::ChannelFunded as u32);
4261                         assert_eq!(non_shutdown_state & ChannelState::OurFundingLocked as u32, 0);
4262                         return Err(ClosureReason::FundingTimedOut);
4263                 }
4264
4265                 Ok((None, timed_out_htlcs))
4266         }
4267
4268         /// Indicates the funding transaction is no longer confirmed in the main chain. This may
4269         /// force-close the channel, but may also indicate a harmless reorganization of a block or two
4270         /// before the channel has reached funding_locked and we can just wait for more blocks.
4271         pub fn funding_transaction_unconfirmed<L: Deref>(&mut self, logger: &L) -> Result<(), ClosureReason> where L::Target: Logger {
4272                 if self.funding_tx_confirmation_height != 0 {
4273                         // We handle the funding disconnection by calling best_block_updated with a height one
4274                         // below where our funding was connected, implying a reorg back to conf_height - 1.
4275                         let reorg_height = self.funding_tx_confirmation_height - 1;
4276                         // We use the time field to bump the current time we set on channel updates if its
4277                         // larger. If we don't know that time has moved forward, we can just set it to the last
4278                         // time we saw and it will be ignored.
4279                         let best_time = self.update_time_counter;
4280                         match self.best_block_updated(reorg_height, best_time, logger) {
4281                                 Ok((funding_locked, timed_out_htlcs)) => {
4282                                         assert!(funding_locked.is_none(), "We can't generate a funding with 0 confirmations?");
4283                                         assert!(timed_out_htlcs.is_empty(), "We can't have accepted HTLCs with a timeout before our funding confirmation?");
4284                                         Ok(())
4285                                 },
4286                                 Err(e) => Err(e)
4287                         }
4288                 } else {
4289                         // We never learned about the funding confirmation anyway, just ignore
4290                         Ok(())
4291                 }
4292         }
4293
4294         // Methods to get unprompted messages to send to the remote end (or where we already returned
4295         // something in the handler for the message that prompted this message):
4296
4297         pub fn get_open_channel(&self, chain_hash: BlockHash) -> msgs::OpenChannel {
4298                 if !self.is_outbound() {
4299                         panic!("Tried to open a channel for an inbound channel?");
4300                 }
4301                 if self.channel_state != ChannelState::OurInitSent as u32 {
4302                         panic!("Cannot generate an open_channel after we've moved forward");
4303                 }
4304
4305                 if self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
4306                         panic!("Tried to send an open_channel for a channel that has already advanced");
4307                 }
4308
4309                 let first_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
4310                 let keys = self.get_holder_pubkeys();
4311
4312                 msgs::OpenChannel {
4313                         chain_hash,
4314                         temporary_channel_id: self.channel_id,
4315                         funding_satoshis: self.channel_value_satoshis,
4316                         push_msat: self.channel_value_satoshis * 1000 - self.value_to_self_msat,
4317                         dust_limit_satoshis: self.holder_dust_limit_satoshis,
4318                         max_htlc_value_in_flight_msat: Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis),
4319                         channel_reserve_satoshis: Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis),
4320                         htlc_minimum_msat: self.holder_htlc_minimum_msat,
4321                         feerate_per_kw: self.feerate_per_kw as u32,
4322                         to_self_delay: self.get_holder_selected_contest_delay(),
4323                         max_accepted_htlcs: OUR_MAX_HTLCS,
4324                         funding_pubkey: keys.funding_pubkey,
4325                         revocation_basepoint: keys.revocation_basepoint,
4326                         payment_point: keys.payment_point,
4327                         delayed_payment_basepoint: keys.delayed_payment_basepoint,
4328                         htlc_basepoint: keys.htlc_basepoint,
4329                         first_per_commitment_point,
4330                         channel_flags: if self.config.announced_channel {1} else {0},
4331                         shutdown_scriptpubkey: OptionalField::Present(match &self.shutdown_scriptpubkey {
4332                                 Some(script) => script.clone().into_inner(),
4333                                 None => Builder::new().into_script(),
4334                         }),
4335                         channel_type: Some(self.channel_type.clone()),
4336                 }
4337         }
4338
4339         pub fn get_accept_channel(&self) -> msgs::AcceptChannel {
4340                 if self.is_outbound() {
4341                         panic!("Tried to send accept_channel for an outbound channel?");
4342                 }
4343                 if self.channel_state != (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32) {
4344                         panic!("Tried to send accept_channel after channel had moved forward");
4345                 }
4346                 if self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
4347                         panic!("Tried to send an accept_channel for a channel that has already advanced");
4348                 }
4349
4350                 let first_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
4351                 let keys = self.get_holder_pubkeys();
4352
4353                 msgs::AcceptChannel {
4354                         temporary_channel_id: self.channel_id,
4355                         dust_limit_satoshis: self.holder_dust_limit_satoshis,
4356                         max_htlc_value_in_flight_msat: Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis),
4357                         channel_reserve_satoshis: Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis),
4358                         htlc_minimum_msat: self.holder_htlc_minimum_msat,
4359                         minimum_depth: self.minimum_depth.unwrap(),
4360                         to_self_delay: self.get_holder_selected_contest_delay(),
4361                         max_accepted_htlcs: OUR_MAX_HTLCS,
4362                         funding_pubkey: keys.funding_pubkey,
4363                         revocation_basepoint: keys.revocation_basepoint,
4364                         payment_point: keys.payment_point,
4365                         delayed_payment_basepoint: keys.delayed_payment_basepoint,
4366                         htlc_basepoint: keys.htlc_basepoint,
4367                         first_per_commitment_point,
4368                         shutdown_scriptpubkey: OptionalField::Present(match &self.shutdown_scriptpubkey {
4369                                 Some(script) => script.clone().into_inner(),
4370                                 None => Builder::new().into_script(),
4371                         }),
4372                 }
4373         }
4374
4375         /// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
4376         fn get_outbound_funding_created_signature<L: Deref>(&mut self, logger: &L) -> Result<Signature, ChannelError> where L::Target: Logger {
4377                 let counterparty_keys = self.build_remote_transaction_keys()?;
4378                 let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).0;
4379                 Ok(self.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, &self.secp_ctx)
4380                                 .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0)
4381         }
4382
4383         /// Updates channel state with knowledge of the funding transaction's txid/index, and generates
4384         /// a funding_created message for the remote peer.
4385         /// Panics if called at some time other than immediately after initial handshake, if called twice,
4386         /// or if called on an inbound channel.
4387         /// Note that channel_id changes during this call!
4388         /// Do NOT broadcast the funding transaction until after a successful funding_signed call!
4389         /// If an Err is returned, it is a ChannelError::Close.
4390         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 {
4391                 if !self.is_outbound() {
4392                         panic!("Tried to create outbound funding_created message on an inbound channel!");
4393                 }
4394                 if self.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
4395                         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)");
4396                 }
4397                 if self.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
4398                                 self.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
4399                                 self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
4400                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
4401                 }
4402
4403                 self.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
4404                 self.holder_signer.ready_channel(&self.channel_transaction_parameters);
4405
4406                 let signature = match self.get_outbound_funding_created_signature(logger) {
4407                         Ok(res) => res,
4408                         Err(e) => {
4409                                 log_error!(logger, "Got bad signatures: {:?}!", e);
4410                                 self.channel_transaction_parameters.funding_outpoint = None;
4411                                 return Err(e);
4412                         }
4413                 };
4414
4415                 let temporary_channel_id = self.channel_id;
4416
4417                 // Now that we're past error-generating stuff, update our local state:
4418
4419                 self.channel_state = ChannelState::FundingCreated as u32;
4420                 self.channel_id = funding_txo.to_channel_id();
4421                 self.funding_transaction = Some(funding_transaction);
4422
4423                 Ok(msgs::FundingCreated {
4424                         temporary_channel_id,
4425                         funding_txid: funding_txo.txid,
4426                         funding_output_index: funding_txo.index,
4427                         signature
4428                 })
4429         }
4430
4431         /// Gets an UnsignedChannelAnnouncement, as well as a signature covering it using our
4432         /// bitcoin_key, if available, for this channel. The channel must be publicly announceable and
4433         /// available for use (have exchanged FundingLocked messages in both directions). Should be used
4434         /// for both loose and in response to an AnnouncementSignatures message from the remote peer.
4435         /// Will only fail if we're not in a state where channel_announcement may be sent (including
4436         /// closing).
4437         /// Note that the "channel must be funded" requirement is stricter than BOLT 7 requires - see
4438         /// https://github.com/lightningnetwork/lightning-rfc/issues/468
4439         ///
4440         /// This will only return ChannelError::Ignore upon failure.
4441         pub fn get_channel_announcement(&self, node_id: PublicKey, chain_hash: BlockHash) -> Result<(msgs::UnsignedChannelAnnouncement, Signature), ChannelError> {
4442                 if !self.config.announced_channel {
4443                         return Err(ChannelError::Ignore("Channel is not available for public announcements".to_owned()));
4444                 }
4445                 if self.channel_state & (ChannelState::ChannelFunded as u32) == 0 {
4446                         return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement until the channel funding has been locked".to_owned()));
4447                 }
4448                 if (self.channel_state & (ChannelState::LocalShutdownSent as u32 | ChannelState::ShutdownComplete as u32)) != 0 {
4449                         return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement once the channel is closing".to_owned()));
4450                 }
4451
4452                 let were_node_one = node_id.serialize()[..] < self.counterparty_node_id.serialize()[..];
4453
4454                 let msg = msgs::UnsignedChannelAnnouncement {
4455                         features: ChannelFeatures::known(),
4456                         chain_hash,
4457                         short_channel_id: self.get_short_channel_id().unwrap(),
4458                         node_id_1: if were_node_one { node_id } else { self.get_counterparty_node_id() },
4459                         node_id_2: if were_node_one { self.get_counterparty_node_id() } else { node_id },
4460                         bitcoin_key_1: if were_node_one { self.get_holder_pubkeys().funding_pubkey } else { self.counterparty_funding_pubkey().clone() },
4461                         bitcoin_key_2: if were_node_one { self.counterparty_funding_pubkey().clone() } else { self.get_holder_pubkeys().funding_pubkey },
4462                         excess_data: Vec::new(),
4463                 };
4464
4465                 let sig = self.holder_signer.sign_channel_announcement(&msg, &self.secp_ctx)
4466                         .map_err(|_| ChannelError::Ignore("Signer rejected channel_announcement".to_owned()))?;
4467
4468                 Ok((msg, sig))
4469         }
4470
4471         /// Signs the given channel announcement, returning a ChannelError::Ignore if no keys are
4472         /// available.
4473         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> {
4474                 if let Some((their_node_sig, their_bitcoin_sig)) = self.announcement_sigs {
4475                         let were_node_one = announcement.node_id_1 == our_node_id;
4476
4477                         let our_node_sig = self.secp_ctx.sign(&msghash, our_node_secret);
4478                         Ok(msgs::ChannelAnnouncement {
4479                                 node_signature_1: if were_node_one { our_node_sig } else { their_node_sig },
4480                                 node_signature_2: if were_node_one { their_node_sig } else { our_node_sig },
4481                                 bitcoin_signature_1: if were_node_one { our_bitcoin_sig } else { their_bitcoin_sig },
4482                                 bitcoin_signature_2: if were_node_one { their_bitcoin_sig } else { our_bitcoin_sig },
4483                                 contents: announcement,
4484                         })
4485                 } else {
4486                         Err(ChannelError::Ignore("Attempted to sign channel announcement before we'd received announcement_signatures".to_string()))
4487                 }
4488         }
4489
4490         /// Processes an incoming announcement_signatures message, providing a fully-signed
4491         /// channel_announcement message which we can broadcast and storing our counterparty's
4492         /// signatures for later reconstruction/rebroadcast of the channel_announcement.
4493         pub fn announcement_signatures(&mut self, our_node_secret: &SecretKey, our_node_id: PublicKey, chain_hash: BlockHash, msg: &msgs::AnnouncementSignatures) -> Result<msgs::ChannelAnnouncement, ChannelError> {
4494                 let (announcement, our_bitcoin_sig) = self.get_channel_announcement(our_node_id.clone(), chain_hash)?;
4495
4496                 let msghash = hash_to_message!(&Sha256d::hash(&announcement.encode()[..])[..]);
4497
4498                 if self.secp_ctx.verify(&msghash, &msg.node_signature, &self.get_counterparty_node_id()).is_err() {
4499                         return Err(ChannelError::Close(format!(
4500                                 "Bad announcement_signatures. Failed to verify node_signature. UnsignedChannelAnnouncement used for verification is {:?}. their_node_key is {:?}",
4501                                  &announcement, self.get_counterparty_node_id())));
4502                 }
4503                 if self.secp_ctx.verify(&msghash, &msg.bitcoin_signature, self.counterparty_funding_pubkey()).is_err() {
4504                         return Err(ChannelError::Close(format!(
4505                                 "Bad announcement_signatures. Failed to verify bitcoin_signature. UnsignedChannelAnnouncement used for verification is {:?}. their_bitcoin_key is ({:?})",
4506                                 &announcement, self.counterparty_funding_pubkey())));
4507                 }
4508
4509                 self.announcement_sigs = Some((msg.node_signature, msg.bitcoin_signature));
4510
4511                 self.sign_channel_announcement(our_node_secret, our_node_id, msghash, announcement, our_bitcoin_sig)
4512         }
4513
4514         /// Gets a signed channel_announcement for this channel, if we previously received an
4515         /// announcement_signatures from our counterparty.
4516         pub fn get_signed_channel_announcement(&self, our_node_secret: &SecretKey, our_node_id: PublicKey, chain_hash: BlockHash) -> Option<msgs::ChannelAnnouncement> {
4517                 let (announcement, our_bitcoin_sig) = match self.get_channel_announcement(our_node_id.clone(), chain_hash) {
4518                         Ok(res) => res,
4519                         Err(_) => return None,
4520                 };
4521                 let msghash = hash_to_message!(&Sha256d::hash(&announcement.encode()[..])[..]);
4522                 match self.sign_channel_announcement(our_node_secret, our_node_id, msghash, announcement, our_bitcoin_sig) {
4523                         Ok(res) => Some(res),
4524                         Err(_) => None,
4525                 }
4526         }
4527
4528         /// May panic if called on a channel that wasn't immediately-previously
4529         /// self.remove_uncommitted_htlcs_and_mark_paused()'d
4530         pub fn get_channel_reestablish<L: Deref>(&self, logger: &L) -> msgs::ChannelReestablish where L::Target: Logger {
4531                 assert_eq!(self.channel_state & ChannelState::PeerDisconnected as u32, ChannelState::PeerDisconnected as u32);
4532                 assert_ne!(self.cur_counterparty_commitment_transaction_number, INITIAL_COMMITMENT_NUMBER);
4533                 // Prior to static_remotekey, my_current_per_commitment_point was critical to claiming
4534                 // current to_remote balances. However, it no longer has any use, and thus is now simply
4535                 // set to a dummy (but valid, as required by the spec) public key.
4536                 // fuzztarget mode marks a subset of pubkeys as invalid so that we can hit "invalid pubkey"
4537                 // branches, but we unwrap it below, so we arbitrarily select a dummy pubkey which is both
4538                 // valid, and valid in fuzztarget mode's arbitrary validity criteria:
4539                 let mut pk = [2; 33]; pk[1] = 0xff;
4540                 let dummy_pubkey = PublicKey::from_slice(&pk).unwrap();
4541                 let data_loss_protect = if self.cur_counterparty_commitment_transaction_number + 1 < INITIAL_COMMITMENT_NUMBER {
4542                         let remote_last_secret = self.commitment_secrets.get_secret(self.cur_counterparty_commitment_transaction_number + 2).unwrap();
4543                         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()));
4544                         OptionalField::Present(DataLossProtect {
4545                                 your_last_per_commitment_secret: remote_last_secret,
4546                                 my_current_per_commitment_point: dummy_pubkey
4547                         })
4548                 } else {
4549                         log_info!(logger, "Sending a data_loss_protect with no previous remote per_commitment_secret for channel {}", log_bytes!(self.channel_id()));
4550                         OptionalField::Present(DataLossProtect {
4551                                 your_last_per_commitment_secret: [0;32],
4552                                 my_current_per_commitment_point: dummy_pubkey,
4553                         })
4554                 };
4555                 msgs::ChannelReestablish {
4556                         channel_id: self.channel_id(),
4557                         // The protocol has two different commitment number concepts - the "commitment
4558                         // transaction number", which starts from 0 and counts up, and the "revocation key
4559                         // index" which starts at INITIAL_COMMITMENT_NUMBER and counts down. We track
4560                         // commitment transaction numbers by the index which will be used to reveal the
4561                         // revocation key for that commitment transaction, which means we have to convert them
4562                         // to protocol-level commitment numbers here...
4563
4564                         // next_local_commitment_number is the next commitment_signed number we expect to
4565                         // receive (indicating if they need to resend one that we missed).
4566                         next_local_commitment_number: INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number,
4567                         // We have to set next_remote_commitment_number to the next revoke_and_ack we expect to
4568                         // receive, however we track it by the next commitment number for a remote transaction
4569                         // (which is one further, as they always revoke previous commitment transaction, not
4570                         // the one we send) so we have to decrement by 1. Note that if
4571                         // cur_counterparty_commitment_transaction_number is INITIAL_COMMITMENT_NUMBER we will have
4572                         // dropped this channel on disconnect as it hasn't yet reached FundingSent so we can't
4573                         // overflow here.
4574                         next_remote_commitment_number: INITIAL_COMMITMENT_NUMBER - self.cur_counterparty_commitment_transaction_number - 1,
4575                         data_loss_protect,
4576                 }
4577         }
4578
4579
4580         // Send stuff to our remote peers:
4581
4582         /// Adds a pending outbound HTLC to this channel, note that you probably want
4583         /// send_htlc_and_commit instead cause you'll want both messages at once.
4584         ///
4585         /// This returns an optional UpdateAddHTLC as we may be in a state where we cannot add HTLCs on
4586         /// the wire:
4587         /// * In cases where we're waiting on the remote peer to send us a revoke_and_ack, we
4588         ///   wouldn't be able to determine what they actually ACK'ed if we have two sets of updates
4589         ///   awaiting ACK.
4590         /// * In cases where we're marked MonitorUpdateFailed, we cannot commit to a new state as we
4591         ///   may not yet have sent the previous commitment update messages and will need to regenerate
4592         ///   them.
4593         ///
4594         /// You MUST call send_commitment prior to calling any other methods on this Channel!
4595         ///
4596         /// If an Err is returned, it's a ChannelError::Ignore!
4597         pub fn send_htlc(&mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket) -> Result<Option<msgs::UpdateAddHTLC>, ChannelError> {
4598                 if (self.channel_state & (ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK)) != (ChannelState::ChannelFunded as u32) {
4599                         return Err(ChannelError::Ignore("Cannot send HTLC until channel is fully established and we haven't started shutting down".to_owned()));
4600                 }
4601                 let channel_total_msat = self.channel_value_satoshis * 1000;
4602                 if amount_msat > channel_total_msat {
4603                         return Err(ChannelError::Ignore(format!("Cannot send amount {}, because it is more than the total value of the channel {}", amount_msat, channel_total_msat)));
4604                 }
4605
4606                 if amount_msat == 0 {
4607                         return Err(ChannelError::Ignore("Cannot send 0-msat HTLC".to_owned()));
4608                 }
4609
4610                 if amount_msat < self.counterparty_htlc_minimum_msat {
4611                         return Err(ChannelError::Ignore(format!("Cannot send less than their minimum HTLC value ({})", self.counterparty_htlc_minimum_msat)));
4612                 }
4613
4614                 if (self.channel_state & (ChannelState::PeerDisconnected as u32)) != 0 {
4615                         // Note that this should never really happen, if we're !is_live() on receipt of an
4616                         // incoming HTLC for relay will result in us rejecting the HTLC and we won't allow
4617                         // the user to send directly into a !is_live() channel. However, if we
4618                         // disconnected during the time the previous hop was doing the commitment dance we may
4619                         // end up getting here after the forwarding delay. In any case, returning an
4620                         // IgnoreError will get ChannelManager to do the right thing and fail backwards now.
4621                         return Err(ChannelError::Ignore("Cannot send an HTLC while disconnected from channel counterparty".to_owned()));
4622                 }
4623
4624                 let inbound_stats = self.get_inbound_pending_htlc_stats();
4625                 let outbound_stats = self.get_outbound_pending_htlc_stats();
4626                 if outbound_stats.pending_htlcs + 1 > self.counterparty_max_accepted_htlcs as u32 {
4627                         return Err(ChannelError::Ignore(format!("Cannot push more than their max accepted HTLCs ({})", self.counterparty_max_accepted_htlcs)));
4628                 }
4629                 // Check their_max_htlc_value_in_flight_msat
4630                 if outbound_stats.pending_htlcs_value_msat + amount_msat > self.counterparty_max_htlc_value_in_flight_msat {
4631                         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)));
4632                 }
4633
4634                 if !self.is_outbound() {
4635                         // Check that we won't violate the remote channel reserve by adding this HTLC.
4636                         let counterparty_balance_msat = self.channel_value_satoshis * 1000 - self.value_to_self_msat;
4637                         let holder_selected_chan_reserve_msat = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis) * 1000;
4638                         let htlc_candidate = HTLCCandidate::new(amount_msat, HTLCInitiator::LocalOffered);
4639                         let counterparty_commit_tx_fee_msat = self.next_remote_commit_tx_fee_msat(htlc_candidate, None);
4640                         if counterparty_balance_msat < holder_selected_chan_reserve_msat + counterparty_commit_tx_fee_msat {
4641                                 return Err(ChannelError::Ignore("Cannot send value that would put counterparty balance under holder-announced channel reserve value".to_owned()));
4642                         }
4643                 }
4644
4645                 let exposure_dust_limit_success_sats = (self.get_dust_buffer_feerate() as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
4646                 if amount_msat / 1000 < exposure_dust_limit_success_sats {
4647                         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;
4648                         if on_counterparty_dust_htlc_exposure_msat > self.get_max_dust_htlc_exposure_msat() {
4649                                 return Err(ChannelError::Ignore(format!("Cannot send value that would put our exposure to dust HTLCs at {} over the limit {} on counterparty commitment tx",
4650                                         on_counterparty_dust_htlc_exposure_msat, self.get_max_dust_htlc_exposure_msat())));
4651                         }
4652                 }
4653
4654                 let exposure_dust_limit_timeout_sats = (self.get_dust_buffer_feerate() as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
4655                 if amount_msat / 1000 <  exposure_dust_limit_timeout_sats {
4656                         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;
4657                         if on_holder_dust_htlc_exposure_msat > self.get_max_dust_htlc_exposure_msat() {
4658                                 return Err(ChannelError::Ignore(format!("Cannot send value that would put our exposure to dust HTLCs at {} over the limit {} on holder commitment tx",
4659                                         on_holder_dust_htlc_exposure_msat, self.get_max_dust_htlc_exposure_msat())));
4660                         }
4661                 }
4662
4663                 let pending_value_to_self_msat = self.value_to_self_msat - outbound_stats.pending_htlcs_value_msat;
4664                 if pending_value_to_self_msat < amount_msat {
4665                         return Err(ChannelError::Ignore(format!("Cannot send value that would overdraw remaining funds. Amount: {}, pending value to self {}", amount_msat, pending_value_to_self_msat)));
4666                 }
4667
4668                 // `2 *` and extra HTLC are for the fee spike buffer.
4669                 let commit_tx_fee_msat = if self.is_outbound() {
4670                         let htlc_candidate = HTLCCandidate::new(amount_msat, HTLCInitiator::LocalOffered);
4671                         FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE * self.next_local_commit_tx_fee_msat(htlc_candidate, Some(()))
4672                 } else { 0 };
4673                 if pending_value_to_self_msat - amount_msat < commit_tx_fee_msat {
4674                         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 {}", pending_value_to_self_msat, commit_tx_fee_msat)));
4675                 }
4676
4677                 // Check self.counterparty_selected_channel_reserve_satoshis (the amount we must keep as
4678                 // reserve for the remote to have something to claim if we misbehave)
4679                 let chan_reserve_msat = self.counterparty_selected_channel_reserve_satoshis.unwrap() * 1000;
4680                 if pending_value_to_self_msat - amount_msat - commit_tx_fee_msat < chan_reserve_msat {
4681                         return Err(ChannelError::Ignore(format!("Cannot send value that would put our balance under counterparty-announced channel reserve value ({})", chan_reserve_msat)));
4682                 }
4683
4684                 // Now update local state:
4685                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
4686                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::AddHTLC {
4687                                 amount_msat,
4688                                 payment_hash,
4689                                 cltv_expiry,
4690                                 source,
4691                                 onion_routing_packet,
4692                         });
4693                         return Ok(None);
4694                 }
4695
4696                 self.pending_outbound_htlcs.push(OutboundHTLCOutput {
4697                         htlc_id: self.next_holder_htlc_id,
4698                         amount_msat,
4699                         payment_hash: payment_hash.clone(),
4700                         cltv_expiry,
4701                         state: OutboundHTLCState::LocalAnnounced(Box::new(onion_routing_packet.clone())),
4702                         source,
4703                 });
4704
4705                 let res = msgs::UpdateAddHTLC {
4706                         channel_id: self.channel_id,
4707                         htlc_id: self.next_holder_htlc_id,
4708                         amount_msat,
4709                         payment_hash,
4710                         cltv_expiry,
4711                         onion_routing_packet,
4712                 };
4713                 self.next_holder_htlc_id += 1;
4714
4715                 Ok(Some(res))
4716         }
4717
4718         /// Creates a signed commitment transaction to send to the remote peer.
4719         /// Always returns a ChannelError::Close if an immediately-preceding (read: the
4720         /// last call to this Channel) send_htlc returned Ok(Some(_)) and there is an Err.
4721         /// May panic if called except immediately after a successful, Ok(Some(_))-returning send_htlc.
4722         pub fn send_commitment<L: Deref>(&mut self, logger: &L) -> Result<(msgs::CommitmentSigned, ChannelMonitorUpdate), ChannelError> where L::Target: Logger {
4723                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
4724                         panic!("Cannot create commitment tx until channel is fully established");
4725                 }
4726                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
4727                         panic!("Cannot create commitment tx until remote revokes their previous commitment");
4728                 }
4729                 if (self.channel_state & (ChannelState::PeerDisconnected as u32)) == (ChannelState::PeerDisconnected as u32) {
4730                         panic!("Cannot create commitment tx while disconnected, as send_htlc will have returned an Err so a send_commitment precondition has been violated");
4731                 }
4732                 if (self.channel_state & (ChannelState::MonitorUpdateFailed as u32)) == (ChannelState::MonitorUpdateFailed as u32) {
4733                         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");
4734                 }
4735                 let mut have_updates = self.is_outbound() && self.pending_update_fee.is_some();
4736                 for htlc in self.pending_outbound_htlcs.iter() {
4737                         if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
4738                                 have_updates = true;
4739                         }
4740                         if have_updates { break; }
4741                 }
4742                 for htlc in self.pending_inbound_htlcs.iter() {
4743                         if let InboundHTLCState::LocalRemoved(_) = htlc.state {
4744                                 have_updates = true;
4745                         }
4746                         if have_updates { break; }
4747                 }
4748                 if !have_updates {
4749                         panic!("Cannot create commitment tx until we have some updates to send");
4750                 }
4751                 self.send_commitment_no_status_check(logger)
4752         }
4753         /// Only fails in case of bad keys
4754         fn send_commitment_no_status_check<L: Deref>(&mut self, logger: &L) -> Result<(msgs::CommitmentSigned, ChannelMonitorUpdate), ChannelError> where L::Target: Logger {
4755                 log_trace!(logger, "Updating HTLC state for a newly-sent commitment_signed...");
4756                 // We can upgrade the status of some HTLCs that are waiting on a commitment, even if we
4757                 // fail to generate this, we still are at least at a position where upgrading their status
4758                 // is acceptable.
4759                 for htlc in self.pending_inbound_htlcs.iter_mut() {
4760                         let new_state = if let &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(ref forward_info) = &htlc.state {
4761                                 Some(InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info.clone()))
4762                         } else { None };
4763                         if let Some(state) = new_state {
4764                                 log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce {} to AwaitingAnnouncedRemoteRevoke", log_bytes!(htlc.payment_hash.0));
4765                                 htlc.state = state;
4766                         }
4767                 }
4768                 for htlc in self.pending_outbound_htlcs.iter_mut() {
4769                         if let Some(fail_reason) = if let &mut OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref mut fail_reason) = &mut htlc.state {
4770                                 Some(fail_reason.take())
4771                         } else { None } {
4772                                 log_trace!(logger, " ...promoting outbound AwaitingRemoteRevokeToRemove {} to AwaitingRemovedRemoteRevoke", log_bytes!(htlc.payment_hash.0));
4773                                 htlc.state = OutboundHTLCState::AwaitingRemovedRemoteRevoke(fail_reason);
4774                         }
4775                 }
4776                 if let Some((feerate, update_state)) = self.pending_update_fee {
4777                         if update_state == FeeUpdateState::AwaitingRemoteRevokeToAnnounce {
4778                                 debug_assert!(!self.is_outbound());
4779                                 log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce fee update {} to Committed", feerate);
4780                                 self.feerate_per_kw = feerate;
4781                                 self.pending_update_fee = None;
4782                         }
4783                 }
4784                 self.resend_order = RAACommitmentOrder::RevokeAndACKFirst;
4785
4786                 let (res, counterparty_commitment_txid, htlcs) = match self.send_commitment_no_state_update(logger) {
4787                         Ok((res, (counterparty_commitment_tx, mut htlcs))) => {
4788                                 // Update state now that we've passed all the can-fail calls...
4789                                 let htlcs_no_ref: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)> =
4790                                         htlcs.drain(..).map(|(htlc, htlc_source)| (htlc, htlc_source.map(|source_ref| Box::new(source_ref.clone())))).collect();
4791                                 (res, counterparty_commitment_tx, htlcs_no_ref)
4792                         },
4793                         Err(e) => return Err(e),
4794                 };
4795
4796                 self.latest_monitor_update_id += 1;
4797                 let monitor_update = ChannelMonitorUpdate {
4798                         update_id: self.latest_monitor_update_id,
4799                         updates: vec![ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo {
4800                                 commitment_txid: counterparty_commitment_txid,
4801                                 htlc_outputs: htlcs.clone(),
4802                                 commitment_number: self.cur_counterparty_commitment_transaction_number,
4803                                 their_revocation_point: self.counterparty_cur_commitment_point.unwrap()
4804                         }]
4805                 };
4806                 self.channel_state |= ChannelState::AwaitingRemoteRevoke as u32;
4807                 Ok((res, monitor_update))
4808         }
4809
4810         /// Only fails in case of bad keys. Used for channel_reestablish commitment_signed generation
4811         /// when we shouldn't change HTLC/channel state.
4812         fn send_commitment_no_state_update<L: Deref>(&self, logger: &L) -> Result<(msgs::CommitmentSigned, (Txid, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>)), ChannelError> where L::Target: Logger {
4813                 let counterparty_keys = self.build_remote_transaction_keys()?;
4814                 let counterparty_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, true, logger);
4815                 let feerate_per_kw = counterparty_commitment_tx.1;
4816                 let counterparty_commitment_txid = counterparty_commitment_tx.0.trust().txid();
4817                 let (signature, htlc_signatures);
4818
4819                 #[cfg(any(test, feature = "fuzztarget"))]
4820                 {
4821                         if !self.is_outbound() {
4822                                 let projected_commit_tx_info = self.next_remote_commitment_tx_fee_info_cached.lock().unwrap().take();
4823                                 *self.next_local_commitment_tx_fee_info_cached.lock().unwrap() = None;
4824                                 if let Some(info) = projected_commit_tx_info {
4825                                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len();
4826                                         if info.total_pending_htlcs == total_pending_htlcs
4827                                                 && info.next_holder_htlc_id == self.next_holder_htlc_id
4828                                                 && info.next_counterparty_htlc_id == self.next_counterparty_htlc_id
4829                                                 && info.feerate == self.feerate_per_kw {
4830                                                         let actual_fee = self.commit_tx_fee_msat(counterparty_commitment_tx.2);
4831                                                         assert_eq!(actual_fee, info.fee);
4832                                                 }
4833                                 }
4834                         }
4835                 }
4836
4837                 {
4838                         let mut htlcs = Vec::with_capacity(counterparty_commitment_tx.3.len());
4839                         for &(ref htlc, _) in counterparty_commitment_tx.3.iter() {
4840                                 htlcs.push(htlc);
4841                         }
4842
4843                         let res = self.holder_signer.sign_counterparty_commitment(&counterparty_commitment_tx.0, &self.secp_ctx)
4844                                 .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?;
4845                         signature = res.0;
4846                         htlc_signatures = res.1;
4847
4848                         log_trace!(logger, "Signed remote commitment tx {} (txid {}) with redeemscript {} -> {} in channel {}",
4849                                 encode::serialize_hex(&counterparty_commitment_tx.0.trust().built_transaction().transaction),
4850                                 &counterparty_commitment_txid, encode::serialize_hex(&self.get_funding_redeemscript()),
4851                                 log_bytes!(signature.serialize_compact()[..]), log_bytes!(self.channel_id()));
4852
4853                         for (ref htlc_sig, ref htlc) in htlc_signatures.iter().zip(htlcs) {
4854                                 log_trace!(logger, "Signed remote HTLC tx {} with redeemscript {} with pubkey {} -> {} in channel {}",
4855                                         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)),
4856                                         encode::serialize_hex(&chan_utils::get_htlc_redeemscript(&htlc, &counterparty_keys)),
4857                                         log_bytes!(counterparty_keys.broadcaster_htlc_key.serialize()),
4858                                         log_bytes!(htlc_sig.serialize_compact()[..]), log_bytes!(self.channel_id()));
4859                         }
4860                 }
4861
4862                 Ok((msgs::CommitmentSigned {
4863                         channel_id: self.channel_id,
4864                         signature,
4865                         htlc_signatures,
4866                 }, (counterparty_commitment_txid, counterparty_commitment_tx.3)))
4867         }
4868
4869         /// Adds a pending outbound HTLC to this channel, and creates a signed commitment transaction
4870         /// to send to the remote peer in one go.
4871         /// Shorthand for calling send_htlc() followed by send_commitment(), see docs on those for
4872         /// more info.
4873         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 {
4874                 match self.send_htlc(amount_msat, payment_hash, cltv_expiry, source, onion_routing_packet)? {
4875                         Some(update_add_htlc) => {
4876                                 let (commitment_signed, monitor_update) = self.send_commitment_no_status_check(logger)?;
4877                                 Ok(Some((update_add_htlc, commitment_signed, monitor_update)))
4878                         },
4879                         None => Ok(None)
4880                 }
4881         }
4882
4883         /// Get forwarding information for the counterparty.
4884         pub fn counterparty_forwarding_info(&self) -> Option<CounterpartyForwardingInfo> {
4885                 self.counterparty_forwarding_info.clone()
4886         }
4887
4888         pub fn channel_update(&mut self, msg: &msgs::ChannelUpdate) -> Result<(), ChannelError> {
4889                 if msg.contents.htlc_minimum_msat >= self.channel_value_satoshis * 1000 {
4890                         return Err(ChannelError::Close("Minimum htlc value is greater than channel value".to_string()));
4891                 }
4892                 self.counterparty_forwarding_info = Some(CounterpartyForwardingInfo {
4893                         fee_base_msat: msg.contents.fee_base_msat,
4894                         fee_proportional_millionths: msg.contents.fee_proportional_millionths,
4895                         cltv_expiry_delta: msg.contents.cltv_expiry_delta
4896                 });
4897
4898                 Ok(())
4899         }
4900
4901         /// Begins the shutdown process, getting a message for the remote peer and returning all
4902         /// holding cell HTLCs for payment failure.
4903         pub fn get_shutdown<K: Deref>(&mut self, keys_provider: &K, their_features: &InitFeatures, target_feerate_sats_per_kw: Option<u32>)
4904         -> Result<(msgs::Shutdown, Option<ChannelMonitorUpdate>, Vec<(HTLCSource, PaymentHash)>), APIError>
4905         where K::Target: KeysInterface<Signer = Signer> {
4906                 for htlc in self.pending_outbound_htlcs.iter() {
4907                         if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
4908                                 return Err(APIError::APIMisuseError{err: "Cannot begin shutdown with pending HTLCs. Process pending events first".to_owned()});
4909                         }
4910                 }
4911                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != 0 {
4912                         if (self.channel_state & ChannelState::LocalShutdownSent as u32) == ChannelState::LocalShutdownSent as u32 {
4913                                 return Err(APIError::APIMisuseError{err: "Shutdown already in progress".to_owned()});
4914                         }
4915                         else if (self.channel_state & ChannelState::RemoteShutdownSent as u32) == ChannelState::RemoteShutdownSent as u32 {
4916                                 return Err(APIError::ChannelUnavailable{err: "Shutdown already in progress by remote".to_owned()});
4917                         }
4918                 }
4919                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
4920                 if self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32) != 0 {
4921                         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()});
4922                 }
4923
4924                 let update_shutdown_script = match self.shutdown_scriptpubkey {
4925                         Some(_) => false,
4926                         None => {
4927                                 let shutdown_scriptpubkey = keys_provider.get_shutdown_scriptpubkey();
4928                                 if !shutdown_scriptpubkey.is_compatible(their_features) {
4929                                         return Err(APIError::IncompatibleShutdownScript { script: shutdown_scriptpubkey.clone() });
4930                                 }
4931                                 self.shutdown_scriptpubkey = Some(shutdown_scriptpubkey);
4932                                 true
4933                         },
4934                 };
4935
4936                 // From here on out, we may not fail!
4937                 self.target_closing_feerate_sats_per_kw = target_feerate_sats_per_kw;
4938                 if self.channel_state < ChannelState::FundingSent as u32 {
4939                         self.channel_state = ChannelState::ShutdownComplete as u32;
4940                 } else {
4941                         self.channel_state |= ChannelState::LocalShutdownSent as u32;
4942                 }
4943                 self.update_time_counter += 1;
4944
4945                 let monitor_update = if update_shutdown_script {
4946                         self.latest_monitor_update_id += 1;
4947                         Some(ChannelMonitorUpdate {
4948                                 update_id: self.latest_monitor_update_id,
4949                                 updates: vec![ChannelMonitorUpdateStep::ShutdownScript {
4950                                         scriptpubkey: self.get_closing_scriptpubkey(),
4951                                 }],
4952                         })
4953                 } else { None };
4954                 let shutdown = msgs::Shutdown {
4955                         channel_id: self.channel_id,
4956                         scriptpubkey: self.get_closing_scriptpubkey(),
4957                 };
4958
4959                 // Go ahead and drop holding cell updates as we'd rather fail payments than wait to send
4960                 // our shutdown until we've committed all of the pending changes.
4961                 self.holding_cell_update_fee = None;
4962                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
4963                 self.holding_cell_htlc_updates.retain(|htlc_update| {
4964                         match htlc_update {
4965                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
4966                                         dropped_outbound_htlcs.push((source.clone(), payment_hash.clone()));
4967                                         false
4968                                 },
4969                                 _ => true
4970                         }
4971                 });
4972
4973                 Ok((shutdown, monitor_update, dropped_outbound_htlcs))
4974         }
4975
4976         /// Gets the latest commitment transaction and any dependent transactions for relay (forcing
4977         /// shutdown of this channel - no more calls into this Channel may be made afterwards except
4978         /// those explicitly stated to be allowed after shutdown completes, eg some simple getters).
4979         /// Also returns the list of payment_hashes for channels which we can safely fail backwards
4980         /// immediately (others we will have to allow to time out).
4981         pub fn force_shutdown(&mut self, should_broadcast: bool) -> (Option<(OutPoint, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>) {
4982                 // Note that we MUST only generate a monitor update that indicates force-closure - we're
4983                 // called during initialization prior to the chain_monitor in the encompassing ChannelManager
4984                 // being fully configured in some cases. Thus, its likely any monitor events we generate will
4985                 // be delayed in being processed! See the docs for `ChannelManagerReadArgs` for more.
4986                 assert!(self.channel_state != ChannelState::ShutdownComplete as u32);
4987
4988                 // We go ahead and "free" any holding cell HTLCs or HTLCs we haven't yet committed to and
4989                 // return them to fail the payment.
4990                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
4991                 for htlc_update in self.holding_cell_htlc_updates.drain(..) {
4992                         match htlc_update {
4993                                 HTLCUpdateAwaitingACK::AddHTLC { source, payment_hash, .. } => {
4994                                         dropped_outbound_htlcs.push((source, payment_hash));
4995                                 },
4996                                 _ => {}
4997                         }
4998                 }
4999                 let monitor_update = if let Some(funding_txo) = self.get_funding_txo() {
5000                         // If we haven't yet exchanged funding signatures (ie channel_state < FundingSent),
5001                         // returning a channel monitor update here would imply a channel monitor update before
5002                         // we even registered the channel monitor to begin with, which is invalid.
5003                         // Thus, if we aren't actually at a point where we could conceivably broadcast the
5004                         // funding transaction, don't return a funding txo (which prevents providing the
5005                         // monitor update to the user, even if we return one).
5006                         // See test_duplicate_chan_id and test_pre_lockin_no_chan_closed_update for more.
5007                         if self.channel_state & (ChannelState::FundingSent as u32 | ChannelState::ChannelFunded as u32 | ChannelState::ShutdownComplete as u32) != 0 {
5008                                 self.latest_monitor_update_id += 1;
5009                                 Some((funding_txo, ChannelMonitorUpdate {
5010                                         update_id: self.latest_monitor_update_id,
5011                                         updates: vec![ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast }],
5012                                 }))
5013                         } else { None }
5014                 } else { None };
5015
5016                 self.channel_state = ChannelState::ShutdownComplete as u32;
5017                 self.update_time_counter += 1;
5018                 (monitor_update, dropped_outbound_htlcs)
5019         }
5020 }
5021
5022 const SERIALIZATION_VERSION: u8 = 2;
5023 const MIN_SERIALIZATION_VERSION: u8 = 1;
5024
5025 impl_writeable_tlv_based_enum!(InboundHTLCRemovalReason,;
5026         (0, FailRelay),
5027         (1, FailMalformed),
5028         (2, Fulfill),
5029 );
5030
5031 impl Writeable for ChannelUpdateStatus {
5032         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
5033                 // We only care about writing out the current state as it was announced, ie only either
5034                 // Enabled or Disabled. In the case of DisabledStaged, we most recently announced the
5035                 // channel as enabled, so we write 0. For EnabledStaged, we similarly write a 1.
5036                 match self {
5037                         ChannelUpdateStatus::Enabled => 0u8.write(writer)?,
5038                         ChannelUpdateStatus::DisabledStaged => 0u8.write(writer)?,
5039                         ChannelUpdateStatus::EnabledStaged => 1u8.write(writer)?,
5040                         ChannelUpdateStatus::Disabled => 1u8.write(writer)?,
5041                 }
5042                 Ok(())
5043         }
5044 }
5045
5046 impl Readable for ChannelUpdateStatus {
5047         fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
5048                 Ok(match <u8 as Readable>::read(reader)? {
5049                         0 => ChannelUpdateStatus::Enabled,
5050                         1 => ChannelUpdateStatus::Disabled,
5051                         _ => return Err(DecodeError::InvalidValue),
5052                 })
5053         }
5054 }
5055
5056 impl<Signer: Sign> Writeable for Channel<Signer> {
5057         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
5058                 // Note that we write out as if remove_uncommitted_htlcs_and_mark_paused had just been
5059                 // called.
5060
5061                 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
5062
5063                 self.user_id.write(writer)?;
5064
5065                 // Write out the old serialization for the config object. This is read by version-1
5066                 // deserializers, but we will read the version in the TLV at the end instead.
5067                 self.config.forwarding_fee_proportional_millionths.write(writer)?;
5068                 self.config.cltv_expiry_delta.write(writer)?;
5069                 self.config.announced_channel.write(writer)?;
5070                 self.config.commit_upfront_shutdown_pubkey.write(writer)?;
5071
5072                 self.channel_id.write(writer)?;
5073                 (self.channel_state | ChannelState::PeerDisconnected as u32).write(writer)?;
5074                 self.channel_value_satoshis.write(writer)?;
5075
5076                 self.latest_monitor_update_id.write(writer)?;
5077
5078                 let mut key_data = VecWriter(Vec::new());
5079                 self.holder_signer.write(&mut key_data)?;
5080                 assert!(key_data.0.len() < core::usize::MAX);
5081                 assert!(key_data.0.len() < core::u32::MAX as usize);
5082                 (key_data.0.len() as u32).write(writer)?;
5083                 writer.write_all(&key_data.0[..])?;
5084
5085                 // Write out the old serialization for shutdown_pubkey for backwards compatibility, if
5086                 // deserialized from that format.
5087                 match self.shutdown_scriptpubkey.as_ref().and_then(|script| script.as_legacy_pubkey()) {
5088                         Some(shutdown_pubkey) => shutdown_pubkey.write(writer)?,
5089                         None => [0u8; PUBLIC_KEY_SIZE].write(writer)?,
5090                 }
5091                 self.destination_script.write(writer)?;
5092
5093                 self.cur_holder_commitment_transaction_number.write(writer)?;
5094                 self.cur_counterparty_commitment_transaction_number.write(writer)?;
5095                 self.value_to_self_msat.write(writer)?;
5096
5097                 let mut dropped_inbound_htlcs = 0;
5098                 for htlc in self.pending_inbound_htlcs.iter() {
5099                         if let InboundHTLCState::RemoteAnnounced(_) = htlc.state {
5100                                 dropped_inbound_htlcs += 1;
5101                         }
5102                 }
5103                 (self.pending_inbound_htlcs.len() as u64 - dropped_inbound_htlcs).write(writer)?;
5104                 for htlc in self.pending_inbound_htlcs.iter() {
5105                         if let &InboundHTLCState::RemoteAnnounced(_) = &htlc.state {
5106                                 continue; // Drop
5107                         }
5108                         htlc.htlc_id.write(writer)?;
5109                         htlc.amount_msat.write(writer)?;
5110                         htlc.cltv_expiry.write(writer)?;
5111                         htlc.payment_hash.write(writer)?;
5112                         match &htlc.state {
5113                                 &InboundHTLCState::RemoteAnnounced(_) => unreachable!(),
5114                                 &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(ref htlc_state) => {
5115                                         1u8.write(writer)?;
5116                                         htlc_state.write(writer)?;
5117                                 },
5118                                 &InboundHTLCState::AwaitingAnnouncedRemoteRevoke(ref htlc_state) => {
5119                                         2u8.write(writer)?;
5120                                         htlc_state.write(writer)?;
5121                                 },
5122                                 &InboundHTLCState::Committed => {
5123                                         3u8.write(writer)?;
5124                                 },
5125                                 &InboundHTLCState::LocalRemoved(ref removal_reason) => {
5126                                         4u8.write(writer)?;
5127                                         removal_reason.write(writer)?;
5128                                 },
5129                         }
5130                 }
5131
5132                 (self.pending_outbound_htlcs.len() as u64).write(writer)?;
5133                 for htlc in self.pending_outbound_htlcs.iter() {
5134                         htlc.htlc_id.write(writer)?;
5135                         htlc.amount_msat.write(writer)?;
5136                         htlc.cltv_expiry.write(writer)?;
5137                         htlc.payment_hash.write(writer)?;
5138                         htlc.source.write(writer)?;
5139                         match &htlc.state {
5140                                 &OutboundHTLCState::LocalAnnounced(ref onion_packet) => {
5141                                         0u8.write(writer)?;
5142                                         onion_packet.write(writer)?;
5143                                 },
5144                                 &OutboundHTLCState::Committed => {
5145                                         1u8.write(writer)?;
5146                                 },
5147                                 &OutboundHTLCState::RemoteRemoved(_) => {
5148                                         // Treat this as a Committed because we haven't received the CS - they'll
5149                                         // resend the claim/fail on reconnect as we all (hopefully) the missing CS.
5150                                         1u8.write(writer)?;
5151                                 },
5152                                 &OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref fail_reason) => {
5153                                         3u8.write(writer)?;
5154                                         fail_reason.write(writer)?;
5155                                 },
5156                                 &OutboundHTLCState::AwaitingRemovedRemoteRevoke(ref fail_reason) => {
5157                                         4u8.write(writer)?;
5158                                         fail_reason.write(writer)?;
5159                                 },
5160                         }
5161                 }
5162
5163                 (self.holding_cell_htlc_updates.len() as u64).write(writer)?;
5164                 for update in self.holding_cell_htlc_updates.iter() {
5165                         match update {
5166                                 &HTLCUpdateAwaitingACK::AddHTLC { ref amount_msat, ref cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet } => {
5167                                         0u8.write(writer)?;
5168                                         amount_msat.write(writer)?;
5169                                         cltv_expiry.write(writer)?;
5170                                         payment_hash.write(writer)?;
5171                                         source.write(writer)?;
5172                                         onion_routing_packet.write(writer)?;
5173                                 },
5174                                 &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, ref htlc_id } => {
5175                                         1u8.write(writer)?;
5176                                         payment_preimage.write(writer)?;
5177                                         htlc_id.write(writer)?;
5178                                 },
5179                                 &HTLCUpdateAwaitingACK::FailHTLC { ref htlc_id, ref err_packet } => {
5180                                         2u8.write(writer)?;
5181                                         htlc_id.write(writer)?;
5182                                         err_packet.write(writer)?;
5183                                 }
5184                         }
5185                 }
5186
5187                 match self.resend_order {
5188                         RAACommitmentOrder::CommitmentFirst => 0u8.write(writer)?,
5189                         RAACommitmentOrder::RevokeAndACKFirst => 1u8.write(writer)?,
5190                 }
5191
5192                 self.monitor_pending_funding_locked.write(writer)?;
5193                 self.monitor_pending_revoke_and_ack.write(writer)?;
5194                 self.monitor_pending_commitment_signed.write(writer)?;
5195
5196                 (self.monitor_pending_forwards.len() as u64).write(writer)?;
5197                 for &(ref pending_forward, ref htlc_id) in self.monitor_pending_forwards.iter() {
5198                         pending_forward.write(writer)?;
5199                         htlc_id.write(writer)?;
5200                 }
5201
5202                 (self.monitor_pending_failures.len() as u64).write(writer)?;
5203                 for &(ref htlc_source, ref payment_hash, ref fail_reason) in self.monitor_pending_failures.iter() {
5204                         htlc_source.write(writer)?;
5205                         payment_hash.write(writer)?;
5206                         fail_reason.write(writer)?;
5207                 }
5208
5209                 if self.is_outbound() {
5210                         self.pending_update_fee.map(|(a, _)| a).write(writer)?;
5211                 } else if let Some((feerate, FeeUpdateState::AwaitingRemoteRevokeToAnnounce)) = self.pending_update_fee {
5212                         Some(feerate).write(writer)?;
5213                 } else {
5214                         // As for inbound HTLCs, if the update was only announced and never committed in a
5215                         // commitment_signed, drop it.
5216                         None::<u32>.write(writer)?;
5217                 }
5218                 self.holding_cell_update_fee.write(writer)?;
5219
5220                 self.next_holder_htlc_id.write(writer)?;
5221                 (self.next_counterparty_htlc_id - dropped_inbound_htlcs).write(writer)?;
5222                 self.update_time_counter.write(writer)?;
5223                 self.feerate_per_kw.write(writer)?;
5224
5225                 // Versions prior to 0.0.100 expected to read the fields of `last_sent_closing_fee` here,
5226                 // however we are supposed to restart shutdown fee negotiation on reconnect (and wipe
5227                 // `last_send_closing_fee` in `remove_uncommitted_htlcs_and_mark_paused`) so we should never
5228                 // consider the stale state on reload.
5229                 0u8.write(writer)?;
5230
5231                 self.funding_tx_confirmed_in.write(writer)?;
5232                 self.funding_tx_confirmation_height.write(writer)?;
5233                 self.short_channel_id.write(writer)?;
5234
5235                 self.counterparty_dust_limit_satoshis.write(writer)?;
5236                 self.holder_dust_limit_satoshis.write(writer)?;
5237                 self.counterparty_max_htlc_value_in_flight_msat.write(writer)?;
5238
5239                 // Note that this field is ignored by 0.0.99+ as the TLV Optional variant is used instead.
5240                 self.counterparty_selected_channel_reserve_satoshis.unwrap_or(0).write(writer)?;
5241
5242                 self.counterparty_htlc_minimum_msat.write(writer)?;
5243                 self.holder_htlc_minimum_msat.write(writer)?;
5244                 self.counterparty_max_accepted_htlcs.write(writer)?;
5245
5246                 // Note that this field is ignored by 0.0.99+ as the TLV Optional variant is used instead.
5247                 self.minimum_depth.unwrap_or(0).write(writer)?;
5248
5249                 match &self.counterparty_forwarding_info {
5250                         Some(info) => {
5251                                 1u8.write(writer)?;
5252                                 info.fee_base_msat.write(writer)?;
5253                                 info.fee_proportional_millionths.write(writer)?;
5254                                 info.cltv_expiry_delta.write(writer)?;
5255                         },
5256                         None => 0u8.write(writer)?
5257                 }
5258
5259                 self.channel_transaction_parameters.write(writer)?;
5260                 self.funding_transaction.write(writer)?;
5261
5262                 self.counterparty_cur_commitment_point.write(writer)?;
5263                 self.counterparty_prev_commitment_point.write(writer)?;
5264                 self.counterparty_node_id.write(writer)?;
5265
5266                 self.counterparty_shutdown_scriptpubkey.write(writer)?;
5267
5268                 self.commitment_secrets.write(writer)?;
5269
5270                 self.channel_update_status.write(writer)?;
5271
5272                 #[cfg(any(test, feature = "fuzztarget"))]
5273                 (self.historical_inbound_htlc_fulfills.len() as u64).write(writer)?;
5274                 #[cfg(any(test, feature = "fuzztarget"))]
5275                 for htlc in self.historical_inbound_htlc_fulfills.iter() {
5276                         htlc.write(writer)?;
5277                 }
5278
5279                 // If the channel type is something other than only-static-remote-key, then we need to have
5280                 // older clients fail to deserialize this channel at all. If the type is
5281                 // only-static-remote-key, we simply consider it "default" and don't write the channel type
5282                 // out at all.
5283                 let chan_type = if self.channel_type != ChannelTypeFeatures::only_static_remote_key() {
5284                         Some(&self.channel_type) } else { None };
5285
5286                 write_tlv_fields!(writer, {
5287                         (0, self.announcement_sigs, option),
5288                         // minimum_depth and counterparty_selected_channel_reserve_satoshis used to have a
5289                         // default value instead of being Option<>al. Thus, to maintain compatibility we write
5290                         // them twice, once with their original default values above, and once as an option
5291                         // here. On the read side, old versions will simply ignore the odd-type entries here,
5292                         // and new versions map the default values to None and allow the TLV entries here to
5293                         // override that.
5294                         (1, self.minimum_depth, option),
5295                         (2, chan_type, option),
5296                         (3, self.counterparty_selected_channel_reserve_satoshis, option),
5297                         (5, self.config, required),
5298                         (7, self.shutdown_scriptpubkey, option),
5299                         (9, self.target_closing_feerate_sats_per_kw, option),
5300                         (11, self.monitor_pending_finalized_fulfills, vec_type),
5301                         (13, self.channel_creation_height, required),
5302                 });
5303
5304                 Ok(())
5305         }
5306 }
5307
5308 const MAX_ALLOC_SIZE: usize = 64*1024;
5309 impl<'a, Signer: Sign, K: Deref> ReadableArgs<(&'a K, u32)> for Channel<Signer>
5310                 where K::Target: KeysInterface<Signer = Signer> {
5311         fn read<R : io::Read>(reader: &mut R, args: (&'a K, u32)) -> Result<Self, DecodeError> {
5312                 let (keys_source, serialized_height) = args;
5313                 let ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
5314
5315                 let user_id = Readable::read(reader)?;
5316
5317                 let mut config = Some(ChannelConfig::default());
5318                 if ver == 1 {
5319                         // Read the old serialization of the ChannelConfig from version 0.0.98.
5320                         config.as_mut().unwrap().forwarding_fee_proportional_millionths = Readable::read(reader)?;
5321                         config.as_mut().unwrap().cltv_expiry_delta = Readable::read(reader)?;
5322                         config.as_mut().unwrap().announced_channel = Readable::read(reader)?;
5323                         config.as_mut().unwrap().commit_upfront_shutdown_pubkey = Readable::read(reader)?;
5324                 } else {
5325                         // Read the 8 bytes of backwards-compatibility ChannelConfig data.
5326                         let mut _val: u64 = Readable::read(reader)?;
5327                 }
5328
5329                 let channel_id = Readable::read(reader)?;
5330                 let channel_state = Readable::read(reader)?;
5331                 let channel_value_satoshis = Readable::read(reader)?;
5332
5333                 let latest_monitor_update_id = Readable::read(reader)?;
5334
5335                 let keys_len: u32 = Readable::read(reader)?;
5336                 let mut keys_data = Vec::with_capacity(cmp::min(keys_len as usize, MAX_ALLOC_SIZE));
5337                 while keys_data.len() != keys_len as usize {
5338                         // Read 1KB at a time to avoid accidentally allocating 4GB on corrupted channel keys
5339                         let mut data = [0; 1024];
5340                         let read_slice = &mut data[0..cmp::min(1024, keys_len as usize - keys_data.len())];
5341                         reader.read_exact(read_slice)?;
5342                         keys_data.extend_from_slice(read_slice);
5343                 }
5344                 let holder_signer = keys_source.read_chan_signer(&keys_data)?;
5345
5346                 // Read the old serialization for shutdown_pubkey, preferring the TLV field later if set.
5347                 let mut shutdown_scriptpubkey = match <PublicKey as Readable>::read(reader) {
5348                         Ok(pubkey) => Some(ShutdownScript::new_p2wpkh_from_pubkey(pubkey)),
5349                         Err(_) => None,
5350                 };
5351                 let destination_script = Readable::read(reader)?;
5352
5353                 let cur_holder_commitment_transaction_number = Readable::read(reader)?;
5354                 let cur_counterparty_commitment_transaction_number = Readable::read(reader)?;
5355                 let value_to_self_msat = Readable::read(reader)?;
5356
5357                 let pending_inbound_htlc_count: u64 = Readable::read(reader)?;
5358                 let mut pending_inbound_htlcs = Vec::with_capacity(cmp::min(pending_inbound_htlc_count as usize, OUR_MAX_HTLCS as usize));
5359                 for _ in 0..pending_inbound_htlc_count {
5360                         pending_inbound_htlcs.push(InboundHTLCOutput {
5361                                 htlc_id: Readable::read(reader)?,
5362                                 amount_msat: Readable::read(reader)?,
5363                                 cltv_expiry: Readable::read(reader)?,
5364                                 payment_hash: Readable::read(reader)?,
5365                                 state: match <u8 as Readable>::read(reader)? {
5366                                         1 => InboundHTLCState::AwaitingRemoteRevokeToAnnounce(Readable::read(reader)?),
5367                                         2 => InboundHTLCState::AwaitingAnnouncedRemoteRevoke(Readable::read(reader)?),
5368                                         3 => InboundHTLCState::Committed,
5369                                         4 => InboundHTLCState::LocalRemoved(Readable::read(reader)?),
5370                                         _ => return Err(DecodeError::InvalidValue),
5371                                 },
5372                         });
5373                 }
5374
5375                 let pending_outbound_htlc_count: u64 = Readable::read(reader)?;
5376                 let mut pending_outbound_htlcs = Vec::with_capacity(cmp::min(pending_outbound_htlc_count as usize, OUR_MAX_HTLCS as usize));
5377                 for _ in 0..pending_outbound_htlc_count {
5378                         pending_outbound_htlcs.push(OutboundHTLCOutput {
5379                                 htlc_id: Readable::read(reader)?,
5380                                 amount_msat: Readable::read(reader)?,
5381                                 cltv_expiry: Readable::read(reader)?,
5382                                 payment_hash: Readable::read(reader)?,
5383                                 source: Readable::read(reader)?,
5384                                 state: match <u8 as Readable>::read(reader)? {
5385                                         0 => OutboundHTLCState::LocalAnnounced(Box::new(Readable::read(reader)?)),
5386                                         1 => OutboundHTLCState::Committed,
5387                                         2 => OutboundHTLCState::RemoteRemoved(Readable::read(reader)?),
5388                                         3 => OutboundHTLCState::AwaitingRemoteRevokeToRemove(Readable::read(reader)?),
5389                                         4 => OutboundHTLCState::AwaitingRemovedRemoteRevoke(Readable::read(reader)?),
5390                                         _ => return Err(DecodeError::InvalidValue),
5391                                 },
5392                         });
5393                 }
5394
5395                 let holding_cell_htlc_update_count: u64 = Readable::read(reader)?;
5396                 let mut holding_cell_htlc_updates = Vec::with_capacity(cmp::min(holding_cell_htlc_update_count as usize, OUR_MAX_HTLCS as usize*2));
5397                 for _ in 0..holding_cell_htlc_update_count {
5398                         holding_cell_htlc_updates.push(match <u8 as Readable>::read(reader)? {
5399                                 0 => HTLCUpdateAwaitingACK::AddHTLC {
5400                                         amount_msat: Readable::read(reader)?,
5401                                         cltv_expiry: Readable::read(reader)?,
5402                                         payment_hash: Readable::read(reader)?,
5403                                         source: Readable::read(reader)?,
5404                                         onion_routing_packet: Readable::read(reader)?,
5405                                 },
5406                                 1 => HTLCUpdateAwaitingACK::ClaimHTLC {
5407                                         payment_preimage: Readable::read(reader)?,
5408                                         htlc_id: Readable::read(reader)?,
5409                                 },
5410                                 2 => HTLCUpdateAwaitingACK::FailHTLC {
5411                                         htlc_id: Readable::read(reader)?,
5412                                         err_packet: Readable::read(reader)?,
5413                                 },
5414                                 _ => return Err(DecodeError::InvalidValue),
5415                         });
5416                 }
5417
5418                 let resend_order = match <u8 as Readable>::read(reader)? {
5419                         0 => RAACommitmentOrder::CommitmentFirst,
5420                         1 => RAACommitmentOrder::RevokeAndACKFirst,
5421                         _ => return Err(DecodeError::InvalidValue),
5422                 };
5423
5424                 let monitor_pending_funding_locked = Readable::read(reader)?;
5425                 let monitor_pending_revoke_and_ack = Readable::read(reader)?;
5426                 let monitor_pending_commitment_signed = Readable::read(reader)?;
5427
5428                 let monitor_pending_forwards_count: u64 = Readable::read(reader)?;
5429                 let mut monitor_pending_forwards = Vec::with_capacity(cmp::min(monitor_pending_forwards_count as usize, OUR_MAX_HTLCS as usize));
5430                 for _ in 0..monitor_pending_forwards_count {
5431                         monitor_pending_forwards.push((Readable::read(reader)?, Readable::read(reader)?));
5432                 }
5433
5434                 let monitor_pending_failures_count: u64 = Readable::read(reader)?;
5435                 let mut monitor_pending_failures = Vec::with_capacity(cmp::min(monitor_pending_failures_count as usize, OUR_MAX_HTLCS as usize));
5436                 for _ in 0..monitor_pending_failures_count {
5437                         monitor_pending_failures.push((Readable::read(reader)?, Readable::read(reader)?, Readable::read(reader)?));
5438                 }
5439
5440                 let pending_update_fee_value: Option<u32> = Readable::read(reader)?;
5441
5442                 let holding_cell_update_fee = Readable::read(reader)?;
5443
5444                 let next_holder_htlc_id = Readable::read(reader)?;
5445                 let next_counterparty_htlc_id = Readable::read(reader)?;
5446                 let update_time_counter = Readable::read(reader)?;
5447                 let feerate_per_kw = Readable::read(reader)?;
5448
5449                 // Versions prior to 0.0.100 expected to read the fields of `last_sent_closing_fee` here,
5450                 // however we are supposed to restart shutdown fee negotiation on reconnect (and wipe
5451                 // `last_send_closing_fee` in `remove_uncommitted_htlcs_and_mark_paused`) so we should never
5452                 // consider the stale state on reload.
5453                 match <u8 as Readable>::read(reader)? {
5454                         0 => {},
5455                         1 => {
5456                                 let _: u32 = Readable::read(reader)?;
5457                                 let _: u64 = Readable::read(reader)?;
5458                                 let _: Signature = Readable::read(reader)?;
5459                         },
5460                         _ => return Err(DecodeError::InvalidValue),
5461                 }
5462
5463                 let funding_tx_confirmed_in = Readable::read(reader)?;
5464                 let funding_tx_confirmation_height = Readable::read(reader)?;
5465                 let short_channel_id = Readable::read(reader)?;
5466
5467                 let counterparty_dust_limit_satoshis = Readable::read(reader)?;
5468                 let holder_dust_limit_satoshis = Readable::read(reader)?;
5469                 let counterparty_max_htlc_value_in_flight_msat = Readable::read(reader)?;
5470                 let mut counterparty_selected_channel_reserve_satoshis = None;
5471                 if ver == 1 {
5472                         // Read the old serialization from version 0.0.98.
5473                         counterparty_selected_channel_reserve_satoshis = Some(Readable::read(reader)?);
5474                 } else {
5475                         // Read the 8 bytes of backwards-compatibility data.
5476                         let _dummy: u64 = Readable::read(reader)?;
5477                 }
5478                 let counterparty_htlc_minimum_msat = Readable::read(reader)?;
5479                 let holder_htlc_minimum_msat = Readable::read(reader)?;
5480                 let counterparty_max_accepted_htlcs = Readable::read(reader)?;
5481
5482                 let mut minimum_depth = None;
5483                 if ver == 1 {
5484                         // Read the old serialization from version 0.0.98.
5485                         minimum_depth = Some(Readable::read(reader)?);
5486                 } else {
5487                         // Read the 4 bytes of backwards-compatibility data.
5488                         let _dummy: u32 = Readable::read(reader)?;
5489                 }
5490
5491                 let counterparty_forwarding_info = match <u8 as Readable>::read(reader)? {
5492                         0 => None,
5493                         1 => Some(CounterpartyForwardingInfo {
5494                                 fee_base_msat: Readable::read(reader)?,
5495                                 fee_proportional_millionths: Readable::read(reader)?,
5496                                 cltv_expiry_delta: Readable::read(reader)?,
5497                         }),
5498                         _ => return Err(DecodeError::InvalidValue),
5499                 };
5500
5501                 let channel_parameters: ChannelTransactionParameters = Readable::read(reader)?;
5502                 let funding_transaction = Readable::read(reader)?;
5503
5504                 let counterparty_cur_commitment_point = Readable::read(reader)?;
5505
5506                 let counterparty_prev_commitment_point = Readable::read(reader)?;
5507                 let counterparty_node_id = Readable::read(reader)?;
5508
5509                 let counterparty_shutdown_scriptpubkey = Readable::read(reader)?;
5510                 let commitment_secrets = Readable::read(reader)?;
5511
5512                 let channel_update_status = Readable::read(reader)?;
5513
5514                 #[cfg(any(test, feature = "fuzztarget"))]
5515                 let mut historical_inbound_htlc_fulfills = HashSet::new();
5516                 #[cfg(any(test, feature = "fuzztarget"))]
5517                 {
5518                         let htlc_fulfills_len: u64 = Readable::read(reader)?;
5519                         for _ in 0..htlc_fulfills_len {
5520                                 assert!(historical_inbound_htlc_fulfills.insert(Readable::read(reader)?));
5521                         }
5522                 }
5523
5524                 let pending_update_fee = if let Some(feerate) = pending_update_fee_value {
5525                         Some((feerate, if channel_parameters.is_outbound_from_holder {
5526                                 FeeUpdateState::Outbound
5527                         } else {
5528                                 FeeUpdateState::AwaitingRemoteRevokeToAnnounce
5529                         }))
5530                 } else {
5531                         None
5532                 };
5533
5534                 let mut announcement_sigs = None;
5535                 let mut target_closing_feerate_sats_per_kw = None;
5536                 let mut monitor_pending_finalized_fulfills = Some(Vec::new());
5537                 // Prior to supporting channel type negotiation, all of our channels were static_remotekey
5538                 // only, so we default to that if none was written.
5539                 let mut channel_type = Some(ChannelTypeFeatures::only_static_remote_key());
5540                 let mut channel_creation_height = Some(serialized_height);
5541                 read_tlv_fields!(reader, {
5542                         (0, announcement_sigs, option),
5543                         (1, minimum_depth, option),
5544                         (2, channel_type, option),
5545                         (3, counterparty_selected_channel_reserve_satoshis, option),
5546                         (5, config, option), // Note that if none is provided we will *not* overwrite the existing one.
5547                         (7, shutdown_scriptpubkey, option),
5548                         (9, target_closing_feerate_sats_per_kw, option),
5549                         (11, monitor_pending_finalized_fulfills, vec_type),
5550                         (13, channel_creation_height, option),
5551                 });
5552
5553                 let chan_features = channel_type.as_ref().unwrap();
5554                 if chan_features.supports_unknown_bits() || chan_features.requires_unknown_bits() {
5555                         // If the channel was written by a new version and negotiated with features we don't
5556                         // understand yet, refuse to read it.
5557                         return Err(DecodeError::UnknownRequiredFeature);
5558                 }
5559
5560                 let mut secp_ctx = Secp256k1::new();
5561                 secp_ctx.seeded_randomize(&keys_source.get_secure_random_bytes());
5562
5563                 Ok(Channel {
5564                         user_id,
5565
5566                         config: config.unwrap(),
5567                         channel_id,
5568                         channel_state,
5569                         secp_ctx,
5570                         channel_value_satoshis,
5571
5572                         latest_monitor_update_id,
5573
5574                         holder_signer,
5575                         shutdown_scriptpubkey,
5576                         destination_script,
5577
5578                         cur_holder_commitment_transaction_number,
5579                         cur_counterparty_commitment_transaction_number,
5580                         value_to_self_msat,
5581
5582                         pending_inbound_htlcs,
5583                         pending_outbound_htlcs,
5584                         holding_cell_htlc_updates,
5585
5586                         resend_order,
5587
5588                         monitor_pending_funding_locked,
5589                         monitor_pending_revoke_and_ack,
5590                         monitor_pending_commitment_signed,
5591                         monitor_pending_forwards,
5592                         monitor_pending_failures,
5593                         monitor_pending_finalized_fulfills: monitor_pending_finalized_fulfills.unwrap(),
5594
5595                         pending_update_fee,
5596                         holding_cell_update_fee,
5597                         next_holder_htlc_id,
5598                         next_counterparty_htlc_id,
5599                         update_time_counter,
5600                         feerate_per_kw,
5601
5602                         #[cfg(debug_assertions)]
5603                         holder_max_commitment_tx_output: Mutex::new((0, 0)),
5604                         #[cfg(debug_assertions)]
5605                         counterparty_max_commitment_tx_output: Mutex::new((0, 0)),
5606
5607                         last_sent_closing_fee: None,
5608                         pending_counterparty_closing_signed: None,
5609                         closing_fee_limits: None,
5610                         target_closing_feerate_sats_per_kw,
5611
5612                         funding_tx_confirmed_in,
5613                         funding_tx_confirmation_height,
5614                         short_channel_id,
5615                         channel_creation_height: channel_creation_height.unwrap(),
5616
5617                         counterparty_dust_limit_satoshis,
5618                         holder_dust_limit_satoshis,
5619                         counterparty_max_htlc_value_in_flight_msat,
5620                         counterparty_selected_channel_reserve_satoshis,
5621                         counterparty_htlc_minimum_msat,
5622                         holder_htlc_minimum_msat,
5623                         counterparty_max_accepted_htlcs,
5624                         minimum_depth,
5625
5626                         counterparty_forwarding_info,
5627
5628                         channel_transaction_parameters: channel_parameters,
5629                         funding_transaction,
5630
5631                         counterparty_cur_commitment_point,
5632                         counterparty_prev_commitment_point,
5633                         counterparty_node_id,
5634
5635                         counterparty_shutdown_scriptpubkey,
5636
5637                         commitment_secrets,
5638
5639                         channel_update_status,
5640                         closing_signed_in_flight: false,
5641
5642                         announcement_sigs,
5643
5644                         #[cfg(any(test, feature = "fuzztarget"))]
5645                         next_local_commitment_tx_fee_info_cached: Mutex::new(None),
5646                         #[cfg(any(test, feature = "fuzztarget"))]
5647                         next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
5648
5649                         workaround_lnd_bug_4006: None,
5650
5651                         #[cfg(any(test, feature = "fuzztarget"))]
5652                         historical_inbound_htlc_fulfills,
5653
5654                         channel_type: channel_type.unwrap(),
5655                 })
5656         }
5657 }
5658
5659 #[cfg(test)]
5660 mod tests {
5661         use bitcoin::util::bip143;
5662         use bitcoin::consensus::encode::serialize;
5663         use bitcoin::blockdata::script::{Script, Builder};
5664         use bitcoin::blockdata::transaction::{Transaction, TxOut, SigHashType};
5665         use bitcoin::blockdata::constants::genesis_block;
5666         use bitcoin::blockdata::opcodes;
5667         use bitcoin::network::constants::Network;
5668         use bitcoin::hashes::hex::FromHex;
5669         use hex;
5670         use ln::{PaymentPreimage, PaymentHash};
5671         use ln::channelmanager::{HTLCSource, PaymentId};
5672         use ln::channel::{Channel,InboundHTLCOutput,OutboundHTLCOutput,InboundHTLCState,OutboundHTLCState,HTLCOutputInCommitment,HTLCCandidate,HTLCInitiator,TxCreationKeys};
5673         use ln::channel::MAX_FUNDING_SATOSHIS;
5674         use ln::features::InitFeatures;
5675         use ln::msgs::{ChannelUpdate, DataLossProtect, DecodeError, OptionalField, UnsignedChannelUpdate};
5676         use ln::script::ShutdownScript;
5677         use ln::chan_utils;
5678         use ln::chan_utils::{ChannelPublicKeys, HolderCommitmentTransaction, CounterpartyChannelTransactionParameters, HTLC_SUCCESS_TX_WEIGHT, HTLC_TIMEOUT_TX_WEIGHT};
5679         use chain::BestBlock;
5680         use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
5681         use chain::keysinterface::{InMemorySigner, KeysInterface, BaseSign};
5682         use chain::transaction::OutPoint;
5683         use util::config::UserConfig;
5684         use util::enforcing_trait_impls::EnforcingSigner;
5685         use util::errors::APIError;
5686         use util::test_utils;
5687         use util::test_utils::OnGetShutdownScriptpubkey;
5688         use util::logger::Logger;
5689         use bitcoin::secp256k1::{Secp256k1, Message, Signature, All};
5690         use bitcoin::secp256k1::ffi::Signature as FFISignature;
5691         use bitcoin::secp256k1::key::{SecretKey,PublicKey};
5692         use bitcoin::secp256k1::recovery::RecoverableSignature;
5693         use bitcoin::hashes::sha256::Hash as Sha256;
5694         use bitcoin::hashes::Hash;
5695         use bitcoin::hash_types::{Txid, WPubkeyHash};
5696         use core::num::NonZeroU8;
5697         use sync::Arc;
5698         use prelude::*;
5699
5700         struct TestFeeEstimator {
5701                 fee_est: u32
5702         }
5703         impl FeeEstimator for TestFeeEstimator {
5704                 fn get_est_sat_per_1000_weight(&self, _: ConfirmationTarget) -> u32 {
5705                         self.fee_est
5706                 }
5707         }
5708
5709         #[test]
5710         fn test_max_funding_satoshis() {
5711                 assert!(MAX_FUNDING_SATOSHIS <= 21_000_000 * 100_000_000,
5712                         "MAX_FUNDING_SATOSHIS is greater than all satoshis in existence");
5713         }
5714
5715         struct Keys {
5716                 signer: InMemorySigner,
5717         }
5718         impl KeysInterface for Keys {
5719                 type Signer = InMemorySigner;
5720
5721                 fn get_node_secret(&self) -> SecretKey { panic!(); }
5722                 fn get_destination_script(&self) -> Script {
5723                         let secp_ctx = Secp256k1::signing_only();
5724                         let channel_monitor_claim_key = SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap();
5725                         let channel_monitor_claim_key_hash = WPubkeyHash::hash(&PublicKey::from_secret_key(&secp_ctx, &channel_monitor_claim_key).serialize());
5726                         Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&channel_monitor_claim_key_hash[..]).into_script()
5727                 }
5728
5729                 fn get_shutdown_scriptpubkey(&self) -> ShutdownScript {
5730                         let secp_ctx = Secp256k1::signing_only();
5731                         let channel_close_key = SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap();
5732                         ShutdownScript::new_p2wpkh_from_pubkey(PublicKey::from_secret_key(&secp_ctx, &channel_close_key))
5733                 }
5734
5735                 fn get_channel_signer(&self, _inbound: bool, _channel_value_satoshis: u64) -> InMemorySigner {
5736                         self.signer.clone()
5737                 }
5738                 fn get_secure_random_bytes(&self) -> [u8; 32] { [0; 32] }
5739                 fn read_chan_signer(&self, _data: &[u8]) -> Result<Self::Signer, DecodeError> { panic!(); }
5740                 fn sign_invoice(&self, _invoice_preimage: Vec<u8>) -> Result<RecoverableSignature, ()> { panic!(); }
5741         }
5742
5743         fn public_from_secret_hex(secp_ctx: &Secp256k1<All>, hex: &str) -> PublicKey {
5744                 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode(hex).unwrap()[..]).unwrap())
5745         }
5746
5747         #[test]
5748         fn upfront_shutdown_script_incompatibility() {
5749                 let features = InitFeatures::known().clear_shutdown_anysegwit();
5750                 let non_v0_segwit_shutdown_script =
5751                         ShutdownScript::new_witness_program(NonZeroU8::new(16).unwrap(), &[0, 40]).unwrap();
5752
5753                 let seed = [42; 32];
5754                 let network = Network::Testnet;
5755                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5756                 keys_provider.expect(OnGetShutdownScriptpubkey {
5757                         returns: non_v0_segwit_shutdown_script.clone(),
5758                 });
5759
5760                 let fee_estimator = TestFeeEstimator { fee_est: 253 };
5761                 let secp_ctx = Secp256k1::new();
5762                 let node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5763                 let config = UserConfig::default();
5764                 match Channel::<EnforcingSigner>::new_outbound(&&fee_estimator, &&keys_provider, node_id, &features, 10000000, 100000, 42, &config, 0) {
5765                         Err(APIError::IncompatibleShutdownScript { script }) => {
5766                                 assert_eq!(script.into_inner(), non_v0_segwit_shutdown_script.into_inner());
5767                         },
5768                         Err(e) => panic!("Unexpected error: {:?}", e),
5769                         Ok(_) => panic!("Expected error"),
5770                 }
5771         }
5772
5773         // Check that, during channel creation, we use the same feerate in the open channel message
5774         // as we do in the Channel object creation itself.
5775         #[test]
5776         fn test_open_channel_msg_fee() {
5777                 let original_fee = 253;
5778                 let mut fee_est = TestFeeEstimator{fee_est: original_fee };
5779                 let secp_ctx = Secp256k1::new();
5780                 let seed = [42; 32];
5781                 let network = Network::Testnet;
5782                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5783
5784                 let node_a_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5785                 let config = UserConfig::default();
5786                 let node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&fee_est, &&keys_provider, node_a_node_id, &InitFeatures::known(), 10000000, 100000, 42, &config, 0).unwrap();
5787
5788                 // Now change the fee so we can check that the fee in the open_channel message is the
5789                 // same as the old fee.
5790                 fee_est.fee_est = 500;
5791                 let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.block_hash());
5792                 assert_eq!(open_channel_msg.feerate_per_kw, original_fee);
5793         }
5794
5795         #[test]
5796         fn test_holder_vs_counterparty_dust_limit() {
5797                 // Test that when calculating the local and remote commitment transaction fees, the correct
5798                 // dust limits are used.
5799                 let feeest = TestFeeEstimator{fee_est: 15000};
5800                 let secp_ctx = Secp256k1::new();
5801                 let seed = [42; 32];
5802                 let network = Network::Testnet;
5803                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5804
5805                 // Go through the flow of opening a channel between two nodes, making sure
5806                 // they have different dust limits.
5807
5808                 // Create Node A's channel pointing to Node B's pubkey
5809                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5810                 let config = UserConfig::default();
5811                 let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, &InitFeatures::known(), 10000000, 100000, 42, &config, 0).unwrap();
5812
5813                 // Create Node B's channel by receiving Node A's open_channel message
5814                 // Make sure A's dust limit is as we expect.
5815                 let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.block_hash());
5816                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
5817                 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();
5818
5819                 // Node B --> Node A: accept channel, explicitly setting B's dust limit.
5820                 let mut accept_channel_msg = node_b_chan.get_accept_channel();
5821                 accept_channel_msg.dust_limit_satoshis = 546;
5822                 node_a_chan.accept_channel(&accept_channel_msg, &config, &InitFeatures::known()).unwrap();
5823                 node_a_chan.holder_dust_limit_satoshis = 1560;
5824
5825                 // Put some inbound and outbound HTLCs in A's channel.
5826                 let htlc_amount_msat = 11_092_000; // put an amount below A's effective dust limit but above B's.
5827                 node_a_chan.pending_inbound_htlcs.push(InboundHTLCOutput {
5828                         htlc_id: 0,
5829                         amount_msat: htlc_amount_msat,
5830                         payment_hash: PaymentHash(Sha256::hash(&[42; 32]).into_inner()),
5831                         cltv_expiry: 300000000,
5832                         state: InboundHTLCState::Committed,
5833                 });
5834
5835                 node_a_chan.pending_outbound_htlcs.push(OutboundHTLCOutput {
5836                         htlc_id: 1,
5837                         amount_msat: htlc_amount_msat, // put an amount below A's dust amount but above B's.
5838                         payment_hash: PaymentHash(Sha256::hash(&[43; 32]).into_inner()),
5839                         cltv_expiry: 200000000,
5840                         state: OutboundHTLCState::Committed,
5841                         source: HTLCSource::OutboundRoute {
5842                                 path: Vec::new(),
5843                                 session_priv: SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(),
5844                                 first_hop_htlc_msat: 548,
5845                                 payment_id: PaymentId([42; 32]),
5846                                 payment_secret: None,
5847                                 payee: None,
5848                         }
5849                 });
5850
5851                 // Make sure when Node A calculates their local commitment transaction, none of the HTLCs pass
5852                 // the dust limit check.
5853                 let htlc_candidate = HTLCCandidate::new(htlc_amount_msat, HTLCInitiator::LocalOffered);
5854                 let local_commit_tx_fee = node_a_chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
5855                 let local_commit_fee_0_htlcs = node_a_chan.commit_tx_fee_msat(0);
5856                 assert_eq!(local_commit_tx_fee, local_commit_fee_0_htlcs);
5857
5858                 // Finally, make sure that when Node A calculates the remote's commitment transaction fees, all
5859                 // of the HTLCs are seen to be above the dust limit.
5860                 node_a_chan.channel_transaction_parameters.is_outbound_from_holder = false;
5861                 let remote_commit_fee_3_htlcs = node_a_chan.commit_tx_fee_msat(3);
5862                 let htlc_candidate = HTLCCandidate::new(htlc_amount_msat, HTLCInitiator::LocalOffered);
5863                 let remote_commit_tx_fee = node_a_chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
5864                 assert_eq!(remote_commit_tx_fee, remote_commit_fee_3_htlcs);
5865         }
5866
5867         #[test]
5868         fn test_timeout_vs_success_htlc_dust_limit() {
5869                 // Make sure that when `next_remote_commit_tx_fee_msat` and `next_local_commit_tx_fee_msat`
5870                 // calculate the real dust limits for HTLCs (i.e. the dust limit given by the counterparty
5871                 // *plus* the fees paid for the HTLC) they don't swap `HTLC_SUCCESS_TX_WEIGHT` for
5872                 // `HTLC_TIMEOUT_TX_WEIGHT`, and vice versa.
5873                 let fee_est = TestFeeEstimator{fee_est: 253 };
5874                 let secp_ctx = Secp256k1::new();
5875                 let seed = [42; 32];
5876                 let network = Network::Testnet;
5877                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5878
5879                 let node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5880                 let config = UserConfig::default();
5881                 let mut chan = Channel::<EnforcingSigner>::new_outbound(&&fee_est, &&keys_provider, node_id, &InitFeatures::known(), 10000000, 100000, 42, &config, 0).unwrap();
5882
5883                 let commitment_tx_fee_0_htlcs = chan.commit_tx_fee_msat(0);
5884                 let commitment_tx_fee_1_htlc = chan.commit_tx_fee_msat(1);
5885
5886                 // If HTLC_SUCCESS_TX_WEIGHT and HTLC_TIMEOUT_TX_WEIGHT were swapped: then this HTLC would be
5887                 // counted as dust when it shouldn't be.
5888                 let htlc_amt_above_timeout = ((253 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + chan.holder_dust_limit_satoshis + 1) * 1000;
5889                 let htlc_candidate = HTLCCandidate::new(htlc_amt_above_timeout, HTLCInitiator::LocalOffered);
5890                 let commitment_tx_fee = chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
5891                 assert_eq!(commitment_tx_fee, commitment_tx_fee_1_htlc);
5892
5893                 // If swapped: this HTLC would be counted as non-dust when it shouldn't be.
5894                 let dust_htlc_amt_below_success = ((253 * HTLC_SUCCESS_TX_WEIGHT / 1000) + chan.holder_dust_limit_satoshis - 1) * 1000;
5895                 let htlc_candidate = HTLCCandidate::new(dust_htlc_amt_below_success, HTLCInitiator::RemoteOffered);
5896                 let commitment_tx_fee = chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
5897                 assert_eq!(commitment_tx_fee, commitment_tx_fee_0_htlcs);
5898
5899                 chan.channel_transaction_parameters.is_outbound_from_holder = false;
5900
5901                 // If swapped: this HTLC would be counted as non-dust when it shouldn't be.
5902                 let dust_htlc_amt_above_timeout = ((253 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + chan.counterparty_dust_limit_satoshis + 1) * 1000;
5903                 let htlc_candidate = HTLCCandidate::new(dust_htlc_amt_above_timeout, HTLCInitiator::LocalOffered);
5904                 let commitment_tx_fee = chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
5905                 assert_eq!(commitment_tx_fee, commitment_tx_fee_0_htlcs);
5906
5907                 // If swapped: this HTLC would be counted as dust when it shouldn't be.
5908                 let htlc_amt_below_success = ((253 * HTLC_SUCCESS_TX_WEIGHT / 1000) + chan.counterparty_dust_limit_satoshis - 1) * 1000;
5909                 let htlc_candidate = HTLCCandidate::new(htlc_amt_below_success, HTLCInitiator::RemoteOffered);
5910                 let commitment_tx_fee = chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
5911                 assert_eq!(commitment_tx_fee, commitment_tx_fee_1_htlc);
5912         }
5913
5914         #[test]
5915         fn channel_reestablish_no_updates() {
5916                 let feeest = TestFeeEstimator{fee_est: 15000};
5917                 let logger = test_utils::TestLogger::new();
5918                 let secp_ctx = Secp256k1::new();
5919                 let seed = [42; 32];
5920                 let network = Network::Testnet;
5921                 let best_block = BestBlock::from_genesis(network);
5922                 let chain_hash = best_block.block_hash();
5923                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5924
5925                 // Go through the flow of opening a channel between two nodes.
5926
5927                 // Create Node A's channel pointing to Node B's pubkey
5928                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5929                 let config = UserConfig::default();
5930                 let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, &InitFeatures::known(), 10000000, 100000, 42, &config, 0).unwrap();
5931
5932                 // Create Node B's channel by receiving Node A's open_channel message
5933                 let open_channel_msg = node_a_chan.get_open_channel(chain_hash);
5934                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
5935                 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();
5936
5937                 // Node B --> Node A: accept channel
5938                 let accept_channel_msg = node_b_chan.get_accept_channel();
5939                 node_a_chan.accept_channel(&accept_channel_msg, &config, &InitFeatures::known()).unwrap();
5940
5941                 // Node A --> Node B: funding created
5942                 let output_script = node_a_chan.get_funding_redeemscript();
5943                 let tx = Transaction { version: 1, lock_time: 0, input: Vec::new(), output: vec![TxOut {
5944                         value: 10000000, script_pubkey: output_script.clone(),
5945                 }]};
5946                 let funding_outpoint = OutPoint{ txid: tx.txid(), index: 0 };
5947                 let funding_created_msg = node_a_chan.get_outbound_funding_created(tx.clone(), funding_outpoint, &&logger).unwrap();
5948                 let (funding_signed_msg, _) = node_b_chan.funding_created(&funding_created_msg, best_block, &&logger).unwrap();
5949
5950                 // Node B --> Node A: funding signed
5951                 let _ = node_a_chan.funding_signed(&funding_signed_msg, best_block, &&logger);
5952
5953                 // Now disconnect the two nodes and check that the commitment point in
5954                 // Node B's channel_reestablish message is sane.
5955                 node_b_chan.remove_uncommitted_htlcs_and_mark_paused(&&logger);
5956                 let msg = node_b_chan.get_channel_reestablish(&&logger);
5957                 assert_eq!(msg.next_local_commitment_number, 1); // now called next_commitment_number
5958                 assert_eq!(msg.next_remote_commitment_number, 0); // now called next_revocation_number
5959                 match msg.data_loss_protect {
5960                         OptionalField::Present(DataLossProtect { your_last_per_commitment_secret, .. }) => {
5961                                 assert_eq!(your_last_per_commitment_secret, [0; 32]);
5962                         },
5963                         _ => panic!()
5964                 }
5965
5966                 // Check that the commitment point in Node A's channel_reestablish message
5967                 // is sane.
5968                 node_a_chan.remove_uncommitted_htlcs_and_mark_paused(&&logger);
5969                 let msg = node_a_chan.get_channel_reestablish(&&logger);
5970                 assert_eq!(msg.next_local_commitment_number, 1); // now called next_commitment_number
5971                 assert_eq!(msg.next_remote_commitment_number, 0); // now called next_revocation_number
5972                 match msg.data_loss_protect {
5973                         OptionalField::Present(DataLossProtect { your_last_per_commitment_secret, .. }) => {
5974                                 assert_eq!(your_last_per_commitment_secret, [0; 32]);
5975                         },
5976                         _ => panic!()
5977                 }
5978         }
5979
5980         #[test]
5981         fn channel_update() {
5982                 let feeest = TestFeeEstimator{fee_est: 15000};
5983                 let secp_ctx = Secp256k1::new();
5984                 let seed = [42; 32];
5985                 let network = Network::Testnet;
5986                 let chain_hash = genesis_block(network).header.block_hash();
5987                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5988
5989                 // Create a channel.
5990                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5991                 let config = UserConfig::default();
5992                 let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, &InitFeatures::known(), 10000000, 100000, 42, &config, 0).unwrap();
5993                 assert!(node_a_chan.counterparty_forwarding_info.is_none());
5994                 assert_eq!(node_a_chan.holder_htlc_minimum_msat, 1); // the default
5995                 assert!(node_a_chan.counterparty_forwarding_info().is_none());
5996
5997                 // Make sure that receiving a channel update will update the Channel as expected.
5998                 let update = ChannelUpdate {
5999                         contents: UnsignedChannelUpdate {
6000                                 chain_hash,
6001                                 short_channel_id: 0,
6002                                 timestamp: 0,
6003                                 flags: 0,
6004                                 cltv_expiry_delta: 100,
6005                                 htlc_minimum_msat: 5,
6006                                 htlc_maximum_msat: OptionalField::Absent,
6007                                 fee_base_msat: 110,
6008                                 fee_proportional_millionths: 11,
6009                                 excess_data: Vec::new(),
6010                         },
6011                         signature: Signature::from(unsafe { FFISignature::new() })
6012                 };
6013                 node_a_chan.channel_update(&update).unwrap();
6014
6015                 // The counterparty can send an update with a higher minimum HTLC, but that shouldn't
6016                 // change our official htlc_minimum_msat.
6017                 assert_eq!(node_a_chan.holder_htlc_minimum_msat, 1);
6018                 match node_a_chan.counterparty_forwarding_info() {
6019                         Some(info) => {
6020                                 assert_eq!(info.cltv_expiry_delta, 100);
6021                                 assert_eq!(info.fee_base_msat, 110);
6022                                 assert_eq!(info.fee_proportional_millionths, 11);
6023                         },
6024                         None => panic!("expected counterparty forwarding info to be Some")
6025                 }
6026         }
6027
6028         #[test]
6029         fn outbound_commitment_test() {
6030                 // Test vectors from BOLT 3 Appendix C:
6031                 let feeest = TestFeeEstimator{fee_est: 15000};
6032                 let logger : Arc<Logger> = Arc::new(test_utils::TestLogger::new());
6033                 let secp_ctx = Secp256k1::new();
6034
6035                 let mut signer = InMemorySigner::new(
6036                         &secp_ctx,
6037                         SecretKey::from_slice(&hex::decode("30ff4956bbdd3222d44cc5e8a1261dab1e07957bdac5ae88fe3261ef321f3749").unwrap()[..]).unwrap(),
6038                         SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(),
6039                         SecretKey::from_slice(&hex::decode("1111111111111111111111111111111111111111111111111111111111111111").unwrap()[..]).unwrap(),
6040                         SecretKey::from_slice(&hex::decode("3333333333333333333333333333333333333333333333333333333333333333").unwrap()[..]).unwrap(),
6041                         SecretKey::from_slice(&hex::decode("1111111111111111111111111111111111111111111111111111111111111111").unwrap()[..]).unwrap(),
6042
6043                         // These aren't set in the test vectors:
6044                         [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],
6045                         10_000_000,
6046                         [0; 32]
6047                 );
6048
6049                 assert_eq!(signer.pubkeys().funding_pubkey.serialize()[..],
6050                                 hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]);
6051                 let keys_provider = Keys { signer: signer.clone() };
6052
6053                 let counterparty_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
6054                 let mut config = UserConfig::default();
6055                 config.channel_options.announced_channel = false;
6056                 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
6057                 chan.holder_dust_limit_satoshis = 546;
6058                 chan.counterparty_selected_channel_reserve_satoshis = Some(0); // Filled in in accept_channel
6059
6060                 let funding_info = OutPoint{ txid: Txid::from_hex("8984484a580b825b9972d7adb15050b3ab624ccd731946b3eeddb92f4e7ef6be").unwrap(), index: 0 };
6061
6062                 let counterparty_pubkeys = ChannelPublicKeys {
6063                         funding_pubkey: public_from_secret_hex(&secp_ctx, "1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13"),
6064                         revocation_basepoint: PublicKey::from_slice(&hex::decode("02466d7fcae563e5cb09a0d1870bb580344804617879a14949cf22285f1bae3f27").unwrap()[..]).unwrap(),
6065                         payment_point: public_from_secret_hex(&secp_ctx, "4444444444444444444444444444444444444444444444444444444444444444"),
6066                         delayed_payment_basepoint: public_from_secret_hex(&secp_ctx, "1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13"),
6067                         htlc_basepoint: public_from_secret_hex(&secp_ctx, "4444444444444444444444444444444444444444444444444444444444444444")
6068                 };
6069                 chan.channel_transaction_parameters.counterparty_parameters = Some(
6070                         CounterpartyChannelTransactionParameters {
6071                                 pubkeys: counterparty_pubkeys.clone(),
6072                                 selected_contest_delay: 144
6073                         });
6074                 chan.channel_transaction_parameters.funding_outpoint = Some(funding_info);
6075                 signer.ready_channel(&chan.channel_transaction_parameters);
6076
6077                 assert_eq!(counterparty_pubkeys.payment_point.serialize()[..],
6078                            hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
6079
6080                 assert_eq!(counterparty_pubkeys.funding_pubkey.serialize()[..],
6081                            hex::decode("030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c1").unwrap()[..]);
6082
6083                 assert_eq!(counterparty_pubkeys.htlc_basepoint.serialize()[..],
6084                            hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
6085
6086                 // We can't just use build_holder_transaction_keys here as the per_commitment_secret is not
6087                 // derived from a commitment_seed, so instead we copy it here and call
6088                 // build_commitment_transaction.
6089                 let delayed_payment_base = &chan.holder_signer.pubkeys().delayed_payment_basepoint;
6090                 let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
6091                 let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
6092                 let htlc_basepoint = &chan.holder_signer.pubkeys().htlc_basepoint;
6093                 let keys = TxCreationKeys::derive_new(&secp_ctx, &per_commitment_point, delayed_payment_base, htlc_basepoint, &counterparty_pubkeys.revocation_basepoint, &counterparty_pubkeys.htlc_basepoint).unwrap();
6094
6095                 macro_rules! test_commitment {
6096                         ( $counterparty_sig_hex: expr, $sig_hex: expr, $tx_hex: expr, {
6097                                 $( { $htlc_idx: expr, $counterparty_htlc_sig_hex: expr, $htlc_sig_hex: expr, $htlc_tx_hex: expr } ), *
6098                         } ) => { {
6099                                 let (commitment_tx, htlcs): (_, Vec<HTLCOutputInCommitment>) = {
6100                                         let mut res = chan.build_commitment_transaction(0xffffffffffff - 42, &keys, true, false, &logger);
6101
6102                                         let htlcs = res.3.drain(..)
6103                                                 .filter_map(|(htlc, _)| if htlc.transaction_output_index.is_some() { Some(htlc) } else { None })
6104                                                 .collect();
6105                                         (res.0, htlcs)
6106                                 };
6107                                 let trusted_tx = commitment_tx.trust();
6108                                 let unsigned_tx = trusted_tx.built_transaction();
6109                                 let redeemscript = chan.get_funding_redeemscript();
6110                                 let counterparty_signature = Signature::from_der(&hex::decode($counterparty_sig_hex).unwrap()[..]).unwrap();
6111                                 let sighash = unsigned_tx.get_sighash_all(&redeemscript, chan.channel_value_satoshis);
6112                                 secp_ctx.verify(&sighash, &counterparty_signature, chan.counterparty_funding_pubkey()).unwrap();
6113
6114                                 let mut per_htlc: Vec<(HTLCOutputInCommitment, Option<Signature>)> = Vec::new();
6115                                 per_htlc.clear(); // Don't warn about excess mut for no-HTLC calls
6116                                 let mut counterparty_htlc_sigs = Vec::new();
6117                                 counterparty_htlc_sigs.clear(); // Don't warn about excess mut for no-HTLC calls
6118                                 $({
6119                                         let remote_signature = Signature::from_der(&hex::decode($counterparty_htlc_sig_hex).unwrap()[..]).unwrap();
6120                                         per_htlc.push((htlcs[$htlc_idx].clone(), Some(remote_signature)));
6121                                         counterparty_htlc_sigs.push(remote_signature);
6122                                 })*
6123                                 assert_eq!(htlcs.len(), per_htlc.len());
6124
6125                                 let holder_commitment_tx = HolderCommitmentTransaction::new(
6126                                         commitment_tx.clone(),
6127                                         counterparty_signature,
6128                                         counterparty_htlc_sigs,
6129                                         &chan.holder_signer.pubkeys().funding_pubkey,
6130                                         chan.counterparty_funding_pubkey()
6131                                 );
6132                                 let (holder_sig, htlc_sigs) = signer.sign_holder_commitment_and_htlcs(&holder_commitment_tx, &secp_ctx).unwrap();
6133                                 assert_eq!(Signature::from_der(&hex::decode($sig_hex).unwrap()[..]).unwrap(), holder_sig, "holder_sig");
6134
6135                                 let funding_redeemscript = chan.get_funding_redeemscript();
6136                                 let tx = holder_commitment_tx.add_holder_sig(&funding_redeemscript, holder_sig);
6137                                 assert_eq!(serialize(&tx)[..], hex::decode($tx_hex).unwrap()[..], "tx");
6138
6139                                 // ((htlc, counterparty_sig), (index, holder_sig))
6140                                 let mut htlc_sig_iter = holder_commitment_tx.htlcs().iter().zip(&holder_commitment_tx.counterparty_htlc_sigs).zip(htlc_sigs.iter().enumerate());
6141
6142                                 $({
6143                                         let remote_signature = Signature::from_der(&hex::decode($counterparty_htlc_sig_hex).unwrap()[..]).unwrap();
6144
6145                                         let ref htlc = htlcs[$htlc_idx];
6146                                         let htlc_tx = chan_utils::build_htlc_transaction(&unsigned_tx.txid, chan.feerate_per_kw,
6147                                                 chan.get_counterparty_selected_contest_delay().unwrap(),
6148                                                 &htlc, &keys.broadcaster_delayed_payment_key, &keys.revocation_key);
6149                                         let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys);
6150                                         let htlc_sighash = Message::from_slice(&bip143::SigHashCache::new(&htlc_tx).signature_hash(0, &htlc_redeemscript, htlc.amount_msat / 1000, SigHashType::All)[..]).unwrap();
6151                                         secp_ctx.verify(&htlc_sighash, &remote_signature, &keys.countersignatory_htlc_key).unwrap();
6152
6153                                         let mut preimage: Option<PaymentPreimage> = None;
6154                                         if !htlc.offered {
6155                                                 for i in 0..5 {
6156                                                         let out = PaymentHash(Sha256::hash(&[i; 32]).into_inner());
6157                                                         if out == htlc.payment_hash {
6158                                                                 preimage = Some(PaymentPreimage([i; 32]));
6159                                                         }
6160                                                 }
6161
6162                                                 assert!(preimage.is_some());
6163                                         }
6164
6165                                         let htlc_sig = htlc_sig_iter.next().unwrap();
6166                                         assert_eq!((htlc_sig.0).0.transaction_output_index, Some($htlc_idx), "output index");
6167
6168                                         let signature = Signature::from_der(&hex::decode($htlc_sig_hex).unwrap()[..]).unwrap();
6169                                         assert_eq!(signature, *(htlc_sig.1).1, "htlc sig");
6170                                         let index = (htlc_sig.1).0;
6171                                         let channel_parameters = chan.channel_transaction_parameters.as_holder_broadcastable();
6172                                         let trusted_tx = holder_commitment_tx.trust();
6173                                         assert_eq!(serialize(&trusted_tx.get_signed_htlc_tx(&channel_parameters, index, &(htlc_sig.0).1, (htlc_sig.1).1, &preimage))[..],
6174                                                         hex::decode($htlc_tx_hex).unwrap()[..], "htlc tx");
6175                                 })*
6176                                 assert!(htlc_sig_iter.next().is_none());
6177                         } }
6178                 }
6179
6180                 // simple commitment tx with no HTLCs
6181                 chan.value_to_self_msat = 7000000000;
6182
6183                 test_commitment!("3045022100c3127b33dcc741dd6b05b1e63cbd1a9a7d816f37af9b6756fa2376b056f032370220408b96279808fe57eb7e463710804cdf4f108388bc5cf722d8c848d2c7f9f3b0",
6184                                                  "30440220616210b2cc4d3afb601013c373bbd8aac54febd9f15400379a8cb65ce7deca60022034236c010991beb7ff770510561ae8dc885b8d38d1947248c38f2ae055647142",
6185                                                  "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", {});
6186
6187                 chan.pending_inbound_htlcs.push({
6188                         let mut out = InboundHTLCOutput{
6189                                 htlc_id: 0,
6190                                 amount_msat: 1000000,
6191                                 cltv_expiry: 500,
6192                                 payment_hash: PaymentHash([0; 32]),
6193                                 state: InboundHTLCState::Committed,
6194                         };
6195                         out.payment_hash.0 = Sha256::hash(&hex::decode("0000000000000000000000000000000000000000000000000000000000000000").unwrap()).into_inner();
6196                         out
6197                 });
6198                 chan.pending_inbound_htlcs.push({
6199                         let mut out = InboundHTLCOutput{
6200                                 htlc_id: 1,
6201                                 amount_msat: 2000000,
6202                                 cltv_expiry: 501,
6203                                 payment_hash: PaymentHash([0; 32]),
6204                                 state: InboundHTLCState::Committed,
6205                         };
6206                         out.payment_hash.0 = Sha256::hash(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()).into_inner();
6207                         out
6208                 });
6209                 chan.pending_outbound_htlcs.push({
6210                         let mut out = OutboundHTLCOutput{
6211                                 htlc_id: 2,
6212                                 amount_msat: 2000000,
6213                                 cltv_expiry: 502,
6214                                 payment_hash: PaymentHash([0; 32]),
6215                                 state: OutboundHTLCState::Committed,
6216                                 source: HTLCSource::dummy(),
6217                         };
6218                         out.payment_hash.0 = Sha256::hash(&hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap()).into_inner();
6219                         out
6220                 });
6221                 chan.pending_outbound_htlcs.push({
6222                         let mut out = OutboundHTLCOutput{
6223                                 htlc_id: 3,
6224                                 amount_msat: 3000000,
6225                                 cltv_expiry: 503,
6226                                 payment_hash: PaymentHash([0; 32]),
6227                                 state: OutboundHTLCState::Committed,
6228                                 source: HTLCSource::dummy(),
6229                         };
6230                         out.payment_hash.0 = Sha256::hash(&hex::decode("0303030303030303030303030303030303030303030303030303030303030303").unwrap()).into_inner();
6231                         out
6232                 });
6233                 chan.pending_inbound_htlcs.push({
6234                         let mut out = InboundHTLCOutput{
6235                                 htlc_id: 4,
6236                                 amount_msat: 4000000,
6237                                 cltv_expiry: 504,
6238                                 payment_hash: PaymentHash([0; 32]),
6239                                 state: InboundHTLCState::Committed,
6240                         };
6241                         out.payment_hash.0 = Sha256::hash(&hex::decode("0404040404040404040404040404040404040404040404040404040404040404").unwrap()).into_inner();
6242                         out
6243                 });
6244
6245                 // commitment tx with all five HTLCs untrimmed (minimum feerate)
6246                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6247                 chan.feerate_per_kw = 0;
6248
6249                 test_commitment!("3044022009b048187705a8cbc9ad73adbe5af148c3d012e1f067961486c822c7af08158c022006d66f3704cfab3eb2dc49dae24e4aa22a6910fc9b424007583204e3621af2e5",
6250                                  "304402206fc2d1f10ea59951eefac0b4b7c396a3c3d87b71ff0b019796ef4535beaf36f902201765b0181e514d04f4c8ad75659d7037be26cdb3f8bb6f78fe61decef484c3ea",
6251                                  "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", {
6252
6253                                   { 0,
6254                                   "3045022100d9e29616b8f3959f1d3d7f7ce893ffedcdc407717d0de8e37d808c91d3a7c50d022078c3033f6d00095c8720a4bc943c1b45727818c082e4e3ddbc6d3116435b624b",
6255                                   "30440220636de5682ef0c5b61f124ec74e8aa2461a69777521d6998295dcea36bc3338110220165285594b23c50b28b82df200234566628a27bcd17f7f14404bd865354eb3ce",
6256                                   "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" },
6257
6258                                   { 1,
6259                                   "30440220649fe8b20e67e46cbb0d09b4acea87dbec001b39b08dee7bdd0b1f03922a8640022037c462dff79df501cecfdb12ea7f4de91f99230bb544726f6e04527b1f896004",
6260                                   "3045022100803159dee7935dba4a1d36a61055ce8fd62caa528573cc221ae288515405a252022029c59e7cffce374fe860100a4a63787e105c3cf5156d40b12dd53ff55ac8cf3f",
6261                                   "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" },
6262
6263                                   { 2,
6264                                   "30440220770fc321e97a19f38985f2e7732dd9fe08d16a2efa4bcbc0429400a447faf49102204d40b417f3113e1b0944ae0986f517564ab4acd3d190503faf97a6e420d43352",
6265                                   "3045022100a437cc2ce77400ecde441b3398fea3c3ad8bdad8132be818227fe3c5b8345989022069d45e7fa0ae551ec37240845e2c561ceb2567eacf3076a6a43a502d05865faa",
6266                                   "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" },
6267
6268                                   { 3,
6269                                   "304402207bcbf4f60a9829b05d2dbab84ed593e0291836be715dc7db6b72a64caf646af802201e489a5a84f7c5cc130398b841d138d031a5137ac8f4c49c770a4959dc3c1363",
6270                                   "304402203121d9b9c055f354304b016a36662ee99e1110d9501cb271b087ddb6f382c2c80220549882f3f3b78d9c492de47543cb9a697cecc493174726146536c5954dac7487",
6271                                   "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" },
6272
6273                                   { 4,
6274                                   "3044022076dca5cb81ba7e466e349b7128cdba216d4d01659e29b96025b9524aaf0d1899022060de85697b88b21c749702b7d2cfa7dfeaa1f472c8f1d7d9c23f2bf968464b87",
6275                                   "3045022100d9080f103cc92bac15ec42464a95f070c7fb6925014e673ee2ea1374d36a7f7502200c65294d22eb20d48564954d5afe04a385551919d8b2ddb4ae2459daaeee1d95",
6276                                   "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" }
6277                 } );
6278
6279                 // commitment tx with seven outputs untrimmed (maximum feerate)
6280                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6281                 chan.feerate_per_kw = 647;
6282
6283                 test_commitment!("3045022100a135f9e8a5ed25f7277446c67956b00ce6f610ead2bdec2c2f686155b7814772022059f1f6e1a8b336a68efcc1af3fe4d422d4827332b5b067501b099c47b7b5b5ee",
6284                                  "30450221009ec15c687898bb4da8b3a833e5ab8bfc51ec6e9202aaa8e66611edfd4a85ed1102203d7183e45078b9735c93450bc3415d3e5a8c576141a711ec6ddcb4a893926bb7",
6285                                  "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", {
6286
6287                                   { 0,
6288                                   "30450221008437627f9ad84ac67052e2a414a4367b8556fd1f94d8b02590f89f50525cd33502205b9c21ff6e7fc864f2352746ad8ba59182510819acb644e25b8a12fc37bbf24f",
6289                                   "30440220344b0deb055230d01703e6c7acd45853c4af2328b49b5d8af4f88a060733406602202ea64f2a43d5751edfe75503cbc35a62e3141b5ed032fa03360faf4ca66f670b",
6290                                   "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" },
6291
6292                                   { 1,
6293                                   "304402205a67f92bf6845cf2892b48d874ac1daf88a36495cf8a06f93d83180d930a6f75022031da1621d95c3f335cc06a3056cf960199dae600b7cf89088f65fc53cdbef28c",
6294                                   "30450221009e5e3822b0185c6799a95288c597b671d6cc69ab80f43740f00c6c3d0752bdda02206da947a74bd98f3175324dc56fdba86cc783703a120a6f0297537e60632f4c7f",
6295                                   "020000000001012cfb3e4788c206881d38f2996b6cb2109b5935acb527d14bdaa7b908afa9b2fe0100000000000000000124060000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e050047304402205a67f92bf6845cf2892b48d874ac1daf88a36495cf8a06f93d83180d930a6f75022031da1621d95c3f335cc06a3056cf960199dae600b7cf89088f65fc53cdbef28c014830450221009e5e3822b0185c6799a95288c597b671d6cc69ab80f43740f00c6c3d0752bdda02206da947a74bd98f3175324dc56fdba86cc783703a120a6f0297537e60632f4c7f01008576a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c820120876475527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae67a914b43e1b38138a41b37f7cd9a1d274bc63e3a9b5d188ac6868f6010000" },
6296
6297                                   { 2,
6298                                   "30440220437e21766054a3eef7f65690c5bcfa9920babbc5af92b819f772f6ea96df6c7402207173622024bd97328cfb26c6665e25c2f5d67c319443ccdc60c903217005d8c8",
6299                                   "3045022100fcfc47e36b712624677626cef3dc1d67f6583bd46926a6398fe6b00b0c9a37760220525788257b187fc775c6370d04eadf34d06f3650a63f8df851cee0ecb47a1673",
6300                                   "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" },
6301
6302                                   { 3,
6303                                   "304402207436e10737e4df499fc051686d3e11a5bb2310e4d1f1e691d287cef66514791202207cb58e71a6b7a42dd001b7e3ae672ea4f71ea3e1cd412b742e9124abb0739c64",
6304                                   "3045022100e78211b8409afb7255ffe37337da87f38646f1faebbdd61bc1920d69e3ead67a02201a626305adfcd16bfb7e9340928d9b6305464eab4aa4c4a3af6646e9b9f69dee",
6305                                   "020000000001012cfb3e4788c206881d38f2996b6cb2109b5935acb527d14bdaa7b908afa9b2fe030000000000000000010c0a0000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e050047304402207436e10737e4df499fc051686d3e11a5bb2310e4d1f1e691d287cef66514791202207cb58e71a6b7a42dd001b7e3ae672ea4f71ea3e1cd412b742e9124abb0739c6401483045022100e78211b8409afb7255ffe37337da87f38646f1faebbdd61bc1920d69e3ead67a02201a626305adfcd16bfb7e9340928d9b6305464eab4aa4c4a3af6646e9b9f69dee01008576a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c820120876475527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae67a9148a486ff2e31d6158bf39e2608864d63fefd09d5b88ac6868f7010000" },
6306
6307                                   { 4,
6308                                   "30450221009acd6a827a76bfee50806178dfe0495cd4e1d9c58279c194c7b01520fe68cb8d022024d439047c368883e570997a7d40f0b430cb5a742f507965e7d3063ae3feccca",
6309                                   "3044022048762cf546bbfe474f1536365ea7c416e3c0389d60558bc9412cb148fb6ab68202207215d7083b75c96ff9d2b08c59c34e287b66820f530b486a9aa4cdd9c347d5b9",
6310                                   "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" }
6311                 } );
6312
6313                 // commitment tx with six outputs untrimmed (minimum feerate)
6314                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6315                 chan.feerate_per_kw = 648;
6316
6317                 test_commitment!("304402203948f900a5506b8de36a4d8502f94f21dd84fd9c2314ab427d52feaa7a0a19f2022059b6a37a4adaa2c5419dc8aea63c6e2a2ec4c4bde46207f6dc1fcd22152fc6e5",
6318                                  "3045022100b15f72908ba3382a34ca5b32519240a22300cc6015b6f9418635fb41f3d01d8802207adb331b9ed1575383dca0f2355e86c173802feecf8298fbea53b9d4610583e9",
6319                                  "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", {
6320
6321                                   { 0,
6322                                   "3045022100a031202f3be94678f0e998622ee95ebb6ada8da1e9a5110228b5e04a747351e4022010ca6a21e18314ed53cfaae3b1f51998552a61a468e596368829a50ce40110e0",
6323                                   "304502210097e1873b57267730154595187a34949d3744f52933070c74757005e61ce2112e02204ecfba2aa42d4f14bdf8bad4206bb97217b702e6c433e0e1b0ce6587e6d46ec6",
6324                                   "020000000001010f44041fdfba175987cf4e6135ba2a154e3b7fb96483dc0ed5efc0678e5b6bf10000000000000000000123060000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e0500483045022100a031202f3be94678f0e998622ee95ebb6ada8da1e9a5110228b5e04a747351e4022010ca6a21e18314ed53cfaae3b1f51998552a61a468e596368829a50ce40110e00148304502210097e1873b57267730154595187a34949d3744f52933070c74757005e61ce2112e02204ecfba2aa42d4f14bdf8bad4206bb97217b702e6c433e0e1b0ce6587e6d46ec601008576a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c820120876475527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae67a914b43e1b38138a41b37f7cd9a1d274bc63e3a9b5d188ac6868f6010000" },
6325
6326                                   { 1,
6327                                   "304402202361012a634aee7835c5ecdd6413dcffa8f404b7e77364c792cff984e4ee71e90220715c5e90baa08daa45a7439b1ee4fa4843ed77b19c058240b69406606d384124",
6328                                   "3044022019de73b00f1d818fb388e83b2c8c31f6bce35ac624e215bc12f88f9dc33edf48022006ff814bb9f700ee6abc3294e146fac3efd4f13f0005236b41c0a946ee00c9ae",
6329                                   "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" },
6330
6331                                   { 2,
6332                                   "304402207e8e82cd71ed4febeb593732c260456836e97d81896153ecd2b3cf320ca6861702202dd4a30f68f98ced7cc56a36369ac1fdd978248c5ff4ed204fc00cc625532989",
6333                                   "3045022100bd0be6100c4fd8f102ec220e1b053e4c4e2ecca25615490150007b40d314dc3902201a1e0ea266965b43164d9e6576f58fa6726d42883dd1c3996d2925c2e2260796",
6334                                   "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" },
6335
6336                                   { 3,
6337                                   "3044022024cd52e4198c8ae0e414a86d86b5a65ea7450f2eb4e783096736d93395eca5ce022078f0094745b45be4d4b2b04dd5978c9e66ba49109e5704403e84aaf5f387d6be",
6338                                   "3045022100bbfb9d0a946d420807c86e985d636cceb16e71c3694ed186316251a00cbd807202207773223f9a337e145f64673825be9b30d07ef1542c82188b264bedcf7cda78c6",
6339                                   "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" }
6340                 } );
6341
6342                 // commitment tx with six outputs untrimmed (maximum feerate)
6343                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6344                 chan.feerate_per_kw = 2069;
6345
6346                 test_commitment!("304502210090b96a2498ce0c0f2fadbec2aab278fed54c1a7838df793ec4d2c78d96ec096202204fdd439c50f90d483baa7b68feeef4bd33bc277695405447bcd0bfb2ca34d7bc",
6347                                  "3045022100ad9a9bbbb75d506ca3b716b336ee3cf975dd7834fcf129d7dd188146eb58a8b4022061a759ee417339f7fe2ea1e8deb83abb6a74db31a09b7648a932a639cda23e33",
6348                                  "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", {
6349
6350                                   { 0,
6351                                   "3045022100f33513ee38abf1c582876f921f8fddc06acff48e04515532a32d3938de938ffd02203aa308a2c1863b7d6fdf53159a1465bf2e115c13152546cc5d74483ceaa7f699",
6352                                   "3045022100a637902a5d4c9ba9e7c472a225337d5aac9e2e3f6744f76e237132e7619ba0400220035c60d784a031c0d9f6df66b7eab8726a5c25397399ee4aa960842059eb3f9d",
6353                                   "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" },
6354
6355                                   { 1,
6356                                   "3045022100ce07682cf4b90093c22dc2d9ab2a77ad6803526b655ef857221cc96af5c9e0bf02200f501cee22e7a268af40b555d15a8237c9f36ad67ef1841daf9f6a0267b1e6df",
6357                                   "3045022100e57e46234f8782d3ff7aa593b4f7446fb5316c842e693dc63ee324fd49f6a1c302204a2f7b44c48bd26e1554422afae13153eb94b29d3687b733d18930615fb2db61",
6358                                   "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" },
6359
6360                                   { 2,
6361                                   "3045022100e3e35492e55f82ec0bc2f317ffd7a486d1f7024330fe9743c3559fc39f32ef0c02203d1d4db651fc388a91d5ad8ecdd8e83673063bc8eefe27cfd8c189090e3a23e0",
6362                                   "3044022068613fb1b98eb3aec7f44c5b115b12343c2f066c4277c82b5f873dfe68f37f50022028109b4650f3f528ca4bfe9a467aff2e3e43893b61b5159157119d5d95cf1c18",
6363                                   "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" },
6364
6365                                   { 3,
6366                                   "304402207475aeb0212ef9bf5130b60937817ad88c9a87976988ef1f323f026148cc4a850220739fea17ad3257dcad72e509c73eebe86bee30b178467b9fdab213d631b109df",
6367                                   "3045022100d315522e09e7d53d2a659a79cb67fef56d6c4bddf3f46df6772d0d20a7beb7c8022070bcc17e288607b6a72be0bd83368bb6d53488db266c1cdb4d72214e4f02ac33",
6368                                   "02000000000101adbe717a63fb658add30ada1e6e12ed257637581898abe475c11d7bbcd65bd4d03000000000000000001f2090000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e050047304402207475aeb0212ef9bf5130b60937817ad88c9a87976988ef1f323f026148cc4a850220739fea17ad3257dcad72e509c73eebe86bee30b178467b9fdab213d631b109df01483045022100d315522e09e7d53d2a659a79cb67fef56d6c4bddf3f46df6772d0d20a7beb7c8022070bcc17e288607b6a72be0bd83368bb6d53488db266c1cdb4d72214e4f02ac33012004040404040404040404040404040404040404040404040404040404040404048a76a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c8201208763a91418bc1a114ccf9c052d3d23e28d3b0a9d1227434288527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae677502f801b175ac686800000000" }
6369                 } );
6370
6371                 // commitment tx with five outputs untrimmed (minimum feerate)
6372                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6373                 chan.feerate_per_kw = 2070;
6374
6375                 test_commitment!("304402204ca1ba260dee913d318271d86e10ca0f5883026fb5653155cff600fb40895223022037b145204b7054a40e08bb1fefbd826f827b40838d3e501423bcc57924bcb50c",
6376                                  "3044022001014419b5ba00e083ac4e0a85f19afc848aacac2d483b4b525d15e2ae5adbfe022015ebddad6ee1e72b47cb09f3e78459da5be01ccccd95dceca0e056a00cc773c1",
6377                                  "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", {
6378
6379                                   { 0,
6380                                   "304402205f6b6d12d8d2529fb24f4445630566cf4abbd0f9330ab6c2bdb94222d6a2a0c502202f556258ae6f05b193749e4c541dfcc13b525a5422f6291f073f15617ba8579b",
6381                                   "30440220150b11069454da70caf2492ded9e0065c9a57f25ac2a4c52657b1d15b6c6ed85022068a38833b603c8892717206383611bad210f1cbb4b1f87ea29c6c65b9e1cb3e5",
6382                                   "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" },
6383
6384                                   { 1,
6385                                   "3045022100f960dfb1c9aee7ce1437efa65b523e399383e8149790e05d8fed27ff6e42fe0002202fe8613e062ffe0b0c518cc4101fba1c6de70f64a5bcc7ae663f2efae43b8546",
6386                                   "30450221009a6ed18e6873bc3644332a6ee21c152a5b102821865350df7a8c74451a51f9f2022050d801fb4895d7d7fbf452824c0168347f5c0cbe821cf6a97a63af5b8b2563c6",
6387                                   "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" },
6388
6389                                   { 2,
6390                                   "3045022100ae5fc7717ae684bc1fcf9020854e5dbe9842c9e7472879ac06ff95ac2bb10e4e022057728ada4c00083a3e65493fb5d50a232165948a1a0f530ef63185c2c8c56504",
6391                                   "30440220408ad3009827a8fccf774cb285587686bfb2ed041f89a89453c311ce9c8ee0f902203c7392d9f8306d3a46522a66bd2723a7eb2628cb2d9b34d4c104f1766bf37502",
6392                                   "02000000000101403ad7602b43293497a3a2235a12ecefda4f3a1f1d06e49b1786d945685de1ff02000000000000000001f1090000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e0500483045022100ae5fc7717ae684bc1fcf9020854e5dbe9842c9e7472879ac06ff95ac2bb10e4e022057728ada4c00083a3e65493fb5d50a232165948a1a0f530ef63185c2c8c56504014730440220408ad3009827a8fccf774cb285587686bfb2ed041f89a89453c311ce9c8ee0f902203c7392d9f8306d3a46522a66bd2723a7eb2628cb2d9b34d4c104f1766bf37502012004040404040404040404040404040404040404040404040404040404040404048a76a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c8201208763a91418bc1a114ccf9c052d3d23e28d3b0a9d1227434288527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae677502f801b175ac686800000000" }
6393                 } );
6394
6395                 // commitment tx with five outputs untrimmed (maximum feerate)
6396                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6397                 chan.feerate_per_kw = 2194;
6398
6399                 test_commitment!("304402204bb3d6e279d71d9da414c82de42f1f954267c762b2e2eb8b76bc3be4ea07d4b0022014febc009c5edc8c3fc5d94015de163200f780046f1c293bfed8568f08b70fb3",
6400                                  "3044022072c2e2b1c899b2242656a537dde2892fa3801be0d6df0a87836c550137acde8302201654aa1974d37a829083c3ba15088689f30b56d6a4f6cb14c7bad0ee3116d398",
6401                                  "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", {
6402
6403                                   { 0,
6404                                   "3045022100939726680351a7856c1bc386d4a1f422c7d29bd7b56afc139570f508474e6c40022023175a799ccf44c017fbaadb924c40b2a12115a5b7d0dfd3228df803a2de8450",
6405                                   "304502210099c98c2edeeee6ec0fb5f3bea8b79bb016a2717afa9b5072370f34382de281d302206f5e2980a995e045cf90a547f0752a7ee99d48547bc135258fe7bc07e0154301",
6406                                   "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" },
6407
6408                                   { 1,
6409                                   "3044022021bb883bf324553d085ba2e821cad80c28ef8b303dbead8f98e548783c02d1600220638f9ef2a9bba25869afc923f4b5dc38be3bb459f9efa5d869392d5f7779a4a0",
6410                                   "3045022100fd85bd7697b89c08ec12acc8ba89b23090637d83abd26ca37e01ae93e67c367302202b551fe69386116c47f984aab9c8dfd25d864dcde5d3389cfbef2447a85c4b77",
6411                                   "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" },
6412
6413                                   { 2,
6414                                   "3045022100c9e6f0454aa598b905a35e641a70cc9f67b5f38cc4b00843a041238c4a9f1c4a0220260a2822a62da97e44583e837245995ca2e36781769c52f19e498efbdcca262b",
6415                                   "30450221008a9f2ea24cd455c2b64c1472a5fa83865b0a5f49a62b661801e884cf2849af8302204d44180e50bf6adfcf1c1e581d75af91aba4e28681ce4a5ee5f3cbf65eca10f3",
6416                                   "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" }
6417                 } );
6418
6419                 // commitment tx with four outputs untrimmed (minimum feerate)
6420                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6421                 chan.feerate_per_kw = 2195;
6422
6423                 test_commitment!("304402201a8c1b1f9671cd9e46c7323a104d7047cc48d3ee80d40d4512e0c72b8dc65666022066d7f9a2ce18c9eb22d2739ffcce05721c767f9b607622a31b6ea5793ddce403",
6424                                  "3044022044d592025b610c0d678f65032e87035cdfe89d1598c522cc32524ae8172417c30220749fef9d5b2ae8cdd91ece442ba8809bc891efedae2291e578475f97715d1767",
6425                                  "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", {
6426
6427                                   { 0,
6428                                   "3045022100e57b845066a06ee7c2cbfc29eabffe52daa9bf6f6de760066d04df9f9b250e0002202ffb197f0e6e0a77a75a9aff27014bd3de83b7f748d7efef986abe655e1dd50e",
6429                                   "3045022100ecc8c6529d0b2316d046f0f0757c1e1c25a636db168ec4f3aa1b9278df685dc0022067ae6b65e936f1337091f7b18a15935b608c5f2cdddb2f892ed0babfdd376d76",
6430                                   "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" },
6431
6432                                   { 1,
6433                                   "3045022100d193b7ecccad8057571620a0b1ffa6c48e9483311723b59cf536043b20bc51550220546d4bd37b3b101ecda14f6c907af46ec391abce1cd9c7ce22b1a62b534f2f2a",
6434                                   "3044022014d66f11f9cacf923807eba49542076c5fe5cccf252fb08fe98c78ef3ca6ab5402201b290dbe043cc512d9d78de074a5a129b8759bc6a6c546b190d120b690bd6e82",
6435                                   "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" }
6436                 } );
6437
6438                 // commitment tx with four outputs untrimmed (maximum feerate)
6439                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6440                 chan.feerate_per_kw = 3702;
6441
6442                 test_commitment!("304502210092a587aeb777f869e7ff0d7898ea619ee26a3dacd1f3672b945eea600be431100220077ee9eae3528d15251f2a52b607b189820e57a6ccfac8d1af502b132ee40169",
6443                                  "3045022100e5efb73c32d32da2d79702299b6317de6fb24a60476e3855926d78484dd1b3c802203557cb66a42c944ef06e00bcc4da35a5bcb2f185aab0f8e403e519e1d66aaf75",
6444                                  "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", {
6445
6446                                   { 0,
6447                                   "304402206fa54c11f98c3bae1e93df43fc7affeb05b476bf8060c03e29c377c69bc08e8b0220672701cce50d5c379ff45a5d2cfe48ac44973adb066ac32608e21221d869bb89",
6448                                   "304402206e36c683ebf2cb16bcef3d5439cf8b53cd97280a365ed8acd7abb85a8ba5f21c02206e8621edfc2a5766cbc96eb67fd501127ff163eb6b85518a39f7d4974aef126f",
6449                                   "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" },
6450
6451                                   { 1,
6452                                   "3044022057649739b0eb74d541ead0dfdb3d4b2c15aa192720031044c3434c67812e5ca902201e5ede42d960ae551707f4a6b34b09393cf4dee2418507daa022e3550dbb5817",
6453                                   "304402207faad26678c8850e01b4a0696d60841f7305e1832b786110ee9075cb92ed14a30220516ef8ee5dfa80824ea28cbcec0dd95f8b847146257c16960db98507db15ffdc",
6454                                   "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" }
6455                 } );
6456
6457                 // commitment tx with three outputs untrimmed (minimum feerate)
6458                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6459                 chan.feerate_per_kw = 3703;
6460
6461                 test_commitment!("3045022100b495d239772a237ff2cf354b1b11be152fd852704cb184e7356d13f2fb1e5e430220723db5cdb9cbd6ead7bfd3deb419cf41053a932418cbb22a67b581f40bc1f13e",
6462                                  "304402201b736d1773a124c745586217a75bed5f66c05716fbe8c7db4fdb3c3069741cdd02205083f39c321c1bcadfc8d97e3c791a66273d936abac0c6a2fde2ed46019508e1",
6463                                  "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", {
6464
6465                                   { 0,
6466                                   "3045022100c34c61735f93f2e324cc873c3b248111ccf8f6db15d5969583757010d4ad2b4602207867bb919b2ddd6387873e425345c9b7fd18d1d66aba41f3607bc2896ef3c30a",
6467                                   "3045022100988c143e2110067117d2321bdd4bd16ca1734c98b29290d129384af0962b634e02206c1b02478878c5f547018b833986578f90c3e9be669fe5788ad0072a55acbb05",
6468                                   "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" }
6469                 } );
6470
6471                 // commitment tx with three outputs untrimmed (maximum feerate)
6472                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6473                 chan.feerate_per_kw = 4914;
6474
6475                 test_commitment!("3045022100b4b16d5f8cc9fc4c1aff48831e832a0d8990e133978a66e302c133550954a44d022073573ce127e2200d316f6b612803a5c0c97b8d20e1e44dbe2ac0dd2fb8c95244",
6476                                  "3045022100d72638bc6308b88bb6d45861aae83e5b9ff6e10986546e13bce769c70036e2620220320be7c6d66d22f30b9fcd52af66531505b1310ca3b848c19285b38d8a1a8c19",
6477                                  "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", {
6478
6479                                   { 0,
6480                                   "3045022100f43591c156038ba217756006bb3c55f7d113a325cdd7d9303c82115372858d68022016355b5aadf222bc8d12e426c75f4a03423917b2443a103eb2a498a3a2234374",
6481                                   "30440220585dee80fafa264beac535c3c0bb5838ac348b156fdc982f86adc08dfc9bfd250220130abb82f9f295cc9ef423dcfef772fde2acd85d9df48cc538981d26a10a9c10",
6482                                   "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" }
6483                 } );
6484
6485                 // commitment tx with two outputs untrimmed (minimum feerate)
6486                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6487                 chan.feerate_per_kw = 4915;
6488
6489                 test_commitment!("304402203a286936e74870ca1459c700c71202af0381910a6bfab687ef494ef1bc3e02c902202506c362d0e3bee15e802aa729bf378e051644648253513f1c085b264cc2a720",
6490                                  "30450221008a953551f4d67cb4df3037207fc082ddaf6be84d417b0bd14c80aab66f1b01a402207508796dc75034b2dee876fe01dc05a08b019f3e5d689ac8842ade2f1befccf5",
6491                                  "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", {});
6492
6493                 // commitment tx with two outputs untrimmed (maximum feerate)
6494                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6495                 chan.feerate_per_kw = 9651180;
6496
6497                 test_commitment!("304402200a8544eba1d216f5c5e530597665fa9bec56943c0f66d98fc3d028df52d84f7002201e45fa5c6bc3a506cc2553e7d1c0043a9811313fc39c954692c0d47cfce2bbd3",
6498                                  "3045022100e11b638c05c650c2f63a421d36ef8756c5ce82f2184278643520311cdf50aa200220259565fb9c8e4a87ccaf17f27a3b9ca4f20625754a0920d9c6c239d8156a11de",
6499                                  "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", {});
6500
6501                 // commitment tx with one output untrimmed (minimum feerate)
6502                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6503                 chan.feerate_per_kw = 9651181;
6504
6505                 test_commitment!("304402202ade0142008309eb376736575ad58d03e5b115499709c6db0b46e36ff394b492022037b63d78d66404d6504d4c4ac13be346f3d1802928a6d3ad95a6a944227161a2",
6506                                  "304402207e8d51e0c570a5868a78414f4e0cbfaed1106b171b9581542c30718ee4eb95ba02203af84194c97adf98898c9afe2f2ed4a7f8dba05a2dfab28ac9d9c604aa49a379",
6507                                  "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", {});
6508
6509                 // commitment tx with fee greater than funder amount
6510                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6511                 chan.feerate_per_kw = 9651936;
6512
6513                 test_commitment!("304402202ade0142008309eb376736575ad58d03e5b115499709c6db0b46e36ff394b492022037b63d78d66404d6504d4c4ac13be346f3d1802928a6d3ad95a6a944227161a2",
6514                                  "304402207e8d51e0c570a5868a78414f4e0cbfaed1106b171b9581542c30718ee4eb95ba02203af84194c97adf98898c9afe2f2ed4a7f8dba05a2dfab28ac9d9c604aa49a379",
6515                                  "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", {});
6516
6517                 // commitment tx with 3 htlc outputs, 2 offered having the same amount and preimage
6518                 chan.value_to_self_msat = 7_000_000_000 - 2_000_000;
6519                 chan.feerate_per_kw = 253;
6520                 chan.pending_inbound_htlcs.clear();
6521                 chan.pending_inbound_htlcs.push({
6522                         let mut out = InboundHTLCOutput{
6523                                 htlc_id: 1,
6524                                 amount_msat: 2000000,
6525                                 cltv_expiry: 501,
6526                                 payment_hash: PaymentHash([0; 32]),
6527                                 state: InboundHTLCState::Committed,
6528                         };
6529                         out.payment_hash.0 = Sha256::hash(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()).into_inner();
6530                         out
6531                 });
6532                 chan.pending_outbound_htlcs.clear();
6533                 chan.pending_outbound_htlcs.push({
6534                         let mut out = OutboundHTLCOutput{
6535                                 htlc_id: 6,
6536                                 amount_msat: 5000000,
6537                                 cltv_expiry: 506,
6538                                 payment_hash: PaymentHash([0; 32]),
6539                                 state: OutboundHTLCState::Committed,
6540                                 source: HTLCSource::dummy(),
6541                         };
6542                         out.payment_hash.0 = Sha256::hash(&hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()).into_inner();
6543                         out
6544                 });
6545                 chan.pending_outbound_htlcs.push({
6546                         let mut out = OutboundHTLCOutput{
6547                                 htlc_id: 5,
6548                                 amount_msat: 5000000,
6549                                 cltv_expiry: 505,
6550                                 payment_hash: PaymentHash([0; 32]),
6551                                 state: OutboundHTLCState::Committed,
6552                                 source: HTLCSource::dummy(),
6553                         };
6554                         out.payment_hash.0 = Sha256::hash(&hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()).into_inner();
6555                         out
6556                 });
6557
6558                 test_commitment!("30440220048705bec5288d28b3f29344b8d124853b1af423a568664d2c6f02c8ea886525022060f998a461052a2476b912db426ea2a06700953a241135c7957f2e79bc222df9",
6559                                  "3045022100c4f1d60b6fca9febc8b39de1a31e84c5f7c4b41c97239ef05f4350aa484c6b5e02200c5134ac8b20eb7a29d0dd4a501f6aa8fefb8489171f4cb408bd2a32324ab03f",
6560                                  "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", {
6561
6562                                   { 0,
6563                                   "304502210081cbb94121761d34c189cd4e6a281feea6f585060ad0ba2632e8d6b3c6bb8a6c02201007981bbd16539d63df2805b5568f1f5688cd2a885d04706f50db9b77ba13c6",
6564                                   "304502210090ed76aeb21b53236a598968abc66e2024691d07b62f53ddbeca8f93144af9c602205f873af5a0c10e62690e9aba09740550f194a9dc455ba4c1c23f6cde7704674c",
6565                                   "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" },
6566                                   { 1,
6567                                   "304402201d0f09d2bf7bc245a4f17980e1e9164290df16c70c6a2ff1592f5030d6108581022061e744a7dc151b36bf0aff7a4f1812ba90b8b03633bb979a270d19858fd960c5",
6568                                   "30450221009aef000d2e843a4202c1b1a2bf554abc9a7902bf49b2cb0759bc507456b7ebad02204e7c3d193ede2fd2b4cd6b39f51a920e581e35575e357e44d7b699c40ce61d39",
6569                                   "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" },
6570                                   { 2,
6571                                   "30440220010bf035d5823596e50dce2076a4d9f942d8d28031c9c428b901a02b6b8140de02203250e8e4a08bc5b4ecdca4d0eedf98223e02e3ac1c0206b3a7ffdb374aa21e5f",
6572                                   "30440220073de0067b88e425b3018b30366bfeda0ccb703118ccd3d02ead08c0f53511d002203fac50ac0e4cf8a3af0b4b1b12e801650591f748f8ddf1e089c160f10b69e511",
6573                                   "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" }
6574                 } );
6575         }
6576
6577         #[test]
6578         fn test_per_commitment_secret_gen() {
6579                 // Test vectors from BOLT 3 Appendix D:
6580
6581                 let mut seed = [0; 32];
6582                 seed[0..32].clone_from_slice(&hex::decode("0000000000000000000000000000000000000000000000000000000000000000").unwrap());
6583                 assert_eq!(chan_utils::build_commitment_secret(&seed, 281474976710655),
6584                            hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap()[..]);
6585
6586                 seed[0..32].clone_from_slice(&hex::decode("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF").unwrap());
6587                 assert_eq!(chan_utils::build_commitment_secret(&seed, 281474976710655),
6588                            hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap()[..]);
6589
6590                 assert_eq!(chan_utils::build_commitment_secret(&seed, 0xaaaaaaaaaaa),
6591                            hex::decode("56f4008fb007ca9acf0e15b054d5c9fd12ee06cea347914ddbaed70d1c13a528").unwrap()[..]);
6592
6593                 assert_eq!(chan_utils::build_commitment_secret(&seed, 0x555555555555),
6594                            hex::decode("9015daaeb06dba4ccc05b91b2f73bd54405f2be9f217fbacd3c5ac2e62327d31").unwrap()[..]);
6595
6596                 seed[0..32].clone_from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap());
6597                 assert_eq!(chan_utils::build_commitment_secret(&seed, 1),
6598                            hex::decode("915c75942a26bb3a433a8ce2cb0427c29ec6c1775cfc78328b57f6ba7bfeaa9c").unwrap()[..]);
6599         }
6600
6601         #[test]
6602         fn test_key_derivation() {
6603                 // Test vectors from BOLT 3 Appendix E:
6604                 let secp_ctx = Secp256k1::new();
6605
6606                 let base_secret = SecretKey::from_slice(&hex::decode("000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f").unwrap()[..]).unwrap();
6607                 let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
6608
6609                 let base_point = PublicKey::from_secret_key(&secp_ctx, &base_secret);
6610                 assert_eq!(base_point.serialize()[..], hex::decode("036d6caac248af96f6afa7f904f550253a0f3ef3f5aa2fe6838a95b216691468e2").unwrap()[..]);
6611
6612                 let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
6613                 assert_eq!(per_commitment_point.serialize()[..], hex::decode("025f7117a78150fe2ef97db7cfc83bd57b2e2c0d0dd25eaf467a4a1c2a45ce1486").unwrap()[..]);
6614
6615                 assert_eq!(chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &base_point).unwrap().serialize()[..],
6616                                 hex::decode("0235f2dbfaa89b57ec7b055afe29849ef7ddfeb1cefdb9ebdc43f5494984db29e5").unwrap()[..]);
6617
6618                 assert_eq!(chan_utils::derive_private_key(&secp_ctx, &per_commitment_point, &base_secret).unwrap(),
6619                                 SecretKey::from_slice(&hex::decode("cbced912d3b21bf196a766651e436aff192362621ce317704ea2f75d87e7be0f").unwrap()[..]).unwrap());
6620
6621                 assert_eq!(chan_utils::derive_public_revocation_key(&secp_ctx, &per_commitment_point, &base_point).unwrap().serialize()[..],
6622                                 hex::decode("02916e326636d19c33f13e8c0c3a03dd157f332f3e99c317c141dd865eb01f8ff0").unwrap()[..]);
6623
6624                 assert_eq!(chan_utils::derive_private_revocation_key(&secp_ctx, &per_commitment_secret, &base_secret).unwrap(),
6625                                 SecretKey::from_slice(&hex::decode("d09ffff62ddb2297ab000cc85bcb4283fdeb6aa052affbc9dddcf33b61078110").unwrap()[..]).unwrap());
6626         }
6627 }