Rename MIN_DUST_LIMIT_SATOSHIS constant to disambiguate chan vs P2P
[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, 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, HTLC_FAIL_BACK_BUFFER};
36 use chain::transaction::{OutPoint, TransactionData};
37 use chain::keysinterface::{Sign, KeysInterface};
38 use util::ser::{Readable, ReadableArgs, Writeable, Writer, VecWriter};
39 use util::logger::Logger;
40 use util::errors::APIError;
41 use util::config::{UserConfig,ChannelConfig};
42 use util::scid_utils::scid_from_parts;
43
44 use io;
45 use prelude::*;
46 use core::{cmp,mem,fmt};
47 use core::ops::Deref;
48 #[cfg(any(test, feature = "fuzztarget", debug_assertions))]
49 use sync::Mutex;
50 use bitcoin::hashes::hex::ToHex;
51
52 #[cfg(test)]
53 pub struct ChannelValueStat {
54         pub value_to_self_msat: u64,
55         pub channel_value_msat: u64,
56         pub channel_reserve_msat: u64,
57         pub pending_outbound_htlcs_amount_msat: u64,
58         pub pending_inbound_htlcs_amount_msat: u64,
59         pub holding_cell_outbound_amount_msat: u64,
60         pub counterparty_max_htlc_value_in_flight_msat: u64, // outgoing
61         pub counterparty_dust_limit_msat: u64,
62 }
63
64 #[derive(Clone, Copy, PartialEq)]
65 enum FeeUpdateState {
66         // Inbound states mirroring InboundHTLCState
67         RemoteAnnounced,
68         AwaitingRemoteRevokeToAnnounce,
69         // Note that we do not have a AwaitingAnnouncedRemoteRevoke variant here as it is universally
70         // handled the same as `Committed`, with the only exception in `InboundHTLCState` being the
71         // distinction of when we allow ourselves to forward the HTLC. Because we aren't "forwarding"
72         // the fee update anywhere, we can simply consider the fee update `Committed` immediately
73         // instead of setting it to AwaitingAnnouncedRemoteRevoke.
74
75         // Outbound state can only be `LocalAnnounced` or `Committed`
76         Outbound,
77 }
78
79 enum InboundHTLCRemovalReason {
80         FailRelay(msgs::OnionErrorPacket),
81         FailMalformed(([u8; 32], u16)),
82         Fulfill(PaymentPreimage),
83 }
84
85 enum InboundHTLCState {
86         /// Offered by remote, to be included in next local commitment tx. I.e., the remote sent an
87         /// update_add_htlc message for this HTLC.
88         RemoteAnnounced(PendingHTLCStatus),
89         /// Included in a received commitment_signed message (implying we've
90         /// revoke_and_ack'd it), but the remote hasn't yet revoked their previous
91         /// state (see the example below). We have not yet included this HTLC in a
92         /// commitment_signed message because we are waiting on the remote's
93         /// aforementioned state revocation. One reason this missing remote RAA
94         /// (revoke_and_ack) blocks us from constructing a commitment_signed message
95         /// is because every time we create a new "state", i.e. every time we sign a
96         /// new commitment tx (see [BOLT #2]), we need a new per_commitment_point,
97         /// which are provided one-at-a-time in each RAA. E.g., the last RAA they
98         /// sent provided the per_commitment_point for our current commitment tx.
99         /// The other reason we should not send a commitment_signed without their RAA
100         /// is because their RAA serves to ACK our previous commitment_signed.
101         ///
102         /// Here's an example of how an HTLC could come to be in this state:
103         /// remote --> update_add_htlc(prev_htlc)   --> local
104         /// remote --> commitment_signed(prev_htlc) --> local
105         /// remote <-- revoke_and_ack               <-- local
106         /// remote <-- commitment_signed(prev_htlc) <-- local
107         /// [note that here, the remote does not respond with a RAA]
108         /// remote --> update_add_htlc(this_htlc)   --> local
109         /// remote --> commitment_signed(prev_htlc, this_htlc) --> local
110         /// Now `this_htlc` will be assigned this state. It's unable to be officially
111         /// accepted, i.e. included in a commitment_signed, because we're missing the
112         /// RAA that provides our next per_commitment_point. The per_commitment_point
113         /// is used to derive commitment keys, which are used to construct the
114         /// signatures in a commitment_signed message.
115         /// Implies AwaitingRemoteRevoke.
116         ///
117         /// [BOLT #2]: https://github.com/lightningnetwork/lightning-rfc/blob/master/02-peer-protocol.md
118         AwaitingRemoteRevokeToAnnounce(PendingHTLCStatus),
119         /// Included in a received commitment_signed message (implying we've revoke_and_ack'd it).
120         /// We have also included this HTLC in our latest commitment_signed and are now just waiting
121         /// on the remote's revoke_and_ack to make this HTLC an irrevocable part of the state of the
122         /// channel (before it can then get forwarded and/or removed).
123         /// Implies AwaitingRemoteRevoke.
124         AwaitingAnnouncedRemoteRevoke(PendingHTLCStatus),
125         Committed,
126         /// Removed by us and a new commitment_signed was sent (if we were AwaitingRemoteRevoke when we
127         /// created it we would have put it in the holding cell instead). When they next revoke_and_ack
128         /// we'll drop it.
129         /// Note that we have to keep an eye on the HTLC until we've received a broadcastable
130         /// commitment transaction without it as otherwise we'll have to force-close the channel to
131         /// claim it before the timeout (obviously doesn't apply to revoked HTLCs that we can't claim
132         /// anyway). That said, ChannelMonitor does this for us (see
133         /// ChannelMonitor::should_broadcast_holder_commitment_txn) so we actually remove the HTLC from
134         /// our own local state before then, once we're sure that the next commitment_signed and
135         /// ChannelMonitor::provide_latest_local_commitment_tx will not include this HTLC.
136         LocalRemoved(InboundHTLCRemovalReason),
137 }
138
139 struct InboundHTLCOutput {
140         htlc_id: u64,
141         amount_msat: u64,
142         cltv_expiry: u32,
143         payment_hash: PaymentHash,
144         state: InboundHTLCState,
145 }
146
147 enum OutboundHTLCState {
148         /// Added by us and included in a commitment_signed (if we were AwaitingRemoteRevoke when we
149         /// created it we would have put it in the holding cell instead). When they next revoke_and_ack
150         /// we will promote to Committed (note that they may not accept it until the next time we
151         /// revoke, but we don't really care about that:
152         ///  * they've revoked, so worst case we can announce an old state and get our (option on)
153         ///    money back (though we won't), and,
154         ///  * we'll send them a revoke when they send a commitment_signed, and since only they're
155         ///    allowed to remove it, the "can only be removed once committed on both sides" requirement
156         ///    doesn't matter to us and it's up to them to enforce it, worst-case they jump ahead but
157         ///    we'll never get out of sync).
158         /// Note that we Box the OnionPacket as it's rather large and we don't want to blow up
159         /// OutboundHTLCOutput's size just for a temporary bit
160         LocalAnnounced(Box<msgs::OnionPacket>),
161         Committed,
162         /// Remote removed this (outbound) HTLC. We're waiting on their commitment_signed to finalize
163         /// the change (though they'll need to revoke before we fail the payment).
164         RemoteRemoved(Option<HTLCFailReason>),
165         /// Remote removed this and sent a commitment_signed (implying we've revoke_and_ack'ed it), but
166         /// the remote side hasn't yet revoked their previous state, which we need them to do before we
167         /// can do any backwards failing. Implies AwaitingRemoteRevoke.
168         /// We also have not yet removed this HTLC in a commitment_signed message, and are waiting on a
169         /// remote revoke_and_ack on a previous state before we can do so.
170         AwaitingRemoteRevokeToRemove(Option<HTLCFailReason>),
171         /// Remote removed this and sent a commitment_signed (implying we've revoke_and_ack'ed it), but
172         /// the remote side hasn't yet revoked their previous state, which we need them to do before we
173         /// can do any backwards failing. Implies AwaitingRemoteRevoke.
174         /// We have removed this HTLC in our latest commitment_signed and are now just waiting on a
175         /// revoke_and_ack to drop completely.
176         AwaitingRemovedRemoteRevoke(Option<HTLCFailReason>),
177 }
178
179 struct OutboundHTLCOutput {
180         htlc_id: u64,
181         amount_msat: u64,
182         cltv_expiry: u32,
183         payment_hash: PaymentHash,
184         state: OutboundHTLCState,
185         source: HTLCSource,
186 }
187
188 /// See AwaitingRemoteRevoke ChannelState for more info
189 enum HTLCUpdateAwaitingACK {
190         AddHTLC { // TODO: Time out if we're getting close to cltv_expiry
191                 // always outbound
192                 amount_msat: u64,
193                 cltv_expiry: u32,
194                 payment_hash: PaymentHash,
195                 source: HTLCSource,
196                 onion_routing_packet: msgs::OnionPacket,
197         },
198         ClaimHTLC {
199                 payment_preimage: PaymentPreimage,
200                 htlc_id: u64,
201         },
202         FailHTLC {
203                 htlc_id: u64,
204                 err_packet: msgs::OnionErrorPacket,
205         },
206 }
207
208 /// There are a few "states" and then a number of flags which can be applied:
209 /// We first move through init with OurInitSent -> TheirInitSent -> FundingCreated -> FundingSent.
210 /// TheirFundingLocked and OurFundingLocked then get set on FundingSent, and when both are set we
211 /// move on to ChannelFunded.
212 /// Note that PeerDisconnected can be set on both ChannelFunded and FundingSent.
213 /// ChannelFunded can then get all remaining flags set on it, until we finish shutdown, then we
214 /// move on to ShutdownComplete, at which point most calls into this channel are disallowed.
215 enum ChannelState {
216         /// Implies we have (or are prepared to) send our open_channel/accept_channel message
217         OurInitSent = 1 << 0,
218         /// Implies we have received their open_channel/accept_channel message
219         TheirInitSent = 1 << 1,
220         /// We have sent funding_created and are awaiting a funding_signed to advance to FundingSent.
221         /// Note that this is nonsense for an inbound channel as we immediately generate funding_signed
222         /// upon receipt of funding_created, so simply skip this state.
223         FundingCreated = 4,
224         /// Set when we have received/sent funding_created and funding_signed and are thus now waiting
225         /// on the funding transaction to confirm. The FundingLocked flags are set to indicate when we
226         /// and our counterparty consider the funding transaction confirmed.
227         FundingSent = 8,
228         /// Flag which can be set on FundingSent to indicate they sent us a funding_locked message.
229         /// Once both TheirFundingLocked and OurFundingLocked are set, state moves on to ChannelFunded.
230         TheirFundingLocked = 1 << 4,
231         /// Flag which can be set on FundingSent to indicate we sent them a funding_locked message.
232         /// Once both TheirFundingLocked and OurFundingLocked are set, state moves on to ChannelFunded.
233         OurFundingLocked = 1 << 5,
234         ChannelFunded = 64,
235         /// Flag which is set on ChannelFunded and FundingSent indicating remote side is considered
236         /// "disconnected" and no updates are allowed until after we've done a channel_reestablish
237         /// dance.
238         PeerDisconnected = 1 << 7,
239         /// Flag which is set on ChannelFunded, FundingCreated, and FundingSent indicating the user has
240         /// told us they failed to update our ChannelMonitor somewhere and we should pause sending any
241         /// outbound messages until they've managed to do so.
242         MonitorUpdateFailed = 1 << 8,
243         /// Flag which implies that we have sent a commitment_signed but are awaiting the responding
244         /// revoke_and_ack message. During this time period, we can't generate new commitment_signed
245         /// messages as then we will be unable to determine which HTLCs they included in their
246         /// revoke_and_ack implicit ACK, so instead we have to hold them away temporarily to be sent
247         /// later.
248         /// Flag is set on ChannelFunded.
249         AwaitingRemoteRevoke = 1 << 9,
250         /// Flag which is set on ChannelFunded or FundingSent after receiving a shutdown message from
251         /// the remote end. If set, they may not add any new HTLCs to the channel, and we are expected
252         /// to respond with our own shutdown message when possible.
253         RemoteShutdownSent = 1 << 10,
254         /// Flag which is set on ChannelFunded or FundingSent after sending a shutdown message. At this
255         /// point, we may not add any new HTLCs to the channel.
256         LocalShutdownSent = 1 << 11,
257         /// We've successfully negotiated a closing_signed dance. At this point ChannelManager is about
258         /// to drop us, but we store this anyway.
259         ShutdownComplete = 4096,
260 }
261 const BOTH_SIDES_SHUTDOWN_MASK: u32 = ChannelState::LocalShutdownSent as u32 | ChannelState::RemoteShutdownSent as u32;
262 const MULTI_STATE_FLAGS: u32 = BOTH_SIDES_SHUTDOWN_MASK | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32;
263
264 pub const INITIAL_COMMITMENT_NUMBER: u64 = (1 << 48) - 1;
265
266 /// The "channel disabled" bit in channel_update must be set based on whether we are connected to
267 /// our counterparty or not. However, we don't want to announce updates right away to avoid
268 /// spamming the network with updates if the connection is flapping. Instead, we "stage" updates to
269 /// our channel_update message and track the current state here.
270 /// See implementation at [`super::channelmanager::ChannelManager::timer_tick_occurred`].
271 #[derive(Clone, Copy, PartialEq)]
272 pub(super) enum ChannelUpdateStatus {
273         /// We've announced the channel as enabled and are connected to our peer.
274         Enabled,
275         /// Our channel is no longer live, but we haven't announced the channel as disabled yet.
276         DisabledStaged,
277         /// Our channel is live again, but we haven't announced the channel as enabled yet.
278         EnabledStaged,
279         /// We've announced the channel as disabled.
280         Disabled,
281 }
282
283 /// An enum indicating whether the local or remote side offered a given HTLC.
284 enum HTLCInitiator {
285         LocalOffered,
286         RemoteOffered,
287 }
288
289 /// An enum gathering stats on pending HTLCs, either inbound or outbound side.
290 struct HTLCStats {
291         pending_htlcs: u32,
292         pending_htlcs_value_msat: u64,
293         on_counterparty_tx_dust_exposure_msat: u64,
294         on_holder_tx_dust_exposure_msat: u64,
295 }
296
297 /// Used when calculating whether we or the remote can afford an additional HTLC.
298 struct HTLCCandidate {
299         amount_msat: u64,
300         origin: HTLCInitiator,
301 }
302
303 impl HTLCCandidate {
304         fn new(amount_msat: u64, origin: HTLCInitiator) -> Self {
305                 Self {
306                         amount_msat,
307                         origin,
308                 }
309         }
310 }
311
312 /// A return value enum for get_update_fulfill_htlc. See UpdateFulfillCommitFetch variants for
313 /// description
314 enum UpdateFulfillFetch {
315         NewClaim {
316                 monitor_update: ChannelMonitorUpdate,
317                 htlc_value_msat: u64,
318                 msg: Option<msgs::UpdateFulfillHTLC>,
319         },
320         DuplicateClaim {},
321 }
322
323 /// The return type of get_update_fulfill_htlc_and_commit.
324 pub enum UpdateFulfillCommitFetch {
325         /// Indicates the HTLC fulfill is new, and either generated an update_fulfill message, placed
326         /// it in the holding cell, or re-generated the update_fulfill message after the same claim was
327         /// previously placed in the holding cell (and has since been removed).
328         NewClaim {
329                 /// The ChannelMonitorUpdate which places the new payment preimage in the channel monitor
330                 monitor_update: ChannelMonitorUpdate,
331                 /// The value of the HTLC which was claimed, in msat.
332                 htlc_value_msat: u64,
333                 /// The update_fulfill message and commitment_signed message (if the claim was not placed
334                 /// in the holding cell).
335                 msgs: Option<(msgs::UpdateFulfillHTLC, msgs::CommitmentSigned)>,
336         },
337         /// Indicates the HTLC fulfill is duplicative and already existed either in the holding cell
338         /// or has been forgotten (presumably previously claimed).
339         DuplicateClaim {},
340 }
341
342 /// If the majority of the channels funds are to the fundee and the initiator holds only just
343 /// enough funds to cover their reserve value, channels are at risk of getting "stuck". Because the
344 /// initiator controls the feerate, if they then go to increase the channel fee, they may have no
345 /// balance but the fundee is unable to send a payment as the increase in fee more than drains
346 /// their reserve value. Thus, neither side can send a new HTLC and the channel becomes useless.
347 /// Thus, before sending an HTLC when we are the initiator, we check that the feerate can increase
348 /// by this multiple without hitting this case, before sending.
349 /// This multiple is effectively the maximum feerate "jump" we expect until more HTLCs flow over
350 /// the channel. Sadly, there isn't really a good number for this - if we expect to have no new
351 /// HTLCs for days we may need this to suffice for feerate increases across days, but that may
352 /// leave the channel less usable as we hold a bigger reserve.
353 #[cfg(fuzzing)]
354 pub const FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE: u64 = 2;
355 #[cfg(not(fuzzing))]
356 const FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE: u64 = 2;
357
358 // TODO: We should refactor this to be an Inbound/OutboundChannel until initial setup handshaking
359 // has been completed, and then turn into a Channel to get compiler-time enforcement of things like
360 // calling channel_id() before we're set up or things like get_outbound_funding_signed on an
361 // inbound channel.
362 //
363 // Holder designates channel data owned for the benefice of the user client.
364 // Counterparty designates channel data owned by the another channel participant entity.
365 pub(super) struct Channel<Signer: Sign> {
366         #[cfg(any(test, feature = "_test_utils"))]
367         pub(crate) config: ChannelConfig,
368         #[cfg(not(any(test, feature = "_test_utils")))]
369         config: ChannelConfig,
370
371         user_id: u64,
372
373         channel_id: [u8; 32],
374         channel_state: u32,
375         secp_ctx: Secp256k1<secp256k1::All>,
376         channel_value_satoshis: u64,
377
378         latest_monitor_update_id: u64,
379
380         holder_signer: Signer,
381         shutdown_scriptpubkey: Option<ShutdownScript>,
382         destination_script: Script,
383
384         // Our commitment numbers start at 2^48-1 and count down, whereas the ones used in transaction
385         // generation start at 0 and count up...this simplifies some parts of implementation at the
386         // cost of others, but should really just be changed.
387
388         cur_holder_commitment_transaction_number: u64,
389         cur_counterparty_commitment_transaction_number: u64,
390         value_to_self_msat: u64, // Excluding all pending_htlcs, excluding fees
391         pending_inbound_htlcs: Vec<InboundHTLCOutput>,
392         pending_outbound_htlcs: Vec<OutboundHTLCOutput>,
393         holding_cell_htlc_updates: Vec<HTLCUpdateAwaitingACK>,
394
395         /// When resending CS/RAA messages on channel monitor restoration or on reconnect, we always
396         /// need to ensure we resend them in the order we originally generated them. Note that because
397         /// there can only ever be one in-flight CS and/or one in-flight RAA at any time, it is
398         /// sufficient to simply set this to the opposite of any message we are generating as we
399         /// generate it. ie when we generate a CS, we set this to RAAFirst as, if there is a pending
400         /// in-flight RAA to resend, it will have been the first thing we generated, and thus we should
401         /// send it first.
402         resend_order: RAACommitmentOrder,
403
404         monitor_pending_funding_locked: bool,
405         monitor_pending_revoke_and_ack: bool,
406         monitor_pending_commitment_signed: bool,
407         monitor_pending_forwards: Vec<(PendingHTLCInfo, u64)>,
408         monitor_pending_failures: Vec<(HTLCSource, PaymentHash, HTLCFailReason)>,
409
410         // pending_update_fee is filled when sending and receiving update_fee.
411         //
412         // Because it follows the same commitment flow as HTLCs, `FeeUpdateState` is either `Outbound`
413         // or matches a subset of the `InboundHTLCOutput` variants. It is then updated/used when
414         // generating new commitment transactions with exactly the same criteria as inbound/outbound
415         // HTLCs with similar state.
416         pending_update_fee: Option<(u32, FeeUpdateState)>,
417         // If a `send_update_fee()` call is made with ChannelState::AwaitingRemoteRevoke set, we place
418         // it here instead of `pending_update_fee` in the same way as we place outbound HTLC updates in
419         // `holding_cell_htlc_updates` instead of `pending_outbound_htlcs`. It is released into
420         // `pending_update_fee` with the same criteria as outbound HTLC updates but can be updated by
421         // further `send_update_fee` calls, dropping the previous holding cell update entirely.
422         holding_cell_update_fee: Option<u32>,
423         next_holder_htlc_id: u64,
424         next_counterparty_htlc_id: u64,
425         update_time_counter: u32,
426         feerate_per_kw: u32,
427
428         #[cfg(debug_assertions)]
429         /// Max to_local and to_remote outputs in a locally-generated commitment transaction
430         holder_max_commitment_tx_output: Mutex<(u64, u64)>,
431         #[cfg(debug_assertions)]
432         /// Max to_local and to_remote outputs in a remote-generated commitment transaction
433         counterparty_max_commitment_tx_output: Mutex<(u64, u64)>,
434
435         last_sent_closing_fee: Option<(u64, Signature)>, // (fee, holder_sig)
436         target_closing_feerate_sats_per_kw: Option<u32>,
437
438         /// If our counterparty sent us a closing_signed while we were waiting for a `ChannelMonitor`
439         /// update, we need to delay processing it until later. We do that here by simply storing the
440         /// closing_signed message and handling it in `maybe_propose_closing_signed`.
441         pending_counterparty_closing_signed: Option<msgs::ClosingSigned>,
442
443         /// The minimum and maximum absolute fee, in satoshis, we are willing to place on the closing
444         /// transaction. These are set once we reach `closing_negotiation_ready`.
445         #[cfg(test)]
446         pub(crate) closing_fee_limits: Option<(u64, u64)>,
447         #[cfg(not(test))]
448         closing_fee_limits: Option<(u64, u64)>,
449
450         /// The hash of the block in which the funding transaction was included.
451         funding_tx_confirmed_in: Option<BlockHash>,
452         funding_tx_confirmation_height: u32,
453         short_channel_id: Option<u64>,
454
455         counterparty_dust_limit_satoshis: u64,
456         #[cfg(test)]
457         pub(super) holder_dust_limit_satoshis: u64,
458         #[cfg(not(test))]
459         holder_dust_limit_satoshis: u64,
460         #[cfg(test)]
461         pub(super) counterparty_max_htlc_value_in_flight_msat: u64,
462         #[cfg(not(test))]
463         counterparty_max_htlc_value_in_flight_msat: u64,
464         //get_holder_max_htlc_value_in_flight_msat(): u64,
465         /// minimum channel reserve for self to maintain - set by them.
466         counterparty_selected_channel_reserve_satoshis: Option<u64>,
467         // get_holder_selected_channel_reserve_satoshis(channel_value_sats: u64): u64
468         counterparty_htlc_minimum_msat: u64,
469         holder_htlc_minimum_msat: u64,
470         #[cfg(test)]
471         pub counterparty_max_accepted_htlcs: u16,
472         #[cfg(not(test))]
473         counterparty_max_accepted_htlcs: u16,
474         //implied by OUR_MAX_HTLCS: max_accepted_htlcs: u16,
475         minimum_depth: Option<u32>,
476
477         counterparty_forwarding_info: Option<CounterpartyForwardingInfo>,
478
479         pub(crate) channel_transaction_parameters: ChannelTransactionParameters,
480         funding_transaction: Option<Transaction>,
481
482         counterparty_cur_commitment_point: Option<PublicKey>,
483         counterparty_prev_commitment_point: Option<PublicKey>,
484         counterparty_node_id: PublicKey,
485
486         counterparty_shutdown_scriptpubkey: Option<Script>,
487
488         commitment_secrets: CounterpartyCommitmentSecrets,
489
490         channel_update_status: ChannelUpdateStatus,
491         /// Once we reach `closing_negotiation_ready`, we set this, indicating if closing_signed does
492         /// not complete within a single timer tick (one minute), we should force-close the channel.
493         /// This prevents us from keeping unusable channels around forever if our counterparty wishes
494         /// to DoS us.
495         /// Note that this field is reset to false on deserialization to give us a chance to connect to
496         /// our peer and start the closing_signed negotiation fresh.
497         closing_signed_in_flight: bool,
498
499         /// Our counterparty's channel_announcement signatures provided in announcement_signatures.
500         /// This can be used to rebroadcast the channel_announcement message later.
501         announcement_sigs: Option<(Signature, Signature)>,
502
503         // We save these values so we can make sure `next_local_commit_tx_fee_msat` and
504         // `next_remote_commit_tx_fee_msat` properly predict what the next commitment transaction fee will
505         // be, by comparing the cached values to the fee of the tranaction generated by
506         // `build_commitment_transaction`.
507         #[cfg(any(test, feature = "fuzztarget"))]
508         next_local_commitment_tx_fee_info_cached: Mutex<Option<CommitmentTxInfoCached>>,
509         #[cfg(any(test, feature = "fuzztarget"))]
510         next_remote_commitment_tx_fee_info_cached: Mutex<Option<CommitmentTxInfoCached>>,
511
512         /// lnd has a long-standing bug where, upon reconnection, if the channel is not yet confirmed
513         /// they will not send a channel_reestablish until the channel locks in. Then, they will send a
514         /// funding_locked *before* sending the channel_reestablish (which is clearly a violation of
515         /// the BOLT specs). We copy c-lightning's workaround here and simply store the funding_locked
516         /// message until we receive a channel_reestablish.
517         ///
518         /// See-also <https://github.com/lightningnetwork/lnd/issues/4006>
519         pub workaround_lnd_bug_4006: Option<msgs::FundingLocked>,
520
521         #[cfg(any(test, feature = "fuzztarget"))]
522         // When we receive an HTLC fulfill on an outbound path, we may immediately fulfill the
523         // corresponding HTLC on the inbound path. If, then, the outbound path channel is
524         // disconnected and reconnected (before we've exchange commitment_signed and revoke_and_ack
525         // messages), they may re-broadcast their update_fulfill_htlc, causing a duplicate claim. This
526         // is fine, but as a sanity check in our failure to generate the second claim, we check here
527         // that the original was a claim, and that we aren't now trying to fulfill a failed HTLC.
528         historical_inbound_htlc_fulfills: HashSet<u64>,
529 }
530
531 #[cfg(any(test, feature = "fuzztarget"))]
532 struct CommitmentTxInfoCached {
533         fee: u64,
534         total_pending_htlcs: usize,
535         next_holder_htlc_id: u64,
536         next_counterparty_htlc_id: u64,
537         feerate: u32,
538 }
539
540 pub const OUR_MAX_HTLCS: u16 = 50; //TODO
541
542 #[cfg(not(test))]
543 const COMMITMENT_TX_BASE_WEIGHT: u64 = 724;
544 #[cfg(test)]
545 pub const COMMITMENT_TX_BASE_WEIGHT: u64 = 724;
546 #[cfg(not(test))]
547 const COMMITMENT_TX_WEIGHT_PER_HTLC: u64 = 172;
548 #[cfg(test)]
549 pub const COMMITMENT_TX_WEIGHT_PER_HTLC: u64 = 172;
550
551 pub const ANCHOR_OUTPUT_VALUE_SATOSHI: u64 = 330;
552
553 /// Maximum `funding_satoshis` value, according to the BOLT #2 specification
554 /// it's 2^24.
555 pub const MAX_FUNDING_SATOSHIS: u64 = 1 << 24;
556
557 /// The maximum network dust limit for standard script formats. This currently represents the
558 /// minimum output value for a P2SH output before Bitcoin Core 22 considers the entire
559 /// transaction non-standard and thus refuses to relay it.
560 /// We also use this as the maximum counterparty `dust_limit_satoshis` allowed, given many
561 /// implementations use this value for their dust limit today.
562 pub const MAX_STD_OUTPUT_DUST_LIMIT_SATOSHIS: u64 = 546;
563
564 /// The maximum channel dust limit we will accept from our counterparty.
565 pub const MAX_CHAN_DUST_LIMIT_SATOSHIS: u64 = MAX_STD_OUTPUT_DUST_LIMIT_SATOSHIS;
566
567 /// The dust limit is used for both the commitment transaction outputs as well as the closing
568 /// transactions. For cooperative closing transactions, we require segwit outputs, though accept
569 /// *any* segwit scripts, which are allowed to be up to 42 bytes in length.
570 /// In order to avoid having to concern ourselves with standardness during the closing process, we
571 /// simply require our counterparty to use a dust limit which will leave any segwit output
572 /// standard.
573 /// See https://github.com/lightningnetwork/lightning-rfc/issues/905 for more details.
574 pub const MIN_CHAN_DUST_LIMIT_SATOSHIS: u64 = 354;
575
576 /// Used to return a simple Error back to ChannelManager. Will get converted to a
577 /// msgs::ErrorAction::SendErrorMessage or msgs::ErrorAction::IgnoreError as appropriate with our
578 /// channel_id in ChannelManager.
579 pub(super) enum ChannelError {
580         Ignore(String),
581         Warn(String),
582         Close(String),
583         CloseDelayBroadcast(String),
584 }
585
586 impl fmt::Debug for ChannelError {
587         fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
588                 match self {
589                         &ChannelError::Ignore(ref e) => write!(f, "Ignore : {}", e),
590                         &ChannelError::Warn(ref e) => write!(f, "Warn : {}", e),
591                         &ChannelError::Close(ref e) => write!(f, "Close : {}", e),
592                         &ChannelError::CloseDelayBroadcast(ref e) => write!(f, "CloseDelayBroadcast : {}", e)
593                 }
594         }
595 }
596
597 macro_rules! secp_check {
598         ($res: expr, $err: expr) => {
599                 match $res {
600                         Ok(thing) => thing,
601                         Err(_) => return Err(ChannelError::Close($err)),
602                 }
603         };
604 }
605
606 impl<Signer: Sign> Channel<Signer> {
607         // Convert constants + channel value to limits:
608         fn get_holder_max_htlc_value_in_flight_msat(channel_value_satoshis: u64) -> u64 {
609                 channel_value_satoshis * 1000 / 10 //TODO
610         }
611
612         /// Returns a minimum channel reserve value the remote needs to maintain,
613         /// required by us.
614         ///
615         /// Guaranteed to return a value no larger than channel_value_satoshis
616         pub(crate) fn get_holder_selected_channel_reserve_satoshis(channel_value_satoshis: u64) -> u64 {
617                 let (q, _) = channel_value_satoshis.overflowing_div(100);
618                 cmp::min(channel_value_satoshis, cmp::max(q, 1000)) //TODO
619         }
620
621         // Constructors:
622         pub fn new_outbound<K: Deref, F: Deref>(fee_estimator: &F, keys_provider: &K, counterparty_node_id: PublicKey, their_features: &InitFeatures, channel_value_satoshis: u64, push_msat: u64, user_id: u64, config: &UserConfig) -> Result<Channel<Signer>, APIError>
623         where K::Target: KeysInterface<Signer = Signer>,
624               F::Target: FeeEstimator,
625         {
626                 let holder_selected_contest_delay = config.own_channel_config.our_to_self_delay;
627                 let holder_signer = keys_provider.get_channel_signer(false, channel_value_satoshis);
628                 let pubkeys = holder_signer.pubkeys().clone();
629
630                 if channel_value_satoshis >= MAX_FUNDING_SATOSHIS {
631                         return Err(APIError::APIMisuseError{err: format!("funding_value must be smaller than {}, it was {}", MAX_FUNDING_SATOSHIS, channel_value_satoshis)});
632                 }
633                 let channel_value_msat = channel_value_satoshis * 1000;
634                 if push_msat > channel_value_msat {
635                         return Err(APIError::APIMisuseError { err: format!("Push value ({}) was larger than channel_value ({})", push_msat, channel_value_msat) });
636                 }
637                 if holder_selected_contest_delay < BREAKDOWN_TIMEOUT {
638                         return Err(APIError::APIMisuseError {err: format!("Configured with an unreasonable our_to_self_delay ({}) putting user funds at risks", holder_selected_contest_delay)});
639                 }
640                 let holder_selected_channel_reserve_satoshis = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(channel_value_satoshis);
641                 if holder_selected_channel_reserve_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
642                         return Err(APIError::APIMisuseError { err: format!("Holder selected channel  reserve below implemention limit dust_limit_satoshis {}", holder_selected_channel_reserve_satoshis) });
643                 }
644
645                 let feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
646
647                 let mut secp_ctx = Secp256k1::new();
648                 secp_ctx.seeded_randomize(&keys_provider.get_secure_random_bytes());
649
650                 let shutdown_scriptpubkey = if config.channel_options.commit_upfront_shutdown_pubkey {
651                         Some(keys_provider.get_shutdown_scriptpubkey())
652                 } else { None };
653
654                 if let Some(shutdown_scriptpubkey) = &shutdown_scriptpubkey {
655                         if !shutdown_scriptpubkey.is_compatible(&their_features) {
656                                 return Err(APIError::IncompatibleShutdownScript { script: shutdown_scriptpubkey.clone() });
657                         }
658                 }
659
660                 Ok(Channel {
661                         user_id,
662                         config: config.channel_options.clone(),
663
664                         channel_id: keys_provider.get_secure_random_bytes(),
665                         channel_state: ChannelState::OurInitSent as u32,
666                         secp_ctx,
667                         channel_value_satoshis,
668
669                         latest_monitor_update_id: 0,
670
671                         holder_signer,
672                         shutdown_scriptpubkey,
673                         destination_script: keys_provider.get_destination_script(),
674
675                         cur_holder_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
676                         cur_counterparty_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
677                         value_to_self_msat: channel_value_satoshis * 1000 - push_msat,
678
679                         pending_inbound_htlcs: Vec::new(),
680                         pending_outbound_htlcs: Vec::new(),
681                         holding_cell_htlc_updates: Vec::new(),
682                         pending_update_fee: None,
683                         holding_cell_update_fee: None,
684                         next_holder_htlc_id: 0,
685                         next_counterparty_htlc_id: 0,
686                         update_time_counter: 1,
687
688                         resend_order: RAACommitmentOrder::CommitmentFirst,
689
690                         monitor_pending_funding_locked: false,
691                         monitor_pending_revoke_and_ack: false,
692                         monitor_pending_commitment_signed: false,
693                         monitor_pending_forwards: Vec::new(),
694                         monitor_pending_failures: Vec::new(),
695
696                         #[cfg(debug_assertions)]
697                         holder_max_commitment_tx_output: Mutex::new((channel_value_satoshis * 1000 - push_msat, push_msat)),
698                         #[cfg(debug_assertions)]
699                         counterparty_max_commitment_tx_output: Mutex::new((channel_value_satoshis * 1000 - push_msat, push_msat)),
700
701                         last_sent_closing_fee: None,
702                         pending_counterparty_closing_signed: None,
703                         closing_fee_limits: None,
704                         target_closing_feerate_sats_per_kw: None,
705
706                         funding_tx_confirmed_in: None,
707                         funding_tx_confirmation_height: 0,
708                         short_channel_id: None,
709
710                         feerate_per_kw: feerate,
711                         counterparty_dust_limit_satoshis: 0,
712                         holder_dust_limit_satoshis: MIN_CHAN_DUST_LIMIT_SATOSHIS,
713                         counterparty_max_htlc_value_in_flight_msat: 0,
714                         counterparty_selected_channel_reserve_satoshis: None, // Filled in in accept_channel
715                         counterparty_htlc_minimum_msat: 0,
716                         holder_htlc_minimum_msat: if config.own_channel_config.our_htlc_minimum_msat == 0 { 1 } else { config.own_channel_config.our_htlc_minimum_msat },
717                         counterparty_max_accepted_htlcs: 0,
718                         minimum_depth: None, // Filled in in accept_channel
719
720                         counterparty_forwarding_info: None,
721
722                         channel_transaction_parameters: ChannelTransactionParameters {
723                                 holder_pubkeys: pubkeys,
724                                 holder_selected_contest_delay: config.own_channel_config.our_to_self_delay,
725                                 is_outbound_from_holder: true,
726                                 counterparty_parameters: None,
727                                 funding_outpoint: None
728                         },
729                         funding_transaction: None,
730
731                         counterparty_cur_commitment_point: None,
732                         counterparty_prev_commitment_point: None,
733                         counterparty_node_id,
734
735                         counterparty_shutdown_scriptpubkey: None,
736
737                         commitment_secrets: CounterpartyCommitmentSecrets::new(),
738
739                         channel_update_status: ChannelUpdateStatus::Enabled,
740                         closing_signed_in_flight: false,
741
742                         announcement_sigs: None,
743
744                         #[cfg(any(test, feature = "fuzztarget"))]
745                         next_local_commitment_tx_fee_info_cached: Mutex::new(None),
746                         #[cfg(any(test, feature = "fuzztarget"))]
747                         next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
748
749                         workaround_lnd_bug_4006: None,
750
751                         #[cfg(any(test, feature = "fuzztarget"))]
752                         historical_inbound_htlc_fulfills: HashSet::new(),
753                 })
754         }
755
756         fn check_remote_fee<F: Deref>(fee_estimator: &F, feerate_per_kw: u32) -> Result<(), ChannelError>
757                 where F::Target: FeeEstimator
758         {
759                 let lower_limit = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
760                 if feerate_per_kw < lower_limit {
761                         return Err(ChannelError::Close(format!("Peer's feerate much too low. Actual: {}. Our expected lower limit: {}", feerate_per_kw, lower_limit)));
762                 }
763                 // We only bound the fee updates on the upper side to prevent completely absurd feerates,
764                 // always accepting up to 25 sat/vByte or 10x our fee estimator's "High Priority" fee.
765                 // We generally don't care too much if they set the feerate to something very high, but it
766                 // could result in the channel being useless due to everything being dust.
767                 let upper_limit = cmp::max(250 * 25,
768                         fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::HighPriority) as u64 * 10);
769                 if feerate_per_kw as u64 > upper_limit {
770                         return Err(ChannelError::Close(format!("Peer's feerate much too high. Actual: {}. Our expected upper limit: {}", feerate_per_kw, upper_limit)));
771                 }
772                 Ok(())
773         }
774
775         /// Creates a new channel from a remote sides' request for one.
776         /// Assumes chain_hash has already been checked and corresponds with what we expect!
777         pub fn new_from_req<K: Deref, F: Deref>(fee_estimator: &F, keys_provider: &K, counterparty_node_id: PublicKey, their_features: &InitFeatures, msg: &msgs::OpenChannel, user_id: u64, config: &UserConfig) -> Result<Channel<Signer>, ChannelError>
778                 where K::Target: KeysInterface<Signer = Signer>,
779           F::Target: FeeEstimator
780         {
781                 let holder_signer = keys_provider.get_channel_signer(true, msg.funding_satoshis);
782                 let pubkeys = holder_signer.pubkeys().clone();
783                 let counterparty_pubkeys = ChannelPublicKeys {
784                         funding_pubkey: msg.funding_pubkey,
785                         revocation_basepoint: msg.revocation_basepoint,
786                         payment_point: msg.payment_point,
787                         delayed_payment_basepoint: msg.delayed_payment_basepoint,
788                         htlc_basepoint: msg.htlc_basepoint
789                 };
790                 let mut local_config = (*config).channel_options.clone();
791
792                 if config.own_channel_config.our_to_self_delay < BREAKDOWN_TIMEOUT {
793                         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)));
794                 }
795
796                 // Check sanity of message fields:
797                 if msg.funding_satoshis >= MAX_FUNDING_SATOSHIS {
798                         return Err(ChannelError::Close(format!("Funding must be smaller than {}. It was {}", MAX_FUNDING_SATOSHIS, msg.funding_satoshis)));
799                 }
800                 if msg.channel_reserve_satoshis > msg.funding_satoshis {
801                         return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must be not greater than funding_satoshis: {}", msg.channel_reserve_satoshis, msg.funding_satoshis)));
802                 }
803                 let funding_value = (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000;
804                 if msg.push_msat > funding_value {
805                         return Err(ChannelError::Close(format!("push_msat {} was larger than funding value {}", msg.push_msat, funding_value)));
806                 }
807                 if msg.dust_limit_satoshis > msg.funding_satoshis {
808                         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)));
809                 }
810                 if msg.dust_limit_satoshis > msg.channel_reserve_satoshis {
811                         return Err(ChannelError::Close(format!("Bogus; channel reserve ({}) is less than dust limit ({})", msg.channel_reserve_satoshis, msg.dust_limit_satoshis)));
812                 }
813                 let full_channel_value_msat = (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000;
814                 if msg.htlc_minimum_msat >= full_channel_value_msat {
815                         return Err(ChannelError::Close(format!("Minimum htlc value ({}) was larger than full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat)));
816                 }
817                 Channel::<Signer>::check_remote_fee(fee_estimator, msg.feerate_per_kw)?;
818
819                 let max_counterparty_selected_contest_delay = u16::min(config.peer_channel_config_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
820                 if msg.to_self_delay > max_counterparty_selected_contest_delay {
821                         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)));
822                 }
823                 if msg.max_accepted_htlcs < 1 {
824                         return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel".to_owned()));
825                 }
826                 if msg.max_accepted_htlcs > MAX_HTLCS {
827                         return Err(ChannelError::Close(format!("max_accepted_htlcs was {}. It must not be larger than {}", msg.max_accepted_htlcs, MAX_HTLCS)));
828                 }
829
830                 // Now check against optional parameters as set by config...
831                 if msg.funding_satoshis < config.peer_channel_config_limits.min_funding_satoshis {
832                         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)));
833                 }
834                 if msg.htlc_minimum_msat > config.peer_channel_config_limits.max_htlc_minimum_msat {
835                         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)));
836                 }
837                 if msg.max_htlc_value_in_flight_msat < config.peer_channel_config_limits.min_max_htlc_value_in_flight_msat {
838                         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)));
839                 }
840                 if msg.channel_reserve_satoshis > config.peer_channel_config_limits.max_channel_reserve_satoshis {
841                         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)));
842                 }
843                 if msg.max_accepted_htlcs < config.peer_channel_config_limits.min_max_accepted_htlcs {
844                         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)));
845                 }
846                 if msg.dust_limit_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
847                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the implementation limit ({})", msg.dust_limit_satoshis, MIN_CHAN_DUST_LIMIT_SATOSHIS)));
848                 }
849                 if msg.dust_limit_satoshis >  MAX_CHAN_DUST_LIMIT_SATOSHIS {
850                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the implementation limit ({})", msg.dust_limit_satoshis, MAX_CHAN_DUST_LIMIT_SATOSHIS)));
851                 }
852
853                 // Convert things into internal flags and prep our state:
854
855                 let announce = if (msg.channel_flags & 1) == 1 { true } else { false };
856                 if config.peer_channel_config_limits.force_announced_channel_preference {
857                         if local_config.announced_channel != announce {
858                                 return Err(ChannelError::Close("Peer tried to open channel but their announcement preference is different from ours".to_owned()));
859                         }
860                 }
861                 // we either accept their preference or the preferences match
862                 local_config.announced_channel = announce;
863
864                 let background_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
865
866                 let holder_selected_channel_reserve_satoshis = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(msg.funding_satoshis);
867                 if holder_selected_channel_reserve_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
868                         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)));
869                 }
870                 if msg.channel_reserve_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
871                         return Err(ChannelError::Close(format!("channel_reserve_satoshis ({}) is smaller than our dust limit ({})", msg.channel_reserve_satoshis, MIN_CHAN_DUST_LIMIT_SATOSHIS)));
872                 }
873                 if holder_selected_channel_reserve_satoshis < msg.dust_limit_satoshis {
874                         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)));
875                 }
876
877                 // check if the funder's amount for the initial commitment tx is sufficient
878                 // for full fee payment
879                 let funders_amount_msat = msg.funding_satoshis * 1000 - msg.push_msat;
880                 let lower_limit = background_feerate as u64 * COMMITMENT_TX_BASE_WEIGHT;
881                 if funders_amount_msat < lower_limit {
882                         return Err(ChannelError::Close(format!("Insufficient funding amount ({}) for initial commitment. Must be at least {}", funders_amount_msat, lower_limit)));
883                 }
884
885                 let to_local_msat = msg.push_msat;
886                 let to_remote_msat = funders_amount_msat - background_feerate as u64 * COMMITMENT_TX_BASE_WEIGHT;
887                 if to_local_msat <= msg.channel_reserve_satoshis * 1000 && to_remote_msat <= holder_selected_channel_reserve_satoshis * 1000 {
888                         return Err(ChannelError::Close("Insufficient funding amount for initial commitment".to_owned()));
889                 }
890
891                 let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() {
892                         match &msg.shutdown_scriptpubkey {
893                                 &OptionalField::Present(ref script) => {
894                                         // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything
895                                         if script.len() == 0 {
896                                                 None
897                                         } else {
898                                                 if !script::is_bolt2_compliant(&script, their_features) {
899                                                         return Err(ChannelError::Close(format!("Peer is signaling upfront_shutdown but has provided an unacceptable scriptpubkey format: {}", script)))
900                                                 }
901                                                 Some(script.clone())
902                                         }
903                                 },
904                                 // 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
905                                 &OptionalField::Absent => {
906                                         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()));
907                                 }
908                         }
909                 } else { None };
910
911                 let shutdown_scriptpubkey = if config.channel_options.commit_upfront_shutdown_pubkey {
912                         Some(keys_provider.get_shutdown_scriptpubkey())
913                 } else { None };
914
915                 if let Some(shutdown_scriptpubkey) = &shutdown_scriptpubkey {
916                         if !shutdown_scriptpubkey.is_compatible(&their_features) {
917                                 return Err(ChannelError::Close(format!("Provided a scriptpubkey format not accepted by peer: {}", shutdown_scriptpubkey)));
918                         }
919                 }
920
921                 let mut secp_ctx = Secp256k1::new();
922                 secp_ctx.seeded_randomize(&keys_provider.get_secure_random_bytes());
923
924                 let chan = Channel {
925                         user_id,
926                         config: local_config,
927
928                         channel_id: msg.temporary_channel_id,
929                         channel_state: (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32),
930                         secp_ctx,
931
932                         latest_monitor_update_id: 0,
933
934                         holder_signer,
935                         shutdown_scriptpubkey,
936                         destination_script: keys_provider.get_destination_script(),
937
938                         cur_holder_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
939                         cur_counterparty_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
940                         value_to_self_msat: msg.push_msat,
941
942                         pending_inbound_htlcs: Vec::new(),
943                         pending_outbound_htlcs: Vec::new(),
944                         holding_cell_htlc_updates: Vec::new(),
945                         pending_update_fee: None,
946                         holding_cell_update_fee: None,
947                         next_holder_htlc_id: 0,
948                         next_counterparty_htlc_id: 0,
949                         update_time_counter: 1,
950
951                         resend_order: RAACommitmentOrder::CommitmentFirst,
952
953                         monitor_pending_funding_locked: false,
954                         monitor_pending_revoke_and_ack: false,
955                         monitor_pending_commitment_signed: false,
956                         monitor_pending_forwards: Vec::new(),
957                         monitor_pending_failures: Vec::new(),
958
959                         #[cfg(debug_assertions)]
960                         holder_max_commitment_tx_output: Mutex::new((msg.push_msat, msg.funding_satoshis * 1000 - msg.push_msat)),
961                         #[cfg(debug_assertions)]
962                         counterparty_max_commitment_tx_output: Mutex::new((msg.push_msat, msg.funding_satoshis * 1000 - msg.push_msat)),
963
964                         last_sent_closing_fee: None,
965                         pending_counterparty_closing_signed: None,
966                         closing_fee_limits: None,
967                         target_closing_feerate_sats_per_kw: None,
968
969                         funding_tx_confirmed_in: None,
970                         funding_tx_confirmation_height: 0,
971                         short_channel_id: None,
972
973                         feerate_per_kw: msg.feerate_per_kw,
974                         channel_value_satoshis: msg.funding_satoshis,
975                         counterparty_dust_limit_satoshis: msg.dust_limit_satoshis,
976                         holder_dust_limit_satoshis: MIN_CHAN_DUST_LIMIT_SATOSHIS,
977                         counterparty_max_htlc_value_in_flight_msat: cmp::min(msg.max_htlc_value_in_flight_msat, msg.funding_satoshis * 1000),
978                         counterparty_selected_channel_reserve_satoshis: Some(msg.channel_reserve_satoshis),
979                         counterparty_htlc_minimum_msat: msg.htlc_minimum_msat,
980                         holder_htlc_minimum_msat: if config.own_channel_config.our_htlc_minimum_msat == 0 { 1 } else { config.own_channel_config.our_htlc_minimum_msat },
981                         counterparty_max_accepted_htlcs: msg.max_accepted_htlcs,
982                         minimum_depth: Some(config.own_channel_config.minimum_depth),
983
984                         counterparty_forwarding_info: None,
985
986                         channel_transaction_parameters: ChannelTransactionParameters {
987                                 holder_pubkeys: pubkeys,
988                                 holder_selected_contest_delay: config.own_channel_config.our_to_self_delay,
989                                 is_outbound_from_holder: false,
990                                 counterparty_parameters: Some(CounterpartyChannelTransactionParameters {
991                                         selected_contest_delay: msg.to_self_delay,
992                                         pubkeys: counterparty_pubkeys,
993                                 }),
994                                 funding_outpoint: None
995                         },
996                         funding_transaction: None,
997
998                         counterparty_cur_commitment_point: Some(msg.first_per_commitment_point),
999                         counterparty_prev_commitment_point: None,
1000                         counterparty_node_id,
1001
1002                         counterparty_shutdown_scriptpubkey,
1003
1004                         commitment_secrets: CounterpartyCommitmentSecrets::new(),
1005
1006                         channel_update_status: ChannelUpdateStatus::Enabled,
1007                         closing_signed_in_flight: false,
1008
1009                         announcement_sigs: None,
1010
1011                         #[cfg(any(test, feature = "fuzztarget"))]
1012                         next_local_commitment_tx_fee_info_cached: Mutex::new(None),
1013                         #[cfg(any(test, feature = "fuzztarget"))]
1014                         next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
1015
1016                         workaround_lnd_bug_4006: None,
1017
1018                         #[cfg(any(test, feature = "fuzztarget"))]
1019                         historical_inbound_htlc_fulfills: HashSet::new(),
1020                 };
1021
1022                 Ok(chan)
1023         }
1024
1025         /// Transaction nomenclature is somewhat confusing here as there are many different cases - a
1026         /// transaction is referred to as "a's transaction" implying that a will be able to broadcast
1027         /// the transaction. Thus, b will generally be sending a signature over such a transaction to
1028         /// a, and a can revoke the transaction by providing b the relevant per_commitment_secret. As
1029         /// such, a transaction is generally the result of b increasing the amount paid to a (or adding
1030         /// an HTLC to a).
1031         /// @local is used only to convert relevant internal structures which refer to remote vs local
1032         /// to decide value of outputs and direction of HTLCs.
1033         /// @generated_by_local is used to determine *which* HTLCs to include - noting that the HTLC
1034         /// state may indicate that one peer has informed the other that they'd like to add an HTLC but
1035         /// have not yet committed it. Such HTLCs will only be included in transactions which are being
1036         /// generated by the peer which proposed adding the HTLCs, and thus we need to understand both
1037         /// which peer generated this transaction and "to whom" this transaction flows.
1038         /// Returns (the transaction info, the number of HTLC outputs which were present in the
1039         /// transaction, the list of HTLCs which were not ignored when building the transaction).
1040         /// Note that below-dust HTLCs are included in the fourth return value, but not the third, and
1041         /// sources are provided only for outbound HTLCs in the fourth return value.
1042         #[inline]
1043         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 {
1044                 let mut included_dust_htlcs: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::new();
1045                 let num_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len();
1046                 let mut included_non_dust_htlcs: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::with_capacity(num_htlcs);
1047
1048                 let broadcaster_dust_limit_satoshis = if local { self.holder_dust_limit_satoshis } else { self.counterparty_dust_limit_satoshis };
1049                 let mut remote_htlc_total_msat = 0;
1050                 let mut local_htlc_total_msat = 0;
1051                 let mut value_to_self_msat_offset = 0;
1052
1053                 let mut feerate_per_kw = self.feerate_per_kw;
1054                 if let Some((feerate, update_state)) = self.pending_update_fee {
1055                         if match update_state {
1056                                 // Note that these match the inclusion criteria when scanning
1057                                 // pending_inbound_htlcs below.
1058                                 FeeUpdateState::RemoteAnnounced => { debug_assert!(!self.is_outbound()); !generated_by_local },
1059                                 FeeUpdateState::AwaitingRemoteRevokeToAnnounce => { debug_assert!(!self.is_outbound()); !generated_by_local },
1060                                 FeeUpdateState::Outbound => { assert!(self.is_outbound());  generated_by_local },
1061                         } {
1062                                 feerate_per_kw = feerate;
1063                         }
1064                 }
1065
1066                 log_trace!(logger, "Building commitment transaction number {} (really {} xor {}) for channel {} for {}, generated by {} with fee {}...",
1067                         commitment_number, (INITIAL_COMMITMENT_NUMBER - commitment_number),
1068                         get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound()),
1069                         log_bytes!(self.channel_id), if local { "us" } else { "remote" }, if generated_by_local { "us" } else { "remote" }, feerate_per_kw);
1070
1071                 macro_rules! get_htlc_in_commitment {
1072                         ($htlc: expr, $offered: expr) => {
1073                                 HTLCOutputInCommitment {
1074                                         offered: $offered,
1075                                         amount_msat: $htlc.amount_msat,
1076                                         cltv_expiry: $htlc.cltv_expiry,
1077                                         payment_hash: $htlc.payment_hash,
1078                                         transaction_output_index: None
1079                                 }
1080                         }
1081                 }
1082
1083                 macro_rules! add_htlc_output {
1084                         ($htlc: expr, $outbound: expr, $source: expr, $state_name: expr) => {
1085                                 if $outbound == local { // "offered HTLC output"
1086                                         let htlc_in_tx = get_htlc_in_commitment!($htlc, true);
1087                                         if $htlc.amount_msat / 1000 >= broadcaster_dust_limit_satoshis + (feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) {
1088                                                 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);
1089                                                 included_non_dust_htlcs.push((htlc_in_tx, $source));
1090                                         } else {
1091                                                 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);
1092                                                 included_dust_htlcs.push((htlc_in_tx, $source));
1093                                         }
1094                                 } else {
1095                                         let htlc_in_tx = get_htlc_in_commitment!($htlc, false);
1096                                         if $htlc.amount_msat / 1000 >= broadcaster_dust_limit_satoshis + (feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) {
1097                                                 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);
1098                                                 included_non_dust_htlcs.push((htlc_in_tx, $source));
1099                                         } else {
1100                                                 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);
1101                                                 included_dust_htlcs.push((htlc_in_tx, $source));
1102                                         }
1103                                 }
1104                         }
1105                 }
1106
1107                 for ref htlc in self.pending_inbound_htlcs.iter() {
1108                         let (include, state_name) = match htlc.state {
1109                                 InboundHTLCState::RemoteAnnounced(_) => (!generated_by_local, "RemoteAnnounced"),
1110                                 InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_) => (!generated_by_local, "AwaitingRemoteRevokeToAnnounce"),
1111                                 InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) => (true, "AwaitingAnnouncedRemoteRevoke"),
1112                                 InboundHTLCState::Committed => (true, "Committed"),
1113                                 InboundHTLCState::LocalRemoved(_) => (!generated_by_local, "LocalRemoved"),
1114                         };
1115
1116                         if include {
1117                                 add_htlc_output!(htlc, false, None, state_name);
1118                                 remote_htlc_total_msat += htlc.amount_msat;
1119                         } else {
1120                                 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);
1121                                 match &htlc.state {
1122                                         &InboundHTLCState::LocalRemoved(ref reason) => {
1123                                                 if generated_by_local {
1124                                                         if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
1125                                                                 value_to_self_msat_offset += htlc.amount_msat as i64;
1126                                                         }
1127                                                 }
1128                                         },
1129                                         _ => {},
1130                                 }
1131                         }
1132                 }
1133
1134                 for ref htlc in self.pending_outbound_htlcs.iter() {
1135                         let (include, state_name) = match htlc.state {
1136                                 OutboundHTLCState::LocalAnnounced(_) => (generated_by_local, "LocalAnnounced"),
1137                                 OutboundHTLCState::Committed => (true, "Committed"),
1138                                 OutboundHTLCState::RemoteRemoved(_) => (generated_by_local, "RemoteRemoved"),
1139                                 OutboundHTLCState::AwaitingRemoteRevokeToRemove(_) => (generated_by_local, "AwaitingRemoteRevokeToRemove"),
1140                                 OutboundHTLCState::AwaitingRemovedRemoteRevoke(_) => (false, "AwaitingRemovedRemoteRevoke"),
1141                         };
1142
1143                         if include {
1144                                 add_htlc_output!(htlc, true, Some(&htlc.source), state_name);
1145                                 local_htlc_total_msat += htlc.amount_msat;
1146                         } else {
1147                                 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);
1148                                 match htlc.state {
1149                                         OutboundHTLCState::AwaitingRemoteRevokeToRemove(None)|OutboundHTLCState::AwaitingRemovedRemoteRevoke(None) => {
1150                                                 value_to_self_msat_offset -= htlc.amount_msat as i64;
1151                                         },
1152                                         OutboundHTLCState::RemoteRemoved(None) => {
1153                                                 if !generated_by_local {
1154                                                         value_to_self_msat_offset -= htlc.amount_msat as i64;
1155                                                 }
1156                                         },
1157                                         _ => {},
1158                                 }
1159                         }
1160                 }
1161
1162                 let value_to_self_msat: i64 = (self.value_to_self_msat - local_htlc_total_msat) as i64 + value_to_self_msat_offset;
1163                 assert!(value_to_self_msat >= 0);
1164                 // Note that in case they have several just-awaiting-last-RAA fulfills in-progress (ie
1165                 // AwaitingRemoteRevokeToRemove or AwaitingRemovedRemoteRevoke) we may have allowed them to
1166                 // "violate" their reserve value by couting those against it. Thus, we have to convert
1167                 // everything to i64 before subtracting as otherwise we can overflow.
1168                 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;
1169                 assert!(value_to_remote_msat >= 0);
1170
1171                 #[cfg(debug_assertions)]
1172                 {
1173                         // Make sure that the to_self/to_remote is always either past the appropriate
1174                         // channel_reserve *or* it is making progress towards it.
1175                         let mut broadcaster_max_commitment_tx_output = if generated_by_local {
1176                                 self.holder_max_commitment_tx_output.lock().unwrap()
1177                         } else {
1178                                 self.counterparty_max_commitment_tx_output.lock().unwrap()
1179                         };
1180                         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);
1181                         broadcaster_max_commitment_tx_output.0 = cmp::max(broadcaster_max_commitment_tx_output.0, value_to_self_msat as u64);
1182                         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);
1183                         broadcaster_max_commitment_tx_output.1 = cmp::max(broadcaster_max_commitment_tx_output.1, value_to_remote_msat as u64);
1184                 }
1185
1186                 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;
1187                 let (value_to_self, value_to_remote) = if self.is_outbound() {
1188                         (value_to_self_msat / 1000 - total_fee as i64, value_to_remote_msat / 1000)
1189                 } else {
1190                         (value_to_self_msat / 1000, value_to_remote_msat / 1000 - total_fee as i64)
1191                 };
1192
1193                 let mut value_to_a = if local { value_to_self } else { value_to_remote };
1194                 let mut value_to_b = if local { value_to_remote } else { value_to_self };
1195                 let (funding_pubkey_a, funding_pubkey_b) = if local {
1196                         (self.get_holder_pubkeys().funding_pubkey, self.get_counterparty_pubkeys().funding_pubkey)
1197                 } else {
1198                         (self.get_counterparty_pubkeys().funding_pubkey, self.get_holder_pubkeys().funding_pubkey)
1199                 };
1200
1201                 if value_to_a >= (broadcaster_dust_limit_satoshis as i64) {
1202                         log_trace!(logger, "   ...including {} output with value {}", if local { "to_local" } else { "to_remote" }, value_to_a);
1203                 } else {
1204                         value_to_a = 0;
1205                 }
1206
1207                 if value_to_b >= (broadcaster_dust_limit_satoshis as i64) {
1208                         log_trace!(logger, "   ...including {} output with value {}", if local { "to_remote" } else { "to_local" }, value_to_b);
1209                 } else {
1210                         value_to_b = 0;
1211                 }
1212
1213                 let num_nondust_htlcs = included_non_dust_htlcs.len();
1214
1215                 let channel_parameters =
1216                         if local { self.channel_transaction_parameters.as_holder_broadcastable() }
1217                         else { self.channel_transaction_parameters.as_counterparty_broadcastable() };
1218                 let tx = CommitmentTransaction::new_with_auxiliary_htlc_data(commitment_number,
1219                                                                              value_to_a as u64,
1220                                                                              value_to_b as u64,
1221                                                                              false,
1222                                                                              funding_pubkey_a,
1223                                                                              funding_pubkey_b,
1224                                                                              keys.clone(),
1225                                                                              feerate_per_kw,
1226                                                                              &mut included_non_dust_htlcs,
1227                                                                              &channel_parameters
1228                 );
1229                 let mut htlcs_included = included_non_dust_htlcs;
1230                 // The unwrap is safe, because all non-dust HTLCs have been assigned an output index
1231                 htlcs_included.sort_unstable_by_key(|h| h.0.transaction_output_index.unwrap());
1232                 htlcs_included.append(&mut included_dust_htlcs);
1233
1234                 (tx, feerate_per_kw, num_nondust_htlcs, htlcs_included)
1235         }
1236
1237         #[inline]
1238         fn get_closing_scriptpubkey(&self) -> Script {
1239                 // The shutdown scriptpubkey is set on channel opening when option_upfront_shutdown_script
1240                 // is signaled. Otherwise, it is set when sending a shutdown message. Calling this method
1241                 // outside of those situations will fail.
1242                 self.shutdown_scriptpubkey.clone().unwrap().into_inner()
1243         }
1244
1245         #[inline]
1246         fn get_closing_transaction_weight(&self, a_scriptpubkey: Option<&Script>, b_scriptpubkey: Option<&Script>) -> u64 {
1247                 let mut ret =
1248                 (4 +                                           // version
1249                  1 +                                           // input count
1250                  36 +                                          // prevout
1251                  1 +                                           // script length (0)
1252                  4 +                                           // sequence
1253                  1 +                                           // output count
1254                  4                                             // lock time
1255                  )*4 +                                         // * 4 for non-witness parts
1256                 2 +                                            // witness marker and flag
1257                 1 +                                            // witness element count
1258                 4 +                                            // 4 element lengths (2 sigs, multisig dummy, and witness script)
1259                 self.get_funding_redeemscript().len() as u64 + // funding witness script
1260                 2*(1 + 71);                                    // two signatures + sighash type flags
1261                 if let Some(spk) = a_scriptpubkey {
1262                         ret += ((8+1) +                            // output values and script length
1263                                 spk.len() as u64) * 4;                 // scriptpubkey and witness multiplier
1264                 }
1265                 if let Some(spk) = b_scriptpubkey {
1266                         ret += ((8+1) +                            // output values and script length
1267                                 spk.len() as u64) * 4;                 // scriptpubkey and witness multiplier
1268                 }
1269                 ret
1270         }
1271
1272         #[inline]
1273         fn build_closing_transaction(&self, proposed_total_fee_satoshis: u64, skip_remote_output: bool) -> (ClosingTransaction, u64) {
1274                 assert!(self.pending_inbound_htlcs.is_empty());
1275                 assert!(self.pending_outbound_htlcs.is_empty());
1276                 assert!(self.pending_update_fee.is_none());
1277
1278                 let mut total_fee_satoshis = proposed_total_fee_satoshis;
1279                 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 };
1280                 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 };
1281
1282                 if value_to_holder < 0 {
1283                         assert!(self.is_outbound());
1284                         total_fee_satoshis += (-value_to_holder) as u64;
1285                 } else if value_to_counterparty < 0 {
1286                         assert!(!self.is_outbound());
1287                         total_fee_satoshis += (-value_to_counterparty) as u64;
1288                 }
1289
1290                 if skip_remote_output || value_to_counterparty as u64 <= self.holder_dust_limit_satoshis {
1291                         value_to_counterparty = 0;
1292                 }
1293
1294                 if value_to_holder as u64 <= self.holder_dust_limit_satoshis {
1295                         value_to_holder = 0;
1296                 }
1297
1298                 assert!(self.shutdown_scriptpubkey.is_some());
1299                 let holder_shutdown_script = self.get_closing_scriptpubkey();
1300                 let counterparty_shutdown_script = self.counterparty_shutdown_scriptpubkey.clone().unwrap();
1301                 let funding_outpoint = self.funding_outpoint().into_bitcoin_outpoint();
1302
1303                 let closing_transaction = ClosingTransaction::new(value_to_holder as u64, value_to_counterparty as u64, holder_shutdown_script, counterparty_shutdown_script, funding_outpoint);
1304                 (closing_transaction, total_fee_satoshis)
1305         }
1306
1307         fn funding_outpoint(&self) -> OutPoint {
1308                 self.channel_transaction_parameters.funding_outpoint.unwrap()
1309         }
1310
1311         #[inline]
1312         /// Creates a set of keys for build_commitment_transaction to generate a transaction which our
1313         /// counterparty will sign (ie DO NOT send signatures over a transaction created by this to
1314         /// our counterparty!)
1315         /// The result is a transaction which we can revoke broadcastership of (ie a "local" transaction)
1316         /// TODO Some magic rust shit to compile-time check this?
1317         fn build_holder_transaction_keys(&self, commitment_number: u64) -> Result<TxCreationKeys, ChannelError> {
1318                 let per_commitment_point = self.holder_signer.get_per_commitment_point(commitment_number, &self.secp_ctx);
1319                 let delayed_payment_base = &self.get_holder_pubkeys().delayed_payment_basepoint;
1320                 let htlc_basepoint = &self.get_holder_pubkeys().htlc_basepoint;
1321                 let counterparty_pubkeys = self.get_counterparty_pubkeys();
1322
1323                 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()))
1324         }
1325
1326         #[inline]
1327         /// Creates a set of keys for build_commitment_transaction to generate a transaction which we
1328         /// will sign and send to our counterparty.
1329         /// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
1330         fn build_remote_transaction_keys(&self) -> Result<TxCreationKeys, ChannelError> {
1331                 //TODO: Ensure that the payment_key derived here ends up in the library users' wallet as we
1332                 //may see payments to it!
1333                 let revocation_basepoint = &self.get_holder_pubkeys().revocation_basepoint;
1334                 let htlc_basepoint = &self.get_holder_pubkeys().htlc_basepoint;
1335                 let counterparty_pubkeys = self.get_counterparty_pubkeys();
1336
1337                 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()))
1338         }
1339
1340         /// Gets the redeemscript for the funding transaction output (ie the funding transaction output
1341         /// pays to get_funding_redeemscript().to_v0_p2wsh()).
1342         /// Panics if called before accept_channel/new_from_req
1343         pub fn get_funding_redeemscript(&self) -> Script {
1344                 make_funding_redeemscript(&self.get_holder_pubkeys().funding_pubkey, self.counterparty_funding_pubkey())
1345         }
1346
1347         fn get_update_fulfill_htlc<L: Deref>(&mut self, htlc_id_arg: u64, payment_preimage_arg: PaymentPreimage, logger: &L) -> UpdateFulfillFetch where L::Target: Logger {
1348                 // Either ChannelFunded got set (which means it won't be unset) or there is no way any
1349                 // caller thought we could have something claimed (cause we wouldn't have accepted in an
1350                 // incoming HTLC anyway). If we got to ShutdownComplete, callers aren't allowed to call us,
1351                 // either.
1352                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1353                         panic!("Was asked to fulfill an HTLC when channel was not in an operational state");
1354                 }
1355                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
1356
1357                 let payment_hash_calc = PaymentHash(Sha256::hash(&payment_preimage_arg.0[..]).into_inner());
1358
1359                 // ChannelManager may generate duplicate claims/fails due to HTLC update events from
1360                 // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
1361                 // these, but for now we just have to treat them as normal.
1362
1363                 let mut pending_idx = core::usize::MAX;
1364                 let mut htlc_value_msat = 0;
1365                 for (idx, htlc) in self.pending_inbound_htlcs.iter().enumerate() {
1366                         if htlc.htlc_id == htlc_id_arg {
1367                                 assert_eq!(htlc.payment_hash, payment_hash_calc);
1368                                 match htlc.state {
1369                                         InboundHTLCState::Committed => {},
1370                                         InboundHTLCState::LocalRemoved(ref reason) => {
1371                                                 if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
1372                                                 } else {
1373                                                         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()));
1374                                                         debug_assert!(false, "Tried to fulfill an HTLC that was already failed");
1375                                                 }
1376                                                 return UpdateFulfillFetch::DuplicateClaim {};
1377                                         },
1378                                         _ => {
1379                                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1380                                                 // Don't return in release mode here so that we can update channel_monitor
1381                                         }
1382                                 }
1383                                 pending_idx = idx;
1384                                 htlc_value_msat = htlc.amount_msat;
1385                                 break;
1386                         }
1387                 }
1388                 if pending_idx == core::usize::MAX {
1389                         #[cfg(any(test, feature = "fuzztarget"))]
1390                         // If we failed to find an HTLC to fulfill, make sure it was previously fulfilled and
1391                         // this is simply a duplicate claim, not previously failed and we lost funds.
1392                         debug_assert!(self.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
1393                         return UpdateFulfillFetch::DuplicateClaim {};
1394                 }
1395
1396                 // Now update local state:
1397                 //
1398                 // We have to put the payment_preimage in the channel_monitor right away here to ensure we
1399                 // can claim it even if the channel hits the chain before we see their next commitment.
1400                 self.latest_monitor_update_id += 1;
1401                 let monitor_update = ChannelMonitorUpdate {
1402                         update_id: self.latest_monitor_update_id,
1403                         updates: vec![ChannelMonitorUpdateStep::PaymentPreimage {
1404                                 payment_preimage: payment_preimage_arg.clone(),
1405                         }],
1406                 };
1407
1408                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
1409                         for pending_update in self.holding_cell_htlc_updates.iter() {
1410                                 match pending_update {
1411                                         &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
1412                                                 if htlc_id_arg == htlc_id {
1413                                                         // Make sure we don't leave latest_monitor_update_id incremented here:
1414                                                         self.latest_monitor_update_id -= 1;
1415                                                         #[cfg(any(test, feature = "fuzztarget"))]
1416                                                         debug_assert!(self.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
1417                                                         return UpdateFulfillFetch::DuplicateClaim {};
1418                                                 }
1419                                         },
1420                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
1421                                                 if htlc_id_arg == htlc_id {
1422                                                         log_warn!(logger, "Have preimage and want to fulfill HTLC with pending failure against channel {}", log_bytes!(self.channel_id()));
1423                                                         // TODO: We may actually be able to switch to a fulfill here, though its
1424                                                         // rare enough it may not be worth the complexity burden.
1425                                                         debug_assert!(false, "Tried to fulfill an HTLC that was already failed");
1426                                                         return UpdateFulfillFetch::NewClaim { monitor_update, htlc_value_msat, msg: None };
1427                                                 }
1428                                         },
1429                                         _ => {}
1430                                 }
1431                         }
1432                         log_trace!(logger, "Adding HTLC claim to holding_cell in channel {}! Current state: {}", log_bytes!(self.channel_id()), self.channel_state);
1433                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::ClaimHTLC {
1434                                 payment_preimage: payment_preimage_arg, htlc_id: htlc_id_arg,
1435                         });
1436                         #[cfg(any(test, feature = "fuzztarget"))]
1437                         self.historical_inbound_htlc_fulfills.insert(htlc_id_arg);
1438                         return UpdateFulfillFetch::NewClaim { monitor_update, htlc_value_msat, msg: None };
1439                 }
1440                 #[cfg(any(test, feature = "fuzztarget"))]
1441                 self.historical_inbound_htlc_fulfills.insert(htlc_id_arg);
1442
1443                 {
1444                         let htlc = &mut self.pending_inbound_htlcs[pending_idx];
1445                         if let InboundHTLCState::Committed = htlc.state {
1446                         } else {
1447                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1448                                 return UpdateFulfillFetch::NewClaim { monitor_update, htlc_value_msat, msg: None };
1449                         }
1450                         log_trace!(logger, "Upgrading HTLC {} to LocalRemoved with a Fulfill in channel {}!", log_bytes!(htlc.payment_hash.0), log_bytes!(self.channel_id));
1451                         htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::Fulfill(payment_preimage_arg.clone()));
1452                 }
1453
1454                 UpdateFulfillFetch::NewClaim {
1455                         monitor_update,
1456                         htlc_value_msat,
1457                         msg: Some(msgs::UpdateFulfillHTLC {
1458                                 channel_id: self.channel_id(),
1459                                 htlc_id: htlc_id_arg,
1460                                 payment_preimage: payment_preimage_arg,
1461                         }),
1462                 }
1463         }
1464
1465         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 {
1466                 match self.get_update_fulfill_htlc(htlc_id, payment_preimage, logger) {
1467                         UpdateFulfillFetch::NewClaim { mut monitor_update, htlc_value_msat, msg: Some(update_fulfill_htlc) } => {
1468                                 let (commitment, mut additional_update) = match self.send_commitment_no_status_check(logger) {
1469                                         Err(e) => return Err((e, monitor_update)),
1470                                         Ok(res) => res
1471                                 };
1472                                 // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
1473                                 // strictly increasing by one, so decrement it here.
1474                                 self.latest_monitor_update_id = monitor_update.update_id;
1475                                 monitor_update.updates.append(&mut additional_update.updates);
1476                                 Ok(UpdateFulfillCommitFetch::NewClaim { monitor_update, htlc_value_msat, msgs: Some((update_fulfill_htlc, commitment)) })
1477                         },
1478                         UpdateFulfillFetch::NewClaim { monitor_update, htlc_value_msat, msg: None } =>
1479                                 Ok(UpdateFulfillCommitFetch::NewClaim { monitor_update, htlc_value_msat, msgs: None }),
1480                         UpdateFulfillFetch::DuplicateClaim {} => Ok(UpdateFulfillCommitFetch::DuplicateClaim {}),
1481                 }
1482         }
1483
1484         /// We can only have one resolution per HTLC. In some cases around reconnect, we may fulfill
1485         /// an HTLC more than once or fulfill once and then attempt to fail after reconnect. We cannot,
1486         /// however, fail more than once as we wait for an upstream failure to be irrevocably committed
1487         /// before we fail backwards.
1488         /// If we do fail twice, we debug_assert!(false) and return Ok(None). Thus, will always return
1489         /// Ok(_) if debug assertions are turned on or preconditions are met.
1490         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 {
1491                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1492                         panic!("Was asked to fail an HTLC when channel was not in an operational state");
1493                 }
1494                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
1495
1496                 // ChannelManager may generate duplicate claims/fails due to HTLC update events from
1497                 // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
1498                 // these, but for now we just have to treat them as normal.
1499
1500                 let mut pending_idx = core::usize::MAX;
1501                 for (idx, htlc) in self.pending_inbound_htlcs.iter().enumerate() {
1502                         if htlc.htlc_id == htlc_id_arg {
1503                                 match htlc.state {
1504                                         InboundHTLCState::Committed => {},
1505                                         InboundHTLCState::LocalRemoved(ref reason) => {
1506                                                 if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
1507                                                 } else {
1508                                                         debug_assert!(false, "Tried to fail an HTLC that was already failed");
1509                                                 }
1510                                                 return Ok(None);
1511                                         },
1512                                         _ => {
1513                                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1514                                                 return Err(ChannelError::Ignore(format!("Unable to find a pending HTLC which matched the given HTLC ID ({})", htlc.htlc_id)));
1515                                         }
1516                                 }
1517                                 pending_idx = idx;
1518                         }
1519                 }
1520                 if pending_idx == core::usize::MAX {
1521                         #[cfg(any(test, feature = "fuzztarget"))]
1522                         // If we failed to find an HTLC to fail, make sure it was previously fulfilled and this
1523                         // is simply a duplicate fail, not previously failed and we failed-back too early.
1524                         debug_assert!(self.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
1525                         return Ok(None);
1526                 }
1527
1528                 // Now update local state:
1529                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
1530                         for pending_update in self.holding_cell_htlc_updates.iter() {
1531                                 match pending_update {
1532                                         &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
1533                                                 if htlc_id_arg == htlc_id {
1534                                                         #[cfg(any(test, feature = "fuzztarget"))]
1535                                                         debug_assert!(self.historical_inbound_htlc_fulfills.contains(&htlc_id_arg));
1536                                                         return Ok(None);
1537                                                 }
1538                                         },
1539                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
1540                                                 if htlc_id_arg == htlc_id {
1541                                                         debug_assert!(false, "Tried to fail an HTLC that was already failed");
1542                                                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
1543                                                 }
1544                                         },
1545                                         _ => {}
1546                                 }
1547                         }
1548                         log_trace!(logger, "Placing failure for HTLC ID {} in holding cell in channel {}.", htlc_id_arg, log_bytes!(self.channel_id()));
1549                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::FailHTLC {
1550                                 htlc_id: htlc_id_arg,
1551                                 err_packet,
1552                         });
1553                         return Ok(None);
1554                 }
1555
1556                 log_trace!(logger, "Failing HTLC ID {} back with a update_fail_htlc message in channel {}.", htlc_id_arg, log_bytes!(self.channel_id()));
1557                 {
1558                         let htlc = &mut self.pending_inbound_htlcs[pending_idx];
1559                         htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(err_packet.clone()));
1560                 }
1561
1562                 Ok(Some(msgs::UpdateFailHTLC {
1563                         channel_id: self.channel_id(),
1564                         htlc_id: htlc_id_arg,
1565                         reason: err_packet
1566                 }))
1567         }
1568
1569         // Message handlers:
1570
1571         pub fn accept_channel(&mut self, msg: &msgs::AcceptChannel, config: &UserConfig, their_features: &InitFeatures) -> Result<(), ChannelError> {
1572                 // Check sanity of message fields:
1573                 if !self.is_outbound() {
1574                         return Err(ChannelError::Close("Got an accept_channel message from an inbound peer".to_owned()));
1575                 }
1576                 if self.channel_state != ChannelState::OurInitSent as u32 {
1577                         return Err(ChannelError::Close("Got an accept_channel message at a strange time".to_owned()));
1578                 }
1579                 if msg.dust_limit_satoshis > 21000000 * 100000000 {
1580                         return Err(ChannelError::Close(format!("Peer never wants payout outputs? dust_limit_satoshis was {}", msg.dust_limit_satoshis)));
1581                 }
1582                 if msg.channel_reserve_satoshis > self.channel_value_satoshis {
1583                         return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must not be greater than ({})", msg.channel_reserve_satoshis, self.channel_value_satoshis)));
1584                 }
1585                 if msg.channel_reserve_satoshis < self.holder_dust_limit_satoshis {
1586                         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)));
1587                 }
1588                 let remote_reserve = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis);
1589                 if msg.dust_limit_satoshis > remote_reserve {
1590                         return Err(ChannelError::Close(format!("Dust limit ({}) is bigger than our channel reserve ({})", msg.dust_limit_satoshis, remote_reserve)));
1591                 }
1592                 let full_channel_value_msat = (self.channel_value_satoshis - msg.channel_reserve_satoshis) * 1000;
1593                 if msg.htlc_minimum_msat >= full_channel_value_msat {
1594                         return Err(ChannelError::Close(format!("Minimum htlc value ({}) is full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat)));
1595                 }
1596                 let max_delay_acceptable = u16::min(config.peer_channel_config_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
1597                 if msg.to_self_delay > max_delay_acceptable {
1598                         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)));
1599                 }
1600                 if msg.max_accepted_htlcs < 1 {
1601                         return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel".to_owned()));
1602                 }
1603                 if msg.max_accepted_htlcs > MAX_HTLCS {
1604                         return Err(ChannelError::Close(format!("max_accepted_htlcs was {}. It must not be larger than {}", msg.max_accepted_htlcs, MAX_HTLCS)));
1605                 }
1606
1607                 // Now check against optional parameters as set by config...
1608                 if msg.htlc_minimum_msat > config.peer_channel_config_limits.max_htlc_minimum_msat {
1609                         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)));
1610                 }
1611                 if msg.max_htlc_value_in_flight_msat < config.peer_channel_config_limits.min_max_htlc_value_in_flight_msat {
1612                         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)));
1613                 }
1614                 if msg.channel_reserve_satoshis > config.peer_channel_config_limits.max_channel_reserve_satoshis {
1615                         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)));
1616                 }
1617                 if msg.max_accepted_htlcs < config.peer_channel_config_limits.min_max_accepted_htlcs {
1618                         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)));
1619                 }
1620                 if msg.dust_limit_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
1621                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the implementation limit ({})", msg.dust_limit_satoshis, MIN_CHAN_DUST_LIMIT_SATOSHIS)));
1622                 }
1623                 if msg.dust_limit_satoshis > MAX_CHAN_DUST_LIMIT_SATOSHIS {
1624                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the implementation limit ({})", msg.dust_limit_satoshis, MAX_CHAN_DUST_LIMIT_SATOSHIS)));
1625                 }
1626                 if msg.minimum_depth > config.peer_channel_config_limits.max_minimum_depth {
1627                         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)));
1628                 }
1629                 if msg.minimum_depth == 0 {
1630                         // Note that if this changes we should update the serialization minimum version to
1631                         // indicate to older clients that they don't understand some features of the current
1632                         // channel.
1633                         return Err(ChannelError::Close("Minimum confirmation depth must be at least 1".to_owned()));
1634                 }
1635
1636                 let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() {
1637                         match &msg.shutdown_scriptpubkey {
1638                                 &OptionalField::Present(ref script) => {
1639                                         // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything
1640                                         if script.len() == 0 {
1641                                                 None
1642                                         } else {
1643                                                 if !script::is_bolt2_compliant(&script, their_features) {
1644                                                         return Err(ChannelError::Close(format!("Peer is signaling upfront_shutdown but has provided an unacceptable scriptpubkey format: {}", script)));
1645                                                 }
1646                                                 Some(script.clone())
1647                                         }
1648                                 },
1649                                 // 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
1650                                 &OptionalField::Absent => {
1651                                         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()));
1652                                 }
1653                         }
1654                 } else { None };
1655
1656                 self.counterparty_dust_limit_satoshis = msg.dust_limit_satoshis;
1657                 self.counterparty_max_htlc_value_in_flight_msat = cmp::min(msg.max_htlc_value_in_flight_msat, self.channel_value_satoshis * 1000);
1658                 self.counterparty_selected_channel_reserve_satoshis = Some(msg.channel_reserve_satoshis);
1659                 self.counterparty_htlc_minimum_msat = msg.htlc_minimum_msat;
1660                 self.counterparty_max_accepted_htlcs = msg.max_accepted_htlcs;
1661                 self.minimum_depth = Some(msg.minimum_depth);
1662
1663                 let counterparty_pubkeys = ChannelPublicKeys {
1664                         funding_pubkey: msg.funding_pubkey,
1665                         revocation_basepoint: msg.revocation_basepoint,
1666                         payment_point: msg.payment_point,
1667                         delayed_payment_basepoint: msg.delayed_payment_basepoint,
1668                         htlc_basepoint: msg.htlc_basepoint
1669                 };
1670
1671                 self.channel_transaction_parameters.counterparty_parameters = Some(CounterpartyChannelTransactionParameters {
1672                         selected_contest_delay: msg.to_self_delay,
1673                         pubkeys: counterparty_pubkeys,
1674                 });
1675
1676                 self.counterparty_cur_commitment_point = Some(msg.first_per_commitment_point);
1677                 self.counterparty_shutdown_scriptpubkey = counterparty_shutdown_scriptpubkey;
1678
1679                 self.channel_state = ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32;
1680
1681                 Ok(())
1682         }
1683
1684         fn funding_created_signature<L: Deref>(&mut self, sig: &Signature, logger: &L) -> Result<(Txid, CommitmentTransaction, Signature), ChannelError> where L::Target: Logger {
1685                 let funding_script = self.get_funding_redeemscript();
1686
1687                 let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number)?;
1688                 let initial_commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, false, logger).0;
1689                 {
1690                         let trusted_tx = initial_commitment_tx.trust();
1691                         let initial_commitment_bitcoin_tx = trusted_tx.built_transaction();
1692                         let sighash = initial_commitment_bitcoin_tx.get_sighash_all(&funding_script, self.channel_value_satoshis);
1693                         // They sign the holder commitment transaction...
1694                         log_trace!(logger, "Checking funding_created tx signature {} by key {} against tx {} (sighash {}) with redeemscript {} for channel {}.",
1695                                 log_bytes!(sig.serialize_compact()[..]), log_bytes!(self.counterparty_funding_pubkey().serialize()),
1696                                 encode::serialize_hex(&initial_commitment_bitcoin_tx.transaction), log_bytes!(sighash[..]),
1697                                 encode::serialize_hex(&funding_script), log_bytes!(self.channel_id()));
1698                         secp_check!(self.secp_ctx.verify(&sighash, &sig, self.counterparty_funding_pubkey()), "Invalid funding_created signature from peer".to_owned());
1699                 }
1700
1701                 let counterparty_keys = self.build_remote_transaction_keys()?;
1702                 let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).0;
1703
1704                 let counterparty_trusted_tx = counterparty_initial_commitment_tx.trust();
1705                 let counterparty_initial_bitcoin_tx = counterparty_trusted_tx.built_transaction();
1706                 log_trace!(logger, "Initial counterparty tx for channel {} is: txid {} tx {}",
1707                         log_bytes!(self.channel_id()), counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
1708
1709                 let counterparty_signature = self.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, &self.secp_ctx)
1710                                 .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0;
1711
1712                 // We sign "counterparty" commitment transaction, allowing them to broadcast the tx if they wish.
1713                 Ok((counterparty_initial_bitcoin_tx.txid, initial_commitment_tx, counterparty_signature))
1714         }
1715
1716         fn counterparty_funding_pubkey(&self) -> &PublicKey {
1717                 &self.get_counterparty_pubkeys().funding_pubkey
1718         }
1719
1720         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 {
1721                 if self.is_outbound() {
1722                         return Err(ChannelError::Close("Received funding_created for an outbound channel?".to_owned()));
1723                 }
1724                 if self.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
1725                         // BOLT 2 says that if we disconnect before we send funding_signed we SHOULD NOT
1726                         // remember the channel, so it's safe to just send an error_message here and drop the
1727                         // channel.
1728                         return Err(ChannelError::Close("Received funding_created after we got the channel!".to_owned()));
1729                 }
1730                 if self.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
1731                                 self.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
1732                                 self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
1733                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
1734                 }
1735
1736                 let funding_txo = OutPoint { txid: msg.funding_txid, index: msg.funding_output_index };
1737                 self.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
1738                 // This is an externally observable change before we finish all our checks.  In particular
1739                 // funding_created_signature may fail.
1740                 self.holder_signer.ready_channel(&self.channel_transaction_parameters);
1741
1742                 let (counterparty_initial_commitment_txid, initial_commitment_tx, signature) = match self.funding_created_signature(&msg.signature, logger) {
1743                         Ok(res) => res,
1744                         Err(ChannelError::Close(e)) => {
1745                                 self.channel_transaction_parameters.funding_outpoint = None;
1746                                 return Err(ChannelError::Close(e));
1747                         },
1748                         Err(e) => {
1749                                 // The only error we know how to handle is ChannelError::Close, so we fall over here
1750                                 // to make sure we don't continue with an inconsistent state.
1751                                 panic!("unexpected error type from funding_created_signature {:?}", e);
1752                         }
1753                 };
1754
1755                 let holder_commitment_tx = HolderCommitmentTransaction::new(
1756                         initial_commitment_tx,
1757                         msg.signature,
1758                         Vec::new(),
1759                         &self.get_holder_pubkeys().funding_pubkey,
1760                         self.counterparty_funding_pubkey()
1761                 );
1762
1763                 self.holder_signer.validate_holder_commitment(&holder_commitment_tx)
1764                         .map_err(|_| ChannelError::Close("Failed to validate our commitment".to_owned()))?;
1765
1766                 // Now that we're past error-generating stuff, update our local state:
1767
1768                 let funding_redeemscript = self.get_funding_redeemscript();
1769                 let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
1770                 let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound());
1771                 let shutdown_script = self.shutdown_scriptpubkey.clone().map(|script| script.into_inner());
1772                 let channel_monitor = ChannelMonitor::new(self.secp_ctx.clone(), self.holder_signer.clone(),
1773                                                           shutdown_script, self.get_holder_selected_contest_delay(),
1774                                                           &self.destination_script, (funding_txo, funding_txo_script.clone()),
1775                                                           &self.channel_transaction_parameters,
1776                                                           funding_redeemscript.clone(), self.channel_value_satoshis,
1777                                                           obscure_factor,
1778                                                           holder_commitment_tx, best_block);
1779
1780                 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);
1781
1782                 self.channel_state = ChannelState::FundingSent as u32;
1783                 self.channel_id = funding_txo.to_channel_id();
1784                 self.cur_counterparty_commitment_transaction_number -= 1;
1785                 self.cur_holder_commitment_transaction_number -= 1;
1786
1787                 log_info!(logger, "Generated funding_signed for peer for channel {}", log_bytes!(self.channel_id()));
1788
1789                 Ok((msgs::FundingSigned {
1790                         channel_id: self.channel_id,
1791                         signature
1792                 }, channel_monitor))
1793         }
1794
1795         /// Handles a funding_signed message from the remote end.
1796         /// If this call is successful, broadcast the funding transaction (and not before!)
1797         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 {
1798                 if !self.is_outbound() {
1799                         return Err(ChannelError::Close("Received funding_signed for an inbound channel?".to_owned()));
1800                 }
1801                 if self.channel_state & !(ChannelState::MonitorUpdateFailed as u32) != ChannelState::FundingCreated as u32 {
1802                         return Err(ChannelError::Close("Received funding_signed in strange state!".to_owned()));
1803                 }
1804                 if self.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
1805                                 self.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
1806                                 self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
1807                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
1808                 }
1809
1810                 let funding_script = self.get_funding_redeemscript();
1811
1812                 let counterparty_keys = self.build_remote_transaction_keys()?;
1813                 let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).0;
1814                 let counterparty_trusted_tx = counterparty_initial_commitment_tx.trust();
1815                 let counterparty_initial_bitcoin_tx = counterparty_trusted_tx.built_transaction();
1816
1817                 log_trace!(logger, "Initial counterparty tx for channel {} is: txid {} tx {}",
1818                         log_bytes!(self.channel_id()), counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
1819
1820                 let holder_signer = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number)?;
1821                 let initial_commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &holder_signer, true, false, logger).0;
1822                 {
1823                         let trusted_tx = initial_commitment_tx.trust();
1824                         let initial_commitment_bitcoin_tx = trusted_tx.built_transaction();
1825                         let sighash = initial_commitment_bitcoin_tx.get_sighash_all(&funding_script, self.channel_value_satoshis);
1826                         // They sign our commitment transaction, allowing us to broadcast the tx if we wish.
1827                         if let Err(_) = self.secp_ctx.verify(&sighash, &msg.signature, &self.get_counterparty_pubkeys().funding_pubkey) {
1828                                 return Err(ChannelError::Close("Invalid funding_signed signature from peer".to_owned()));
1829                         }
1830                 }
1831
1832                 let holder_commitment_tx = HolderCommitmentTransaction::new(
1833                         initial_commitment_tx,
1834                         msg.signature,
1835                         Vec::new(),
1836                         &self.get_holder_pubkeys().funding_pubkey,
1837                         self.counterparty_funding_pubkey()
1838                 );
1839
1840                 self.holder_signer.validate_holder_commitment(&holder_commitment_tx)
1841                         .map_err(|_| ChannelError::Close("Failed to validate our commitment".to_owned()))?;
1842
1843
1844                 let funding_redeemscript = self.get_funding_redeemscript();
1845                 let funding_txo = self.get_funding_txo().unwrap();
1846                 let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
1847                 let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound());
1848                 let shutdown_script = self.shutdown_scriptpubkey.clone().map(|script| script.into_inner());
1849                 let channel_monitor = ChannelMonitor::new(self.secp_ctx.clone(), self.holder_signer.clone(),
1850                                                           shutdown_script, self.get_holder_selected_contest_delay(),
1851                                                           &self.destination_script, (funding_txo, funding_txo_script),
1852                                                           &self.channel_transaction_parameters,
1853                                                           funding_redeemscript.clone(), self.channel_value_satoshis,
1854                                                           obscure_factor,
1855                                                           holder_commitment_tx, best_block);
1856
1857                 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);
1858
1859                 assert_eq!(self.channel_state & (ChannelState::MonitorUpdateFailed as u32), 0); // We have no had any monitor(s) yet to fail update!
1860                 self.channel_state = ChannelState::FundingSent as u32;
1861                 self.cur_holder_commitment_transaction_number -= 1;
1862                 self.cur_counterparty_commitment_transaction_number -= 1;
1863
1864                 log_info!(logger, "Received funding_signed from peer for channel {}", log_bytes!(self.channel_id()));
1865
1866                 Ok((channel_monitor, self.funding_transaction.as_ref().cloned().unwrap()))
1867         }
1868
1869         pub fn funding_locked<L: Deref>(&mut self, msg: &msgs::FundingLocked, logger: &L) -> Result<(), ChannelError> where L::Target: Logger {
1870                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
1871                         self.workaround_lnd_bug_4006 = Some(msg.clone());
1872                         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()));
1873                 }
1874
1875                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
1876
1877                 if non_shutdown_state == ChannelState::FundingSent as u32 {
1878                         self.channel_state |= ChannelState::TheirFundingLocked as u32;
1879                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) {
1880                         self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
1881                         self.update_time_counter += 1;
1882                 } else if (self.channel_state & (ChannelState::ChannelFunded as u32) != 0 &&
1883                                  // Note that funding_signed/funding_created will have decremented both by 1!
1884                                  self.cur_holder_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1 &&
1885                                  self.cur_counterparty_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1) ||
1886                                 // If we reconnected before sending our funding locked they may still resend theirs:
1887                                 (self.channel_state & (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32) ==
1888                                                       (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32)) {
1889                         if self.counterparty_cur_commitment_point != Some(msg.next_per_commitment_point) {
1890                                 return Err(ChannelError::Close("Peer sent a reconnect funding_locked with a different point".to_owned()));
1891                         }
1892                         // They probably disconnected/reconnected and re-sent the funding_locked, which is required
1893                         return Ok(());
1894                 } else {
1895                         return Err(ChannelError::Close("Peer sent a funding_locked at a strange time".to_owned()));
1896                 }
1897
1898                 self.counterparty_prev_commitment_point = self.counterparty_cur_commitment_point;
1899                 self.counterparty_cur_commitment_point = Some(msg.next_per_commitment_point);
1900
1901                 log_info!(logger, "Received funding_locked from peer for channel {}", log_bytes!(self.channel_id()));
1902
1903                 Ok(())
1904         }
1905
1906         /// Returns a HTLCStats about inbound pending htlcs
1907         fn get_inbound_pending_htlc_stats(&self) -> HTLCStats {
1908                 let mut stats = HTLCStats {
1909                         pending_htlcs: self.pending_inbound_htlcs.len() as u32,
1910                         pending_htlcs_value_msat: 0,
1911                         on_counterparty_tx_dust_exposure_msat: 0,
1912                         on_holder_tx_dust_exposure_msat: 0,
1913                 };
1914
1915                 let counterparty_dust_limit_timeout_sat = (self.get_dust_buffer_feerate() as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
1916                 let holder_dust_limit_success_sat = (self.get_dust_buffer_feerate() as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
1917                 for ref htlc in self.pending_inbound_htlcs.iter() {
1918                         stats.pending_htlcs_value_msat += htlc.amount_msat;
1919                         if htlc.amount_msat / 1000 < counterparty_dust_limit_timeout_sat {
1920                                 stats.on_counterparty_tx_dust_exposure_msat += htlc.amount_msat;
1921                         }
1922                         if htlc.amount_msat / 1000 < holder_dust_limit_success_sat {
1923                                 stats.on_holder_tx_dust_exposure_msat += htlc.amount_msat;
1924                         }
1925                 }
1926                 stats
1927         }
1928
1929         /// Returns a HTLCStats about pending outbound htlcs, *including* pending adds in our holding cell.
1930         fn get_outbound_pending_htlc_stats(&self) -> HTLCStats {
1931                 let mut stats = HTLCStats {
1932                         pending_htlcs: self.pending_outbound_htlcs.len() as u32,
1933                         pending_htlcs_value_msat: 0,
1934                         on_counterparty_tx_dust_exposure_msat: 0,
1935                         on_holder_tx_dust_exposure_msat: 0,
1936                 };
1937
1938                 let counterparty_dust_limit_success_sat = (self.get_dust_buffer_feerate() as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
1939                 let holder_dust_limit_timeout_sat = (self.get_dust_buffer_feerate() as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
1940                 for ref htlc in self.pending_outbound_htlcs.iter() {
1941                         stats.pending_htlcs_value_msat += htlc.amount_msat;
1942                         if htlc.amount_msat / 1000 < counterparty_dust_limit_success_sat {
1943                                 stats.on_counterparty_tx_dust_exposure_msat += htlc.amount_msat;
1944                         }
1945                         if htlc.amount_msat / 1000 < holder_dust_limit_timeout_sat {
1946                                 stats.on_holder_tx_dust_exposure_msat += htlc.amount_msat;
1947                         }
1948                 }
1949
1950                 for update in self.holding_cell_htlc_updates.iter() {
1951                         if let &HTLCUpdateAwaitingACK::AddHTLC { ref amount_msat, .. } = update {
1952                                 stats.pending_htlcs += 1;
1953                                 stats.pending_htlcs_value_msat += amount_msat;
1954                                 if *amount_msat / 1000 < counterparty_dust_limit_success_sat {
1955                                         stats.on_counterparty_tx_dust_exposure_msat += amount_msat;
1956                                 }
1957                                 if *amount_msat / 1000 < holder_dust_limit_timeout_sat {
1958                                         stats.on_holder_tx_dust_exposure_msat += amount_msat;
1959                                 }
1960                         }
1961                 }
1962                 stats
1963         }
1964
1965         /// Get the available (ie not including pending HTLCs) inbound and outbound balance in msat.
1966         /// Doesn't bother handling the
1967         /// if-we-removed-it-already-but-haven't-fully-resolved-they-can-still-send-an-inbound-HTLC
1968         /// corner case properly.
1969         pub fn get_inbound_outbound_available_balance_msat(&self) -> (u64, u64) {
1970                 // Note that we have to handle overflow due to the above case.
1971                 (
1972                         cmp::max(self.channel_value_satoshis as i64 * 1000
1973                                 - self.value_to_self_msat as i64
1974                                 - self.get_inbound_pending_htlc_stats().pending_htlcs_value_msat as i64
1975                                 - Self::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis) as i64 * 1000,
1976                         0) as u64,
1977                         cmp::max(self.value_to_self_msat as i64
1978                                 - self.get_outbound_pending_htlc_stats().pending_htlcs_value_msat as i64
1979                                 - self.counterparty_selected_channel_reserve_satoshis.unwrap_or(0) as i64 * 1000,
1980                         0) as u64
1981                 )
1982         }
1983
1984         pub fn get_holder_counterparty_selected_channel_reserve_satoshis(&self) -> (u64, Option<u64>) {
1985                 (Self::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis),
1986                 self.counterparty_selected_channel_reserve_satoshis)
1987         }
1988
1989         // Get the fee cost of a commitment tx with a given number of HTLC outputs.
1990         // Note that num_htlcs should not include dust HTLCs.
1991         fn commit_tx_fee_msat(&self, num_htlcs: usize) -> u64 {
1992                 // Note that we need to divide before multiplying to round properly,
1993                 // since the lowest denomination of bitcoin on-chain is the satoshi.
1994                 (COMMITMENT_TX_BASE_WEIGHT + num_htlcs as u64 * COMMITMENT_TX_WEIGHT_PER_HTLC) * self.feerate_per_kw as u64 / 1000 * 1000
1995         }
1996
1997         // Get the commitment tx fee for the local's (i.e. our) next commitment transaction based on the
1998         // number of pending HTLCs that are on track to be in our next commitment tx, plus an additional
1999         // HTLC if `fee_spike_buffer_htlc` is Some, plus a new HTLC given by `new_htlc_amount`. Dust HTLCs
2000         // are excluded.
2001         fn next_local_commit_tx_fee_msat(&self, htlc: HTLCCandidate, fee_spike_buffer_htlc: Option<()>) -> u64 {
2002                 assert!(self.is_outbound());
2003
2004                 let real_dust_limit_success_sat = (self.feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
2005                 let real_dust_limit_timeout_sat = (self.feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
2006
2007                 let mut addl_htlcs = 0;
2008                 if fee_spike_buffer_htlc.is_some() { addl_htlcs += 1; }
2009                 match htlc.origin {
2010                         HTLCInitiator::LocalOffered => {
2011                                 if htlc.amount_msat / 1000 >= real_dust_limit_timeout_sat {
2012                                         addl_htlcs += 1;
2013                                 }
2014                         },
2015                         HTLCInitiator::RemoteOffered => {
2016                                 if htlc.amount_msat / 1000 >= real_dust_limit_success_sat {
2017                                         addl_htlcs += 1;
2018                                 }
2019                         }
2020                 }
2021
2022                 let mut included_htlcs = 0;
2023                 for ref htlc in self.pending_inbound_htlcs.iter() {
2024                         if htlc.amount_msat / 1000 < real_dust_limit_success_sat {
2025                                 continue
2026                         }
2027                         // We include LocalRemoved HTLCs here because we may still need to broadcast a commitment
2028                         // transaction including this HTLC if it times out before they RAA.
2029                         included_htlcs += 1;
2030                 }
2031
2032                 for ref htlc in self.pending_outbound_htlcs.iter() {
2033                         if htlc.amount_msat / 1000 < real_dust_limit_timeout_sat {
2034                                 continue
2035                         }
2036                         match htlc.state {
2037                                 OutboundHTLCState::LocalAnnounced {..} => included_htlcs += 1,
2038                                 OutboundHTLCState::Committed => included_htlcs += 1,
2039                                 OutboundHTLCState::RemoteRemoved {..} => included_htlcs += 1,
2040                                 // We don't include AwaitingRemoteRevokeToRemove HTLCs because our next commitment
2041                                 // transaction won't be generated until they send us their next RAA, which will mean
2042                                 // dropping any HTLCs in this state.
2043                                 _ => {},
2044                         }
2045                 }
2046
2047                 for htlc in self.holding_cell_htlc_updates.iter() {
2048                         match htlc {
2049                                 &HTLCUpdateAwaitingACK::AddHTLC { amount_msat, .. } => {
2050                                         if amount_msat / 1000 < real_dust_limit_timeout_sat {
2051                                                 continue
2052                                         }
2053                                         included_htlcs += 1
2054                                 },
2055                                 _ => {}, // Don't include claims/fails that are awaiting ack, because once we get the
2056                                          // ack we're guaranteed to never include them in commitment txs anymore.
2057                         }
2058                 }
2059
2060                 let num_htlcs = included_htlcs + addl_htlcs;
2061                 let res = self.commit_tx_fee_msat(num_htlcs);
2062                 #[cfg(any(test, feature = "fuzztarget"))]
2063                 {
2064                         let mut fee = res;
2065                         if fee_spike_buffer_htlc.is_some() {
2066                                 fee = self.commit_tx_fee_msat(num_htlcs - 1);
2067                         }
2068                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len()
2069                                 + self.holding_cell_htlc_updates.len();
2070                         let commitment_tx_info = CommitmentTxInfoCached {
2071                                 fee,
2072                                 total_pending_htlcs,
2073                                 next_holder_htlc_id: match htlc.origin {
2074                                         HTLCInitiator::LocalOffered => self.next_holder_htlc_id + 1,
2075                                         HTLCInitiator::RemoteOffered => self.next_holder_htlc_id,
2076                                 },
2077                                 next_counterparty_htlc_id: match htlc.origin {
2078                                         HTLCInitiator::LocalOffered => self.next_counterparty_htlc_id,
2079                                         HTLCInitiator::RemoteOffered => self.next_counterparty_htlc_id + 1,
2080                                 },
2081                                 feerate: self.feerate_per_kw,
2082                         };
2083                         *self.next_local_commitment_tx_fee_info_cached.lock().unwrap() = Some(commitment_tx_info);
2084                 }
2085                 res
2086         }
2087
2088         // Get the commitment tx fee for the remote's next commitment transaction based on the number of
2089         // pending HTLCs that are on track to be in their next commitment tx, plus an additional HTLC if
2090         // `fee_spike_buffer_htlc` is Some, plus a new HTLC given by `new_htlc_amount`. Dust HTLCs are
2091         // excluded.
2092         fn next_remote_commit_tx_fee_msat(&self, htlc: HTLCCandidate, fee_spike_buffer_htlc: Option<()>) -> u64 {
2093                 assert!(!self.is_outbound());
2094
2095                 let real_dust_limit_success_sat = (self.feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
2096                 let real_dust_limit_timeout_sat = (self.feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
2097
2098                 let mut addl_htlcs = 0;
2099                 if fee_spike_buffer_htlc.is_some() { addl_htlcs += 1; }
2100                 match htlc.origin {
2101                         HTLCInitiator::LocalOffered => {
2102                                 if htlc.amount_msat / 1000 >= real_dust_limit_success_sat {
2103                                         addl_htlcs += 1;
2104                                 }
2105                         },
2106                         HTLCInitiator::RemoteOffered => {
2107                                 if htlc.amount_msat / 1000 >= real_dust_limit_timeout_sat {
2108                                         addl_htlcs += 1;
2109                                 }
2110                         }
2111                 }
2112
2113                 // When calculating the set of HTLCs which will be included in their next commitment_signed, all
2114                 // non-dust inbound HTLCs are included (as all states imply it will be included) and only
2115                 // committed outbound HTLCs, see below.
2116                 let mut included_htlcs = 0;
2117                 for ref htlc in self.pending_inbound_htlcs.iter() {
2118                         if htlc.amount_msat / 1000 <= real_dust_limit_timeout_sat {
2119                                 continue
2120                         }
2121                         included_htlcs += 1;
2122                 }
2123
2124                 for ref htlc in self.pending_outbound_htlcs.iter() {
2125                         if htlc.amount_msat / 1000 <= real_dust_limit_success_sat {
2126                                 continue
2127                         }
2128                         // We only include outbound HTLCs if it will not be included in their next commitment_signed,
2129                         // i.e. if they've responded to us with an RAA after announcement.
2130                         match htlc.state {
2131                                 OutboundHTLCState::Committed => included_htlcs += 1,
2132                                 OutboundHTLCState::RemoteRemoved {..} => included_htlcs += 1,
2133                                 OutboundHTLCState::LocalAnnounced { .. } => included_htlcs += 1,
2134                                 _ => {},
2135                         }
2136                 }
2137
2138                 let num_htlcs = included_htlcs + addl_htlcs;
2139                 let res = self.commit_tx_fee_msat(num_htlcs);
2140                 #[cfg(any(test, feature = "fuzztarget"))]
2141                 {
2142                         let mut fee = res;
2143                         if fee_spike_buffer_htlc.is_some() {
2144                                 fee = self.commit_tx_fee_msat(num_htlcs - 1);
2145                         }
2146                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len();
2147                         let commitment_tx_info = CommitmentTxInfoCached {
2148                                 fee,
2149                                 total_pending_htlcs,
2150                                 next_holder_htlc_id: match htlc.origin {
2151                                         HTLCInitiator::LocalOffered => self.next_holder_htlc_id + 1,
2152                                         HTLCInitiator::RemoteOffered => self.next_holder_htlc_id,
2153                                 },
2154                                 next_counterparty_htlc_id: match htlc.origin {
2155                                         HTLCInitiator::LocalOffered => self.next_counterparty_htlc_id,
2156                                         HTLCInitiator::RemoteOffered => self.next_counterparty_htlc_id + 1,
2157                                 },
2158                                 feerate: self.feerate_per_kw,
2159                         };
2160                         *self.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = Some(commitment_tx_info);
2161                 }
2162                 res
2163         }
2164
2165         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>
2166         where F: for<'a> Fn(&'a Self, PendingHTLCStatus, u16) -> PendingHTLCStatus, L::Target: Logger {
2167                 // We can't accept HTLCs sent after we've sent a shutdown.
2168                 let local_sent_shutdown = (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::LocalShutdownSent as u32)) != (ChannelState::ChannelFunded as u32);
2169                 if local_sent_shutdown {
2170                         pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x4000|8);
2171                 }
2172                 // If the remote has sent a shutdown prior to adding this HTLC, then they are in violation of the spec.
2173                 let remote_sent_shutdown = (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::RemoteShutdownSent as u32)) != (ChannelState::ChannelFunded as u32);
2174                 if remote_sent_shutdown {
2175                         return Err(ChannelError::Close("Got add HTLC message when channel was not in an operational state".to_owned()));
2176                 }
2177                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2178                         return Err(ChannelError::Close("Peer sent update_add_htlc when we needed a channel_reestablish".to_owned()));
2179                 }
2180                 if msg.amount_msat > self.channel_value_satoshis * 1000 {
2181                         return Err(ChannelError::Close("Remote side tried to send more than the total value of the channel".to_owned()));
2182                 }
2183                 if msg.amount_msat == 0 {
2184                         return Err(ChannelError::Close("Remote side tried to send a 0-msat HTLC".to_owned()));
2185                 }
2186                 if msg.amount_msat < self.holder_htlc_minimum_msat {
2187                         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)));
2188                 }
2189
2190                 let inbound_stats = self.get_inbound_pending_htlc_stats();
2191                 let outbound_stats = self.get_outbound_pending_htlc_stats();
2192                 if inbound_stats.pending_htlcs + 1 > OUR_MAX_HTLCS as u32 {
2193                         return Err(ChannelError::Close(format!("Remote tried to push more than our max accepted HTLCs ({})", OUR_MAX_HTLCS)));
2194                 }
2195                 let holder_max_htlc_value_in_flight_msat = Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis);
2196                 if inbound_stats.pending_htlcs_value_msat + msg.amount_msat > holder_max_htlc_value_in_flight_msat {
2197                         return Err(ChannelError::Close(format!("Remote HTLC add would put them over our max HTLC value ({})", holder_max_htlc_value_in_flight_msat)));
2198                 }
2199                 // Check holder_selected_channel_reserve_satoshis (we're getting paid, so they have to at least meet
2200                 // the reserve_satoshis we told them to always have as direct payment so that they lose
2201                 // something if we punish them for broadcasting an old state).
2202                 // Note that we don't really care about having a small/no to_remote output in our local
2203                 // commitment transactions, as the purpose of the channel reserve is to ensure we can
2204                 // punish *them* if they misbehave, so we discount any outbound HTLCs which will not be
2205                 // present in the next commitment transaction we send them (at least for fulfilled ones,
2206                 // failed ones won't modify value_to_self).
2207                 // Note that we will send HTLCs which another instance of rust-lightning would think
2208                 // violate the reserve value if we do not do this (as we forget inbound HTLCs from the
2209                 // Channel state once they will not be present in the next received commitment
2210                 // transaction).
2211                 let mut removed_outbound_total_msat = 0;
2212                 for ref htlc in self.pending_outbound_htlcs.iter() {
2213                         if let OutboundHTLCState::AwaitingRemoteRevokeToRemove(None) = htlc.state {
2214                                 removed_outbound_total_msat += htlc.amount_msat;
2215                         } else if let OutboundHTLCState::AwaitingRemovedRemoteRevoke(None) = htlc.state {
2216                                 removed_outbound_total_msat += htlc.amount_msat;
2217                         }
2218                 }
2219
2220                 let exposure_dust_limit_timeout_sats = (self.get_dust_buffer_feerate() as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
2221                 if msg.amount_msat / 1000 < exposure_dust_limit_timeout_sats {
2222                         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;
2223                         if on_counterparty_tx_dust_htlc_exposure_msat > self.get_max_dust_htlc_exposure_msat() {
2224                                 log_info!(logger, "Cannot accept value that would put our exposure to dust HTLCs at {} over the limit {} on counterparty commitment tx",
2225                                         on_counterparty_tx_dust_htlc_exposure_msat, self.get_max_dust_htlc_exposure_msat());
2226                                 pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|7);
2227                         }
2228                 }
2229
2230                 let exposure_dust_limit_success_sats = (self.get_dust_buffer_feerate() as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
2231                 if msg.amount_msat / 1000 < exposure_dust_limit_success_sats {
2232                         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;
2233                         if on_holder_tx_dust_htlc_exposure_msat > self.get_max_dust_htlc_exposure_msat() {
2234                                 log_info!(logger, "Cannot accept value that would put our exposure to dust HTLCs at {} over the limit {} on holder commitment tx",
2235                                         on_holder_tx_dust_htlc_exposure_msat, self.get_max_dust_htlc_exposure_msat());
2236                                 pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|7);
2237                         }
2238                 }
2239
2240                 let pending_value_to_self_msat =
2241                         self.value_to_self_msat + inbound_stats.pending_htlcs_value_msat - removed_outbound_total_msat;
2242                 let pending_remote_value_msat =
2243                         self.channel_value_satoshis * 1000 - pending_value_to_self_msat;
2244                 if pending_remote_value_msat < msg.amount_msat {
2245                         return Err(ChannelError::Close("Remote HTLC add would overdraw remaining funds".to_owned()));
2246                 }
2247
2248                 // Check that the remote can afford to pay for this HTLC on-chain at the current
2249                 // feerate_per_kw, while maintaining their channel reserve (as required by the spec).
2250                 let remote_commit_tx_fee_msat = if self.is_outbound() { 0 } else {
2251                         let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
2252                         self.next_remote_commit_tx_fee_msat(htlc_candidate, None) // Don't include the extra fee spike buffer HTLC in calculations
2253                 };
2254                 if pending_remote_value_msat - msg.amount_msat < remote_commit_tx_fee_msat {
2255                         return Err(ChannelError::Close("Remote HTLC add would not leave enough to pay for fees".to_owned()));
2256                 };
2257
2258                 let chan_reserve_msat =
2259                         Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis) * 1000;
2260                 if pending_remote_value_msat - msg.amount_msat - remote_commit_tx_fee_msat < chan_reserve_msat {
2261                         return Err(ChannelError::Close("Remote HTLC add would put them under remote reserve value".to_owned()));
2262                 }
2263
2264                 if !self.is_outbound() {
2265                         // `2 *` and `Some(())` is for the fee spike buffer we keep for the remote. This deviates from
2266                         // the spec because in the spec, the fee spike buffer requirement doesn't exist on the
2267                         // receiver's side, only on the sender's.
2268                         // Note that when we eventually remove support for fee updates and switch to anchor output
2269                         // fees, we will drop the `2 *`, since we no longer be as sensitive to fee spikes. But, keep
2270                         // the extra htlc when calculating the next remote commitment transaction fee as we should
2271                         // still be able to afford adding this HTLC plus one more future HTLC, regardless of being
2272                         // sensitive to fee spikes.
2273                         let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
2274                         let remote_fee_cost_incl_stuck_buffer_msat = 2 * self.next_remote_commit_tx_fee_msat(htlc_candidate, Some(()));
2275                         if pending_remote_value_msat - msg.amount_msat - chan_reserve_msat < remote_fee_cost_incl_stuck_buffer_msat {
2276                                 // Note that if the pending_forward_status is not updated here, then it's because we're already failing
2277                                 // the HTLC, i.e. its status is already set to failing.
2278                                 log_info!(logger, "Attempting to fail HTLC due to fee spike buffer violation in channel {}. Rebalancing is required.", log_bytes!(self.channel_id()));
2279                                 pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|7);
2280                         }
2281                 } else {
2282                         // Check that they won't violate our local required channel reserve by adding this HTLC.
2283                         let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
2284                         let local_commit_tx_fee_msat = self.next_local_commit_tx_fee_msat(htlc_candidate, None);
2285                         if self.value_to_self_msat < self.counterparty_selected_channel_reserve_satoshis.unwrap() * 1000 + local_commit_tx_fee_msat {
2286                                 return Err(ChannelError::Close("Cannot accept HTLC that would put our balance under counterparty-announced channel reserve value".to_owned()));
2287                         }
2288                 }
2289                 if self.next_counterparty_htlc_id != msg.htlc_id {
2290                         return Err(ChannelError::Close(format!("Remote skipped HTLC ID (skipped ID: {})", self.next_counterparty_htlc_id)));
2291                 }
2292                 if msg.cltv_expiry >= 500000000 {
2293                         return Err(ChannelError::Close("Remote provided CLTV expiry in seconds instead of block height".to_owned()));
2294                 }
2295
2296                 if self.channel_state & ChannelState::LocalShutdownSent as u32 != 0 {
2297                         if let PendingHTLCStatus::Forward(_) = pending_forward_status {
2298                                 panic!("ChannelManager shouldn't be trying to add a forwardable HTLC after we've started closing");
2299                         }
2300                 }
2301
2302                 // Now update local state:
2303                 self.next_counterparty_htlc_id += 1;
2304                 self.pending_inbound_htlcs.push(InboundHTLCOutput {
2305                         htlc_id: msg.htlc_id,
2306                         amount_msat: msg.amount_msat,
2307                         payment_hash: msg.payment_hash,
2308                         cltv_expiry: msg.cltv_expiry,
2309                         state: InboundHTLCState::RemoteAnnounced(pending_forward_status),
2310                 });
2311                 Ok(())
2312         }
2313
2314         /// Marks an outbound HTLC which we have received update_fail/fulfill/malformed
2315         #[inline]
2316         fn mark_outbound_htlc_removed(&mut self, htlc_id: u64, check_preimage: Option<PaymentHash>, fail_reason: Option<HTLCFailReason>) -> Result<&OutboundHTLCOutput, ChannelError> {
2317                 for htlc in self.pending_outbound_htlcs.iter_mut() {
2318                         if htlc.htlc_id == htlc_id {
2319                                 match check_preimage {
2320                                         None => {},
2321                                         Some(payment_hash) =>
2322                                                 if payment_hash != htlc.payment_hash {
2323                                                         return Err(ChannelError::Close(format!("Remote tried to fulfill HTLC ({}) with an incorrect preimage", htlc_id)));
2324                                                 }
2325                                 };
2326                                 match htlc.state {
2327                                         OutboundHTLCState::LocalAnnounced(_) =>
2328                                                 return Err(ChannelError::Close(format!("Remote tried to fulfill/fail HTLC ({}) before it had been committed", htlc_id))),
2329                                         OutboundHTLCState::Committed => {
2330                                                 htlc.state = OutboundHTLCState::RemoteRemoved(fail_reason);
2331                                         },
2332                                         OutboundHTLCState::AwaitingRemoteRevokeToRemove(_) | OutboundHTLCState::AwaitingRemovedRemoteRevoke(_) | OutboundHTLCState::RemoteRemoved(_) =>
2333                                                 return Err(ChannelError::Close(format!("Remote tried to fulfill/fail HTLC ({}) that they'd already fulfilled/failed", htlc_id))),
2334                                 }
2335                                 return Ok(htlc);
2336                         }
2337                 }
2338                 Err(ChannelError::Close("Remote tried to fulfill/fail an HTLC we couldn't find".to_owned()))
2339         }
2340
2341         pub fn update_fulfill_htlc(&mut self, msg: &msgs::UpdateFulfillHTLC) -> Result<(HTLCSource, u64), ChannelError> {
2342                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2343                         return Err(ChannelError::Close("Got fulfill HTLC message when channel was not in an operational state".to_owned()));
2344                 }
2345                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2346                         return Err(ChannelError::Close("Peer sent update_fulfill_htlc when we needed a channel_reestablish".to_owned()));
2347                 }
2348
2349                 let payment_hash = PaymentHash(Sha256::hash(&msg.payment_preimage.0[..]).into_inner());
2350                 self.mark_outbound_htlc_removed(msg.htlc_id, Some(payment_hash), None).map(|htlc| (htlc.source.clone(), htlc.amount_msat))
2351         }
2352
2353         pub fn update_fail_htlc(&mut self, msg: &msgs::UpdateFailHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> {
2354                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2355                         return Err(ChannelError::Close("Got fail HTLC message when channel was not in an operational state".to_owned()));
2356                 }
2357                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2358                         return Err(ChannelError::Close("Peer sent update_fail_htlc when we needed a channel_reestablish".to_owned()));
2359                 }
2360
2361                 self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason))?;
2362                 Ok(())
2363         }
2364
2365         pub fn update_fail_malformed_htlc(&mut self, msg: &msgs::UpdateFailMalformedHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> {
2366                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2367                         return Err(ChannelError::Close("Got fail malformed HTLC message when channel was not in an operational state".to_owned()));
2368                 }
2369                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2370                         return Err(ChannelError::Close("Peer sent update_fail_malformed_htlc when we needed a channel_reestablish".to_owned()));
2371                 }
2372
2373                 self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason))?;
2374                 Ok(())
2375         }
2376
2377         pub fn commitment_signed<L: Deref>(&mut self, msg: &msgs::CommitmentSigned, logger: &L) -> Result<(msgs::RevokeAndACK, Option<msgs::CommitmentSigned>, ChannelMonitorUpdate), (Option<ChannelMonitorUpdate>, ChannelError)>
2378                 where L::Target: Logger
2379         {
2380                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2381                         return Err((None, ChannelError::Close("Got commitment signed message when channel was not in an operational state".to_owned())));
2382                 }
2383                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2384                         return Err((None, ChannelError::Close("Peer sent commitment_signed when we needed a channel_reestablish".to_owned())));
2385                 }
2386                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() {
2387                         return Err((None, ChannelError::Close("Peer sent commitment_signed after we'd started exchanging closing_signeds".to_owned())));
2388                 }
2389
2390                 let funding_script = self.get_funding_redeemscript();
2391
2392                 let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number).map_err(|e| (None, e))?;
2393
2394                 let (num_htlcs, mut htlcs_cloned, commitment_tx, commitment_txid, feerate_per_kw) = {
2395                         let commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, false, logger);
2396                         let commitment_txid = {
2397                                 let trusted_tx = commitment_tx.0.trust();
2398                                 let bitcoin_tx = trusted_tx.built_transaction();
2399                                 let sighash = bitcoin_tx.get_sighash_all(&funding_script, self.channel_value_satoshis);
2400
2401                                 log_trace!(logger, "Checking commitment tx signature {} by key {} against tx {} (sighash {}) with redeemscript {} in channel {}",
2402                                         log_bytes!(msg.signature.serialize_compact()[..]),
2403                                         log_bytes!(self.counterparty_funding_pubkey().serialize()), encode::serialize_hex(&bitcoin_tx.transaction),
2404                                         log_bytes!(sighash[..]), encode::serialize_hex(&funding_script), log_bytes!(self.channel_id()));
2405                                 if let Err(_) = self.secp_ctx.verify(&sighash, &msg.signature, &self.counterparty_funding_pubkey()) {
2406                                         return Err((None, ChannelError::Close("Invalid commitment tx signature from peer".to_owned())));
2407                                 }
2408                                 bitcoin_tx.txid
2409                         };
2410                         let htlcs_cloned: Vec<_> = commitment_tx.3.iter().map(|htlc| (htlc.0.clone(), htlc.1.map(|h| h.clone()))).collect();
2411                         (commitment_tx.2, htlcs_cloned, commitment_tx.0, commitment_txid, commitment_tx.1)
2412                 };
2413
2414                 // If our counterparty updated the channel fee in this commitment transaction, check that
2415                 // they can actually afford the new fee now.
2416                 let update_fee = if let Some((_, update_state)) = self.pending_update_fee {
2417                         update_state == FeeUpdateState::RemoteAnnounced
2418                 } else { false };
2419                 if update_fee { debug_assert!(!self.is_outbound()); }
2420                 let total_fee = feerate_per_kw as u64 * (COMMITMENT_TX_BASE_WEIGHT + (num_htlcs as u64) * COMMITMENT_TX_WEIGHT_PER_HTLC) / 1000;
2421                 if update_fee {
2422                         let counterparty_reserve_we_require = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis);
2423                         if self.channel_value_satoshis - self.value_to_self_msat / 1000 < total_fee + counterparty_reserve_we_require {
2424                                 return Err((None, ChannelError::Close("Funding remote cannot afford proposed new fee".to_owned())));
2425                         }
2426                 }
2427                 #[cfg(any(test, feature = "fuzztarget"))]
2428                 {
2429                         if self.is_outbound() {
2430                                 let projected_commit_tx_info = self.next_local_commitment_tx_fee_info_cached.lock().unwrap().take();
2431                                 *self.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = None;
2432                                 if let Some(info) = projected_commit_tx_info {
2433                                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len()
2434                                                 + self.holding_cell_htlc_updates.len();
2435                                         if info.total_pending_htlcs == total_pending_htlcs
2436                                                 && info.next_holder_htlc_id == self.next_holder_htlc_id
2437                                                 && info.next_counterparty_htlc_id == self.next_counterparty_htlc_id
2438                                                 && info.feerate == self.feerate_per_kw {
2439                                                         assert_eq!(total_fee, info.fee / 1000);
2440                                                 }
2441                                 }
2442                         }
2443                 }
2444
2445                 if msg.htlc_signatures.len() != num_htlcs {
2446                         return Err((None, ChannelError::Close(format!("Got wrong number of HTLC signatures ({}) from remote. It must be {}", msg.htlc_signatures.len(), num_htlcs))));
2447                 }
2448
2449                 // TODO: Sadly, we pass HTLCs twice to ChannelMonitor: once via the HolderCommitmentTransaction and once via the update
2450                 let mut htlcs_and_sigs = Vec::with_capacity(htlcs_cloned.len());
2451                 for (idx, (htlc, source)) in htlcs_cloned.drain(..).enumerate() {
2452                         if let Some(_) = htlc.transaction_output_index {
2453                                 let htlc_tx = chan_utils::build_htlc_transaction(&commitment_txid, feerate_per_kw,
2454                                         self.get_counterparty_selected_contest_delay().unwrap(), &htlc,
2455                                         &keys.broadcaster_delayed_payment_key, &keys.revocation_key);
2456
2457                                 let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys);
2458                                 let htlc_sighash = hash_to_message!(&bip143::SigHashCache::new(&htlc_tx).signature_hash(0, &htlc_redeemscript, htlc.amount_msat / 1000, SigHashType::All)[..]);
2459                                 log_trace!(logger, "Checking HTLC tx signature {} by key {} against tx {} (sighash {}) with redeemscript {} in channel {}.",
2460                                         log_bytes!(msg.htlc_signatures[idx].serialize_compact()[..]), log_bytes!(keys.countersignatory_htlc_key.serialize()),
2461                                         encode::serialize_hex(&htlc_tx), log_bytes!(htlc_sighash[..]), encode::serialize_hex(&htlc_redeemscript), log_bytes!(self.channel_id()));
2462                                 if let Err(_) = self.secp_ctx.verify(&htlc_sighash, &msg.htlc_signatures[idx], &keys.countersignatory_htlc_key) {
2463                                         return Err((None, ChannelError::Close("Invalid HTLC tx signature from peer".to_owned())));
2464                                 }
2465                                 htlcs_and_sigs.push((htlc, Some(msg.htlc_signatures[idx]), source));
2466                         } else {
2467                                 htlcs_and_sigs.push((htlc, None, source));
2468                         }
2469                 }
2470
2471                 let holder_commitment_tx = HolderCommitmentTransaction::new(
2472                         commitment_tx,
2473                         msg.signature,
2474                         msg.htlc_signatures.clone(),
2475                         &self.get_holder_pubkeys().funding_pubkey,
2476                         self.counterparty_funding_pubkey()
2477                 );
2478
2479                 let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number - 1, &self.secp_ctx);
2480                 self.holder_signer.validate_holder_commitment(&holder_commitment_tx)
2481                         .map_err(|_| (None, ChannelError::Close("Failed to validate our commitment".to_owned())))?;
2482                 let per_commitment_secret = self.holder_signer.release_commitment_secret(self.cur_holder_commitment_transaction_number + 1);
2483
2484                 // Update state now that we've passed all the can-fail calls...
2485                 let mut need_commitment = false;
2486                 if let &mut Some((_, ref mut update_state)) = &mut self.pending_update_fee {
2487                         if *update_state == FeeUpdateState::RemoteAnnounced {
2488                                 *update_state = FeeUpdateState::AwaitingRemoteRevokeToAnnounce;
2489                                 need_commitment = true;
2490                         }
2491                 }
2492
2493                 self.latest_monitor_update_id += 1;
2494                 let mut monitor_update = ChannelMonitorUpdate {
2495                         update_id: self.latest_monitor_update_id,
2496                         updates: vec![ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo {
2497                                 commitment_tx: holder_commitment_tx,
2498                                 htlc_outputs: htlcs_and_sigs
2499                         }]
2500                 };
2501
2502                 for htlc in self.pending_inbound_htlcs.iter_mut() {
2503                         let new_forward = if let &InboundHTLCState::RemoteAnnounced(ref forward_info) = &htlc.state {
2504                                 Some(forward_info.clone())
2505                         } else { None };
2506                         if let Some(forward_info) = new_forward {
2507                                 log_trace!(logger, "Updating HTLC {} to AwaitingRemoteRevokeToAnnounce due to commitment_signed in channel {}.",
2508                                         log_bytes!(htlc.payment_hash.0), log_bytes!(self.channel_id));
2509                                 htlc.state = InboundHTLCState::AwaitingRemoteRevokeToAnnounce(forward_info);
2510                                 need_commitment = true;
2511                         }
2512                 }
2513                 for htlc in self.pending_outbound_htlcs.iter_mut() {
2514                         if let Some(fail_reason) = if let &mut OutboundHTLCState::RemoteRemoved(ref mut fail_reason) = &mut htlc.state {
2515                                 Some(fail_reason.take())
2516                         } else { None } {
2517                                 log_trace!(logger, "Updating HTLC {} to AwaitingRemoteRevokeToRemove due to commitment_signed in channel {}.",
2518                                         log_bytes!(htlc.payment_hash.0), log_bytes!(self.channel_id));
2519                                 htlc.state = OutboundHTLCState::AwaitingRemoteRevokeToRemove(fail_reason);
2520                                 need_commitment = true;
2521                         }
2522                 }
2523
2524                 self.cur_holder_commitment_transaction_number -= 1;
2525                 // Note that if we need_commitment & !AwaitingRemoteRevoke we'll call
2526                 // send_commitment_no_status_check() next which will reset this to RAAFirst.
2527                 self.resend_order = RAACommitmentOrder::CommitmentFirst;
2528
2529                 if (self.channel_state & ChannelState::MonitorUpdateFailed as u32) != 0 {
2530                         // In case we initially failed monitor updating without requiring a response, we need
2531                         // to make sure the RAA gets sent first.
2532                         self.monitor_pending_revoke_and_ack = true;
2533                         if need_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 {
2534                                 // If we were going to send a commitment_signed after the RAA, go ahead and do all
2535                                 // the corresponding HTLC status updates so that get_last_commitment_update
2536                                 // includes the right HTLCs.
2537                                 self.monitor_pending_commitment_signed = true;
2538                                 let (_, mut additional_update) = self.send_commitment_no_status_check(logger).map_err(|e| (None, e))?;
2539                                 // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2540                                 // strictly increasing by one, so decrement it here.
2541                                 self.latest_monitor_update_id = monitor_update.update_id;
2542                                 monitor_update.updates.append(&mut additional_update.updates);
2543                         }
2544                         log_debug!(logger, "Received valid commitment_signed from peer in channel {}, updated HTLC state but awaiting a monitor update resolution to reply.",
2545                                 log_bytes!(self.channel_id));
2546                         return Err((Some(monitor_update), ChannelError::Ignore("Previous monitor update failure prevented generation of RAA".to_owned())));
2547                 }
2548
2549                 let commitment_signed = if need_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 {
2550                         // If we're AwaitingRemoteRevoke we can't send a new commitment here, but that's ok -
2551                         // we'll send one right away when we get the revoke_and_ack when we
2552                         // free_holding_cell_htlcs().
2553                         let (msg, mut additional_update) = self.send_commitment_no_status_check(logger).map_err(|e| (None, e))?;
2554                         // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2555                         // strictly increasing by one, so decrement it here.
2556                         self.latest_monitor_update_id = monitor_update.update_id;
2557                         monitor_update.updates.append(&mut additional_update.updates);
2558                         Some(msg)
2559                 } else { None };
2560
2561                 log_debug!(logger, "Received valid commitment_signed from peer in channel {}, updating HTLC state and responding with{} a revoke_and_ack.",
2562                         log_bytes!(self.channel_id()), if commitment_signed.is_some() { " our own commitment_signed and" } else { "" });
2563
2564                 Ok((msgs::RevokeAndACK {
2565                         channel_id: self.channel_id,
2566                         per_commitment_secret,
2567                         next_per_commitment_point,
2568                 }, commitment_signed, monitor_update))
2569         }
2570
2571         /// Public version of the below, checking relevant preconditions first.
2572         /// If we're not in a state where freeing the holding cell makes sense, this is a no-op and
2573         /// returns `(None, Vec::new())`.
2574         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 {
2575                 if self.channel_state >= ChannelState::ChannelFunded as u32 &&
2576                    (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) == 0 {
2577                         self.free_holding_cell_htlcs(logger)
2578                 } else { Ok((None, Vec::new())) }
2579         }
2580
2581         /// Used to fulfill holding_cell_htlcs when we get a remote ack (or implicitly get it by them
2582         /// fulfilling or failing the last pending HTLC)
2583         fn free_holding_cell_htlcs<L: Deref>(&mut self, logger: &L) -> Result<(Option<(msgs::CommitmentUpdate, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>), ChannelError> where L::Target: Logger {
2584                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, 0);
2585                 if self.holding_cell_htlc_updates.len() != 0 || self.holding_cell_update_fee.is_some() {
2586                         log_trace!(logger, "Freeing holding cell with {} HTLC updates{} in channel {}", self.holding_cell_htlc_updates.len(),
2587                                 if self.holding_cell_update_fee.is_some() { " and a fee update" } else { "" }, log_bytes!(self.channel_id()));
2588
2589                         let mut monitor_update = ChannelMonitorUpdate {
2590                                 update_id: self.latest_monitor_update_id + 1, // We don't increment this yet!
2591                                 updates: Vec::new(),
2592                         };
2593
2594                         let mut htlc_updates = Vec::new();
2595                         mem::swap(&mut htlc_updates, &mut self.holding_cell_htlc_updates);
2596                         let mut update_add_htlcs = Vec::with_capacity(htlc_updates.len());
2597                         let mut update_fulfill_htlcs = Vec::with_capacity(htlc_updates.len());
2598                         let mut update_fail_htlcs = Vec::with_capacity(htlc_updates.len());
2599                         let mut htlcs_to_fail = Vec::new();
2600                         for htlc_update in htlc_updates.drain(..) {
2601                                 // Note that this *can* fail, though it should be due to rather-rare conditions on
2602                                 // fee races with adding too many outputs which push our total payments just over
2603                                 // the limit. In case it's less rare than I anticipate, we may want to revisit
2604                                 // handling this case better and maybe fulfilling some of the HTLCs while attempting
2605                                 // to rebalance channels.
2606                                 match &htlc_update {
2607                                         &HTLCUpdateAwaitingACK::AddHTLC {amount_msat, cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet, ..} => {
2608                                                 match self.send_htlc(amount_msat, *payment_hash, cltv_expiry, source.clone(), onion_routing_packet.clone()) {
2609                                                         Ok(update_add_msg_option) => update_add_htlcs.push(update_add_msg_option.unwrap()),
2610                                                         Err(e) => {
2611                                                                 match e {
2612                                                                         ChannelError::Ignore(ref msg) => {
2613                                                                                 log_info!(logger, "Failed to send HTLC with payment_hash {} due to {} in channel {}",
2614                                                                                         log_bytes!(payment_hash.0), msg, log_bytes!(self.channel_id()));
2615                                                                                 // If we fail to send here, then this HTLC should
2616                                                                                 // be failed backwards. Failing to send here
2617                                                                                 // indicates that this HTLC may keep being put back
2618                                                                                 // into the holding cell without ever being
2619                                                                                 // successfully forwarded/failed/fulfilled, causing
2620                                                                                 // our counterparty to eventually close on us.
2621                                                                                 htlcs_to_fail.push((source.clone(), *payment_hash));
2622                                                                         },
2623                                                                         _ => {
2624                                                                                 panic!("Got a non-IgnoreError action trying to send holding cell HTLC");
2625                                                                         },
2626                                                                 }
2627                                                         }
2628                                                 }
2629                                         },
2630                                         &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, htlc_id, .. } => {
2631                                                 // If an HTLC claim was previously added to the holding cell (via
2632                                                 // `get_update_fulfill_htlc`, then generating the claim message itself must
2633                                                 // not fail - any in between attempts to claim the HTLC will have resulted
2634                                                 // in it hitting the holding cell again and we cannot change the state of a
2635                                                 // holding cell HTLC from fulfill to anything else.
2636                                                 let (update_fulfill_msg_option, mut additional_monitor_update) =
2637                                                         if let UpdateFulfillFetch::NewClaim { msg, monitor_update, .. } = self.get_update_fulfill_htlc(htlc_id, *payment_preimage, logger) {
2638                                                                 (msg, monitor_update)
2639                                                         } else { unreachable!() };
2640                                                 update_fulfill_htlcs.push(update_fulfill_msg_option.unwrap());
2641                                                 monitor_update.updates.append(&mut additional_monitor_update.updates);
2642                                         },
2643                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, ref err_packet } => {
2644                                                 match self.get_update_fail_htlc(htlc_id, err_packet.clone(), logger) {
2645                                                         Ok(update_fail_msg_option) => {
2646                                                                 // If an HTLC failure was previously added to the holding cell (via
2647                                                                 // `get_update_fail_htlc`) then generating the fail message itself
2648                                                                 // must not fail - we should never end up in a state where we
2649                                                                 // double-fail an HTLC or fail-then-claim an HTLC as it indicates
2650                                                                 // we didn't wait for a full revocation before failing.
2651                                                                 update_fail_htlcs.push(update_fail_msg_option.unwrap())
2652                                                         },
2653                                                         Err(e) => {
2654                                                                 if let ChannelError::Ignore(_) = e {}
2655                                                                 else {
2656                                                                         panic!("Got a non-IgnoreError action trying to fail holding cell HTLC");
2657                                                                 }
2658                                                         }
2659                                                 }
2660                                         },
2661                                 }
2662                         }
2663                         if update_add_htlcs.is_empty() && update_fulfill_htlcs.is_empty() && update_fail_htlcs.is_empty() && self.holding_cell_update_fee.is_none() {
2664                                 return Ok((None, htlcs_to_fail));
2665                         }
2666                         let update_fee = if let Some(feerate) = self.holding_cell_update_fee.take() {
2667                                 assert!(self.is_outbound());
2668                                 self.pending_update_fee = Some((feerate, FeeUpdateState::Outbound));
2669                                 Some(msgs::UpdateFee {
2670                                         channel_id: self.channel_id,
2671                                         feerate_per_kw: feerate as u32,
2672                                 })
2673                         } else {
2674                                 None
2675                         };
2676
2677                         let (commitment_signed, mut additional_update) = self.send_commitment_no_status_check(logger)?;
2678                         // send_commitment_no_status_check and get_update_fulfill_htlc may bump latest_monitor_id
2679                         // but we want them to be strictly increasing by one, so reset it here.
2680                         self.latest_monitor_update_id = monitor_update.update_id;
2681                         monitor_update.updates.append(&mut additional_update.updates);
2682
2683                         log_debug!(logger, "Freeing holding cell in channel {} resulted in {}{} HTLCs added, {} HTLCs fulfilled, and {} HTLCs failed.",
2684                                 log_bytes!(self.channel_id()), if update_fee.is_some() { "a fee update, " } else { "" },
2685                                 update_add_htlcs.len(), update_fulfill_htlcs.len(), update_fail_htlcs.len());
2686
2687                         Ok((Some((msgs::CommitmentUpdate {
2688                                 update_add_htlcs,
2689                                 update_fulfill_htlcs,
2690                                 update_fail_htlcs,
2691                                 update_fail_malformed_htlcs: Vec::new(),
2692                                 update_fee,
2693                                 commitment_signed,
2694                         }, monitor_update)), htlcs_to_fail))
2695                 } else {
2696                         Ok((None, Vec::new()))
2697                 }
2698         }
2699
2700         /// Handles receiving a remote's revoke_and_ack. Note that we may return a new
2701         /// commitment_signed message here in case we had pending outbound HTLCs to add which were
2702         /// waiting on this revoke_and_ack. The generation of this new commitment_signed may also fail,
2703         /// generating an appropriate error *after* the channel state has been updated based on the
2704         /// revoke_and_ack message.
2705         pub fn revoke_and_ack<L: Deref>(&mut self, msg: &msgs::RevokeAndACK, logger: &L) -> Result<(Option<msgs::CommitmentUpdate>, Vec<(PendingHTLCInfo, u64)>, Vec<(HTLCSource, PaymentHash, HTLCFailReason)>, ChannelMonitorUpdate, Vec<(HTLCSource, PaymentHash)>), ChannelError>
2706                 where L::Target: Logger,
2707         {
2708                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2709                         return Err(ChannelError::Close("Got revoke/ACK message when channel was not in an operational state".to_owned()));
2710                 }
2711                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2712                         return Err(ChannelError::Close("Peer sent revoke_and_ack when we needed a channel_reestablish".to_owned()));
2713                 }
2714                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() {
2715                         return Err(ChannelError::Close("Peer sent revoke_and_ack after we'd started exchanging closing_signeds".to_owned()));
2716                 }
2717
2718                 let secret = secp_check!(SecretKey::from_slice(&msg.per_commitment_secret), "Peer provided an invalid per_commitment_secret".to_owned());
2719
2720                 if let Some(counterparty_prev_commitment_point) = self.counterparty_prev_commitment_point {
2721                         if PublicKey::from_secret_key(&self.secp_ctx, &secret) != counterparty_prev_commitment_point {
2722                                 return Err(ChannelError::Close("Got a revoke commitment secret which didn't correspond to their current pubkey".to_owned()));
2723                         }
2724                 }
2725
2726                 if self.channel_state & ChannelState::AwaitingRemoteRevoke as u32 == 0 {
2727                         // Our counterparty seems to have burned their coins to us (by revoking a state when we
2728                         // haven't given them a new commitment transaction to broadcast). We should probably
2729                         // take advantage of this by updating our channel monitor, sending them an error, and
2730                         // waiting for them to broadcast their latest (now-revoked claim). But, that would be a
2731                         // lot of work, and there's some chance this is all a misunderstanding anyway.
2732                         // We have to do *something*, though, since our signer may get mad at us for otherwise
2733                         // jumping a remote commitment number, so best to just force-close and move on.
2734                         return Err(ChannelError::Close("Received an unexpected revoke_and_ack".to_owned()));
2735                 }
2736
2737                 #[cfg(any(test, feature = "fuzztarget"))]
2738                 {
2739                         *self.next_local_commitment_tx_fee_info_cached.lock().unwrap() = None;
2740                         *self.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = None;
2741                 }
2742
2743                 self.holder_signer.validate_counterparty_revocation(
2744                         self.cur_counterparty_commitment_transaction_number + 1,
2745                         &secret
2746                 ).map_err(|_| ChannelError::Close("Failed to validate revocation from peer".to_owned()))?;
2747
2748                 self.commitment_secrets.provide_secret(self.cur_counterparty_commitment_transaction_number + 1, msg.per_commitment_secret)
2749                         .map_err(|_| ChannelError::Close("Previous secrets did not match new one".to_owned()))?;
2750                 self.latest_monitor_update_id += 1;
2751                 let mut monitor_update = ChannelMonitorUpdate {
2752                         update_id: self.latest_monitor_update_id,
2753                         updates: vec![ChannelMonitorUpdateStep::CommitmentSecret {
2754                                 idx: self.cur_counterparty_commitment_transaction_number + 1,
2755                                 secret: msg.per_commitment_secret,
2756                         }],
2757                 };
2758
2759                 // Update state now that we've passed all the can-fail calls...
2760                 // (note that we may still fail to generate the new commitment_signed message, but that's
2761                 // OK, we step the channel here and *then* if the new generation fails we can fail the
2762                 // channel based on that, but stepping stuff here should be safe either way.
2763                 self.channel_state &= !(ChannelState::AwaitingRemoteRevoke as u32);
2764                 self.counterparty_prev_commitment_point = self.counterparty_cur_commitment_point;
2765                 self.counterparty_cur_commitment_point = Some(msg.next_per_commitment_point);
2766                 self.cur_counterparty_commitment_transaction_number -= 1;
2767
2768                 log_trace!(logger, "Updating HTLCs on receipt of RAA in channel {}...", log_bytes!(self.channel_id()));
2769                 let mut to_forward_infos = Vec::new();
2770                 let mut revoked_htlcs = Vec::new();
2771                 let mut update_fail_htlcs = Vec::new();
2772                 let mut update_fail_malformed_htlcs = Vec::new();
2773                 let mut require_commitment = false;
2774                 let mut value_to_self_msat_diff: i64 = 0;
2775
2776                 {
2777                         // Take references explicitly so that we can hold multiple references to self.
2778                         let pending_inbound_htlcs: &mut Vec<_> = &mut self.pending_inbound_htlcs;
2779                         let pending_outbound_htlcs: &mut Vec<_> = &mut self.pending_outbound_htlcs;
2780
2781                         // We really shouldnt have two passes here, but retain gives a non-mutable ref (Rust bug)
2782                         pending_inbound_htlcs.retain(|htlc| {
2783                                 if let &InboundHTLCState::LocalRemoved(ref reason) = &htlc.state {
2784                                         log_trace!(logger, " ...removing inbound LocalRemoved {}", log_bytes!(htlc.payment_hash.0));
2785                                         if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
2786                                                 value_to_self_msat_diff += htlc.amount_msat as i64;
2787                                         }
2788                                         false
2789                                 } else { true }
2790                         });
2791                         pending_outbound_htlcs.retain(|htlc| {
2792                                 if let &OutboundHTLCState::AwaitingRemovedRemoteRevoke(ref fail_reason) = &htlc.state {
2793                                         log_trace!(logger, " ...removing outbound AwaitingRemovedRemoteRevoke {}", log_bytes!(htlc.payment_hash.0));
2794                                         if let Some(reason) = fail_reason.clone() { // We really want take() here, but, again, non-mut ref :(
2795                                                 revoked_htlcs.push((htlc.source.clone(), htlc.payment_hash, reason));
2796                                         } else {
2797                                                 // They fulfilled, so we sent them money
2798                                                 value_to_self_msat_diff -= htlc.amount_msat as i64;
2799                                         }
2800                                         false
2801                                 } else { true }
2802                         });
2803                         for htlc in pending_inbound_htlcs.iter_mut() {
2804                                 let swap = if let &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_) = &htlc.state {
2805                                         true
2806                                 } else if let &InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) = &htlc.state {
2807                                         true
2808                                 } else { false };
2809                                 if swap {
2810                                         let mut state = InboundHTLCState::Committed;
2811                                         mem::swap(&mut state, &mut htlc.state);
2812
2813                                         if let InboundHTLCState::AwaitingRemoteRevokeToAnnounce(forward_info) = state {
2814                                                 log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce {} to AwaitingAnnouncedRemoteRevoke", log_bytes!(htlc.payment_hash.0));
2815                                                 htlc.state = InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info);
2816                                                 require_commitment = true;
2817                                         } else if let InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info) = state {
2818                                                 match forward_info {
2819                                                         PendingHTLCStatus::Fail(fail_msg) => {
2820                                                                 log_trace!(logger, " ...promoting inbound AwaitingAnnouncedRemoteRevoke {} to LocalRemoved due to PendingHTLCStatus indicating failure", log_bytes!(htlc.payment_hash.0));
2821                                                                 require_commitment = true;
2822                                                                 match fail_msg {
2823                                                                         HTLCFailureMsg::Relay(msg) => {
2824                                                                                 htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(msg.reason.clone()));
2825                                                                                 update_fail_htlcs.push(msg)
2826                                                                         },
2827                                                                         HTLCFailureMsg::Malformed(msg) => {
2828                                                                                 htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailMalformed((msg.sha256_of_onion, msg.failure_code)));
2829                                                                                 update_fail_malformed_htlcs.push(msg)
2830                                                                         },
2831                                                                 }
2832                                                         },
2833                                                         PendingHTLCStatus::Forward(forward_info) => {
2834                                                                 log_trace!(logger, " ...promoting inbound AwaitingAnnouncedRemoteRevoke {} to Committed", log_bytes!(htlc.payment_hash.0));
2835                                                                 to_forward_infos.push((forward_info, htlc.htlc_id));
2836                                                                 htlc.state = InboundHTLCState::Committed;
2837                                                         }
2838                                                 }
2839                                         }
2840                                 }
2841                         }
2842                         for htlc in pending_outbound_htlcs.iter_mut() {
2843                                 if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
2844                                         log_trace!(logger, " ...promoting outbound LocalAnnounced {} to Committed", log_bytes!(htlc.payment_hash.0));
2845                                         htlc.state = OutboundHTLCState::Committed;
2846                                 }
2847                                 if let Some(fail_reason) = if let &mut OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref mut fail_reason) = &mut htlc.state {
2848                                         Some(fail_reason.take())
2849                                 } else { None } {
2850                                         log_trace!(logger, " ...promoting outbound AwaitingRemoteRevokeToRemove {} to AwaitingRemovedRemoteRevoke", log_bytes!(htlc.payment_hash.0));
2851                                         htlc.state = OutboundHTLCState::AwaitingRemovedRemoteRevoke(fail_reason);
2852                                         require_commitment = true;
2853                                 }
2854                         }
2855                 }
2856                 self.value_to_self_msat = (self.value_to_self_msat as i64 + value_to_self_msat_diff) as u64;
2857
2858                 if let Some((feerate, update_state)) = self.pending_update_fee {
2859                         match update_state {
2860                                 FeeUpdateState::Outbound => {
2861                                         debug_assert!(self.is_outbound());
2862                                         log_trace!(logger, " ...promoting outbound fee update {} to Committed", feerate);
2863                                         self.feerate_per_kw = feerate;
2864                                         self.pending_update_fee = None;
2865                                 },
2866                                 FeeUpdateState::RemoteAnnounced => { debug_assert!(!self.is_outbound()); },
2867                                 FeeUpdateState::AwaitingRemoteRevokeToAnnounce => {
2868                                         debug_assert!(!self.is_outbound());
2869                                         log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce fee update {} to Committed", feerate);
2870                                         require_commitment = true;
2871                                         self.feerate_per_kw = feerate;
2872                                         self.pending_update_fee = None;
2873                                 },
2874                         }
2875                 }
2876
2877                 if (self.channel_state & ChannelState::MonitorUpdateFailed as u32) == ChannelState::MonitorUpdateFailed as u32 {
2878                         // We can't actually generate a new commitment transaction (incl by freeing holding
2879                         // cells) while we can't update the monitor, so we just return what we have.
2880                         if require_commitment {
2881                                 self.monitor_pending_commitment_signed = true;
2882                                 // When the monitor updating is restored we'll call get_last_commitment_update(),
2883                                 // which does not update state, but we're definitely now awaiting a remote revoke
2884                                 // before we can step forward any more, so set it here.
2885                                 let (_, mut additional_update) = self.send_commitment_no_status_check(logger)?;
2886                                 // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2887                                 // strictly increasing by one, so decrement it here.
2888                                 self.latest_monitor_update_id = monitor_update.update_id;
2889                                 monitor_update.updates.append(&mut additional_update.updates);
2890                         }
2891                         self.monitor_pending_forwards.append(&mut to_forward_infos);
2892                         self.monitor_pending_failures.append(&mut revoked_htlcs);
2893                         log_debug!(logger, "Received a valid revoke_and_ack for channel {} but awaiting a monitor update resolution to reply.", log_bytes!(self.channel_id()));
2894                         return Ok((None, Vec::new(), Vec::new(), monitor_update, Vec::new()))
2895                 }
2896
2897                 match self.free_holding_cell_htlcs(logger)? {
2898                         (Some((mut commitment_update, mut additional_update)), htlcs_to_fail) => {
2899                                 commitment_update.update_fail_htlcs.reserve(update_fail_htlcs.len());
2900                                 for fail_msg in update_fail_htlcs.drain(..) {
2901                                         commitment_update.update_fail_htlcs.push(fail_msg);
2902                                 }
2903                                 commitment_update.update_fail_malformed_htlcs.reserve(update_fail_malformed_htlcs.len());
2904                                 for fail_msg in update_fail_malformed_htlcs.drain(..) {
2905                                         commitment_update.update_fail_malformed_htlcs.push(fail_msg);
2906                                 }
2907
2908                                 // free_holding_cell_htlcs may bump latest_monitor_id multiple times but we want them to be
2909                                 // strictly increasing by one, so decrement it here.
2910                                 self.latest_monitor_update_id = monitor_update.update_id;
2911                                 monitor_update.updates.append(&mut additional_update.updates);
2912
2913                                 Ok((Some(commitment_update), to_forward_infos, revoked_htlcs, monitor_update, htlcs_to_fail))
2914                         },
2915                         (None, htlcs_to_fail) => {
2916                                 if require_commitment {
2917                                         let (commitment_signed, mut additional_update) = self.send_commitment_no_status_check(logger)?;
2918
2919                                         // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2920                                         // strictly increasing by one, so decrement it here.
2921                                         self.latest_monitor_update_id = monitor_update.update_id;
2922                                         monitor_update.updates.append(&mut additional_update.updates);
2923
2924                                         log_debug!(logger, "Received a valid revoke_and_ack for channel {}. Responding with a commitment update with {} HTLCs failed.",
2925                                                 log_bytes!(self.channel_id()), update_fail_htlcs.len() + update_fail_malformed_htlcs.len());
2926                                         Ok((Some(msgs::CommitmentUpdate {
2927                                                 update_add_htlcs: Vec::new(),
2928                                                 update_fulfill_htlcs: Vec::new(),
2929                                                 update_fail_htlcs,
2930                                                 update_fail_malformed_htlcs,
2931                                                 update_fee: None,
2932                                                 commitment_signed
2933                                         }), to_forward_infos, revoked_htlcs, monitor_update, htlcs_to_fail))
2934                                 } else {
2935                                         log_debug!(logger, "Received a valid revoke_and_ack for channel {} with no reply necessary.", log_bytes!(self.channel_id()));
2936                                         Ok((None, to_forward_infos, revoked_htlcs, monitor_update, htlcs_to_fail))
2937                                 }
2938                         }
2939                 }
2940         }
2941
2942         /// Adds a pending update to this channel. See the doc for send_htlc for
2943         /// further details on the optionness of the return value.
2944         /// You MUST call send_commitment prior to any other calls on this Channel
2945         fn send_update_fee(&mut self, feerate_per_kw: u32) -> Option<msgs::UpdateFee> {
2946                 if !self.is_outbound() {
2947                         panic!("Cannot send fee from inbound channel");
2948                 }
2949                 if !self.is_usable() {
2950                         panic!("Cannot update fee until channel is fully established and we haven't started shutting down");
2951                 }
2952                 if !self.is_live() {
2953                         panic!("Cannot update fee while peer is disconnected/we're awaiting a monitor update (ChannelManager should have caught this)");
2954                 }
2955
2956                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
2957                         self.holding_cell_update_fee = Some(feerate_per_kw);
2958                         return None;
2959                 }
2960
2961                 debug_assert!(self.pending_update_fee.is_none());
2962                 self.pending_update_fee = Some((feerate_per_kw, FeeUpdateState::Outbound));
2963
2964                 Some(msgs::UpdateFee {
2965                         channel_id: self.channel_id,
2966                         feerate_per_kw,
2967                 })
2968         }
2969
2970         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 {
2971                 match self.send_update_fee(feerate_per_kw) {
2972                         Some(update_fee) => {
2973                                 let (commitment_signed, monitor_update) = self.send_commitment_no_status_check(logger)?;
2974                                 Ok(Some((update_fee, commitment_signed, monitor_update)))
2975                         },
2976                         None => Ok(None)
2977                 }
2978         }
2979
2980         /// Removes any uncommitted inbound HTLCs and resets the state of uncommitted outbound HTLC
2981         /// updates, to be used on peer disconnection. After this, update_*_htlc messages need to be
2982         /// resent.
2983         /// No further message handling calls may be made until a channel_reestablish dance has
2984         /// completed.
2985         pub fn remove_uncommitted_htlcs_and_mark_paused<L: Deref>(&mut self, logger: &L)  where L::Target: Logger {
2986                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
2987                 if self.channel_state < ChannelState::FundingSent as u32 {
2988                         self.channel_state = ChannelState::ShutdownComplete as u32;
2989                         return;
2990                 }
2991                 // Upon reconnect we have to start the closing_signed dance over, but shutdown messages
2992                 // will be retransmitted.
2993                 self.last_sent_closing_fee = None;
2994                 self.pending_counterparty_closing_signed = None;
2995                 self.closing_fee_limits = None;
2996
2997                 let mut inbound_drop_count = 0;
2998                 self.pending_inbound_htlcs.retain(|htlc| {
2999                         match htlc.state {
3000                                 InboundHTLCState::RemoteAnnounced(_) => {
3001                                         // They sent us an update_add_htlc but we never got the commitment_signed.
3002                                         // We'll tell them what commitment_signed we're expecting next and they'll drop
3003                                         // this HTLC accordingly
3004                                         inbound_drop_count += 1;
3005                                         false
3006                                 },
3007                                 InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_)|InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) => {
3008                                         // We received a commitment_signed updating this HTLC and (at least hopefully)
3009                                         // sent a revoke_and_ack (which we can re-transmit) and have heard nothing
3010                                         // in response to it yet, so don't touch it.
3011                                         true
3012                                 },
3013                                 InboundHTLCState::Committed => true,
3014                                 InboundHTLCState::LocalRemoved(_) => {
3015                                         // We (hopefully) sent a commitment_signed updating this HTLC (which we can
3016                                         // re-transmit if needed) and they may have even sent a revoke_and_ack back
3017                                         // (that we missed). Keep this around for now and if they tell us they missed
3018                                         // the commitment_signed we can re-transmit the update then.
3019                                         true
3020                                 },
3021                         }
3022                 });
3023                 self.next_counterparty_htlc_id -= inbound_drop_count;
3024
3025                 if let Some((_, update_state)) = self.pending_update_fee {
3026                         if update_state == FeeUpdateState::RemoteAnnounced {
3027                                 debug_assert!(!self.is_outbound());
3028                                 self.pending_update_fee = None;
3029                         }
3030                 }
3031
3032                 for htlc in self.pending_outbound_htlcs.iter_mut() {
3033                         if let OutboundHTLCState::RemoteRemoved(_) = htlc.state {
3034                                 // They sent us an update to remove this but haven't yet sent the corresponding
3035                                 // commitment_signed, we need to move it back to Committed and they can re-send
3036                                 // the update upon reconnection.
3037                                 htlc.state = OutboundHTLCState::Committed;
3038                         }
3039                 }
3040
3041                 self.channel_state |= ChannelState::PeerDisconnected as u32;
3042                 log_trace!(logger, "Peer disconnection resulted in {} remote-announced HTLC drops on channel {}", inbound_drop_count, log_bytes!(self.channel_id()));
3043         }
3044
3045         /// Indicates that a ChannelMonitor update failed to be stored by the client and further
3046         /// updates are partially paused.
3047         /// This must be called immediately after the call which generated the ChannelMonitor update
3048         /// which failed. The messages which were generated from that call which generated the
3049         /// monitor update failure must *not* have been sent to the remote end, and must instead
3050         /// have been dropped. They will be regenerated when monitor_updating_restored is called.
3051         pub fn monitor_update_failed(&mut self, resend_raa: bool, resend_commitment: bool, mut pending_forwards: Vec<(PendingHTLCInfo, u64)>, mut pending_fails: Vec<(HTLCSource, PaymentHash, HTLCFailReason)>) {
3052                 self.monitor_pending_revoke_and_ack |= resend_raa;
3053                 self.monitor_pending_commitment_signed |= resend_commitment;
3054                 self.monitor_pending_forwards.append(&mut pending_forwards);
3055                 self.monitor_pending_failures.append(&mut pending_fails);
3056                 self.channel_state |= ChannelState::MonitorUpdateFailed as u32;
3057         }
3058
3059         /// Indicates that the latest ChannelMonitor update has been committed by the client
3060         /// successfully and we should restore normal operation. Returns messages which should be sent
3061         /// to the remote side.
3062         pub fn monitor_updating_restored<L: Deref>(&mut self, logger: &L) -> (Option<msgs::RevokeAndACK>, Option<msgs::CommitmentUpdate>, RAACommitmentOrder, Vec<(PendingHTLCInfo, u64)>, Vec<(HTLCSource, PaymentHash, HTLCFailReason)>, Option<Transaction>, Option<msgs::FundingLocked>) where L::Target: Logger {
3063                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, ChannelState::MonitorUpdateFailed as u32);
3064                 self.channel_state &= !(ChannelState::MonitorUpdateFailed as u32);
3065
3066                 let funding_broadcastable = if self.channel_state & (ChannelState::FundingSent as u32) != 0 && self.is_outbound() {
3067                         self.funding_transaction.take()
3068                 } else { None };
3069
3070                 // We will never broadcast the funding transaction when we're in MonitorUpdateFailed (and
3071                 // we assume the user never directly broadcasts the funding transaction and waits for us to
3072                 // do it). Thus, we can only ever hit monitor_pending_funding_locked when we're an inbound
3073                 // channel which failed to persist the monitor on funding_created, and we got the funding
3074                 // transaction confirmed before the monitor was persisted.
3075                 let funding_locked = if self.monitor_pending_funding_locked {
3076                         assert!(!self.is_outbound(), "Funding transaction broadcast by the local client before it should have - LDK didn't do it!");
3077                         self.monitor_pending_funding_locked = false;
3078                         let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3079                         Some(msgs::FundingLocked {
3080                                 channel_id: self.channel_id(),
3081                                 next_per_commitment_point,
3082                         })
3083                 } else { None };
3084
3085                 let mut forwards = Vec::new();
3086                 mem::swap(&mut forwards, &mut self.monitor_pending_forwards);
3087                 let mut failures = Vec::new();
3088                 mem::swap(&mut failures, &mut self.monitor_pending_failures);
3089
3090                 if self.channel_state & (ChannelState::PeerDisconnected as u32) != 0 {
3091                         self.monitor_pending_revoke_and_ack = false;
3092                         self.monitor_pending_commitment_signed = false;
3093                         return (None, None, RAACommitmentOrder::RevokeAndACKFirst, forwards, failures, funding_broadcastable, funding_locked);
3094                 }
3095
3096                 let raa = if self.monitor_pending_revoke_and_ack {
3097                         Some(self.get_last_revoke_and_ack())
3098                 } else { None };
3099                 let commitment_update = if self.monitor_pending_commitment_signed {
3100                         Some(self.get_last_commitment_update(logger))
3101                 } else { None };
3102
3103                 self.monitor_pending_revoke_and_ack = false;
3104                 self.monitor_pending_commitment_signed = false;
3105                 let order = self.resend_order.clone();
3106                 log_debug!(logger, "Restored monitor updating in channel {} resulting in {}{} commitment update and {} RAA, with {} first",
3107                         log_bytes!(self.channel_id()), if funding_broadcastable.is_some() { "a funding broadcastable, " } else { "" },
3108                         if commitment_update.is_some() { "a" } else { "no" }, if raa.is_some() { "an" } else { "no" },
3109                         match order { RAACommitmentOrder::CommitmentFirst => "commitment", RAACommitmentOrder::RevokeAndACKFirst => "RAA"});
3110                 (raa, commitment_update, order, forwards, failures, funding_broadcastable, funding_locked)
3111         }
3112
3113         pub fn update_fee<F: Deref>(&mut self, fee_estimator: &F, msg: &msgs::UpdateFee) -> Result<(), ChannelError>
3114                 where F::Target: FeeEstimator
3115         {
3116                 if self.is_outbound() {
3117                         return Err(ChannelError::Close("Non-funding remote tried to update channel fee".to_owned()));
3118                 }
3119                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
3120                         return Err(ChannelError::Close("Peer sent update_fee when we needed a channel_reestablish".to_owned()));
3121                 }
3122                 Channel::<Signer>::check_remote_fee(fee_estimator, msg.feerate_per_kw)?;
3123                 let feerate_over_dust_buffer = msg.feerate_per_kw > self.get_dust_buffer_feerate();
3124
3125                 self.pending_update_fee = Some((msg.feerate_per_kw, FeeUpdateState::RemoteAnnounced));
3126                 self.update_time_counter += 1;
3127                 // If the feerate has increased over the previous dust buffer (note that
3128                 // `get_dust_buffer_feerate` considers the `pending_update_fee` status), check that we
3129                 // won't be pushed over our dust exposure limit by the feerate increase.
3130                 if feerate_over_dust_buffer {
3131                         let inbound_stats = self.get_inbound_pending_htlc_stats();
3132                         let outbound_stats = self.get_outbound_pending_htlc_stats();
3133                         let holder_tx_dust_exposure = inbound_stats.on_holder_tx_dust_exposure_msat + outbound_stats.on_holder_tx_dust_exposure_msat;
3134                         let counterparty_tx_dust_exposure = inbound_stats.on_counterparty_tx_dust_exposure_msat + outbound_stats.on_counterparty_tx_dust_exposure_msat;
3135                         if holder_tx_dust_exposure > self.get_max_dust_htlc_exposure_msat() {
3136                                 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)",
3137                                         msg.feerate_per_kw, holder_tx_dust_exposure)));
3138                         }
3139                         if counterparty_tx_dust_exposure > self.get_max_dust_htlc_exposure_msat() {
3140                                 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)",
3141                                         msg.feerate_per_kw, counterparty_tx_dust_exposure)));
3142                         }
3143                 }
3144                 Ok(())
3145         }
3146
3147         fn get_last_revoke_and_ack(&self) -> msgs::RevokeAndACK {
3148                 let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3149                 let per_commitment_secret = self.holder_signer.release_commitment_secret(self.cur_holder_commitment_transaction_number + 2);
3150                 msgs::RevokeAndACK {
3151                         channel_id: self.channel_id,
3152                         per_commitment_secret,
3153                         next_per_commitment_point,
3154                 }
3155         }
3156
3157         fn get_last_commitment_update<L: Deref>(&self, logger: &L) -> msgs::CommitmentUpdate where L::Target: Logger {
3158                 let mut update_add_htlcs = Vec::new();
3159                 let mut update_fulfill_htlcs = Vec::new();
3160                 let mut update_fail_htlcs = Vec::new();
3161                 let mut update_fail_malformed_htlcs = Vec::new();
3162
3163                 for htlc in self.pending_outbound_htlcs.iter() {
3164                         if let &OutboundHTLCState::LocalAnnounced(ref onion_packet) = &htlc.state {
3165                                 update_add_htlcs.push(msgs::UpdateAddHTLC {
3166                                         channel_id: self.channel_id(),
3167                                         htlc_id: htlc.htlc_id,
3168                                         amount_msat: htlc.amount_msat,
3169                                         payment_hash: htlc.payment_hash,
3170                                         cltv_expiry: htlc.cltv_expiry,
3171                                         onion_routing_packet: (**onion_packet).clone(),
3172                                 });
3173                         }
3174                 }
3175
3176                 for htlc in self.pending_inbound_htlcs.iter() {
3177                         if let &InboundHTLCState::LocalRemoved(ref reason) = &htlc.state {
3178                                 match reason {
3179                                         &InboundHTLCRemovalReason::FailRelay(ref err_packet) => {
3180                                                 update_fail_htlcs.push(msgs::UpdateFailHTLC {
3181                                                         channel_id: self.channel_id(),
3182                                                         htlc_id: htlc.htlc_id,
3183                                                         reason: err_packet.clone()
3184                                                 });
3185                                         },
3186                                         &InboundHTLCRemovalReason::FailMalformed((ref sha256_of_onion, ref failure_code)) => {
3187                                                 update_fail_malformed_htlcs.push(msgs::UpdateFailMalformedHTLC {
3188                                                         channel_id: self.channel_id(),
3189                                                         htlc_id: htlc.htlc_id,
3190                                                         sha256_of_onion: sha256_of_onion.clone(),
3191                                                         failure_code: failure_code.clone(),
3192                                                 });
3193                                         },
3194                                         &InboundHTLCRemovalReason::Fulfill(ref payment_preimage) => {
3195                                                 update_fulfill_htlcs.push(msgs::UpdateFulfillHTLC {
3196                                                         channel_id: self.channel_id(),
3197                                                         htlc_id: htlc.htlc_id,
3198                                                         payment_preimage: payment_preimage.clone(),
3199                                                 });
3200                                         },
3201                                 }
3202                         }
3203                 }
3204
3205                 let update_fee = if self.is_outbound() && self.pending_update_fee.is_some() {
3206                         Some(msgs::UpdateFee {
3207                                 channel_id: self.channel_id(),
3208                                 feerate_per_kw: self.pending_update_fee.unwrap().0,
3209                         })
3210                 } else { None };
3211
3212                 log_trace!(logger, "Regenerated latest commitment update in channel {} with{} {} update_adds, {} update_fulfills, {} update_fails, and {} update_fail_malformeds",
3213                                 log_bytes!(self.channel_id()), if update_fee.is_some() { " update_fee," } else { "" },
3214                                 update_add_htlcs.len(), update_fulfill_htlcs.len(), update_fail_htlcs.len(), update_fail_malformed_htlcs.len());
3215                 msgs::CommitmentUpdate {
3216                         update_add_htlcs, update_fulfill_htlcs, update_fail_htlcs, update_fail_malformed_htlcs, update_fee,
3217                         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,
3218                 }
3219         }
3220
3221         /// May panic if some calls other than message-handling calls (which will all Err immediately)
3222         /// have been called between remove_uncommitted_htlcs_and_mark_paused and this call.
3223         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 {
3224                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == 0 {
3225                         // While BOLT 2 doesn't indicate explicitly we should error this channel here, it
3226                         // almost certainly indicates we are going to end up out-of-sync in some way, so we
3227                         // just close here instead of trying to recover.
3228                         return Err(ChannelError::Close("Peer sent a loose channel_reestablish not after reconnect".to_owned()));
3229                 }
3230
3231                 if msg.next_local_commitment_number >= INITIAL_COMMITMENT_NUMBER || msg.next_remote_commitment_number >= INITIAL_COMMITMENT_NUMBER ||
3232                         msg.next_local_commitment_number == 0 {
3233                         return Err(ChannelError::Close("Peer sent a garbage channel_reestablish".to_owned()));
3234                 }
3235
3236                 if msg.next_remote_commitment_number > 0 {
3237                         match msg.data_loss_protect {
3238                                 OptionalField::Present(ref data_loss) => {
3239                                         let expected_point = self.holder_signer.get_per_commitment_point(INITIAL_COMMITMENT_NUMBER - msg.next_remote_commitment_number + 1, &self.secp_ctx);
3240                                         let given_secret = SecretKey::from_slice(&data_loss.your_last_per_commitment_secret)
3241                                                 .map_err(|_| ChannelError::Close("Peer sent a garbage channel_reestablish with unparseable secret key".to_owned()))?;
3242                                         if expected_point != PublicKey::from_secret_key(&self.secp_ctx, &given_secret) {
3243                                                 return Err(ChannelError::Close("Peer sent a garbage channel_reestablish with secret key not matching the commitment height provided".to_owned()));
3244                                         }
3245                                         if msg.next_remote_commitment_number > INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number {
3246                                                 return Err(ChannelError::CloseDelayBroadcast(
3247                                                         "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()
3248                                                 ));
3249                                         }
3250                                 },
3251                                 OptionalField::Absent => {}
3252                         }
3253                 }
3254
3255                 // Go ahead and unmark PeerDisconnected as various calls we may make check for it (and all
3256                 // remaining cases either succeed or ErrorMessage-fail).
3257                 self.channel_state &= !(ChannelState::PeerDisconnected as u32);
3258
3259                 let shutdown_msg = if self.channel_state & (ChannelState::LocalShutdownSent as u32) != 0 {
3260                         assert!(self.shutdown_scriptpubkey.is_some());
3261                         Some(msgs::Shutdown {
3262                                 channel_id: self.channel_id,
3263                                 scriptpubkey: self.get_closing_scriptpubkey(),
3264                         })
3265                 } else { None };
3266
3267                 if self.channel_state & (ChannelState::FundingSent as u32) == ChannelState::FundingSent as u32 {
3268                         // If we're waiting on a monitor update, we shouldn't re-send any funding_locked's.
3269                         if self.channel_state & (ChannelState::OurFundingLocked as u32) == 0 ||
3270                                         self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
3271                                 if msg.next_remote_commitment_number != 0 {
3272                                         return Err(ChannelError::Close("Peer claimed they saw a revoke_and_ack but we haven't sent funding_locked yet".to_owned()));
3273                                 }
3274                                 // Short circuit the whole handler as there is nothing we can resend them
3275                                 return Ok((None, None, None, None, RAACommitmentOrder::CommitmentFirst, Vec::new(), shutdown_msg));
3276                         }
3277
3278                         // We have OurFundingLocked set!
3279                         let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3280                         return Ok((Some(msgs::FundingLocked {
3281                                 channel_id: self.channel_id(),
3282                                 next_per_commitment_point,
3283                         }), None, None, None, RAACommitmentOrder::CommitmentFirst, Vec::new(), shutdown_msg));
3284                 }
3285
3286                 let required_revoke = if msg.next_remote_commitment_number + 1 == INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number {
3287                         // Remote isn't waiting on any RevokeAndACK from us!
3288                         // Note that if we need to repeat our FundingLocked we'll do that in the next if block.
3289                         None
3290                 } else if msg.next_remote_commitment_number + 1 == (INITIAL_COMMITMENT_NUMBER - 1) - self.cur_holder_commitment_transaction_number {
3291                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
3292                                 self.monitor_pending_revoke_and_ack = true;
3293                                 None
3294                         } else {
3295                                 Some(self.get_last_revoke_and_ack())
3296                         }
3297                 } else {
3298                         return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old local commitment transaction".to_owned()));
3299                 };
3300
3301                 // We increment cur_counterparty_commitment_transaction_number only upon receipt of
3302                 // revoke_and_ack, not on sending commitment_signed, so we add one if have
3303                 // AwaitingRemoteRevoke set, which indicates we sent a commitment_signed but haven't gotten
3304                 // the corresponding revoke_and_ack back yet.
3305                 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 };
3306
3307                 let resend_funding_locked = if msg.next_local_commitment_number == 1 && INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number == 1 {
3308                         // We should never have to worry about MonitorUpdateFailed resending FundingLocked
3309                         let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3310                         Some(msgs::FundingLocked {
3311                                 channel_id: self.channel_id(),
3312                                 next_per_commitment_point,
3313                         })
3314                 } else { None };
3315
3316                 if msg.next_local_commitment_number == next_counterparty_commitment_number {
3317                         if required_revoke.is_some() {
3318                                 log_debug!(logger, "Reconnected channel {} with only lost outbound RAA", log_bytes!(self.channel_id()));
3319                         } else {
3320                                 log_debug!(logger, "Reconnected channel {} with no loss", log_bytes!(self.channel_id()));
3321                         }
3322
3323                         if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateFailed as u32)) == 0 {
3324                                 // We're up-to-date and not waiting on a remote revoke (if we are our
3325                                 // channel_reestablish should result in them sending a revoke_and_ack), but we may
3326                                 // have received some updates while we were disconnected. Free the holding cell
3327                                 // now!
3328                                 match self.free_holding_cell_htlcs(logger) {
3329                                         Err(ChannelError::Close(msg)) => return Err(ChannelError::Close(msg)),
3330                                         Err(ChannelError::Warn(_)) | Err(ChannelError::Ignore(_)) | Err(ChannelError::CloseDelayBroadcast(_)) =>
3331                                                 panic!("Got non-channel-failing result from free_holding_cell_htlcs"),
3332                                         Ok((Some((commitment_update, monitor_update)), htlcs_to_fail)) => {
3333                                                 return Ok((resend_funding_locked, required_revoke, Some(commitment_update), Some(monitor_update), self.resend_order.clone(), htlcs_to_fail, shutdown_msg));
3334                                         },
3335                                         Ok((None, htlcs_to_fail)) => {
3336                                                 return Ok((resend_funding_locked, required_revoke, None, None, self.resend_order.clone(), htlcs_to_fail, shutdown_msg));
3337                                         },
3338                                 }
3339                         } else {
3340                                 return Ok((resend_funding_locked, required_revoke, None, None, self.resend_order.clone(), Vec::new(), shutdown_msg));
3341                         }
3342                 } else if msg.next_local_commitment_number == next_counterparty_commitment_number - 1 {
3343                         if required_revoke.is_some() {
3344                                 log_debug!(logger, "Reconnected channel {} with lost outbound RAA and lost remote commitment tx", log_bytes!(self.channel_id()));
3345                         } else {
3346                                 log_debug!(logger, "Reconnected channel {} with only lost remote commitment tx", log_bytes!(self.channel_id()));
3347                         }
3348
3349                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
3350                                 self.monitor_pending_commitment_signed = true;
3351                                 return Ok((resend_funding_locked, None, None, None, self.resend_order.clone(), Vec::new(), shutdown_msg));
3352                         }
3353
3354                         return Ok((resend_funding_locked, required_revoke, Some(self.get_last_commitment_update(logger)), None, self.resend_order.clone(), Vec::new(), shutdown_msg));
3355                 } else {
3356                         return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old remote commitment transaction".to_owned()));
3357                 }
3358         }
3359
3360         /// Calculates and returns our minimum and maximum closing transaction fee amounts, in whole
3361         /// satoshis. The amounts remain consistent unless a peer disconnects/reconnects or we restart,
3362         /// at which point they will be recalculated.
3363         fn calculate_closing_fee_limits<F: Deref>(&mut self, fee_estimator: &F) -> (u64, u64)
3364                 where F::Target: FeeEstimator
3365         {
3366                 if let Some((min, max)) = self.closing_fee_limits { return (min, max); }
3367
3368                 // Propose a range from our current Background feerate to our Normal feerate plus our
3369                 // force_close_avoidance_max_fee_satoshis.
3370                 // If we fail to come to consensus, we'll have to force-close.
3371                 let mut proposed_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
3372                 let normal_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
3373                 let mut proposed_max_feerate = if self.is_outbound() { normal_feerate } else { u32::max_value() };
3374
3375                 // The spec requires that (when the channel does not have anchors) we only send absolute
3376                 // channel fees no greater than the absolute channel fee on the current commitment
3377                 // transaction. It's unclear *which* commitment transaction this refers to, and there isn't
3378                 // very good reason to apply such a limit in any case. We don't bother doing so, risking
3379                 // some force-closure by old nodes, but we wanted to close the channel anyway.
3380
3381                 if let Some(target_feerate) = self.target_closing_feerate_sats_per_kw {
3382                         let min_feerate = if self.is_outbound() { target_feerate } else { cmp::min(self.feerate_per_kw, target_feerate) };
3383                         proposed_feerate = cmp::max(proposed_feerate, min_feerate);
3384                         proposed_max_feerate = cmp::max(proposed_max_feerate, min_feerate);
3385                 }
3386
3387                 // Note that technically we could end up with a lower minimum fee if one sides' balance is
3388                 // below our dust limit, causing the output to disappear. We don't bother handling this
3389                 // case, however, as this should only happen if a channel is closed before any (material)
3390                 // payments have been made on it. This may cause slight fee overpayment and/or failure to
3391                 // come to consensus with our counterparty on appropriate fees, however it should be a
3392                 // relatively rare case. We can revisit this later, though note that in order to determine
3393                 // if the funders' output is dust we have to know the absolute fee we're going to use.
3394                 let tx_weight = self.get_closing_transaction_weight(Some(&self.get_closing_scriptpubkey()), Some(self.counterparty_shutdown_scriptpubkey.as_ref().unwrap()));
3395                 let proposed_total_fee_satoshis = proposed_feerate as u64 * tx_weight / 1000;
3396                 let proposed_max_total_fee_satoshis = if self.is_outbound() {
3397                                 // We always add force_close_avoidance_max_fee_satoshis to our normal
3398                                 // feerate-calculated fee, but allow the max to be overridden if we're using a
3399                                 // target feerate-calculated fee.
3400                                 cmp::max(normal_feerate as u64 * tx_weight / 1000 + self.config.force_close_avoidance_max_fee_satoshis,
3401                                         proposed_max_feerate as u64 * tx_weight / 1000)
3402                         } else {
3403                                 self.channel_value_satoshis - (self.value_to_self_msat + 999) / 1000
3404                         };
3405
3406                 self.closing_fee_limits = Some((proposed_total_fee_satoshis, proposed_max_total_fee_satoshis));
3407                 self.closing_fee_limits.clone().unwrap()
3408         }
3409
3410         /// Returns true if we're ready to commence the closing_signed negotiation phase. This is true
3411         /// after both sides have exchanged a `shutdown` message and all HTLCs have been drained. At
3412         /// this point if we're the funder we should send the initial closing_signed, and in any case
3413         /// shutdown should complete within a reasonable timeframe.
3414         fn closing_negotiation_ready(&self) -> bool {
3415                 self.pending_inbound_htlcs.is_empty() && self.pending_outbound_htlcs.is_empty() &&
3416                         self.channel_state &
3417                                 (BOTH_SIDES_SHUTDOWN_MASK | ChannelState::AwaitingRemoteRevoke as u32 |
3418                                  ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)
3419                                 == BOTH_SIDES_SHUTDOWN_MASK &&
3420                         self.pending_update_fee.is_none()
3421         }
3422
3423         /// Checks if the closing_signed negotiation is making appropriate progress, possibly returning
3424         /// an Err if no progress is being made and the channel should be force-closed instead.
3425         /// Should be called on a one-minute timer.
3426         pub fn timer_check_closing_negotiation_progress(&mut self) -> Result<(), ChannelError> {
3427                 if self.closing_negotiation_ready() {
3428                         if self.closing_signed_in_flight {
3429                                 return Err(ChannelError::Close("closing_signed negotiation failed to finish within two timer ticks".to_owned()));
3430                         } else {
3431                                 self.closing_signed_in_flight = true;
3432                         }
3433                 }
3434                 Ok(())
3435         }
3436
3437         pub fn maybe_propose_closing_signed<F: Deref, L: Deref>(&mut self, fee_estimator: &F, logger: &L)
3438                 -> Result<(Option<msgs::ClosingSigned>, Option<Transaction>), ChannelError>
3439                 where F::Target: FeeEstimator, L::Target: Logger
3440         {
3441                 if self.last_sent_closing_fee.is_some() || !self.closing_negotiation_ready() {
3442                         return Ok((None, None));
3443                 }
3444
3445                 if !self.is_outbound() {
3446                         if let Some(msg) = &self.pending_counterparty_closing_signed.take() {
3447                                 return self.closing_signed(fee_estimator, &msg);
3448                         }
3449                         return Ok((None, None));
3450                 }
3451
3452                 let (our_min_fee, our_max_fee) = self.calculate_closing_fee_limits(fee_estimator);
3453
3454                 assert!(self.shutdown_scriptpubkey.is_some());
3455                 let (closing_tx, total_fee_satoshis) = self.build_closing_transaction(our_min_fee, false);
3456                 log_trace!(logger, "Proposing initial closing_signed for our counterparty with a fee range of {}-{} sat (with initial proposal {} sats)",
3457                         our_min_fee, our_max_fee, total_fee_satoshis);
3458
3459                 let sig = self.holder_signer
3460                         .sign_closing_transaction(&closing_tx, &self.secp_ctx)
3461                         .map_err(|()| ChannelError::Close("Failed to get signature for closing transaction.".to_owned()))?;
3462
3463                 self.last_sent_closing_fee = Some((total_fee_satoshis, sig.clone()));
3464                 Ok((Some(msgs::ClosingSigned {
3465                         channel_id: self.channel_id,
3466                         fee_satoshis: total_fee_satoshis,
3467                         signature: sig,
3468                         fee_range: Some(msgs::ClosingSignedFeeRange {
3469                                 min_fee_satoshis: our_min_fee,
3470                                 max_fee_satoshis: our_max_fee,
3471                         }),
3472                 }), None))
3473         }
3474
3475         pub fn shutdown<K: Deref>(
3476                 &mut self, keys_provider: &K, their_features: &InitFeatures, msg: &msgs::Shutdown
3477         ) -> Result<(Option<msgs::Shutdown>, Option<ChannelMonitorUpdate>, Vec<(HTLCSource, PaymentHash)>), ChannelError>
3478         where K::Target: KeysInterface<Signer = Signer>
3479         {
3480                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
3481                         return Err(ChannelError::Close("Peer sent shutdown when we needed a channel_reestablish".to_owned()));
3482                 }
3483                 if self.channel_state < ChannelState::FundingSent as u32 {
3484                         // Spec says we should fail the connection, not the channel, but that's nonsense, there
3485                         // are plenty of reasons you may want to fail a channel pre-funding, and spec says you
3486                         // can do that via error message without getting a connection fail anyway...
3487                         return Err(ChannelError::Close("Peer sent shutdown pre-funding generation".to_owned()));
3488                 }
3489                 for htlc in self.pending_inbound_htlcs.iter() {
3490                         if let InboundHTLCState::RemoteAnnounced(_) = htlc.state {
3491                                 return Err(ChannelError::Close("Got shutdown with remote pending HTLCs".to_owned()));
3492                         }
3493                 }
3494                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
3495
3496                 if !script::is_bolt2_compliant(&msg.scriptpubkey, their_features) {
3497                         return Err(ChannelError::Close(format!("Got a nonstandard scriptpubkey ({}) from remote peer", msg.scriptpubkey.to_bytes().to_hex())));
3498                 }
3499
3500                 if self.counterparty_shutdown_scriptpubkey.is_some() {
3501                         if Some(&msg.scriptpubkey) != self.counterparty_shutdown_scriptpubkey.as_ref() {
3502                                 return Err(ChannelError::Close(format!("Got shutdown request with a scriptpubkey ({}) which did not match their previous scriptpubkey.", msg.scriptpubkey.to_bytes().to_hex())));
3503                         }
3504                 } else {
3505                         self.counterparty_shutdown_scriptpubkey = Some(msg.scriptpubkey.clone());
3506                 }
3507
3508                 // If we have any LocalAnnounced updates we'll probably just get back an update_fail_htlc
3509                 // immediately after the commitment dance, but we can send a Shutdown because we won't send
3510                 // any further commitment updates after we set LocalShutdownSent.
3511                 let send_shutdown = (self.channel_state & ChannelState::LocalShutdownSent as u32) != ChannelState::LocalShutdownSent as u32;
3512
3513                 let update_shutdown_script = match self.shutdown_scriptpubkey {
3514                         Some(_) => false,
3515                         None => {
3516                                 assert!(send_shutdown);
3517                                 let shutdown_scriptpubkey = keys_provider.get_shutdown_scriptpubkey();
3518                                 if !shutdown_scriptpubkey.is_compatible(their_features) {
3519                                         return Err(ChannelError::Close(format!("Provided a scriptpubkey format not accepted by peer: {}", shutdown_scriptpubkey)));
3520                                 }
3521                                 self.shutdown_scriptpubkey = Some(shutdown_scriptpubkey);
3522                                 true
3523                         },
3524                 };
3525
3526                 // From here on out, we may not fail!
3527
3528                 self.channel_state |= ChannelState::RemoteShutdownSent as u32;
3529                 self.update_time_counter += 1;
3530
3531                 let monitor_update = if update_shutdown_script {
3532                         self.latest_monitor_update_id += 1;
3533                         Some(ChannelMonitorUpdate {
3534                                 update_id: self.latest_monitor_update_id,
3535                                 updates: vec![ChannelMonitorUpdateStep::ShutdownScript {
3536                                         scriptpubkey: self.get_closing_scriptpubkey(),
3537                                 }],
3538                         })
3539                 } else { None };
3540                 let shutdown = if send_shutdown {
3541                         Some(msgs::Shutdown {
3542                                 channel_id: self.channel_id,
3543                                 scriptpubkey: self.get_closing_scriptpubkey(),
3544                         })
3545                 } else { None };
3546
3547                 // We can't send our shutdown until we've committed all of our pending HTLCs, but the
3548                 // remote side is unlikely to accept any new HTLCs, so we go ahead and "free" any holding
3549                 // cell HTLCs and return them to fail the payment.
3550                 self.holding_cell_update_fee = None;
3551                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
3552                 self.holding_cell_htlc_updates.retain(|htlc_update| {
3553                         match htlc_update {
3554                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
3555                                         dropped_outbound_htlcs.push((source.clone(), payment_hash.clone()));
3556                                         false
3557                                 },
3558                                 _ => true
3559                         }
3560                 });
3561
3562                 self.channel_state |= ChannelState::LocalShutdownSent as u32;
3563                 self.update_time_counter += 1;
3564
3565                 Ok((shutdown, monitor_update, dropped_outbound_htlcs))
3566         }
3567
3568         fn build_signed_closing_transaction(&self, closing_tx: &ClosingTransaction, counterparty_sig: &Signature, sig: &Signature) -> Transaction {
3569                 let mut tx = closing_tx.trust().built_transaction().clone();
3570
3571                 tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
3572
3573                 let funding_key = self.get_holder_pubkeys().funding_pubkey.serialize();
3574                 let counterparty_funding_key = self.counterparty_funding_pubkey().serialize();
3575                 if funding_key[..] < counterparty_funding_key[..] {
3576                         tx.input[0].witness.push(sig.serialize_der().to_vec());
3577                         tx.input[0].witness.push(counterparty_sig.serialize_der().to_vec());
3578                 } else {
3579                         tx.input[0].witness.push(counterparty_sig.serialize_der().to_vec());
3580                         tx.input[0].witness.push(sig.serialize_der().to_vec());
3581                 }
3582                 tx.input[0].witness[1].push(SigHashType::All as u8);
3583                 tx.input[0].witness[2].push(SigHashType::All as u8);
3584
3585                 tx.input[0].witness.push(self.get_funding_redeemscript().into_bytes());
3586                 tx
3587         }
3588
3589         pub fn closing_signed<F: Deref>(&mut self, fee_estimator: &F, msg: &msgs::ClosingSigned) -> Result<(Option<msgs::ClosingSigned>, Option<Transaction>), ChannelError>
3590                 where F::Target: FeeEstimator
3591         {
3592                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != BOTH_SIDES_SHUTDOWN_MASK {
3593                         return Err(ChannelError::Close("Remote end sent us a closing_signed before both sides provided a shutdown".to_owned()));
3594                 }
3595                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
3596                         return Err(ChannelError::Close("Peer sent closing_signed when we needed a channel_reestablish".to_owned()));
3597                 }
3598                 if !self.pending_inbound_htlcs.is_empty() || !self.pending_outbound_htlcs.is_empty() {
3599                         return Err(ChannelError::Close("Remote end sent us a closing_signed while there were still pending HTLCs".to_owned()));
3600                 }
3601                 if msg.fee_satoshis > 21_000_000 * 1_0000_0000 { //this is required to stop potential overflow in build_closing_transaction
3602                         return Err(ChannelError::Close("Remote tried to send us a closing tx with > 21 million BTC fee".to_owned()));
3603                 }
3604
3605                 if self.is_outbound() && self.last_sent_closing_fee.is_none() {
3606                         return Err(ChannelError::Close("Remote tried to send a closing_signed when we were supposed to propose the first one".to_owned()));
3607                 }
3608
3609                 if self.channel_state & ChannelState::MonitorUpdateFailed as u32 != 0 {
3610                         self.pending_counterparty_closing_signed = Some(msg.clone());
3611                         return Ok((None, None));
3612                 }
3613
3614                 let funding_redeemscript = self.get_funding_redeemscript();
3615                 let (mut closing_tx, used_total_fee) = self.build_closing_transaction(msg.fee_satoshis, false);
3616                 if used_total_fee != msg.fee_satoshis {
3617                         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)));
3618                 }
3619                 let sighash = closing_tx.trust().get_sighash_all(&funding_redeemscript, self.channel_value_satoshis);
3620
3621                 match self.secp_ctx.verify(&sighash, &msg.signature, &self.get_counterparty_pubkeys().funding_pubkey) {
3622                         Ok(_) => {},
3623                         Err(_e) => {
3624                                 // The remote end may have decided to revoke their output due to inconsistent dust
3625                                 // limits, so check for that case by re-checking the signature here.
3626                                 closing_tx = self.build_closing_transaction(msg.fee_satoshis, true).0;
3627                                 let sighash = closing_tx.trust().get_sighash_all(&funding_redeemscript, self.channel_value_satoshis);
3628                                 secp_check!(self.secp_ctx.verify(&sighash, &msg.signature, self.counterparty_funding_pubkey()), "Invalid closing tx signature from peer".to_owned());
3629                         },
3630                 };
3631
3632                 for outp in closing_tx.trust().built_transaction().output.iter() {
3633                         if !outp.script_pubkey.is_witness_program() && outp.value < MAX_STD_OUTPUT_DUST_LIMIT_SATOSHIS {
3634                                 return Err(ChannelError::Close("Remote sent us a closing_signed with a dust output. Always use segwit closing scripts!".to_owned()));
3635                         }
3636                 }
3637
3638                 assert!(self.shutdown_scriptpubkey.is_some());
3639                 if let Some((last_fee, sig)) = self.last_sent_closing_fee {
3640                         if last_fee == msg.fee_satoshis {
3641                                 let tx = self.build_signed_closing_transaction(&mut closing_tx, &msg.signature, &sig);
3642                                 self.channel_state = ChannelState::ShutdownComplete as u32;
3643                                 self.update_time_counter += 1;
3644                                 return Ok((None, Some(tx)));
3645                         }
3646                 }
3647
3648                 let (our_min_fee, our_max_fee) = self.calculate_closing_fee_limits(fee_estimator);
3649
3650                 macro_rules! propose_fee {
3651                         ($new_fee: expr) => {
3652                                 let (closing_tx, used_fee) = if $new_fee == msg.fee_satoshis {
3653                                         (closing_tx, $new_fee)
3654                                 } else {
3655                                         self.build_closing_transaction($new_fee, false)
3656                                 };
3657
3658                                 let sig = self.holder_signer
3659                                         .sign_closing_transaction(&closing_tx, &self.secp_ctx)
3660                                         .map_err(|_| ChannelError::Close("External signer refused to sign closing transaction".to_owned()))?;
3661
3662                                 let signed_tx = if $new_fee == msg.fee_satoshis {
3663                                         self.channel_state = ChannelState::ShutdownComplete as u32;
3664                                         self.update_time_counter += 1;
3665                                         let tx = self.build_signed_closing_transaction(&closing_tx, &msg.signature, &sig);
3666                                         Some(tx)
3667                                 } else { None };
3668
3669                                 self.last_sent_closing_fee = Some((used_fee, sig.clone()));
3670                                 return Ok((Some(msgs::ClosingSigned {
3671                                         channel_id: self.channel_id,
3672                                         fee_satoshis: used_fee,
3673                                         signature: sig,
3674                                         fee_range: Some(msgs::ClosingSignedFeeRange {
3675                                                 min_fee_satoshis: our_min_fee,
3676                                                 max_fee_satoshis: our_max_fee,
3677                                         }),
3678                                 }), signed_tx))
3679                         }
3680                 }
3681
3682                 if let Some(msgs::ClosingSignedFeeRange { min_fee_satoshis, max_fee_satoshis }) = msg.fee_range {
3683                         if msg.fee_satoshis < min_fee_satoshis || msg.fee_satoshis > max_fee_satoshis {
3684                                 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)));
3685                         }
3686                         if max_fee_satoshis < our_min_fee {
3687                                 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)));
3688                         }
3689                         if min_fee_satoshis > our_max_fee {
3690                                 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)));
3691                         }
3692
3693                         if !self.is_outbound() {
3694                                 // They have to pay, so pick the highest fee in the overlapping range.
3695                                 // We should never set an upper bound aside from their full balance
3696                                 debug_assert_eq!(our_max_fee, self.channel_value_satoshis - (self.value_to_self_msat + 999) / 1000);
3697                                 propose_fee!(cmp::min(max_fee_satoshis, our_max_fee));
3698                         } else {
3699                                 if msg.fee_satoshis < our_min_fee || msg.fee_satoshis > our_max_fee {
3700                                         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.",
3701                                                 msg.fee_satoshis, our_min_fee, our_max_fee)));
3702                                 }
3703                                 // The proposed fee is in our acceptable range, accept it and broadcast!
3704                                 propose_fee!(msg.fee_satoshis);
3705                         }
3706                 } else {
3707                         // Old fee style negotiation. We don't bother to enforce whether they are complying
3708                         // with the "making progress" requirements, we just comply and hope for the best.
3709                         if let Some((last_fee, _)) = self.last_sent_closing_fee {
3710                                 if msg.fee_satoshis > last_fee {
3711                                         if msg.fee_satoshis < our_max_fee {
3712                                                 propose_fee!(msg.fee_satoshis);
3713                                         } else if last_fee < our_max_fee {
3714                                                 propose_fee!(our_max_fee);
3715                                         } else {
3716                                                 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)));
3717                                         }
3718                                 } else {
3719                                         if msg.fee_satoshis > our_min_fee {
3720                                                 propose_fee!(msg.fee_satoshis);
3721                                         } else if last_fee > our_min_fee {
3722                                                 propose_fee!(our_min_fee);
3723                                         } else {
3724                                                 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)));
3725                                         }
3726                                 }
3727                         } else {
3728                                 if msg.fee_satoshis < our_min_fee {
3729                                         propose_fee!(our_min_fee);
3730                                 } else if msg.fee_satoshis > our_max_fee {
3731                                         propose_fee!(our_max_fee);
3732                                 } else {
3733                                         propose_fee!(msg.fee_satoshis);
3734                                 }
3735                         }
3736                 }
3737         }
3738
3739         // Public utilities:
3740
3741         pub fn channel_id(&self) -> [u8; 32] {
3742                 self.channel_id
3743         }
3744
3745         pub fn minimum_depth(&self) -> Option<u32> {
3746                 self.minimum_depth
3747         }
3748
3749         /// Gets the "user_id" value passed into the construction of this channel. It has no special
3750         /// meaning and exists only to allow users to have a persistent identifier of a channel.
3751         pub fn get_user_id(&self) -> u64 {
3752                 self.user_id
3753         }
3754
3755         /// Guaranteed to be Some after both FundingLocked messages have been exchanged (and, thus,
3756         /// is_usable() returns true).
3757         /// Allowed in any state (including after shutdown)
3758         pub fn get_short_channel_id(&self) -> Option<u64> {
3759                 self.short_channel_id
3760         }
3761
3762         /// Returns the funding_txo we either got from our peer, or were given by
3763         /// get_outbound_funding_created.
3764         pub fn get_funding_txo(&self) -> Option<OutPoint> {
3765                 self.channel_transaction_parameters.funding_outpoint
3766         }
3767
3768         fn get_holder_selected_contest_delay(&self) -> u16 {
3769                 self.channel_transaction_parameters.holder_selected_contest_delay
3770         }
3771
3772         fn get_holder_pubkeys(&self) -> &ChannelPublicKeys {
3773                 &self.channel_transaction_parameters.holder_pubkeys
3774         }
3775
3776         pub fn get_counterparty_selected_contest_delay(&self) -> Option<u16> {
3777                 self.channel_transaction_parameters.counterparty_parameters
3778                         .as_ref().map(|params| params.selected_contest_delay)
3779         }
3780
3781         fn get_counterparty_pubkeys(&self) -> &ChannelPublicKeys {
3782                 &self.channel_transaction_parameters.counterparty_parameters.as_ref().unwrap().pubkeys
3783         }
3784
3785         /// Allowed in any state (including after shutdown)
3786         pub fn get_counterparty_node_id(&self) -> PublicKey {
3787                 self.counterparty_node_id
3788         }
3789
3790         /// Allowed in any state (including after shutdown)
3791         #[cfg(test)]
3792         pub fn get_holder_htlc_minimum_msat(&self) -> u64 {
3793                 self.holder_htlc_minimum_msat
3794         }
3795
3796         /// Allowed in any state (including after shutdown)
3797         pub fn get_announced_htlc_max_msat(&self) -> u64 {
3798                 return cmp::min(
3799                         // Upper bound by capacity. We make it a bit less than full capacity to prevent attempts
3800                         // to use full capacity. This is an effort to reduce routing failures, because in many cases
3801                         // channel might have been used to route very small values (either by honest users or as DoS).
3802                         self.channel_value_satoshis * 1000 * 9 / 10,
3803
3804                         Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis)
3805                 );
3806         }
3807
3808         /// Allowed in any state (including after shutdown)
3809         pub fn get_counterparty_htlc_minimum_msat(&self) -> u64 {
3810                 self.counterparty_htlc_minimum_msat
3811         }
3812
3813         pub fn get_value_satoshis(&self) -> u64 {
3814                 self.channel_value_satoshis
3815         }
3816
3817         pub fn get_fee_proportional_millionths(&self) -> u32 {
3818                 self.config.forwarding_fee_proportional_millionths
3819         }
3820
3821         pub fn get_cltv_expiry_delta(&self) -> u16 {
3822                 cmp::max(self.config.cltv_expiry_delta, MIN_CLTV_EXPIRY_DELTA)
3823         }
3824
3825         pub fn get_max_dust_htlc_exposure_msat(&self) -> u64 {
3826                 self.config.max_dust_htlc_exposure_msat
3827         }
3828
3829         pub fn get_feerate(&self) -> u32 {
3830                 self.feerate_per_kw
3831         }
3832
3833         pub fn get_dust_buffer_feerate(&self) -> u32 {
3834                 // When calculating our exposure to dust HTLCs, we assume that the channel feerate
3835                 // may, at any point, increase by at least 10 sat/vB (i.e 2530 sat/kWU) or 25%,
3836                 // whichever is higher. This ensures that we aren't suddenly exposed to significantly
3837                 // more dust balance if the feerate increases when we have several HTLCs pending
3838                 // which are near the dust limit.
3839                 let mut feerate_per_kw = self.feerate_per_kw;
3840                 // If there's a pending update fee, use it to ensure we aren't under-estimating
3841                 // potential feerate updates coming soon.
3842                 if let Some((feerate, _)) = self.pending_update_fee {
3843                         feerate_per_kw = cmp::max(feerate_per_kw, feerate);
3844                 }
3845                 cmp::max(2530, feerate_per_kw * 1250 / 1000)
3846         }
3847
3848         pub fn get_cur_holder_commitment_transaction_number(&self) -> u64 {
3849                 self.cur_holder_commitment_transaction_number + 1
3850         }
3851
3852         pub fn get_cur_counterparty_commitment_transaction_number(&self) -> u64 {
3853                 self.cur_counterparty_commitment_transaction_number + 1 - if self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32) != 0 { 1 } else { 0 }
3854         }
3855
3856         pub fn get_revoked_counterparty_commitment_transaction_number(&self) -> u64 {
3857                 self.cur_counterparty_commitment_transaction_number + 2
3858         }
3859
3860         #[cfg(test)]
3861         pub fn get_signer(&self) -> &Signer {
3862                 &self.holder_signer
3863         }
3864
3865         #[cfg(test)]
3866         pub fn get_value_stat(&self) -> ChannelValueStat {
3867                 ChannelValueStat {
3868                         value_to_self_msat: self.value_to_self_msat,
3869                         channel_value_msat: self.channel_value_satoshis * 1000,
3870                         channel_reserve_msat: self.counterparty_selected_channel_reserve_satoshis.unwrap() * 1000,
3871                         pending_outbound_htlcs_amount_msat: self.pending_outbound_htlcs.iter().map(|ref h| h.amount_msat).sum::<u64>(),
3872                         pending_inbound_htlcs_amount_msat: self.pending_inbound_htlcs.iter().map(|ref h| h.amount_msat).sum::<u64>(),
3873                         holding_cell_outbound_amount_msat: {
3874                                 let mut res = 0;
3875                                 for h in self.holding_cell_htlc_updates.iter() {
3876                                         match h {
3877                                                 &HTLCUpdateAwaitingACK::AddHTLC{amount_msat, .. } => {
3878                                                         res += amount_msat;
3879                                                 }
3880                                                 _ => {}
3881                                         }
3882                                 }
3883                                 res
3884                         },
3885                         counterparty_max_htlc_value_in_flight_msat: self.counterparty_max_htlc_value_in_flight_msat,
3886                         counterparty_dust_limit_msat: self.counterparty_dust_limit_satoshis * 1000,
3887                 }
3888         }
3889
3890         /// Allowed in any state (including after shutdown)
3891         pub fn get_update_time_counter(&self) -> u32 {
3892                 self.update_time_counter
3893         }
3894
3895         pub fn get_latest_monitor_update_id(&self) -> u64 {
3896                 self.latest_monitor_update_id
3897         }
3898
3899         pub fn should_announce(&self) -> bool {
3900                 self.config.announced_channel
3901         }
3902
3903         pub fn is_outbound(&self) -> bool {
3904                 self.channel_transaction_parameters.is_outbound_from_holder
3905         }
3906
3907         /// Gets the fee we'd want to charge for adding an HTLC output to this Channel
3908         /// Allowed in any state (including after shutdown)
3909         pub fn get_outbound_forwarding_fee_base_msat(&self) -> u32 {
3910                 self.config.forwarding_fee_base_msat
3911         }
3912
3913         /// Returns true if we've ever received a message from the remote end for this Channel
3914         pub fn have_received_message(&self) -> bool {
3915                 self.channel_state > (ChannelState::OurInitSent as u32)
3916         }
3917
3918         /// Returns true if this channel is fully established and not known to be closing.
3919         /// Allowed in any state (including after shutdown)
3920         pub fn is_usable(&self) -> bool {
3921                 let mask = ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK;
3922                 (self.channel_state & mask) == (ChannelState::ChannelFunded as u32)
3923         }
3924
3925         /// Returns true if this channel is currently available for use. This is a superset of
3926         /// is_usable() and considers things like the channel being temporarily disabled.
3927         /// Allowed in any state (including after shutdown)
3928         pub fn is_live(&self) -> bool {
3929                 self.is_usable() && (self.channel_state & (ChannelState::PeerDisconnected as u32) == 0)
3930         }
3931
3932         /// Returns true if this channel has been marked as awaiting a monitor update to move forward.
3933         /// Allowed in any state (including after shutdown)
3934         pub fn is_awaiting_monitor_update(&self) -> bool {
3935                 (self.channel_state & ChannelState::MonitorUpdateFailed as u32) != 0
3936         }
3937
3938         /// Returns true if funding_created was sent/received.
3939         pub fn is_funding_initiated(&self) -> bool {
3940                 self.channel_state >= ChannelState::FundingSent as u32
3941         }
3942
3943         /// Returns true if our peer has either initiated or agreed to shut down the channel.
3944         pub fn received_shutdown(&self) -> bool {
3945                 (self.channel_state & ChannelState::RemoteShutdownSent as u32) != 0
3946         }
3947
3948         /// Returns true if we either initiated or agreed to shut down the channel.
3949         pub fn sent_shutdown(&self) -> bool {
3950                 (self.channel_state & ChannelState::LocalShutdownSent as u32) != 0
3951         }
3952
3953         /// Returns true if this channel is fully shut down. True here implies that no further actions
3954         /// may/will be taken on this channel, and thus this object should be freed. Any future changes
3955         /// will be handled appropriately by the chain monitor.
3956         pub fn is_shutdown(&self) -> bool {
3957                 if (self.channel_state & ChannelState::ShutdownComplete as u32) == ChannelState::ShutdownComplete as u32  {
3958                         assert!(self.channel_state == ChannelState::ShutdownComplete as u32);
3959                         true
3960                 } else { false }
3961         }
3962
3963         pub fn channel_update_status(&self) -> ChannelUpdateStatus {
3964                 self.channel_update_status
3965         }
3966
3967         pub fn set_channel_update_status(&mut self, status: ChannelUpdateStatus) {
3968                 self.channel_update_status = status;
3969         }
3970
3971         fn check_get_funding_locked(&mut self, height: u32) -> Option<msgs::FundingLocked> {
3972                 if self.funding_tx_confirmation_height == 0 {
3973                         return None;
3974                 }
3975
3976                 let funding_tx_confirmations = height as i64 - self.funding_tx_confirmation_height as i64 + 1;
3977                 if funding_tx_confirmations <= 0 {
3978                         self.funding_tx_confirmation_height = 0;
3979                 }
3980
3981                 if funding_tx_confirmations < self.minimum_depth.unwrap_or(0) as i64 {
3982                         return None;
3983                 }
3984
3985                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
3986                 let need_commitment_update = if non_shutdown_state == ChannelState::FundingSent as u32 {
3987                         self.channel_state |= ChannelState::OurFundingLocked as u32;
3988                         true
3989                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32) {
3990                         self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
3991                         self.update_time_counter += 1;
3992                         true
3993                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) {
3994                         // We got a reorg but not enough to trigger a force close, just ignore.
3995                         false
3996                 } else if self.channel_state < ChannelState::ChannelFunded as u32 {
3997                         panic!("Started confirming a channel in a state pre-FundingSent?: {}", self.channel_state);
3998                 } else {
3999                         // We got a reorg but not enough to trigger a force close, just ignore.
4000                         false
4001                 };
4002
4003                 if need_commitment_update {
4004                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) == 0 {
4005                                 let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
4006                                 return Some(msgs::FundingLocked {
4007                                         channel_id: self.channel_id,
4008                                         next_per_commitment_point,
4009                                 });
4010                         } else {
4011                                 self.monitor_pending_funding_locked = true;
4012                         }
4013                 }
4014                 None
4015         }
4016
4017         /// When a transaction is confirmed, we check whether it is or spends the funding transaction
4018         /// In the first case, we store the confirmation height and calculating the short channel id.
4019         /// In the second, we simply return an Err indicating we need to be force-closed now.
4020         pub fn transactions_confirmed<L: Deref>(&mut self, block_hash: &BlockHash, height: u32, txdata: &TransactionData, logger: &L)
4021                         -> Result<Option<msgs::FundingLocked>, msgs::ErrorMessage> where L::Target: Logger {
4022                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
4023                 for &(index_in_block, tx) in txdata.iter() {
4024                         if let Some(funding_txo) = self.get_funding_txo() {
4025                                 // If we haven't yet sent a funding_locked, but are in FundingSent (ignoring
4026                                 // whether they've sent a funding_locked or not), check if we should send one.
4027                                 if non_shutdown_state & !(ChannelState::TheirFundingLocked as u32) == ChannelState::FundingSent as u32 {
4028                                         if tx.txid() == funding_txo.txid {
4029                                                 let txo_idx = funding_txo.index as usize;
4030                                                 if txo_idx >= tx.output.len() || tx.output[txo_idx].script_pubkey != self.get_funding_redeemscript().to_v0_p2wsh() ||
4031                                                                 tx.output[txo_idx].value != self.channel_value_satoshis {
4032                                                         if self.is_outbound() {
4033                                                                 // If we generated the funding transaction and it doesn't match what it
4034                                                                 // should, the client is really broken and we should just panic and
4035                                                                 // tell them off. That said, because hash collisions happen with high
4036                                                                 // probability in fuzztarget mode, if we're fuzzing we just close the
4037                                                                 // channel and move on.
4038                                                                 #[cfg(not(feature = "fuzztarget"))]
4039                                                                 panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
4040                                                         }
4041                                                         self.update_time_counter += 1;
4042                                                         return Err(msgs::ErrorMessage {
4043                                                                 channel_id: self.channel_id(),
4044                                                                 data: "funding tx had wrong script/value or output index".to_owned()
4045                                                         });
4046                                                 } else {
4047                                                         if self.is_outbound() {
4048                                                                 for input in tx.input.iter() {
4049                                                                         if input.witness.is_empty() {
4050                                                                                 // We generated a malleable funding transaction, implying we've
4051                                                                                 // just exposed ourselves to funds loss to our counterparty.
4052                                                                                 #[cfg(not(feature = "fuzztarget"))]
4053                                                                                 panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
4054                                                                         }
4055                                                                 }
4056                                                         }
4057                                                         self.funding_tx_confirmation_height = height;
4058                                                         self.funding_tx_confirmed_in = Some(*block_hash);
4059                                                         self.short_channel_id = match scid_from_parts(height as u64, index_in_block as u64, txo_idx as u64) {
4060                                                                 Ok(scid) => Some(scid),
4061                                                                 Err(_) => panic!("Block was bogus - either height was > 16 million, had > 16 million transactions, or had > 65k outputs"),
4062                                                         }
4063                                                 }
4064                                         }
4065                                         // If we allow 1-conf funding, we may need to check for funding_locked here and
4066                                         // send it immediately instead of waiting for a best_block_updated call (which
4067                                         // may have already happened for this block).
4068                                         if let Some(funding_locked) = self.check_get_funding_locked(height) {
4069                                                 log_info!(logger, "Sending a funding_locked to our peer for channel {}", log_bytes!(self.channel_id));
4070                                                 return Ok(Some(funding_locked));
4071                                         }
4072                                 }
4073                                 for inp in tx.input.iter() {
4074                                         if inp.previous_output == funding_txo.into_bitcoin_outpoint() {
4075                                                 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()));
4076                                                 return Err(msgs::ErrorMessage {
4077                                                         channel_id: self.channel_id(),
4078                                                         data: "Commitment or closing transaction was confirmed on chain.".to_owned()
4079                                                 });
4080                                         }
4081                                 }
4082                         }
4083                 }
4084                 Ok(None)
4085         }
4086
4087         /// When a new block is connected, we check the height of the block against outbound holding
4088         /// cell HTLCs in case we need to give up on them prematurely and time them out. Everything
4089         /// else (e.g. commitment transaction broadcasts, HTLC transaction broadcasting, etc) is
4090         /// handled by the ChannelMonitor.
4091         ///
4092         /// If we return Err, the channel may have been closed, at which point the standard
4093         /// requirements apply - no calls may be made except those explicitly stated to be allowed
4094         /// post-shutdown.
4095         ///
4096         /// May return some HTLCs (and their payment_hash) which have timed out and should be failed
4097         /// back.
4098         pub fn best_block_updated<L: Deref>(&mut self, height: u32, highest_header_time: u32, logger: &L)
4099                         -> Result<(Option<msgs::FundingLocked>, Vec<(HTLCSource, PaymentHash)>), msgs::ErrorMessage> where L::Target: Logger {
4100                 let mut timed_out_htlcs = Vec::new();
4101                 let unforwarded_htlc_cltv_limit = height + HTLC_FAIL_BACK_BUFFER;
4102                 self.holding_cell_htlc_updates.retain(|htlc_update| {
4103                         match htlc_update {
4104                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, ref cltv_expiry, .. } => {
4105                                         if *cltv_expiry <= unforwarded_htlc_cltv_limit {
4106                                                 timed_out_htlcs.push((source.clone(), payment_hash.clone()));
4107                                                 false
4108                                         } else { true }
4109                                 },
4110                                 _ => true
4111                         }
4112                 });
4113
4114                 self.update_time_counter = cmp::max(self.update_time_counter, highest_header_time);
4115
4116                 if let Some(funding_locked) = self.check_get_funding_locked(height) {
4117                         log_info!(logger, "Sending a funding_locked to our peer for channel {}", log_bytes!(self.channel_id));
4118                         return Ok((Some(funding_locked), timed_out_htlcs));
4119                 }
4120
4121                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
4122                 if non_shutdown_state >= ChannelState::ChannelFunded as u32 ||
4123                    (non_shutdown_state & ChannelState::OurFundingLocked as u32) == ChannelState::OurFundingLocked as u32 {
4124                         let mut funding_tx_confirmations = height as i64 - self.funding_tx_confirmation_height as i64 + 1;
4125                         if self.funding_tx_confirmation_height == 0 {
4126                                 // Note that check_get_funding_locked may reset funding_tx_confirmation_height to
4127                                 // zero if it has been reorged out, however in either case, our state flags
4128                                 // indicate we've already sent a funding_locked
4129                                 funding_tx_confirmations = 0;
4130                         }
4131
4132                         // If we've sent funding_locked (or have both sent and received funding_locked), and
4133                         // the funding transaction's confirmation count has dipped below minimum_depth / 2,
4134                         // close the channel and hope we can get the latest state on chain (because presumably
4135                         // the funding transaction is at least still in the mempool of most nodes).
4136                         if funding_tx_confirmations < self.minimum_depth.unwrap() as i64 / 2 {
4137                                 return Err(msgs::ErrorMessage {
4138                                         channel_id: self.channel_id(),
4139                                         data: format!("Funding transaction was un-confirmed. Locked at {} confs, now have {} confs.", self.minimum_depth.unwrap(), funding_tx_confirmations),
4140                                 });
4141                         }
4142                 }
4143
4144                 Ok((None, timed_out_htlcs))
4145         }
4146
4147         /// Indicates the funding transaction is no longer confirmed in the main chain. This may
4148         /// force-close the channel, but may also indicate a harmless reorganization of a block or two
4149         /// before the channel has reached funding_locked and we can just wait for more blocks.
4150         pub fn funding_transaction_unconfirmed<L: Deref>(&mut self, logger: &L) -> Result<(), msgs::ErrorMessage> where L::Target: Logger {
4151                 if self.funding_tx_confirmation_height != 0 {
4152                         // We handle the funding disconnection by calling best_block_updated with a height one
4153                         // below where our funding was connected, implying a reorg back to conf_height - 1.
4154                         let reorg_height = self.funding_tx_confirmation_height - 1;
4155                         // We use the time field to bump the current time we set on channel updates if its
4156                         // larger. If we don't know that time has moved forward, we can just set it to the last
4157                         // time we saw and it will be ignored.
4158                         let best_time = self.update_time_counter;
4159                         match self.best_block_updated(reorg_height, best_time, logger) {
4160                                 Ok((funding_locked, timed_out_htlcs)) => {
4161                                         assert!(funding_locked.is_none(), "We can't generate a funding with 0 confirmations?");
4162                                         assert!(timed_out_htlcs.is_empty(), "We can't have accepted HTLCs with a timeout before our funding confirmation?");
4163                                         Ok(())
4164                                 },
4165                                 Err(e) => Err(e)
4166                         }
4167                 } else {
4168                         // We never learned about the funding confirmation anyway, just ignore
4169                         Ok(())
4170                 }
4171         }
4172
4173         // Methods to get unprompted messages to send to the remote end (or where we already returned
4174         // something in the handler for the message that prompted this message):
4175
4176         pub fn get_open_channel(&self, chain_hash: BlockHash) -> msgs::OpenChannel {
4177                 if !self.is_outbound() {
4178                         panic!("Tried to open a channel for an inbound channel?");
4179                 }
4180                 if self.channel_state != ChannelState::OurInitSent as u32 {
4181                         panic!("Cannot generate an open_channel after we've moved forward");
4182                 }
4183
4184                 if self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
4185                         panic!("Tried to send an open_channel for a channel that has already advanced");
4186                 }
4187
4188                 let first_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
4189                 let keys = self.get_holder_pubkeys();
4190
4191                 msgs::OpenChannel {
4192                         chain_hash,
4193                         temporary_channel_id: self.channel_id,
4194                         funding_satoshis: self.channel_value_satoshis,
4195                         push_msat: self.channel_value_satoshis * 1000 - self.value_to_self_msat,
4196                         dust_limit_satoshis: self.holder_dust_limit_satoshis,
4197                         max_htlc_value_in_flight_msat: Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis),
4198                         channel_reserve_satoshis: Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis),
4199                         htlc_minimum_msat: self.holder_htlc_minimum_msat,
4200                         feerate_per_kw: self.feerate_per_kw as u32,
4201                         to_self_delay: self.get_holder_selected_contest_delay(),
4202                         max_accepted_htlcs: OUR_MAX_HTLCS,
4203                         funding_pubkey: keys.funding_pubkey,
4204                         revocation_basepoint: keys.revocation_basepoint,
4205                         payment_point: keys.payment_point,
4206                         delayed_payment_basepoint: keys.delayed_payment_basepoint,
4207                         htlc_basepoint: keys.htlc_basepoint,
4208                         first_per_commitment_point,
4209                         channel_flags: if self.config.announced_channel {1} else {0},
4210                         shutdown_scriptpubkey: OptionalField::Present(match &self.shutdown_scriptpubkey {
4211                                 Some(script) => script.clone().into_inner(),
4212                                 None => Builder::new().into_script(),
4213                         }),
4214                 }
4215         }
4216
4217         pub fn get_accept_channel(&self) -> msgs::AcceptChannel {
4218                 if self.is_outbound() {
4219                         panic!("Tried to send accept_channel for an outbound channel?");
4220                 }
4221                 if self.channel_state != (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32) {
4222                         panic!("Tried to send accept_channel after channel had moved forward");
4223                 }
4224                 if self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
4225                         panic!("Tried to send an accept_channel for a channel that has already advanced");
4226                 }
4227
4228                 let first_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
4229                 let keys = self.get_holder_pubkeys();
4230
4231                 msgs::AcceptChannel {
4232                         temporary_channel_id: self.channel_id,
4233                         dust_limit_satoshis: self.holder_dust_limit_satoshis,
4234                         max_htlc_value_in_flight_msat: Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis),
4235                         channel_reserve_satoshis: Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis),
4236                         htlc_minimum_msat: self.holder_htlc_minimum_msat,
4237                         minimum_depth: self.minimum_depth.unwrap(),
4238                         to_self_delay: self.get_holder_selected_contest_delay(),
4239                         max_accepted_htlcs: OUR_MAX_HTLCS,
4240                         funding_pubkey: keys.funding_pubkey,
4241                         revocation_basepoint: keys.revocation_basepoint,
4242                         payment_point: keys.payment_point,
4243                         delayed_payment_basepoint: keys.delayed_payment_basepoint,
4244                         htlc_basepoint: keys.htlc_basepoint,
4245                         first_per_commitment_point,
4246                         shutdown_scriptpubkey: OptionalField::Present(match &self.shutdown_scriptpubkey {
4247                                 Some(script) => script.clone().into_inner(),
4248                                 None => Builder::new().into_script(),
4249                         }),
4250                 }
4251         }
4252
4253         /// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
4254         fn get_outbound_funding_created_signature<L: Deref>(&mut self, logger: &L) -> Result<Signature, ChannelError> where L::Target: Logger {
4255                 let counterparty_keys = self.build_remote_transaction_keys()?;
4256                 let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).0;
4257                 Ok(self.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, &self.secp_ctx)
4258                                 .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0)
4259         }
4260
4261         /// Updates channel state with knowledge of the funding transaction's txid/index, and generates
4262         /// a funding_created message for the remote peer.
4263         /// Panics if called at some time other than immediately after initial handshake, if called twice,
4264         /// or if called on an inbound channel.
4265         /// Note that channel_id changes during this call!
4266         /// Do NOT broadcast the funding transaction until after a successful funding_signed call!
4267         /// If an Err is returned, it is a ChannelError::Close.
4268         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 {
4269                 if !self.is_outbound() {
4270                         panic!("Tried to create outbound funding_created message on an inbound channel!");
4271                 }
4272                 if self.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
4273                         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)");
4274                 }
4275                 if self.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
4276                                 self.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
4277                                 self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
4278                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
4279                 }
4280
4281                 self.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
4282                 self.holder_signer.ready_channel(&self.channel_transaction_parameters);
4283
4284                 let signature = match self.get_outbound_funding_created_signature(logger) {
4285                         Ok(res) => res,
4286                         Err(e) => {
4287                                 log_error!(logger, "Got bad signatures: {:?}!", e);
4288                                 self.channel_transaction_parameters.funding_outpoint = None;
4289                                 return Err(e);
4290                         }
4291                 };
4292
4293                 let temporary_channel_id = self.channel_id;
4294
4295                 // Now that we're past error-generating stuff, update our local state:
4296
4297                 self.channel_state = ChannelState::FundingCreated as u32;
4298                 self.channel_id = funding_txo.to_channel_id();
4299                 self.funding_transaction = Some(funding_transaction);
4300
4301                 Ok(msgs::FundingCreated {
4302                         temporary_channel_id,
4303                         funding_txid: funding_txo.txid,
4304                         funding_output_index: funding_txo.index,
4305                         signature
4306                 })
4307         }
4308
4309         /// Gets an UnsignedChannelAnnouncement, as well as a signature covering it using our
4310         /// bitcoin_key, if available, for this channel. The channel must be publicly announceable and
4311         /// available for use (have exchanged FundingLocked messages in both directions). Should be used
4312         /// for both loose and in response to an AnnouncementSignatures message from the remote peer.
4313         /// Will only fail if we're not in a state where channel_announcement may be sent (including
4314         /// closing).
4315         /// Note that the "channel must be funded" requirement is stricter than BOLT 7 requires - see
4316         /// https://github.com/lightningnetwork/lightning-rfc/issues/468
4317         ///
4318         /// This will only return ChannelError::Ignore upon failure.
4319         pub fn get_channel_announcement(&self, node_id: PublicKey, chain_hash: BlockHash) -> Result<(msgs::UnsignedChannelAnnouncement, Signature), ChannelError> {
4320                 if !self.config.announced_channel {
4321                         return Err(ChannelError::Ignore("Channel is not available for public announcements".to_owned()));
4322                 }
4323                 if self.channel_state & (ChannelState::ChannelFunded as u32) == 0 {
4324                         return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement until the channel funding has been locked".to_owned()));
4325                 }
4326                 if (self.channel_state & (ChannelState::LocalShutdownSent as u32 | ChannelState::ShutdownComplete as u32)) != 0 {
4327                         return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement once the channel is closing".to_owned()));
4328                 }
4329
4330                 let were_node_one = node_id.serialize()[..] < self.counterparty_node_id.serialize()[..];
4331
4332                 let msg = msgs::UnsignedChannelAnnouncement {
4333                         features: ChannelFeatures::known(),
4334                         chain_hash,
4335                         short_channel_id: self.get_short_channel_id().unwrap(),
4336                         node_id_1: if were_node_one { node_id } else { self.get_counterparty_node_id() },
4337                         node_id_2: if were_node_one { self.get_counterparty_node_id() } else { node_id },
4338                         bitcoin_key_1: if were_node_one { self.get_holder_pubkeys().funding_pubkey } else { self.counterparty_funding_pubkey().clone() },
4339                         bitcoin_key_2: if were_node_one { self.counterparty_funding_pubkey().clone() } else { self.get_holder_pubkeys().funding_pubkey },
4340                         excess_data: Vec::new(),
4341                 };
4342
4343                 let sig = self.holder_signer.sign_channel_announcement(&msg, &self.secp_ctx)
4344                         .map_err(|_| ChannelError::Ignore("Signer rejected channel_announcement".to_owned()))?;
4345
4346                 Ok((msg, sig))
4347         }
4348
4349         /// Signs the given channel announcement, returning a ChannelError::Ignore if no keys are
4350         /// available.
4351         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> {
4352                 if let Some((their_node_sig, their_bitcoin_sig)) = self.announcement_sigs {
4353                         let were_node_one = announcement.node_id_1 == our_node_id;
4354
4355                         let our_node_sig = self.secp_ctx.sign(&msghash, our_node_secret);
4356                         Ok(msgs::ChannelAnnouncement {
4357                                 node_signature_1: if were_node_one { our_node_sig } else { their_node_sig },
4358                                 node_signature_2: if were_node_one { their_node_sig } else { our_node_sig },
4359                                 bitcoin_signature_1: if were_node_one { our_bitcoin_sig } else { their_bitcoin_sig },
4360                                 bitcoin_signature_2: if were_node_one { their_bitcoin_sig } else { our_bitcoin_sig },
4361                                 contents: announcement,
4362                         })
4363                 } else {
4364                         Err(ChannelError::Ignore("Attempted to sign channel announcement before we'd received announcement_signatures".to_string()))
4365                 }
4366         }
4367
4368         /// Processes an incoming announcement_signatures message, providing a fully-signed
4369         /// channel_announcement message which we can broadcast and storing our counterparty's
4370         /// signatures for later reconstruction/rebroadcast of the channel_announcement.
4371         pub fn announcement_signatures(&mut self, our_node_secret: &SecretKey, our_node_id: PublicKey, chain_hash: BlockHash, msg: &msgs::AnnouncementSignatures) -> Result<msgs::ChannelAnnouncement, ChannelError> {
4372                 let (announcement, our_bitcoin_sig) = self.get_channel_announcement(our_node_id.clone(), chain_hash)?;
4373
4374                 let msghash = hash_to_message!(&Sha256d::hash(&announcement.encode()[..])[..]);
4375
4376                 if self.secp_ctx.verify(&msghash, &msg.node_signature, &self.get_counterparty_node_id()).is_err() {
4377                         return Err(ChannelError::Close(format!(
4378                                 "Bad announcement_signatures. Failed to verify node_signature. UnsignedChannelAnnouncement used for verification is {:?}. their_node_key is {:?}",
4379                                  &announcement, self.get_counterparty_node_id())));
4380                 }
4381                 if self.secp_ctx.verify(&msghash, &msg.bitcoin_signature, self.counterparty_funding_pubkey()).is_err() {
4382                         return Err(ChannelError::Close(format!(
4383                                 "Bad announcement_signatures. Failed to verify bitcoin_signature. UnsignedChannelAnnouncement used for verification is {:?}. their_bitcoin_key is ({:?})",
4384                                 &announcement, self.counterparty_funding_pubkey())));
4385                 }
4386
4387                 self.announcement_sigs = Some((msg.node_signature, msg.bitcoin_signature));
4388
4389                 self.sign_channel_announcement(our_node_secret, our_node_id, msghash, announcement, our_bitcoin_sig)
4390         }
4391
4392         /// Gets a signed channel_announcement for this channel, if we previously received an
4393         /// announcement_signatures from our counterparty.
4394         pub fn get_signed_channel_announcement(&self, our_node_secret: &SecretKey, our_node_id: PublicKey, chain_hash: BlockHash) -> Option<msgs::ChannelAnnouncement> {
4395                 let (announcement, our_bitcoin_sig) = match self.get_channel_announcement(our_node_id.clone(), chain_hash) {
4396                         Ok(res) => res,
4397                         Err(_) => return None,
4398                 };
4399                 let msghash = hash_to_message!(&Sha256d::hash(&announcement.encode()[..])[..]);
4400                 match self.sign_channel_announcement(our_node_secret, our_node_id, msghash, announcement, our_bitcoin_sig) {
4401                         Ok(res) => Some(res),
4402                         Err(_) => None,
4403                 }
4404         }
4405
4406         /// May panic if called on a channel that wasn't immediately-previously
4407         /// self.remove_uncommitted_htlcs_and_mark_paused()'d
4408         pub fn get_channel_reestablish<L: Deref>(&self, logger: &L) -> msgs::ChannelReestablish where L::Target: Logger {
4409                 assert_eq!(self.channel_state & ChannelState::PeerDisconnected as u32, ChannelState::PeerDisconnected as u32);
4410                 assert_ne!(self.cur_counterparty_commitment_transaction_number, INITIAL_COMMITMENT_NUMBER);
4411                 // Prior to static_remotekey, my_current_per_commitment_point was critical to claiming
4412                 // current to_remote balances. However, it no longer has any use, and thus is now simply
4413                 // set to a dummy (but valid, as required by the spec) public key.
4414                 // fuzztarget mode marks a subset of pubkeys as invalid so that we can hit "invalid pubkey"
4415                 // branches, but we unwrap it below, so we arbitrarily select a dummy pubkey which is both
4416                 // valid, and valid in fuzztarget mode's arbitrary validity criteria:
4417                 let mut pk = [2; 33]; pk[1] = 0xff;
4418                 let dummy_pubkey = PublicKey::from_slice(&pk).unwrap();
4419                 let data_loss_protect = if self.cur_counterparty_commitment_transaction_number + 1 < INITIAL_COMMITMENT_NUMBER {
4420                         let remote_last_secret = self.commitment_secrets.get_secret(self.cur_counterparty_commitment_transaction_number + 2).unwrap();
4421                         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()));
4422                         OptionalField::Present(DataLossProtect {
4423                                 your_last_per_commitment_secret: remote_last_secret,
4424                                 my_current_per_commitment_point: dummy_pubkey
4425                         })
4426                 } else {
4427                         log_info!(logger, "Sending a data_loss_protect with no previous remote per_commitment_secret for channel {}", log_bytes!(self.channel_id()));
4428                         OptionalField::Present(DataLossProtect {
4429                                 your_last_per_commitment_secret: [0;32],
4430                                 my_current_per_commitment_point: dummy_pubkey,
4431                         })
4432                 };
4433                 msgs::ChannelReestablish {
4434                         channel_id: self.channel_id(),
4435                         // The protocol has two different commitment number concepts - the "commitment
4436                         // transaction number", which starts from 0 and counts up, and the "revocation key
4437                         // index" which starts at INITIAL_COMMITMENT_NUMBER and counts down. We track
4438                         // commitment transaction numbers by the index which will be used to reveal the
4439                         // revocation key for that commitment transaction, which means we have to convert them
4440                         // to protocol-level commitment numbers here...
4441
4442                         // next_local_commitment_number is the next commitment_signed number we expect to
4443                         // receive (indicating if they need to resend one that we missed).
4444                         next_local_commitment_number: INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number,
4445                         // We have to set next_remote_commitment_number to the next revoke_and_ack we expect to
4446                         // receive, however we track it by the next commitment number for a remote transaction
4447                         // (which is one further, as they always revoke previous commitment transaction, not
4448                         // the one we send) so we have to decrement by 1. Note that if
4449                         // cur_counterparty_commitment_transaction_number is INITIAL_COMMITMENT_NUMBER we will have
4450                         // dropped this channel on disconnect as it hasn't yet reached FundingSent so we can't
4451                         // overflow here.
4452                         next_remote_commitment_number: INITIAL_COMMITMENT_NUMBER - self.cur_counterparty_commitment_transaction_number - 1,
4453                         data_loss_protect,
4454                 }
4455         }
4456
4457
4458         // Send stuff to our remote peers:
4459
4460         /// Adds a pending outbound HTLC to this channel, note that you probably want
4461         /// send_htlc_and_commit instead cause you'll want both messages at once.
4462         ///
4463         /// This returns an optional UpdateAddHTLC as we may be in a state where we cannot add HTLCs on
4464         /// the wire:
4465         /// * In cases where we're waiting on the remote peer to send us a revoke_and_ack, we
4466         ///   wouldn't be able to determine what they actually ACK'ed if we have two sets of updates
4467         ///   awaiting ACK.
4468         /// * In cases where we're marked MonitorUpdateFailed, we cannot commit to a new state as we
4469         ///   may not yet have sent the previous commitment update messages and will need to regenerate
4470         ///   them.
4471         ///
4472         /// You MUST call send_commitment prior to calling any other methods on this Channel!
4473         ///
4474         /// If an Err is returned, it's a ChannelError::Ignore!
4475         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> {
4476                 if (self.channel_state & (ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK)) != (ChannelState::ChannelFunded as u32) {
4477                         return Err(ChannelError::Ignore("Cannot send HTLC until channel is fully established and we haven't started shutting down".to_owned()));
4478                 }
4479                 let channel_total_msat = self.channel_value_satoshis * 1000;
4480                 if amount_msat > channel_total_msat {
4481                         return Err(ChannelError::Ignore(format!("Cannot send amount {}, because it is more than the total value of the channel {}", amount_msat, channel_total_msat)));
4482                 }
4483
4484                 if amount_msat == 0 {
4485                         return Err(ChannelError::Ignore("Cannot send 0-msat HTLC".to_owned()));
4486                 }
4487
4488                 if amount_msat < self.counterparty_htlc_minimum_msat {
4489                         return Err(ChannelError::Ignore(format!("Cannot send less than their minimum HTLC value ({})", self.counterparty_htlc_minimum_msat)));
4490                 }
4491
4492                 if (self.channel_state & (ChannelState::PeerDisconnected as u32)) != 0 {
4493                         // Note that this should never really happen, if we're !is_live() on receipt of an
4494                         // incoming HTLC for relay will result in us rejecting the HTLC and we won't allow
4495                         // the user to send directly into a !is_live() channel. However, if we
4496                         // disconnected during the time the previous hop was doing the commitment dance we may
4497                         // end up getting here after the forwarding delay. In any case, returning an
4498                         // IgnoreError will get ChannelManager to do the right thing and fail backwards now.
4499                         return Err(ChannelError::Ignore("Cannot send an HTLC while disconnected from channel counterparty".to_owned()));
4500                 }
4501
4502                 let inbound_stats = self.get_inbound_pending_htlc_stats();
4503                 let outbound_stats = self.get_outbound_pending_htlc_stats();
4504                 if outbound_stats.pending_htlcs + 1 > self.counterparty_max_accepted_htlcs as u32 {
4505                         return Err(ChannelError::Ignore(format!("Cannot push more than their max accepted HTLCs ({})", self.counterparty_max_accepted_htlcs)));
4506                 }
4507                 // Check their_max_htlc_value_in_flight_msat
4508                 if outbound_stats.pending_htlcs_value_msat + amount_msat > self.counterparty_max_htlc_value_in_flight_msat {
4509                         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)));
4510                 }
4511
4512                 if !self.is_outbound() {
4513                         // Check that we won't violate the remote channel reserve by adding this HTLC.
4514                         let counterparty_balance_msat = self.channel_value_satoshis * 1000 - self.value_to_self_msat;
4515                         let holder_selected_chan_reserve_msat = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis) * 1000;
4516                         let htlc_candidate = HTLCCandidate::new(amount_msat, HTLCInitiator::LocalOffered);
4517                         let counterparty_commit_tx_fee_msat = self.next_remote_commit_tx_fee_msat(htlc_candidate, None);
4518                         if counterparty_balance_msat < holder_selected_chan_reserve_msat + counterparty_commit_tx_fee_msat {
4519                                 return Err(ChannelError::Ignore("Cannot send value that would put counterparty balance under holder-announced channel reserve value".to_owned()));
4520                         }
4521                 }
4522
4523                 let exposure_dust_limit_success_sats = (self.get_dust_buffer_feerate() as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
4524                 if amount_msat / 1000 < exposure_dust_limit_success_sats {
4525                         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;
4526                         if on_counterparty_dust_htlc_exposure_msat > self.get_max_dust_htlc_exposure_msat() {
4527                                 return Err(ChannelError::Ignore(format!("Cannot send value that would put our exposure to dust HTLCs at {} over the limit {} on counterparty commitment tx",
4528                                         on_counterparty_dust_htlc_exposure_msat, self.get_max_dust_htlc_exposure_msat())));
4529                         }
4530                 }
4531
4532                 let exposure_dust_limit_timeout_sats = (self.get_dust_buffer_feerate() as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
4533                 if amount_msat / 1000 <  exposure_dust_limit_timeout_sats {
4534                         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;
4535                         if on_holder_dust_htlc_exposure_msat > self.get_max_dust_htlc_exposure_msat() {
4536                                 return Err(ChannelError::Ignore(format!("Cannot send value that would put our exposure to dust HTLCs at {} over the limit {} on holder commitment tx",
4537                                         on_holder_dust_htlc_exposure_msat, self.get_max_dust_htlc_exposure_msat())));
4538                         }
4539                 }
4540
4541                 let pending_value_to_self_msat = self.value_to_self_msat - outbound_stats.pending_htlcs_value_msat;
4542                 if pending_value_to_self_msat < amount_msat {
4543                         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)));
4544                 }
4545
4546                 // `2 *` and extra HTLC are for the fee spike buffer.
4547                 let commit_tx_fee_msat = if self.is_outbound() {
4548                         let htlc_candidate = HTLCCandidate::new(amount_msat, HTLCInitiator::LocalOffered);
4549                         FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE * self.next_local_commit_tx_fee_msat(htlc_candidate, Some(()))
4550                 } else { 0 };
4551                 if pending_value_to_self_msat - amount_msat < commit_tx_fee_msat {
4552                         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)));
4553                 }
4554
4555                 // Check self.counterparty_selected_channel_reserve_satoshis (the amount we must keep as
4556                 // reserve for the remote to have something to claim if we misbehave)
4557                 let chan_reserve_msat = self.counterparty_selected_channel_reserve_satoshis.unwrap() * 1000;
4558                 if pending_value_to_self_msat - amount_msat - commit_tx_fee_msat < chan_reserve_msat {
4559                         return Err(ChannelError::Ignore(format!("Cannot send value that would put our balance under counterparty-announced channel reserve value ({})", chan_reserve_msat)));
4560                 }
4561
4562                 // Now update local state:
4563                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
4564                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::AddHTLC {
4565                                 amount_msat,
4566                                 payment_hash,
4567                                 cltv_expiry,
4568                                 source,
4569                                 onion_routing_packet,
4570                         });
4571                         return Ok(None);
4572                 }
4573
4574                 self.pending_outbound_htlcs.push(OutboundHTLCOutput {
4575                         htlc_id: self.next_holder_htlc_id,
4576                         amount_msat,
4577                         payment_hash: payment_hash.clone(),
4578                         cltv_expiry,
4579                         state: OutboundHTLCState::LocalAnnounced(Box::new(onion_routing_packet.clone())),
4580                         source,
4581                 });
4582
4583                 let res = msgs::UpdateAddHTLC {
4584                         channel_id: self.channel_id,
4585                         htlc_id: self.next_holder_htlc_id,
4586                         amount_msat,
4587                         payment_hash,
4588                         cltv_expiry,
4589                         onion_routing_packet,
4590                 };
4591                 self.next_holder_htlc_id += 1;
4592
4593                 Ok(Some(res))
4594         }
4595
4596         /// Creates a signed commitment transaction to send to the remote peer.
4597         /// Always returns a ChannelError::Close if an immediately-preceding (read: the
4598         /// last call to this Channel) send_htlc returned Ok(Some(_)) and there is an Err.
4599         /// May panic if called except immediately after a successful, Ok(Some(_))-returning send_htlc.
4600         pub fn send_commitment<L: Deref>(&mut self, logger: &L) -> Result<(msgs::CommitmentSigned, ChannelMonitorUpdate), ChannelError> where L::Target: Logger {
4601                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
4602                         panic!("Cannot create commitment tx until channel is fully established");
4603                 }
4604                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
4605                         panic!("Cannot create commitment tx until remote revokes their previous commitment");
4606                 }
4607                 if (self.channel_state & (ChannelState::PeerDisconnected as u32)) == (ChannelState::PeerDisconnected as u32) {
4608                         panic!("Cannot create commitment tx while disconnected, as send_htlc will have returned an Err so a send_commitment precondition has been violated");
4609                 }
4610                 if (self.channel_state & (ChannelState::MonitorUpdateFailed as u32)) == (ChannelState::MonitorUpdateFailed as u32) {
4611                         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");
4612                 }
4613                 let mut have_updates = self.is_outbound() && self.pending_update_fee.is_some();
4614                 for htlc in self.pending_outbound_htlcs.iter() {
4615                         if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
4616                                 have_updates = true;
4617                         }
4618                         if have_updates { break; }
4619                 }
4620                 for htlc in self.pending_inbound_htlcs.iter() {
4621                         if let InboundHTLCState::LocalRemoved(_) = htlc.state {
4622                                 have_updates = true;
4623                         }
4624                         if have_updates { break; }
4625                 }
4626                 if !have_updates {
4627                         panic!("Cannot create commitment tx until we have some updates to send");
4628                 }
4629                 self.send_commitment_no_status_check(logger)
4630         }
4631         /// Only fails in case of bad keys
4632         fn send_commitment_no_status_check<L: Deref>(&mut self, logger: &L) -> Result<(msgs::CommitmentSigned, ChannelMonitorUpdate), ChannelError> where L::Target: Logger {
4633                 log_trace!(logger, "Updating HTLC state for a newly-sent commitment_signed...");
4634                 // We can upgrade the status of some HTLCs that are waiting on a commitment, even if we
4635                 // fail to generate this, we still are at least at a position where upgrading their status
4636                 // is acceptable.
4637                 for htlc in self.pending_inbound_htlcs.iter_mut() {
4638                         let new_state = if let &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(ref forward_info) = &htlc.state {
4639                                 Some(InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info.clone()))
4640                         } else { None };
4641                         if let Some(state) = new_state {
4642                                 log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce {} to AwaitingAnnouncedRemoteRevoke", log_bytes!(htlc.payment_hash.0));
4643                                 htlc.state = state;
4644                         }
4645                 }
4646                 for htlc in self.pending_outbound_htlcs.iter_mut() {
4647                         if let Some(fail_reason) = if let &mut OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref mut fail_reason) = &mut htlc.state {
4648                                 Some(fail_reason.take())
4649                         } else { None } {
4650                                 log_trace!(logger, " ...promoting outbound AwaitingRemoteRevokeToRemove {} to AwaitingRemovedRemoteRevoke", log_bytes!(htlc.payment_hash.0));
4651                                 htlc.state = OutboundHTLCState::AwaitingRemovedRemoteRevoke(fail_reason);
4652                         }
4653                 }
4654                 if let Some((feerate, update_state)) = self.pending_update_fee {
4655                         if update_state == FeeUpdateState::AwaitingRemoteRevokeToAnnounce {
4656                                 debug_assert!(!self.is_outbound());
4657                                 log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce fee update {} to Committed", feerate);
4658                                 self.feerate_per_kw = feerate;
4659                                 self.pending_update_fee = None;
4660                         }
4661                 }
4662                 self.resend_order = RAACommitmentOrder::RevokeAndACKFirst;
4663
4664                 let (res, counterparty_commitment_txid, htlcs) = match self.send_commitment_no_state_update(logger) {
4665                         Ok((res, (counterparty_commitment_tx, mut htlcs))) => {
4666                                 // Update state now that we've passed all the can-fail calls...
4667                                 let htlcs_no_ref: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)> =
4668                                         htlcs.drain(..).map(|(htlc, htlc_source)| (htlc, htlc_source.map(|source_ref| Box::new(source_ref.clone())))).collect();
4669                                 (res, counterparty_commitment_tx, htlcs_no_ref)
4670                         },
4671                         Err(e) => return Err(e),
4672                 };
4673
4674                 self.latest_monitor_update_id += 1;
4675                 let monitor_update = ChannelMonitorUpdate {
4676                         update_id: self.latest_monitor_update_id,
4677                         updates: vec![ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo {
4678                                 commitment_txid: counterparty_commitment_txid,
4679                                 htlc_outputs: htlcs.clone(),
4680                                 commitment_number: self.cur_counterparty_commitment_transaction_number,
4681                                 their_revocation_point: self.counterparty_cur_commitment_point.unwrap()
4682                         }]
4683                 };
4684                 self.channel_state |= ChannelState::AwaitingRemoteRevoke as u32;
4685                 Ok((res, monitor_update))
4686         }
4687
4688         /// Only fails in case of bad keys. Used for channel_reestablish commitment_signed generation
4689         /// when we shouldn't change HTLC/channel state.
4690         fn send_commitment_no_state_update<L: Deref>(&self, logger: &L) -> Result<(msgs::CommitmentSigned, (Txid, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>)), ChannelError> where L::Target: Logger {
4691                 let counterparty_keys = self.build_remote_transaction_keys()?;
4692                 let counterparty_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, true, logger);
4693                 let feerate_per_kw = counterparty_commitment_tx.1;
4694                 let counterparty_commitment_txid = counterparty_commitment_tx.0.trust().txid();
4695                 let (signature, htlc_signatures);
4696
4697                 #[cfg(any(test, feature = "fuzztarget"))]
4698                 {
4699                         if !self.is_outbound() {
4700                                 let projected_commit_tx_info = self.next_remote_commitment_tx_fee_info_cached.lock().unwrap().take();
4701                                 *self.next_local_commitment_tx_fee_info_cached.lock().unwrap() = None;
4702                                 if let Some(info) = projected_commit_tx_info {
4703                                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len();
4704                                         if info.total_pending_htlcs == total_pending_htlcs
4705                                                 && info.next_holder_htlc_id == self.next_holder_htlc_id
4706                                                 && info.next_counterparty_htlc_id == self.next_counterparty_htlc_id
4707                                                 && info.feerate == self.feerate_per_kw {
4708                                                         let actual_fee = self.commit_tx_fee_msat(counterparty_commitment_tx.2);
4709                                                         assert_eq!(actual_fee, info.fee);
4710                                                 }
4711                                 }
4712                         }
4713                 }
4714
4715                 {
4716                         let mut htlcs = Vec::with_capacity(counterparty_commitment_tx.3.len());
4717                         for &(ref htlc, _) in counterparty_commitment_tx.3.iter() {
4718                                 htlcs.push(htlc);
4719                         }
4720
4721                         let res = self.holder_signer.sign_counterparty_commitment(&counterparty_commitment_tx.0, &self.secp_ctx)
4722                                 .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?;
4723                         signature = res.0;
4724                         htlc_signatures = res.1;
4725
4726                         log_trace!(logger, "Signed remote commitment tx {} (txid {}) with redeemscript {} -> {} in channel {}",
4727                                 encode::serialize_hex(&counterparty_commitment_tx.0.trust().built_transaction().transaction),
4728                                 &counterparty_commitment_txid, encode::serialize_hex(&self.get_funding_redeemscript()),
4729                                 log_bytes!(signature.serialize_compact()[..]), log_bytes!(self.channel_id()));
4730
4731                         for (ref htlc_sig, ref htlc) in htlc_signatures.iter().zip(htlcs) {
4732                                 log_trace!(logger, "Signed remote HTLC tx {} with redeemscript {} with pubkey {} -> {} in channel {}",
4733                                         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)),
4734                                         encode::serialize_hex(&chan_utils::get_htlc_redeemscript(&htlc, &counterparty_keys)),
4735                                         log_bytes!(counterparty_keys.broadcaster_htlc_key.serialize()),
4736                                         log_bytes!(htlc_sig.serialize_compact()[..]), log_bytes!(self.channel_id()));
4737                         }
4738                 }
4739
4740                 Ok((msgs::CommitmentSigned {
4741                         channel_id: self.channel_id,
4742                         signature,
4743                         htlc_signatures,
4744                 }, (counterparty_commitment_txid, counterparty_commitment_tx.3)))
4745         }
4746
4747         /// Adds a pending outbound HTLC to this channel, and creates a signed commitment transaction
4748         /// to send to the remote peer in one go.
4749         /// Shorthand for calling send_htlc() followed by send_commitment(), see docs on those for
4750         /// more info.
4751         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 {
4752                 match self.send_htlc(amount_msat, payment_hash, cltv_expiry, source, onion_routing_packet)? {
4753                         Some(update_add_htlc) => {
4754                                 let (commitment_signed, monitor_update) = self.send_commitment_no_status_check(logger)?;
4755                                 Ok(Some((update_add_htlc, commitment_signed, monitor_update)))
4756                         },
4757                         None => Ok(None)
4758                 }
4759         }
4760
4761         /// Get forwarding information for the counterparty.
4762         pub fn counterparty_forwarding_info(&self) -> Option<CounterpartyForwardingInfo> {
4763                 self.counterparty_forwarding_info.clone()
4764         }
4765
4766         pub fn channel_update(&mut self, msg: &msgs::ChannelUpdate) -> Result<(), ChannelError> {
4767                 if msg.contents.htlc_minimum_msat >= self.channel_value_satoshis * 1000 {
4768                         return Err(ChannelError::Close("Minimum htlc value is greater than channel value".to_string()));
4769                 }
4770                 self.counterparty_forwarding_info = Some(CounterpartyForwardingInfo {
4771                         fee_base_msat: msg.contents.fee_base_msat,
4772                         fee_proportional_millionths: msg.contents.fee_proportional_millionths,
4773                         cltv_expiry_delta: msg.contents.cltv_expiry_delta
4774                 });
4775
4776                 Ok(())
4777         }
4778
4779         /// Begins the shutdown process, getting a message for the remote peer and returning all
4780         /// holding cell HTLCs for payment failure.
4781         pub fn get_shutdown<K: Deref>(&mut self, keys_provider: &K, their_features: &InitFeatures, target_feerate_sats_per_kw: Option<u32>)
4782         -> Result<(msgs::Shutdown, Option<ChannelMonitorUpdate>, Vec<(HTLCSource, PaymentHash)>), APIError>
4783         where K::Target: KeysInterface<Signer = Signer> {
4784                 for htlc in self.pending_outbound_htlcs.iter() {
4785                         if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
4786                                 return Err(APIError::APIMisuseError{err: "Cannot begin shutdown with pending HTLCs. Process pending events first".to_owned()});
4787                         }
4788                 }
4789                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != 0 {
4790                         if (self.channel_state & ChannelState::LocalShutdownSent as u32) == ChannelState::LocalShutdownSent as u32 {
4791                                 return Err(APIError::APIMisuseError{err: "Shutdown already in progress".to_owned()});
4792                         }
4793                         else if (self.channel_state & ChannelState::RemoteShutdownSent as u32) == ChannelState::RemoteShutdownSent as u32 {
4794                                 return Err(APIError::ChannelUnavailable{err: "Shutdown already in progress by remote".to_owned()});
4795                         }
4796                 }
4797                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
4798                 if self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32) != 0 {
4799                         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()});
4800                 }
4801
4802                 let update_shutdown_script = match self.shutdown_scriptpubkey {
4803                         Some(_) => false,
4804                         None => {
4805                                 let shutdown_scriptpubkey = keys_provider.get_shutdown_scriptpubkey();
4806                                 if !shutdown_scriptpubkey.is_compatible(their_features) {
4807                                         return Err(APIError::IncompatibleShutdownScript { script: shutdown_scriptpubkey.clone() });
4808                                 }
4809                                 self.shutdown_scriptpubkey = Some(shutdown_scriptpubkey);
4810                                 true
4811                         },
4812                 };
4813
4814                 // From here on out, we may not fail!
4815                 self.target_closing_feerate_sats_per_kw = target_feerate_sats_per_kw;
4816                 if self.channel_state < ChannelState::FundingSent as u32 {
4817                         self.channel_state = ChannelState::ShutdownComplete as u32;
4818                 } else {
4819                         self.channel_state |= ChannelState::LocalShutdownSent as u32;
4820                 }
4821                 self.update_time_counter += 1;
4822
4823                 let monitor_update = if update_shutdown_script {
4824                         self.latest_monitor_update_id += 1;
4825                         Some(ChannelMonitorUpdate {
4826                                 update_id: self.latest_monitor_update_id,
4827                                 updates: vec![ChannelMonitorUpdateStep::ShutdownScript {
4828                                         scriptpubkey: self.get_closing_scriptpubkey(),
4829                                 }],
4830                         })
4831                 } else { None };
4832                 let shutdown = msgs::Shutdown {
4833                         channel_id: self.channel_id,
4834                         scriptpubkey: self.get_closing_scriptpubkey(),
4835                 };
4836
4837                 // Go ahead and drop holding cell updates as we'd rather fail payments than wait to send
4838                 // our shutdown until we've committed all of the pending changes.
4839                 self.holding_cell_update_fee = None;
4840                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
4841                 self.holding_cell_htlc_updates.retain(|htlc_update| {
4842                         match htlc_update {
4843                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
4844                                         dropped_outbound_htlcs.push((source.clone(), payment_hash.clone()));
4845                                         false
4846                                 },
4847                                 _ => true
4848                         }
4849                 });
4850
4851                 Ok((shutdown, monitor_update, dropped_outbound_htlcs))
4852         }
4853
4854         /// Gets the latest commitment transaction and any dependent transactions for relay (forcing
4855         /// shutdown of this channel - no more calls into this Channel may be made afterwards except
4856         /// those explicitly stated to be allowed after shutdown completes, eg some simple getters).
4857         /// Also returns the list of payment_hashes for channels which we can safely fail backwards
4858         /// immediately (others we will have to allow to time out).
4859         pub fn force_shutdown(&mut self, should_broadcast: bool) -> (Option<(OutPoint, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>) {
4860                 // Note that we MUST only generate a monitor update that indicates force-closure - we're
4861                 // called during initialization prior to the chain_monitor in the encompassing ChannelManager
4862                 // being fully configured in some cases. Thus, its likely any monitor events we generate will
4863                 // be delayed in being processed! See the docs for `ChannelManagerReadArgs` for more.
4864                 assert!(self.channel_state != ChannelState::ShutdownComplete as u32);
4865
4866                 // We go ahead and "free" any holding cell HTLCs or HTLCs we haven't yet committed to and
4867                 // return them to fail the payment.
4868                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
4869                 for htlc_update in self.holding_cell_htlc_updates.drain(..) {
4870                         match htlc_update {
4871                                 HTLCUpdateAwaitingACK::AddHTLC { source, payment_hash, .. } => {
4872                                         dropped_outbound_htlcs.push((source, payment_hash));
4873                                 },
4874                                 _ => {}
4875                         }
4876                 }
4877                 let monitor_update = if let Some(funding_txo) = self.get_funding_txo() {
4878                         // If we haven't yet exchanged funding signatures (ie channel_state < FundingSent),
4879                         // returning a channel monitor update here would imply a channel monitor update before
4880                         // we even registered the channel monitor to begin with, which is invalid.
4881                         // Thus, if we aren't actually at a point where we could conceivably broadcast the
4882                         // funding transaction, don't return a funding txo (which prevents providing the
4883                         // monitor update to the user, even if we return one).
4884                         // See test_duplicate_chan_id and test_pre_lockin_no_chan_closed_update for more.
4885                         if self.channel_state & (ChannelState::FundingSent as u32 | ChannelState::ChannelFunded as u32 | ChannelState::ShutdownComplete as u32) != 0 {
4886                                 self.latest_monitor_update_id += 1;
4887                                 Some((funding_txo, ChannelMonitorUpdate {
4888                                         update_id: self.latest_monitor_update_id,
4889                                         updates: vec![ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast }],
4890                                 }))
4891                         } else { None }
4892                 } else { None };
4893
4894                 self.channel_state = ChannelState::ShutdownComplete as u32;
4895                 self.update_time_counter += 1;
4896                 (monitor_update, dropped_outbound_htlcs)
4897         }
4898 }
4899
4900 const SERIALIZATION_VERSION: u8 = 2;
4901 const MIN_SERIALIZATION_VERSION: u8 = 1;
4902
4903 impl_writeable_tlv_based_enum!(InboundHTLCRemovalReason,;
4904         (0, FailRelay),
4905         (1, FailMalformed),
4906         (2, Fulfill),
4907 );
4908
4909 impl Writeable for ChannelUpdateStatus {
4910         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
4911                 // We only care about writing out the current state as it was announced, ie only either
4912                 // Enabled or Disabled. In the case of DisabledStaged, we most recently announced the
4913                 // channel as enabled, so we write 0. For EnabledStaged, we similarly write a 1.
4914                 match self {
4915                         ChannelUpdateStatus::Enabled => 0u8.write(writer)?,
4916                         ChannelUpdateStatus::DisabledStaged => 0u8.write(writer)?,
4917                         ChannelUpdateStatus::EnabledStaged => 1u8.write(writer)?,
4918                         ChannelUpdateStatus::Disabled => 1u8.write(writer)?,
4919                 }
4920                 Ok(())
4921         }
4922 }
4923
4924 impl Readable for ChannelUpdateStatus {
4925         fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
4926                 Ok(match <u8 as Readable>::read(reader)? {
4927                         0 => ChannelUpdateStatus::Enabled,
4928                         1 => ChannelUpdateStatus::Disabled,
4929                         _ => return Err(DecodeError::InvalidValue),
4930                 })
4931         }
4932 }
4933
4934 impl<Signer: Sign> Writeable for Channel<Signer> {
4935         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
4936                 // Note that we write out as if remove_uncommitted_htlcs_and_mark_paused had just been
4937                 // called.
4938
4939                 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
4940
4941                 self.user_id.write(writer)?;
4942
4943                 // Write out the old serialization for the config object. This is read by version-1
4944                 // deserializers, but we will read the version in the TLV at the end instead.
4945                 self.config.forwarding_fee_proportional_millionths.write(writer)?;
4946                 self.config.cltv_expiry_delta.write(writer)?;
4947                 self.config.announced_channel.write(writer)?;
4948                 self.config.commit_upfront_shutdown_pubkey.write(writer)?;
4949
4950                 self.channel_id.write(writer)?;
4951                 (self.channel_state | ChannelState::PeerDisconnected as u32).write(writer)?;
4952                 self.channel_value_satoshis.write(writer)?;
4953
4954                 self.latest_monitor_update_id.write(writer)?;
4955
4956                 let mut key_data = VecWriter(Vec::new());
4957                 self.holder_signer.write(&mut key_data)?;
4958                 assert!(key_data.0.len() < core::usize::MAX);
4959                 assert!(key_data.0.len() < core::u32::MAX as usize);
4960                 (key_data.0.len() as u32).write(writer)?;
4961                 writer.write_all(&key_data.0[..])?;
4962
4963                 // Write out the old serialization for shutdown_pubkey for backwards compatibility, if
4964                 // deserialized from that format.
4965                 match self.shutdown_scriptpubkey.as_ref().and_then(|script| script.as_legacy_pubkey()) {
4966                         Some(shutdown_pubkey) => shutdown_pubkey.write(writer)?,
4967                         None => [0u8; PUBLIC_KEY_SIZE].write(writer)?,
4968                 }
4969                 self.destination_script.write(writer)?;
4970
4971                 self.cur_holder_commitment_transaction_number.write(writer)?;
4972                 self.cur_counterparty_commitment_transaction_number.write(writer)?;
4973                 self.value_to_self_msat.write(writer)?;
4974
4975                 let mut dropped_inbound_htlcs = 0;
4976                 for htlc in self.pending_inbound_htlcs.iter() {
4977                         if let InboundHTLCState::RemoteAnnounced(_) = htlc.state {
4978                                 dropped_inbound_htlcs += 1;
4979                         }
4980                 }
4981                 (self.pending_inbound_htlcs.len() as u64 - dropped_inbound_htlcs).write(writer)?;
4982                 for htlc in self.pending_inbound_htlcs.iter() {
4983                         if let &InboundHTLCState::RemoteAnnounced(_) = &htlc.state {
4984                                 continue; // Drop
4985                         }
4986                         htlc.htlc_id.write(writer)?;
4987                         htlc.amount_msat.write(writer)?;
4988                         htlc.cltv_expiry.write(writer)?;
4989                         htlc.payment_hash.write(writer)?;
4990                         match &htlc.state {
4991                                 &InboundHTLCState::RemoteAnnounced(_) => unreachable!(),
4992                                 &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(ref htlc_state) => {
4993                                         1u8.write(writer)?;
4994                                         htlc_state.write(writer)?;
4995                                 },
4996                                 &InboundHTLCState::AwaitingAnnouncedRemoteRevoke(ref htlc_state) => {
4997                                         2u8.write(writer)?;
4998                                         htlc_state.write(writer)?;
4999                                 },
5000                                 &InboundHTLCState::Committed => {
5001                                         3u8.write(writer)?;
5002                                 },
5003                                 &InboundHTLCState::LocalRemoved(ref removal_reason) => {
5004                                         4u8.write(writer)?;
5005                                         removal_reason.write(writer)?;
5006                                 },
5007                         }
5008                 }
5009
5010                 (self.pending_outbound_htlcs.len() as u64).write(writer)?;
5011                 for htlc in self.pending_outbound_htlcs.iter() {
5012                         htlc.htlc_id.write(writer)?;
5013                         htlc.amount_msat.write(writer)?;
5014                         htlc.cltv_expiry.write(writer)?;
5015                         htlc.payment_hash.write(writer)?;
5016                         htlc.source.write(writer)?;
5017                         match &htlc.state {
5018                                 &OutboundHTLCState::LocalAnnounced(ref onion_packet) => {
5019                                         0u8.write(writer)?;
5020                                         onion_packet.write(writer)?;
5021                                 },
5022                                 &OutboundHTLCState::Committed => {
5023                                         1u8.write(writer)?;
5024                                 },
5025                                 &OutboundHTLCState::RemoteRemoved(_) => {
5026                                         // Treat this as a Committed because we haven't received the CS - they'll
5027                                         // resend the claim/fail on reconnect as we all (hopefully) the missing CS.
5028                                         1u8.write(writer)?;
5029                                 },
5030                                 &OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref fail_reason) => {
5031                                         3u8.write(writer)?;
5032                                         fail_reason.write(writer)?;
5033                                 },
5034                                 &OutboundHTLCState::AwaitingRemovedRemoteRevoke(ref fail_reason) => {
5035                                         4u8.write(writer)?;
5036                                         fail_reason.write(writer)?;
5037                                 },
5038                         }
5039                 }
5040
5041                 (self.holding_cell_htlc_updates.len() as u64).write(writer)?;
5042                 for update in self.holding_cell_htlc_updates.iter() {
5043                         match update {
5044                                 &HTLCUpdateAwaitingACK::AddHTLC { ref amount_msat, ref cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet } => {
5045                                         0u8.write(writer)?;
5046                                         amount_msat.write(writer)?;
5047                                         cltv_expiry.write(writer)?;
5048                                         payment_hash.write(writer)?;
5049                                         source.write(writer)?;
5050                                         onion_routing_packet.write(writer)?;
5051                                 },
5052                                 &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, ref htlc_id } => {
5053                                         1u8.write(writer)?;
5054                                         payment_preimage.write(writer)?;
5055                                         htlc_id.write(writer)?;
5056                                 },
5057                                 &HTLCUpdateAwaitingACK::FailHTLC { ref htlc_id, ref err_packet } => {
5058                                         2u8.write(writer)?;
5059                                         htlc_id.write(writer)?;
5060                                         err_packet.write(writer)?;
5061                                 }
5062                         }
5063                 }
5064
5065                 match self.resend_order {
5066                         RAACommitmentOrder::CommitmentFirst => 0u8.write(writer)?,
5067                         RAACommitmentOrder::RevokeAndACKFirst => 1u8.write(writer)?,
5068                 }
5069
5070                 self.monitor_pending_funding_locked.write(writer)?;
5071                 self.monitor_pending_revoke_and_ack.write(writer)?;
5072                 self.monitor_pending_commitment_signed.write(writer)?;
5073
5074                 (self.monitor_pending_forwards.len() as u64).write(writer)?;
5075                 for &(ref pending_forward, ref htlc_id) in self.monitor_pending_forwards.iter() {
5076                         pending_forward.write(writer)?;
5077                         htlc_id.write(writer)?;
5078                 }
5079
5080                 (self.monitor_pending_failures.len() as u64).write(writer)?;
5081                 for &(ref htlc_source, ref payment_hash, ref fail_reason) in self.monitor_pending_failures.iter() {
5082                         htlc_source.write(writer)?;
5083                         payment_hash.write(writer)?;
5084                         fail_reason.write(writer)?;
5085                 }
5086
5087                 if self.is_outbound() {
5088                         self.pending_update_fee.map(|(a, _)| a).write(writer)?;
5089                 } else if let Some((feerate, FeeUpdateState::AwaitingRemoteRevokeToAnnounce)) = self.pending_update_fee {
5090                         Some(feerate).write(writer)?;
5091                 } else {
5092                         // As for inbound HTLCs, if the update was only announced and never committed in a
5093                         // commitment_signed, drop it.
5094                         None::<u32>.write(writer)?;
5095                 }
5096                 self.holding_cell_update_fee.write(writer)?;
5097
5098                 self.next_holder_htlc_id.write(writer)?;
5099                 (self.next_counterparty_htlc_id - dropped_inbound_htlcs).write(writer)?;
5100                 self.update_time_counter.write(writer)?;
5101                 self.feerate_per_kw.write(writer)?;
5102
5103                 // Versions prior to 0.0.100 expected to read the fields of `last_sent_closing_fee` here,
5104                 // however we are supposed to restart shutdown fee negotiation on reconnect (and wipe
5105                 // `last_send_closing_fee` in `remove_uncommitted_htlcs_and_mark_paused`) so we should never
5106                 // consider the stale state on reload.
5107                 0u8.write(writer)?;
5108
5109                 self.funding_tx_confirmed_in.write(writer)?;
5110                 self.funding_tx_confirmation_height.write(writer)?;
5111                 self.short_channel_id.write(writer)?;
5112
5113                 self.counterparty_dust_limit_satoshis.write(writer)?;
5114                 self.holder_dust_limit_satoshis.write(writer)?;
5115                 self.counterparty_max_htlc_value_in_flight_msat.write(writer)?;
5116
5117                 // Note that this field is ignored by 0.0.99+ as the TLV Optional variant is used instead.
5118                 self.counterparty_selected_channel_reserve_satoshis.unwrap_or(0).write(writer)?;
5119
5120                 self.counterparty_htlc_minimum_msat.write(writer)?;
5121                 self.holder_htlc_minimum_msat.write(writer)?;
5122                 self.counterparty_max_accepted_htlcs.write(writer)?;
5123
5124                 // Note that this field is ignored by 0.0.99+ as the TLV Optional variant is used instead.
5125                 self.minimum_depth.unwrap_or(0).write(writer)?;
5126
5127                 match &self.counterparty_forwarding_info {
5128                         Some(info) => {
5129                                 1u8.write(writer)?;
5130                                 info.fee_base_msat.write(writer)?;
5131                                 info.fee_proportional_millionths.write(writer)?;
5132                                 info.cltv_expiry_delta.write(writer)?;
5133                         },
5134                         None => 0u8.write(writer)?
5135                 }
5136
5137                 self.channel_transaction_parameters.write(writer)?;
5138                 self.funding_transaction.write(writer)?;
5139
5140                 self.counterparty_cur_commitment_point.write(writer)?;
5141                 self.counterparty_prev_commitment_point.write(writer)?;
5142                 self.counterparty_node_id.write(writer)?;
5143
5144                 self.counterparty_shutdown_scriptpubkey.write(writer)?;
5145
5146                 self.commitment_secrets.write(writer)?;
5147
5148                 self.channel_update_status.write(writer)?;
5149
5150                 #[cfg(any(test, feature = "fuzztarget"))]
5151                 (self.historical_inbound_htlc_fulfills.len() as u64).write(writer)?;
5152                 #[cfg(any(test, feature = "fuzztarget"))]
5153                 for htlc in self.historical_inbound_htlc_fulfills.iter() {
5154                         htlc.write(writer)?;
5155                 }
5156
5157                 write_tlv_fields!(writer, {
5158                         (0, self.announcement_sigs, option),
5159                         // minimum_depth and counterparty_selected_channel_reserve_satoshis used to have a
5160                         // default value instead of being Option<>al. Thus, to maintain compatibility we write
5161                         // them twice, once with their original default values above, and once as an option
5162                         // here. On the read side, old versions will simply ignore the odd-type entries here,
5163                         // and new versions map the default values to None and allow the TLV entries here to
5164                         // override that.
5165                         (1, self.minimum_depth, option),
5166                         (3, self.counterparty_selected_channel_reserve_satoshis, option),
5167                         (5, self.config, required),
5168                         (7, self.shutdown_scriptpubkey, option),
5169                         (9, self.target_closing_feerate_sats_per_kw, option),
5170                 });
5171
5172                 Ok(())
5173         }
5174 }
5175
5176 const MAX_ALLOC_SIZE: usize = 64*1024;
5177 impl<'a, Signer: Sign, K: Deref> ReadableArgs<&'a K> for Channel<Signer>
5178                 where K::Target: KeysInterface<Signer = Signer> {
5179         fn read<R : io::Read>(reader: &mut R, keys_source: &'a K) -> Result<Self, DecodeError> {
5180                 let ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
5181
5182                 let user_id = Readable::read(reader)?;
5183
5184                 let mut config = Some(ChannelConfig::default());
5185                 if ver == 1 {
5186                         // Read the old serialization of the ChannelConfig from version 0.0.98.
5187                         config.as_mut().unwrap().forwarding_fee_proportional_millionths = Readable::read(reader)?;
5188                         config.as_mut().unwrap().cltv_expiry_delta = Readable::read(reader)?;
5189                         config.as_mut().unwrap().announced_channel = Readable::read(reader)?;
5190                         config.as_mut().unwrap().commit_upfront_shutdown_pubkey = Readable::read(reader)?;
5191                 } else {
5192                         // Read the 8 bytes of backwards-compatibility ChannelConfig data.
5193                         let mut _val: u64 = Readable::read(reader)?;
5194                 }
5195
5196                 let channel_id = Readable::read(reader)?;
5197                 let channel_state = Readable::read(reader)?;
5198                 let channel_value_satoshis = Readable::read(reader)?;
5199
5200                 let latest_monitor_update_id = Readable::read(reader)?;
5201
5202                 let keys_len: u32 = Readable::read(reader)?;
5203                 let mut keys_data = Vec::with_capacity(cmp::min(keys_len as usize, MAX_ALLOC_SIZE));
5204                 while keys_data.len() != keys_len as usize {
5205                         // Read 1KB at a time to avoid accidentally allocating 4GB on corrupted channel keys
5206                         let mut data = [0; 1024];
5207                         let read_slice = &mut data[0..cmp::min(1024, keys_len as usize - keys_data.len())];
5208                         reader.read_exact(read_slice)?;
5209                         keys_data.extend_from_slice(read_slice);
5210                 }
5211                 let holder_signer = keys_source.read_chan_signer(&keys_data)?;
5212
5213                 // Read the old serialization for shutdown_pubkey, preferring the TLV field later if set.
5214                 let mut shutdown_scriptpubkey = match <PublicKey as Readable>::read(reader) {
5215                         Ok(pubkey) => Some(ShutdownScript::new_p2wpkh_from_pubkey(pubkey)),
5216                         Err(_) => None,
5217                 };
5218                 let destination_script = Readable::read(reader)?;
5219
5220                 let cur_holder_commitment_transaction_number = Readable::read(reader)?;
5221                 let cur_counterparty_commitment_transaction_number = Readable::read(reader)?;
5222                 let value_to_self_msat = Readable::read(reader)?;
5223
5224                 let pending_inbound_htlc_count: u64 = Readable::read(reader)?;
5225                 let mut pending_inbound_htlcs = Vec::with_capacity(cmp::min(pending_inbound_htlc_count as usize, OUR_MAX_HTLCS as usize));
5226                 for _ in 0..pending_inbound_htlc_count {
5227                         pending_inbound_htlcs.push(InboundHTLCOutput {
5228                                 htlc_id: Readable::read(reader)?,
5229                                 amount_msat: Readable::read(reader)?,
5230                                 cltv_expiry: Readable::read(reader)?,
5231                                 payment_hash: Readable::read(reader)?,
5232                                 state: match <u8 as Readable>::read(reader)? {
5233                                         1 => InboundHTLCState::AwaitingRemoteRevokeToAnnounce(Readable::read(reader)?),
5234                                         2 => InboundHTLCState::AwaitingAnnouncedRemoteRevoke(Readable::read(reader)?),
5235                                         3 => InboundHTLCState::Committed,
5236                                         4 => InboundHTLCState::LocalRemoved(Readable::read(reader)?),
5237                                         _ => return Err(DecodeError::InvalidValue),
5238                                 },
5239                         });
5240                 }
5241
5242                 let pending_outbound_htlc_count: u64 = Readable::read(reader)?;
5243                 let mut pending_outbound_htlcs = Vec::with_capacity(cmp::min(pending_outbound_htlc_count as usize, OUR_MAX_HTLCS as usize));
5244                 for _ in 0..pending_outbound_htlc_count {
5245                         pending_outbound_htlcs.push(OutboundHTLCOutput {
5246                                 htlc_id: Readable::read(reader)?,
5247                                 amount_msat: Readable::read(reader)?,
5248                                 cltv_expiry: Readable::read(reader)?,
5249                                 payment_hash: Readable::read(reader)?,
5250                                 source: Readable::read(reader)?,
5251                                 state: match <u8 as Readable>::read(reader)? {
5252                                         0 => OutboundHTLCState::LocalAnnounced(Box::new(Readable::read(reader)?)),
5253                                         1 => OutboundHTLCState::Committed,
5254                                         2 => OutboundHTLCState::RemoteRemoved(Readable::read(reader)?),
5255                                         3 => OutboundHTLCState::AwaitingRemoteRevokeToRemove(Readable::read(reader)?),
5256                                         4 => OutboundHTLCState::AwaitingRemovedRemoteRevoke(Readable::read(reader)?),
5257                                         _ => return Err(DecodeError::InvalidValue),
5258                                 },
5259                         });
5260                 }
5261
5262                 let holding_cell_htlc_update_count: u64 = Readable::read(reader)?;
5263                 let mut holding_cell_htlc_updates = Vec::with_capacity(cmp::min(holding_cell_htlc_update_count as usize, OUR_MAX_HTLCS as usize*2));
5264                 for _ in 0..holding_cell_htlc_update_count {
5265                         holding_cell_htlc_updates.push(match <u8 as Readable>::read(reader)? {
5266                                 0 => HTLCUpdateAwaitingACK::AddHTLC {
5267                                         amount_msat: Readable::read(reader)?,
5268                                         cltv_expiry: Readable::read(reader)?,
5269                                         payment_hash: Readable::read(reader)?,
5270                                         source: Readable::read(reader)?,
5271                                         onion_routing_packet: Readable::read(reader)?,
5272                                 },
5273                                 1 => HTLCUpdateAwaitingACK::ClaimHTLC {
5274                                         payment_preimage: Readable::read(reader)?,
5275                                         htlc_id: Readable::read(reader)?,
5276                                 },
5277                                 2 => HTLCUpdateAwaitingACK::FailHTLC {
5278                                         htlc_id: Readable::read(reader)?,
5279                                         err_packet: Readable::read(reader)?,
5280                                 },
5281                                 _ => return Err(DecodeError::InvalidValue),
5282                         });
5283                 }
5284
5285                 let resend_order = match <u8 as Readable>::read(reader)? {
5286                         0 => RAACommitmentOrder::CommitmentFirst,
5287                         1 => RAACommitmentOrder::RevokeAndACKFirst,
5288                         _ => return Err(DecodeError::InvalidValue),
5289                 };
5290
5291                 let monitor_pending_funding_locked = Readable::read(reader)?;
5292                 let monitor_pending_revoke_and_ack = Readable::read(reader)?;
5293                 let monitor_pending_commitment_signed = Readable::read(reader)?;
5294
5295                 let monitor_pending_forwards_count: u64 = Readable::read(reader)?;
5296                 let mut monitor_pending_forwards = Vec::with_capacity(cmp::min(monitor_pending_forwards_count as usize, OUR_MAX_HTLCS as usize));
5297                 for _ in 0..monitor_pending_forwards_count {
5298                         monitor_pending_forwards.push((Readable::read(reader)?, Readable::read(reader)?));
5299                 }
5300
5301                 let monitor_pending_failures_count: u64 = Readable::read(reader)?;
5302                 let mut monitor_pending_failures = Vec::with_capacity(cmp::min(monitor_pending_failures_count as usize, OUR_MAX_HTLCS as usize));
5303                 for _ in 0..monitor_pending_failures_count {
5304                         monitor_pending_failures.push((Readable::read(reader)?, Readable::read(reader)?, Readable::read(reader)?));
5305                 }
5306
5307                 let pending_update_fee_value: Option<u32> = Readable::read(reader)?;
5308
5309                 let holding_cell_update_fee = Readable::read(reader)?;
5310
5311                 let next_holder_htlc_id = Readable::read(reader)?;
5312                 let next_counterparty_htlc_id = Readable::read(reader)?;
5313                 let update_time_counter = Readable::read(reader)?;
5314                 let feerate_per_kw = Readable::read(reader)?;
5315
5316                 // Versions prior to 0.0.100 expected to read the fields of `last_sent_closing_fee` here,
5317                 // however we are supposed to restart shutdown fee negotiation on reconnect (and wipe
5318                 // `last_send_closing_fee` in `remove_uncommitted_htlcs_and_mark_paused`) so we should never
5319                 // consider the stale state on reload.
5320                 match <u8 as Readable>::read(reader)? {
5321                         0 => {},
5322                         1 => {
5323                                 let _: u32 = Readable::read(reader)?;
5324                                 let _: u64 = Readable::read(reader)?;
5325                                 let _: Signature = Readable::read(reader)?;
5326                         },
5327                         _ => return Err(DecodeError::InvalidValue),
5328                 }
5329
5330                 let funding_tx_confirmed_in = Readable::read(reader)?;
5331                 let funding_tx_confirmation_height = Readable::read(reader)?;
5332                 let short_channel_id = Readable::read(reader)?;
5333
5334                 let counterparty_dust_limit_satoshis = Readable::read(reader)?;
5335                 let holder_dust_limit_satoshis = Readable::read(reader)?;
5336                 let counterparty_max_htlc_value_in_flight_msat = Readable::read(reader)?;
5337                 let mut counterparty_selected_channel_reserve_satoshis = None;
5338                 if ver == 1 {
5339                         // Read the old serialization from version 0.0.98.
5340                         counterparty_selected_channel_reserve_satoshis = Some(Readable::read(reader)?);
5341                 } else {
5342                         // Read the 8 bytes of backwards-compatibility data.
5343                         let _dummy: u64 = Readable::read(reader)?;
5344                 }
5345                 let counterparty_htlc_minimum_msat = Readable::read(reader)?;
5346                 let holder_htlc_minimum_msat = Readable::read(reader)?;
5347                 let counterparty_max_accepted_htlcs = Readable::read(reader)?;
5348
5349                 let mut minimum_depth = None;
5350                 if ver == 1 {
5351                         // Read the old serialization from version 0.0.98.
5352                         minimum_depth = Some(Readable::read(reader)?);
5353                 } else {
5354                         // Read the 4 bytes of backwards-compatibility data.
5355                         let _dummy: u32 = Readable::read(reader)?;
5356                 }
5357
5358                 let counterparty_forwarding_info = match <u8 as Readable>::read(reader)? {
5359                         0 => None,
5360                         1 => Some(CounterpartyForwardingInfo {
5361                                 fee_base_msat: Readable::read(reader)?,
5362                                 fee_proportional_millionths: Readable::read(reader)?,
5363                                 cltv_expiry_delta: Readable::read(reader)?,
5364                         }),
5365                         _ => return Err(DecodeError::InvalidValue),
5366                 };
5367
5368                 let channel_parameters: ChannelTransactionParameters = Readable::read(reader)?;
5369                 let funding_transaction = Readable::read(reader)?;
5370
5371                 let counterparty_cur_commitment_point = Readable::read(reader)?;
5372
5373                 let counterparty_prev_commitment_point = Readable::read(reader)?;
5374                 let counterparty_node_id = Readable::read(reader)?;
5375
5376                 let counterparty_shutdown_scriptpubkey = Readable::read(reader)?;
5377                 let commitment_secrets = Readable::read(reader)?;
5378
5379                 let channel_update_status = Readable::read(reader)?;
5380
5381                 #[cfg(any(test, feature = "fuzztarget"))]
5382                 let mut historical_inbound_htlc_fulfills = HashSet::new();
5383                 #[cfg(any(test, feature = "fuzztarget"))]
5384                 {
5385                         let htlc_fulfills_len: u64 = Readable::read(reader)?;
5386                         for _ in 0..htlc_fulfills_len {
5387                                 assert!(historical_inbound_htlc_fulfills.insert(Readable::read(reader)?));
5388                         }
5389                 }
5390
5391                 let pending_update_fee = if let Some(feerate) = pending_update_fee_value {
5392                         Some((feerate, if channel_parameters.is_outbound_from_holder {
5393                                 FeeUpdateState::Outbound
5394                         } else {
5395                                 FeeUpdateState::AwaitingRemoteRevokeToAnnounce
5396                         }))
5397                 } else {
5398                         None
5399                 };
5400
5401                 let mut announcement_sigs = None;
5402                 let mut target_closing_feerate_sats_per_kw = None;
5403                 read_tlv_fields!(reader, {
5404                         (0, announcement_sigs, option),
5405                         (1, minimum_depth, option),
5406                         (3, counterparty_selected_channel_reserve_satoshis, option),
5407                         (5, config, option), // Note that if none is provided we will *not* overwrite the existing one.
5408                         (7, shutdown_scriptpubkey, option),
5409                         (9, target_closing_feerate_sats_per_kw, option),
5410                 });
5411
5412                 let mut secp_ctx = Secp256k1::new();
5413                 secp_ctx.seeded_randomize(&keys_source.get_secure_random_bytes());
5414
5415                 Ok(Channel {
5416                         user_id,
5417
5418                         config: config.unwrap(),
5419                         channel_id,
5420                         channel_state,
5421                         secp_ctx,
5422                         channel_value_satoshis,
5423
5424                         latest_monitor_update_id,
5425
5426                         holder_signer,
5427                         shutdown_scriptpubkey,
5428                         destination_script,
5429
5430                         cur_holder_commitment_transaction_number,
5431                         cur_counterparty_commitment_transaction_number,
5432                         value_to_self_msat,
5433
5434                         pending_inbound_htlcs,
5435                         pending_outbound_htlcs,
5436                         holding_cell_htlc_updates,
5437
5438                         resend_order,
5439
5440                         monitor_pending_funding_locked,
5441                         monitor_pending_revoke_and_ack,
5442                         monitor_pending_commitment_signed,
5443                         monitor_pending_forwards,
5444                         monitor_pending_failures,
5445
5446                         pending_update_fee,
5447                         holding_cell_update_fee,
5448                         next_holder_htlc_id,
5449                         next_counterparty_htlc_id,
5450                         update_time_counter,
5451                         feerate_per_kw,
5452
5453                         #[cfg(debug_assertions)]
5454                         holder_max_commitment_tx_output: Mutex::new((0, 0)),
5455                         #[cfg(debug_assertions)]
5456                         counterparty_max_commitment_tx_output: Mutex::new((0, 0)),
5457
5458                         last_sent_closing_fee: None,
5459                         pending_counterparty_closing_signed: None,
5460                         closing_fee_limits: None,
5461                         target_closing_feerate_sats_per_kw,
5462
5463                         funding_tx_confirmed_in,
5464                         funding_tx_confirmation_height,
5465                         short_channel_id,
5466
5467                         counterparty_dust_limit_satoshis,
5468                         holder_dust_limit_satoshis,
5469                         counterparty_max_htlc_value_in_flight_msat,
5470                         counterparty_selected_channel_reserve_satoshis,
5471                         counterparty_htlc_minimum_msat,
5472                         holder_htlc_minimum_msat,
5473                         counterparty_max_accepted_htlcs,
5474                         minimum_depth,
5475
5476                         counterparty_forwarding_info,
5477
5478                         channel_transaction_parameters: channel_parameters,
5479                         funding_transaction,
5480
5481                         counterparty_cur_commitment_point,
5482                         counterparty_prev_commitment_point,
5483                         counterparty_node_id,
5484
5485                         counterparty_shutdown_scriptpubkey,
5486
5487                         commitment_secrets,
5488
5489                         channel_update_status,
5490                         closing_signed_in_flight: false,
5491
5492                         announcement_sigs,
5493
5494                         #[cfg(any(test, feature = "fuzztarget"))]
5495                         next_local_commitment_tx_fee_info_cached: Mutex::new(None),
5496                         #[cfg(any(test, feature = "fuzztarget"))]
5497                         next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
5498
5499                         workaround_lnd_bug_4006: None,
5500
5501                         #[cfg(any(test, feature = "fuzztarget"))]
5502                         historical_inbound_htlc_fulfills,
5503                 })
5504         }
5505 }
5506
5507 #[cfg(test)]
5508 mod tests {
5509         use bitcoin::util::bip143;
5510         use bitcoin::consensus::encode::serialize;
5511         use bitcoin::blockdata::script::{Script, Builder};
5512         use bitcoin::blockdata::transaction::{Transaction, TxOut, SigHashType};
5513         use bitcoin::blockdata::constants::genesis_block;
5514         use bitcoin::blockdata::opcodes;
5515         use bitcoin::network::constants::Network;
5516         use bitcoin::hashes::hex::FromHex;
5517         use hex;
5518         use ln::{PaymentPreimage, PaymentHash};
5519         use ln::channelmanager::HTLCSource;
5520         use ln::channel::{Channel,InboundHTLCOutput,OutboundHTLCOutput,InboundHTLCState,OutboundHTLCState,HTLCOutputInCommitment,HTLCCandidate,HTLCInitiator,TxCreationKeys};
5521         use ln::channel::MAX_FUNDING_SATOSHIS;
5522         use ln::features::InitFeatures;
5523         use ln::msgs::{ChannelUpdate, DataLossProtect, DecodeError, OptionalField, UnsignedChannelUpdate};
5524         use ln::script::ShutdownScript;
5525         use ln::chan_utils;
5526         use ln::chan_utils::{ChannelPublicKeys, HolderCommitmentTransaction, CounterpartyChannelTransactionParameters, HTLC_SUCCESS_TX_WEIGHT, HTLC_TIMEOUT_TX_WEIGHT};
5527         use chain::BestBlock;
5528         use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
5529         use chain::keysinterface::{InMemorySigner, KeysInterface, BaseSign};
5530         use chain::transaction::OutPoint;
5531         use util::config::UserConfig;
5532         use util::enforcing_trait_impls::EnforcingSigner;
5533         use util::errors::APIError;
5534         use util::test_utils;
5535         use util::test_utils::OnGetShutdownScriptpubkey;
5536         use util::logger::Logger;
5537         use bitcoin::secp256k1::{Secp256k1, Message, Signature, All};
5538         use bitcoin::secp256k1::ffi::Signature as FFISignature;
5539         use bitcoin::secp256k1::key::{SecretKey,PublicKey};
5540         use bitcoin::secp256k1::recovery::RecoverableSignature;
5541         use bitcoin::hashes::sha256::Hash as Sha256;
5542         use bitcoin::hashes::Hash;
5543         use bitcoin::hash_types::{Txid, WPubkeyHash};
5544         use core::num::NonZeroU8;
5545         use sync::Arc;
5546         use prelude::*;
5547
5548         struct TestFeeEstimator {
5549                 fee_est: u32
5550         }
5551         impl FeeEstimator for TestFeeEstimator {
5552                 fn get_est_sat_per_1000_weight(&self, _: ConfirmationTarget) -> u32 {
5553                         self.fee_est
5554                 }
5555         }
5556
5557         #[test]
5558         fn test_max_funding_satoshis() {
5559                 assert!(MAX_FUNDING_SATOSHIS <= 21_000_000 * 100_000_000,
5560                         "MAX_FUNDING_SATOSHIS is greater than all satoshis in existence");
5561         }
5562
5563         struct Keys {
5564                 signer: InMemorySigner,
5565         }
5566         impl KeysInterface for Keys {
5567                 type Signer = InMemorySigner;
5568
5569                 fn get_node_secret(&self) -> SecretKey { panic!(); }
5570                 fn get_destination_script(&self) -> Script {
5571                         let secp_ctx = Secp256k1::signing_only();
5572                         let channel_monitor_claim_key = SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap();
5573                         let channel_monitor_claim_key_hash = WPubkeyHash::hash(&PublicKey::from_secret_key(&secp_ctx, &channel_monitor_claim_key).serialize());
5574                         Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&channel_monitor_claim_key_hash[..]).into_script()
5575                 }
5576
5577                 fn get_shutdown_scriptpubkey(&self) -> ShutdownScript {
5578                         let secp_ctx = Secp256k1::signing_only();
5579                         let channel_close_key = SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap();
5580                         ShutdownScript::new_p2wpkh_from_pubkey(PublicKey::from_secret_key(&secp_ctx, &channel_close_key))
5581                 }
5582
5583                 fn get_channel_signer(&self, _inbound: bool, _channel_value_satoshis: u64) -> InMemorySigner {
5584                         self.signer.clone()
5585                 }
5586                 fn get_secure_random_bytes(&self) -> [u8; 32] { [0; 32] }
5587                 fn read_chan_signer(&self, _data: &[u8]) -> Result<Self::Signer, DecodeError> { panic!(); }
5588                 fn sign_invoice(&self, _invoice_preimage: Vec<u8>) -> Result<RecoverableSignature, ()> { panic!(); }
5589         }
5590
5591         fn public_from_secret_hex(secp_ctx: &Secp256k1<All>, hex: &str) -> PublicKey {
5592                 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode(hex).unwrap()[..]).unwrap())
5593         }
5594
5595         #[test]
5596         fn upfront_shutdown_script_incompatibility() {
5597                 let features = InitFeatures::known().clear_shutdown_anysegwit();
5598                 let non_v0_segwit_shutdown_script =
5599                         ShutdownScript::new_witness_program(NonZeroU8::new(16).unwrap(), &[0, 40]).unwrap();
5600
5601                 let seed = [42; 32];
5602                 let network = Network::Testnet;
5603                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5604                 keys_provider.expect(OnGetShutdownScriptpubkey {
5605                         returns: non_v0_segwit_shutdown_script.clone(),
5606                 });
5607
5608                 let fee_estimator = TestFeeEstimator { fee_est: 253 };
5609                 let secp_ctx = Secp256k1::new();
5610                 let node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5611                 let config = UserConfig::default();
5612                 match Channel::<EnforcingSigner>::new_outbound(&&fee_estimator, &&keys_provider, node_id, &features, 10000000, 100000, 42, &config) {
5613                         Err(APIError::IncompatibleShutdownScript { script }) => {
5614                                 assert_eq!(script.into_inner(), non_v0_segwit_shutdown_script.into_inner());
5615                         },
5616                         Err(e) => panic!("Unexpected error: {:?}", e),
5617                         Ok(_) => panic!("Expected error"),
5618                 }
5619         }
5620
5621         // Check that, during channel creation, we use the same feerate in the open channel message
5622         // as we do in the Channel object creation itself.
5623         #[test]
5624         fn test_open_channel_msg_fee() {
5625                 let original_fee = 253;
5626                 let mut fee_est = TestFeeEstimator{fee_est: original_fee };
5627                 let secp_ctx = Secp256k1::new();
5628                 let seed = [42; 32];
5629                 let network = Network::Testnet;
5630                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5631
5632                 let node_a_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5633                 let config = UserConfig::default();
5634                 let node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&fee_est, &&keys_provider, node_a_node_id, &InitFeatures::known(), 10000000, 100000, 42, &config).unwrap();
5635
5636                 // Now change the fee so we can check that the fee in the open_channel message is the
5637                 // same as the old fee.
5638                 fee_est.fee_est = 500;
5639                 let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.block_hash());
5640                 assert_eq!(open_channel_msg.feerate_per_kw, original_fee);
5641         }
5642
5643         #[test]
5644         fn test_holder_vs_counterparty_dust_limit() {
5645                 // Test that when calculating the local and remote commitment transaction fees, the correct
5646                 // dust limits are used.
5647                 let feeest = TestFeeEstimator{fee_est: 15000};
5648                 let secp_ctx = Secp256k1::new();
5649                 let seed = [42; 32];
5650                 let network = Network::Testnet;
5651                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5652
5653                 // Go through the flow of opening a channel between two nodes, making sure
5654                 // they have different dust limits.
5655
5656                 // Create Node A's channel pointing to Node B's pubkey
5657                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5658                 let config = UserConfig::default();
5659                 let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, &InitFeatures::known(), 10000000, 100000, 42, &config).unwrap();
5660
5661                 // Create Node B's channel by receiving Node A's open_channel message
5662                 // Make sure A's dust limit is as we expect.
5663                 let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.block_hash());
5664                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
5665                 let node_b_chan = Channel::<EnforcingSigner>::new_from_req(&&feeest, &&keys_provider, node_b_node_id, &InitFeatures::known(), &open_channel_msg, 7, &config).unwrap();
5666
5667                 // Node B --> Node A: accept channel, explicitly setting B's dust limit.
5668                 let mut accept_channel_msg = node_b_chan.get_accept_channel();
5669                 accept_channel_msg.dust_limit_satoshis = 546;
5670                 node_a_chan.accept_channel(&accept_channel_msg, &config, &InitFeatures::known()).unwrap();
5671                 node_a_chan.holder_dust_limit_satoshis = 1560;
5672
5673                 // Put some inbound and outbound HTLCs in A's channel.
5674                 let htlc_amount_msat = 11_092_000; // put an amount below A's effective dust limit but above B's.
5675                 node_a_chan.pending_inbound_htlcs.push(InboundHTLCOutput {
5676                         htlc_id: 0,
5677                         amount_msat: htlc_amount_msat,
5678                         payment_hash: PaymentHash(Sha256::hash(&[42; 32]).into_inner()),
5679                         cltv_expiry: 300000000,
5680                         state: InboundHTLCState::Committed,
5681                 });
5682
5683                 node_a_chan.pending_outbound_htlcs.push(OutboundHTLCOutput {
5684                         htlc_id: 1,
5685                         amount_msat: htlc_amount_msat, // put an amount below A's dust amount but above B's.
5686                         payment_hash: PaymentHash(Sha256::hash(&[43; 32]).into_inner()),
5687                         cltv_expiry: 200000000,
5688                         state: OutboundHTLCState::Committed,
5689                         source: HTLCSource::OutboundRoute {
5690                                 path: Vec::new(),
5691                                 session_priv: SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(),
5692                                 first_hop_htlc_msat: 548,
5693                         }
5694                 });
5695
5696                 // Make sure when Node A calculates their local commitment transaction, none of the HTLCs pass
5697                 // the dust limit check.
5698                 let htlc_candidate = HTLCCandidate::new(htlc_amount_msat, HTLCInitiator::LocalOffered);
5699                 let local_commit_tx_fee = node_a_chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
5700                 let local_commit_fee_0_htlcs = node_a_chan.commit_tx_fee_msat(0);
5701                 assert_eq!(local_commit_tx_fee, local_commit_fee_0_htlcs);
5702
5703                 // Finally, make sure that when Node A calculates the remote's commitment transaction fees, all
5704                 // of the HTLCs are seen to be above the dust limit.
5705                 node_a_chan.channel_transaction_parameters.is_outbound_from_holder = false;
5706                 let remote_commit_fee_3_htlcs = node_a_chan.commit_tx_fee_msat(3);
5707                 let htlc_candidate = HTLCCandidate::new(htlc_amount_msat, HTLCInitiator::LocalOffered);
5708                 let remote_commit_tx_fee = node_a_chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
5709                 assert_eq!(remote_commit_tx_fee, remote_commit_fee_3_htlcs);
5710         }
5711
5712         #[test]
5713         fn test_timeout_vs_success_htlc_dust_limit() {
5714                 // Make sure that when `next_remote_commit_tx_fee_msat` and `next_local_commit_tx_fee_msat`
5715                 // calculate the real dust limits for HTLCs (i.e. the dust limit given by the counterparty
5716                 // *plus* the fees paid for the HTLC) they don't swap `HTLC_SUCCESS_TX_WEIGHT` for
5717                 // `HTLC_TIMEOUT_TX_WEIGHT`, and vice versa.
5718                 let fee_est = TestFeeEstimator{fee_est: 253 };
5719                 let secp_ctx = Secp256k1::new();
5720                 let seed = [42; 32];
5721                 let network = Network::Testnet;
5722                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5723
5724                 let node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5725                 let config = UserConfig::default();
5726                 let mut chan = Channel::<EnforcingSigner>::new_outbound(&&fee_est, &&keys_provider, node_id, &InitFeatures::known(), 10000000, 100000, 42, &config).unwrap();
5727
5728                 let commitment_tx_fee_0_htlcs = chan.commit_tx_fee_msat(0);
5729                 let commitment_tx_fee_1_htlc = chan.commit_tx_fee_msat(1);
5730
5731                 // If HTLC_SUCCESS_TX_WEIGHT and HTLC_TIMEOUT_TX_WEIGHT were swapped: then this HTLC would be
5732                 // counted as dust when it shouldn't be.
5733                 let htlc_amt_above_timeout = ((253 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + chan.holder_dust_limit_satoshis + 1) * 1000;
5734                 let htlc_candidate = HTLCCandidate::new(htlc_amt_above_timeout, HTLCInitiator::LocalOffered);
5735                 let commitment_tx_fee = chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
5736                 assert_eq!(commitment_tx_fee, commitment_tx_fee_1_htlc);
5737
5738                 // If swapped: this HTLC would be counted as non-dust when it shouldn't be.
5739                 let dust_htlc_amt_below_success = ((253 * HTLC_SUCCESS_TX_WEIGHT / 1000) + chan.holder_dust_limit_satoshis - 1) * 1000;
5740                 let htlc_candidate = HTLCCandidate::new(dust_htlc_amt_below_success, HTLCInitiator::RemoteOffered);
5741                 let commitment_tx_fee = chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
5742                 assert_eq!(commitment_tx_fee, commitment_tx_fee_0_htlcs);
5743
5744                 chan.channel_transaction_parameters.is_outbound_from_holder = false;
5745
5746                 // If swapped: this HTLC would be counted as non-dust when it shouldn't be.
5747                 let dust_htlc_amt_above_timeout = ((253 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + chan.counterparty_dust_limit_satoshis + 1) * 1000;
5748                 let htlc_candidate = HTLCCandidate::new(dust_htlc_amt_above_timeout, HTLCInitiator::LocalOffered);
5749                 let commitment_tx_fee = chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
5750                 assert_eq!(commitment_tx_fee, commitment_tx_fee_0_htlcs);
5751
5752                 // If swapped: this HTLC would be counted as dust when it shouldn't be.
5753                 let htlc_amt_below_success = ((253 * HTLC_SUCCESS_TX_WEIGHT / 1000) + chan.counterparty_dust_limit_satoshis - 1) * 1000;
5754                 let htlc_candidate = HTLCCandidate::new(htlc_amt_below_success, HTLCInitiator::RemoteOffered);
5755                 let commitment_tx_fee = chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
5756                 assert_eq!(commitment_tx_fee, commitment_tx_fee_1_htlc);
5757         }
5758
5759         #[test]
5760         fn channel_reestablish_no_updates() {
5761                 let feeest = TestFeeEstimator{fee_est: 15000};
5762                 let logger = test_utils::TestLogger::new();
5763                 let secp_ctx = Secp256k1::new();
5764                 let seed = [42; 32];
5765                 let network = Network::Testnet;
5766                 let best_block = BestBlock::from_genesis(network);
5767                 let chain_hash = best_block.block_hash();
5768                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5769
5770                 // Go through the flow of opening a channel between two nodes.
5771
5772                 // Create Node A's channel pointing to Node B's pubkey
5773                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5774                 let config = UserConfig::default();
5775                 let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, &InitFeatures::known(), 10000000, 100000, 42, &config).unwrap();
5776
5777                 // Create Node B's channel by receiving Node A's open_channel message
5778                 let open_channel_msg = node_a_chan.get_open_channel(chain_hash);
5779                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
5780                 let mut node_b_chan = Channel::<EnforcingSigner>::new_from_req(&&feeest, &&keys_provider, node_b_node_id, &InitFeatures::known(), &open_channel_msg, 7, &config).unwrap();
5781
5782                 // Node B --> Node A: accept channel
5783                 let accept_channel_msg = node_b_chan.get_accept_channel();
5784                 node_a_chan.accept_channel(&accept_channel_msg, &config, &InitFeatures::known()).unwrap();
5785
5786                 // Node A --> Node B: funding created
5787                 let output_script = node_a_chan.get_funding_redeemscript();
5788                 let tx = Transaction { version: 1, lock_time: 0, input: Vec::new(), output: vec![TxOut {
5789                         value: 10000000, script_pubkey: output_script.clone(),
5790                 }]};
5791                 let funding_outpoint = OutPoint{ txid: tx.txid(), index: 0 };
5792                 let funding_created_msg = node_a_chan.get_outbound_funding_created(tx.clone(), funding_outpoint, &&logger).unwrap();
5793                 let (funding_signed_msg, _) = node_b_chan.funding_created(&funding_created_msg, best_block, &&logger).unwrap();
5794
5795                 // Node B --> Node A: funding signed
5796                 let _ = node_a_chan.funding_signed(&funding_signed_msg, best_block, &&logger);
5797
5798                 // Now disconnect the two nodes and check that the commitment point in
5799                 // Node B's channel_reestablish message is sane.
5800                 node_b_chan.remove_uncommitted_htlcs_and_mark_paused(&&logger);
5801                 let msg = node_b_chan.get_channel_reestablish(&&logger);
5802                 assert_eq!(msg.next_local_commitment_number, 1); // now called next_commitment_number
5803                 assert_eq!(msg.next_remote_commitment_number, 0); // now called next_revocation_number
5804                 match msg.data_loss_protect {
5805                         OptionalField::Present(DataLossProtect { your_last_per_commitment_secret, .. }) => {
5806                                 assert_eq!(your_last_per_commitment_secret, [0; 32]);
5807                         },
5808                         _ => panic!()
5809                 }
5810
5811                 // Check that the commitment point in Node A's channel_reestablish message
5812                 // is sane.
5813                 node_a_chan.remove_uncommitted_htlcs_and_mark_paused(&&logger);
5814                 let msg = node_a_chan.get_channel_reestablish(&&logger);
5815                 assert_eq!(msg.next_local_commitment_number, 1); // now called next_commitment_number
5816                 assert_eq!(msg.next_remote_commitment_number, 0); // now called next_revocation_number
5817                 match msg.data_loss_protect {
5818                         OptionalField::Present(DataLossProtect { your_last_per_commitment_secret, .. }) => {
5819                                 assert_eq!(your_last_per_commitment_secret, [0; 32]);
5820                         },
5821                         _ => panic!()
5822                 }
5823         }
5824
5825         #[test]
5826         fn channel_update() {
5827                 let feeest = TestFeeEstimator{fee_est: 15000};
5828                 let secp_ctx = Secp256k1::new();
5829                 let seed = [42; 32];
5830                 let network = Network::Testnet;
5831                 let chain_hash = genesis_block(network).header.block_hash();
5832                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5833
5834                 // Create a channel.
5835                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5836                 let config = UserConfig::default();
5837                 let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, &InitFeatures::known(), 10000000, 100000, 42, &config).unwrap();
5838                 assert!(node_a_chan.counterparty_forwarding_info.is_none());
5839                 assert_eq!(node_a_chan.holder_htlc_minimum_msat, 1); // the default
5840                 assert!(node_a_chan.counterparty_forwarding_info().is_none());
5841
5842                 // Make sure that receiving a channel update will update the Channel as expected.
5843                 let update = ChannelUpdate {
5844                         contents: UnsignedChannelUpdate {
5845                                 chain_hash,
5846                                 short_channel_id: 0,
5847                                 timestamp: 0,
5848                                 flags: 0,
5849                                 cltv_expiry_delta: 100,
5850                                 htlc_minimum_msat: 5,
5851                                 htlc_maximum_msat: OptionalField::Absent,
5852                                 fee_base_msat: 110,
5853                                 fee_proportional_millionths: 11,
5854                                 excess_data: Vec::new(),
5855                         },
5856                         signature: Signature::from(unsafe { FFISignature::new() })
5857                 };
5858                 node_a_chan.channel_update(&update).unwrap();
5859
5860                 // The counterparty can send an update with a higher minimum HTLC, but that shouldn't
5861                 // change our official htlc_minimum_msat.
5862                 assert_eq!(node_a_chan.holder_htlc_minimum_msat, 1);
5863                 match node_a_chan.counterparty_forwarding_info() {
5864                         Some(info) => {
5865                                 assert_eq!(info.cltv_expiry_delta, 100);
5866                                 assert_eq!(info.fee_base_msat, 110);
5867                                 assert_eq!(info.fee_proportional_millionths, 11);
5868                         },
5869                         None => panic!("expected counterparty forwarding info to be Some")
5870                 }
5871         }
5872
5873         #[test]
5874         fn outbound_commitment_test() {
5875                 // Test vectors from BOLT 3 Appendix C:
5876                 let feeest = TestFeeEstimator{fee_est: 15000};
5877                 let logger : Arc<Logger> = Arc::new(test_utils::TestLogger::new());
5878                 let secp_ctx = Secp256k1::new();
5879
5880                 let mut signer = InMemorySigner::new(
5881                         &secp_ctx,
5882                         SecretKey::from_slice(&hex::decode("30ff4956bbdd3222d44cc5e8a1261dab1e07957bdac5ae88fe3261ef321f3749").unwrap()[..]).unwrap(),
5883                         SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(),
5884                         SecretKey::from_slice(&hex::decode("1111111111111111111111111111111111111111111111111111111111111111").unwrap()[..]).unwrap(),
5885                         SecretKey::from_slice(&hex::decode("3333333333333333333333333333333333333333333333333333333333333333").unwrap()[..]).unwrap(),
5886                         SecretKey::from_slice(&hex::decode("1111111111111111111111111111111111111111111111111111111111111111").unwrap()[..]).unwrap(),
5887
5888                         // These aren't set in the test vectors:
5889                         [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],
5890                         10_000_000,
5891                         [0; 32]
5892                 );
5893
5894                 assert_eq!(signer.pubkeys().funding_pubkey.serialize()[..],
5895                                 hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]);
5896                 let keys_provider = Keys { signer: signer.clone() };
5897
5898                 let counterparty_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5899                 let mut config = UserConfig::default();
5900                 config.channel_options.announced_channel = false;
5901                 let mut chan = Channel::<InMemorySigner>::new_outbound(&&feeest, &&keys_provider, counterparty_node_id, &InitFeatures::known(), 10_000_000, 100000, 42, &config).unwrap(); // Nothing uses their network key in this test
5902                 chan.holder_dust_limit_satoshis = 546;
5903                 chan.counterparty_selected_channel_reserve_satoshis = Some(0); // Filled in in accept_channel
5904
5905                 let funding_info = OutPoint{ txid: Txid::from_hex("8984484a580b825b9972d7adb15050b3ab624ccd731946b3eeddb92f4e7ef6be").unwrap(), index: 0 };
5906
5907                 let counterparty_pubkeys = ChannelPublicKeys {
5908                         funding_pubkey: public_from_secret_hex(&secp_ctx, "1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13"),
5909                         revocation_basepoint: PublicKey::from_slice(&hex::decode("02466d7fcae563e5cb09a0d1870bb580344804617879a14949cf22285f1bae3f27").unwrap()[..]).unwrap(),
5910                         payment_point: public_from_secret_hex(&secp_ctx, "4444444444444444444444444444444444444444444444444444444444444444"),
5911                         delayed_payment_basepoint: public_from_secret_hex(&secp_ctx, "1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13"),
5912                         htlc_basepoint: public_from_secret_hex(&secp_ctx, "4444444444444444444444444444444444444444444444444444444444444444")
5913                 };
5914                 chan.channel_transaction_parameters.counterparty_parameters = Some(
5915                         CounterpartyChannelTransactionParameters {
5916                                 pubkeys: counterparty_pubkeys.clone(),
5917                                 selected_contest_delay: 144
5918                         });
5919                 chan.channel_transaction_parameters.funding_outpoint = Some(funding_info);
5920                 signer.ready_channel(&chan.channel_transaction_parameters);
5921
5922                 assert_eq!(counterparty_pubkeys.payment_point.serialize()[..],
5923                            hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
5924
5925                 assert_eq!(counterparty_pubkeys.funding_pubkey.serialize()[..],
5926                            hex::decode("030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c1").unwrap()[..]);
5927
5928                 assert_eq!(counterparty_pubkeys.htlc_basepoint.serialize()[..],
5929                            hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
5930
5931                 // We can't just use build_holder_transaction_keys here as the per_commitment_secret is not
5932                 // derived from a commitment_seed, so instead we copy it here and call
5933                 // build_commitment_transaction.
5934                 let delayed_payment_base = &chan.holder_signer.pubkeys().delayed_payment_basepoint;
5935                 let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
5936                 let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
5937                 let htlc_basepoint = &chan.holder_signer.pubkeys().htlc_basepoint;
5938                 let keys = TxCreationKeys::derive_new(&secp_ctx, &per_commitment_point, delayed_payment_base, htlc_basepoint, &counterparty_pubkeys.revocation_basepoint, &counterparty_pubkeys.htlc_basepoint).unwrap();
5939
5940                 macro_rules! test_commitment {
5941                         ( $counterparty_sig_hex: expr, $sig_hex: expr, $tx_hex: expr, {
5942                                 $( { $htlc_idx: expr, $counterparty_htlc_sig_hex: expr, $htlc_sig_hex: expr, $htlc_tx_hex: expr } ), *
5943                         } ) => { {
5944                                 let (commitment_tx, htlcs): (_, Vec<HTLCOutputInCommitment>) = {
5945                                         let mut res = chan.build_commitment_transaction(0xffffffffffff - 42, &keys, true, false, &logger);
5946
5947                                         let htlcs = res.3.drain(..)
5948                                                 .filter_map(|(htlc, _)| if htlc.transaction_output_index.is_some() { Some(htlc) } else { None })
5949                                                 .collect();
5950                                         (res.0, htlcs)
5951                                 };
5952                                 let trusted_tx = commitment_tx.trust();
5953                                 let unsigned_tx = trusted_tx.built_transaction();
5954                                 let redeemscript = chan.get_funding_redeemscript();
5955                                 let counterparty_signature = Signature::from_der(&hex::decode($counterparty_sig_hex).unwrap()[..]).unwrap();
5956                                 let sighash = unsigned_tx.get_sighash_all(&redeemscript, chan.channel_value_satoshis);
5957                                 secp_ctx.verify(&sighash, &counterparty_signature, chan.counterparty_funding_pubkey()).unwrap();
5958
5959                                 let mut per_htlc: Vec<(HTLCOutputInCommitment, Option<Signature>)> = Vec::new();
5960                                 per_htlc.clear(); // Don't warn about excess mut for no-HTLC calls
5961                                 let mut counterparty_htlc_sigs = Vec::new();
5962                                 counterparty_htlc_sigs.clear(); // Don't warn about excess mut for no-HTLC calls
5963                                 $({
5964                                         let remote_signature = Signature::from_der(&hex::decode($counterparty_htlc_sig_hex).unwrap()[..]).unwrap();
5965                                         per_htlc.push((htlcs[$htlc_idx].clone(), Some(remote_signature)));
5966                                         counterparty_htlc_sigs.push(remote_signature);
5967                                 })*
5968                                 assert_eq!(htlcs.len(), per_htlc.len());
5969
5970                                 let holder_commitment_tx = HolderCommitmentTransaction::new(
5971                                         commitment_tx.clone(),
5972                                         counterparty_signature,
5973                                         counterparty_htlc_sigs,
5974                                         &chan.holder_signer.pubkeys().funding_pubkey,
5975                                         chan.counterparty_funding_pubkey()
5976                                 );
5977                                 let (holder_sig, htlc_sigs) = signer.sign_holder_commitment_and_htlcs(&holder_commitment_tx, &secp_ctx).unwrap();
5978                                 assert_eq!(Signature::from_der(&hex::decode($sig_hex).unwrap()[..]).unwrap(), holder_sig, "holder_sig");
5979
5980                                 let funding_redeemscript = chan.get_funding_redeemscript();
5981                                 let tx = holder_commitment_tx.add_holder_sig(&funding_redeemscript, holder_sig);
5982                                 assert_eq!(serialize(&tx)[..], hex::decode($tx_hex).unwrap()[..], "tx");
5983
5984                                 // ((htlc, counterparty_sig), (index, holder_sig))
5985                                 let mut htlc_sig_iter = holder_commitment_tx.htlcs().iter().zip(&holder_commitment_tx.counterparty_htlc_sigs).zip(htlc_sigs.iter().enumerate());
5986
5987                                 $({
5988                                         let remote_signature = Signature::from_der(&hex::decode($counterparty_htlc_sig_hex).unwrap()[..]).unwrap();
5989
5990                                         let ref htlc = htlcs[$htlc_idx];
5991                                         let htlc_tx = chan_utils::build_htlc_transaction(&unsigned_tx.txid, chan.feerate_per_kw,
5992                                                 chan.get_counterparty_selected_contest_delay().unwrap(),
5993                                                 &htlc, &keys.broadcaster_delayed_payment_key, &keys.revocation_key);
5994                                         let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys);
5995                                         let htlc_sighash = Message::from_slice(&bip143::SigHashCache::new(&htlc_tx).signature_hash(0, &htlc_redeemscript, htlc.amount_msat / 1000, SigHashType::All)[..]).unwrap();
5996                                         secp_ctx.verify(&htlc_sighash, &remote_signature, &keys.countersignatory_htlc_key).unwrap();
5997
5998                                         let mut preimage: Option<PaymentPreimage> = None;
5999                                         if !htlc.offered {
6000                                                 for i in 0..5 {
6001                                                         let out = PaymentHash(Sha256::hash(&[i; 32]).into_inner());
6002                                                         if out == htlc.payment_hash {
6003                                                                 preimage = Some(PaymentPreimage([i; 32]));
6004                                                         }
6005                                                 }
6006
6007                                                 assert!(preimage.is_some());
6008                                         }
6009
6010                                         let htlc_sig = htlc_sig_iter.next().unwrap();
6011                                         assert_eq!((htlc_sig.0).0.transaction_output_index, Some($htlc_idx), "output index");
6012
6013                                         let signature = Signature::from_der(&hex::decode($htlc_sig_hex).unwrap()[..]).unwrap();
6014                                         assert_eq!(signature, *(htlc_sig.1).1, "htlc sig");
6015                                         let index = (htlc_sig.1).0;
6016                                         let channel_parameters = chan.channel_transaction_parameters.as_holder_broadcastable();
6017                                         let trusted_tx = holder_commitment_tx.trust();
6018                                         assert_eq!(serialize(&trusted_tx.get_signed_htlc_tx(&channel_parameters, index, &(htlc_sig.0).1, (htlc_sig.1).1, &preimage))[..],
6019                                                         hex::decode($htlc_tx_hex).unwrap()[..], "htlc tx");
6020                                 })*
6021                                 assert!(htlc_sig_iter.next().is_none());
6022                         } }
6023                 }
6024
6025                 // simple commitment tx with no HTLCs
6026                 chan.value_to_self_msat = 7000000000;
6027
6028                 test_commitment!("3045022100c3127b33dcc741dd6b05b1e63cbd1a9a7d816f37af9b6756fa2376b056f032370220408b96279808fe57eb7e463710804cdf4f108388bc5cf722d8c848d2c7f9f3b0",
6029                                                  "30440220616210b2cc4d3afb601013c373bbd8aac54febd9f15400379a8cb65ce7deca60022034236c010991beb7ff770510561ae8dc885b8d38d1947248c38f2ae055647142",
6030                                                  "02000000000101bef67e4e2fb9ddeeb3461973cd4c62abb35050b1add772995b820b584a488489000000000038b02b8002c0c62d0000000000160014cc1b07838e387deacd0e5232e1e8b49f4c29e48454a56a00000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e04004730440220616210b2cc4d3afb601013c373bbd8aac54febd9f15400379a8cb65ce7deca60022034236c010991beb7ff770510561ae8dc885b8d38d1947248c38f2ae05564714201483045022100c3127b33dcc741dd6b05b1e63cbd1a9a7d816f37af9b6756fa2376b056f032370220408b96279808fe57eb7e463710804cdf4f108388bc5cf722d8c848d2c7f9f3b001475221023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb21030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c152ae3e195220", {});
6031
6032                 chan.pending_inbound_htlcs.push({
6033                         let mut out = InboundHTLCOutput{
6034                                 htlc_id: 0,
6035                                 amount_msat: 1000000,
6036                                 cltv_expiry: 500,
6037                                 payment_hash: PaymentHash([0; 32]),
6038                                 state: InboundHTLCState::Committed,
6039                         };
6040                         out.payment_hash.0 = Sha256::hash(&hex::decode("0000000000000000000000000000000000000000000000000000000000000000").unwrap()).into_inner();
6041                         out
6042                 });
6043                 chan.pending_inbound_htlcs.push({
6044                         let mut out = InboundHTLCOutput{
6045                                 htlc_id: 1,
6046                                 amount_msat: 2000000,
6047                                 cltv_expiry: 501,
6048                                 payment_hash: PaymentHash([0; 32]),
6049                                 state: InboundHTLCState::Committed,
6050                         };
6051                         out.payment_hash.0 = Sha256::hash(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()).into_inner();
6052                         out
6053                 });
6054                 chan.pending_outbound_htlcs.push({
6055                         let mut out = OutboundHTLCOutput{
6056                                 htlc_id: 2,
6057                                 amount_msat: 2000000,
6058                                 cltv_expiry: 502,
6059                                 payment_hash: PaymentHash([0; 32]),
6060                                 state: OutboundHTLCState::Committed,
6061                                 source: HTLCSource::dummy(),
6062                         };
6063                         out.payment_hash.0 = Sha256::hash(&hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap()).into_inner();
6064                         out
6065                 });
6066                 chan.pending_outbound_htlcs.push({
6067                         let mut out = OutboundHTLCOutput{
6068                                 htlc_id: 3,
6069                                 amount_msat: 3000000,
6070                                 cltv_expiry: 503,
6071                                 payment_hash: PaymentHash([0; 32]),
6072                                 state: OutboundHTLCState::Committed,
6073                                 source: HTLCSource::dummy(),
6074                         };
6075                         out.payment_hash.0 = Sha256::hash(&hex::decode("0303030303030303030303030303030303030303030303030303030303030303").unwrap()).into_inner();
6076                         out
6077                 });
6078                 chan.pending_inbound_htlcs.push({
6079                         let mut out = InboundHTLCOutput{
6080                                 htlc_id: 4,
6081                                 amount_msat: 4000000,
6082                                 cltv_expiry: 504,
6083                                 payment_hash: PaymentHash([0; 32]),
6084                                 state: InboundHTLCState::Committed,
6085                         };
6086                         out.payment_hash.0 = Sha256::hash(&hex::decode("0404040404040404040404040404040404040404040404040404040404040404").unwrap()).into_inner();
6087                         out
6088                 });
6089
6090                 // commitment tx with all five HTLCs untrimmed (minimum feerate)
6091                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6092                 chan.feerate_per_kw = 0;
6093
6094                 test_commitment!("3044022009b048187705a8cbc9ad73adbe5af148c3d012e1f067961486c822c7af08158c022006d66f3704cfab3eb2dc49dae24e4aa22a6910fc9b424007583204e3621af2e5",
6095                                  "304402206fc2d1f10ea59951eefac0b4b7c396a3c3d87b71ff0b019796ef4535beaf36f902201765b0181e514d04f4c8ad75659d7037be26cdb3f8bb6f78fe61decef484c3ea",
6096                                  "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", {
6097
6098                                   { 0,
6099                                   "3045022100d9e29616b8f3959f1d3d7f7ce893ffedcdc407717d0de8e37d808c91d3a7c50d022078c3033f6d00095c8720a4bc943c1b45727818c082e4e3ddbc6d3116435b624b",
6100                                   "30440220636de5682ef0c5b61f124ec74e8aa2461a69777521d6998295dcea36bc3338110220165285594b23c50b28b82df200234566628a27bcd17f7f14404bd865354eb3ce",
6101                                   "02000000000101ab84ff284f162cfbfef241f853b47d4368d171f9e2a1445160cd591c4c7d882b00000000000000000001e8030000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e0500483045022100d9e29616b8f3959f1d3d7f7ce893ffedcdc407717d0de8e37d808c91d3a7c50d022078c3033f6d00095c8720a4bc943c1b45727818c082e4e3ddbc6d3116435b624b014730440220636de5682ef0c5b61f124ec74e8aa2461a69777521d6998295dcea36bc3338110220165285594b23c50b28b82df200234566628a27bcd17f7f14404bd865354eb3ce012000000000000000000000000000000000000000000000000000000000000000008a76a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c8201208763a914b8bcb07f6344b42ab04250c86a6e8b75d3fdbbc688527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae677502f401b175ac686800000000" },
6102
6103                                   { 1,
6104                                   "30440220649fe8b20e67e46cbb0d09b4acea87dbec001b39b08dee7bdd0b1f03922a8640022037c462dff79df501cecfdb12ea7f4de91f99230bb544726f6e04527b1f896004",
6105                                   "3045022100803159dee7935dba4a1d36a61055ce8fd62caa528573cc221ae288515405a252022029c59e7cffce374fe860100a4a63787e105c3cf5156d40b12dd53ff55ac8cf3f",
6106                                   "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" },
6107
6108                                   { 2,
6109                                   "30440220770fc321e97a19f38985f2e7732dd9fe08d16a2efa4bcbc0429400a447faf49102204d40b417f3113e1b0944ae0986f517564ab4acd3d190503faf97a6e420d43352",
6110                                   "3045022100a437cc2ce77400ecde441b3398fea3c3ad8bdad8132be818227fe3c5b8345989022069d45e7fa0ae551ec37240845e2c561ceb2567eacf3076a6a43a502d05865faa",
6111                                   "02000000000101ab84ff284f162cfbfef241f853b47d4368d171f9e2a1445160cd591c4c7d882b02000000000000000001d0070000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e05004730440220770fc321e97a19f38985f2e7732dd9fe08d16a2efa4bcbc0429400a447faf49102204d40b417f3113e1b0944ae0986f517564ab4acd3d190503faf97a6e420d4335201483045022100a437cc2ce77400ecde441b3398fea3c3ad8bdad8132be818227fe3c5b8345989022069d45e7fa0ae551ec37240845e2c561ceb2567eacf3076a6a43a502d05865faa012001010101010101010101010101010101010101010101010101010101010101018a76a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c8201208763a9144b6b2e5444c2639cc0fb7bcea5afba3f3cdce23988527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae677502f501b175ac686800000000" },
6112
6113                                   { 3,
6114                                   "304402207bcbf4f60a9829b05d2dbab84ed593e0291836be715dc7db6b72a64caf646af802201e489a5a84f7c5cc130398b841d138d031a5137ac8f4c49c770a4959dc3c1363",
6115                                   "304402203121d9b9c055f354304b016a36662ee99e1110d9501cb271b087ddb6f382c2c80220549882f3f3b78d9c492de47543cb9a697cecc493174726146536c5954dac7487",
6116                                   "02000000000101ab84ff284f162cfbfef241f853b47d4368d171f9e2a1445160cd591c4c7d882b03000000000000000001b80b0000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e050047304402207bcbf4f60a9829b05d2dbab84ed593e0291836be715dc7db6b72a64caf646af802201e489a5a84f7c5cc130398b841d138d031a5137ac8f4c49c770a4959dc3c13630147304402203121d9b9c055f354304b016a36662ee99e1110d9501cb271b087ddb6f382c2c80220549882f3f3b78d9c492de47543cb9a697cecc493174726146536c5954dac748701008576a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c820120876475527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae67a9148a486ff2e31d6158bf39e2608864d63fefd09d5b88ac6868f7010000" },
6117
6118                                   { 4,
6119                                   "3044022076dca5cb81ba7e466e349b7128cdba216d4d01659e29b96025b9524aaf0d1899022060de85697b88b21c749702b7d2cfa7dfeaa1f472c8f1d7d9c23f2bf968464b87",
6120                                   "3045022100d9080f103cc92bac15ec42464a95f070c7fb6925014e673ee2ea1374d36a7f7502200c65294d22eb20d48564954d5afe04a385551919d8b2ddb4ae2459daaeee1d95",
6121                                   "02000000000101ab84ff284f162cfbfef241f853b47d4368d171f9e2a1445160cd591c4c7d882b04000000000000000001a00f0000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e0500473044022076dca5cb81ba7e466e349b7128cdba216d4d01659e29b96025b9524aaf0d1899022060de85697b88b21c749702b7d2cfa7dfeaa1f472c8f1d7d9c23f2bf968464b8701483045022100d9080f103cc92bac15ec42464a95f070c7fb6925014e673ee2ea1374d36a7f7502200c65294d22eb20d48564954d5afe04a385551919d8b2ddb4ae2459daaeee1d95012004040404040404040404040404040404040404040404040404040404040404048a76a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c8201208763a91418bc1a114ccf9c052d3d23e28d3b0a9d1227434288527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae677502f801b175ac686800000000" }
6122                 } );
6123
6124                 // commitment tx with seven outputs untrimmed (maximum feerate)
6125                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6126                 chan.feerate_per_kw = 647;
6127
6128                 test_commitment!("3045022100a135f9e8a5ed25f7277446c67956b00ce6f610ead2bdec2c2f686155b7814772022059f1f6e1a8b336a68efcc1af3fe4d422d4827332b5b067501b099c47b7b5b5ee",
6129                                  "30450221009ec15c687898bb4da8b3a833e5ab8bfc51ec6e9202aaa8e66611edfd4a85ed1102203d7183e45078b9735c93450bc3415d3e5a8c576141a711ec6ddcb4a893926bb7",
6130                                  "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", {
6131
6132                                   { 0,
6133                                   "30450221008437627f9ad84ac67052e2a414a4367b8556fd1f94d8b02590f89f50525cd33502205b9c21ff6e7fc864f2352746ad8ba59182510819acb644e25b8a12fc37bbf24f",
6134                                   "30440220344b0deb055230d01703e6c7acd45853c4af2328b49b5d8af4f88a060733406602202ea64f2a43d5751edfe75503cbc35a62e3141b5ed032fa03360faf4ca66f670b",
6135                                   "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" },
6136
6137                                   { 1,
6138                                   "304402205a67f92bf6845cf2892b48d874ac1daf88a36495cf8a06f93d83180d930a6f75022031da1621d95c3f335cc06a3056cf960199dae600b7cf89088f65fc53cdbef28c",
6139                                   "30450221009e5e3822b0185c6799a95288c597b671d6cc69ab80f43740f00c6c3d0752bdda02206da947a74bd98f3175324dc56fdba86cc783703a120a6f0297537e60632f4c7f",
6140                                   "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" },
6141
6142                                   { 2,
6143                                   "30440220437e21766054a3eef7f65690c5bcfa9920babbc5af92b819f772f6ea96df6c7402207173622024bd97328cfb26c6665e25c2f5d67c319443ccdc60c903217005d8c8",
6144                                   "3045022100fcfc47e36b712624677626cef3dc1d67f6583bd46926a6398fe6b00b0c9a37760220525788257b187fc775c6370d04eadf34d06f3650a63f8df851cee0ecb47a1673",
6145                                   "020000000001012cfb3e4788c206881d38f2996b6cb2109b5935acb527d14bdaa7b908afa9b2fe020000000000000000010a060000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e05004730440220437e21766054a3eef7f65690c5bcfa9920babbc5af92b819f772f6ea96df6c7402207173622024bd97328cfb26c6665e25c2f5d67c319443ccdc60c903217005d8c801483045022100fcfc47e36b712624677626cef3dc1d67f6583bd46926a6398fe6b00b0c9a37760220525788257b187fc775c6370d04eadf34d06f3650a63f8df851cee0ecb47a1673012001010101010101010101010101010101010101010101010101010101010101018a76a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c8201208763a9144b6b2e5444c2639cc0fb7bcea5afba3f3cdce23988527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae677502f501b175ac686800000000" },
6146
6147                                   { 3,
6148                                   "304402207436e10737e4df499fc051686d3e11a5bb2310e4d1f1e691d287cef66514791202207cb58e71a6b7a42dd001b7e3ae672ea4f71ea3e1cd412b742e9124abb0739c64",
6149                                   "3045022100e78211b8409afb7255ffe37337da87f38646f1faebbdd61bc1920d69e3ead67a02201a626305adfcd16bfb7e9340928d9b6305464eab4aa4c4a3af6646e9b9f69dee",
6150                                   "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" },
6151
6152                                   { 4,
6153                                   "30450221009acd6a827a76bfee50806178dfe0495cd4e1d9c58279c194c7b01520fe68cb8d022024d439047c368883e570997a7d40f0b430cb5a742f507965e7d3063ae3feccca",
6154                                   "3044022048762cf546bbfe474f1536365ea7c416e3c0389d60558bc9412cb148fb6ab68202207215d7083b75c96ff9d2b08c59c34e287b66820f530b486a9aa4cdd9c347d5b9",
6155                                   "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" }
6156                 } );
6157
6158                 // commitment tx with six outputs untrimmed (minimum feerate)
6159                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6160                 chan.feerate_per_kw = 648;
6161
6162                 test_commitment!("304402203948f900a5506b8de36a4d8502f94f21dd84fd9c2314ab427d52feaa7a0a19f2022059b6a37a4adaa2c5419dc8aea63c6e2a2ec4c4bde46207f6dc1fcd22152fc6e5",
6163                                  "3045022100b15f72908ba3382a34ca5b32519240a22300cc6015b6f9418635fb41f3d01d8802207adb331b9ed1575383dca0f2355e86c173802feecf8298fbea53b9d4610583e9",
6164                                  "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", {
6165
6166                                   { 0,
6167                                   "3045022100a031202f3be94678f0e998622ee95ebb6ada8da1e9a5110228b5e04a747351e4022010ca6a21e18314ed53cfaae3b1f51998552a61a468e596368829a50ce40110e0",
6168                                   "304502210097e1873b57267730154595187a34949d3744f52933070c74757005e61ce2112e02204ecfba2aa42d4f14bdf8bad4206bb97217b702e6c433e0e1b0ce6587e6d46ec6",
6169                                   "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" },
6170
6171                                   { 1,
6172                                   "304402202361012a634aee7835c5ecdd6413dcffa8f404b7e77364c792cff984e4ee71e90220715c5e90baa08daa45a7439b1ee4fa4843ed77b19c058240b69406606d384124",
6173                                   "3044022019de73b00f1d818fb388e83b2c8c31f6bce35ac624e215bc12f88f9dc33edf48022006ff814bb9f700ee6abc3294e146fac3efd4f13f0005236b41c0a946ee00c9ae",
6174                                   "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" },
6175
6176                                   { 2,
6177                                   "304402207e8e82cd71ed4febeb593732c260456836e97d81896153ecd2b3cf320ca6861702202dd4a30f68f98ced7cc56a36369ac1fdd978248c5ff4ed204fc00cc625532989",
6178                                   "3045022100bd0be6100c4fd8f102ec220e1b053e4c4e2ecca25615490150007b40d314dc3902201a1e0ea266965b43164d9e6576f58fa6726d42883dd1c3996d2925c2e2260796",
6179                                   "020000000001010f44041fdfba175987cf4e6135ba2a154e3b7fb96483dc0ed5efc0678e5b6bf1020000000000000000010b0a0000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e050047304402207e8e82cd71ed4febeb593732c260456836e97d81896153ecd2b3cf320ca6861702202dd4a30f68f98ced7cc56a36369ac1fdd978248c5ff4ed204fc00cc62553298901483045022100bd0be6100c4fd8f102ec220e1b053e4c4e2ecca25615490150007b40d314dc3902201a1e0ea266965b43164d9e6576f58fa6726d42883dd1c3996d2925c2e226079601008576a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c820120876475527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae67a9148a486ff2e31d6158bf39e2608864d63fefd09d5b88ac6868f7010000" },
6180
6181                                   { 3,
6182                                   "3044022024cd52e4198c8ae0e414a86d86b5a65ea7450f2eb4e783096736d93395eca5ce022078f0094745b45be4d4b2b04dd5978c9e66ba49109e5704403e84aaf5f387d6be",
6183                                   "3045022100bbfb9d0a946d420807c86e985d636cceb16e71c3694ed186316251a00cbd807202207773223f9a337e145f64673825be9b30d07ef1542c82188b264bedcf7cda78c6",
6184                                   "020000000001010f44041fdfba175987cf4e6135ba2a154e3b7fb96483dc0ed5efc0678e5b6bf103000000000000000001d90d0000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e0500473044022024cd52e4198c8ae0e414a86d86b5a65ea7450f2eb4e783096736d93395eca5ce022078f0094745b45be4d4b2b04dd5978c9e66ba49109e5704403e84aaf5f387d6be01483045022100bbfb9d0a946d420807c86e985d636cceb16e71c3694ed186316251a00cbd807202207773223f9a337e145f64673825be9b30d07ef1542c82188b264bedcf7cda78c6012004040404040404040404040404040404040404040404040404040404040404048a76a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c8201208763a91418bc1a114ccf9c052d3d23e28d3b0a9d1227434288527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae677502f801b175ac686800000000" }
6185                 } );
6186
6187                 // commitment tx with six outputs untrimmed (maximum feerate)
6188                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6189                 chan.feerate_per_kw = 2069;
6190
6191                 test_commitment!("304502210090b96a2498ce0c0f2fadbec2aab278fed54c1a7838df793ec4d2c78d96ec096202204fdd439c50f90d483baa7b68feeef4bd33bc277695405447bcd0bfb2ca34d7bc",
6192                                  "3045022100ad9a9bbbb75d506ca3b716b336ee3cf975dd7834fcf129d7dd188146eb58a8b4022061a759ee417339f7fe2ea1e8deb83abb6a74db31a09b7648a932a639cda23e33",
6193                                  "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", {
6194
6195                                   { 0,
6196                                   "3045022100f33513ee38abf1c582876f921f8fddc06acff48e04515532a32d3938de938ffd02203aa308a2c1863b7d6fdf53159a1465bf2e115c13152546cc5d74483ceaa7f699",
6197                                   "3045022100a637902a5d4c9ba9e7c472a225337d5aac9e2e3f6744f76e237132e7619ba0400220035c60d784a031c0d9f6df66b7eab8726a5c25397399ee4aa960842059eb3f9d",
6198                                   "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" },
6199
6200                                   { 1,
6201                                   "3045022100ce07682cf4b90093c22dc2d9ab2a77ad6803526b655ef857221cc96af5c9e0bf02200f501cee22e7a268af40b555d15a8237c9f36ad67ef1841daf9f6a0267b1e6df",
6202                                   "3045022100e57e46234f8782d3ff7aa593b4f7446fb5316c842e693dc63ee324fd49f6a1c302204a2f7b44c48bd26e1554422afae13153eb94b29d3687b733d18930615fb2db61",
6203                                   "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" },
6204
6205                                   { 2,
6206                                   "3045022100e3e35492e55f82ec0bc2f317ffd7a486d1f7024330fe9743c3559fc39f32ef0c02203d1d4db651fc388a91d5ad8ecdd8e83673063bc8eefe27cfd8c189090e3a23e0",
6207                                   "3044022068613fb1b98eb3aec7f44c5b115b12343c2f066c4277c82b5f873dfe68f37f50022028109b4650f3f528ca4bfe9a467aff2e3e43893b61b5159157119d5d95cf1c18",
6208                                   "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" },
6209
6210                                   { 3,
6211                                   "304402207475aeb0212ef9bf5130b60937817ad88c9a87976988ef1f323f026148cc4a850220739fea17ad3257dcad72e509c73eebe86bee30b178467b9fdab213d631b109df",
6212                                   "3045022100d315522e09e7d53d2a659a79cb67fef56d6c4bddf3f46df6772d0d20a7beb7c8022070bcc17e288607b6a72be0bd83368bb6d53488db266c1cdb4d72214e4f02ac33",
6213                                   "02000000000101adbe717a63fb658add30ada1e6e12ed257637581898abe475c11d7bbcd65bd4d03000000000000000001f2090000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e050047304402207475aeb0212ef9bf5130b60937817ad88c9a87976988ef1f323f026148cc4a850220739fea17ad3257dcad72e509c73eebe86bee30b178467b9fdab213d631b109df01483045022100d315522e09e7d53d2a659a79cb67fef56d6c4bddf3f46df6772d0d20a7beb7c8022070bcc17e288607b6a72be0bd83368bb6d53488db266c1cdb4d72214e4f02ac33012004040404040404040404040404040404040404040404040404040404040404048a76a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c8201208763a91418bc1a114ccf9c052d3d23e28d3b0a9d1227434288527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae677502f801b175ac686800000000" }
6214                 } );
6215
6216                 // commitment tx with five outputs untrimmed (minimum feerate)
6217                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6218                 chan.feerate_per_kw = 2070;
6219
6220                 test_commitment!("304402204ca1ba260dee913d318271d86e10ca0f5883026fb5653155cff600fb40895223022037b145204b7054a40e08bb1fefbd826f827b40838d3e501423bcc57924bcb50c",
6221                                  "3044022001014419b5ba00e083ac4e0a85f19afc848aacac2d483b4b525d15e2ae5adbfe022015ebddad6ee1e72b47cb09f3e78459da5be01ccccd95dceca0e056a00cc773c1",
6222                                  "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", {
6223
6224                                   { 0,
6225                                   "304402205f6b6d12d8d2529fb24f4445630566cf4abbd0f9330ab6c2bdb94222d6a2a0c502202f556258ae6f05b193749e4c541dfcc13b525a5422f6291f073f15617ba8579b",
6226                                   "30440220150b11069454da70caf2492ded9e0065c9a57f25ac2a4c52657b1d15b6c6ed85022068a38833b603c8892717206383611bad210f1cbb4b1f87ea29c6c65b9e1cb3e5",
6227                                   "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" },
6228
6229                                   { 1,
6230                                   "3045022100f960dfb1c9aee7ce1437efa65b523e399383e8149790e05d8fed27ff6e42fe0002202fe8613e062ffe0b0c518cc4101fba1c6de70f64a5bcc7ae663f2efae43b8546",
6231                                   "30450221009a6ed18e6873bc3644332a6ee21c152a5b102821865350df7a8c74451a51f9f2022050d801fb4895d7d7fbf452824c0168347f5c0cbe821cf6a97a63af5b8b2563c6",
6232                                   "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" },
6233
6234                                   { 2,
6235                                   "3045022100ae5fc7717ae684bc1fcf9020854e5dbe9842c9e7472879ac06ff95ac2bb10e4e022057728ada4c00083a3e65493fb5d50a232165948a1a0f530ef63185c2c8c56504",
6236                                   "30440220408ad3009827a8fccf774cb285587686bfb2ed041f89a89453c311ce9c8ee0f902203c7392d9f8306d3a46522a66bd2723a7eb2628cb2d9b34d4c104f1766bf37502",
6237                                   "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" }
6238                 } );
6239
6240                 // commitment tx with five outputs untrimmed (maximum feerate)
6241                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6242                 chan.feerate_per_kw = 2194;
6243
6244                 test_commitment!("304402204bb3d6e279d71d9da414c82de42f1f954267c762b2e2eb8b76bc3be4ea07d4b0022014febc009c5edc8c3fc5d94015de163200f780046f1c293bfed8568f08b70fb3",
6245                                  "3044022072c2e2b1c899b2242656a537dde2892fa3801be0d6df0a87836c550137acde8302201654aa1974d37a829083c3ba15088689f30b56d6a4f6cb14c7bad0ee3116d398",
6246                                  "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", {
6247
6248                                   { 0,
6249                                   "3045022100939726680351a7856c1bc386d4a1f422c7d29bd7b56afc139570f508474e6c40022023175a799ccf44c017fbaadb924c40b2a12115a5b7d0dfd3228df803a2de8450",
6250                                   "304502210099c98c2edeeee6ec0fb5f3bea8b79bb016a2717afa9b5072370f34382de281d302206f5e2980a995e045cf90a547f0752a7ee99d48547bc135258fe7bc07e0154301",
6251                                   "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" },
6252
6253                                   { 1,
6254                                   "3044022021bb883bf324553d085ba2e821cad80c28ef8b303dbead8f98e548783c02d1600220638f9ef2a9bba25869afc923f4b5dc38be3bb459f9efa5d869392d5f7779a4a0",
6255                                   "3045022100fd85bd7697b89c08ec12acc8ba89b23090637d83abd26ca37e01ae93e67c367302202b551fe69386116c47f984aab9c8dfd25d864dcde5d3389cfbef2447a85c4b77",
6256                                   "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" },
6257
6258                                   { 2,
6259                                   "3045022100c9e6f0454aa598b905a35e641a70cc9f67b5f38cc4b00843a041238c4a9f1c4a0220260a2822a62da97e44583e837245995ca2e36781769c52f19e498efbdcca262b",
6260                                   "30450221008a9f2ea24cd455c2b64c1472a5fa83865b0a5f49a62b661801e884cf2849af8302204d44180e50bf6adfcf1c1e581d75af91aba4e28681ce4a5ee5f3cbf65eca10f3",
6261                                   "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" }
6262                 } );
6263
6264                 // commitment tx with four outputs untrimmed (minimum feerate)
6265                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6266                 chan.feerate_per_kw = 2195;
6267
6268                 test_commitment!("304402201a8c1b1f9671cd9e46c7323a104d7047cc48d3ee80d40d4512e0c72b8dc65666022066d7f9a2ce18c9eb22d2739ffcce05721c767f9b607622a31b6ea5793ddce403",
6269                                  "3044022044d592025b610c0d678f65032e87035cdfe89d1598c522cc32524ae8172417c30220749fef9d5b2ae8cdd91ece442ba8809bc891efedae2291e578475f97715d1767",
6270                                  "02000000000101bef67e4e2fb9ddeeb3461973cd4c62abb35050b1add772995b820b584a488489000000000038b02b8004b80b000000000000220020c20b5d1f8584fd90443e7b7b720136174fa4b9333c261d04dbbd012635c0f419a00f0000000000002200208c48d15160397c9731df9bc3b236656efb6665fbfe92b4a6878e88a499f741c4c0c62d0000000000160014cc1b07838e387deacd0e5232e1e8b49f4c29e484b8976a00000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e0400473044022044d592025b610c0d678f65032e87035cdfe89d1598c522cc32524ae8172417c30220749fef9d5b2ae8cdd91ece442ba8809bc891efedae2291e578475f97715d17670147304402201a8c1b1f9671cd9e46c7323a104d7047cc48d3ee80d40d4512e0c72b8dc65666022066d7f9a2ce18c9eb22d2739ffcce05721c767f9b607622a31b6ea5793ddce40301475221023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb21030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c152ae3e195220", {
6271
6272                                   { 0,
6273                                   "3045022100e57b845066a06ee7c2cbfc29eabffe52daa9bf6f6de760066d04df9f9b250e0002202ffb197f0e6e0a77a75a9aff27014bd3de83b7f748d7efef986abe655e1dd50e",
6274                                   "3045022100ecc8c6529d0b2316d046f0f0757c1e1c25a636db168ec4f3aa1b9278df685dc0022067ae6b65e936f1337091f7b18a15935b608c5f2cdddb2f892ed0babfdd376d76",
6275                                   "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" },
6276
6277                                   { 1,
6278                                   "3045022100d193b7ecccad8057571620a0b1ffa6c48e9483311723b59cf536043b20bc51550220546d4bd37b3b101ecda14f6c907af46ec391abce1cd9c7ce22b1a62b534f2f2a",
6279                                   "3044022014d66f11f9cacf923807eba49542076c5fe5cccf252fb08fe98c78ef3ca6ab5402201b290dbe043cc512d9d78de074a5a129b8759bc6a6c546b190d120b690bd6e82",
6280                                   "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" }
6281                 } );
6282
6283                 // commitment tx with four outputs untrimmed (maximum feerate)
6284                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6285                 chan.feerate_per_kw = 3702;
6286
6287                 test_commitment!("304502210092a587aeb777f869e7ff0d7898ea619ee26a3dacd1f3672b945eea600be431100220077ee9eae3528d15251f2a52b607b189820e57a6ccfac8d1af502b132ee40169",
6288                                  "3045022100e5efb73c32d32da2d79702299b6317de6fb24a60476e3855926d78484dd1b3c802203557cb66a42c944ef06e00bcc4da35a5bcb2f185aab0f8e403e519e1d66aaf75",
6289                                  "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", {
6290
6291                                   { 0,
6292                                   "304402206fa54c11f98c3bae1e93df43fc7affeb05b476bf8060c03e29c377c69bc08e8b0220672701cce50d5c379ff45a5d2cfe48ac44973adb066ac32608e21221d869bb89",
6293                                   "304402206e36c683ebf2cb16bcef3d5439cf8b53cd97280a365ed8acd7abb85a8ba5f21c02206e8621edfc2a5766cbc96eb67fd501127ff163eb6b85518a39f7d4974aef126f",
6294                                   "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" },
6295
6296                                   { 1,
6297                                   "3044022057649739b0eb74d541ead0dfdb3d4b2c15aa192720031044c3434c67812e5ca902201e5ede42d960ae551707f4a6b34b09393cf4dee2418507daa022e3550dbb5817",
6298                                   "304402207faad26678c8850e01b4a0696d60841f7305e1832b786110ee9075cb92ed14a30220516ef8ee5dfa80824ea28cbcec0dd95f8b847146257c16960db98507db15ffdc",
6299                                   "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" }
6300                 } );
6301
6302                 // commitment tx with three outputs untrimmed (minimum feerate)
6303                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6304                 chan.feerate_per_kw = 3703;
6305
6306                 test_commitment!("3045022100b495d239772a237ff2cf354b1b11be152fd852704cb184e7356d13f2fb1e5e430220723db5cdb9cbd6ead7bfd3deb419cf41053a932418cbb22a67b581f40bc1f13e",
6307                                  "304402201b736d1773a124c745586217a75bed5f66c05716fbe8c7db4fdb3c3069741cdd02205083f39c321c1bcadfc8d97e3c791a66273d936abac0c6a2fde2ed46019508e1",
6308                                  "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", {
6309
6310                                   { 0,
6311                                   "3045022100c34c61735f93f2e324cc873c3b248111ccf8f6db15d5969583757010d4ad2b4602207867bb919b2ddd6387873e425345c9b7fd18d1d66aba41f3607bc2896ef3c30a",
6312                                   "3045022100988c143e2110067117d2321bdd4bd16ca1734c98b29290d129384af0962b634e02206c1b02478878c5f547018b833986578f90c3e9be669fe5788ad0072a55acbb05",
6313                                   "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" }
6314                 } );
6315
6316                 // commitment tx with three outputs untrimmed (maximum feerate)
6317                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6318                 chan.feerate_per_kw = 4914;
6319
6320                 test_commitment!("3045022100b4b16d5f8cc9fc4c1aff48831e832a0d8990e133978a66e302c133550954a44d022073573ce127e2200d316f6b612803a5c0c97b8d20e1e44dbe2ac0dd2fb8c95244",
6321                                  "3045022100d72638bc6308b88bb6d45861aae83e5b9ff6e10986546e13bce769c70036e2620220320be7c6d66d22f30b9fcd52af66531505b1310ca3b848c19285b38d8a1a8c19",
6322                                  "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", {
6323
6324                                   { 0,
6325                                   "3045022100f43591c156038ba217756006bb3c55f7d113a325cdd7d9303c82115372858d68022016355b5aadf222bc8d12e426c75f4a03423917b2443a103eb2a498a3a2234374",
6326                                   "30440220585dee80fafa264beac535c3c0bb5838ac348b156fdc982f86adc08dfc9bfd250220130abb82f9f295cc9ef423dcfef772fde2acd85d9df48cc538981d26a10a9c10",
6327                                   "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" }
6328                 } );
6329
6330                 // commitment tx with two outputs untrimmed (minimum feerate)
6331                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6332                 chan.feerate_per_kw = 4915;
6333
6334                 test_commitment!("304402203a286936e74870ca1459c700c71202af0381910a6bfab687ef494ef1bc3e02c902202506c362d0e3bee15e802aa729bf378e051644648253513f1c085b264cc2a720",
6335                                  "30450221008a953551f4d67cb4df3037207fc082ddaf6be84d417b0bd14c80aab66f1b01a402207508796dc75034b2dee876fe01dc05a08b019f3e5d689ac8842ade2f1befccf5",
6336                                  "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", {});
6337
6338                 // commitment tx with two outputs untrimmed (maximum feerate)
6339                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6340                 chan.feerate_per_kw = 9651180;
6341
6342                 test_commitment!("304402200a8544eba1d216f5c5e530597665fa9bec56943c0f66d98fc3d028df52d84f7002201e45fa5c6bc3a506cc2553e7d1c0043a9811313fc39c954692c0d47cfce2bbd3",
6343                                  "3045022100e11b638c05c650c2f63a421d36ef8756c5ce82f2184278643520311cdf50aa200220259565fb9c8e4a87ccaf17f27a3b9ca4f20625754a0920d9c6c239d8156a11de",
6344                                  "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", {});
6345
6346                 // commitment tx with one output untrimmed (minimum feerate)
6347                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6348                 chan.feerate_per_kw = 9651181;
6349
6350                 test_commitment!("304402202ade0142008309eb376736575ad58d03e5b115499709c6db0b46e36ff394b492022037b63d78d66404d6504d4c4ac13be346f3d1802928a6d3ad95a6a944227161a2",
6351                                  "304402207e8d51e0c570a5868a78414f4e0cbfaed1106b171b9581542c30718ee4eb95ba02203af84194c97adf98898c9afe2f2ed4a7f8dba05a2dfab28ac9d9c604aa49a379",
6352                                  "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", {});
6353
6354                 // commitment tx with fee greater than funder amount
6355                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
6356                 chan.feerate_per_kw = 9651936;
6357
6358                 test_commitment!("304402202ade0142008309eb376736575ad58d03e5b115499709c6db0b46e36ff394b492022037b63d78d66404d6504d4c4ac13be346f3d1802928a6d3ad95a6a944227161a2",
6359                                  "304402207e8d51e0c570a5868a78414f4e0cbfaed1106b171b9581542c30718ee4eb95ba02203af84194c97adf98898c9afe2f2ed4a7f8dba05a2dfab28ac9d9c604aa49a379",
6360                                  "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", {});
6361
6362                 // commitment tx with 3 htlc outputs, 2 offered having the same amount and preimage
6363                 chan.value_to_self_msat = 7_000_000_000 - 2_000_000;
6364                 chan.feerate_per_kw = 253;
6365                 chan.pending_inbound_htlcs.clear();
6366                 chan.pending_inbound_htlcs.push({
6367                         let mut out = InboundHTLCOutput{
6368                                 htlc_id: 1,
6369                                 amount_msat: 2000000,
6370                                 cltv_expiry: 501,
6371                                 payment_hash: PaymentHash([0; 32]),
6372                                 state: InboundHTLCState::Committed,
6373                         };
6374                         out.payment_hash.0 = Sha256::hash(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()).into_inner();
6375                         out
6376                 });
6377                 chan.pending_outbound_htlcs.clear();
6378                 chan.pending_outbound_htlcs.push({
6379                         let mut out = OutboundHTLCOutput{
6380                                 htlc_id: 6,
6381                                 amount_msat: 5000000,
6382                                 cltv_expiry: 506,
6383                                 payment_hash: PaymentHash([0; 32]),
6384                                 state: OutboundHTLCState::Committed,
6385                                 source: HTLCSource::dummy(),
6386                         };
6387                         out.payment_hash.0 = Sha256::hash(&hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()).into_inner();
6388                         out
6389                 });
6390                 chan.pending_outbound_htlcs.push({
6391                         let mut out = OutboundHTLCOutput{
6392                                 htlc_id: 5,
6393                                 amount_msat: 5000000,
6394                                 cltv_expiry: 505,
6395                                 payment_hash: PaymentHash([0; 32]),
6396                                 state: OutboundHTLCState::Committed,
6397                                 source: HTLCSource::dummy(),
6398                         };
6399                         out.payment_hash.0 = Sha256::hash(&hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()).into_inner();
6400                         out
6401                 });
6402
6403                 test_commitment!("30440220048705bec5288d28b3f29344b8d124853b1af423a568664d2c6f02c8ea886525022060f998a461052a2476b912db426ea2a06700953a241135c7957f2e79bc222df9",
6404                                  "3045022100c4f1d60b6fca9febc8b39de1a31e84c5f7c4b41c97239ef05f4350aa484c6b5e02200c5134ac8b20eb7a29d0dd4a501f6aa8fefb8489171f4cb408bd2a32324ab03f",
6405                                  "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", {
6406
6407                                   { 0,
6408                                   "304502210081cbb94121761d34c189cd4e6a281feea6f585060ad0ba2632e8d6b3c6bb8a6c02201007981bbd16539d63df2805b5568f1f5688cd2a885d04706f50db9b77ba13c6",
6409                                   "304502210090ed76aeb21b53236a598968abc66e2024691d07b62f53ddbeca8f93144af9c602205f873af5a0c10e62690e9aba09740550f194a9dc455ba4c1c23f6cde7704674c",
6410                                   "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" },
6411                                   { 1,
6412                                   "304402201d0f09d2bf7bc245a4f17980e1e9164290df16c70c6a2ff1592f5030d6108581022061e744a7dc151b36bf0aff7a4f1812ba90b8b03633bb979a270d19858fd960c5",
6413                                   "30450221009aef000d2e843a4202c1b1a2bf554abc9a7902bf49b2cb0759bc507456b7ebad02204e7c3d193ede2fd2b4cd6b39f51a920e581e35575e357e44d7b699c40ce61d39",
6414                                   "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" },
6415                                   { 2,
6416                                   "30440220010bf035d5823596e50dce2076a4d9f942d8d28031c9c428b901a02b6b8140de02203250e8e4a08bc5b4ecdca4d0eedf98223e02e3ac1c0206b3a7ffdb374aa21e5f",
6417                                   "30440220073de0067b88e425b3018b30366bfeda0ccb703118ccd3d02ead08c0f53511d002203fac50ac0e4cf8a3af0b4b1b12e801650591f748f8ddf1e089c160f10b69e511",
6418                                   "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" }
6419                 } );
6420         }
6421
6422         #[test]
6423         fn test_per_commitment_secret_gen() {
6424                 // Test vectors from BOLT 3 Appendix D:
6425
6426                 let mut seed = [0; 32];
6427                 seed[0..32].clone_from_slice(&hex::decode("0000000000000000000000000000000000000000000000000000000000000000").unwrap());
6428                 assert_eq!(chan_utils::build_commitment_secret(&seed, 281474976710655),
6429                            hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap()[..]);
6430
6431                 seed[0..32].clone_from_slice(&hex::decode("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF").unwrap());
6432                 assert_eq!(chan_utils::build_commitment_secret(&seed, 281474976710655),
6433                            hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap()[..]);
6434
6435                 assert_eq!(chan_utils::build_commitment_secret(&seed, 0xaaaaaaaaaaa),
6436                            hex::decode("56f4008fb007ca9acf0e15b054d5c9fd12ee06cea347914ddbaed70d1c13a528").unwrap()[..]);
6437
6438                 assert_eq!(chan_utils::build_commitment_secret(&seed, 0x555555555555),
6439                            hex::decode("9015daaeb06dba4ccc05b91b2f73bd54405f2be9f217fbacd3c5ac2e62327d31").unwrap()[..]);
6440
6441                 seed[0..32].clone_from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap());
6442                 assert_eq!(chan_utils::build_commitment_secret(&seed, 1),
6443                            hex::decode("915c75942a26bb3a433a8ce2cb0427c29ec6c1775cfc78328b57f6ba7bfeaa9c").unwrap()[..]);
6444         }
6445
6446         #[test]
6447         fn test_key_derivation() {
6448                 // Test vectors from BOLT 3 Appendix E:
6449                 let secp_ctx = Secp256k1::new();
6450
6451                 let base_secret = SecretKey::from_slice(&hex::decode("000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f").unwrap()[..]).unwrap();
6452                 let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
6453
6454                 let base_point = PublicKey::from_secret_key(&secp_ctx, &base_secret);
6455                 assert_eq!(base_point.serialize()[..], hex::decode("036d6caac248af96f6afa7f904f550253a0f3ef3f5aa2fe6838a95b216691468e2").unwrap()[..]);
6456
6457                 let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
6458                 assert_eq!(per_commitment_point.serialize()[..], hex::decode("025f7117a78150fe2ef97db7cfc83bd57b2e2c0d0dd25eaf467a4a1c2a45ce1486").unwrap()[..]);
6459
6460                 assert_eq!(chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &base_point).unwrap().serialize()[..],
6461                                 hex::decode("0235f2dbfaa89b57ec7b055afe29849ef7ddfeb1cefdb9ebdc43f5494984db29e5").unwrap()[..]);
6462
6463                 assert_eq!(chan_utils::derive_private_key(&secp_ctx, &per_commitment_point, &base_secret).unwrap(),
6464                                 SecretKey::from_slice(&hex::decode("cbced912d3b21bf196a766651e436aff192362621ce317704ea2f75d87e7be0f").unwrap()[..]).unwrap());
6465
6466                 assert_eq!(chan_utils::derive_public_revocation_key(&secp_ctx, &per_commitment_point, &base_point).unwrap().serialize()[..],
6467                                 hex::decode("02916e326636d19c33f13e8c0c3a03dd157f332f3e99c317c141dd865eb01f8ff0").unwrap()[..]);
6468
6469                 assert_eq!(chan_utils::derive_private_revocation_key(&secp_ctx, &per_commitment_secret, &base_secret).unwrap(),
6470                                 SecretKey::from_slice(&hex::decode("d09ffff62ddb2297ab000cc85bcb4283fdeb6aa052affbc9dddcf33b61078110").unwrap()[..]).unwrap());
6471         }
6472 }