a21375483da1e5982966243e2c7f0b2bcf1d6344
[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::{TxIn, TxOut, Transaction, SigHashType};
12 use bitcoin::blockdata::opcodes;
13 use bitcoin::util::bip143;
14 use bitcoin::consensus::encode;
15
16 use bitcoin::hashes::Hash;
17 use bitcoin::hashes::sha256::Hash as Sha256;
18 use bitcoin::hash_types::{Txid, BlockHash, WPubkeyHash};
19
20 use bitcoin::secp256k1::key::{PublicKey,SecretKey};
21 use bitcoin::secp256k1::{Secp256k1,Signature};
22 use bitcoin::secp256k1;
23
24 use ln::{PaymentPreimage, PaymentHash};
25 use ln::features::{ChannelFeatures, InitFeatures};
26 use ln::msgs;
27 use ln::msgs::{DecodeError, OptionalField, DataLossProtect};
28 use ln::channelmanager::{BestBlock, PendingHTLCStatus, HTLCSource, HTLCFailReason, HTLCFailureMsg, PendingHTLCInfo, RAACommitmentOrder, BREAKDOWN_TIMEOUT, MIN_CLTV_EXPIRY_DELTA, MAX_LOCAL_BREAKDOWN_TIMEOUT};
29 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};
30 use ln::chan_utils;
31 use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
32 use chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateStep, HTLC_FAIL_BACK_BUFFER};
33 use chain::transaction::{OutPoint, TransactionData};
34 use chain::keysinterface::{Sign, KeysInterface};
35 use util::transaction_utils;
36 use util::ser::{Readable, ReadableArgs, Writeable, Writer, VecWriter};
37 use util::logger::Logger;
38 use util::errors::APIError;
39 use util::config::{UserConfig,ChannelConfig};
40 use util::scid_utils::scid_from_parts;
41
42 use std;
43 use std::{cmp,mem,fmt};
44 use std::ops::Deref;
45 #[cfg(any(test, feature = "fuzztarget"))]
46 use std::sync::Mutex;
47 use bitcoin::hashes::hex::ToHex;
48 use bitcoin::blockdata::opcodes::all::OP_PUSHBYTES_0;
49
50 #[cfg(test)]
51 pub struct ChannelValueStat {
52         pub value_to_self_msat: u64,
53         pub channel_value_msat: u64,
54         pub channel_reserve_msat: u64,
55         pub pending_outbound_htlcs_amount_msat: u64,
56         pub pending_inbound_htlcs_amount_msat: u64,
57         pub holding_cell_outbound_amount_msat: u64,
58         pub counterparty_max_htlc_value_in_flight_msat: u64, // outgoing
59         pub counterparty_dust_limit_msat: u64,
60 }
61
62 enum InboundHTLCRemovalReason {
63         FailRelay(msgs::OnionErrorPacket),
64         FailMalformed(([u8; 32], u16)),
65         Fulfill(PaymentPreimage),
66 }
67
68 enum InboundHTLCState {
69         /// Offered by remote, to be included in next local commitment tx. I.e., the remote sent an
70         /// update_add_htlc message for this HTLC.
71         RemoteAnnounced(PendingHTLCStatus),
72         /// Included in a received commitment_signed message (implying we've
73         /// revoke_and_ack'd it), but the remote hasn't yet revoked their previous
74         /// state (see the example below). We have not yet included this HTLC in a
75         /// commitment_signed message because we are waiting on the remote's
76         /// aforementioned state revocation. One reason this missing remote RAA
77         /// (revoke_and_ack) blocks us from constructing a commitment_signed message
78         /// is because every time we create a new "state", i.e. every time we sign a
79         /// new commitment tx (see [BOLT #2]), we need a new per_commitment_point,
80         /// which are provided one-at-a-time in each RAA. E.g., the last RAA they
81         /// sent provided the per_commitment_point for our current commitment tx.
82         /// The other reason we should not send a commitment_signed without their RAA
83         /// is because their RAA serves to ACK our previous commitment_signed.
84         ///
85         /// Here's an example of how an HTLC could come to be in this state:
86         /// remote --> update_add_htlc(prev_htlc)   --> local
87         /// remote --> commitment_signed(prev_htlc) --> local
88         /// remote <-- revoke_and_ack               <-- local
89         /// remote <-- commitment_signed(prev_htlc) <-- local
90         /// [note that here, the remote does not respond with a RAA]
91         /// remote --> update_add_htlc(this_htlc)   --> local
92         /// remote --> commitment_signed(prev_htlc, this_htlc) --> local
93         /// Now `this_htlc` will be assigned this state. It's unable to be officially
94         /// accepted, i.e. included in a commitment_signed, because we're missing the
95         /// RAA that provides our next per_commitment_point. The per_commitment_point
96         /// is used to derive commitment keys, which are used to construct the
97         /// signatures in a commitment_signed message.
98         /// Implies AwaitingRemoteRevoke.
99         ///
100         /// [BOLT #2]: https://github.com/lightningnetwork/lightning-rfc/blob/master/02-peer-protocol.md
101         AwaitingRemoteRevokeToAnnounce(PendingHTLCStatus),
102         /// Included in a received commitment_signed message (implying we've revoke_and_ack'd it).
103         /// We have also included this HTLC in our latest commitment_signed and are now just waiting
104         /// on the remote's revoke_and_ack to make this HTLC an irrevocable part of the state of the
105         /// channel (before it can then get forwarded and/or removed).
106         /// Implies AwaitingRemoteRevoke.
107         AwaitingAnnouncedRemoteRevoke(PendingHTLCStatus),
108         Committed,
109         /// Removed by us and a new commitment_signed was sent (if we were AwaitingRemoteRevoke when we
110         /// created it we would have put it in the holding cell instead). When they next revoke_and_ack
111         /// we'll drop it.
112         /// Note that we have to keep an eye on the HTLC until we've received a broadcastable
113         /// commitment transaction without it as otherwise we'll have to force-close the channel to
114         /// claim it before the timeout (obviously doesn't apply to revoked HTLCs that we can't claim
115         /// anyway). That said, ChannelMonitor does this for us (see
116         /// ChannelMonitor::would_broadcast_at_height) so we actually remove the HTLC from our own
117         /// local state before then, once we're sure that the next commitment_signed and
118         /// ChannelMonitor::provide_latest_local_commitment_tx will not include this HTLC.
119         LocalRemoved(InboundHTLCRemovalReason),
120 }
121
122 struct InboundHTLCOutput {
123         htlc_id: u64,
124         amount_msat: u64,
125         cltv_expiry: u32,
126         payment_hash: PaymentHash,
127         state: InboundHTLCState,
128 }
129
130 enum OutboundHTLCState {
131         /// Added by us and included in a commitment_signed (if we were AwaitingRemoteRevoke when we
132         /// created it we would have put it in the holding cell instead). When they next revoke_and_ack
133         /// we will promote to Committed (note that they may not accept it until the next time we
134         /// revoke, but we don't really care about that:
135         ///  * they've revoked, so worst case we can announce an old state and get our (option on)
136         ///    money back (though we won't), and,
137         ///  * we'll send them a revoke when they send a commitment_signed, and since only they're
138         ///    allowed to remove it, the "can only be removed once committed on both sides" requirement
139         ///    doesn't matter to us and it's up to them to enforce it, worst-case they jump ahead but
140         ///    we'll never get out of sync).
141         /// Note that we Box the OnionPacket as it's rather large and we don't want to blow up
142         /// OutboundHTLCOutput's size just for a temporary bit
143         LocalAnnounced(Box<msgs::OnionPacket>),
144         Committed,
145         /// Remote removed this (outbound) HTLC. We're waiting on their commitment_signed to finalize
146         /// the change (though they'll need to revoke before we fail the payment).
147         RemoteRemoved(Option<HTLCFailReason>),
148         /// Remote removed this and sent a commitment_signed (implying we've revoke_and_ack'ed it), but
149         /// the remote side hasn't yet revoked their previous state, which we need them to do before we
150         /// can do any backwards failing. Implies AwaitingRemoteRevoke.
151         /// We also have not yet removed this HTLC in a commitment_signed message, and are waiting on a
152         /// remote revoke_and_ack on a previous state before we can do so.
153         AwaitingRemoteRevokeToRemove(Option<HTLCFailReason>),
154         /// Remote removed this and sent a commitment_signed (implying we've revoke_and_ack'ed it), but
155         /// the remote side hasn't yet revoked their previous state, which we need them to do before we
156         /// can do any backwards failing. Implies AwaitingRemoteRevoke.
157         /// We have removed this HTLC in our latest commitment_signed and are now just waiting on a
158         /// revoke_and_ack to drop completely.
159         AwaitingRemovedRemoteRevoke(Option<HTLCFailReason>),
160 }
161
162 struct OutboundHTLCOutput {
163         htlc_id: u64,
164         amount_msat: u64,
165         cltv_expiry: u32,
166         payment_hash: PaymentHash,
167         state: OutboundHTLCState,
168         source: HTLCSource,
169 }
170
171 /// See AwaitingRemoteRevoke ChannelState for more info
172 enum HTLCUpdateAwaitingACK {
173         AddHTLC { // TODO: Time out if we're getting close to cltv_expiry
174                 // always outbound
175                 amount_msat: u64,
176                 cltv_expiry: u32,
177                 payment_hash: PaymentHash,
178                 source: HTLCSource,
179                 onion_routing_packet: msgs::OnionPacket,
180         },
181         ClaimHTLC {
182                 payment_preimage: PaymentPreimage,
183                 htlc_id: u64,
184         },
185         FailHTLC {
186                 htlc_id: u64,
187                 err_packet: msgs::OnionErrorPacket,
188         },
189 }
190
191 /// There are a few "states" and then a number of flags which can be applied:
192 /// We first move through init with OurInitSent -> TheirInitSent -> FundingCreated -> FundingSent.
193 /// TheirFundingLocked and OurFundingLocked then get set on FundingSent, and when both are set we
194 /// move on to ChannelFunded.
195 /// Note that PeerDisconnected can be set on both ChannelFunded and FundingSent.
196 /// ChannelFunded can then get all remaining flags set on it, until we finish shutdown, then we
197 /// move on to ShutdownComplete, at which point most calls into this channel are disallowed.
198 enum ChannelState {
199         /// Implies we have (or are prepared to) send our open_channel/accept_channel message
200         OurInitSent = 1 << 0,
201         /// Implies we have received their open_channel/accept_channel message
202         TheirInitSent = 1 << 1,
203         /// We have sent funding_created and are awaiting a funding_signed to advance to FundingSent.
204         /// Note that this is nonsense for an inbound channel as we immediately generate funding_signed
205         /// upon receipt of funding_created, so simply skip this state.
206         FundingCreated = 4,
207         /// Set when we have received/sent funding_created and funding_signed and are thus now waiting
208         /// on the funding transaction to confirm. The FundingLocked flags are set to indicate when we
209         /// and our counterparty consider the funding transaction confirmed.
210         FundingSent = 8,
211         /// Flag which can be set on FundingSent to indicate they sent us a funding_locked message.
212         /// Once both TheirFundingLocked and OurFundingLocked are set, state moves on to ChannelFunded.
213         TheirFundingLocked = 1 << 4,
214         /// Flag which can be set on FundingSent to indicate we sent them a funding_locked message.
215         /// Once both TheirFundingLocked and OurFundingLocked are set, state moves on to ChannelFunded.
216         OurFundingLocked = 1 << 5,
217         ChannelFunded = 64,
218         /// Flag which is set on ChannelFunded and FundingSent indicating remote side is considered
219         /// "disconnected" and no updates are allowed until after we've done a channel_reestablish
220         /// dance.
221         PeerDisconnected = 1 << 7,
222         /// Flag which is set on ChannelFunded, FundingCreated, and FundingSent indicating the user has
223         /// told us they failed to update our ChannelMonitor somewhere and we should pause sending any
224         /// outbound messages until they've managed to do so.
225         MonitorUpdateFailed = 1 << 8,
226         /// Flag which implies that we have sent a commitment_signed but are awaiting the responding
227         /// revoke_and_ack message. During this time period, we can't generate new commitment_signed
228         /// messages as then we will be unable to determine which HTLCs they included in their
229         /// revoke_and_ack implicit ACK, so instead we have to hold them away temporarily to be sent
230         /// later.
231         /// Flag is set on ChannelFunded.
232         AwaitingRemoteRevoke = 1 << 9,
233         /// Flag which is set on ChannelFunded or FundingSent after receiving a shutdown message from
234         /// the remote end. If set, they may not add any new HTLCs to the channel, and we are expected
235         /// to respond with our own shutdown message when possible.
236         RemoteShutdownSent = 1 << 10,
237         /// Flag which is set on ChannelFunded or FundingSent after sending a shutdown message. At this
238         /// point, we may not add any new HTLCs to the channel.
239         /// TODO: Investigate some kind of timeout mechanism by which point the remote end must provide
240         /// us their shutdown.
241         LocalShutdownSent = 1 << 11,
242         /// We've successfully negotiated a closing_signed dance. At this point ChannelManager is about
243         /// to drop us, but we store this anyway.
244         ShutdownComplete = 4096,
245 }
246 const BOTH_SIDES_SHUTDOWN_MASK: u32 = ChannelState::LocalShutdownSent as u32 | ChannelState::RemoteShutdownSent as u32;
247 const MULTI_STATE_FLAGS: u32 = BOTH_SIDES_SHUTDOWN_MASK | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32;
248
249 pub const INITIAL_COMMITMENT_NUMBER: u64 = (1 << 48) - 1;
250
251 /// The "channel disabled" bit in channel_update must be set based on whether we are connected to
252 /// our counterparty or not. However, we don't want to announce updates right away to avoid
253 /// spamming the network with updates if the connection is flapping. Instead, we "stage" updates to
254 /// our channel_update message and track the current state here.
255 /// See implementation at [`super::channelmanager::ChannelManager::timer_tick_occurred`].
256 #[derive(Clone, Copy, PartialEq)]
257 pub(super) enum ChannelUpdateStatus {
258         /// We've announced the channel as enabled and are connected to our peer.
259         Enabled,
260         /// Our channel is no longer live, but we haven't announced the channel as disabled yet.
261         DisabledStaged,
262         /// Our channel is live again, but we haven't announced the channel as enabled yet.
263         EnabledStaged,
264         /// We've announced the channel as disabled.
265         Disabled,
266 }
267
268 /// An enum indicating whether the local or remote side offered a given HTLC.
269 enum HTLCInitiator {
270         LocalOffered,
271         RemoteOffered,
272 }
273
274 /// Used when calculating whether we or the remote can afford an additional HTLC.
275 struct HTLCCandidate {
276         amount_msat: u64,
277         origin: HTLCInitiator,
278 }
279
280 impl HTLCCandidate {
281         fn new(amount_msat: u64, origin: HTLCInitiator) -> Self {
282                 Self {
283                         amount_msat,
284                         origin,
285                 }
286         }
287 }
288
289 /// Information needed for constructing an invoice route hint for this channel.
290 #[derive(Clone)]
291 pub struct CounterpartyForwardingInfo {
292         /// Base routing fee in millisatoshis.
293         pub fee_base_msat: u32,
294         /// Amount in millionths of a satoshi the channel will charge per transferred satoshi.
295         pub fee_proportional_millionths: u32,
296         /// The minimum difference in cltv_expiry between an ingoing HTLC and its outgoing counterpart,
297         /// such that the outgoing HTLC is forwardable to this counterparty. See `msgs::ChannelUpdate`'s
298         /// `cltv_expiry_delta` for more details.
299         pub cltv_expiry_delta: u16,
300 }
301
302 // TODO: We should refactor this to be an Inbound/OutboundChannel until initial setup handshaking
303 // has been completed, and then turn into a Channel to get compiler-time enforcement of things like
304 // calling channel_id() before we're set up or things like get_outbound_funding_signed on an
305 // inbound channel.
306 //
307 // Holder designates channel data owned for the benefice of the user client.
308 // Counterparty designates channel data owned by the another channel participant entity.
309 pub(super) struct Channel<Signer: Sign> {
310         config: ChannelConfig,
311
312         user_id: u64,
313
314         channel_id: [u8; 32],
315         channel_state: u32,
316         secp_ctx: Secp256k1<secp256k1::All>,
317         channel_value_satoshis: u64,
318
319         latest_monitor_update_id: u64,
320
321         holder_signer: Signer,
322         shutdown_pubkey: PublicKey,
323         destination_script: Script,
324
325         // Our commitment numbers start at 2^48-1 and count down, whereas the ones used in transaction
326         // generation start at 0 and count up...this simplifies some parts of implementation at the
327         // cost of others, but should really just be changed.
328
329         cur_holder_commitment_transaction_number: u64,
330         cur_counterparty_commitment_transaction_number: u64,
331         value_to_self_msat: u64, // Excluding all pending_htlcs, excluding fees
332         pending_inbound_htlcs: Vec<InboundHTLCOutput>,
333         pending_outbound_htlcs: Vec<OutboundHTLCOutput>,
334         holding_cell_htlc_updates: Vec<HTLCUpdateAwaitingACK>,
335
336         /// When resending CS/RAA messages on channel monitor restoration or on reconnect, we always
337         /// need to ensure we resend them in the order we originally generated them. Note that because
338         /// there can only ever be one in-flight CS and/or one in-flight RAA at any time, it is
339         /// sufficient to simply set this to the opposite of any message we are generating as we
340         /// generate it. ie when we generate a CS, we set this to RAAFirst as, if there is a pending
341         /// in-flight RAA to resend, it will have been the first thing we generated, and thus we should
342         /// send it first.
343         resend_order: RAACommitmentOrder,
344
345         monitor_pending_funding_locked: bool,
346         monitor_pending_revoke_and_ack: bool,
347         monitor_pending_commitment_signed: bool,
348         monitor_pending_forwards: Vec<(PendingHTLCInfo, u64)>,
349         monitor_pending_failures: Vec<(HTLCSource, PaymentHash, HTLCFailReason)>,
350
351         // pending_update_fee is filled when sending and receiving update_fee
352         // For outbound channel, feerate_per_kw is updated with the value from
353         // pending_update_fee when revoke_and_ack is received
354         //
355         // For inbound channel, feerate_per_kw is updated when it receives
356         // commitment_signed and revoke_and_ack is generated
357         // The pending value is kept when another pair of update_fee and commitment_signed
358         // is received during AwaitingRemoteRevoke and relieved when the expected
359         // revoke_and_ack is received and new commitment_signed is generated to be
360         // sent to the funder. Otherwise, the pending value is removed when receiving
361         // commitment_signed.
362         pending_update_fee: Option<u32>,
363         // update_fee() during ChannelState::AwaitingRemoteRevoke is hold in
364         // holdina_cell_update_fee then moved to pending_udpate_fee when revoke_and_ack
365         // is received. holding_cell_update_fee is updated when there are additional
366         // update_fee() during ChannelState::AwaitingRemoteRevoke.
367         holding_cell_update_fee: Option<u32>,
368         next_holder_htlc_id: u64,
369         next_counterparty_htlc_id: u64,
370         update_time_counter: u32,
371         feerate_per_kw: u32,
372
373         #[cfg(debug_assertions)]
374         /// Max to_local and to_remote outputs in a locally-generated commitment transaction
375         holder_max_commitment_tx_output: ::std::sync::Mutex<(u64, u64)>,
376         #[cfg(debug_assertions)]
377         /// Max to_local and to_remote outputs in a remote-generated commitment transaction
378         counterparty_max_commitment_tx_output: ::std::sync::Mutex<(u64, u64)>,
379
380         last_sent_closing_fee: Option<(u32, u64, Signature)>, // (feerate, fee, holder_sig)
381
382         /// The hash of the block in which the funding transaction was included.
383         funding_tx_confirmed_in: Option<BlockHash>,
384         funding_tx_confirmation_height: u32,
385         short_channel_id: Option<u64>,
386
387         counterparty_dust_limit_satoshis: u64,
388         #[cfg(test)]
389         pub(super) holder_dust_limit_satoshis: u64,
390         #[cfg(not(test))]
391         holder_dust_limit_satoshis: u64,
392         #[cfg(test)]
393         pub(super) counterparty_max_htlc_value_in_flight_msat: u64,
394         #[cfg(not(test))]
395         counterparty_max_htlc_value_in_flight_msat: u64,
396         //get_holder_max_htlc_value_in_flight_msat(): u64,
397         /// minimum channel reserve for self to maintain - set by them.
398         counterparty_selected_channel_reserve_satoshis: u64,
399         // get_holder_selected_channel_reserve_satoshis(channel_value_sats: u64): u64
400         counterparty_htlc_minimum_msat: u64,
401         holder_htlc_minimum_msat: u64,
402         #[cfg(test)]
403         pub counterparty_max_accepted_htlcs: u16,
404         #[cfg(not(test))]
405         counterparty_max_accepted_htlcs: u16,
406         //implied by OUR_MAX_HTLCS: max_accepted_htlcs: u16,
407         minimum_depth: u32,
408
409         counterparty_forwarding_info: Option<CounterpartyForwardingInfo>,
410
411         pub(crate) channel_transaction_parameters: ChannelTransactionParameters,
412         funding_transaction: Option<Transaction>,
413
414         counterparty_cur_commitment_point: Option<PublicKey>,
415         counterparty_prev_commitment_point: Option<PublicKey>,
416         counterparty_node_id: PublicKey,
417
418         counterparty_shutdown_scriptpubkey: Option<Script>,
419
420         commitment_secrets: CounterpartyCommitmentSecrets,
421
422         channel_update_status: ChannelUpdateStatus,
423
424         // We save these values so we can make sure `next_local_commit_tx_fee_msat` and
425         // `next_remote_commit_tx_fee_msat` properly predict what the next commitment transaction fee will
426         // be, by comparing the cached values to the fee of the tranaction generated by
427         // `build_commitment_transaction`.
428         #[cfg(any(test, feature = "fuzztarget"))]
429         next_local_commitment_tx_fee_info_cached: Mutex<Option<CommitmentTxInfoCached>>,
430         #[cfg(any(test, feature = "fuzztarget"))]
431         next_remote_commitment_tx_fee_info_cached: Mutex<Option<CommitmentTxInfoCached>>,
432 }
433
434 #[cfg(any(test, feature = "fuzztarget"))]
435 struct CommitmentTxInfoCached {
436         fee: u64,
437         total_pending_htlcs: usize,
438         next_holder_htlc_id: u64,
439         next_counterparty_htlc_id: u64,
440         feerate: u32,
441 }
442
443 pub const OUR_MAX_HTLCS: u16 = 50; //TODO
444 const SPENDING_INPUT_FOR_A_OUTPUT_WEIGHT: u64 = 79; // prevout: 36, nSequence: 4, script len: 1, witness lengths: (3+1)/4, sig: 73/4, if-selector: 1, redeemScript: (6 ops + 2*33 pubkeys + 1*2 delay)/4
445
446 #[cfg(not(test))]
447 const COMMITMENT_TX_BASE_WEIGHT: u64 = 724;
448 #[cfg(test)]
449 pub const COMMITMENT_TX_BASE_WEIGHT: u64 = 724;
450 #[cfg(not(test))]
451 const COMMITMENT_TX_WEIGHT_PER_HTLC: u64 = 172;
452 #[cfg(test)]
453 pub const COMMITMENT_TX_WEIGHT_PER_HTLC: u64 = 172;
454
455 /// Maximmum `funding_satoshis` value, according to the BOLT #2 specification
456 /// it's 2^24.
457 pub const MAX_FUNDING_SATOSHIS: u64 = 1 << 24;
458
459 /// Maximum counterparty `dust_limit_satoshis` allowed. 2 * standard dust threshold on p2wsh output
460 /// Scales up on Bitcoin Core's proceeding policy with dust outputs. A typical p2wsh output is 43
461 /// bytes to which Core's `GetDustThreshold()` sums up a minimal spend of 67 bytes (even if
462 /// a p2wsh witnessScript might be *effectively* smaller), `dustRelayFee` is set to 3000sat/kb, thus
463 /// 110 * 3000 / 1000 = 330. Per-protocol rules, all time-sensitive outputs are p2wsh, a value of
464 /// 330 sats is the lower bound desired to ensure good propagation of transactions. We give a bit
465 /// of margin to our counterparty and pick up 660 satoshis as an accepted `dust_limit_satoshis`
466 /// upper bound to avoid negotiation conflicts with other implementations.
467 pub const MAX_DUST_LIMIT_SATOSHIS: u64 = 2 * 330;
468
469 /// A typical p2wsh output is 43 bytes to which Core's `GetDustThreshold()` sums up a minimal
470 /// spend of 67 bytes (even if a p2wsh witnessScript might be *effectively* smaller), `dustRelayFee`
471 /// is set to 3000sat/kb, thus 110 * 3000 / 1000 = 330. Per-protocol rules, all time-sensitive outputs
472 /// are p2wsh, a value of 330 sats is the lower bound desired to ensure good propagation of transactions.
473 pub const MIN_DUST_LIMIT_SATOSHIS: u64 = 330;
474
475 /// Used to return a simple Error back to ChannelManager. Will get converted to a
476 /// msgs::ErrorAction::SendErrorMessage or msgs::ErrorAction::IgnoreError as appropriate with our
477 /// channel_id in ChannelManager.
478 pub(super) enum ChannelError {
479         Ignore(String),
480         Close(String),
481         CloseDelayBroadcast(String),
482 }
483
484 impl fmt::Debug for ChannelError {
485         fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
486                 match self {
487                         &ChannelError::Ignore(ref e) => write!(f, "Ignore : {}", e),
488                         &ChannelError::Close(ref e) => write!(f, "Close : {}", e),
489                         &ChannelError::CloseDelayBroadcast(ref e) => write!(f, "CloseDelayBroadcast : {}", e)
490                 }
491         }
492 }
493
494 macro_rules! secp_check {
495         ($res: expr, $err: expr) => {
496                 match $res {
497                         Ok(thing) => thing,
498                         Err(_) => return Err(ChannelError::Close($err)),
499                 }
500         };
501 }
502
503 impl<Signer: Sign> Channel<Signer> {
504         // Convert constants + channel value to limits:
505         fn get_holder_max_htlc_value_in_flight_msat(channel_value_satoshis: u64) -> u64 {
506                 channel_value_satoshis * 1000 / 10 //TODO
507         }
508
509         /// Returns a minimum channel reserve value the remote needs to maintain,
510         /// required by us.
511         ///
512         /// Guaranteed to return a value no larger than channel_value_satoshis
513         pub(crate) fn get_holder_selected_channel_reserve_satoshis(channel_value_satoshis: u64) -> u64 {
514                 let (q, _) = channel_value_satoshis.overflowing_div(100);
515                 cmp::min(channel_value_satoshis, cmp::max(q, 1000)) //TODO
516         }
517
518         // Constructors:
519         pub fn new_outbound<K: Deref, F: Deref>(fee_estimator: &F, keys_provider: &K, counterparty_node_id: PublicKey, channel_value_satoshis: u64, push_msat: u64, user_id: u64, config: &UserConfig) -> Result<Channel<Signer>, APIError>
520         where K::Target: KeysInterface<Signer = Signer>,
521               F::Target: FeeEstimator,
522         {
523                 let holder_selected_contest_delay = config.own_channel_config.our_to_self_delay;
524                 let holder_signer = keys_provider.get_channel_signer(false, channel_value_satoshis);
525                 let pubkeys = holder_signer.pubkeys().clone();
526
527                 if channel_value_satoshis >= MAX_FUNDING_SATOSHIS {
528                         return Err(APIError::APIMisuseError{err: format!("funding_value must be smaller than {}, it was {}", MAX_FUNDING_SATOSHIS, channel_value_satoshis)});
529                 }
530                 let channel_value_msat = channel_value_satoshis * 1000;
531                 if push_msat > channel_value_msat {
532                         return Err(APIError::APIMisuseError { err: format!("Push value ({}) was larger than channel_value ({})", push_msat, channel_value_msat) });
533                 }
534                 if holder_selected_contest_delay < BREAKDOWN_TIMEOUT {
535                         return Err(APIError::APIMisuseError {err: format!("Configured with an unreasonable our_to_self_delay ({}) putting user funds at risks", holder_selected_contest_delay)});
536                 }
537                 let holder_selected_channel_reserve_satoshis = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(channel_value_satoshis);
538                 if holder_selected_channel_reserve_satoshis < MIN_DUST_LIMIT_SATOSHIS {
539                         return Err(APIError::APIMisuseError { err: format!("Holder selected channel  reserve below implemention limit dust_limit_satoshis {}", holder_selected_channel_reserve_satoshis) });
540                 }
541
542                 let feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
543
544                 let mut secp_ctx = Secp256k1::new();
545                 secp_ctx.seeded_randomize(&keys_provider.get_secure_random_bytes());
546
547                 Ok(Channel {
548                         user_id,
549                         config: config.channel_options.clone(),
550
551                         channel_id: keys_provider.get_secure_random_bytes(),
552                         channel_state: ChannelState::OurInitSent as u32,
553                         secp_ctx,
554                         channel_value_satoshis,
555
556                         latest_monitor_update_id: 0,
557
558                         holder_signer,
559                         shutdown_pubkey: keys_provider.get_shutdown_pubkey(),
560                         destination_script: keys_provider.get_destination_script(),
561
562                         cur_holder_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
563                         cur_counterparty_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
564                         value_to_self_msat: channel_value_satoshis * 1000 - push_msat,
565
566                         pending_inbound_htlcs: Vec::new(),
567                         pending_outbound_htlcs: Vec::new(),
568                         holding_cell_htlc_updates: Vec::new(),
569                         pending_update_fee: None,
570                         holding_cell_update_fee: None,
571                         next_holder_htlc_id: 0,
572                         next_counterparty_htlc_id: 0,
573                         update_time_counter: 1,
574
575                         resend_order: RAACommitmentOrder::CommitmentFirst,
576
577                         monitor_pending_funding_locked: false,
578                         monitor_pending_revoke_and_ack: false,
579                         monitor_pending_commitment_signed: false,
580                         monitor_pending_forwards: Vec::new(),
581                         monitor_pending_failures: Vec::new(),
582
583                         #[cfg(debug_assertions)]
584                         holder_max_commitment_tx_output: ::std::sync::Mutex::new((channel_value_satoshis * 1000 - push_msat, push_msat)),
585                         #[cfg(debug_assertions)]
586                         counterparty_max_commitment_tx_output: ::std::sync::Mutex::new((channel_value_satoshis * 1000 - push_msat, push_msat)),
587
588                         last_sent_closing_fee: None,
589
590                         funding_tx_confirmed_in: None,
591                         funding_tx_confirmation_height: 0,
592                         short_channel_id: None,
593
594                         feerate_per_kw: feerate,
595                         counterparty_dust_limit_satoshis: 0,
596                         holder_dust_limit_satoshis: MIN_DUST_LIMIT_SATOSHIS,
597                         counterparty_max_htlc_value_in_flight_msat: 0,
598                         counterparty_selected_channel_reserve_satoshis: 0,
599                         counterparty_htlc_minimum_msat: 0,
600                         holder_htlc_minimum_msat: if config.own_channel_config.our_htlc_minimum_msat == 0 { 1 } else { config.own_channel_config.our_htlc_minimum_msat },
601                         counterparty_max_accepted_htlcs: 0,
602                         minimum_depth: 0, // Filled in in accept_channel
603
604                         counterparty_forwarding_info: None,
605
606                         channel_transaction_parameters: ChannelTransactionParameters {
607                                 holder_pubkeys: pubkeys,
608                                 holder_selected_contest_delay: config.own_channel_config.our_to_self_delay,
609                                 is_outbound_from_holder: true,
610                                 counterparty_parameters: None,
611                                 funding_outpoint: None
612                         },
613                         funding_transaction: None,
614
615                         counterparty_cur_commitment_point: None,
616                         counterparty_prev_commitment_point: None,
617                         counterparty_node_id,
618
619                         counterparty_shutdown_scriptpubkey: None,
620
621                         commitment_secrets: CounterpartyCommitmentSecrets::new(),
622
623                         channel_update_status: ChannelUpdateStatus::Enabled,
624
625                         #[cfg(any(test, feature = "fuzztarget"))]
626                         next_local_commitment_tx_fee_info_cached: Mutex::new(None),
627                         #[cfg(any(test, feature = "fuzztarget"))]
628                         next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
629                 })
630         }
631
632         fn check_remote_fee<F: Deref>(fee_estimator: &F, feerate_per_kw: u32) -> Result<(), ChannelError>
633                 where F::Target: FeeEstimator
634         {
635                 let lower_limit = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
636                 if feerate_per_kw < lower_limit {
637                         return Err(ChannelError::Close(format!("Peer's feerate much too low. Actual: {}. Our expected lower limit: {}", feerate_per_kw, lower_limit)));
638                 }
639                 let upper_limit = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::HighPriority) as u64  * 2;
640                 if feerate_per_kw as u64 > upper_limit {
641                         return Err(ChannelError::Close(format!("Peer's feerate much too high. Actual: {}. Our expected upper limit: {}", feerate_per_kw, upper_limit)));
642                 }
643                 Ok(())
644         }
645
646         /// Creates a new channel from a remote sides' request for one.
647         /// Assumes chain_hash has already been checked and corresponds with what we expect!
648         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>
649                 where K::Target: KeysInterface<Signer = Signer>,
650           F::Target: FeeEstimator
651         {
652                 let holder_signer = keys_provider.get_channel_signer(true, msg.funding_satoshis);
653                 let pubkeys = holder_signer.pubkeys().clone();
654                 let counterparty_pubkeys = ChannelPublicKeys {
655                         funding_pubkey: msg.funding_pubkey,
656                         revocation_basepoint: msg.revocation_basepoint,
657                         payment_point: msg.payment_point,
658                         delayed_payment_basepoint: msg.delayed_payment_basepoint,
659                         htlc_basepoint: msg.htlc_basepoint
660                 };
661                 let mut local_config = (*config).channel_options.clone();
662
663                 if config.own_channel_config.our_to_self_delay < BREAKDOWN_TIMEOUT {
664                         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)));
665                 }
666
667                 // Check sanity of message fields:
668                 if msg.funding_satoshis >= MAX_FUNDING_SATOSHIS {
669                         return Err(ChannelError::Close(format!("Funding must be smaller than {}. It was {}", MAX_FUNDING_SATOSHIS, msg.funding_satoshis)));
670                 }
671                 if msg.channel_reserve_satoshis > msg.funding_satoshis {
672                         return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must be not greater than funding_satoshis: {}", msg.channel_reserve_satoshis, msg.funding_satoshis)));
673                 }
674                 let funding_value = (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000;
675                 if msg.push_msat > funding_value {
676                         return Err(ChannelError::Close(format!("push_msat {} was larger than funding value {}", msg.push_msat, funding_value)));
677                 }
678                 if msg.dust_limit_satoshis > msg.funding_satoshis {
679                         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)));
680                 }
681                 if msg.dust_limit_satoshis > msg.channel_reserve_satoshis {
682                         return Err(ChannelError::Close(format!("Bogus; channel reserve ({}) is less than dust limit ({})", msg.channel_reserve_satoshis, msg.dust_limit_satoshis)));
683                 }
684                 let full_channel_value_msat = (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000;
685                 if msg.htlc_minimum_msat >= full_channel_value_msat {
686                         return Err(ChannelError::Close(format!("Minimum htlc value ({}) was larger than full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat)));
687                 }
688                 Channel::<Signer>::check_remote_fee(fee_estimator, msg.feerate_per_kw)?;
689
690                 let max_counterparty_selected_contest_delay = u16::min(config.peer_channel_config_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
691                 if msg.to_self_delay > max_counterparty_selected_contest_delay {
692                         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)));
693                 }
694                 if msg.max_accepted_htlcs < 1 {
695                         return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel".to_owned()));
696                 }
697                 if msg.max_accepted_htlcs > MAX_HTLCS {
698                         return Err(ChannelError::Close(format!("max_accepted_htlcs was {}. It must not be larger than {}", msg.max_accepted_htlcs, MAX_HTLCS)));
699                 }
700
701                 // Now check against optional parameters as set by config...
702                 if msg.funding_satoshis < config.peer_channel_config_limits.min_funding_satoshis {
703                         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)));
704                 }
705                 if msg.htlc_minimum_msat > config.peer_channel_config_limits.max_htlc_minimum_msat {
706                         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)));
707                 }
708                 if msg.max_htlc_value_in_flight_msat < config.peer_channel_config_limits.min_max_htlc_value_in_flight_msat {
709                         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)));
710                 }
711                 if msg.channel_reserve_satoshis > config.peer_channel_config_limits.max_channel_reserve_satoshis {
712                         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)));
713                 }
714                 if msg.max_accepted_htlcs < config.peer_channel_config_limits.min_max_accepted_htlcs {
715                         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)));
716                 }
717                 if msg.dust_limit_satoshis < MIN_DUST_LIMIT_SATOSHIS {
718                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the implementation limit ({})", msg.dust_limit_satoshis, MIN_DUST_LIMIT_SATOSHIS)));
719                 }
720                 if msg.dust_limit_satoshis >  MAX_DUST_LIMIT_SATOSHIS {
721                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the implementation limit ({})", msg.dust_limit_satoshis, MAX_DUST_LIMIT_SATOSHIS)));
722                 }
723
724                 // Convert things into internal flags and prep our state:
725
726                 let announce = if (msg.channel_flags & 1) == 1 { true } else { false };
727                 if config.peer_channel_config_limits.force_announced_channel_preference {
728                         if local_config.announced_channel != announce {
729                                 return Err(ChannelError::Close("Peer tried to open channel but their announcement preference is different from ours".to_owned()));
730                         }
731                 }
732                 // we either accept their preference or the preferences match
733                 local_config.announced_channel = announce;
734
735                 let background_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
736
737                 let holder_selected_channel_reserve_satoshis = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(msg.funding_satoshis);
738                 if holder_selected_channel_reserve_satoshis < MIN_DUST_LIMIT_SATOSHIS {
739                         return Err(ChannelError::Close(format!("Suitable channel reserve not found. remote_channel_reserve was ({}). dust_limit_satoshis is ({}).", holder_selected_channel_reserve_satoshis, MIN_DUST_LIMIT_SATOSHIS)));
740                 }
741                 if msg.channel_reserve_satoshis < MIN_DUST_LIMIT_SATOSHIS {
742                         return Err(ChannelError::Close(format!("channel_reserve_satoshis ({}) is smaller than our dust limit ({})", msg.channel_reserve_satoshis, MIN_DUST_LIMIT_SATOSHIS)));
743                 }
744                 if holder_selected_channel_reserve_satoshis < msg.dust_limit_satoshis {
745                         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)));
746                 }
747
748                 // check if the funder's amount for the initial commitment tx is sufficient
749                 // for full fee payment
750                 let funders_amount_msat = msg.funding_satoshis * 1000 - msg.push_msat;
751                 let lower_limit = background_feerate as u64 * COMMITMENT_TX_BASE_WEIGHT;
752                 if funders_amount_msat < lower_limit {
753                         return Err(ChannelError::Close(format!("Insufficient funding amount ({}) for initial commitment. Must be at least {}", funders_amount_msat, lower_limit)));
754                 }
755
756                 let to_local_msat = msg.push_msat;
757                 let to_remote_msat = funders_amount_msat - background_feerate as u64 * COMMITMENT_TX_BASE_WEIGHT;
758                 if to_local_msat <= msg.channel_reserve_satoshis * 1000 && to_remote_msat <= holder_selected_channel_reserve_satoshis * 1000 {
759                         return Err(ChannelError::Close("Insufficient funding amount for initial commitment".to_owned()));
760                 }
761
762                 let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() {
763                         match &msg.shutdown_scriptpubkey {
764                                 &OptionalField::Present(ref script) => {
765                                         // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything
766                                         if script.len() == 0 {
767                                                 None
768                                         // Peer is signaling upfront_shutdown and has provided a non-accepted scriptpubkey format. Fail the channel
769                                         } else if is_unsupported_shutdown_script(&their_features, script) {
770                                                 return Err(ChannelError::Close(format!("Peer is signaling upfront_shutdown but has provided a non-accepted scriptpubkey format. script: ({})", script.to_bytes().to_hex())));
771                                         } else {
772                                                 Some(script.clone())
773                                         }
774                                 },
775                                 // 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
776                                 &OptionalField::Absent => {
777                                         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()));
778                                 }
779                         }
780                 } else { None };
781
782                 let mut secp_ctx = Secp256k1::new();
783                 secp_ctx.seeded_randomize(&keys_provider.get_secure_random_bytes());
784
785                 let chan = Channel {
786                         user_id,
787                         config: local_config,
788
789                         channel_id: msg.temporary_channel_id,
790                         channel_state: (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32),
791                         secp_ctx,
792
793                         latest_monitor_update_id: 0,
794
795                         holder_signer,
796                         shutdown_pubkey: keys_provider.get_shutdown_pubkey(),
797                         destination_script: keys_provider.get_destination_script(),
798
799                         cur_holder_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
800                         cur_counterparty_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
801                         value_to_self_msat: msg.push_msat,
802
803                         pending_inbound_htlcs: Vec::new(),
804                         pending_outbound_htlcs: Vec::new(),
805                         holding_cell_htlc_updates: Vec::new(),
806                         pending_update_fee: None,
807                         holding_cell_update_fee: None,
808                         next_holder_htlc_id: 0,
809                         next_counterparty_htlc_id: 0,
810                         update_time_counter: 1,
811
812                         resend_order: RAACommitmentOrder::CommitmentFirst,
813
814                         monitor_pending_funding_locked: false,
815                         monitor_pending_revoke_and_ack: false,
816                         monitor_pending_commitment_signed: false,
817                         monitor_pending_forwards: Vec::new(),
818                         monitor_pending_failures: Vec::new(),
819
820                         #[cfg(debug_assertions)]
821                         holder_max_commitment_tx_output: ::std::sync::Mutex::new((msg.push_msat, msg.funding_satoshis * 1000 - msg.push_msat)),
822                         #[cfg(debug_assertions)]
823                         counterparty_max_commitment_tx_output: ::std::sync::Mutex::new((msg.push_msat, msg.funding_satoshis * 1000 - msg.push_msat)),
824
825                         last_sent_closing_fee: None,
826
827                         funding_tx_confirmed_in: None,
828                         funding_tx_confirmation_height: 0,
829                         short_channel_id: None,
830
831                         feerate_per_kw: msg.feerate_per_kw,
832                         channel_value_satoshis: msg.funding_satoshis,
833                         counterparty_dust_limit_satoshis: msg.dust_limit_satoshis,
834                         holder_dust_limit_satoshis: MIN_DUST_LIMIT_SATOSHIS,
835                         counterparty_max_htlc_value_in_flight_msat: cmp::min(msg.max_htlc_value_in_flight_msat, msg.funding_satoshis * 1000),
836                         counterparty_selected_channel_reserve_satoshis: msg.channel_reserve_satoshis,
837                         counterparty_htlc_minimum_msat: msg.htlc_minimum_msat,
838                         holder_htlc_minimum_msat: if config.own_channel_config.our_htlc_minimum_msat == 0 { 1 } else { config.own_channel_config.our_htlc_minimum_msat },
839                         counterparty_max_accepted_htlcs: msg.max_accepted_htlcs,
840                         minimum_depth: config.own_channel_config.minimum_depth,
841
842                         counterparty_forwarding_info: None,
843
844                         channel_transaction_parameters: ChannelTransactionParameters {
845                                 holder_pubkeys: pubkeys,
846                                 holder_selected_contest_delay: config.own_channel_config.our_to_self_delay,
847                                 is_outbound_from_holder: false,
848                                 counterparty_parameters: Some(CounterpartyChannelTransactionParameters {
849                                         selected_contest_delay: msg.to_self_delay,
850                                         pubkeys: counterparty_pubkeys,
851                                 }),
852                                 funding_outpoint: None
853                         },
854                         funding_transaction: None,
855
856                         counterparty_cur_commitment_point: Some(msg.first_per_commitment_point),
857                         counterparty_prev_commitment_point: None,
858                         counterparty_node_id,
859
860                         counterparty_shutdown_scriptpubkey,
861
862                         commitment_secrets: CounterpartyCommitmentSecrets::new(),
863
864                         channel_update_status: ChannelUpdateStatus::Enabled,
865
866                         #[cfg(any(test, feature = "fuzztarget"))]
867                         next_local_commitment_tx_fee_info_cached: Mutex::new(None),
868                         #[cfg(any(test, feature = "fuzztarget"))]
869                         next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
870                 };
871
872                 Ok(chan)
873         }
874
875         /// Transaction nomenclature is somewhat confusing here as there are many different cases - a
876         /// transaction is referred to as "a's transaction" implying that a will be able to broadcast
877         /// the transaction. Thus, b will generally be sending a signature over such a transaction to
878         /// a, and a can revoke the transaction by providing b the relevant per_commitment_secret. As
879         /// such, a transaction is generally the result of b increasing the amount paid to a (or adding
880         /// an HTLC to a).
881         /// @local is used only to convert relevant internal structures which refer to remote vs local
882         /// to decide value of outputs and direction of HTLCs.
883         /// @generated_by_local is used to determine *which* HTLCs to include - noting that the HTLC
884         /// state may indicate that one peer has informed the other that they'd like to add an HTLC but
885         /// have not yet committed it. Such HTLCs will only be included in transactions which are being
886         /// generated by the peer which proposed adding the HTLCs, and thus we need to understand both
887         /// which peer generated this transaction and "to whom" this transaction flows.
888         /// Returns (the transaction info, the number of HTLC outputs which were present in the
889         /// transaction, the list of HTLCs which were not ignored when building the transaction).
890         /// Note that below-dust HTLCs are included in the third return value, but not the second, and
891         /// sources are provided only for outbound HTLCs in the third return value.
892         #[inline]
893         fn build_commitment_transaction<L: Deref>(&self, commitment_number: u64, keys: &TxCreationKeys, local: bool, generated_by_local: bool, feerate_per_kw: u32, logger: &L) -> (CommitmentTransaction, usize, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>) where L::Target: Logger {
894                 let mut included_dust_htlcs: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::new();
895                 let num_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len();
896                 let mut included_non_dust_htlcs: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::with_capacity(num_htlcs);
897
898                 let broadcaster_dust_limit_satoshis = if local { self.holder_dust_limit_satoshis } else { self.counterparty_dust_limit_satoshis };
899                 let mut remote_htlc_total_msat = 0;
900                 let mut local_htlc_total_msat = 0;
901                 let mut value_to_self_msat_offset = 0;
902
903                 log_trace!(logger, "Building commitment transaction number {} (really {} xor {}) for {}, generated by {} with fee {}...", commitment_number, (INITIAL_COMMITMENT_NUMBER - commitment_number), get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound()), if local { "us" } else { "remote" }, if generated_by_local { "us" } else { "remote" }, feerate_per_kw);
904
905                 macro_rules! get_htlc_in_commitment {
906                         ($htlc: expr, $offered: expr) => {
907                                 HTLCOutputInCommitment {
908                                         offered: $offered,
909                                         amount_msat: $htlc.amount_msat,
910                                         cltv_expiry: $htlc.cltv_expiry,
911                                         payment_hash: $htlc.payment_hash,
912                                         transaction_output_index: None
913                                 }
914                         }
915                 }
916
917                 macro_rules! add_htlc_output {
918                         ($htlc: expr, $outbound: expr, $source: expr, $state_name: expr) => {
919                                 if $outbound == local { // "offered HTLC output"
920                                         let htlc_in_tx = get_htlc_in_commitment!($htlc, true);
921                                         if $htlc.amount_msat / 1000 >= broadcaster_dust_limit_satoshis + (feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) {
922                                                 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);
923                                                 included_non_dust_htlcs.push((htlc_in_tx, $source));
924                                         } else {
925                                                 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);
926                                                 included_dust_htlcs.push((htlc_in_tx, $source));
927                                         }
928                                 } else {
929                                         let htlc_in_tx = get_htlc_in_commitment!($htlc, false);
930                                         if $htlc.amount_msat / 1000 >= broadcaster_dust_limit_satoshis + (feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) {
931                                                 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);
932                                                 included_non_dust_htlcs.push((htlc_in_tx, $source));
933                                         } else {
934                                                 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);
935                                                 included_dust_htlcs.push((htlc_in_tx, $source));
936                                         }
937                                 }
938                         }
939                 }
940
941                 for ref htlc in self.pending_inbound_htlcs.iter() {
942                         let (include, state_name) = match htlc.state {
943                                 InboundHTLCState::RemoteAnnounced(_) => (!generated_by_local, "RemoteAnnounced"),
944                                 InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_) => (!generated_by_local, "AwaitingRemoteRevokeToAnnounce"),
945                                 InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) => (true, "AwaitingAnnouncedRemoteRevoke"),
946                                 InboundHTLCState::Committed => (true, "Committed"),
947                                 InboundHTLCState::LocalRemoved(_) => (!generated_by_local, "LocalRemoved"),
948                         };
949
950                         if include {
951                                 add_htlc_output!(htlc, false, None, state_name);
952                                 remote_htlc_total_msat += htlc.amount_msat;
953                         } else {
954                                 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);
955                                 match &htlc.state {
956                                         &InboundHTLCState::LocalRemoved(ref reason) => {
957                                                 if generated_by_local {
958                                                         if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
959                                                                 value_to_self_msat_offset += htlc.amount_msat as i64;
960                                                         }
961                                                 }
962                                         },
963                                         _ => {},
964                                 }
965                         }
966                 }
967
968                 for ref htlc in self.pending_outbound_htlcs.iter() {
969                         let (include, state_name) = match htlc.state {
970                                 OutboundHTLCState::LocalAnnounced(_) => (generated_by_local, "LocalAnnounced"),
971                                 OutboundHTLCState::Committed => (true, "Committed"),
972                                 OutboundHTLCState::RemoteRemoved(_) => (generated_by_local, "RemoteRemoved"),
973                                 OutboundHTLCState::AwaitingRemoteRevokeToRemove(_) => (generated_by_local, "AwaitingRemoteRevokeToRemove"),
974                                 OutboundHTLCState::AwaitingRemovedRemoteRevoke(_) => (false, "AwaitingRemovedRemoteRevoke"),
975                         };
976
977                         if include {
978                                 add_htlc_output!(htlc, true, Some(&htlc.source), state_name);
979                                 local_htlc_total_msat += htlc.amount_msat;
980                         } else {
981                                 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);
982                                 match htlc.state {
983                                         OutboundHTLCState::AwaitingRemoteRevokeToRemove(None)|OutboundHTLCState::AwaitingRemovedRemoteRevoke(None) => {
984                                                 value_to_self_msat_offset -= htlc.amount_msat as i64;
985                                         },
986                                         OutboundHTLCState::RemoteRemoved(None) => {
987                                                 if !generated_by_local {
988                                                         value_to_self_msat_offset -= htlc.amount_msat as i64;
989                                                 }
990                                         },
991                                         _ => {},
992                                 }
993                         }
994                 }
995
996                 let value_to_self_msat: i64 = (self.value_to_self_msat - local_htlc_total_msat) as i64 + value_to_self_msat_offset;
997                 assert!(value_to_self_msat >= 0);
998                 // Note that in case they have several just-awaiting-last-RAA fulfills in-progress (ie
999                 // AwaitingRemoteRevokeToRemove or AwaitingRemovedRemoteRevoke) we may have allowed them to
1000                 // "violate" their reserve value by couting those against it. Thus, we have to convert
1001                 // everything to i64 before subtracting as otherwise we can overflow.
1002                 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;
1003                 assert!(value_to_remote_msat >= 0);
1004
1005                 #[cfg(debug_assertions)]
1006                 {
1007                         // Make sure that the to_self/to_remote is always either past the appropriate
1008                         // channel_reserve *or* it is making progress towards it.
1009                         let mut broadcaster_max_commitment_tx_output = if generated_by_local {
1010                                 self.holder_max_commitment_tx_output.lock().unwrap()
1011                         } else {
1012                                 self.counterparty_max_commitment_tx_output.lock().unwrap()
1013                         };
1014                         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 as i64);
1015                         broadcaster_max_commitment_tx_output.0 = cmp::max(broadcaster_max_commitment_tx_output.0, value_to_self_msat as u64);
1016                         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);
1017                         broadcaster_max_commitment_tx_output.1 = cmp::max(broadcaster_max_commitment_tx_output.1, value_to_remote_msat as u64);
1018                 }
1019
1020                 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;
1021                 let (value_to_self, value_to_remote) = if self.is_outbound() {
1022                         (value_to_self_msat / 1000 - total_fee as i64, value_to_remote_msat / 1000)
1023                 } else {
1024                         (value_to_self_msat / 1000, value_to_remote_msat / 1000 - total_fee as i64)
1025                 };
1026
1027                 let mut value_to_a = if local { value_to_self } else { value_to_remote };
1028                 let mut value_to_b = if local { value_to_remote } else { value_to_self };
1029
1030                 if value_to_a >= (broadcaster_dust_limit_satoshis as i64) {
1031                         log_trace!(logger, "   ...including {} output with value {}", if local { "to_local" } else { "to_remote" }, value_to_a);
1032                 } else {
1033                         value_to_a = 0;
1034                 }
1035
1036                 if value_to_b >= (broadcaster_dust_limit_satoshis as i64) {
1037                         log_trace!(logger, "   ...including {} output with value {}", if local { "to_remote" } else { "to_local" }, value_to_b);
1038                 } else {
1039                         value_to_b = 0;
1040                 }
1041
1042                 let num_nondust_htlcs = included_non_dust_htlcs.len();
1043
1044                 let channel_parameters =
1045                         if local { self.channel_transaction_parameters.as_holder_broadcastable() }
1046                         else { self.channel_transaction_parameters.as_counterparty_broadcastable() };
1047                 let tx = CommitmentTransaction::new_with_auxiliary_htlc_data(commitment_number,
1048                                                                              value_to_a as u64,
1049                                                                              value_to_b as u64,
1050                                                                              keys.clone(),
1051                                                                              feerate_per_kw,
1052                                                                              &mut included_non_dust_htlcs,
1053                                                                              &channel_parameters
1054                 );
1055                 let mut htlcs_included = included_non_dust_htlcs;
1056                 // The unwrap is safe, because all non-dust HTLCs have been assigned an output index
1057                 htlcs_included.sort_unstable_by_key(|h| h.0.transaction_output_index.unwrap());
1058                 htlcs_included.append(&mut included_dust_htlcs);
1059
1060                 (tx, num_nondust_htlcs, htlcs_included)
1061         }
1062
1063         #[inline]
1064         fn get_closing_scriptpubkey(&self) -> Script {
1065                 let channel_close_key_hash = WPubkeyHash::hash(&self.shutdown_pubkey.serialize());
1066                 Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&channel_close_key_hash[..]).into_script()
1067         }
1068
1069         #[inline]
1070         fn get_closing_transaction_weight(&self, a_scriptpubkey: Option<&Script>, b_scriptpubkey: Option<&Script>) -> u64 {
1071                 let mut ret =
1072                 (4 +                                           // version
1073                  1 +                                           // input count
1074                  36 +                                          // prevout
1075                  1 +                                           // script length (0)
1076                  4 +                                           // sequence
1077                  1 +                                           // output count
1078                  4                                             // lock time
1079                  )*4 +                                         // * 4 for non-witness parts
1080                 2 +                                            // witness marker and flag
1081                 1 +                                            // witness element count
1082                 4 +                                            // 4 element lengths (2 sigs, multisig dummy, and witness script)
1083                 self.get_funding_redeemscript().len() as u64 + // funding witness script
1084                 2*(1 + 71);                                    // two signatures + sighash type flags
1085                 if let Some(spk) = a_scriptpubkey {
1086                         ret += ((8+1) +                            // output values and script length
1087                                 spk.len() as u64) * 4;                 // scriptpubkey and witness multiplier
1088                 }
1089                 if let Some(spk) = b_scriptpubkey {
1090                         ret += ((8+1) +                            // output values and script length
1091                                 spk.len() as u64) * 4;                 // scriptpubkey and witness multiplier
1092                 }
1093                 ret
1094         }
1095
1096         #[inline]
1097         fn build_closing_transaction(&self, proposed_total_fee_satoshis: u64, skip_remote_output: bool) -> (Transaction, u64) {
1098                 let txins = {
1099                         let mut ins: Vec<TxIn> = Vec::new();
1100                         ins.push(TxIn {
1101                                 previous_output: self.funding_outpoint().into_bitcoin_outpoint(),
1102                                 script_sig: Script::new(),
1103                                 sequence: 0xffffffff,
1104                                 witness: Vec::new(),
1105                         });
1106                         ins
1107                 };
1108
1109                 assert!(self.pending_inbound_htlcs.is_empty());
1110                 assert!(self.pending_outbound_htlcs.is_empty());
1111                 let mut txouts: Vec<(TxOut, ())> = Vec::new();
1112
1113                 let mut total_fee_satoshis = proposed_total_fee_satoshis;
1114                 let value_to_self: i64 = (self.value_to_self_msat as i64) / 1000 - if self.is_outbound() { total_fee_satoshis as i64 } else { 0 };
1115                 let value_to_remote: 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 };
1116
1117                 if value_to_self < 0 {
1118                         assert!(self.is_outbound());
1119                         total_fee_satoshis += (-value_to_self) as u64;
1120                 } else if value_to_remote < 0 {
1121                         assert!(!self.is_outbound());
1122                         total_fee_satoshis += (-value_to_remote) as u64;
1123                 }
1124
1125                 if !skip_remote_output && value_to_remote as u64 > self.holder_dust_limit_satoshis {
1126                         txouts.push((TxOut {
1127                                 script_pubkey: self.counterparty_shutdown_scriptpubkey.clone().unwrap(),
1128                                 value: value_to_remote as u64
1129                         }, ()));
1130                 }
1131
1132                 if value_to_self as u64 > self.holder_dust_limit_satoshis {
1133                         txouts.push((TxOut {
1134                                 script_pubkey: self.get_closing_scriptpubkey(),
1135                                 value: value_to_self as u64
1136                         }, ()));
1137                 }
1138
1139                 transaction_utils::sort_outputs(&mut txouts, |_, _| { cmp::Ordering::Equal }); // Ordering doesnt matter if they used our pubkey...
1140
1141                 let mut outputs: Vec<TxOut> = Vec::new();
1142                 for out in txouts.drain(..) {
1143                         outputs.push(out.0);
1144                 }
1145
1146                 (Transaction {
1147                         version: 2,
1148                         lock_time: 0,
1149                         input: txins,
1150                         output: outputs,
1151                 }, total_fee_satoshis)
1152         }
1153
1154         fn funding_outpoint(&self) -> OutPoint {
1155                 self.channel_transaction_parameters.funding_outpoint.unwrap()
1156         }
1157
1158         #[inline]
1159         /// Creates a set of keys for build_commitment_transaction to generate a transaction which our
1160         /// counterparty will sign (ie DO NOT send signatures over a transaction created by this to
1161         /// our counterparty!)
1162         /// The result is a transaction which we can revoke broadcastership of (ie a "local" transaction)
1163         /// TODO Some magic rust shit to compile-time check this?
1164         fn build_holder_transaction_keys(&self, commitment_number: u64) -> Result<TxCreationKeys, ChannelError> {
1165                 let per_commitment_point = self.holder_signer.get_per_commitment_point(commitment_number, &self.secp_ctx);
1166                 let delayed_payment_base = &self.get_holder_pubkeys().delayed_payment_basepoint;
1167                 let htlc_basepoint = &self.get_holder_pubkeys().htlc_basepoint;
1168                 let counterparty_pubkeys = self.get_counterparty_pubkeys();
1169
1170                 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()))
1171         }
1172
1173         #[inline]
1174         /// Creates a set of keys for build_commitment_transaction to generate a transaction which we
1175         /// will sign and send to our counterparty.
1176         /// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
1177         fn build_remote_transaction_keys(&self) -> Result<TxCreationKeys, ChannelError> {
1178                 //TODO: Ensure that the payment_key derived here ends up in the library users' wallet as we
1179                 //may see payments to it!
1180                 let revocation_basepoint = &self.get_holder_pubkeys().revocation_basepoint;
1181                 let htlc_basepoint = &self.get_holder_pubkeys().htlc_basepoint;
1182                 let counterparty_pubkeys = self.get_counterparty_pubkeys();
1183
1184                 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()))
1185         }
1186
1187         /// Gets the redeemscript for the funding transaction output (ie the funding transaction output
1188         /// pays to get_funding_redeemscript().to_v0_p2wsh()).
1189         /// Panics if called before accept_channel/new_from_req
1190         pub fn get_funding_redeemscript(&self) -> Script {
1191                 make_funding_redeemscript(&self.get_holder_pubkeys().funding_pubkey, self.counterparty_funding_pubkey())
1192         }
1193
1194         /// Builds the htlc-success or htlc-timeout transaction which spends a given HTLC output
1195         /// @local is used only to convert relevant internal structures which refer to remote vs local
1196         /// to decide value of outputs and direction of HTLCs.
1197         fn build_htlc_transaction(&self, prev_hash: &Txid, htlc: &HTLCOutputInCommitment, local: bool, keys: &TxCreationKeys, feerate_per_kw: u32) -> Transaction {
1198                 chan_utils::build_htlc_transaction(prev_hash, feerate_per_kw, if local { self.get_counterparty_selected_contest_delay() } else { self.get_holder_selected_contest_delay() }, htlc, &keys.broadcaster_delayed_payment_key, &keys.revocation_key)
1199         }
1200
1201         /// Per HTLC, only one get_update_fail_htlc or get_update_fulfill_htlc call may be made.
1202         /// In such cases we debug_assert!(false) and return a ChannelError::Ignore. Thus, will always
1203         /// return Ok(_) if debug assertions are turned on or preconditions are met.
1204         ///
1205         /// Note that it is still possible to hit these assertions in case we find a preimage on-chain
1206         /// but then have a reorg which settles on an HTLC-failure on chain.
1207         fn get_update_fulfill_htlc<L: Deref>(&mut self, htlc_id_arg: u64, payment_preimage_arg: PaymentPreimage, logger: &L) -> Result<(Option<msgs::UpdateFulfillHTLC>, Option<ChannelMonitorUpdate>), ChannelError> where L::Target: Logger {
1208                 // Either ChannelFunded got set (which means it won't be unset) or there is no way any
1209                 // caller thought we could have something claimed (cause we wouldn't have accepted in an
1210                 // incoming HTLC anyway). If we got to ShutdownComplete, callers aren't allowed to call us,
1211                 // either.
1212                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1213                         panic!("Was asked to fulfill an HTLC when channel was not in an operational state");
1214                 }
1215                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
1216
1217                 let payment_hash_calc = PaymentHash(Sha256::hash(&payment_preimage_arg.0[..]).into_inner());
1218
1219                 // ChannelManager may generate duplicate claims/fails due to HTLC update events from
1220                 // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
1221                 // these, but for now we just have to treat them as normal.
1222
1223                 let mut pending_idx = std::usize::MAX;
1224                 for (idx, htlc) in self.pending_inbound_htlcs.iter().enumerate() {
1225                         if htlc.htlc_id == htlc_id_arg {
1226                                 assert_eq!(htlc.payment_hash, payment_hash_calc);
1227                                 match htlc.state {
1228                                         InboundHTLCState::Committed => {},
1229                                         InboundHTLCState::LocalRemoved(ref reason) => {
1230                                                 if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
1231                                                 } else {
1232                                                         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()));
1233                                                 }
1234                                                 debug_assert!(false, "Tried to fulfill an HTLC that was already fail/fulfilled");
1235                                                 return Ok((None, None));
1236                                         },
1237                                         _ => {
1238                                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1239                                                 // Don't return in release mode here so that we can update channel_monitor
1240                                         }
1241                                 }
1242                                 pending_idx = idx;
1243                                 break;
1244                         }
1245                 }
1246                 if pending_idx == std::usize::MAX {
1247                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
1248                 }
1249
1250                 // Now update local state:
1251                 //
1252                 // We have to put the payment_preimage in the channel_monitor right away here to ensure we
1253                 // can claim it even if the channel hits the chain before we see their next commitment.
1254                 self.latest_monitor_update_id += 1;
1255                 let monitor_update = ChannelMonitorUpdate {
1256                         update_id: self.latest_monitor_update_id,
1257                         updates: vec![ChannelMonitorUpdateStep::PaymentPreimage {
1258                                 payment_preimage: payment_preimage_arg.clone(),
1259                         }],
1260                 };
1261
1262                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
1263                         for pending_update in self.holding_cell_htlc_updates.iter() {
1264                                 match pending_update {
1265                                         &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
1266                                                 if htlc_id_arg == htlc_id {
1267                                                         // Make sure we don't leave latest_monitor_update_id incremented here:
1268                                                         self.latest_monitor_update_id -= 1;
1269                                                         debug_assert!(false, "Tried to fulfill an HTLC that was already fulfilled");
1270                                                         return Ok((None, None));
1271                                                 }
1272                                         },
1273                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
1274                                                 if htlc_id_arg == htlc_id {
1275                                                         log_warn!(logger, "Have preimage and want to fulfill HTLC with pending failure against channel {}", log_bytes!(self.channel_id()));
1276                                                         // TODO: We may actually be able to switch to a fulfill here, though its
1277                                                         // rare enough it may not be worth the complexity burden.
1278                                                         debug_assert!(false, "Tried to fulfill an HTLC that was already failed");
1279                                                         return Ok((None, Some(monitor_update)));
1280                                                 }
1281                                         },
1282                                         _ => {}
1283                                 }
1284                         }
1285                         log_trace!(logger, "Adding HTLC claim to holding_cell! Current state: {}", self.channel_state);
1286                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::ClaimHTLC {
1287                                 payment_preimage: payment_preimage_arg, htlc_id: htlc_id_arg,
1288                         });
1289                         return Ok((None, Some(monitor_update)));
1290                 }
1291
1292                 {
1293                         let htlc = &mut self.pending_inbound_htlcs[pending_idx];
1294                         if let InboundHTLCState::Committed = htlc.state {
1295                         } else {
1296                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1297                                 return Ok((None, Some(monitor_update)));
1298                         }
1299                         log_trace!(logger, "Upgrading HTLC {} to LocalRemoved with a Fulfill!", log_bytes!(htlc.payment_hash.0));
1300                         htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::Fulfill(payment_preimage_arg.clone()));
1301                 }
1302
1303                 Ok((Some(msgs::UpdateFulfillHTLC {
1304                         channel_id: self.channel_id(),
1305                         htlc_id: htlc_id_arg,
1306                         payment_preimage: payment_preimage_arg,
1307                 }), Some(monitor_update)))
1308         }
1309
1310         pub fn get_update_fulfill_htlc_and_commit<L: Deref>(&mut self, htlc_id: u64, payment_preimage: PaymentPreimage, logger: &L) -> Result<(Option<(msgs::UpdateFulfillHTLC, msgs::CommitmentSigned)>, Option<ChannelMonitorUpdate>), ChannelError> where L::Target: Logger {
1311                 match self.get_update_fulfill_htlc(htlc_id, payment_preimage, logger)? {
1312                         (Some(update_fulfill_htlc), Some(mut monitor_update)) => {
1313                                 let (commitment, mut additional_update) = self.send_commitment_no_status_check(logger)?;
1314                                 // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
1315                                 // strictly increasing by one, so decrement it here.
1316                                 self.latest_monitor_update_id = monitor_update.update_id;
1317                                 monitor_update.updates.append(&mut additional_update.updates);
1318                                 Ok((Some((update_fulfill_htlc, commitment)), Some(monitor_update)))
1319                         },
1320                         (Some(update_fulfill_htlc), None) => {
1321                                 let (commitment, monitor_update) = self.send_commitment_no_status_check(logger)?;
1322                                 Ok((Some((update_fulfill_htlc, commitment)), Some(monitor_update)))
1323                         },
1324                         (None, Some(monitor_update)) => Ok((None, Some(monitor_update))),
1325                         (None, None) => Ok((None, None))
1326                 }
1327         }
1328
1329         /// Per HTLC, only one get_update_fail_htlc or get_update_fulfill_htlc call may be made.
1330         /// In such cases we debug_assert!(false) and return a ChannelError::Ignore. Thus, will always
1331         /// return Ok(_) if debug assertions are turned on or preconditions are met.
1332         ///
1333         /// Note that it is still possible to hit these assertions in case we find a preimage on-chain
1334         /// but then have a reorg which settles on an HTLC-failure on chain.
1335         pub fn get_update_fail_htlc(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket) -> Result<Option<msgs::UpdateFailHTLC>, ChannelError> {
1336                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1337                         panic!("Was asked to fail an HTLC when channel was not in an operational state");
1338                 }
1339                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
1340
1341                 // ChannelManager may generate duplicate claims/fails due to HTLC update events from
1342                 // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
1343                 // these, but for now we just have to treat them as normal.
1344
1345                 let mut pending_idx = std::usize::MAX;
1346                 for (idx, htlc) in self.pending_inbound_htlcs.iter().enumerate() {
1347                         if htlc.htlc_id == htlc_id_arg {
1348                                 match htlc.state {
1349                                         InboundHTLCState::Committed => {},
1350                                         InboundHTLCState::LocalRemoved(_) => {
1351                                                 debug_assert!(false, "Tried to fail an HTLC that was already fail/fulfilled");
1352                                                 return Ok(None);
1353                                         },
1354                                         _ => {
1355                                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1356                                                 return Err(ChannelError::Ignore(format!("Unable to find a pending HTLC which matched the given HTLC ID ({})", htlc.htlc_id)));
1357                                         }
1358                                 }
1359                                 pending_idx = idx;
1360                         }
1361                 }
1362                 if pending_idx == std::usize::MAX {
1363                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
1364                 }
1365
1366                 // Now update local state:
1367                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
1368                         for pending_update in self.holding_cell_htlc_updates.iter() {
1369                                 match pending_update {
1370                                         &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
1371                                                 if htlc_id_arg == htlc_id {
1372                                                         debug_assert!(false, "Tried to fail an HTLC that was already fulfilled");
1373                                                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
1374                                                 }
1375                                         },
1376                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
1377                                                 if htlc_id_arg == htlc_id {
1378                                                         debug_assert!(false, "Tried to fail an HTLC that was already failed");
1379                                                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
1380                                                 }
1381                                         },
1382                                         _ => {}
1383                                 }
1384                         }
1385                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::FailHTLC {
1386                                 htlc_id: htlc_id_arg,
1387                                 err_packet,
1388                         });
1389                         return Ok(None);
1390                 }
1391
1392                 {
1393                         let htlc = &mut self.pending_inbound_htlcs[pending_idx];
1394                         htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(err_packet.clone()));
1395                 }
1396
1397                 Ok(Some(msgs::UpdateFailHTLC {
1398                         channel_id: self.channel_id(),
1399                         htlc_id: htlc_id_arg,
1400                         reason: err_packet
1401                 }))
1402         }
1403
1404         // Message handlers:
1405
1406         pub fn accept_channel(&mut self, msg: &msgs::AcceptChannel, config: &UserConfig, their_features: InitFeatures) -> Result<(), ChannelError> {
1407                 // Check sanity of message fields:
1408                 if !self.is_outbound() {
1409                         return Err(ChannelError::Close("Got an accept_channel message from an inbound peer".to_owned()));
1410                 }
1411                 if self.channel_state != ChannelState::OurInitSent as u32 {
1412                         return Err(ChannelError::Close("Got an accept_channel message at a strange time".to_owned()));
1413                 }
1414                 if msg.dust_limit_satoshis > 21000000 * 100000000 {
1415                         return Err(ChannelError::Close(format!("Peer never wants payout outputs? dust_limit_satoshis was {}", msg.dust_limit_satoshis)));
1416                 }
1417                 if msg.channel_reserve_satoshis > self.channel_value_satoshis {
1418                         return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must not be greater than ({})", msg.channel_reserve_satoshis, self.channel_value_satoshis)));
1419                 }
1420                 if msg.dust_limit_satoshis > msg.channel_reserve_satoshis {
1421                         return Err(ChannelError::Close(format!("Bogus channel_reserve ({}) and dust_limit ({})", msg.channel_reserve_satoshis, msg.dust_limit_satoshis)));
1422                 }
1423                 if msg.channel_reserve_satoshis < self.holder_dust_limit_satoshis {
1424                         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)));
1425                 }
1426                 let remote_reserve = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis);
1427                 if msg.dust_limit_satoshis > remote_reserve {
1428                         return Err(ChannelError::Close(format!("Dust limit ({}) is bigger than our channel reserve ({})", msg.dust_limit_satoshis, remote_reserve)));
1429                 }
1430                 let full_channel_value_msat = (self.channel_value_satoshis - msg.channel_reserve_satoshis) * 1000;
1431                 if msg.htlc_minimum_msat >= full_channel_value_msat {
1432                         return Err(ChannelError::Close(format!("Minimum htlc value ({}) is full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat)));
1433                 }
1434                 let max_delay_acceptable = u16::min(config.peer_channel_config_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
1435                 if msg.to_self_delay > max_delay_acceptable {
1436                         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)));
1437                 }
1438                 if msg.max_accepted_htlcs < 1 {
1439                         return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel".to_owned()));
1440                 }
1441                 if msg.max_accepted_htlcs > MAX_HTLCS {
1442                         return Err(ChannelError::Close(format!("max_accepted_htlcs was {}. It must not be larger than {}", msg.max_accepted_htlcs, MAX_HTLCS)));
1443                 }
1444
1445                 // Now check against optional parameters as set by config...
1446                 if msg.htlc_minimum_msat > config.peer_channel_config_limits.max_htlc_minimum_msat {
1447                         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)));
1448                 }
1449                 if msg.max_htlc_value_in_flight_msat < config.peer_channel_config_limits.min_max_htlc_value_in_flight_msat {
1450                         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)));
1451                 }
1452                 if msg.channel_reserve_satoshis > config.peer_channel_config_limits.max_channel_reserve_satoshis {
1453                         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)));
1454                 }
1455                 if msg.max_accepted_htlcs < config.peer_channel_config_limits.min_max_accepted_htlcs {
1456                         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)));
1457                 }
1458                 if msg.dust_limit_satoshis < MIN_DUST_LIMIT_SATOSHIS {
1459                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the implementation limit ({})", msg.dust_limit_satoshis, MIN_DUST_LIMIT_SATOSHIS)));
1460                 }
1461                 if msg.dust_limit_satoshis > MAX_DUST_LIMIT_SATOSHIS {
1462                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the implementation limit ({})", msg.dust_limit_satoshis, MAX_DUST_LIMIT_SATOSHIS)));
1463                 }
1464                 if msg.minimum_depth > config.peer_channel_config_limits.max_minimum_depth {
1465                         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)));
1466                 }
1467
1468                 let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() {
1469                         match &msg.shutdown_scriptpubkey {
1470                                 &OptionalField::Present(ref script) => {
1471                                         // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything
1472                                         if script.len() == 0 {
1473                                                 None
1474                                         // Peer is signaling upfront_shutdown and has provided a non-accepted scriptpubkey format. Fail the channel
1475                                         } else if is_unsupported_shutdown_script(&their_features, script) {
1476                                                 return Err(ChannelError::Close(format!("Peer is signaling upfront_shutdown but has provided a non-accepted scriptpubkey format. script: ({})", script.to_bytes().to_hex())));
1477                                         } else {
1478                                                 Some(script.clone())
1479                                         }
1480                                 },
1481                                 // 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
1482                                 &OptionalField::Absent => {
1483                                         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()));
1484                                 }
1485                         }
1486                 } else { None };
1487
1488                 self.counterparty_dust_limit_satoshis = msg.dust_limit_satoshis;
1489                 self.counterparty_max_htlc_value_in_flight_msat = cmp::min(msg.max_htlc_value_in_flight_msat, self.channel_value_satoshis * 1000);
1490                 self.counterparty_selected_channel_reserve_satoshis = msg.channel_reserve_satoshis;
1491                 self.counterparty_htlc_minimum_msat = msg.htlc_minimum_msat;
1492                 self.counterparty_max_accepted_htlcs = msg.max_accepted_htlcs;
1493                 self.minimum_depth = msg.minimum_depth;
1494
1495                 let counterparty_pubkeys = ChannelPublicKeys {
1496                         funding_pubkey: msg.funding_pubkey,
1497                         revocation_basepoint: msg.revocation_basepoint,
1498                         payment_point: msg.payment_point,
1499                         delayed_payment_basepoint: msg.delayed_payment_basepoint,
1500                         htlc_basepoint: msg.htlc_basepoint
1501                 };
1502
1503                 self.channel_transaction_parameters.counterparty_parameters = Some(CounterpartyChannelTransactionParameters {
1504                         selected_contest_delay: msg.to_self_delay,
1505                         pubkeys: counterparty_pubkeys,
1506                 });
1507
1508                 self.counterparty_cur_commitment_point = Some(msg.first_per_commitment_point);
1509                 self.counterparty_shutdown_scriptpubkey = counterparty_shutdown_scriptpubkey;
1510
1511                 self.channel_state = ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32;
1512
1513                 Ok(())
1514         }
1515
1516         fn funding_created_signature<L: Deref>(&mut self, sig: &Signature, logger: &L) -> Result<(Txid, CommitmentTransaction, Signature), ChannelError> where L::Target: Logger {
1517                 let funding_script = self.get_funding_redeemscript();
1518
1519                 let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number)?;
1520                 let initial_commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, false, self.feerate_per_kw, logger).0;
1521                 {
1522                         let trusted_tx = initial_commitment_tx.trust();
1523                         let initial_commitment_bitcoin_tx = trusted_tx.built_transaction();
1524                         let sighash = initial_commitment_bitcoin_tx.get_sighash_all(&funding_script, self.channel_value_satoshis);
1525                         // They sign the holder commitment transaction...
1526                         log_trace!(logger, "Checking funding_created tx signature {} by key {} against tx {} (sighash {}) with redeemscript {}", log_bytes!(sig.serialize_compact()[..]), log_bytes!(self.counterparty_funding_pubkey().serialize()), encode::serialize_hex(&initial_commitment_bitcoin_tx.transaction), log_bytes!(sighash[..]), encode::serialize_hex(&funding_script));
1527                         secp_check!(self.secp_ctx.verify(&sighash, &sig, self.counterparty_funding_pubkey()), "Invalid funding_created signature from peer".to_owned());
1528                 }
1529
1530                 let counterparty_keys = self.build_remote_transaction_keys()?;
1531                 let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, self.feerate_per_kw, logger).0;
1532
1533                 let counterparty_trusted_tx = counterparty_initial_commitment_tx.trust();
1534                 let counterparty_initial_bitcoin_tx = counterparty_trusted_tx.built_transaction();
1535                 log_trace!(logger, "Initial counterparty ID {} tx {}", counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
1536
1537                 let counterparty_signature = self.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, &self.secp_ctx)
1538                                 .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0;
1539
1540                 // We sign "counterparty" commitment transaction, allowing them to broadcast the tx if they wish.
1541                 Ok((counterparty_initial_bitcoin_tx.txid, initial_commitment_tx, counterparty_signature))
1542         }
1543
1544         fn counterparty_funding_pubkey(&self) -> &PublicKey {
1545                 &self.get_counterparty_pubkeys().funding_pubkey
1546         }
1547
1548         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 {
1549                 if self.is_outbound() {
1550                         return Err(ChannelError::Close("Received funding_created for an outbound channel?".to_owned()));
1551                 }
1552                 if self.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
1553                         // BOLT 2 says that if we disconnect before we send funding_signed we SHOULD NOT
1554                         // remember the channel, so it's safe to just send an error_message here and drop the
1555                         // channel.
1556                         return Err(ChannelError::Close("Received funding_created after we got the channel!".to_owned()));
1557                 }
1558                 if self.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
1559                                 self.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
1560                                 self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
1561                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
1562                 }
1563
1564                 let funding_txo = OutPoint { txid: msg.funding_txid, index: msg.funding_output_index };
1565                 self.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
1566                 // This is an externally observable change before we finish all our checks.  In particular
1567                 // funding_created_signature may fail.
1568                 self.holder_signer.ready_channel(&self.channel_transaction_parameters);
1569
1570                 let (counterparty_initial_commitment_txid, initial_commitment_tx, signature) = match self.funding_created_signature(&msg.signature, logger) {
1571                         Ok(res) => res,
1572                         Err(ChannelError::Close(e)) => {
1573                                 self.channel_transaction_parameters.funding_outpoint = None;
1574                                 return Err(ChannelError::Close(e));
1575                         },
1576                         Err(e) => {
1577                                 // The only error we know how to handle is ChannelError::Close, so we fall over here
1578                                 // to make sure we don't continue with an inconsistent state.
1579                                 panic!("unexpected error type from funding_created_signature {:?}", e);
1580                         }
1581                 };
1582
1583                 let holder_commitment_tx = HolderCommitmentTransaction::new(
1584                         initial_commitment_tx,
1585                         msg.signature,
1586                         Vec::new(),
1587                         &self.get_holder_pubkeys().funding_pubkey,
1588                         self.counterparty_funding_pubkey()
1589                 );
1590
1591                 // Now that we're past error-generating stuff, update our local state:
1592
1593                 let funding_redeemscript = self.get_funding_redeemscript();
1594                 let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
1595                 let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound());
1596                 let channel_monitor = ChannelMonitor::new(self.secp_ctx.clone(), self.holder_signer.clone(),
1597                                                           &self.shutdown_pubkey, self.get_holder_selected_contest_delay(),
1598                                                           &self.destination_script, (funding_txo, funding_txo_script.clone()),
1599                                                           &self.channel_transaction_parameters,
1600                                                           funding_redeemscript.clone(), self.channel_value_satoshis,
1601                                                           obscure_factor,
1602                                                           holder_commitment_tx, best_block);
1603
1604                 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);
1605
1606                 self.channel_state = ChannelState::FundingSent as u32;
1607                 self.channel_id = funding_txo.to_channel_id();
1608                 self.cur_counterparty_commitment_transaction_number -= 1;
1609                 self.cur_holder_commitment_transaction_number -= 1;
1610
1611                 Ok((msgs::FundingSigned {
1612                         channel_id: self.channel_id,
1613                         signature
1614                 }, channel_monitor))
1615         }
1616
1617         /// Handles a funding_signed message from the remote end.
1618         /// If this call is successful, broadcast the funding transaction (and not before!)
1619         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 {
1620                 if !self.is_outbound() {
1621                         return Err(ChannelError::Close("Received funding_signed for an inbound channel?".to_owned()));
1622                 }
1623                 if self.channel_state & !(ChannelState::MonitorUpdateFailed as u32) != ChannelState::FundingCreated as u32 {
1624                         return Err(ChannelError::Close("Received funding_signed in strange state!".to_owned()));
1625                 }
1626                 if self.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
1627                                 self.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
1628                                 self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
1629                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
1630                 }
1631
1632                 let funding_script = self.get_funding_redeemscript();
1633
1634                 let counterparty_keys = self.build_remote_transaction_keys()?;
1635                 let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, self.feerate_per_kw, logger).0;
1636                 let counterparty_trusted_tx = counterparty_initial_commitment_tx.trust();
1637                 let counterparty_initial_bitcoin_tx = counterparty_trusted_tx.built_transaction();
1638
1639                 log_trace!(logger, "Initial counterparty ID {} tx {}", counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
1640
1641                 let holder_signer = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number)?;
1642                 let initial_commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &holder_signer, true, false, self.feerate_per_kw, logger).0;
1643                 {
1644                         let trusted_tx = initial_commitment_tx.trust();
1645                         let initial_commitment_bitcoin_tx = trusted_tx.built_transaction();
1646                         let sighash = initial_commitment_bitcoin_tx.get_sighash_all(&funding_script, self.channel_value_satoshis);
1647                         // They sign our commitment transaction, allowing us to broadcast the tx if we wish.
1648                         if let Err(_) = self.secp_ctx.verify(&sighash, &msg.signature, &self.get_counterparty_pubkeys().funding_pubkey) {
1649                                 return Err(ChannelError::Close("Invalid funding_signed signature from peer".to_owned()));
1650                         }
1651                 }
1652
1653                 let holder_commitment_tx = HolderCommitmentTransaction::new(
1654                         initial_commitment_tx,
1655                         msg.signature,
1656                         Vec::new(),
1657                         &self.get_holder_pubkeys().funding_pubkey,
1658                         self.counterparty_funding_pubkey()
1659                 );
1660
1661
1662                 let funding_redeemscript = self.get_funding_redeemscript();
1663                 let funding_txo = self.get_funding_txo().unwrap();
1664                 let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
1665                 let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound());
1666                 let channel_monitor = ChannelMonitor::new(self.secp_ctx.clone(), self.holder_signer.clone(),
1667                                                           &self.shutdown_pubkey, self.get_holder_selected_contest_delay(),
1668                                                           &self.destination_script, (funding_txo, funding_txo_script),
1669                                                           &self.channel_transaction_parameters,
1670                                                           funding_redeemscript.clone(), self.channel_value_satoshis,
1671                                                           obscure_factor,
1672                                                           holder_commitment_tx, best_block);
1673
1674                 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);
1675
1676                 assert_eq!(self.channel_state & (ChannelState::MonitorUpdateFailed as u32), 0); // We have no had any monitor(s) yet to fail update!
1677                 self.channel_state = ChannelState::FundingSent as u32;
1678                 self.cur_holder_commitment_transaction_number -= 1;
1679                 self.cur_counterparty_commitment_transaction_number -= 1;
1680
1681                 Ok((channel_monitor, self.funding_transaction.as_ref().cloned().unwrap()))
1682         }
1683
1684         pub fn funding_locked(&mut self, msg: &msgs::FundingLocked) -> Result<(), ChannelError> {
1685                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
1686                         return Err(ChannelError::Close("Peer sent funding_locked when we needed a channel_reestablish".to_owned()));
1687                 }
1688
1689                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
1690
1691                 if non_shutdown_state == ChannelState::FundingSent as u32 {
1692                         self.channel_state |= ChannelState::TheirFundingLocked as u32;
1693                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) {
1694                         self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
1695                         self.update_time_counter += 1;
1696                 } else if (self.channel_state & (ChannelState::ChannelFunded as u32) != 0 &&
1697                                  // Note that funding_signed/funding_created will have decremented both by 1!
1698                                  self.cur_holder_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1 &&
1699                                  self.cur_counterparty_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1) ||
1700                                 // If we reconnected before sending our funding locked they may still resend theirs:
1701                                 (self.channel_state & (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32) ==
1702                                                       (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32)) {
1703                         if self.counterparty_cur_commitment_point != Some(msg.next_per_commitment_point) {
1704                                 return Err(ChannelError::Close("Peer sent a reconnect funding_locked with a different point".to_owned()));
1705                         }
1706                         // They probably disconnected/reconnected and re-sent the funding_locked, which is required
1707                         return Ok(());
1708                 } else {
1709                         return Err(ChannelError::Close("Peer sent a funding_locked at a strange time".to_owned()));
1710                 }
1711
1712                 self.counterparty_prev_commitment_point = self.counterparty_cur_commitment_point;
1713                 self.counterparty_cur_commitment_point = Some(msg.next_per_commitment_point);
1714                 Ok(())
1715         }
1716
1717         /// Returns (inbound_htlc_count, htlc_inbound_value_msat)
1718         fn get_inbound_pending_htlc_stats(&self) -> (u32, u64) {
1719                 let mut htlc_inbound_value_msat = 0;
1720                 for ref htlc in self.pending_inbound_htlcs.iter() {
1721                         htlc_inbound_value_msat += htlc.amount_msat;
1722                 }
1723                 (self.pending_inbound_htlcs.len() as u32, htlc_inbound_value_msat)
1724         }
1725
1726         /// Returns (outbound_htlc_count, htlc_outbound_value_msat) *including* pending adds in our
1727         /// holding cell.
1728         fn get_outbound_pending_htlc_stats(&self) -> (u32, u64) {
1729                 let mut htlc_outbound_value_msat = 0;
1730                 for ref htlc in self.pending_outbound_htlcs.iter() {
1731                         htlc_outbound_value_msat += htlc.amount_msat;
1732                 }
1733
1734                 let mut htlc_outbound_count = self.pending_outbound_htlcs.len();
1735                 for update in self.holding_cell_htlc_updates.iter() {
1736                         if let &HTLCUpdateAwaitingACK::AddHTLC { ref amount_msat, .. } = update {
1737                                 htlc_outbound_count += 1;
1738                                 htlc_outbound_value_msat += amount_msat;
1739                         }
1740                 }
1741
1742                 (htlc_outbound_count as u32, htlc_outbound_value_msat)
1743         }
1744
1745         /// Get the available (ie not including pending HTLCs) inbound and outbound balance in msat.
1746         /// Doesn't bother handling the
1747         /// if-we-removed-it-already-but-haven't-fully-resolved-they-can-still-send-an-inbound-HTLC
1748         /// corner case properly.
1749         pub fn get_inbound_outbound_available_balance_msat(&self) -> (u64, u64) {
1750                 // Note that we have to handle overflow due to the above case.
1751                 (cmp::max(self.channel_value_satoshis as i64 * 1000 - self.value_to_self_msat as i64 - self.get_inbound_pending_htlc_stats().1 as i64, 0) as u64,
1752                 cmp::max(self.value_to_self_msat as i64 - self.get_outbound_pending_htlc_stats().1 as i64, 0) as u64)
1753         }
1754
1755         // Get the fee cost of a commitment tx with a given number of HTLC outputs.
1756         // Note that num_htlcs should not include dust HTLCs.
1757         fn commit_tx_fee_msat(&self, num_htlcs: usize) -> u64 {
1758                 // Note that we need to divide before multiplying to round properly,
1759                 // since the lowest denomination of bitcoin on-chain is the satoshi.
1760                 (COMMITMENT_TX_BASE_WEIGHT + num_htlcs as u64 * COMMITMENT_TX_WEIGHT_PER_HTLC) * self.feerate_per_kw as u64 / 1000 * 1000
1761         }
1762
1763         // Get the commitment tx fee for the local's (i.e. our) next commitment transaction based on the
1764         // number of pending HTLCs that are on track to be in our next commitment tx, plus an additional
1765         // HTLC if `fee_spike_buffer_htlc` is Some, plus a new HTLC given by `new_htlc_amount`. Dust HTLCs
1766         // are excluded.
1767         fn next_local_commit_tx_fee_msat(&self, htlc: HTLCCandidate, fee_spike_buffer_htlc: Option<()>) -> u64 {
1768                 assert!(self.is_outbound());
1769
1770                 let real_dust_limit_success_sat = (self.feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
1771                 let real_dust_limit_timeout_sat = (self.feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
1772
1773                 let mut addl_htlcs = 0;
1774                 if fee_spike_buffer_htlc.is_some() { addl_htlcs += 1; }
1775                 match htlc.origin {
1776                         HTLCInitiator::LocalOffered => {
1777                                 if htlc.amount_msat / 1000 >= real_dust_limit_timeout_sat {
1778                                         addl_htlcs += 1;
1779                                 }
1780                         },
1781                         HTLCInitiator::RemoteOffered => {
1782                                 if htlc.amount_msat / 1000 >= real_dust_limit_success_sat {
1783                                         addl_htlcs += 1;
1784                                 }
1785                         }
1786                 }
1787
1788                 let mut included_htlcs = 0;
1789                 for ref htlc in self.pending_inbound_htlcs.iter() {
1790                         if htlc.amount_msat / 1000 < real_dust_limit_success_sat {
1791                                 continue
1792                         }
1793                         // We include LocalRemoved HTLCs here because we may still need to broadcast a commitment
1794                         // transaction including this HTLC if it times out before they RAA.
1795                         included_htlcs += 1;
1796                 }
1797
1798                 for ref htlc in self.pending_outbound_htlcs.iter() {
1799                         if htlc.amount_msat / 1000 < real_dust_limit_timeout_sat {
1800                                 continue
1801                         }
1802                         match htlc.state {
1803                                 OutboundHTLCState::LocalAnnounced {..} => included_htlcs += 1,
1804                                 OutboundHTLCState::Committed => included_htlcs += 1,
1805                                 OutboundHTLCState::RemoteRemoved {..} => included_htlcs += 1,
1806                                 // We don't include AwaitingRemoteRevokeToRemove HTLCs because our next commitment
1807                                 // transaction won't be generated until they send us their next RAA, which will mean
1808                                 // dropping any HTLCs in this state.
1809                                 _ => {},
1810                         }
1811                 }
1812
1813                 for htlc in self.holding_cell_htlc_updates.iter() {
1814                         match htlc {
1815                                 &HTLCUpdateAwaitingACK::AddHTLC { amount_msat, .. } => {
1816                                         if amount_msat / 1000 < real_dust_limit_timeout_sat {
1817                                                 continue
1818                                         }
1819                                         included_htlcs += 1
1820                                 },
1821                                 _ => {}, // Don't include claims/fails that are awaiting ack, because once we get the
1822                                          // ack we're guaranteed to never include them in commitment txs anymore.
1823                         }
1824                 }
1825
1826                 let num_htlcs = included_htlcs + addl_htlcs;
1827                 let res = self.commit_tx_fee_msat(num_htlcs);
1828                 #[cfg(any(test, feature = "fuzztarget"))]
1829                 {
1830                         let mut fee = res;
1831                         if fee_spike_buffer_htlc.is_some() {
1832                                 fee = self.commit_tx_fee_msat(num_htlcs - 1);
1833                         }
1834                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len()
1835                                 + self.holding_cell_htlc_updates.len();
1836                         let commitment_tx_info = CommitmentTxInfoCached {
1837                                 fee,
1838                                 total_pending_htlcs,
1839                                 next_holder_htlc_id: match htlc.origin {
1840                                         HTLCInitiator::LocalOffered => self.next_holder_htlc_id + 1,
1841                                         HTLCInitiator::RemoteOffered => self.next_holder_htlc_id,
1842                                 },
1843                                 next_counterparty_htlc_id: match htlc.origin {
1844                                         HTLCInitiator::LocalOffered => self.next_counterparty_htlc_id,
1845                                         HTLCInitiator::RemoteOffered => self.next_counterparty_htlc_id + 1,
1846                                 },
1847                                 feerate: self.feerate_per_kw,
1848                         };
1849                         *self.next_local_commitment_tx_fee_info_cached.lock().unwrap() = Some(commitment_tx_info);
1850                 }
1851                 res
1852         }
1853
1854         // Get the commitment tx fee for the remote's next commitment transaction based on the number of
1855         // pending HTLCs that are on track to be in their next commitment tx, plus an additional HTLC if
1856         // `fee_spike_buffer_htlc` is Some, plus a new HTLC given by `new_htlc_amount`. Dust HTLCs are
1857         // excluded.
1858         fn next_remote_commit_tx_fee_msat(&self, htlc: HTLCCandidate, fee_spike_buffer_htlc: Option<()>) -> u64 {
1859                 assert!(!self.is_outbound());
1860
1861                 let real_dust_limit_success_sat = (self.feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
1862                 let real_dust_limit_timeout_sat = (self.feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
1863
1864                 let mut addl_htlcs = 0;
1865                 if fee_spike_buffer_htlc.is_some() { addl_htlcs += 1; }
1866                 match htlc.origin {
1867                         HTLCInitiator::LocalOffered => {
1868                                 if htlc.amount_msat / 1000 >= real_dust_limit_success_sat {
1869                                         addl_htlcs += 1;
1870                                 }
1871                         },
1872                         HTLCInitiator::RemoteOffered => {
1873                                 if htlc.amount_msat / 1000 >= real_dust_limit_timeout_sat {
1874                                         addl_htlcs += 1;
1875                                 }
1876                         }
1877                 }
1878
1879                 // When calculating the set of HTLCs which will be included in their next commitment_signed, all
1880                 // non-dust inbound HTLCs are included (as all states imply it will be included) and only
1881                 // committed outbound HTLCs, see below.
1882                 let mut included_htlcs = 0;
1883                 for ref htlc in self.pending_inbound_htlcs.iter() {
1884                         if htlc.amount_msat / 1000 <= real_dust_limit_timeout_sat {
1885                                 continue
1886                         }
1887                         included_htlcs += 1;
1888                 }
1889
1890                 for ref htlc in self.pending_outbound_htlcs.iter() {
1891                         if htlc.amount_msat / 1000 <= real_dust_limit_success_sat {
1892                                 continue
1893                         }
1894                         // We only include outbound HTLCs if it will not be included in their next commitment_signed,
1895                         // i.e. if they've responded to us with an RAA after announcement.
1896                         match htlc.state {
1897                                 OutboundHTLCState::Committed => included_htlcs += 1,
1898                                 OutboundHTLCState::RemoteRemoved {..} => included_htlcs += 1,
1899                                 OutboundHTLCState::LocalAnnounced { .. } => included_htlcs += 1,
1900                                 _ => {},
1901                         }
1902                 }
1903
1904                 let num_htlcs = included_htlcs + addl_htlcs;
1905                 let res = self.commit_tx_fee_msat(num_htlcs);
1906                 #[cfg(any(test, feature = "fuzztarget"))]
1907                 {
1908                         let mut fee = res;
1909                         if fee_spike_buffer_htlc.is_some() {
1910                                 fee = self.commit_tx_fee_msat(num_htlcs - 1);
1911                         }
1912                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len();
1913                         let commitment_tx_info = CommitmentTxInfoCached {
1914                                 fee,
1915                                 total_pending_htlcs,
1916                                 next_holder_htlc_id: match htlc.origin {
1917                                         HTLCInitiator::LocalOffered => self.next_holder_htlc_id + 1,
1918                                         HTLCInitiator::RemoteOffered => self.next_holder_htlc_id,
1919                                 },
1920                                 next_counterparty_htlc_id: match htlc.origin {
1921                                         HTLCInitiator::LocalOffered => self.next_counterparty_htlc_id,
1922                                         HTLCInitiator::RemoteOffered => self.next_counterparty_htlc_id + 1,
1923                                 },
1924                                 feerate: self.feerate_per_kw,
1925                         };
1926                         *self.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = Some(commitment_tx_info);
1927                 }
1928                 res
1929         }
1930
1931         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>
1932         where F: for<'a> Fn(&'a Self, PendingHTLCStatus, u16) -> PendingHTLCStatus, L::Target: Logger {
1933                 // We can't accept HTLCs sent after we've sent a shutdown.
1934                 let local_sent_shutdown = (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::LocalShutdownSent as u32)) != (ChannelState::ChannelFunded as u32);
1935                 if local_sent_shutdown {
1936                         pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|20);
1937                 }
1938                 // If the remote has sent a shutdown prior to adding this HTLC, then they are in violation of the spec.
1939                 let remote_sent_shutdown = (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::RemoteShutdownSent as u32)) != (ChannelState::ChannelFunded as u32);
1940                 if remote_sent_shutdown {
1941                         return Err(ChannelError::Close("Got add HTLC message when channel was not in an operational state".to_owned()));
1942                 }
1943                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
1944                         return Err(ChannelError::Close("Peer sent update_add_htlc when we needed a channel_reestablish".to_owned()));
1945                 }
1946                 if msg.amount_msat > self.channel_value_satoshis * 1000 {
1947                         return Err(ChannelError::Close("Remote side tried to send more than the total value of the channel".to_owned()));
1948                 }
1949                 if msg.amount_msat == 0 {
1950                         return Err(ChannelError::Close("Remote side tried to send a 0-msat HTLC".to_owned()));
1951                 }
1952                 if msg.amount_msat < self.holder_htlc_minimum_msat {
1953                         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)));
1954                 }
1955
1956                 let (inbound_htlc_count, htlc_inbound_value_msat) = self.get_inbound_pending_htlc_stats();
1957                 if inbound_htlc_count + 1 > OUR_MAX_HTLCS as u32 {
1958                         return Err(ChannelError::Close(format!("Remote tried to push more than our max accepted HTLCs ({})", OUR_MAX_HTLCS)));
1959                 }
1960                 let holder_max_htlc_value_in_flight_msat = Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis);
1961                 if htlc_inbound_value_msat + msg.amount_msat > holder_max_htlc_value_in_flight_msat {
1962                         return Err(ChannelError::Close(format!("Remote HTLC add would put them over our max HTLC value ({})", holder_max_htlc_value_in_flight_msat)));
1963                 }
1964                 // Check holder_selected_channel_reserve_satoshis (we're getting paid, so they have to at least meet
1965                 // the reserve_satoshis we told them to always have as direct payment so that they lose
1966                 // something if we punish them for broadcasting an old state).
1967                 // Note that we don't really care about having a small/no to_remote output in our local
1968                 // commitment transactions, as the purpose of the channel reserve is to ensure we can
1969                 // punish *them* if they misbehave, so we discount any outbound HTLCs which will not be
1970                 // present in the next commitment transaction we send them (at least for fulfilled ones,
1971                 // failed ones won't modify value_to_self).
1972                 // Note that we will send HTLCs which another instance of rust-lightning would think
1973                 // violate the reserve value if we do not do this (as we forget inbound HTLCs from the
1974                 // Channel state once they will not be present in the next received commitment
1975                 // transaction).
1976                 let mut removed_outbound_total_msat = 0;
1977                 for ref htlc in self.pending_outbound_htlcs.iter() {
1978                         if let OutboundHTLCState::AwaitingRemoteRevokeToRemove(None) = htlc.state {
1979                                 removed_outbound_total_msat += htlc.amount_msat;
1980                         } else if let OutboundHTLCState::AwaitingRemovedRemoteRevoke(None) = htlc.state {
1981                                 removed_outbound_total_msat += htlc.amount_msat;
1982                         }
1983                 }
1984
1985                 let pending_value_to_self_msat =
1986                         self.value_to_self_msat + htlc_inbound_value_msat - removed_outbound_total_msat;
1987                 let pending_remote_value_msat =
1988                         self.channel_value_satoshis * 1000 - pending_value_to_self_msat;
1989                 if pending_remote_value_msat < msg.amount_msat {
1990                         return Err(ChannelError::Close("Remote HTLC add would overdraw remaining funds".to_owned()));
1991                 }
1992
1993                 // Check that the remote can afford to pay for this HTLC on-chain at the current
1994                 // feerate_per_kw, while maintaining their channel reserve (as required by the spec).
1995                 let remote_commit_tx_fee_msat = if self.is_outbound() { 0 } else {
1996                         let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
1997                         self.next_remote_commit_tx_fee_msat(htlc_candidate, None) // Don't include the extra fee spike buffer HTLC in calculations
1998                 };
1999                 if pending_remote_value_msat - msg.amount_msat < remote_commit_tx_fee_msat {
2000                         return Err(ChannelError::Close("Remote HTLC add would not leave enough to pay for fees".to_owned()));
2001                 };
2002
2003                 let chan_reserve_msat =
2004                         Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis) * 1000;
2005                 if pending_remote_value_msat - msg.amount_msat - remote_commit_tx_fee_msat < chan_reserve_msat {
2006                         return Err(ChannelError::Close("Remote HTLC add would put them under remote reserve value".to_owned()));
2007                 }
2008
2009                 if !self.is_outbound() {
2010                         // `2 *` and `Some(())` is for the fee spike buffer we keep for the remote. This deviates from
2011                         // the spec because in the spec, the fee spike buffer requirement doesn't exist on the
2012                         // receiver's side, only on the sender's.
2013                         // Note that when we eventually remove support for fee updates and switch to anchor output
2014                         // fees, we will drop the `2 *`, since we no longer be as sensitive to fee spikes. But, keep
2015                         // the extra htlc when calculating the next remote commitment transaction fee as we should
2016                         // still be able to afford adding this HTLC plus one more future HTLC, regardless of being
2017                         // sensitive to fee spikes.
2018                         let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
2019                         let remote_fee_cost_incl_stuck_buffer_msat = 2 * self.next_remote_commit_tx_fee_msat(htlc_candidate, Some(()));
2020                         if pending_remote_value_msat - msg.amount_msat - chan_reserve_msat < remote_fee_cost_incl_stuck_buffer_msat {
2021                                 // Note that if the pending_forward_status is not updated here, then it's because we're already failing
2022                                 // the HTLC, i.e. its status is already set to failing.
2023                                 log_info!(logger, "Attempting to fail HTLC due to fee spike buffer violation");
2024                                 pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|7);
2025                         }
2026                 } else {
2027                         // Check that they won't violate our local required channel reserve by adding this HTLC.
2028                         let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
2029                         let local_commit_tx_fee_msat = self.next_local_commit_tx_fee_msat(htlc_candidate, None);
2030                         if self.value_to_self_msat < self.counterparty_selected_channel_reserve_satoshis * 1000 + local_commit_tx_fee_msat {
2031                                 return Err(ChannelError::Close("Cannot accept HTLC that would put our balance under counterparty-announced channel reserve value".to_owned()));
2032                         }
2033                 }
2034                 if self.next_counterparty_htlc_id != msg.htlc_id {
2035                         return Err(ChannelError::Close(format!("Remote skipped HTLC ID (skipped ID: {})", self.next_counterparty_htlc_id)));
2036                 }
2037                 if msg.cltv_expiry >= 500000000 {
2038                         return Err(ChannelError::Close("Remote provided CLTV expiry in seconds instead of block height".to_owned()));
2039                 }
2040
2041                 if self.channel_state & ChannelState::LocalShutdownSent as u32 != 0 {
2042                         if let PendingHTLCStatus::Forward(_) = pending_forward_status {
2043                                 panic!("ChannelManager shouldn't be trying to add a forwardable HTLC after we've started closing");
2044                         }
2045                 }
2046
2047                 // Now update local state:
2048                 self.next_counterparty_htlc_id += 1;
2049                 self.pending_inbound_htlcs.push(InboundHTLCOutput {
2050                         htlc_id: msg.htlc_id,
2051                         amount_msat: msg.amount_msat,
2052                         payment_hash: msg.payment_hash,
2053                         cltv_expiry: msg.cltv_expiry,
2054                         state: InboundHTLCState::RemoteAnnounced(pending_forward_status),
2055                 });
2056                 Ok(())
2057         }
2058
2059         /// Marks an outbound HTLC which we have received update_fail/fulfill/malformed
2060         #[inline]
2061         fn mark_outbound_htlc_removed(&mut self, htlc_id: u64, check_preimage: Option<PaymentHash>, fail_reason: Option<HTLCFailReason>) -> Result<&HTLCSource, ChannelError> {
2062                 for htlc in self.pending_outbound_htlcs.iter_mut() {
2063                         if htlc.htlc_id == htlc_id {
2064                                 match check_preimage {
2065                                         None => {},
2066                                         Some(payment_hash) =>
2067                                                 if payment_hash != htlc.payment_hash {
2068                                                         return Err(ChannelError::Close(format!("Remote tried to fulfill HTLC ({}) with an incorrect preimage", htlc_id)));
2069                                                 }
2070                                 };
2071                                 match htlc.state {
2072                                         OutboundHTLCState::LocalAnnounced(_) =>
2073                                                 return Err(ChannelError::Close(format!("Remote tried to fulfill/fail HTLC ({}) before it had been committed", htlc_id))),
2074                                         OutboundHTLCState::Committed => {
2075                                                 htlc.state = OutboundHTLCState::RemoteRemoved(fail_reason);
2076                                         },
2077                                         OutboundHTLCState::AwaitingRemoteRevokeToRemove(_) | OutboundHTLCState::AwaitingRemovedRemoteRevoke(_) | OutboundHTLCState::RemoteRemoved(_) =>
2078                                                 return Err(ChannelError::Close(format!("Remote tried to fulfill/fail HTLC ({}) that they'd already fulfilled/failed", htlc_id))),
2079                                 }
2080                                 return Ok(&htlc.source);
2081                         }
2082                 }
2083                 Err(ChannelError::Close("Remote tried to fulfill/fail an HTLC we couldn't find".to_owned()))
2084         }
2085
2086         pub fn update_fulfill_htlc(&mut self, msg: &msgs::UpdateFulfillHTLC) -> Result<HTLCSource, ChannelError> {
2087                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2088                         return Err(ChannelError::Close("Got fulfill HTLC message when channel was not in an operational state".to_owned()));
2089                 }
2090                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2091                         return Err(ChannelError::Close("Peer sent update_fulfill_htlc when we needed a channel_reestablish".to_owned()));
2092                 }
2093
2094                 let payment_hash = PaymentHash(Sha256::hash(&msg.payment_preimage.0[..]).into_inner());
2095                 self.mark_outbound_htlc_removed(msg.htlc_id, Some(payment_hash), None).map(|source| source.clone())
2096         }
2097
2098         pub fn update_fail_htlc(&mut self, msg: &msgs::UpdateFailHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> {
2099                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2100                         return Err(ChannelError::Close("Got fail HTLC message when channel was not in an operational state".to_owned()));
2101                 }
2102                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2103                         return Err(ChannelError::Close("Peer sent update_fail_htlc when we needed a channel_reestablish".to_owned()));
2104                 }
2105
2106                 self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason))?;
2107                 Ok(())
2108         }
2109
2110         pub fn update_fail_malformed_htlc(&mut self, msg: &msgs::UpdateFailMalformedHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> {
2111                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2112                         return Err(ChannelError::Close("Got fail malformed HTLC message when channel was not in an operational state".to_owned()));
2113                 }
2114                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2115                         return Err(ChannelError::Close("Peer sent update_fail_malformed_htlc when we needed a channel_reestablish".to_owned()));
2116                 }
2117
2118                 self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason))?;
2119                 Ok(())
2120         }
2121
2122         pub fn commitment_signed<F: Deref, L: Deref>(&mut self, msg: &msgs::CommitmentSigned, fee_estimator: &F, logger: &L) -> Result<(msgs::RevokeAndACK, Option<msgs::CommitmentSigned>, Option<msgs::ClosingSigned>, ChannelMonitorUpdate), (Option<ChannelMonitorUpdate>, ChannelError)>
2123         where F::Target: FeeEstimator,
2124                                 L::Target: Logger
2125         {
2126                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2127                         return Err((None, ChannelError::Close("Got commitment signed message when channel was not in an operational state".to_owned())));
2128                 }
2129                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2130                         return Err((None, ChannelError::Close("Peer sent commitment_signed when we needed a channel_reestablish".to_owned())));
2131                 }
2132                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() {
2133                         return Err((None, ChannelError::Close("Peer sent commitment_signed after we'd started exchanging closing_signeds".to_owned())));
2134                 }
2135
2136                 let funding_script = self.get_funding_redeemscript();
2137
2138                 let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number).map_err(|e| (None, e))?;
2139
2140                 let mut update_fee = false;
2141                 let feerate_per_kw = if !self.is_outbound() && self.pending_update_fee.is_some() {
2142                         update_fee = true;
2143                         self.pending_update_fee.unwrap()
2144                 } else {
2145                         self.feerate_per_kw
2146                 };
2147
2148                 let (num_htlcs, mut htlcs_cloned, commitment_tx, commitment_txid) = {
2149                         let commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, false, feerate_per_kw, logger);
2150                         let commitment_txid = {
2151                                 let trusted_tx = commitment_tx.0.trust();
2152                                 let bitcoin_tx = trusted_tx.built_transaction();
2153                                 let sighash = bitcoin_tx.get_sighash_all(&funding_script, self.channel_value_satoshis);
2154
2155                                 log_trace!(logger, "Checking commitment tx signature {} by key {} against tx {} (sighash {}) with redeemscript {}", log_bytes!(msg.signature.serialize_compact()[..]), log_bytes!(self.counterparty_funding_pubkey().serialize()), encode::serialize_hex(&bitcoin_tx.transaction), log_bytes!(sighash[..]), encode::serialize_hex(&funding_script));
2156                                 if let Err(_) = self.secp_ctx.verify(&sighash, &msg.signature, &self.counterparty_funding_pubkey()) {
2157                                         return Err((None, ChannelError::Close("Invalid commitment tx signature from peer".to_owned())));
2158                                 }
2159                                 bitcoin_tx.txid
2160                         };
2161                         let htlcs_cloned: Vec<_> = commitment_tx.2.iter().map(|htlc| (htlc.0.clone(), htlc.1.map(|h| h.clone()))).collect();
2162                         (commitment_tx.1, htlcs_cloned, commitment_tx.0, commitment_txid)
2163                 };
2164
2165                 let total_fee = feerate_per_kw as u64 * (COMMITMENT_TX_BASE_WEIGHT + (num_htlcs as u64) * COMMITMENT_TX_WEIGHT_PER_HTLC) / 1000;
2166                 //If channel fee was updated by funder confirm funder can afford the new fee rate when applied to the current local commitment transaction
2167                 if update_fee {
2168                         let counterparty_reserve_we_require = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis);
2169                         if self.channel_value_satoshis - self.value_to_self_msat / 1000 < total_fee + counterparty_reserve_we_require {
2170                                 return Err((None, ChannelError::Close("Funding remote cannot afford proposed new fee".to_owned())));
2171                         }
2172                 }
2173                 #[cfg(any(test, feature = "fuzztarget"))]
2174                 {
2175                         if self.is_outbound() {
2176                                 let projected_commit_tx_info = self.next_local_commitment_tx_fee_info_cached.lock().unwrap().take();
2177                                 *self.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = None;
2178                                 if let Some(info) = projected_commit_tx_info {
2179                                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len()
2180                                                 + self.holding_cell_htlc_updates.len();
2181                                         if info.total_pending_htlcs == total_pending_htlcs
2182                                                 && info.next_holder_htlc_id == self.next_holder_htlc_id
2183                                                 && info.next_counterparty_htlc_id == self.next_counterparty_htlc_id
2184                                                 && info.feerate == self.feerate_per_kw {
2185                                                         assert_eq!(total_fee, info.fee / 1000);
2186                                                 }
2187                                 }
2188                         }
2189                 }
2190
2191                 if msg.htlc_signatures.len() != num_htlcs {
2192                         return Err((None, ChannelError::Close(format!("Got wrong number of HTLC signatures ({}) from remote. It must be {}", msg.htlc_signatures.len(), num_htlcs))));
2193                 }
2194
2195                 // TODO: Sadly, we pass HTLCs twice to ChannelMonitor: once via the HolderCommitmentTransaction and once via the update
2196                 let mut htlcs_and_sigs = Vec::with_capacity(htlcs_cloned.len());
2197                 for (idx, (htlc, source)) in htlcs_cloned.drain(..).enumerate() {
2198                         if let Some(_) = htlc.transaction_output_index {
2199                                 let htlc_tx = self.build_htlc_transaction(&commitment_txid, &htlc, true, &keys, feerate_per_kw);
2200                                 let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys);
2201                                 let htlc_sighash = hash_to_message!(&bip143::SigHashCache::new(&htlc_tx).signature_hash(0, &htlc_redeemscript, htlc.amount_msat / 1000, SigHashType::All)[..]);
2202                                 log_trace!(logger, "Checking HTLC tx signature {} by key {} against tx {} (sighash {}) with redeemscript {}", log_bytes!(msg.htlc_signatures[idx].serialize_compact()[..]), log_bytes!(keys.countersignatory_htlc_key.serialize()), encode::serialize_hex(&htlc_tx), log_bytes!(htlc_sighash[..]), encode::serialize_hex(&htlc_redeemscript));
2203                                 if let Err(_) = self.secp_ctx.verify(&htlc_sighash, &msg.htlc_signatures[idx], &keys.countersignatory_htlc_key) {
2204                                         return Err((None, ChannelError::Close("Invalid HTLC tx signature from peer".to_owned())));
2205                                 }
2206                                 htlcs_and_sigs.push((htlc, Some(msg.htlc_signatures[idx]), source));
2207                         } else {
2208                                 htlcs_and_sigs.push((htlc, None, source));
2209                         }
2210                 }
2211
2212                 let holder_commitment_tx = HolderCommitmentTransaction::new(
2213                         commitment_tx,
2214                         msg.signature,
2215                         msg.htlc_signatures.clone(),
2216                         &self.get_holder_pubkeys().funding_pubkey,
2217                         self.counterparty_funding_pubkey()
2218                 );
2219
2220                 let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number - 1, &self.secp_ctx);
2221                 let per_commitment_secret = self.holder_signer.release_commitment_secret(self.cur_holder_commitment_transaction_number + 1);
2222
2223                 // Update state now that we've passed all the can-fail calls...
2224                 let mut need_commitment = false;
2225                 if !self.is_outbound() {
2226                         if let Some(fee_update) = self.pending_update_fee {
2227                                 self.feerate_per_kw = fee_update;
2228                                 // We later use the presence of pending_update_fee to indicate we should generate a
2229                                 // commitment_signed upon receipt of revoke_and_ack, so we can only set it to None
2230                                 // if we're not awaiting a revoke (ie will send a commitment_signed now).
2231                                 if (self.channel_state & ChannelState::AwaitingRemoteRevoke as u32) == 0 {
2232                                         need_commitment = true;
2233                                         self.pending_update_fee = None;
2234                                 }
2235                         }
2236                 }
2237
2238                 self.latest_monitor_update_id += 1;
2239                 let mut monitor_update = ChannelMonitorUpdate {
2240                         update_id: self.latest_monitor_update_id,
2241                         updates: vec![ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo {
2242                                 commitment_tx: holder_commitment_tx,
2243                                 htlc_outputs: htlcs_and_sigs
2244                         }]
2245                 };
2246
2247                 for htlc in self.pending_inbound_htlcs.iter_mut() {
2248                         let new_forward = if let &InboundHTLCState::RemoteAnnounced(ref forward_info) = &htlc.state {
2249                                 Some(forward_info.clone())
2250                         } else { None };
2251                         if let Some(forward_info) = new_forward {
2252                                 htlc.state = InboundHTLCState::AwaitingRemoteRevokeToAnnounce(forward_info);
2253                                 need_commitment = true;
2254                         }
2255                 }
2256                 for htlc in self.pending_outbound_htlcs.iter_mut() {
2257                         if let Some(fail_reason) = if let &mut OutboundHTLCState::RemoteRemoved(ref mut fail_reason) = &mut htlc.state {
2258                                 Some(fail_reason.take())
2259                         } else { None } {
2260                                 htlc.state = OutboundHTLCState::AwaitingRemoteRevokeToRemove(fail_reason);
2261                                 need_commitment = true;
2262                         }
2263                 }
2264
2265                 self.cur_holder_commitment_transaction_number -= 1;
2266                 // Note that if we need_commitment & !AwaitingRemoteRevoke we'll call
2267                 // send_commitment_no_status_check() next which will reset this to RAAFirst.
2268                 self.resend_order = RAACommitmentOrder::CommitmentFirst;
2269
2270                 if (self.channel_state & ChannelState::MonitorUpdateFailed as u32) != 0 {
2271                         // In case we initially failed monitor updating without requiring a response, we need
2272                         // to make sure the RAA gets sent first.
2273                         self.monitor_pending_revoke_and_ack = true;
2274                         if need_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 {
2275                                 // If we were going to send a commitment_signed after the RAA, go ahead and do all
2276                                 // the corresponding HTLC status updates so that get_last_commitment_update
2277                                 // includes the right HTLCs.
2278                                 self.monitor_pending_commitment_signed = true;
2279                                 let (_, mut additional_update) = self.send_commitment_no_status_check(logger).map_err(|e| (None, e))?;
2280                                 // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2281                                 // strictly increasing by one, so decrement it here.
2282                                 self.latest_monitor_update_id = monitor_update.update_id;
2283                                 monitor_update.updates.append(&mut additional_update.updates);
2284                         }
2285                         // TODO: Call maybe_propose_first_closing_signed on restoration (or call it here and
2286                         // re-send the message on restoration)
2287                         return Err((Some(monitor_update), ChannelError::Ignore("Previous monitor update failure prevented generation of RAA".to_owned())));
2288                 }
2289
2290                 let (commitment_signed, closing_signed) = if need_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 {
2291                         // If we're AwaitingRemoteRevoke we can't send a new commitment here, but that's ok -
2292                         // we'll send one right away when we get the revoke_and_ack when we
2293                         // free_holding_cell_htlcs().
2294                         let (msg, mut additional_update) = self.send_commitment_no_status_check(logger).map_err(|e| (None, e))?;
2295                         // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2296                         // strictly increasing by one, so decrement it here.
2297                         self.latest_monitor_update_id = monitor_update.update_id;
2298                         monitor_update.updates.append(&mut additional_update.updates);
2299                         (Some(msg), None)
2300                 } else if !need_commitment {
2301                         (None, self.maybe_propose_first_closing_signed(fee_estimator))
2302                 } else { (None, None) };
2303
2304                 Ok((msgs::RevokeAndACK {
2305                         channel_id: self.channel_id,
2306                         per_commitment_secret,
2307                         next_per_commitment_point,
2308                 }, commitment_signed, closing_signed, monitor_update))
2309         }
2310
2311         /// Used to fulfill holding_cell_htlcs when we get a remote ack (or implicitly get it by them
2312         /// fulfilling or failing the last pending HTLC)
2313         fn free_holding_cell_htlcs<L: Deref>(&mut self, logger: &L) -> Result<(Option<(msgs::CommitmentUpdate, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>), ChannelError> where L::Target: Logger {
2314                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, 0);
2315                 if self.holding_cell_htlc_updates.len() != 0 || self.holding_cell_update_fee.is_some() {
2316                         log_trace!(logger, "Freeing holding cell with {} HTLC updates{}", self.holding_cell_htlc_updates.len(), if self.holding_cell_update_fee.is_some() { " and a fee update" } else { "" });
2317
2318                         let mut monitor_update = ChannelMonitorUpdate {
2319                                 update_id: self.latest_monitor_update_id + 1, // We don't increment this yet!
2320                                 updates: Vec::new(),
2321                         };
2322
2323                         let mut htlc_updates = Vec::new();
2324                         mem::swap(&mut htlc_updates, &mut self.holding_cell_htlc_updates);
2325                         let mut update_add_htlcs = Vec::with_capacity(htlc_updates.len());
2326                         let mut update_fulfill_htlcs = Vec::with_capacity(htlc_updates.len());
2327                         let mut update_fail_htlcs = Vec::with_capacity(htlc_updates.len());
2328                         let mut htlcs_to_fail = Vec::new();
2329                         for htlc_update in htlc_updates.drain(..) {
2330                                 // Note that this *can* fail, though it should be due to rather-rare conditions on
2331                                 // fee races with adding too many outputs which push our total payments just over
2332                                 // the limit. In case it's less rare than I anticipate, we may want to revisit
2333                                 // handling this case better and maybe fulfilling some of the HTLCs while attempting
2334                                 // to rebalance channels.
2335                                 match &htlc_update {
2336                                         &HTLCUpdateAwaitingACK::AddHTLC {amount_msat, cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet, ..} => {
2337                                                 match self.send_htlc(amount_msat, *payment_hash, cltv_expiry, source.clone(), onion_routing_packet.clone()) {
2338                                                         Ok(update_add_msg_option) => update_add_htlcs.push(update_add_msg_option.unwrap()),
2339                                                         Err(e) => {
2340                                                                 match e {
2341                                                                         ChannelError::Ignore(ref msg) => {
2342                                                                                 log_info!(logger, "Failed to send HTLC with payment_hash {} due to {}", log_bytes!(payment_hash.0), msg);
2343                                                                                 // If we fail to send here, then this HTLC should
2344                                                                                 // be failed backwards. Failing to send here
2345                                                                                 // indicates that this HTLC may keep being put back
2346                                                                                 // into the holding cell without ever being
2347                                                                                 // successfully forwarded/failed/fulfilled, causing
2348                                                                                 // our counterparty to eventually close on us.
2349                                                                                 htlcs_to_fail.push((source.clone(), *payment_hash));
2350                                                                         },
2351                                                                         _ => {
2352                                                                                 panic!("Got a non-IgnoreError action trying to send holding cell HTLC");
2353                                                                         },
2354                                                                 }
2355                                                         }
2356                                                 }
2357                                         },
2358                                         &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, htlc_id, .. } => {
2359                                                 match self.get_update_fulfill_htlc(htlc_id, *payment_preimage, logger) {
2360                                                         Ok((update_fulfill_msg_option, additional_monitor_update_opt)) => {
2361                                                                 update_fulfill_htlcs.push(update_fulfill_msg_option.unwrap());
2362                                                                 if let Some(mut additional_monitor_update) = additional_monitor_update_opt {
2363                                                                         monitor_update.updates.append(&mut additional_monitor_update.updates);
2364                                                                 }
2365                                                         },
2366                                                         Err(e) => {
2367                                                                 if let ChannelError::Ignore(_) = e {}
2368                                                                 else {
2369                                                                         panic!("Got a non-IgnoreError action trying to fulfill holding cell HTLC");
2370                                                                 }
2371                                                         }
2372                                                 }
2373                                         },
2374                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, ref err_packet } => {
2375                                                 match self.get_update_fail_htlc(htlc_id, err_packet.clone()) {
2376                                                         Ok(update_fail_msg_option) => update_fail_htlcs.push(update_fail_msg_option.unwrap()),
2377                                                         Err(e) => {
2378                                                                 if let ChannelError::Ignore(_) = e {}
2379                                                                 else {
2380                                                                         panic!("Got a non-IgnoreError action trying to fail holding cell HTLC");
2381                                                                 }
2382                                                         }
2383                                                 }
2384                                         },
2385                                 }
2386                         }
2387                         if update_add_htlcs.is_empty() && update_fulfill_htlcs.is_empty() && update_fail_htlcs.is_empty() && self.holding_cell_update_fee.is_none() {
2388                                 return Ok((None, htlcs_to_fail));
2389                         }
2390                         let update_fee = if let Some(feerate) = self.holding_cell_update_fee {
2391                                 self.pending_update_fee = self.holding_cell_update_fee.take();
2392                                 Some(msgs::UpdateFee {
2393                                         channel_id: self.channel_id,
2394                                         feerate_per_kw: feerate as u32,
2395                                 })
2396                         } else {
2397                                 None
2398                         };
2399
2400                         let (commitment_signed, mut additional_update) = self.send_commitment_no_status_check(logger)?;
2401                         // send_commitment_no_status_check and get_update_fulfill_htlc may bump latest_monitor_id
2402                         // but we want them to be strictly increasing by one, so reset it here.
2403                         self.latest_monitor_update_id = monitor_update.update_id;
2404                         monitor_update.updates.append(&mut additional_update.updates);
2405
2406                         Ok((Some((msgs::CommitmentUpdate {
2407                                 update_add_htlcs,
2408                                 update_fulfill_htlcs,
2409                                 update_fail_htlcs,
2410                                 update_fail_malformed_htlcs: Vec::new(),
2411                                 update_fee,
2412                                 commitment_signed,
2413                         }, monitor_update)), htlcs_to_fail))
2414                 } else {
2415                         Ok((None, Vec::new()))
2416                 }
2417         }
2418
2419         /// Handles receiving a remote's revoke_and_ack. Note that we may return a new
2420         /// commitment_signed message here in case we had pending outbound HTLCs to add which were
2421         /// waiting on this revoke_and_ack. The generation of this new commitment_signed may also fail,
2422         /// generating an appropriate error *after* the channel state has been updated based on the
2423         /// revoke_and_ack message.
2424         pub fn revoke_and_ack<F: Deref, L: Deref>(&mut self, msg: &msgs::RevokeAndACK, fee_estimator: &F, logger: &L) -> Result<(Option<msgs::CommitmentUpdate>, Vec<(PendingHTLCInfo, u64)>, Vec<(HTLCSource, PaymentHash, HTLCFailReason)>, Option<msgs::ClosingSigned>, ChannelMonitorUpdate, Vec<(HTLCSource, PaymentHash)>), ChannelError>
2425                 where F::Target: FeeEstimator,
2426                                         L::Target: Logger,
2427         {
2428                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2429                         return Err(ChannelError::Close("Got revoke/ACK message when channel was not in an operational state".to_owned()));
2430                 }
2431                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2432                         return Err(ChannelError::Close("Peer sent revoke_and_ack when we needed a channel_reestablish".to_owned()));
2433                 }
2434                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() {
2435                         return Err(ChannelError::Close("Peer sent revoke_and_ack after we'd started exchanging closing_signeds".to_owned()));
2436                 }
2437
2438                 if let Some(counterparty_prev_commitment_point) = self.counterparty_prev_commitment_point {
2439                         if PublicKey::from_secret_key(&self.secp_ctx, &secp_check!(SecretKey::from_slice(&msg.per_commitment_secret), "Peer provided an invalid per_commitment_secret".to_owned())) != counterparty_prev_commitment_point {
2440                                 return Err(ChannelError::Close("Got a revoke commitment secret which didn't correspond to their current pubkey".to_owned()));
2441                         }
2442                 }
2443
2444                 if self.channel_state & ChannelState::AwaitingRemoteRevoke as u32 == 0 {
2445                         // Our counterparty seems to have burned their coins to us (by revoking a state when we
2446                         // haven't given them a new commitment transaction to broadcast). We should probably
2447                         // take advantage of this by updating our channel monitor, sending them an error, and
2448                         // waiting for them to broadcast their latest (now-revoked claim). But, that would be a
2449                         // lot of work, and there's some chance this is all a misunderstanding anyway.
2450                         // We have to do *something*, though, since our signer may get mad at us for otherwise
2451                         // jumping a remote commitment number, so best to just force-close and move on.
2452                         return Err(ChannelError::Close("Received an unexpected revoke_and_ack".to_owned()));
2453                 }
2454
2455                 #[cfg(any(test, feature = "fuzztarget"))]
2456                 {
2457                         *self.next_local_commitment_tx_fee_info_cached.lock().unwrap() = None;
2458                         *self.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = None;
2459                 }
2460
2461                 self.commitment_secrets.provide_secret(self.cur_counterparty_commitment_transaction_number + 1, msg.per_commitment_secret)
2462                         .map_err(|_| ChannelError::Close("Previous secrets did not match new one".to_owned()))?;
2463                 self.latest_monitor_update_id += 1;
2464                 let mut monitor_update = ChannelMonitorUpdate {
2465                         update_id: self.latest_monitor_update_id,
2466                         updates: vec![ChannelMonitorUpdateStep::CommitmentSecret {
2467                                 idx: self.cur_counterparty_commitment_transaction_number + 1,
2468                                 secret: msg.per_commitment_secret,
2469                         }],
2470                 };
2471
2472                 // Update state now that we've passed all the can-fail calls...
2473                 // (note that we may still fail to generate the new commitment_signed message, but that's
2474                 // OK, we step the channel here and *then* if the new generation fails we can fail the
2475                 // channel based on that, but stepping stuff here should be safe either way.
2476                 self.channel_state &= !(ChannelState::AwaitingRemoteRevoke as u32);
2477                 self.counterparty_prev_commitment_point = self.counterparty_cur_commitment_point;
2478                 self.counterparty_cur_commitment_point = Some(msg.next_per_commitment_point);
2479                 self.cur_counterparty_commitment_transaction_number -= 1;
2480
2481                 log_trace!(logger, "Updating HTLCs on receipt of RAA...");
2482                 let mut to_forward_infos = Vec::new();
2483                 let mut revoked_htlcs = Vec::new();
2484                 let mut update_fail_htlcs = Vec::new();
2485                 let mut update_fail_malformed_htlcs = Vec::new();
2486                 let mut require_commitment = false;
2487                 let mut value_to_self_msat_diff: i64 = 0;
2488
2489                 {
2490                         // Take references explicitly so that we can hold multiple references to self.
2491                         let pending_inbound_htlcs: &mut Vec<_> = &mut self.pending_inbound_htlcs;
2492                         let pending_outbound_htlcs: &mut Vec<_> = &mut self.pending_outbound_htlcs;
2493
2494                         // We really shouldnt have two passes here, but retain gives a non-mutable ref (Rust bug)
2495                         pending_inbound_htlcs.retain(|htlc| {
2496                                 if let &InboundHTLCState::LocalRemoved(ref reason) = &htlc.state {
2497                                         log_trace!(logger, " ...removing inbound LocalRemoved {}", log_bytes!(htlc.payment_hash.0));
2498                                         if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
2499                                                 value_to_self_msat_diff += htlc.amount_msat as i64;
2500                                         }
2501                                         false
2502                                 } else { true }
2503                         });
2504                         pending_outbound_htlcs.retain(|htlc| {
2505                                 if let &OutboundHTLCState::AwaitingRemovedRemoteRevoke(ref fail_reason) = &htlc.state {
2506                                         log_trace!(logger, " ...removing outbound AwaitingRemovedRemoteRevoke {}", log_bytes!(htlc.payment_hash.0));
2507                                         if let Some(reason) = fail_reason.clone() { // We really want take() here, but, again, non-mut ref :(
2508                                                 revoked_htlcs.push((htlc.source.clone(), htlc.payment_hash, reason));
2509                                         } else {
2510                                                 // They fulfilled, so we sent them money
2511                                                 value_to_self_msat_diff -= htlc.amount_msat as i64;
2512                                         }
2513                                         false
2514                                 } else { true }
2515                         });
2516                         for htlc in pending_inbound_htlcs.iter_mut() {
2517                                 let swap = if let &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_) = &htlc.state {
2518                                         log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce {} to Committed", log_bytes!(htlc.payment_hash.0));
2519                                         true
2520                                 } else if let &InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) = &htlc.state {
2521                                         log_trace!(logger, " ...promoting inbound AwaitingAnnouncedRemoteRevoke {} to Committed", log_bytes!(htlc.payment_hash.0));
2522                                         true
2523                                 } else { false };
2524                                 if swap {
2525                                         let mut state = InboundHTLCState::Committed;
2526                                         mem::swap(&mut state, &mut htlc.state);
2527
2528                                         if let InboundHTLCState::AwaitingRemoteRevokeToAnnounce(forward_info) = state {
2529                                                 htlc.state = InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info);
2530                                                 require_commitment = true;
2531                                         } else if let InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info) = state {
2532                                                 match forward_info {
2533                                                         PendingHTLCStatus::Fail(fail_msg) => {
2534                                                                 require_commitment = true;
2535                                                                 match fail_msg {
2536                                                                         HTLCFailureMsg::Relay(msg) => {
2537                                                                                 htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(msg.reason.clone()));
2538                                                                                 update_fail_htlcs.push(msg)
2539                                                                         },
2540                                                                         HTLCFailureMsg::Malformed(msg) => {
2541                                                                                 htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailMalformed((msg.sha256_of_onion, msg.failure_code)));
2542                                                                                 update_fail_malformed_htlcs.push(msg)
2543                                                                         },
2544                                                                 }
2545                                                         },
2546                                                         PendingHTLCStatus::Forward(forward_info) => {
2547                                                                 to_forward_infos.push((forward_info, htlc.htlc_id));
2548                                                                 htlc.state = InboundHTLCState::Committed;
2549                                                         }
2550                                                 }
2551                                         }
2552                                 }
2553                         }
2554                         for htlc in pending_outbound_htlcs.iter_mut() {
2555                                 if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
2556                                         log_trace!(logger, " ...promoting outbound LocalAnnounced {} to Committed", log_bytes!(htlc.payment_hash.0));
2557                                         htlc.state = OutboundHTLCState::Committed;
2558                                 }
2559                                 if let Some(fail_reason) = if let &mut OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref mut fail_reason) = &mut htlc.state {
2560                                         Some(fail_reason.take())
2561                                 } else { None } {
2562                                         log_trace!(logger, " ...promoting outbound AwaitingRemoteRevokeToRemove {} to AwaitingRemovedRemoteRevoke", log_bytes!(htlc.payment_hash.0));
2563                                         htlc.state = OutboundHTLCState::AwaitingRemovedRemoteRevoke(fail_reason);
2564                                         require_commitment = true;
2565                                 }
2566                         }
2567                 }
2568                 self.value_to_self_msat = (self.value_to_self_msat as i64 + value_to_self_msat_diff) as u64;
2569
2570                 if self.is_outbound() {
2571                         if let Some(feerate) = self.pending_update_fee.take() {
2572                                 self.feerate_per_kw = feerate;
2573                         }
2574                 } else {
2575                         if let Some(feerate) = self.pending_update_fee {
2576                                 // Because a node cannot send two commitment_signeds in a row without getting a
2577                                 // revoke_and_ack from us (as it would otherwise not know the per_commitment_point
2578                                 // it should use to create keys with) and because a node can't send a
2579                                 // commitment_signed without changes, checking if the feerate is equal to the
2580                                 // pending feerate update is sufficient to detect require_commitment.
2581                                 if feerate == self.feerate_per_kw {
2582                                         require_commitment = true;
2583                                         self.pending_update_fee = None;
2584                                 }
2585                         }
2586                 }
2587
2588                 if (self.channel_state & ChannelState::MonitorUpdateFailed as u32) == ChannelState::MonitorUpdateFailed as u32 {
2589                         // We can't actually generate a new commitment transaction (incl by freeing holding
2590                         // cells) while we can't update the monitor, so we just return what we have.
2591                         if require_commitment {
2592                                 self.monitor_pending_commitment_signed = true;
2593                                 // When the monitor updating is restored we'll call get_last_commitment_update(),
2594                                 // which does not update state, but we're definitely now awaiting a remote revoke
2595                                 // before we can step forward any more, so set it here.
2596                                 let (_, mut additional_update) = self.send_commitment_no_status_check(logger)?;
2597                                 // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2598                                 // strictly increasing by one, so decrement it here.
2599                                 self.latest_monitor_update_id = monitor_update.update_id;
2600                                 monitor_update.updates.append(&mut additional_update.updates);
2601                         }
2602                         self.monitor_pending_forwards.append(&mut to_forward_infos);
2603                         self.monitor_pending_failures.append(&mut revoked_htlcs);
2604                         return Ok((None, Vec::new(), Vec::new(), None, monitor_update, Vec::new()))
2605                 }
2606
2607                 match self.free_holding_cell_htlcs(logger)? {
2608                         (Some((mut commitment_update, mut additional_update)), htlcs_to_fail) => {
2609                                 commitment_update.update_fail_htlcs.reserve(update_fail_htlcs.len());
2610                                 for fail_msg in update_fail_htlcs.drain(..) {
2611                                         commitment_update.update_fail_htlcs.push(fail_msg);
2612                                 }
2613                                 commitment_update.update_fail_malformed_htlcs.reserve(update_fail_malformed_htlcs.len());
2614                                 for fail_msg in update_fail_malformed_htlcs.drain(..) {
2615                                         commitment_update.update_fail_malformed_htlcs.push(fail_msg);
2616                                 }
2617
2618                                 // free_holding_cell_htlcs may bump latest_monitor_id multiple times but we want them to be
2619                                 // strictly increasing by one, so decrement it here.
2620                                 self.latest_monitor_update_id = monitor_update.update_id;
2621                                 monitor_update.updates.append(&mut additional_update.updates);
2622
2623                                 Ok((Some(commitment_update), to_forward_infos, revoked_htlcs, None, monitor_update, htlcs_to_fail))
2624                         },
2625                         (None, htlcs_to_fail) => {
2626                                 if require_commitment {
2627                                         let (commitment_signed, mut additional_update) = self.send_commitment_no_status_check(logger)?;
2628
2629                                         // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2630                                         // strictly increasing by one, so decrement it here.
2631                                         self.latest_monitor_update_id = monitor_update.update_id;
2632                                         monitor_update.updates.append(&mut additional_update.updates);
2633
2634                                         Ok((Some(msgs::CommitmentUpdate {
2635                                                 update_add_htlcs: Vec::new(),
2636                                                 update_fulfill_htlcs: Vec::new(),
2637                                                 update_fail_htlcs,
2638                                                 update_fail_malformed_htlcs,
2639                                                 update_fee: None,
2640                                                 commitment_signed
2641                                         }), to_forward_infos, revoked_htlcs, None, monitor_update, htlcs_to_fail))
2642                                 } else {
2643                                         Ok((None, to_forward_infos, revoked_htlcs, self.maybe_propose_first_closing_signed(fee_estimator), monitor_update, htlcs_to_fail))
2644                                 }
2645                         }
2646                 }
2647
2648         }
2649
2650         /// Adds a pending update to this channel. See the doc for send_htlc for
2651         /// further details on the optionness of the return value.
2652         /// You MUST call send_commitment prior to any other calls on this Channel
2653         fn send_update_fee(&mut self, feerate_per_kw: u32) -> Option<msgs::UpdateFee> {
2654                 if !self.is_outbound() {
2655                         panic!("Cannot send fee from inbound channel");
2656                 }
2657                 if !self.is_usable() {
2658                         panic!("Cannot update fee until channel is fully established and we haven't started shutting down");
2659                 }
2660                 if !self.is_live() {
2661                         panic!("Cannot update fee while peer is disconnected/we're awaiting a monitor update (ChannelManager should have caught this)");
2662                 }
2663
2664                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
2665                         self.holding_cell_update_fee = Some(feerate_per_kw);
2666                         return None;
2667                 }
2668
2669                 debug_assert!(self.pending_update_fee.is_none());
2670                 self.pending_update_fee = Some(feerate_per_kw);
2671
2672                 Some(msgs::UpdateFee {
2673                         channel_id: self.channel_id,
2674                         feerate_per_kw,
2675                 })
2676         }
2677
2678         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 {
2679                 match self.send_update_fee(feerate_per_kw) {
2680                         Some(update_fee) => {
2681                                 let (commitment_signed, monitor_update) = self.send_commitment_no_status_check(logger)?;
2682                                 Ok(Some((update_fee, commitment_signed, monitor_update)))
2683                         },
2684                         None => Ok(None)
2685                 }
2686         }
2687
2688         /// Removes any uncommitted HTLCs, to be used on peer disconnection, including any pending
2689         /// HTLCs that we intended to add but haven't as we were waiting on a remote revoke.
2690         /// Returns the set of PendingHTLCStatuses from remote uncommitted HTLCs (which we're
2691         /// implicitly dropping) and the payment_hashes of HTLCs we tried to add but are dropping.
2692         /// No further message handling calls may be made until a channel_reestablish dance has
2693         /// completed.
2694         pub fn remove_uncommitted_htlcs_and_mark_paused<L: Deref>(&mut self, logger: &L) -> Vec<(HTLCSource, PaymentHash)> where L::Target: Logger {
2695                 let mut outbound_drops = Vec::new();
2696
2697                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
2698                 if self.channel_state < ChannelState::FundingSent as u32 {
2699                         self.channel_state = ChannelState::ShutdownComplete as u32;
2700                         return outbound_drops;
2701                 }
2702                 // Upon reconnect we have to start the closing_signed dance over, but shutdown messages
2703                 // will be retransmitted.
2704                 self.last_sent_closing_fee = None;
2705
2706                 let mut inbound_drop_count = 0;
2707                 self.pending_inbound_htlcs.retain(|htlc| {
2708                         match htlc.state {
2709                                 InboundHTLCState::RemoteAnnounced(_) => {
2710                                         // They sent us an update_add_htlc but we never got the commitment_signed.
2711                                         // We'll tell them what commitment_signed we're expecting next and they'll drop
2712                                         // this HTLC accordingly
2713                                         inbound_drop_count += 1;
2714                                         false
2715                                 },
2716                                 InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_)|InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) => {
2717                                         // We received a commitment_signed updating this HTLC and (at least hopefully)
2718                                         // sent a revoke_and_ack (which we can re-transmit) and have heard nothing
2719                                         // in response to it yet, so don't touch it.
2720                                         true
2721                                 },
2722                                 InboundHTLCState::Committed => true,
2723                                 InboundHTLCState::LocalRemoved(_) => {
2724                                         // We (hopefully) sent a commitment_signed updating this HTLC (which we can
2725                                         // re-transmit if needed) and they may have even sent a revoke_and_ack back
2726                                         // (that we missed). Keep this around for now and if they tell us they missed
2727                                         // the commitment_signed we can re-transmit the update then.
2728                                         true
2729                                 },
2730                         }
2731                 });
2732                 self.next_counterparty_htlc_id -= inbound_drop_count;
2733
2734                 for htlc in self.pending_outbound_htlcs.iter_mut() {
2735                         if let OutboundHTLCState::RemoteRemoved(_) = htlc.state {
2736                                 // They sent us an update to remove this but haven't yet sent the corresponding
2737                                 // commitment_signed, we need to move it back to Committed and they can re-send
2738                                 // the update upon reconnection.
2739                                 htlc.state = OutboundHTLCState::Committed;
2740                         }
2741                 }
2742
2743                 self.holding_cell_htlc_updates.retain(|htlc_update| {
2744                         match htlc_update {
2745                                 // Note that currently on channel reestablish we assert that there are
2746                                 // no holding cell HTLC update_adds, so if in the future we stop
2747                                 // dropping added HTLCs here and failing them backwards, then there will
2748                                 // need to be corresponding changes made in the Channel's re-establish
2749                                 // logic.
2750                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
2751                                         outbound_drops.push((source.clone(), payment_hash.clone()));
2752                                         false
2753                                 },
2754                                 &HTLCUpdateAwaitingACK::ClaimHTLC {..} | &HTLCUpdateAwaitingACK::FailHTLC {..} => true,
2755                         }
2756                 });
2757                 self.channel_state |= ChannelState::PeerDisconnected as u32;
2758                 log_debug!(logger, "Peer disconnection resulted in {} remote-announced HTLC drops and {} waiting-to-locally-announced HTLC drops on channel {}", outbound_drops.len(), inbound_drop_count, log_bytes!(self.channel_id()));
2759                 outbound_drops
2760         }
2761
2762         /// Indicates that a ChannelMonitor update failed to be stored by the client and further
2763         /// updates are partially paused.
2764         /// This must be called immediately after the call which generated the ChannelMonitor update
2765         /// which failed. The messages which were generated from that call which generated the
2766         /// monitor update failure must *not* have been sent to the remote end, and must instead
2767         /// have been dropped. They will be regenerated when monitor_updating_restored is called.
2768         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)>) {
2769                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, 0);
2770                 self.monitor_pending_revoke_and_ack = resend_raa;
2771                 self.monitor_pending_commitment_signed = resend_commitment;
2772                 assert!(self.monitor_pending_forwards.is_empty());
2773                 mem::swap(&mut pending_forwards, &mut self.monitor_pending_forwards);
2774                 assert!(self.monitor_pending_failures.is_empty());
2775                 mem::swap(&mut pending_fails, &mut self.monitor_pending_failures);
2776                 self.channel_state |= ChannelState::MonitorUpdateFailed as u32;
2777         }
2778
2779         /// Indicates that the latest ChannelMonitor update has been committed by the client
2780         /// successfully and we should restore normal operation. Returns messages which should be sent
2781         /// to the remote side.
2782         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 {
2783                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, ChannelState::MonitorUpdateFailed as u32);
2784                 self.channel_state &= !(ChannelState::MonitorUpdateFailed as u32);
2785
2786                 let funding_broadcastable = if self.channel_state & (ChannelState::FundingSent as u32) != 0 && self.is_outbound() {
2787                         self.funding_transaction.take()
2788                 } else { None };
2789
2790                 // We will never broadcast the funding transaction when we're in MonitorUpdateFailed (and
2791                 // we assume the user never directly broadcasts the funding transaction and waits for us to
2792                 // do it). Thus, we can only ever hit monitor_pending_funding_locked when we're an inbound
2793                 // channel which failed to persist the monitor on funding_created, and we got the funding
2794                 // transaction confirmed before the monitor was persisted.
2795                 let funding_locked = if self.monitor_pending_funding_locked {
2796                         assert!(!self.is_outbound(), "Funding transaction broadcast by the local client before it should have - LDK didn't do it!");
2797                         self.monitor_pending_funding_locked = false;
2798                         let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
2799                         Some(msgs::FundingLocked {
2800                                 channel_id: self.channel_id(),
2801                                 next_per_commitment_point,
2802                         })
2803                 } else { None };
2804
2805                 let mut forwards = Vec::new();
2806                 mem::swap(&mut forwards, &mut self.monitor_pending_forwards);
2807                 let mut failures = Vec::new();
2808                 mem::swap(&mut failures, &mut self.monitor_pending_failures);
2809
2810                 if self.channel_state & (ChannelState::PeerDisconnected as u32) != 0 {
2811                         self.monitor_pending_revoke_and_ack = false;
2812                         self.monitor_pending_commitment_signed = false;
2813                         return (None, None, RAACommitmentOrder::RevokeAndACKFirst, forwards, failures, funding_broadcastable, funding_locked);
2814                 }
2815
2816                 let raa = if self.monitor_pending_revoke_and_ack {
2817                         Some(self.get_last_revoke_and_ack())
2818                 } else { None };
2819                 let commitment_update = if self.monitor_pending_commitment_signed {
2820                         Some(self.get_last_commitment_update(logger))
2821                 } else { None };
2822
2823                 self.monitor_pending_revoke_and_ack = false;
2824                 self.monitor_pending_commitment_signed = false;
2825                 let order = self.resend_order.clone();
2826                 log_trace!(logger, "Restored monitor updating resulting in {}{} commitment update and {} RAA, with {} first",
2827                         if funding_broadcastable.is_some() { "a funding broadcastable, " } else { "" },
2828                         if commitment_update.is_some() { "a" } else { "no" },
2829                         if raa.is_some() { "an" } else { "no" },
2830                         match order { RAACommitmentOrder::CommitmentFirst => "commitment", RAACommitmentOrder::RevokeAndACKFirst => "RAA"});
2831                 (raa, commitment_update, order, forwards, failures, funding_broadcastable, funding_locked)
2832         }
2833
2834         pub fn update_fee<F: Deref>(&mut self, fee_estimator: &F, msg: &msgs::UpdateFee) -> Result<(), ChannelError>
2835                 where F::Target: FeeEstimator
2836         {
2837                 if self.is_outbound() {
2838                         return Err(ChannelError::Close("Non-funding remote tried to update channel fee".to_owned()));
2839                 }
2840                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2841                         return Err(ChannelError::Close("Peer sent update_fee when we needed a channel_reestablish".to_owned()));
2842                 }
2843                 Channel::<Signer>::check_remote_fee(fee_estimator, msg.feerate_per_kw)?;
2844                 self.pending_update_fee = Some(msg.feerate_per_kw);
2845                 self.update_time_counter += 1;
2846                 Ok(())
2847         }
2848
2849         fn get_last_revoke_and_ack(&self) -> msgs::RevokeAndACK {
2850                 let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
2851                 let per_commitment_secret = self.holder_signer.release_commitment_secret(self.cur_holder_commitment_transaction_number + 2);
2852                 msgs::RevokeAndACK {
2853                         channel_id: self.channel_id,
2854                         per_commitment_secret,
2855                         next_per_commitment_point,
2856                 }
2857         }
2858
2859         fn get_last_commitment_update<L: Deref>(&self, logger: &L) -> msgs::CommitmentUpdate where L::Target: Logger {
2860                 let mut update_add_htlcs = Vec::new();
2861                 let mut update_fulfill_htlcs = Vec::new();
2862                 let mut update_fail_htlcs = Vec::new();
2863                 let mut update_fail_malformed_htlcs = Vec::new();
2864
2865                 for htlc in self.pending_outbound_htlcs.iter() {
2866                         if let &OutboundHTLCState::LocalAnnounced(ref onion_packet) = &htlc.state {
2867                                 update_add_htlcs.push(msgs::UpdateAddHTLC {
2868                                         channel_id: self.channel_id(),
2869                                         htlc_id: htlc.htlc_id,
2870                                         amount_msat: htlc.amount_msat,
2871                                         payment_hash: htlc.payment_hash,
2872                                         cltv_expiry: htlc.cltv_expiry,
2873                                         onion_routing_packet: (**onion_packet).clone(),
2874                                 });
2875                         }
2876                 }
2877
2878                 for htlc in self.pending_inbound_htlcs.iter() {
2879                         if let &InboundHTLCState::LocalRemoved(ref reason) = &htlc.state {
2880                                 match reason {
2881                                         &InboundHTLCRemovalReason::FailRelay(ref err_packet) => {
2882                                                 update_fail_htlcs.push(msgs::UpdateFailHTLC {
2883                                                         channel_id: self.channel_id(),
2884                                                         htlc_id: htlc.htlc_id,
2885                                                         reason: err_packet.clone()
2886                                                 });
2887                                         },
2888                                         &InboundHTLCRemovalReason::FailMalformed((ref sha256_of_onion, ref failure_code)) => {
2889                                                 update_fail_malformed_htlcs.push(msgs::UpdateFailMalformedHTLC {
2890                                                         channel_id: self.channel_id(),
2891                                                         htlc_id: htlc.htlc_id,
2892                                                         sha256_of_onion: sha256_of_onion.clone(),
2893                                                         failure_code: failure_code.clone(),
2894                                                 });
2895                                         },
2896                                         &InboundHTLCRemovalReason::Fulfill(ref payment_preimage) => {
2897                                                 update_fulfill_htlcs.push(msgs::UpdateFulfillHTLC {
2898                                                         channel_id: self.channel_id(),
2899                                                         htlc_id: htlc.htlc_id,
2900                                                         payment_preimage: payment_preimage.clone(),
2901                                                 });
2902                                         },
2903                                 }
2904                         }
2905                 }
2906
2907                 log_trace!(logger, "Regenerated latest commitment update with {} update_adds, {} update_fulfills, {} update_fails, and {} update_fail_malformeds",
2908                                 update_add_htlcs.len(), update_fulfill_htlcs.len(), update_fail_htlcs.len(), update_fail_malformed_htlcs.len());
2909                 msgs::CommitmentUpdate {
2910                         update_add_htlcs, update_fulfill_htlcs, update_fail_htlcs, update_fail_malformed_htlcs,
2911                         update_fee: None,
2912                         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,
2913                 }
2914         }
2915
2916         /// May panic if some calls other than message-handling calls (which will all Err immediately)
2917         /// have been called between remove_uncommitted_htlcs_and_mark_paused and this call.
2918         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, Option<msgs::Shutdown>), ChannelError> where L::Target: Logger {
2919                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == 0 {
2920                         // While BOLT 2 doesn't indicate explicitly we should error this channel here, it
2921                         // almost certainly indicates we are going to end up out-of-sync in some way, so we
2922                         // just close here instead of trying to recover.
2923                         return Err(ChannelError::Close("Peer sent a loose channel_reestablish not after reconnect".to_owned()));
2924                 }
2925
2926                 if msg.next_local_commitment_number >= INITIAL_COMMITMENT_NUMBER || msg.next_remote_commitment_number >= INITIAL_COMMITMENT_NUMBER ||
2927                         msg.next_local_commitment_number == 0 {
2928                         return Err(ChannelError::Close("Peer sent a garbage channel_reestablish".to_owned()));
2929                 }
2930
2931                 if msg.next_remote_commitment_number > 0 {
2932                         match msg.data_loss_protect {
2933                                 OptionalField::Present(ref data_loss) => {
2934                                         let expected_point = self.holder_signer.get_per_commitment_point(INITIAL_COMMITMENT_NUMBER - msg.next_remote_commitment_number + 1, &self.secp_ctx);
2935                                         let given_secret = SecretKey::from_slice(&data_loss.your_last_per_commitment_secret)
2936                                                 .map_err(|_| ChannelError::Close("Peer sent a garbage channel_reestablish with unparseable secret key".to_owned()))?;
2937                                         if expected_point != PublicKey::from_secret_key(&self.secp_ctx, &given_secret) {
2938                                                 return Err(ChannelError::Close("Peer sent a garbage channel_reestablish with secret key not matching the commitment height provided".to_owned()));
2939                                         }
2940                                         if msg.next_remote_commitment_number > INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number {
2941                                                 return Err(ChannelError::CloseDelayBroadcast(
2942                                                         "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()
2943                                                 ));
2944                                         }
2945                                 },
2946                                 OptionalField::Absent => {}
2947                         }
2948                 }
2949
2950                 // Go ahead and unmark PeerDisconnected as various calls we may make check for it (and all
2951                 // remaining cases either succeed or ErrorMessage-fail).
2952                 self.channel_state &= !(ChannelState::PeerDisconnected as u32);
2953
2954                 let shutdown_msg = if self.channel_state & (ChannelState::LocalShutdownSent as u32) != 0 {
2955                         Some(msgs::Shutdown {
2956                                 channel_id: self.channel_id,
2957                                 scriptpubkey: self.get_closing_scriptpubkey(),
2958                         })
2959                 } else { None };
2960
2961                 if self.channel_state & (ChannelState::FundingSent as u32) == ChannelState::FundingSent as u32 {
2962                         // If we're waiting on a monitor update, we shouldn't re-send any funding_locked's.
2963                         if self.channel_state & (ChannelState::OurFundingLocked as u32) == 0 ||
2964                                         self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
2965                                 if msg.next_remote_commitment_number != 0 {
2966                                         return Err(ChannelError::Close("Peer claimed they saw a revoke_and_ack but we haven't sent funding_locked yet".to_owned()));
2967                                 }
2968                                 // Short circuit the whole handler as there is nothing we can resend them
2969                                 return Ok((None, None, None, None, RAACommitmentOrder::CommitmentFirst, shutdown_msg));
2970                         }
2971
2972                         // We have OurFundingLocked set!
2973                         let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
2974                         return Ok((Some(msgs::FundingLocked {
2975                                 channel_id: self.channel_id(),
2976                                 next_per_commitment_point,
2977                         }), None, None, None, RAACommitmentOrder::CommitmentFirst, shutdown_msg));
2978                 }
2979
2980                 let required_revoke = if msg.next_remote_commitment_number + 1 == INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number {
2981                         // Remote isn't waiting on any RevokeAndACK from us!
2982                         // Note that if we need to repeat our FundingLocked we'll do that in the next if block.
2983                         None
2984                 } else if msg.next_remote_commitment_number + 1 == (INITIAL_COMMITMENT_NUMBER - 1) - self.cur_holder_commitment_transaction_number {
2985                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
2986                                 self.monitor_pending_revoke_and_ack = true;
2987                                 None
2988                         } else {
2989                                 Some(self.get_last_revoke_and_ack())
2990                         }
2991                 } else {
2992                         return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old local commitment transaction".to_owned()));
2993                 };
2994
2995                 // We increment cur_counterparty_commitment_transaction_number only upon receipt of
2996                 // revoke_and_ack, not on sending commitment_signed, so we add one if have
2997                 // AwaitingRemoteRevoke set, which indicates we sent a commitment_signed but haven't gotten
2998                 // the corresponding revoke_and_ack back yet.
2999                 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 };
3000
3001                 let resend_funding_locked = if msg.next_local_commitment_number == 1 && INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number == 1 {
3002                         // We should never have to worry about MonitorUpdateFailed resending FundingLocked
3003                         let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3004                         Some(msgs::FundingLocked {
3005                                 channel_id: self.channel_id(),
3006                                 next_per_commitment_point,
3007                         })
3008                 } else { None };
3009
3010                 if msg.next_local_commitment_number == next_counterparty_commitment_number {
3011                         if required_revoke.is_some() {
3012                                 log_debug!(logger, "Reconnected channel {} with only lost outbound RAA", log_bytes!(self.channel_id()));
3013                         } else {
3014                                 log_debug!(logger, "Reconnected channel {} with no loss", log_bytes!(self.channel_id()));
3015                         }
3016
3017                         if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateFailed as u32)) == 0 {
3018                                 // Note that if in the future we no longer drop holding cell update_adds on peer
3019                                 // disconnect, this logic will need to be updated.
3020                                 for htlc_update in self.holding_cell_htlc_updates.iter() {
3021                                         if let &HTLCUpdateAwaitingACK::AddHTLC { .. } = htlc_update {
3022                                                 debug_assert!(false, "There shouldn't be any add-HTLCs in the holding cell now because they should have been dropped on peer disconnect. Panic here because said HTLCs won't be handled correctly.");
3023                                         }
3024                                 }
3025
3026                                 // We're up-to-date and not waiting on a remote revoke (if we are our
3027                                 // channel_reestablish should result in them sending a revoke_and_ack), but we may
3028                                 // have received some updates while we were disconnected. Free the holding cell
3029                                 // now!
3030                                 match self.free_holding_cell_htlcs(logger) {
3031                                         Err(ChannelError::Close(msg)) => return Err(ChannelError::Close(msg)),
3032                                         Err(ChannelError::Ignore(_)) | Err(ChannelError::CloseDelayBroadcast(_)) => panic!("Got non-channel-failing result from free_holding_cell_htlcs"),
3033                                         Ok((Some((commitment_update, monitor_update)), htlcs_to_fail)) => {
3034                                                 // If in the future we no longer drop holding cell update_adds on peer
3035                                                 // disconnect, we may be handed some HTLCs to fail backwards here.
3036                                                 assert!(htlcs_to_fail.is_empty());
3037                                                 return Ok((resend_funding_locked, required_revoke, Some(commitment_update), Some(monitor_update), self.resend_order.clone(), shutdown_msg));
3038                                         },
3039                                         Ok((None, htlcs_to_fail)) => {
3040                                                 // If in the future we no longer drop holding cell update_adds on peer
3041                                                 // disconnect, we may be handed some HTLCs to fail backwards here.
3042                                                 assert!(htlcs_to_fail.is_empty());
3043                                                 return Ok((resend_funding_locked, required_revoke, None, None, self.resend_order.clone(), shutdown_msg));
3044                                         },
3045                                 }
3046                         } else {
3047                                 return Ok((resend_funding_locked, required_revoke, None, None, self.resend_order.clone(), shutdown_msg));
3048                         }
3049                 } else if msg.next_local_commitment_number == next_counterparty_commitment_number - 1 {
3050                         if required_revoke.is_some() {
3051                                 log_debug!(logger, "Reconnected channel {} with lost outbound RAA and lost remote commitment tx", log_bytes!(self.channel_id()));
3052                         } else {
3053                                 log_debug!(logger, "Reconnected channel {} with only lost remote commitment tx", log_bytes!(self.channel_id()));
3054                         }
3055
3056                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
3057                                 self.monitor_pending_commitment_signed = true;
3058                                 return Ok((resend_funding_locked, None, None, None, self.resend_order.clone(), shutdown_msg));
3059                         }
3060
3061                         return Ok((resend_funding_locked, required_revoke, Some(self.get_last_commitment_update(logger)), None, self.resend_order.clone(), shutdown_msg));
3062                 } else {
3063                         return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old remote commitment transaction".to_owned()));
3064                 }
3065         }
3066
3067         fn maybe_propose_first_closing_signed<F: Deref>(&mut self, fee_estimator: &F) -> Option<msgs::ClosingSigned>
3068                 where F::Target: FeeEstimator
3069         {
3070                 if !self.is_outbound() || !self.pending_inbound_htlcs.is_empty() || !self.pending_outbound_htlcs.is_empty() ||
3071                                 self.channel_state & (BOTH_SIDES_SHUTDOWN_MASK | ChannelState::AwaitingRemoteRevoke as u32) != BOTH_SIDES_SHUTDOWN_MASK ||
3072                                 self.last_sent_closing_fee.is_some() || self.pending_update_fee.is_some() {
3073                         return None;
3074                 }
3075
3076                 let mut proposed_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
3077                 if self.feerate_per_kw > proposed_feerate {
3078                         proposed_feerate = self.feerate_per_kw;
3079                 }
3080                 let tx_weight = self.get_closing_transaction_weight(Some(&self.get_closing_scriptpubkey()), Some(self.counterparty_shutdown_scriptpubkey.as_ref().unwrap()));
3081                 let proposed_total_fee_satoshis = proposed_feerate as u64 * tx_weight / 1000;
3082
3083                 let (closing_tx, total_fee_satoshis) = self.build_closing_transaction(proposed_total_fee_satoshis, false);
3084                 let sig = self.holder_signer
3085                         .sign_closing_transaction(&closing_tx, &self.secp_ctx)
3086                         .ok();
3087                 assert!(closing_tx.get_weight() as u64 <= tx_weight);
3088                 if sig.is_none() { return None; }
3089
3090                 self.last_sent_closing_fee = Some((proposed_feerate, total_fee_satoshis, sig.clone().unwrap()));
3091                 Some(msgs::ClosingSigned {
3092                         channel_id: self.channel_id,
3093                         fee_satoshis: total_fee_satoshis,
3094                         signature: sig.unwrap(),
3095                 })
3096         }
3097
3098         pub fn shutdown<F: Deref>(&mut self, fee_estimator: &F, their_features: &InitFeatures, msg: &msgs::Shutdown) -> Result<(Option<msgs::Shutdown>, Option<msgs::ClosingSigned>, Vec<(HTLCSource, PaymentHash)>), ChannelError>
3099                 where F::Target: FeeEstimator
3100         {
3101                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
3102                         return Err(ChannelError::Close("Peer sent shutdown when we needed a channel_reestablish".to_owned()));
3103                 }
3104                 if self.channel_state < ChannelState::FundingSent as u32 {
3105                         // Spec says we should fail the connection, not the channel, but that's nonsense, there
3106                         // are plenty of reasons you may want to fail a channel pre-funding, and spec says you
3107                         // can do that via error message without getting a connection fail anyway...
3108                         return Err(ChannelError::Close("Peer sent shutdown pre-funding generation".to_owned()));
3109                 }
3110                 for htlc in self.pending_inbound_htlcs.iter() {
3111                         if let InboundHTLCState::RemoteAnnounced(_) = htlc.state {
3112                                 return Err(ChannelError::Close("Got shutdown with remote pending HTLCs".to_owned()));
3113                         }
3114                 }
3115                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
3116
3117                 if is_unsupported_shutdown_script(&their_features, &msg.scriptpubkey) {
3118                         return Err(ChannelError::Close(format!("Got a nonstandard scriptpubkey ({}) from remote peer", msg.scriptpubkey.to_bytes().to_hex())));
3119                 }
3120
3121                 if self.counterparty_shutdown_scriptpubkey.is_some() {
3122                         if Some(&msg.scriptpubkey) != self.counterparty_shutdown_scriptpubkey.as_ref() {
3123                                 return Err(ChannelError::Close(format!("Got shutdown request with a scriptpubkey ({}) which did not match their previous scriptpubkey.", msg.scriptpubkey.to_bytes().to_hex())));
3124                         }
3125                 } else {
3126                         self.counterparty_shutdown_scriptpubkey = Some(msg.scriptpubkey.clone());
3127                 }
3128
3129                 // From here on out, we may not fail!
3130
3131                 self.channel_state |= ChannelState::RemoteShutdownSent as u32;
3132                 self.update_time_counter += 1;
3133
3134                 // We can't send our shutdown until we've committed all of our pending HTLCs, but the
3135                 // remote side is unlikely to accept any new HTLCs, so we go ahead and "free" any holding
3136                 // cell HTLCs and return them to fail the payment.
3137                 self.holding_cell_update_fee = None;
3138                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
3139                 self.holding_cell_htlc_updates.retain(|htlc_update| {
3140                         match htlc_update {
3141                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
3142                                         dropped_outbound_htlcs.push((source.clone(), payment_hash.clone()));
3143                                         false
3144                                 },
3145                                 _ => true
3146                         }
3147                 });
3148                 // If we have any LocalAnnounced updates we'll probably just get back a update_fail_htlc
3149                 // immediately after the commitment dance, but we can send a Shutdown cause we won't send
3150                 // any further commitment updates after we set LocalShutdownSent.
3151
3152                 let shutdown = if (self.channel_state & ChannelState::LocalShutdownSent as u32) == ChannelState::LocalShutdownSent as u32 {
3153                         None
3154                 } else {
3155                         Some(msgs::Shutdown {
3156                                 channel_id: self.channel_id,
3157                                 scriptpubkey: self.get_closing_scriptpubkey(),
3158                         })
3159                 };
3160
3161                 self.channel_state |= ChannelState::LocalShutdownSent as u32;
3162                 self.update_time_counter += 1;
3163
3164                 Ok((shutdown, self.maybe_propose_first_closing_signed(fee_estimator), dropped_outbound_htlcs))
3165         }
3166
3167         fn build_signed_closing_transaction(&self, tx: &mut Transaction, counterparty_sig: &Signature, sig: &Signature) {
3168                 if tx.input.len() != 1 { panic!("Tried to sign closing transaction that had input count != 1!"); }
3169                 if tx.input[0].witness.len() != 0 { panic!("Tried to re-sign closing transaction"); }
3170                 if tx.output.len() > 2 { panic!("Tried to sign bogus closing transaction"); }
3171
3172                 tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
3173
3174                 let funding_key = self.get_holder_pubkeys().funding_pubkey.serialize();
3175                 let counterparty_funding_key = self.counterparty_funding_pubkey().serialize();
3176                 if funding_key[..] < counterparty_funding_key[..] {
3177                         tx.input[0].witness.push(sig.serialize_der().to_vec());
3178                         tx.input[0].witness.push(counterparty_sig.serialize_der().to_vec());
3179                 } else {
3180                         tx.input[0].witness.push(counterparty_sig.serialize_der().to_vec());
3181                         tx.input[0].witness.push(sig.serialize_der().to_vec());
3182                 }
3183                 tx.input[0].witness[1].push(SigHashType::All as u8);
3184                 tx.input[0].witness[2].push(SigHashType::All as u8);
3185
3186                 tx.input[0].witness.push(self.get_funding_redeemscript().into_bytes());
3187         }
3188
3189         pub fn closing_signed<F: Deref>(&mut self, fee_estimator: &F, msg: &msgs::ClosingSigned) -> Result<(Option<msgs::ClosingSigned>, Option<Transaction>), ChannelError>
3190                 where F::Target: FeeEstimator
3191         {
3192                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != BOTH_SIDES_SHUTDOWN_MASK {
3193                         return Err(ChannelError::Close("Remote end sent us a closing_signed before both sides provided a shutdown".to_owned()));
3194                 }
3195                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
3196                         return Err(ChannelError::Close("Peer sent closing_signed when we needed a channel_reestablish".to_owned()));
3197                 }
3198                 if !self.pending_inbound_htlcs.is_empty() || !self.pending_outbound_htlcs.is_empty() {
3199                         return Err(ChannelError::Close("Remote end sent us a closing_signed while there were still pending HTLCs".to_owned()));
3200                 }
3201                 if msg.fee_satoshis > 21_000_000 * 1_0000_0000 { //this is required to stop potential overflow in build_closing_transaction
3202                         return Err(ChannelError::Close("Remote tried to send us a closing tx with > 21 million BTC fee".to_owned()));
3203                 }
3204
3205                 let funding_redeemscript = self.get_funding_redeemscript();
3206                 let (mut closing_tx, used_total_fee) = self.build_closing_transaction(msg.fee_satoshis, false);
3207                 if used_total_fee != msg.fee_satoshis {
3208                         return Err(ChannelError::Close(format!("Remote sent us a closing_signed with a fee greater than the value they can claim. Fee in message: {}", msg.fee_satoshis)));
3209                 }
3210                 let mut sighash = hash_to_message!(&bip143::SigHashCache::new(&closing_tx).signature_hash(0, &funding_redeemscript, self.channel_value_satoshis, SigHashType::All)[..]);
3211
3212                 match self.secp_ctx.verify(&sighash, &msg.signature, &self.get_counterparty_pubkeys().funding_pubkey) {
3213                         Ok(_) => {},
3214                         Err(_e) => {
3215                                 // The remote end may have decided to revoke their output due to inconsistent dust
3216                                 // limits, so check for that case by re-checking the signature here.
3217                                 closing_tx = self.build_closing_transaction(msg.fee_satoshis, true).0;
3218                                 sighash = hash_to_message!(&bip143::SigHashCache::new(&closing_tx).signature_hash(0, &funding_redeemscript, self.channel_value_satoshis, SigHashType::All)[..]);
3219                                 secp_check!(self.secp_ctx.verify(&sighash, &msg.signature, self.counterparty_funding_pubkey()), "Invalid closing tx signature from peer".to_owned());
3220                         },
3221                 };
3222
3223                 let closing_tx_max_weight = self.get_closing_transaction_weight(
3224                         if let Some(oup) = closing_tx.output.get(0) { Some(&oup.script_pubkey) } else { None },
3225                         if let Some(oup) = closing_tx.output.get(1) { Some(&oup.script_pubkey) } else { None });
3226                 if let Some((_, last_fee, sig)) = self.last_sent_closing_fee {
3227                         if last_fee == msg.fee_satoshis {
3228                                 self.build_signed_closing_transaction(&mut closing_tx, &msg.signature, &sig);
3229                                 assert!(closing_tx.get_weight() as u64 <= closing_tx_max_weight);
3230                                 debug_assert!(closing_tx.get_weight() as u64 >= closing_tx_max_weight - 2);
3231                                 self.channel_state = ChannelState::ShutdownComplete as u32;
3232                                 self.update_time_counter += 1;
3233                                 return Ok((None, Some(closing_tx)));
3234                         }
3235                 }
3236
3237                 macro_rules! propose_new_feerate {
3238                         ($new_feerate: expr) => {
3239                                 let tx_weight = self.get_closing_transaction_weight(Some(&self.get_closing_scriptpubkey()), Some(self.counterparty_shutdown_scriptpubkey.as_ref().unwrap()));
3240                                 let (closing_tx, used_total_fee) = self.build_closing_transaction($new_feerate as u64 * tx_weight / 1000, false);
3241                                 let sig = self.holder_signer
3242                                         .sign_closing_transaction(&closing_tx, &self.secp_ctx)
3243                                         .map_err(|_| ChannelError::Close("External signer refused to sign closing transaction".to_owned()))?;
3244                                 assert!(closing_tx.get_weight() as u64 <= tx_weight);
3245                                 self.last_sent_closing_fee = Some(($new_feerate, used_total_fee, sig.clone()));
3246                                 return Ok((Some(msgs::ClosingSigned {
3247                                         channel_id: self.channel_id,
3248                                         fee_satoshis: used_total_fee,
3249                                         signature: sig,
3250                                 }), None))
3251                         }
3252                 }
3253
3254                 let mut min_feerate = 253;
3255                 if self.is_outbound() {
3256                         let max_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
3257                         if (msg.fee_satoshis as u64) > max_feerate as u64 * closing_tx_max_weight / 1000 {
3258                                 if let Some((last_feerate, _, _)) = self.last_sent_closing_fee {
3259                                         if max_feerate <= last_feerate {
3260                                                 return Err(ChannelError::Close(format!("Unable to come to consensus about closing feerate, remote wanted something higher ({}) than our Normal feerate ({})", last_feerate, max_feerate)));
3261                                         }
3262                                 }
3263                                 propose_new_feerate!(max_feerate);
3264                         }
3265                 } else {
3266                         min_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
3267                 }
3268                 if (msg.fee_satoshis as u64) < min_feerate as u64 * closing_tx_max_weight / 1000 {
3269                         if let Some((last_feerate, _, _)) = self.last_sent_closing_fee {
3270                                 if min_feerate >= last_feerate {
3271                                         return Err(ChannelError::Close(format!("Unable to come to consensus about closing feerate, remote wanted something lower ({}) than our Background feerate ({}).", last_feerate, min_feerate)));
3272                                 }
3273                         }
3274                         propose_new_feerate!(min_feerate);
3275                 }
3276
3277                 let sig = self.holder_signer
3278                         .sign_closing_transaction(&closing_tx, &self.secp_ctx)
3279                         .map_err(|_| ChannelError::Close("External signer refused to sign closing transaction".to_owned()))?;
3280                 self.build_signed_closing_transaction(&mut closing_tx, &msg.signature, &sig);
3281                 assert!(closing_tx.get_weight() as u64 <= closing_tx_max_weight);
3282                 debug_assert!(closing_tx.get_weight() as u64 >= closing_tx_max_weight - 2);
3283
3284                 self.channel_state = ChannelState::ShutdownComplete as u32;
3285                 self.update_time_counter += 1;
3286
3287                 Ok((Some(msgs::ClosingSigned {
3288                         channel_id: self.channel_id,
3289                         fee_satoshis: msg.fee_satoshis,
3290                         signature: sig,
3291                 }), Some(closing_tx)))
3292         }
3293
3294         // Public utilities:
3295
3296         pub fn channel_id(&self) -> [u8; 32] {
3297                 self.channel_id
3298         }
3299
3300         /// Gets the "user_id" value passed into the construction of this channel. It has no special
3301         /// meaning and exists only to allow users to have a persistent identifier of a channel.
3302         pub fn get_user_id(&self) -> u64 {
3303                 self.user_id
3304         }
3305
3306         /// Guaranteed to be Some after both FundingLocked messages have been exchanged (and, thus,
3307         /// is_usable() returns true).
3308         /// Allowed in any state (including after shutdown)
3309         pub fn get_short_channel_id(&self) -> Option<u64> {
3310                 self.short_channel_id
3311         }
3312
3313         /// Returns the funding_txo we either got from our peer, or were given by
3314         /// get_outbound_funding_created.
3315         pub fn get_funding_txo(&self) -> Option<OutPoint> {
3316                 self.channel_transaction_parameters.funding_outpoint
3317         }
3318
3319         fn get_holder_selected_contest_delay(&self) -> u16 {
3320                 self.channel_transaction_parameters.holder_selected_contest_delay
3321         }
3322
3323         fn get_holder_pubkeys(&self) -> &ChannelPublicKeys {
3324                 &self.channel_transaction_parameters.holder_pubkeys
3325         }
3326
3327         fn get_counterparty_selected_contest_delay(&self) -> u16 {
3328                 self.channel_transaction_parameters.counterparty_parameters.as_ref().unwrap().selected_contest_delay
3329         }
3330
3331         fn get_counterparty_pubkeys(&self) -> &ChannelPublicKeys {
3332                 &self.channel_transaction_parameters.counterparty_parameters.as_ref().unwrap().pubkeys
3333         }
3334
3335         /// Allowed in any state (including after shutdown)
3336         pub fn get_counterparty_node_id(&self) -> PublicKey {
3337                 self.counterparty_node_id
3338         }
3339
3340         /// Allowed in any state (including after shutdown)
3341         #[cfg(test)]
3342         pub fn get_holder_htlc_minimum_msat(&self) -> u64 {
3343                 self.holder_htlc_minimum_msat
3344         }
3345
3346         /// Allowed in any state (including after shutdown)
3347         pub fn get_announced_htlc_max_msat(&self) -> u64 {
3348                 return cmp::min(
3349                         // Upper bound by capacity. We make it a bit less than full capacity to prevent attempts
3350                         // to use full capacity. This is an effort to reduce routing failures, because in many cases
3351                         // channel might have been used to route very small values (either by honest users or as DoS).
3352                         self.channel_value_satoshis * 1000 * 9 / 10,
3353
3354                         Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis)
3355                 );
3356         }
3357
3358         /// Allowed in any state (including after shutdown)
3359         pub fn get_counterparty_htlc_minimum_msat(&self) -> u64 {
3360                 self.counterparty_htlc_minimum_msat
3361         }
3362
3363         pub fn get_value_satoshis(&self) -> u64 {
3364                 self.channel_value_satoshis
3365         }
3366
3367         pub fn get_fee_proportional_millionths(&self) -> u32 {
3368                 self.config.fee_proportional_millionths
3369         }
3370
3371         pub fn get_cltv_expiry_delta(&self) -> u16 {
3372                 cmp::max(self.config.cltv_expiry_delta, MIN_CLTV_EXPIRY_DELTA)
3373         }
3374
3375         #[cfg(test)]
3376         pub fn get_feerate(&self) -> u32 {
3377                 self.feerate_per_kw
3378         }
3379
3380         pub fn get_cur_holder_commitment_transaction_number(&self) -> u64 {
3381                 self.cur_holder_commitment_transaction_number + 1
3382         }
3383
3384         pub fn get_cur_counterparty_commitment_transaction_number(&self) -> u64 {
3385                 self.cur_counterparty_commitment_transaction_number + 1 - if self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32) != 0 { 1 } else { 0 }
3386         }
3387
3388         pub fn get_revoked_counterparty_commitment_transaction_number(&self) -> u64 {
3389                 self.cur_counterparty_commitment_transaction_number + 2
3390         }
3391
3392         #[cfg(test)]
3393         pub fn get_signer(&self) -> &Signer {
3394                 &self.holder_signer
3395         }
3396
3397         #[cfg(test)]
3398         pub fn get_value_stat(&self) -> ChannelValueStat {
3399                 ChannelValueStat {
3400                         value_to_self_msat: self.value_to_self_msat,
3401                         channel_value_msat: self.channel_value_satoshis * 1000,
3402                         channel_reserve_msat: self.counterparty_selected_channel_reserve_satoshis * 1000,
3403                         pending_outbound_htlcs_amount_msat: self.pending_outbound_htlcs.iter().map(|ref h| h.amount_msat).sum::<u64>(),
3404                         pending_inbound_htlcs_amount_msat: self.pending_inbound_htlcs.iter().map(|ref h| h.amount_msat).sum::<u64>(),
3405                         holding_cell_outbound_amount_msat: {
3406                                 let mut res = 0;
3407                                 for h in self.holding_cell_htlc_updates.iter() {
3408                                         match h {
3409                                                 &HTLCUpdateAwaitingACK::AddHTLC{amount_msat, .. } => {
3410                                                         res += amount_msat;
3411                                                 }
3412                                                 _ => {}
3413                                         }
3414                                 }
3415                                 res
3416                         },
3417                         counterparty_max_htlc_value_in_flight_msat: self.counterparty_max_htlc_value_in_flight_msat,
3418                         counterparty_dust_limit_msat: self.counterparty_dust_limit_satoshis * 1000,
3419                 }
3420         }
3421
3422         /// Allowed in any state (including after shutdown)
3423         pub fn get_update_time_counter(&self) -> u32 {
3424                 self.update_time_counter
3425         }
3426
3427         pub fn get_latest_monitor_update_id(&self) -> u64 {
3428                 self.latest_monitor_update_id
3429         }
3430
3431         pub fn should_announce(&self) -> bool {
3432                 self.config.announced_channel
3433         }
3434
3435         pub fn is_outbound(&self) -> bool {
3436                 self.channel_transaction_parameters.is_outbound_from_holder
3437         }
3438
3439         /// Gets the fee we'd want to charge for adding an HTLC output to this Channel
3440         /// Allowed in any state (including after shutdown)
3441         pub fn get_holder_fee_base_msat<F: Deref>(&self, fee_estimator: &F) -> u32
3442                 where F::Target: FeeEstimator
3443         {
3444                 // For lack of a better metric, we calculate what it would cost to consolidate the new HTLC
3445                 // output value back into a transaction with the regular channel output:
3446
3447                 // the fee cost of the HTLC-Success/HTLC-Timeout transaction:
3448                 let mut res = self.feerate_per_kw as u64 * cmp::max(HTLC_TIMEOUT_TX_WEIGHT, HTLC_SUCCESS_TX_WEIGHT) / 1000;
3449
3450                 if self.is_outbound() {
3451                         // + the marginal fee increase cost to us in the commitment transaction:
3452                         res += self.feerate_per_kw as u64 * COMMITMENT_TX_WEIGHT_PER_HTLC / 1000;
3453                 }
3454
3455                 // + the marginal cost of an input which spends the HTLC-Success/HTLC-Timeout output:
3456                 res += fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal) as u64 * SPENDING_INPUT_FOR_A_OUTPUT_WEIGHT / 1000;
3457
3458                 res as u32
3459         }
3460
3461         /// Returns true if we've ever received a message from the remote end for this Channel
3462         pub fn have_received_message(&self) -> bool {
3463                 self.channel_state > (ChannelState::OurInitSent as u32)
3464         }
3465
3466         /// Returns true if this channel is fully established and not known to be closing.
3467         /// Allowed in any state (including after shutdown)
3468         pub fn is_usable(&self) -> bool {
3469                 let mask = ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK;
3470                 (self.channel_state & mask) == (ChannelState::ChannelFunded as u32)
3471         }
3472
3473         /// Returns true if this channel is currently available for use. This is a superset of
3474         /// is_usable() and considers things like the channel being temporarily disabled.
3475         /// Allowed in any state (including after shutdown)
3476         pub fn is_live(&self) -> bool {
3477                 self.is_usable() && (self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32) == 0)
3478         }
3479
3480         /// Returns true if this channel has been marked as awaiting a monitor update to move forward.
3481         /// Allowed in any state (including after shutdown)
3482         pub fn is_awaiting_monitor_update(&self) -> bool {
3483                 (self.channel_state & ChannelState::MonitorUpdateFailed as u32) != 0
3484         }
3485
3486         /// Returns true if funding_created was sent/received.
3487         pub fn is_funding_initiated(&self) -> bool {
3488                 self.channel_state >= ChannelState::FundingSent as u32
3489         }
3490
3491         /// Returns true if this channel is fully shut down. True here implies that no further actions
3492         /// may/will be taken on this channel, and thus this object should be freed. Any future changes
3493         /// will be handled appropriately by the chain monitor.
3494         pub fn is_shutdown(&self) -> bool {
3495                 if (self.channel_state & ChannelState::ShutdownComplete as u32) == ChannelState::ShutdownComplete as u32  {
3496                         assert!(self.channel_state == ChannelState::ShutdownComplete as u32);
3497                         true
3498                 } else { false }
3499         }
3500
3501         pub fn channel_update_status(&self) -> ChannelUpdateStatus {
3502                 self.channel_update_status
3503         }
3504
3505         pub fn set_channel_update_status(&mut self, status: ChannelUpdateStatus) {
3506                 self.channel_update_status = status;
3507         }
3508
3509         fn check_get_funding_locked(&mut self, height: u32) -> Option<msgs::FundingLocked> {
3510                 if self.funding_tx_confirmation_height == 0 {
3511                         return None;
3512                 }
3513
3514                 let funding_tx_confirmations = height as i64 - self.funding_tx_confirmation_height as i64 + 1;
3515                 if funding_tx_confirmations <= 0 {
3516                         self.funding_tx_confirmation_height = 0;
3517                 }
3518
3519                 if funding_tx_confirmations < self.minimum_depth as i64 {
3520                         return None;
3521                 }
3522
3523                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
3524                 let need_commitment_update = if non_shutdown_state == ChannelState::FundingSent as u32 {
3525                         self.channel_state |= ChannelState::OurFundingLocked as u32;
3526                         true
3527                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32) {
3528                         self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
3529                         self.update_time_counter += 1;
3530                         true
3531                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) {
3532                         // We got a reorg but not enough to trigger a force close, just ignore.
3533                         false
3534                 } else if self.channel_state < ChannelState::ChannelFunded as u32 {
3535                         panic!("Started confirming a channel in a state pre-FundingSent?: {}", self.channel_state);
3536                 } else {
3537                         // We got a reorg but not enough to trigger a force close, just ignore.
3538                         false
3539                 };
3540
3541                 if need_commitment_update {
3542                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) == 0 {
3543                                 let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3544                                 return Some(msgs::FundingLocked {
3545                                         channel_id: self.channel_id,
3546                                         next_per_commitment_point,
3547                                 });
3548                         } else {
3549                                 self.monitor_pending_funding_locked = true;
3550                         }
3551                 }
3552                 None
3553         }
3554
3555         /// When a transaction is confirmed, we check whether it is or spends the funding transaction
3556         /// In the first case, we store the confirmation height and calculating the short channel id.
3557         /// In the second, we simply return an Err indicating we need to be force-closed now.
3558         pub fn transactions_confirmed<L: Deref>(&mut self, block_hash: &BlockHash, height: u32, txdata: &TransactionData, logger: &L)
3559                         -> Result<Option<msgs::FundingLocked>, msgs::ErrorMessage> where L::Target: Logger {
3560                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
3561                 for &(index_in_block, tx) in txdata.iter() {
3562                         if let Some(funding_txo) = self.get_funding_txo() {
3563                                 // If we haven't yet sent a funding_locked, but are in FundingSent (ignoring
3564                                 // whether they've sent a funding_locked or not), check if we should send one.
3565                                 if non_shutdown_state & !(ChannelState::TheirFundingLocked as u32) == ChannelState::FundingSent as u32 {
3566                                         if tx.txid() == funding_txo.txid {
3567                                                 let txo_idx = funding_txo.index as usize;
3568                                                 if txo_idx >= tx.output.len() || tx.output[txo_idx].script_pubkey != self.get_funding_redeemscript().to_v0_p2wsh() ||
3569                                                                 tx.output[txo_idx].value != self.channel_value_satoshis {
3570                                                         if self.is_outbound() {
3571                                                                 // If we generated the funding transaction and it doesn't match what it
3572                                                                 // should, the client is really broken and we should just panic and
3573                                                                 // tell them off. That said, because hash collisions happen with high
3574                                                                 // probability in fuzztarget mode, if we're fuzzing we just close the
3575                                                                 // channel and move on.
3576                                                                 #[cfg(not(feature = "fuzztarget"))]
3577                                                                 panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
3578                                                         }
3579                                                         self.update_time_counter += 1;
3580                                                         return Err(msgs::ErrorMessage {
3581                                                                 channel_id: self.channel_id(),
3582                                                                 data: "funding tx had wrong script/value or output index".to_owned()
3583                                                         });
3584                                                 } else {
3585                                                         if self.is_outbound() {
3586                                                                 for input in tx.input.iter() {
3587                                                                         if input.witness.is_empty() {
3588                                                                                 // We generated a malleable funding transaction, implying we've
3589                                                                                 // just exposed ourselves to funds loss to our counterparty.
3590                                                                                 #[cfg(not(feature = "fuzztarget"))]
3591                                                                                 panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
3592                                                                         }
3593                                                                 }
3594                                                         }
3595                                                         self.funding_tx_confirmation_height = height;
3596                                                         self.funding_tx_confirmed_in = Some(*block_hash);
3597                                                         self.short_channel_id = match scid_from_parts(height as u64, index_in_block as u64, txo_idx as u64) {
3598                                                                 Ok(scid) => Some(scid),
3599                                                                 Err(_) => panic!("Block was bogus - either height was > 16 million, had > 16 million transactions, or had > 65k outputs"),
3600                                                         }
3601                                                 }
3602                                         }
3603                                         // If we allow 1-conf funding, we may need to check for funding_locked here and
3604                                         // send it immediately instead of waiting for a best_block_updated call (which
3605                                         // may have already happened for this block).
3606                                         if let Some(funding_locked) = self.check_get_funding_locked(height) {
3607                                                 return Ok(Some(funding_locked));
3608                                         }
3609                                 }
3610                                 for inp in tx.input.iter() {
3611                                         if inp.previous_output == funding_txo.into_bitcoin_outpoint() {
3612                                                 log_trace!(logger, "Detected channel-closing tx {} spending {}:{}, closing channel {}", tx.txid(), inp.previous_output.txid, inp.previous_output.vout, log_bytes!(self.channel_id()));
3613                                                 return Err(msgs::ErrorMessage {
3614                                                         channel_id: self.channel_id(),
3615                                                         data: "Commitment or closing transaction was confirmed on chain.".to_owned()
3616                                                 });
3617                                         }
3618                                 }
3619                         }
3620                 }
3621                 Ok(None)
3622         }
3623
3624         /// When a new block is connected, we check the height of the block against outbound holding
3625         /// cell HTLCs in case we need to give up on them prematurely and time them out. Everything
3626         /// else (e.g. commitment transaction broadcasts, HTLC transaction broadcasting, etc) is
3627         /// handled by the ChannelMonitor.
3628         ///
3629         /// If we return Err, the channel may have been closed, at which point the standard
3630         /// requirements apply - no calls may be made except those explicitly stated to be allowed
3631         /// post-shutdown.
3632         ///
3633         /// May return some HTLCs (and their payment_hash) which have timed out and should be failed
3634         /// back.
3635         pub fn best_block_updated(&mut self, height: u32, highest_header_time: u32) -> Result<(Option<msgs::FundingLocked>, Vec<(HTLCSource, PaymentHash)>), msgs::ErrorMessage> {
3636                 let mut timed_out_htlcs = Vec::new();
3637                 let unforwarded_htlc_cltv_limit = height + HTLC_FAIL_BACK_BUFFER;
3638                 self.holding_cell_htlc_updates.retain(|htlc_update| {
3639                         match htlc_update {
3640                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, ref cltv_expiry, .. } => {
3641                                         if *cltv_expiry <= unforwarded_htlc_cltv_limit {
3642                                                 timed_out_htlcs.push((source.clone(), payment_hash.clone()));
3643                                                 false
3644                                         } else { true }
3645                                 },
3646                                 _ => true
3647                         }
3648                 });
3649
3650                 self.update_time_counter = cmp::max(self.update_time_counter, highest_header_time);
3651
3652                 if let Some(funding_locked) = self.check_get_funding_locked(height) {
3653                         return Ok((Some(funding_locked), timed_out_htlcs));
3654                 }
3655
3656                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
3657                 if non_shutdown_state >= ChannelState::ChannelFunded as u32 ||
3658                    (non_shutdown_state & ChannelState::OurFundingLocked as u32) == ChannelState::OurFundingLocked as u32 {
3659                         let mut funding_tx_confirmations = height as i64 - self.funding_tx_confirmation_height as i64 + 1;
3660                         if self.funding_tx_confirmation_height == 0 {
3661                                 // Note that check_get_funding_locked may reset funding_tx_confirmation_height to
3662                                 // zero if it has been reorged out, however in either case, our state flags
3663                                 // indicate we've already sent a funding_locked
3664                                 funding_tx_confirmations = 0;
3665                         }
3666
3667                         // If we've sent funding_locked (or have both sent and received funding_locked), and
3668                         // the funding transaction's confirmation count has dipped below minimum_depth / 2,
3669                         // close the channel and hope we can get the latest state on chain (because presumably
3670                         // the funding transaction is at least still in the mempool of most nodes).
3671                         if funding_tx_confirmations < self.minimum_depth as i64 / 2 {
3672                                 return Err(msgs::ErrorMessage {
3673                                         channel_id: self.channel_id(),
3674                                         data: format!("Funding transaction was un-confirmed. Locked at {} confs, now have {} confs.", self.minimum_depth, funding_tx_confirmations),
3675                                 });
3676                         }
3677                 }
3678
3679                 Ok((None, timed_out_htlcs))
3680         }
3681
3682         /// Indicates the funding transaction is no longer confirmed in the main chain. This may
3683         /// force-close the channel, but may also indicate a harmless reorganization of a block or two
3684         /// before the channel has reached funding_locked and we can just wait for more blocks.
3685         pub fn funding_transaction_unconfirmed(&mut self) -> Result<(), msgs::ErrorMessage> {
3686                 if self.funding_tx_confirmation_height != 0 {
3687                         // We handle the funding disconnection by calling best_block_updated with a height one
3688                         // below where our funding was connected, implying a reorg back to conf_height - 1.
3689                         let reorg_height = self.funding_tx_confirmation_height - 1;
3690                         // We use the time field to bump the current time we set on channel updates if its
3691                         // larger. If we don't know that time has moved forward, we can just set it to the last
3692                         // time we saw and it will be ignored.
3693                         let best_time = self.update_time_counter;
3694                         match self.best_block_updated(reorg_height, best_time) {
3695                                 Ok((funding_locked, timed_out_htlcs)) => {
3696                                         assert!(funding_locked.is_none(), "We can't generate a funding with 0 confirmations?");
3697                                         assert!(timed_out_htlcs.is_empty(), "We can't have accepted HTLCs with a timeout before our funding confirmation?");
3698                                         Ok(())
3699                                 },
3700                                 Err(e) => Err(e)
3701                         }
3702                 } else {
3703                         // We never learned about the funding confirmation anyway, just ignore
3704                         Ok(())
3705                 }
3706         }
3707
3708         // Methods to get unprompted messages to send to the remote end (or where we already returned
3709         // something in the handler for the message that prompted this message):
3710
3711         pub fn get_open_channel(&self, chain_hash: BlockHash) -> msgs::OpenChannel {
3712                 if !self.is_outbound() {
3713                         panic!("Tried to open a channel for an inbound channel?");
3714                 }
3715                 if self.channel_state != ChannelState::OurInitSent as u32 {
3716                         panic!("Cannot generate an open_channel after we've moved forward");
3717                 }
3718
3719                 if self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
3720                         panic!("Tried to send an open_channel for a channel that has already advanced");
3721                 }
3722
3723                 let first_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3724                 let keys = self.get_holder_pubkeys();
3725
3726                 msgs::OpenChannel {
3727                         chain_hash,
3728                         temporary_channel_id: self.channel_id,
3729                         funding_satoshis: self.channel_value_satoshis,
3730                         push_msat: self.channel_value_satoshis * 1000 - self.value_to_self_msat,
3731                         dust_limit_satoshis: self.holder_dust_limit_satoshis,
3732                         max_htlc_value_in_flight_msat: Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis),
3733                         channel_reserve_satoshis: Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis),
3734                         htlc_minimum_msat: self.holder_htlc_minimum_msat,
3735                         feerate_per_kw: self.feerate_per_kw as u32,
3736                         to_self_delay: self.get_holder_selected_contest_delay(),
3737                         max_accepted_htlcs: OUR_MAX_HTLCS,
3738                         funding_pubkey: keys.funding_pubkey,
3739                         revocation_basepoint: keys.revocation_basepoint,
3740                         payment_point: keys.payment_point,
3741                         delayed_payment_basepoint: keys.delayed_payment_basepoint,
3742                         htlc_basepoint: keys.htlc_basepoint,
3743                         first_per_commitment_point,
3744                         channel_flags: if self.config.announced_channel {1} else {0},
3745                         shutdown_scriptpubkey: OptionalField::Present(if self.config.commit_upfront_shutdown_pubkey { self.get_closing_scriptpubkey() } else { Builder::new().into_script() })
3746                 }
3747         }
3748
3749         pub fn get_accept_channel(&self) -> msgs::AcceptChannel {
3750                 if self.is_outbound() {
3751                         panic!("Tried to send accept_channel for an outbound channel?");
3752                 }
3753                 if self.channel_state != (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32) {
3754                         panic!("Tried to send accept_channel after channel had moved forward");
3755                 }
3756                 if self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
3757                         panic!("Tried to send an accept_channel for a channel that has already advanced");
3758                 }
3759
3760                 let first_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3761                 let keys = self.get_holder_pubkeys();
3762
3763                 msgs::AcceptChannel {
3764                         temporary_channel_id: self.channel_id,
3765                         dust_limit_satoshis: self.holder_dust_limit_satoshis,
3766                         max_htlc_value_in_flight_msat: Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis),
3767                         channel_reserve_satoshis: Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis),
3768                         htlc_minimum_msat: self.holder_htlc_minimum_msat,
3769                         minimum_depth: self.minimum_depth,
3770                         to_self_delay: self.get_holder_selected_contest_delay(),
3771                         max_accepted_htlcs: OUR_MAX_HTLCS,
3772                         funding_pubkey: keys.funding_pubkey,
3773                         revocation_basepoint: keys.revocation_basepoint,
3774                         payment_point: keys.payment_point,
3775                         delayed_payment_basepoint: keys.delayed_payment_basepoint,
3776                         htlc_basepoint: keys.htlc_basepoint,
3777                         first_per_commitment_point,
3778                         shutdown_scriptpubkey: OptionalField::Present(if self.config.commit_upfront_shutdown_pubkey { self.get_closing_scriptpubkey() } else { Builder::new().into_script() })
3779                 }
3780         }
3781
3782         /// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
3783         fn get_outbound_funding_created_signature<L: Deref>(&mut self, logger: &L) -> Result<Signature, ChannelError> where L::Target: Logger {
3784                 let counterparty_keys = self.build_remote_transaction_keys()?;
3785                 let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, self.feerate_per_kw, logger).0;
3786                 Ok(self.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, &self.secp_ctx)
3787                                 .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0)
3788         }
3789
3790         /// Updates channel state with knowledge of the funding transaction's txid/index, and generates
3791         /// a funding_created message for the remote peer.
3792         /// Panics if called at some time other than immediately after initial handshake, if called twice,
3793         /// or if called on an inbound channel.
3794         /// Note that channel_id changes during this call!
3795         /// Do NOT broadcast the funding transaction until after a successful funding_signed call!
3796         /// If an Err is returned, it is a ChannelError::Close.
3797         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 {
3798                 if !self.is_outbound() {
3799                         panic!("Tried to create outbound funding_created message on an inbound channel!");
3800                 }
3801                 if self.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
3802                         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)");
3803                 }
3804                 if self.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
3805                                 self.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
3806                                 self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
3807                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
3808                 }
3809
3810                 self.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
3811                 self.holder_signer.ready_channel(&self.channel_transaction_parameters);
3812
3813                 let signature = match self.get_outbound_funding_created_signature(logger) {
3814                         Ok(res) => res,
3815                         Err(e) => {
3816                                 log_error!(logger, "Got bad signatures: {:?}!", e);
3817                                 self.channel_transaction_parameters.funding_outpoint = None;
3818                                 return Err(e);
3819                         }
3820                 };
3821
3822                 let temporary_channel_id = self.channel_id;
3823
3824                 // Now that we're past error-generating stuff, update our local state:
3825
3826                 self.channel_state = ChannelState::FundingCreated as u32;
3827                 self.channel_id = funding_txo.to_channel_id();
3828                 self.funding_transaction = Some(funding_transaction);
3829
3830                 Ok(msgs::FundingCreated {
3831                         temporary_channel_id,
3832                         funding_txid: funding_txo.txid,
3833                         funding_output_index: funding_txo.index,
3834                         signature
3835                 })
3836         }
3837
3838         /// Gets an UnsignedChannelAnnouncement, as well as a signature covering it using our
3839         /// bitcoin_key, if available, for this channel. The channel must be publicly announceable and
3840         /// available for use (have exchanged FundingLocked messages in both directions). Should be used
3841         /// for both loose and in response to an AnnouncementSignatures message from the remote peer.
3842         /// Will only fail if we're not in a state where channel_announcement may be sent (including
3843         /// closing).
3844         /// Note that the "channel must be funded" requirement is stricter than BOLT 7 requires - see
3845         /// https://github.com/lightningnetwork/lightning-rfc/issues/468
3846         pub fn get_channel_announcement(&self, node_id: PublicKey, chain_hash: BlockHash) -> Result<(msgs::UnsignedChannelAnnouncement, Signature), ChannelError> {
3847                 if !self.config.announced_channel {
3848                         return Err(ChannelError::Ignore("Channel is not available for public announcements".to_owned()));
3849                 }
3850                 if self.channel_state & (ChannelState::ChannelFunded as u32) == 0 {
3851                         return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement until the channel funding has been locked".to_owned()));
3852                 }
3853                 if (self.channel_state & (ChannelState::LocalShutdownSent as u32 | ChannelState::ShutdownComplete as u32)) != 0 {
3854                         return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement once the channel is closing".to_owned()));
3855                 }
3856
3857                 let were_node_one = node_id.serialize()[..] < self.counterparty_node_id.serialize()[..];
3858
3859                 let msg = msgs::UnsignedChannelAnnouncement {
3860                         features: ChannelFeatures::known(),
3861                         chain_hash,
3862                         short_channel_id: self.get_short_channel_id().unwrap(),
3863                         node_id_1: if were_node_one { node_id } else { self.get_counterparty_node_id() },
3864                         node_id_2: if were_node_one { self.get_counterparty_node_id() } else { node_id },
3865                         bitcoin_key_1: if were_node_one { self.get_holder_pubkeys().funding_pubkey } else { self.counterparty_funding_pubkey().clone() },
3866                         bitcoin_key_2: if were_node_one { self.counterparty_funding_pubkey().clone() } else { self.get_holder_pubkeys().funding_pubkey },
3867                         excess_data: Vec::new(),
3868                 };
3869
3870                 let sig = self.holder_signer.sign_channel_announcement(&msg, &self.secp_ctx)
3871                         .map_err(|_| ChannelError::Ignore("Signer rejected channel_announcement".to_owned()))?;
3872
3873                 Ok((msg, sig))
3874         }
3875
3876         /// May panic if called on a channel that wasn't immediately-previously
3877         /// self.remove_uncommitted_htlcs_and_mark_paused()'d
3878         pub fn get_channel_reestablish<L: Deref>(&self, logger: &L) -> msgs::ChannelReestablish where L::Target: Logger {
3879                 assert_eq!(self.channel_state & ChannelState::PeerDisconnected as u32, ChannelState::PeerDisconnected as u32);
3880                 assert_ne!(self.cur_counterparty_commitment_transaction_number, INITIAL_COMMITMENT_NUMBER);
3881                 // Prior to static_remotekey, my_current_per_commitment_point was critical to claiming
3882                 // current to_remote balances. However, it no longer has any use, and thus is now simply
3883                 // set to a dummy (but valid, as required by the spec) public key.
3884                 // fuzztarget mode marks a subset of pubkeys as invalid so that we can hit "invalid pubkey"
3885                 // branches, but we unwrap it below, so we arbitrarily select a dummy pubkey which is both
3886                 // valid, and valid in fuzztarget mode's arbitrary validity criteria:
3887                 let mut pk = [2; 33]; pk[1] = 0xff;
3888                 let dummy_pubkey = PublicKey::from_slice(&pk).unwrap();
3889                 let data_loss_protect = if self.cur_counterparty_commitment_transaction_number + 1 < INITIAL_COMMITMENT_NUMBER {
3890                         let remote_last_secret = self.commitment_secrets.get_secret(self.cur_counterparty_commitment_transaction_number + 2).unwrap();
3891                         log_trace!(logger, "Enough info to generate a Data Loss Protect with per_commitment_secret {}", log_bytes!(remote_last_secret));
3892                         OptionalField::Present(DataLossProtect {
3893                                 your_last_per_commitment_secret: remote_last_secret,
3894                                 my_current_per_commitment_point: dummy_pubkey
3895                         })
3896                 } else {
3897                         log_info!(logger, "Sending a data_loss_protect with no previous remote per_commitment_secret");
3898                         OptionalField::Present(DataLossProtect {
3899                                 your_last_per_commitment_secret: [0;32],
3900                                 my_current_per_commitment_point: dummy_pubkey,
3901                         })
3902                 };
3903                 msgs::ChannelReestablish {
3904                         channel_id: self.channel_id(),
3905                         // The protocol has two different commitment number concepts - the "commitment
3906                         // transaction number", which starts from 0 and counts up, and the "revocation key
3907                         // index" which starts at INITIAL_COMMITMENT_NUMBER and counts down. We track
3908                         // commitment transaction numbers by the index which will be used to reveal the
3909                         // revocation key for that commitment transaction, which means we have to convert them
3910                         // to protocol-level commitment numbers here...
3911
3912                         // next_local_commitment_number is the next commitment_signed number we expect to
3913                         // receive (indicating if they need to resend one that we missed).
3914                         next_local_commitment_number: INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number,
3915                         // We have to set next_remote_commitment_number to the next revoke_and_ack we expect to
3916                         // receive, however we track it by the next commitment number for a remote transaction
3917                         // (which is one further, as they always revoke previous commitment transaction, not
3918                         // the one we send) so we have to decrement by 1. Note that if
3919                         // cur_counterparty_commitment_transaction_number is INITIAL_COMMITMENT_NUMBER we will have
3920                         // dropped this channel on disconnect as it hasn't yet reached FundingSent so we can't
3921                         // overflow here.
3922                         next_remote_commitment_number: INITIAL_COMMITMENT_NUMBER - self.cur_counterparty_commitment_transaction_number - 1,
3923                         data_loss_protect,
3924                 }
3925         }
3926
3927
3928         // Send stuff to our remote peers:
3929
3930         /// Adds a pending outbound HTLC to this channel, note that you probably want
3931         /// send_htlc_and_commit instead cause you'll want both messages at once.
3932         /// This returns an option instead of a pure UpdateAddHTLC as we may be in a state where we are
3933         /// waiting on the remote peer to send us a revoke_and_ack during which time we cannot add new
3934         /// HTLCs on the wire or we wouldn't be able to determine what they actually ACK'ed.
3935         /// You MUST call send_commitment prior to any other calls on this Channel
3936         /// If an Err is returned, it's a ChannelError::Ignore!
3937         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> {
3938                 if (self.channel_state & (ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK)) != (ChannelState::ChannelFunded as u32) {
3939                         return Err(ChannelError::Ignore("Cannot send HTLC until channel is fully established and we haven't started shutting down".to_owned()));
3940                 }
3941                 let channel_total_msat = self.channel_value_satoshis * 1000;
3942                 if amount_msat > channel_total_msat {
3943                         return Err(ChannelError::Ignore(format!("Cannot send amount {}, because it is more than the total value of the channel {}", amount_msat, channel_total_msat)));
3944                 }
3945
3946                 if amount_msat == 0 {
3947                         return Err(ChannelError::Ignore("Cannot send 0-msat HTLC".to_owned()));
3948                 }
3949
3950                 if amount_msat < self.counterparty_htlc_minimum_msat {
3951                         return Err(ChannelError::Ignore(format!("Cannot send less than their minimum HTLC value ({})", self.counterparty_htlc_minimum_msat)));
3952                 }
3953
3954                 if (self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
3955                         // Note that this should never really happen, if we're !is_live() on receipt of an
3956                         // incoming HTLC for relay will result in us rejecting the HTLC and we won't allow
3957                         // the user to send directly into a !is_live() channel. However, if we
3958                         // disconnected during the time the previous hop was doing the commitment dance we may
3959                         // end up getting here after the forwarding delay. In any case, returning an
3960                         // IgnoreError will get ChannelManager to do the right thing and fail backwards now.
3961                         return Err(ChannelError::Ignore("Cannot send an HTLC while disconnected/frozen for channel monitor update".to_owned()));
3962                 }
3963
3964                 let (outbound_htlc_count, htlc_outbound_value_msat) = self.get_outbound_pending_htlc_stats();
3965                 if outbound_htlc_count + 1 > self.counterparty_max_accepted_htlcs as u32 {
3966                         return Err(ChannelError::Ignore(format!("Cannot push more than their max accepted HTLCs ({})", self.counterparty_max_accepted_htlcs)));
3967                 }
3968                 // Check their_max_htlc_value_in_flight_msat
3969                 if htlc_outbound_value_msat + amount_msat > self.counterparty_max_htlc_value_in_flight_msat {
3970                         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)));
3971                 }
3972
3973                 if !self.is_outbound() {
3974                         // Check that we won't violate the remote channel reserve by adding this HTLC.
3975                         let counterparty_balance_msat = self.channel_value_satoshis * 1000 - self.value_to_self_msat;
3976                         let holder_selected_chan_reserve_msat = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis);
3977                         let htlc_candidate = HTLCCandidate::new(amount_msat, HTLCInitiator::LocalOffered);
3978                         let counterparty_commit_tx_fee_msat = self.next_remote_commit_tx_fee_msat(htlc_candidate, None);
3979                         if counterparty_balance_msat < holder_selected_chan_reserve_msat + counterparty_commit_tx_fee_msat {
3980                                 return Err(ChannelError::Ignore("Cannot send value that would put counterparty balance under holder-announced channel reserve value".to_owned()));
3981                         }
3982                 }
3983
3984                 let pending_value_to_self_msat = self.value_to_self_msat - htlc_outbound_value_msat;
3985                 if pending_value_to_self_msat < amount_msat {
3986                         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)));
3987                 }
3988
3989                 // `2 *` and extra HTLC are for the fee spike buffer.
3990                 let commit_tx_fee_msat = if self.is_outbound() {
3991                         let htlc_candidate = HTLCCandidate::new(amount_msat, HTLCInitiator::LocalOffered);
3992                         2 * self.next_local_commit_tx_fee_msat(htlc_candidate, Some(()))
3993                 } else { 0 };
3994                 if pending_value_to_self_msat - amount_msat < commit_tx_fee_msat {
3995                         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)));
3996                 }
3997
3998                 // Check self.counterparty_selected_channel_reserve_satoshis (the amount we must keep as
3999                 // reserve for the remote to have something to claim if we misbehave)
4000                 let chan_reserve_msat = self.counterparty_selected_channel_reserve_satoshis * 1000;
4001                 if pending_value_to_self_msat - amount_msat - commit_tx_fee_msat < chan_reserve_msat {
4002                         return Err(ChannelError::Ignore(format!("Cannot send value that would put our balance under counterparty-announced channel reserve value ({})", chan_reserve_msat)));
4003                 }
4004
4005                 // Now update local state:
4006                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
4007                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::AddHTLC {
4008                                 amount_msat,
4009                                 payment_hash,
4010                                 cltv_expiry,
4011                                 source,
4012                                 onion_routing_packet,
4013                         });
4014                         return Ok(None);
4015                 }
4016
4017                 self.pending_outbound_htlcs.push(OutboundHTLCOutput {
4018                         htlc_id: self.next_holder_htlc_id,
4019                         amount_msat,
4020                         payment_hash: payment_hash.clone(),
4021                         cltv_expiry,
4022                         state: OutboundHTLCState::LocalAnnounced(Box::new(onion_routing_packet.clone())),
4023                         source,
4024                 });
4025
4026                 let res = msgs::UpdateAddHTLC {
4027                         channel_id: self.channel_id,
4028                         htlc_id: self.next_holder_htlc_id,
4029                         amount_msat,
4030                         payment_hash,
4031                         cltv_expiry,
4032                         onion_routing_packet,
4033                 };
4034                 self.next_holder_htlc_id += 1;
4035
4036                 Ok(Some(res))
4037         }
4038
4039         /// Creates a signed commitment transaction to send to the remote peer.
4040         /// Always returns a ChannelError::Close if an immediately-preceding (read: the
4041         /// last call to this Channel) send_htlc returned Ok(Some(_)) and there is an Err.
4042         /// May panic if called except immediately after a successful, Ok(Some(_))-returning send_htlc.
4043         pub fn send_commitment<L: Deref>(&mut self, logger: &L) -> Result<(msgs::CommitmentSigned, ChannelMonitorUpdate), ChannelError> where L::Target: Logger {
4044                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
4045                         panic!("Cannot create commitment tx until channel is fully established");
4046                 }
4047                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
4048                         panic!("Cannot create commitment tx until remote revokes their previous commitment");
4049                 }
4050                 if (self.channel_state & (ChannelState::PeerDisconnected as u32)) == (ChannelState::PeerDisconnected as u32) {
4051                         panic!("Cannot create commitment tx while disconnected, as send_htlc will have returned an Err so a send_commitment precondition has been violated");
4052                 }
4053                 if (self.channel_state & (ChannelState::MonitorUpdateFailed as u32)) == (ChannelState::MonitorUpdateFailed as u32) {
4054                         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");
4055                 }
4056                 let mut have_updates = self.pending_update_fee.is_some();
4057                 for htlc in self.pending_outbound_htlcs.iter() {
4058                         if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
4059                                 have_updates = true;
4060                         }
4061                         if have_updates { break; }
4062                 }
4063                 for htlc in self.pending_inbound_htlcs.iter() {
4064                         if let InboundHTLCState::LocalRemoved(_) = htlc.state {
4065                                 have_updates = true;
4066                         }
4067                         if have_updates { break; }
4068                 }
4069                 if !have_updates {
4070                         panic!("Cannot create commitment tx until we have some updates to send");
4071                 }
4072                 self.send_commitment_no_status_check(logger)
4073         }
4074         /// Only fails in case of bad keys
4075         fn send_commitment_no_status_check<L: Deref>(&mut self, logger: &L) -> Result<(msgs::CommitmentSigned, ChannelMonitorUpdate), ChannelError> where L::Target: Logger {
4076                 // We can upgrade the status of some HTLCs that are waiting on a commitment, even if we
4077                 // fail to generate this, we still are at least at a position where upgrading their status
4078                 // is acceptable.
4079                 for htlc in self.pending_inbound_htlcs.iter_mut() {
4080                         let new_state = if let &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(ref forward_info) = &htlc.state {
4081                                 Some(InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info.clone()))
4082                         } else { None };
4083                         if let Some(state) = new_state {
4084                                 htlc.state = state;
4085                         }
4086                 }
4087                 for htlc in self.pending_outbound_htlcs.iter_mut() {
4088                         if let Some(fail_reason) = if let &mut OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref mut fail_reason) = &mut htlc.state {
4089                                 Some(fail_reason.take())
4090                         } else { None } {
4091                                 htlc.state = OutboundHTLCState::AwaitingRemovedRemoteRevoke(fail_reason);
4092                         }
4093                 }
4094                 self.resend_order = RAACommitmentOrder::RevokeAndACKFirst;
4095
4096                 let (res, counterparty_commitment_txid, htlcs) = match self.send_commitment_no_state_update(logger) {
4097                         Ok((res, (counterparty_commitment_tx, mut htlcs))) => {
4098                                 // Update state now that we've passed all the can-fail calls...
4099                                 let htlcs_no_ref: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)> =
4100                                         htlcs.drain(..).map(|(htlc, htlc_source)| (htlc, htlc_source.map(|source_ref| Box::new(source_ref.clone())))).collect();
4101                                 (res, counterparty_commitment_tx, htlcs_no_ref)
4102                         },
4103                         Err(e) => return Err(e),
4104                 };
4105
4106                 self.latest_monitor_update_id += 1;
4107                 let monitor_update = ChannelMonitorUpdate {
4108                         update_id: self.latest_monitor_update_id,
4109                         updates: vec![ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo {
4110                                 commitment_txid: counterparty_commitment_txid,
4111                                 htlc_outputs: htlcs.clone(),
4112                                 commitment_number: self.cur_counterparty_commitment_transaction_number,
4113                                 their_revocation_point: self.counterparty_cur_commitment_point.unwrap()
4114                         }]
4115                 };
4116                 self.channel_state |= ChannelState::AwaitingRemoteRevoke as u32;
4117                 Ok((res, monitor_update))
4118         }
4119
4120         /// Only fails in case of bad keys. Used for channel_reestablish commitment_signed generation
4121         /// when we shouldn't change HTLC/channel state.
4122         fn send_commitment_no_state_update<L: Deref>(&self, logger: &L) -> Result<(msgs::CommitmentSigned, (Txid, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>)), ChannelError> where L::Target: Logger {
4123                 let mut feerate_per_kw = self.feerate_per_kw;
4124                 if let Some(feerate) = self.pending_update_fee {
4125                         if self.is_outbound() {
4126                                 feerate_per_kw = feerate;
4127                         }
4128                 }
4129
4130                 let counterparty_keys = self.build_remote_transaction_keys()?;
4131                 let counterparty_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, true, feerate_per_kw, logger);
4132                 let counterparty_commitment_txid = counterparty_commitment_tx.0.trust().txid();
4133                 let (signature, htlc_signatures);
4134
4135                 #[cfg(any(test, feature = "fuzztarget"))]
4136                 {
4137                         if !self.is_outbound() {
4138                                 let projected_commit_tx_info = self.next_remote_commitment_tx_fee_info_cached.lock().unwrap().take();
4139                                 *self.next_local_commitment_tx_fee_info_cached.lock().unwrap() = None;
4140                                 if let Some(info) = projected_commit_tx_info {
4141                                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len();
4142                                         if info.total_pending_htlcs == total_pending_htlcs
4143                                                 && info.next_holder_htlc_id == self.next_holder_htlc_id
4144                                                 && info.next_counterparty_htlc_id == self.next_counterparty_htlc_id
4145                                                 && info.feerate == self.feerate_per_kw {
4146                                                         let actual_fee = self.commit_tx_fee_msat(counterparty_commitment_tx.1);
4147                                                         assert_eq!(actual_fee, info.fee);
4148                                                 }
4149                                 }
4150                         }
4151                 }
4152
4153                 {
4154                         let mut htlcs = Vec::with_capacity(counterparty_commitment_tx.2.len());
4155                         for &(ref htlc, _) in counterparty_commitment_tx.2.iter() {
4156                                 htlcs.push(htlc);
4157                         }
4158
4159                         let res = self.holder_signer.sign_counterparty_commitment(&counterparty_commitment_tx.0, &self.secp_ctx)
4160                                 .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?;
4161                         signature = res.0;
4162                         htlc_signatures = res.1;
4163
4164                         log_trace!(logger, "Signed remote commitment tx {} (txid {}) with redeemscript {} -> {}",
4165                                 encode::serialize_hex(&counterparty_commitment_tx.0.trust().built_transaction().transaction),
4166                                 &counterparty_commitment_txid,
4167                                 encode::serialize_hex(&self.get_funding_redeemscript()),
4168                                 log_bytes!(signature.serialize_compact()[..]));
4169
4170                         for (ref htlc_sig, ref htlc) in htlc_signatures.iter().zip(htlcs) {
4171                                 log_trace!(logger, "Signed remote HTLC tx {} with redeemscript {} with pubkey {} -> {}",
4172                                         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)),
4173                                         encode::serialize_hex(&chan_utils::get_htlc_redeemscript(&htlc, &counterparty_keys)),
4174                                         log_bytes!(counterparty_keys.broadcaster_htlc_key.serialize()),
4175                                         log_bytes!(htlc_sig.serialize_compact()[..]));
4176                         }
4177                 }
4178
4179                 Ok((msgs::CommitmentSigned {
4180                         channel_id: self.channel_id,
4181                         signature,
4182                         htlc_signatures,
4183                 }, (counterparty_commitment_txid, counterparty_commitment_tx.2)))
4184         }
4185
4186         /// Adds a pending outbound HTLC to this channel, and creates a signed commitment transaction
4187         /// to send to the remote peer in one go.
4188         /// Shorthand for calling send_htlc() followed by send_commitment(), see docs on those for
4189         /// more info.
4190         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 {
4191                 match self.send_htlc(amount_msat, payment_hash, cltv_expiry, source, onion_routing_packet)? {
4192                         Some(update_add_htlc) => {
4193                                 let (commitment_signed, monitor_update) = self.send_commitment_no_status_check(logger)?;
4194                                 Ok(Some((update_add_htlc, commitment_signed, monitor_update)))
4195                         },
4196                         None => Ok(None)
4197                 }
4198         }
4199
4200         /// Get forwarding information for the counterparty.
4201         pub fn counterparty_forwarding_info(&self) -> Option<CounterpartyForwardingInfo> {
4202                 self.counterparty_forwarding_info.clone()
4203         }
4204
4205         pub fn channel_update(&mut self, msg: &msgs::ChannelUpdate) -> Result<(), ChannelError> {
4206                 let usable_channel_value_msat = (self.channel_value_satoshis - self.counterparty_selected_channel_reserve_satoshis) * 1000;
4207                 if msg.contents.htlc_minimum_msat >= usable_channel_value_msat {
4208                         return Err(ChannelError::Close("Minimum htlc value is greater than channel value".to_string()));
4209                 }
4210                 self.counterparty_forwarding_info = Some(CounterpartyForwardingInfo {
4211                         fee_base_msat: msg.contents.fee_base_msat,
4212                         fee_proportional_millionths: msg.contents.fee_proportional_millionths,
4213                         cltv_expiry_delta: msg.contents.cltv_expiry_delta
4214                 });
4215
4216                 Ok(())
4217         }
4218
4219         /// Begins the shutdown process, getting a message for the remote peer and returning all
4220         /// holding cell HTLCs for payment failure.
4221         pub fn get_shutdown(&mut self) -> Result<(msgs::Shutdown, Vec<(HTLCSource, PaymentHash)>), APIError> {
4222                 for htlc in self.pending_outbound_htlcs.iter() {
4223                         if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
4224                                 return Err(APIError::APIMisuseError{err: "Cannot begin shutdown with pending HTLCs. Process pending events first".to_owned()});
4225                         }
4226                 }
4227                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != 0 {
4228                         if (self.channel_state & ChannelState::LocalShutdownSent as u32) == ChannelState::LocalShutdownSent as u32 {
4229                                 return Err(APIError::APIMisuseError{err: "Shutdown already in progress".to_owned()});
4230                         }
4231                         else if (self.channel_state & ChannelState::RemoteShutdownSent as u32) == ChannelState::RemoteShutdownSent as u32 {
4232                                 return Err(APIError::ChannelUnavailable{err: "Shutdown already in progress by remote".to_owned()});
4233                         }
4234                 }
4235                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
4236                 if self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32) != 0 {
4237                         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()});
4238                 }
4239
4240                 let closing_script = self.get_closing_scriptpubkey();
4241
4242                 // From here on out, we may not fail!
4243                 if self.channel_state < ChannelState::FundingSent as u32 {
4244                         self.channel_state = ChannelState::ShutdownComplete as u32;
4245                 } else {
4246                         self.channel_state |= ChannelState::LocalShutdownSent as u32;
4247                 }
4248                 self.update_time_counter += 1;
4249
4250                 // Go ahead and drop holding cell updates as we'd rather fail payments than wait to send
4251                 // our shutdown until we've committed all of the pending changes.
4252                 self.holding_cell_update_fee = None;
4253                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
4254                 self.holding_cell_htlc_updates.retain(|htlc_update| {
4255                         match htlc_update {
4256                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
4257                                         dropped_outbound_htlcs.push((source.clone(), payment_hash.clone()));
4258                                         false
4259                                 },
4260                                 _ => true
4261                         }
4262                 });
4263
4264                 Ok((msgs::Shutdown {
4265                         channel_id: self.channel_id,
4266                         scriptpubkey: closing_script,
4267                 }, dropped_outbound_htlcs))
4268         }
4269
4270         /// Gets the latest commitment transaction and any dependent transactions for relay (forcing
4271         /// shutdown of this channel - no more calls into this Channel may be made afterwards except
4272         /// those explicitly stated to be allowed after shutdown completes, eg some simple getters).
4273         /// Also returns the list of payment_hashes for channels which we can safely fail backwards
4274         /// immediately (others we will have to allow to time out).
4275         pub fn force_shutdown(&mut self, should_broadcast: bool) -> (Option<(OutPoint, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>) {
4276                 // Note that we MUST only generate a monitor update that indicates force-closure - we're
4277                 // called during initialization prior to the chain_monitor in the encompassing ChannelManager
4278                 // being fully configured in some cases. Thus, its likely any monitor events we generate will
4279                 // be delayed in being processed! See the docs for `ChannelManagerReadArgs` for more.
4280                 assert!(self.channel_state != ChannelState::ShutdownComplete as u32);
4281
4282                 // We go ahead and "free" any holding cell HTLCs or HTLCs we haven't yet committed to and
4283                 // return them to fail the payment.
4284                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
4285                 for htlc_update in self.holding_cell_htlc_updates.drain(..) {
4286                         match htlc_update {
4287                                 HTLCUpdateAwaitingACK::AddHTLC { source, payment_hash, .. } => {
4288                                         dropped_outbound_htlcs.push((source, payment_hash));
4289                                 },
4290                                 _ => {}
4291                         }
4292                 }
4293                 let monitor_update = if let Some(funding_txo) = self.get_funding_txo() {
4294                         // If we haven't yet exchanged funding signatures (ie channel_state < FundingSent),
4295                         // returning a channel monitor update here would imply a channel monitor update before
4296                         // we even registered the channel monitor to begin with, which is invalid.
4297                         // Thus, if we aren't actually at a point where we could conceivably broadcast the
4298                         // funding transaction, don't return a funding txo (which prevents providing the
4299                         // monitor update to the user, even if we return one).
4300                         // See test_duplicate_chan_id and test_pre_lockin_no_chan_closed_update for more.
4301                         if self.channel_state & (ChannelState::FundingSent as u32 | ChannelState::ChannelFunded as u32 | ChannelState::ShutdownComplete as u32) != 0 {
4302                                 self.latest_monitor_update_id += 1;
4303                                 Some((funding_txo, ChannelMonitorUpdate {
4304                                         update_id: self.latest_monitor_update_id,
4305                                         updates: vec![ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast }],
4306                                 }))
4307                         } else { None }
4308                 } else { None };
4309
4310                 self.channel_state = ChannelState::ShutdownComplete as u32;
4311                 self.update_time_counter += 1;
4312                 (monitor_update, dropped_outbound_htlcs)
4313         }
4314 }
4315
4316 fn is_unsupported_shutdown_script(their_features: &InitFeatures, script: &Script) -> bool {
4317         // We restrain shutdown scripts to standards forms to avoid transactions not propagating on the p2p tx-relay network
4318
4319         // BOLT 2 says we must only send a scriptpubkey of certain standard forms,
4320         // which for a a BIP-141-compliant witness program is at max 42 bytes in length.
4321         // So don't let the remote peer feed us some super fee-heavy script.
4322         let is_script_too_long = script.len() > 42;
4323         if is_script_too_long {
4324                 return true;
4325         }
4326
4327         if their_features.supports_shutdown_anysegwit() && script.is_witness_program() && script.as_bytes()[0] != OP_PUSHBYTES_0.into_u8() {
4328                 return false;
4329         }
4330
4331         return !script.is_p2pkh() && !script.is_p2sh() && !script.is_v0_p2wpkh() && !script.is_v0_p2wsh()
4332 }
4333
4334 const SERIALIZATION_VERSION: u8 = 1;
4335 const MIN_SERIALIZATION_VERSION: u8 = 1;
4336
4337 impl Writeable for InboundHTLCRemovalReason {
4338         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
4339                 match self {
4340                         &InboundHTLCRemovalReason::FailRelay(ref error_packet) => {
4341                                 0u8.write(writer)?;
4342                                 error_packet.write(writer)?;
4343                         },
4344                         &InboundHTLCRemovalReason::FailMalformed((ref onion_hash, ref err_code)) => {
4345                                 1u8.write(writer)?;
4346                                 onion_hash.write(writer)?;
4347                                 err_code.write(writer)?;
4348                         },
4349                         &InboundHTLCRemovalReason::Fulfill(ref payment_preimage) => {
4350                                 2u8.write(writer)?;
4351                                 payment_preimage.write(writer)?;
4352                         },
4353                 }
4354                 Ok(())
4355         }
4356 }
4357
4358 impl Readable for InboundHTLCRemovalReason {
4359         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
4360                 Ok(match <u8 as Readable>::read(reader)? {
4361                         0 => InboundHTLCRemovalReason::FailRelay(Readable::read(reader)?),
4362                         1 => InboundHTLCRemovalReason::FailMalformed((Readable::read(reader)?, Readable::read(reader)?)),
4363                         2 => InboundHTLCRemovalReason::Fulfill(Readable::read(reader)?),
4364                         _ => return Err(DecodeError::InvalidValue),
4365                 })
4366         }
4367 }
4368
4369 impl Writeable for ChannelUpdateStatus {
4370         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
4371                 // We only care about writing out the current state as it was announced, ie only either
4372                 // Enabled or Disabled. In the case of DisabledStaged, we most recently announced the
4373                 // channel as enabled, so we write 0. For EnabledStaged, we similarly write a 1.
4374                 match self {
4375                         ChannelUpdateStatus::Enabled => 0u8.write(writer)?,
4376                         ChannelUpdateStatus::DisabledStaged => 0u8.write(writer)?,
4377                         ChannelUpdateStatus::EnabledStaged => 1u8.write(writer)?,
4378                         ChannelUpdateStatus::Disabled => 1u8.write(writer)?,
4379                 }
4380                 Ok(())
4381         }
4382 }
4383
4384 impl Readable for ChannelUpdateStatus {
4385         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
4386                 Ok(match <u8 as Readable>::read(reader)? {
4387                         0 => ChannelUpdateStatus::Enabled,
4388                         1 => ChannelUpdateStatus::Disabled,
4389                         _ => return Err(DecodeError::InvalidValue),
4390                 })
4391         }
4392 }
4393
4394 impl<Signer: Sign> Writeable for Channel<Signer> {
4395         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
4396                 // Note that we write out as if remove_uncommitted_htlcs_and_mark_paused had just been
4397                 // called but include holding cell updates (and obviously we don't modify self).
4398
4399                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
4400                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
4401
4402                 self.user_id.write(writer)?;
4403                 self.config.write(writer)?;
4404
4405                 self.channel_id.write(writer)?;
4406                 (self.channel_state | ChannelState::PeerDisconnected as u32).write(writer)?;
4407                 self.channel_value_satoshis.write(writer)?;
4408
4409                 self.latest_monitor_update_id.write(writer)?;
4410
4411                 let mut key_data = VecWriter(Vec::new());
4412                 self.holder_signer.write(&mut key_data)?;
4413                 assert!(key_data.0.len() < std::usize::MAX);
4414                 assert!(key_data.0.len() < std::u32::MAX as usize);
4415                 (key_data.0.len() as u32).write(writer)?;
4416                 writer.write_all(&key_data.0[..])?;
4417
4418                 self.shutdown_pubkey.write(writer)?;
4419                 self.destination_script.write(writer)?;
4420
4421                 self.cur_holder_commitment_transaction_number.write(writer)?;
4422                 self.cur_counterparty_commitment_transaction_number.write(writer)?;
4423                 self.value_to_self_msat.write(writer)?;
4424
4425                 let mut dropped_inbound_htlcs = 0;
4426                 for htlc in self.pending_inbound_htlcs.iter() {
4427                         if let InboundHTLCState::RemoteAnnounced(_) = htlc.state {
4428                                 dropped_inbound_htlcs += 1;
4429                         }
4430                 }
4431                 (self.pending_inbound_htlcs.len() as u64 - dropped_inbound_htlcs).write(writer)?;
4432                 for htlc in self.pending_inbound_htlcs.iter() {
4433                         if let &InboundHTLCState::RemoteAnnounced(_) = &htlc.state {
4434                                 continue; // Drop
4435                         }
4436                         htlc.htlc_id.write(writer)?;
4437                         htlc.amount_msat.write(writer)?;
4438                         htlc.cltv_expiry.write(writer)?;
4439                         htlc.payment_hash.write(writer)?;
4440                         match &htlc.state {
4441                                 &InboundHTLCState::RemoteAnnounced(_) => unreachable!(),
4442                                 &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(ref htlc_state) => {
4443                                         1u8.write(writer)?;
4444                                         htlc_state.write(writer)?;
4445                                 },
4446                                 &InboundHTLCState::AwaitingAnnouncedRemoteRevoke(ref htlc_state) => {
4447                                         2u8.write(writer)?;
4448                                         htlc_state.write(writer)?;
4449                                 },
4450                                 &InboundHTLCState::Committed => {
4451                                         3u8.write(writer)?;
4452                                 },
4453                                 &InboundHTLCState::LocalRemoved(ref removal_reason) => {
4454                                         4u8.write(writer)?;
4455                                         removal_reason.write(writer)?;
4456                                 },
4457                         }
4458                 }
4459
4460                 (self.pending_outbound_htlcs.len() as u64).write(writer)?;
4461                 for htlc in self.pending_outbound_htlcs.iter() {
4462                         htlc.htlc_id.write(writer)?;
4463                         htlc.amount_msat.write(writer)?;
4464                         htlc.cltv_expiry.write(writer)?;
4465                         htlc.payment_hash.write(writer)?;
4466                         htlc.source.write(writer)?;
4467                         match &htlc.state {
4468                                 &OutboundHTLCState::LocalAnnounced(ref onion_packet) => {
4469                                         0u8.write(writer)?;
4470                                         onion_packet.write(writer)?;
4471                                 },
4472                                 &OutboundHTLCState::Committed => {
4473                                         1u8.write(writer)?;
4474                                 },
4475                                 &OutboundHTLCState::RemoteRemoved(ref fail_reason) => {
4476                                         2u8.write(writer)?;
4477                                         fail_reason.write(writer)?;
4478                                 },
4479                                 &OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref fail_reason) => {
4480                                         3u8.write(writer)?;
4481                                         fail_reason.write(writer)?;
4482                                 },
4483                                 &OutboundHTLCState::AwaitingRemovedRemoteRevoke(ref fail_reason) => {
4484                                         4u8.write(writer)?;
4485                                         fail_reason.write(writer)?;
4486                                 },
4487                         }
4488                 }
4489
4490                 (self.holding_cell_htlc_updates.len() as u64).write(writer)?;
4491                 for update in self.holding_cell_htlc_updates.iter() {
4492                         match update {
4493                                 &HTLCUpdateAwaitingACK::AddHTLC { ref amount_msat, ref cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet } => {
4494                                         0u8.write(writer)?;
4495                                         amount_msat.write(writer)?;
4496                                         cltv_expiry.write(writer)?;
4497                                         payment_hash.write(writer)?;
4498                                         source.write(writer)?;
4499                                         onion_routing_packet.write(writer)?;
4500                                 },
4501                                 &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, ref htlc_id } => {
4502                                         1u8.write(writer)?;
4503                                         payment_preimage.write(writer)?;
4504                                         htlc_id.write(writer)?;
4505                                 },
4506                                 &HTLCUpdateAwaitingACK::FailHTLC { ref htlc_id, ref err_packet } => {
4507                                         2u8.write(writer)?;
4508                                         htlc_id.write(writer)?;
4509                                         err_packet.write(writer)?;
4510                                 }
4511                         }
4512                 }
4513
4514                 match self.resend_order {
4515                         RAACommitmentOrder::CommitmentFirst => 0u8.write(writer)?,
4516                         RAACommitmentOrder::RevokeAndACKFirst => 1u8.write(writer)?,
4517                 }
4518
4519                 self.monitor_pending_funding_locked.write(writer)?;
4520                 self.monitor_pending_revoke_and_ack.write(writer)?;
4521                 self.monitor_pending_commitment_signed.write(writer)?;
4522
4523                 (self.monitor_pending_forwards.len() as u64).write(writer)?;
4524                 for &(ref pending_forward, ref htlc_id) in self.monitor_pending_forwards.iter() {
4525                         pending_forward.write(writer)?;
4526                         htlc_id.write(writer)?;
4527                 }
4528
4529                 (self.monitor_pending_failures.len() as u64).write(writer)?;
4530                 for &(ref htlc_source, ref payment_hash, ref fail_reason) in self.monitor_pending_failures.iter() {
4531                         htlc_source.write(writer)?;
4532                         payment_hash.write(writer)?;
4533                         fail_reason.write(writer)?;
4534                 }
4535
4536                 self.pending_update_fee.write(writer)?;
4537                 self.holding_cell_update_fee.write(writer)?;
4538
4539                 self.next_holder_htlc_id.write(writer)?;
4540                 (self.next_counterparty_htlc_id - dropped_inbound_htlcs).write(writer)?;
4541                 self.update_time_counter.write(writer)?;
4542                 self.feerate_per_kw.write(writer)?;
4543
4544                 match self.last_sent_closing_fee {
4545                         Some((feerate, fee, sig)) => {
4546                                 1u8.write(writer)?;
4547                                 feerate.write(writer)?;
4548                                 fee.write(writer)?;
4549                                 sig.write(writer)?;
4550                         },
4551                         None => 0u8.write(writer)?,
4552                 }
4553
4554                 self.funding_tx_confirmed_in.write(writer)?;
4555                 self.funding_tx_confirmation_height.write(writer)?;
4556                 self.short_channel_id.write(writer)?;
4557
4558                 self.counterparty_dust_limit_satoshis.write(writer)?;
4559                 self.holder_dust_limit_satoshis.write(writer)?;
4560                 self.counterparty_max_htlc_value_in_flight_msat.write(writer)?;
4561                 self.counterparty_selected_channel_reserve_satoshis.write(writer)?;
4562                 self.counterparty_htlc_minimum_msat.write(writer)?;
4563                 self.holder_htlc_minimum_msat.write(writer)?;
4564                 self.counterparty_max_accepted_htlcs.write(writer)?;
4565                 self.minimum_depth.write(writer)?;
4566
4567                 match &self.counterparty_forwarding_info {
4568                         Some(info) => {
4569                                 1u8.write(writer)?;
4570                                 info.fee_base_msat.write(writer)?;
4571                                 info.fee_proportional_millionths.write(writer)?;
4572                                 info.cltv_expiry_delta.write(writer)?;
4573                         },
4574                         None => 0u8.write(writer)?
4575                 }
4576
4577                 self.channel_transaction_parameters.write(writer)?;
4578                 self.funding_transaction.write(writer)?;
4579
4580                 self.counterparty_cur_commitment_point.write(writer)?;
4581                 self.counterparty_prev_commitment_point.write(writer)?;
4582                 self.counterparty_node_id.write(writer)?;
4583
4584                 self.counterparty_shutdown_scriptpubkey.write(writer)?;
4585
4586                 self.commitment_secrets.write(writer)?;
4587
4588                 self.channel_update_status.write(writer)?;
4589                 Ok(())
4590         }
4591 }
4592
4593 const MAX_ALLOC_SIZE: usize = 64*1024;
4594 impl<'a, Signer: Sign, K: Deref> ReadableArgs<&'a K> for Channel<Signer>
4595                 where K::Target: KeysInterface<Signer = Signer> {
4596         fn read<R : ::std::io::Read>(reader: &mut R, keys_source: &'a K) -> Result<Self, DecodeError> {
4597                 let _ver: u8 = Readable::read(reader)?;
4598                 let min_ver: u8 = Readable::read(reader)?;
4599                 if min_ver > SERIALIZATION_VERSION {
4600                         return Err(DecodeError::UnknownVersion);
4601                 }
4602
4603                 let user_id = Readable::read(reader)?;
4604                 let config: ChannelConfig = Readable::read(reader)?;
4605
4606                 let channel_id = Readable::read(reader)?;
4607                 let channel_state = Readable::read(reader)?;
4608                 let channel_value_satoshis = Readable::read(reader)?;
4609
4610                 let latest_monitor_update_id = Readable::read(reader)?;
4611
4612                 let keys_len: u32 = Readable::read(reader)?;
4613                 let mut keys_data = Vec::with_capacity(cmp::min(keys_len as usize, MAX_ALLOC_SIZE));
4614                 while keys_data.len() != keys_len as usize {
4615                         // Read 1KB at a time to avoid accidentally allocating 4GB on corrupted channel keys
4616                         let mut data = [0; 1024];
4617                         let read_slice = &mut data[0..cmp::min(1024, keys_len as usize - keys_data.len())];
4618                         reader.read_exact(read_slice)?;
4619                         keys_data.extend_from_slice(read_slice);
4620                 }
4621                 let holder_signer = keys_source.read_chan_signer(&keys_data)?;
4622
4623                 let shutdown_pubkey = Readable::read(reader)?;
4624                 let destination_script = Readable::read(reader)?;
4625
4626                 let cur_holder_commitment_transaction_number = Readable::read(reader)?;
4627                 let cur_counterparty_commitment_transaction_number = Readable::read(reader)?;
4628                 let value_to_self_msat = Readable::read(reader)?;
4629
4630                 let pending_inbound_htlc_count: u64 = Readable::read(reader)?;
4631                 let mut pending_inbound_htlcs = Vec::with_capacity(cmp::min(pending_inbound_htlc_count as usize, OUR_MAX_HTLCS as usize));
4632                 for _ in 0..pending_inbound_htlc_count {
4633                         pending_inbound_htlcs.push(InboundHTLCOutput {
4634                                 htlc_id: Readable::read(reader)?,
4635                                 amount_msat: Readable::read(reader)?,
4636                                 cltv_expiry: Readable::read(reader)?,
4637                                 payment_hash: Readable::read(reader)?,
4638                                 state: match <u8 as Readable>::read(reader)? {
4639                                         1 => InboundHTLCState::AwaitingRemoteRevokeToAnnounce(Readable::read(reader)?),
4640                                         2 => InboundHTLCState::AwaitingAnnouncedRemoteRevoke(Readable::read(reader)?),
4641                                         3 => InboundHTLCState::Committed,
4642                                         4 => InboundHTLCState::LocalRemoved(Readable::read(reader)?),
4643                                         _ => return Err(DecodeError::InvalidValue),
4644                                 },
4645                         });
4646                 }
4647
4648                 let pending_outbound_htlc_count: u64 = Readable::read(reader)?;
4649                 let mut pending_outbound_htlcs = Vec::with_capacity(cmp::min(pending_outbound_htlc_count as usize, OUR_MAX_HTLCS as usize));
4650                 for _ in 0..pending_outbound_htlc_count {
4651                         pending_outbound_htlcs.push(OutboundHTLCOutput {
4652                                 htlc_id: Readable::read(reader)?,
4653                                 amount_msat: Readable::read(reader)?,
4654                                 cltv_expiry: Readable::read(reader)?,
4655                                 payment_hash: Readable::read(reader)?,
4656                                 source: Readable::read(reader)?,
4657                                 state: match <u8 as Readable>::read(reader)? {
4658                                         0 => OutboundHTLCState::LocalAnnounced(Box::new(Readable::read(reader)?)),
4659                                         1 => OutboundHTLCState::Committed,
4660                                         2 => OutboundHTLCState::RemoteRemoved(Readable::read(reader)?),
4661                                         3 => OutboundHTLCState::AwaitingRemoteRevokeToRemove(Readable::read(reader)?),
4662                                         4 => OutboundHTLCState::AwaitingRemovedRemoteRevoke(Readable::read(reader)?),
4663                                         _ => return Err(DecodeError::InvalidValue),
4664                                 },
4665                         });
4666                 }
4667
4668                 let holding_cell_htlc_update_count: u64 = Readable::read(reader)?;
4669                 let mut holding_cell_htlc_updates = Vec::with_capacity(cmp::min(holding_cell_htlc_update_count as usize, OUR_MAX_HTLCS as usize*2));
4670                 for _ in 0..holding_cell_htlc_update_count {
4671                         holding_cell_htlc_updates.push(match <u8 as Readable>::read(reader)? {
4672                                 0 => HTLCUpdateAwaitingACK::AddHTLC {
4673                                         amount_msat: Readable::read(reader)?,
4674                                         cltv_expiry: Readable::read(reader)?,
4675                                         payment_hash: Readable::read(reader)?,
4676                                         source: Readable::read(reader)?,
4677                                         onion_routing_packet: Readable::read(reader)?,
4678                                 },
4679                                 1 => HTLCUpdateAwaitingACK::ClaimHTLC {
4680                                         payment_preimage: Readable::read(reader)?,
4681                                         htlc_id: Readable::read(reader)?,
4682                                 },
4683                                 2 => HTLCUpdateAwaitingACK::FailHTLC {
4684                                         htlc_id: Readable::read(reader)?,
4685                                         err_packet: Readable::read(reader)?,
4686                                 },
4687                                 _ => return Err(DecodeError::InvalidValue),
4688                         });
4689                 }
4690
4691                 let resend_order = match <u8 as Readable>::read(reader)? {
4692                         0 => RAACommitmentOrder::CommitmentFirst,
4693                         1 => RAACommitmentOrder::RevokeAndACKFirst,
4694                         _ => return Err(DecodeError::InvalidValue),
4695                 };
4696
4697                 let monitor_pending_funding_locked = Readable::read(reader)?;
4698                 let monitor_pending_revoke_and_ack = Readable::read(reader)?;
4699                 let monitor_pending_commitment_signed = Readable::read(reader)?;
4700
4701                 let monitor_pending_forwards_count: u64 = Readable::read(reader)?;
4702                 let mut monitor_pending_forwards = Vec::with_capacity(cmp::min(monitor_pending_forwards_count as usize, OUR_MAX_HTLCS as usize));
4703                 for _ in 0..monitor_pending_forwards_count {
4704                         monitor_pending_forwards.push((Readable::read(reader)?, Readable::read(reader)?));
4705                 }
4706
4707                 let monitor_pending_failures_count: u64 = Readable::read(reader)?;
4708                 let mut monitor_pending_failures = Vec::with_capacity(cmp::min(monitor_pending_failures_count as usize, OUR_MAX_HTLCS as usize));
4709                 for _ in 0..monitor_pending_failures_count {
4710                         monitor_pending_failures.push((Readable::read(reader)?, Readable::read(reader)?, Readable::read(reader)?));
4711                 }
4712
4713                 let pending_update_fee = Readable::read(reader)?;
4714                 let holding_cell_update_fee = Readable::read(reader)?;
4715
4716                 let next_holder_htlc_id = Readable::read(reader)?;
4717                 let next_counterparty_htlc_id = Readable::read(reader)?;
4718                 let update_time_counter = Readable::read(reader)?;
4719                 let feerate_per_kw = Readable::read(reader)?;
4720
4721                 let last_sent_closing_fee = match <u8 as Readable>::read(reader)? {
4722                         0 => None,
4723                         1 => Some((Readable::read(reader)?, Readable::read(reader)?, Readable::read(reader)?)),
4724                         _ => return Err(DecodeError::InvalidValue),
4725                 };
4726
4727                 let funding_tx_confirmed_in = Readable::read(reader)?;
4728                 let funding_tx_confirmation_height = Readable::read(reader)?;
4729                 let short_channel_id = Readable::read(reader)?;
4730
4731                 let counterparty_dust_limit_satoshis = Readable::read(reader)?;
4732                 let holder_dust_limit_satoshis = Readable::read(reader)?;
4733                 let counterparty_max_htlc_value_in_flight_msat = Readable::read(reader)?;
4734                 let counterparty_selected_channel_reserve_satoshis = Readable::read(reader)?;
4735                 let counterparty_htlc_minimum_msat = Readable::read(reader)?;
4736                 let holder_htlc_minimum_msat = Readable::read(reader)?;
4737                 let counterparty_max_accepted_htlcs = Readable::read(reader)?;
4738                 let minimum_depth = Readable::read(reader)?;
4739
4740                 let counterparty_forwarding_info = match <u8 as Readable>::read(reader)? {
4741                         0 => None,
4742                         1 => Some(CounterpartyForwardingInfo {
4743                                 fee_base_msat: Readable::read(reader)?,
4744                                 fee_proportional_millionths: Readable::read(reader)?,
4745                                 cltv_expiry_delta: Readable::read(reader)?,
4746                         }),
4747                         _ => return Err(DecodeError::InvalidValue),
4748                 };
4749
4750                 let channel_parameters = Readable::read(reader)?;
4751                 let funding_transaction = Readable::read(reader)?;
4752
4753                 let counterparty_cur_commitment_point = Readable::read(reader)?;
4754
4755                 let counterparty_prev_commitment_point = Readable::read(reader)?;
4756                 let counterparty_node_id = Readable::read(reader)?;
4757
4758                 let counterparty_shutdown_scriptpubkey = Readable::read(reader)?;
4759                 let commitment_secrets = Readable::read(reader)?;
4760
4761                 let channel_update_status = Readable::read(reader)?;
4762
4763                 let mut secp_ctx = Secp256k1::new();
4764                 secp_ctx.seeded_randomize(&keys_source.get_secure_random_bytes());
4765
4766                 Ok(Channel {
4767                         user_id,
4768
4769                         config,
4770                         channel_id,
4771                         channel_state,
4772                         secp_ctx,
4773                         channel_value_satoshis,
4774
4775                         latest_monitor_update_id,
4776
4777                         holder_signer,
4778                         shutdown_pubkey,
4779                         destination_script,
4780
4781                         cur_holder_commitment_transaction_number,
4782                         cur_counterparty_commitment_transaction_number,
4783                         value_to_self_msat,
4784
4785                         pending_inbound_htlcs,
4786                         pending_outbound_htlcs,
4787                         holding_cell_htlc_updates,
4788
4789                         resend_order,
4790
4791                         monitor_pending_funding_locked,
4792                         monitor_pending_revoke_and_ack,
4793                         monitor_pending_commitment_signed,
4794                         monitor_pending_forwards,
4795                         monitor_pending_failures,
4796
4797                         pending_update_fee,
4798                         holding_cell_update_fee,
4799                         next_holder_htlc_id,
4800                         next_counterparty_htlc_id,
4801                         update_time_counter,
4802                         feerate_per_kw,
4803
4804                         #[cfg(debug_assertions)]
4805                         holder_max_commitment_tx_output: ::std::sync::Mutex::new((0, 0)),
4806                         #[cfg(debug_assertions)]
4807                         counterparty_max_commitment_tx_output: ::std::sync::Mutex::new((0, 0)),
4808
4809                         last_sent_closing_fee,
4810
4811                         funding_tx_confirmed_in,
4812                         funding_tx_confirmation_height,
4813                         short_channel_id,
4814
4815                         counterparty_dust_limit_satoshis,
4816                         holder_dust_limit_satoshis,
4817                         counterparty_max_htlc_value_in_flight_msat,
4818                         counterparty_selected_channel_reserve_satoshis,
4819                         counterparty_htlc_minimum_msat,
4820                         holder_htlc_minimum_msat,
4821                         counterparty_max_accepted_htlcs,
4822                         minimum_depth,
4823
4824                         counterparty_forwarding_info,
4825
4826                         channel_transaction_parameters: channel_parameters,
4827                         funding_transaction,
4828
4829                         counterparty_cur_commitment_point,
4830                         counterparty_prev_commitment_point,
4831                         counterparty_node_id,
4832
4833                         counterparty_shutdown_scriptpubkey,
4834
4835                         commitment_secrets,
4836
4837                         channel_update_status,
4838
4839                         #[cfg(any(test, feature = "fuzztarget"))]
4840                         next_local_commitment_tx_fee_info_cached: Mutex::new(None),
4841                         #[cfg(any(test, feature = "fuzztarget"))]
4842                         next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
4843                 })
4844         }
4845 }
4846
4847 #[cfg(test)]
4848 mod tests {
4849         use bitcoin::util::bip143;
4850         use bitcoin::consensus::encode::serialize;
4851         use bitcoin::blockdata::script::{Script, Builder};
4852         use bitcoin::blockdata::transaction::{Transaction, TxOut, SigHashType};
4853         use bitcoin::blockdata::constants::genesis_block;
4854         use bitcoin::blockdata::opcodes;
4855         use bitcoin::network::constants::Network;
4856         use bitcoin::hashes::hex::FromHex;
4857         use hex;
4858         use ln::{PaymentPreimage, PaymentHash};
4859         use ln::channelmanager::{BestBlock, HTLCSource};
4860         use ln::channel::{Channel,InboundHTLCOutput,OutboundHTLCOutput,InboundHTLCState,OutboundHTLCState,HTLCOutputInCommitment,HTLCCandidate,HTLCInitiator,TxCreationKeys};
4861         use ln::channel::MAX_FUNDING_SATOSHIS;
4862         use ln::features::InitFeatures;
4863         use ln::msgs::{ChannelUpdate, DataLossProtect, DecodeError, OptionalField, UnsignedChannelUpdate};
4864         use ln::chan_utils;
4865         use ln::chan_utils::{ChannelPublicKeys, HolderCommitmentTransaction, CounterpartyChannelTransactionParameters, HTLC_SUCCESS_TX_WEIGHT, HTLC_TIMEOUT_TX_WEIGHT};
4866         use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
4867         use chain::keysinterface::{InMemorySigner, KeysInterface, BaseSign};
4868         use chain::transaction::OutPoint;
4869         use util::config::UserConfig;
4870         use util::enforcing_trait_impls::EnforcingSigner;
4871         use util::test_utils;
4872         use util::logger::Logger;
4873         use bitcoin::secp256k1::{Secp256k1, Message, Signature, All};
4874         use bitcoin::secp256k1::ffi::Signature as FFISignature;
4875         use bitcoin::secp256k1::key::{SecretKey,PublicKey};
4876         use bitcoin::secp256k1::recovery::RecoverableSignature;
4877         use bitcoin::hashes::sha256::Hash as Sha256;
4878         use bitcoin::hashes::Hash;
4879         use bitcoin::hash_types::{Txid, WPubkeyHash};
4880         use std::sync::Arc;
4881
4882         struct TestFeeEstimator {
4883                 fee_est: u32
4884         }
4885         impl FeeEstimator for TestFeeEstimator {
4886                 fn get_est_sat_per_1000_weight(&self, _: ConfirmationTarget) -> u32 {
4887                         self.fee_est
4888                 }
4889         }
4890
4891         #[test]
4892         fn test_max_funding_satoshis() {
4893                 assert!(MAX_FUNDING_SATOSHIS <= 21_000_000 * 100_000_000,
4894                         "MAX_FUNDING_SATOSHIS is greater than all satoshis in existence");
4895         }
4896
4897         struct Keys {
4898                 signer: InMemorySigner,
4899         }
4900         impl KeysInterface for Keys {
4901                 type Signer = InMemorySigner;
4902
4903                 fn get_node_secret(&self) -> SecretKey { panic!(); }
4904                 fn get_destination_script(&self) -> Script {
4905                         let secp_ctx = Secp256k1::signing_only();
4906                         let channel_monitor_claim_key = SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap();
4907                         let channel_monitor_claim_key_hash = WPubkeyHash::hash(&PublicKey::from_secret_key(&secp_ctx, &channel_monitor_claim_key).serialize());
4908                         Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&channel_monitor_claim_key_hash[..]).into_script()
4909                 }
4910
4911                 fn get_shutdown_pubkey(&self) -> PublicKey {
4912                         let secp_ctx = Secp256k1::signing_only();
4913                         let channel_close_key = SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap();
4914                         PublicKey::from_secret_key(&secp_ctx, &channel_close_key)
4915                 }
4916
4917                 fn get_channel_signer(&self, _inbound: bool, _channel_value_satoshis: u64) -> InMemorySigner {
4918                         self.signer.clone()
4919                 }
4920                 fn get_secure_random_bytes(&self) -> [u8; 32] { [0; 32] }
4921                 fn read_chan_signer(&self, _data: &[u8]) -> Result<Self::Signer, DecodeError> { panic!(); }
4922                 fn sign_invoice(&self, _invoice_preimage: Vec<u8>) -> Result<RecoverableSignature, ()> { panic!(); }
4923         }
4924
4925         fn public_from_secret_hex(secp_ctx: &Secp256k1<All>, hex: &str) -> PublicKey {
4926                 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode(hex).unwrap()[..]).unwrap())
4927         }
4928
4929         // Check that, during channel creation, we use the same feerate in the open channel message
4930         // as we do in the Channel object creation itself.
4931         #[test]
4932         fn test_open_channel_msg_fee() {
4933                 let original_fee = 253;
4934                 let mut fee_est = TestFeeEstimator{fee_est: original_fee };
4935                 let secp_ctx = Secp256k1::new();
4936                 let seed = [42; 32];
4937                 let network = Network::Testnet;
4938                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
4939
4940                 let node_a_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
4941                 let config = UserConfig::default();
4942                 let node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&fee_est, &&keys_provider, node_a_node_id, 10000000, 100000, 42, &config).unwrap();
4943
4944                 // Now change the fee so we can check that the fee in the open_channel message is the
4945                 // same as the old fee.
4946                 fee_est.fee_est = 500;
4947                 let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.block_hash());
4948                 assert_eq!(open_channel_msg.feerate_per_kw, original_fee);
4949         }
4950
4951         #[test]
4952         fn test_holder_vs_counterparty_dust_limit() {
4953                 // Test that when calculating the local and remote commitment transaction fees, the correct
4954                 // dust limits are used.
4955                 let feeest = TestFeeEstimator{fee_est: 15000};
4956                 let secp_ctx = Secp256k1::new();
4957                 let seed = [42; 32];
4958                 let network = Network::Testnet;
4959                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
4960
4961                 // Go through the flow of opening a channel between two nodes, making sure
4962                 // they have different dust limits.
4963
4964                 // Create Node A's channel pointing to Node B's pubkey
4965                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
4966                 let config = UserConfig::default();
4967                 let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, 10000000, 100000, 42, &config).unwrap();
4968
4969                 // Create Node B's channel by receiving Node A's open_channel message
4970                 // Make sure A's dust limit is as we expect.
4971                 let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.block_hash());
4972                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
4973                 let node_b_chan = Channel::<EnforcingSigner>::new_from_req(&&feeest, &&keys_provider, node_b_node_id, InitFeatures::known(), &open_channel_msg, 7, &config).unwrap();
4974
4975                 // Node B --> Node A: accept channel, explicitly setting B's dust limit.
4976                 let mut accept_channel_msg = node_b_chan.get_accept_channel();
4977                 accept_channel_msg.dust_limit_satoshis = 546;
4978                 node_a_chan.accept_channel(&accept_channel_msg, &config, InitFeatures::known()).unwrap();
4979                 node_a_chan.holder_dust_limit_satoshis = 1560;
4980
4981                 // Put some inbound and outbound HTLCs in A's channel.
4982                 let htlc_amount_msat = 11_092_000; // put an amount below A's effective dust limit but above B's.
4983                 node_a_chan.pending_inbound_htlcs.push(InboundHTLCOutput {
4984                         htlc_id: 0,
4985                         amount_msat: htlc_amount_msat,
4986                         payment_hash: PaymentHash(Sha256::hash(&[42; 32]).into_inner()),
4987                         cltv_expiry: 300000000,
4988                         state: InboundHTLCState::Committed,
4989                 });
4990
4991                 node_a_chan.pending_outbound_htlcs.push(OutboundHTLCOutput {
4992                         htlc_id: 1,
4993                         amount_msat: htlc_amount_msat, // put an amount below A's dust amount but above B's.
4994                         payment_hash: PaymentHash(Sha256::hash(&[43; 32]).into_inner()),
4995                         cltv_expiry: 200000000,
4996                         state: OutboundHTLCState::Committed,
4997                         source: HTLCSource::OutboundRoute {
4998                                 path: Vec::new(),
4999                                 session_priv: SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(),
5000                                 first_hop_htlc_msat: 548,
5001                         }
5002                 });
5003
5004                 // Make sure when Node A calculates their local commitment transaction, none of the HTLCs pass
5005                 // the dust limit check.
5006                 let htlc_candidate = HTLCCandidate::new(htlc_amount_msat, HTLCInitiator::LocalOffered);
5007                 let local_commit_tx_fee = node_a_chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
5008                 let local_commit_fee_0_htlcs = node_a_chan.commit_tx_fee_msat(0);
5009                 assert_eq!(local_commit_tx_fee, local_commit_fee_0_htlcs);
5010
5011                 // Finally, make sure that when Node A calculates the remote's commitment transaction fees, all
5012                 // of the HTLCs are seen to be above the dust limit.
5013                 node_a_chan.channel_transaction_parameters.is_outbound_from_holder = false;
5014                 let remote_commit_fee_3_htlcs = node_a_chan.commit_tx_fee_msat(3);
5015                 let htlc_candidate = HTLCCandidate::new(htlc_amount_msat, HTLCInitiator::LocalOffered);
5016                 let remote_commit_tx_fee = node_a_chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
5017                 assert_eq!(remote_commit_tx_fee, remote_commit_fee_3_htlcs);
5018         }
5019
5020         #[test]
5021         fn test_timeout_vs_success_htlc_dust_limit() {
5022                 // Make sure that when `next_remote_commit_tx_fee_msat` and `next_local_commit_tx_fee_msat`
5023                 // calculate the real dust limits for HTLCs (i.e. the dust limit given by the counterparty
5024                 // *plus* the fees paid for the HTLC) they don't swap `HTLC_SUCCESS_TX_WEIGHT` for
5025                 // `HTLC_TIMEOUT_TX_WEIGHT`, and vice versa.
5026                 let fee_est = TestFeeEstimator{fee_est: 253 };
5027                 let secp_ctx = Secp256k1::new();
5028                 let seed = [42; 32];
5029                 let network = Network::Testnet;
5030                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5031
5032                 let node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5033                 let config = UserConfig::default();
5034                 let mut chan = Channel::<EnforcingSigner>::new_outbound(&&fee_est, &&keys_provider, node_id, 10000000, 100000, 42, &config).unwrap();
5035
5036                 let commitment_tx_fee_0_htlcs = chan.commit_tx_fee_msat(0);
5037                 let commitment_tx_fee_1_htlc = chan.commit_tx_fee_msat(1);
5038
5039                 // If HTLC_SUCCESS_TX_WEIGHT and HTLC_TIMEOUT_TX_WEIGHT were swapped: then this HTLC would be
5040                 // counted as dust when it shouldn't be.
5041                 let htlc_amt_above_timeout = ((253 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + chan.holder_dust_limit_satoshis + 1) * 1000;
5042                 let htlc_candidate = HTLCCandidate::new(htlc_amt_above_timeout, HTLCInitiator::LocalOffered);
5043                 let commitment_tx_fee = chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
5044                 assert_eq!(commitment_tx_fee, commitment_tx_fee_1_htlc);
5045
5046                 // If swapped: this HTLC would be counted as non-dust when it shouldn't be.
5047                 let dust_htlc_amt_below_success = ((253 * HTLC_SUCCESS_TX_WEIGHT / 1000) + chan.holder_dust_limit_satoshis - 1) * 1000;
5048                 let htlc_candidate = HTLCCandidate::new(dust_htlc_amt_below_success, HTLCInitiator::RemoteOffered);
5049                 let commitment_tx_fee = chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
5050                 assert_eq!(commitment_tx_fee, commitment_tx_fee_0_htlcs);
5051
5052                 chan.channel_transaction_parameters.is_outbound_from_holder = false;
5053
5054                 // If swapped: this HTLC would be counted as non-dust when it shouldn't be.
5055                 let dust_htlc_amt_above_timeout = ((253 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + chan.counterparty_dust_limit_satoshis + 1) * 1000;
5056                 let htlc_candidate = HTLCCandidate::new(dust_htlc_amt_above_timeout, HTLCInitiator::LocalOffered);
5057                 let commitment_tx_fee = chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
5058                 assert_eq!(commitment_tx_fee, commitment_tx_fee_0_htlcs);
5059
5060                 // If swapped: this HTLC would be counted as dust when it shouldn't be.
5061                 let htlc_amt_below_success = ((253 * HTLC_SUCCESS_TX_WEIGHT / 1000) + chan.counterparty_dust_limit_satoshis - 1) * 1000;
5062                 let htlc_candidate = HTLCCandidate::new(htlc_amt_below_success, HTLCInitiator::RemoteOffered);
5063                 let commitment_tx_fee = chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
5064                 assert_eq!(commitment_tx_fee, commitment_tx_fee_1_htlc);
5065         }
5066
5067         #[test]
5068         fn channel_reestablish_no_updates() {
5069                 let feeest = TestFeeEstimator{fee_est: 15000};
5070                 let logger = test_utils::TestLogger::new();
5071                 let secp_ctx = Secp256k1::new();
5072                 let seed = [42; 32];
5073                 let network = Network::Testnet;
5074                 let best_block = BestBlock::from_genesis(network);
5075                 let chain_hash = best_block.block_hash();
5076                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5077
5078                 // Go through the flow of opening a channel between two nodes.
5079
5080                 // Create Node A's channel pointing to Node B's pubkey
5081                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5082                 let config = UserConfig::default();
5083                 let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, 10000000, 100000, 42, &config).unwrap();
5084
5085                 // Create Node B's channel by receiving Node A's open_channel message
5086                 let open_channel_msg = node_a_chan.get_open_channel(chain_hash);
5087                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
5088                 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();
5089
5090                 // Node B --> Node A: accept channel
5091                 let accept_channel_msg = node_b_chan.get_accept_channel();
5092                 node_a_chan.accept_channel(&accept_channel_msg, &config, InitFeatures::known()).unwrap();
5093
5094                 // Node A --> Node B: funding created
5095                 let output_script = node_a_chan.get_funding_redeemscript();
5096                 let tx = Transaction { version: 1, lock_time: 0, input: Vec::new(), output: vec![TxOut {
5097                         value: 10000000, script_pubkey: output_script.clone(),
5098                 }]};
5099                 let funding_outpoint = OutPoint{ txid: tx.txid(), index: 0 };
5100                 let funding_created_msg = node_a_chan.get_outbound_funding_created(tx.clone(), funding_outpoint, &&logger).unwrap();
5101                 let (funding_signed_msg, _) = node_b_chan.funding_created(&funding_created_msg, best_block, &&logger).unwrap();
5102
5103                 // Node B --> Node A: funding signed
5104                 let _ = node_a_chan.funding_signed(&funding_signed_msg, best_block, &&logger);
5105
5106                 // Now disconnect the two nodes and check that the commitment point in
5107                 // Node B's channel_reestablish message is sane.
5108                 node_b_chan.remove_uncommitted_htlcs_and_mark_paused(&&logger);
5109                 let msg = node_b_chan.get_channel_reestablish(&&logger);
5110                 assert_eq!(msg.next_local_commitment_number, 1); // now called next_commitment_number
5111                 assert_eq!(msg.next_remote_commitment_number, 0); // now called next_revocation_number
5112                 match msg.data_loss_protect {
5113                         OptionalField::Present(DataLossProtect { your_last_per_commitment_secret, .. }) => {
5114                                 assert_eq!(your_last_per_commitment_secret, [0; 32]);
5115                         },
5116                         _ => panic!()
5117                 }
5118
5119                 // Check that the commitment point in Node A's channel_reestablish message
5120                 // is sane.
5121                 node_a_chan.remove_uncommitted_htlcs_and_mark_paused(&&logger);
5122                 let msg = node_a_chan.get_channel_reestablish(&&logger);
5123                 assert_eq!(msg.next_local_commitment_number, 1); // now called next_commitment_number
5124                 assert_eq!(msg.next_remote_commitment_number, 0); // now called next_revocation_number
5125                 match msg.data_loss_protect {
5126                         OptionalField::Present(DataLossProtect { your_last_per_commitment_secret, .. }) => {
5127                                 assert_eq!(your_last_per_commitment_secret, [0; 32]);
5128                         },
5129                         _ => panic!()
5130                 }
5131         }
5132
5133         #[test]
5134         fn channel_update() {
5135                 let feeest = TestFeeEstimator{fee_est: 15000};
5136                 let secp_ctx = Secp256k1::new();
5137                 let seed = [42; 32];
5138                 let network = Network::Testnet;
5139                 let chain_hash = genesis_block(network).header.block_hash();
5140                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5141
5142                 // Create a channel.
5143                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5144                 let config = UserConfig::default();
5145                 let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, 10000000, 100000, 42, &config).unwrap();
5146                 assert!(node_a_chan.counterparty_forwarding_info.is_none());
5147                 assert_eq!(node_a_chan.holder_htlc_minimum_msat, 1); // the default
5148                 assert!(node_a_chan.counterparty_forwarding_info().is_none());
5149
5150                 // Make sure that receiving a channel update will update the Channel as expected.
5151                 let update = ChannelUpdate {
5152                         contents: UnsignedChannelUpdate {
5153                                 chain_hash,
5154                                 short_channel_id: 0,
5155                                 timestamp: 0,
5156                                 flags: 0,
5157                                 cltv_expiry_delta: 100,
5158                                 htlc_minimum_msat: 5,
5159                                 htlc_maximum_msat: OptionalField::Absent,
5160                                 fee_base_msat: 110,
5161                                 fee_proportional_millionths: 11,
5162                                 excess_data: Vec::new(),
5163                         },
5164                         signature: Signature::from(unsafe { FFISignature::new() })
5165                 };
5166                 node_a_chan.channel_update(&update).unwrap();
5167
5168                 // The counterparty can send an update with a higher minimum HTLC, but that shouldn't
5169                 // change our official htlc_minimum_msat.
5170                 assert_eq!(node_a_chan.holder_htlc_minimum_msat, 1);
5171                 match node_a_chan.counterparty_forwarding_info() {
5172                         Some(info) => {
5173                                 assert_eq!(info.cltv_expiry_delta, 100);
5174                                 assert_eq!(info.fee_base_msat, 110);
5175                                 assert_eq!(info.fee_proportional_millionths, 11);
5176                         },
5177                         None => panic!("expected counterparty forwarding info to be Some")
5178                 }
5179         }
5180
5181         #[test]
5182         fn outbound_commitment_test() {
5183                 // Test vectors from BOLT 3 Appendix C:
5184                 let feeest = TestFeeEstimator{fee_est: 15000};
5185                 let logger : Arc<Logger> = Arc::new(test_utils::TestLogger::new());
5186                 let secp_ctx = Secp256k1::new();
5187
5188                 let mut signer = InMemorySigner::new(
5189                         &secp_ctx,
5190                         SecretKey::from_slice(&hex::decode("30ff4956bbdd3222d44cc5e8a1261dab1e07957bdac5ae88fe3261ef321f3749").unwrap()[..]).unwrap(),
5191                         SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(),
5192                         SecretKey::from_slice(&hex::decode("1111111111111111111111111111111111111111111111111111111111111111").unwrap()[..]).unwrap(),
5193                         SecretKey::from_slice(&hex::decode("3333333333333333333333333333333333333333333333333333333333333333").unwrap()[..]).unwrap(),
5194                         SecretKey::from_slice(&hex::decode("1111111111111111111111111111111111111111111111111111111111111111").unwrap()[..]).unwrap(),
5195
5196                         // These aren't set in the test vectors:
5197                         [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],
5198                         10_000_000,
5199                         [0; 32]
5200                 );
5201
5202                 assert_eq!(signer.pubkeys().funding_pubkey.serialize()[..],
5203                                 hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]);
5204                 let keys_provider = Keys { signer: signer.clone() };
5205
5206                 let counterparty_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5207                 let mut config = UserConfig::default();
5208                 config.channel_options.announced_channel = false;
5209                 let mut chan = Channel::<InMemorySigner>::new_outbound(&&feeest, &&keys_provider, counterparty_node_id, 10_000_000, 100000, 42, &config).unwrap(); // Nothing uses their network key in this test
5210                 chan.holder_dust_limit_satoshis = 546;
5211
5212                 let funding_info = OutPoint{ txid: Txid::from_hex("8984484a580b825b9972d7adb15050b3ab624ccd731946b3eeddb92f4e7ef6be").unwrap(), index: 0 };
5213
5214                 let counterparty_pubkeys = ChannelPublicKeys {
5215                         funding_pubkey: public_from_secret_hex(&secp_ctx, "1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13"),
5216                         revocation_basepoint: PublicKey::from_slice(&hex::decode("02466d7fcae563e5cb09a0d1870bb580344804617879a14949cf22285f1bae3f27").unwrap()[..]).unwrap(),
5217                         payment_point: public_from_secret_hex(&secp_ctx, "4444444444444444444444444444444444444444444444444444444444444444"),
5218                         delayed_payment_basepoint: public_from_secret_hex(&secp_ctx, "1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13"),
5219                         htlc_basepoint: public_from_secret_hex(&secp_ctx, "4444444444444444444444444444444444444444444444444444444444444444")
5220                 };
5221                 chan.channel_transaction_parameters.counterparty_parameters = Some(
5222                         CounterpartyChannelTransactionParameters {
5223                                 pubkeys: counterparty_pubkeys.clone(),
5224                                 selected_contest_delay: 144
5225                         });
5226                 chan.channel_transaction_parameters.funding_outpoint = Some(funding_info);
5227                 signer.ready_channel(&chan.channel_transaction_parameters);
5228
5229                 assert_eq!(counterparty_pubkeys.payment_point.serialize()[..],
5230                            hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
5231
5232                 assert_eq!(counterparty_pubkeys.funding_pubkey.serialize()[..],
5233                            hex::decode("030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c1").unwrap()[..]);
5234
5235                 assert_eq!(counterparty_pubkeys.htlc_basepoint.serialize()[..],
5236                            hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
5237
5238                 // We can't just use build_holder_transaction_keys here as the per_commitment_secret is not
5239                 // derived from a commitment_seed, so instead we copy it here and call
5240                 // build_commitment_transaction.
5241                 let delayed_payment_base = &chan.holder_signer.pubkeys().delayed_payment_basepoint;
5242                 let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
5243                 let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
5244                 let htlc_basepoint = &chan.holder_signer.pubkeys().htlc_basepoint;
5245                 let keys = TxCreationKeys::derive_new(&secp_ctx, &per_commitment_point, delayed_payment_base, htlc_basepoint, &counterparty_pubkeys.revocation_basepoint, &counterparty_pubkeys.htlc_basepoint).unwrap();
5246
5247                 macro_rules! test_commitment {
5248                         ( $counterparty_sig_hex: expr, $sig_hex: expr, $tx_hex: expr, {
5249                                 $( { $htlc_idx: expr, $counterparty_htlc_sig_hex: expr, $htlc_sig_hex: expr, $htlc_tx_hex: expr } ), *
5250                         } ) => { {
5251                                 let (commitment_tx, htlcs): (_, Vec<HTLCOutputInCommitment>) = {
5252                                         let mut res = chan.build_commitment_transaction(0xffffffffffff - 42, &keys, true, false, chan.feerate_per_kw, &logger);
5253
5254                                         let htlcs = res.2.drain(..)
5255                                                 .filter_map(|(htlc, _)| if htlc.transaction_output_index.is_some() { Some(htlc) } else { None })
5256                                                 .collect();
5257                                         (res.0, htlcs)
5258                                 };
5259                                 let trusted_tx = commitment_tx.trust();
5260                                 let unsigned_tx = trusted_tx.built_transaction();
5261                                 let redeemscript = chan.get_funding_redeemscript();
5262                                 let counterparty_signature = Signature::from_der(&hex::decode($counterparty_sig_hex).unwrap()[..]).unwrap();
5263                                 let sighash = unsigned_tx.get_sighash_all(&redeemscript, chan.channel_value_satoshis);
5264                                 secp_ctx.verify(&sighash, &counterparty_signature, chan.counterparty_funding_pubkey()).unwrap();
5265
5266                                 let mut per_htlc: Vec<(HTLCOutputInCommitment, Option<Signature>)> = Vec::new();
5267                                 per_htlc.clear(); // Don't warn about excess mut for no-HTLC calls
5268                                 let mut counterparty_htlc_sigs = Vec::new();
5269                                 counterparty_htlc_sigs.clear(); // Don't warn about excess mut for no-HTLC calls
5270                                 $({
5271                                         let remote_signature = Signature::from_der(&hex::decode($counterparty_htlc_sig_hex).unwrap()[..]).unwrap();
5272                                         per_htlc.push((htlcs[$htlc_idx].clone(), Some(remote_signature)));
5273                                         counterparty_htlc_sigs.push(remote_signature);
5274                                 })*
5275                                 assert_eq!(htlcs.len(), per_htlc.len());
5276
5277                                 let holder_commitment_tx = HolderCommitmentTransaction::new(
5278                                         commitment_tx.clone(),
5279                                         counterparty_signature,
5280                                         counterparty_htlc_sigs,
5281                                         &chan.holder_signer.pubkeys().funding_pubkey,
5282                                         chan.counterparty_funding_pubkey()
5283                                 );
5284                                 let (holder_sig, htlc_sigs) = signer.sign_holder_commitment_and_htlcs(&holder_commitment_tx, &secp_ctx).unwrap();
5285                                 assert_eq!(Signature::from_der(&hex::decode($sig_hex).unwrap()[..]).unwrap(), holder_sig, "holder_sig");
5286
5287                                 let funding_redeemscript = chan.get_funding_redeemscript();
5288                                 let tx = holder_commitment_tx.add_holder_sig(&funding_redeemscript, holder_sig);
5289                                 assert_eq!(serialize(&tx)[..], hex::decode($tx_hex).unwrap()[..], "tx");
5290
5291                                 // ((htlc, counterparty_sig), (index, holder_sig))
5292                                 let mut htlc_sig_iter = holder_commitment_tx.htlcs().iter().zip(&holder_commitment_tx.counterparty_htlc_sigs).zip(htlc_sigs.iter().enumerate());
5293
5294                                 $({
5295                                         let remote_signature = Signature::from_der(&hex::decode($counterparty_htlc_sig_hex).unwrap()[..]).unwrap();
5296
5297                                         let ref htlc = htlcs[$htlc_idx];
5298                                         let htlc_tx = chan.build_htlc_transaction(&unsigned_tx.txid, &htlc, true, &keys, chan.feerate_per_kw);
5299                                         let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys);
5300                                         let htlc_sighash = Message::from_slice(&bip143::SigHashCache::new(&htlc_tx).signature_hash(0, &htlc_redeemscript, htlc.amount_msat / 1000, SigHashType::All)[..]).unwrap();
5301                                         secp_ctx.verify(&htlc_sighash, &remote_signature, &keys.countersignatory_htlc_key).unwrap();
5302
5303                                         let mut preimage: Option<PaymentPreimage> = None;
5304                                         if !htlc.offered {
5305                                                 for i in 0..5 {
5306                                                         let out = PaymentHash(Sha256::hash(&[i; 32]).into_inner());
5307                                                         if out == htlc.payment_hash {
5308                                                                 preimage = Some(PaymentPreimage([i; 32]));
5309                                                         }
5310                                                 }
5311
5312                                                 assert!(preimage.is_some());
5313                                         }
5314
5315                                         let htlc_sig = htlc_sig_iter.next().unwrap();
5316                                         assert_eq!((htlc_sig.0).0.transaction_output_index, Some($htlc_idx), "output index");
5317
5318                                         let signature = Signature::from_der(&hex::decode($htlc_sig_hex).unwrap()[..]).unwrap();
5319                                         assert_eq!(signature, *(htlc_sig.1).1, "htlc sig");
5320                                         let index = (htlc_sig.1).0;
5321                                         let channel_parameters = chan.channel_transaction_parameters.as_holder_broadcastable();
5322                                         let trusted_tx = holder_commitment_tx.trust();
5323                                         assert_eq!(serialize(&trusted_tx.get_signed_htlc_tx(&channel_parameters, index, &(htlc_sig.0).1, (htlc_sig.1).1, &preimage))[..],
5324                                                         hex::decode($htlc_tx_hex).unwrap()[..], "htlc tx");
5325                                 })*
5326                                 assert!(htlc_sig_iter.next().is_none());
5327                         } }
5328                 }
5329
5330                 // simple commitment tx with no HTLCs
5331                 chan.value_to_self_msat = 7000000000;
5332
5333                 test_commitment!("3045022100c3127b33dcc741dd6b05b1e63cbd1a9a7d816f37af9b6756fa2376b056f032370220408b96279808fe57eb7e463710804cdf4f108388bc5cf722d8c848d2c7f9f3b0",
5334                                                  "30440220616210b2cc4d3afb601013c373bbd8aac54febd9f15400379a8cb65ce7deca60022034236c010991beb7ff770510561ae8dc885b8d38d1947248c38f2ae055647142",
5335                                                  "02000000000101bef67e4e2fb9ddeeb3461973cd4c62abb35050b1add772995b820b584a488489000000000038b02b8002c0c62d0000000000160014cc1b07838e387deacd0e5232e1e8b49f4c29e48454a56a00000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e04004730440220616210b2cc4d3afb601013c373bbd8aac54febd9f15400379a8cb65ce7deca60022034236c010991beb7ff770510561ae8dc885b8d38d1947248c38f2ae05564714201483045022100c3127b33dcc741dd6b05b1e63cbd1a9a7d816f37af9b6756fa2376b056f032370220408b96279808fe57eb7e463710804cdf4f108388bc5cf722d8c848d2c7f9f3b001475221023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb21030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c152ae3e195220", {});
5336
5337                 chan.pending_inbound_htlcs.push({
5338                         let mut out = InboundHTLCOutput{
5339                                 htlc_id: 0,
5340                                 amount_msat: 1000000,
5341                                 cltv_expiry: 500,
5342                                 payment_hash: PaymentHash([0; 32]),
5343                                 state: InboundHTLCState::Committed,
5344                         };
5345                         out.payment_hash.0 = Sha256::hash(&hex::decode("0000000000000000000000000000000000000000000000000000000000000000").unwrap()).into_inner();
5346                         out
5347                 });
5348                 chan.pending_inbound_htlcs.push({
5349                         let mut out = InboundHTLCOutput{
5350                                 htlc_id: 1,
5351                                 amount_msat: 2000000,
5352                                 cltv_expiry: 501,
5353                                 payment_hash: PaymentHash([0; 32]),
5354                                 state: InboundHTLCState::Committed,
5355                         };
5356                         out.payment_hash.0 = Sha256::hash(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()).into_inner();
5357                         out
5358                 });
5359                 chan.pending_outbound_htlcs.push({
5360                         let mut out = OutboundHTLCOutput{
5361                                 htlc_id: 2,
5362                                 amount_msat: 2000000,
5363                                 cltv_expiry: 502,
5364                                 payment_hash: PaymentHash([0; 32]),
5365                                 state: OutboundHTLCState::Committed,
5366                                 source: HTLCSource::dummy(),
5367                         };
5368                         out.payment_hash.0 = Sha256::hash(&hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap()).into_inner();
5369                         out
5370                 });
5371                 chan.pending_outbound_htlcs.push({
5372                         let mut out = OutboundHTLCOutput{
5373                                 htlc_id: 3,
5374                                 amount_msat: 3000000,
5375                                 cltv_expiry: 503,
5376                                 payment_hash: PaymentHash([0; 32]),
5377                                 state: OutboundHTLCState::Committed,
5378                                 source: HTLCSource::dummy(),
5379                         };
5380                         out.payment_hash.0 = Sha256::hash(&hex::decode("0303030303030303030303030303030303030303030303030303030303030303").unwrap()).into_inner();
5381                         out
5382                 });
5383                 chan.pending_inbound_htlcs.push({
5384                         let mut out = InboundHTLCOutput{
5385                                 htlc_id: 4,
5386                                 amount_msat: 4000000,
5387                                 cltv_expiry: 504,
5388                                 payment_hash: PaymentHash([0; 32]),
5389                                 state: InboundHTLCState::Committed,
5390                         };
5391                         out.payment_hash.0 = Sha256::hash(&hex::decode("0404040404040404040404040404040404040404040404040404040404040404").unwrap()).into_inner();
5392                         out
5393                 });
5394
5395                 // commitment tx with all five HTLCs untrimmed (minimum feerate)
5396                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5397                 chan.feerate_per_kw = 0;
5398
5399                 test_commitment!("3044022009b048187705a8cbc9ad73adbe5af148c3d012e1f067961486c822c7af08158c022006d66f3704cfab3eb2dc49dae24e4aa22a6910fc9b424007583204e3621af2e5",
5400                                  "304402206fc2d1f10ea59951eefac0b4b7c396a3c3d87b71ff0b019796ef4535beaf36f902201765b0181e514d04f4c8ad75659d7037be26cdb3f8bb6f78fe61decef484c3ea",
5401                                  "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", {
5402
5403                                   { 0,
5404                                   "3045022100d9e29616b8f3959f1d3d7f7ce893ffedcdc407717d0de8e37d808c91d3a7c50d022078c3033f6d00095c8720a4bc943c1b45727818c082e4e3ddbc6d3116435b624b",
5405                                   "30440220636de5682ef0c5b61f124ec74e8aa2461a69777521d6998295dcea36bc3338110220165285594b23c50b28b82df200234566628a27bcd17f7f14404bd865354eb3ce",
5406                                   "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" },
5407
5408                                   { 1,
5409                                   "30440220649fe8b20e67e46cbb0d09b4acea87dbec001b39b08dee7bdd0b1f03922a8640022037c462dff79df501cecfdb12ea7f4de91f99230bb544726f6e04527b1f896004",
5410                                   "3045022100803159dee7935dba4a1d36a61055ce8fd62caa528573cc221ae288515405a252022029c59e7cffce374fe860100a4a63787e105c3cf5156d40b12dd53ff55ac8cf3f",
5411                                   "02000000000101ab84ff284f162cfbfef241f853b47d4368d171f9e2a1445160cd591c4c7d882b01000000000000000001d0070000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e05004730440220649fe8b20e67e46cbb0d09b4acea87dbec001b39b08dee7bdd0b1f03922a8640022037c462dff79df501cecfdb12ea7f4de91f99230bb544726f6e04527b1f89600401483045022100803159dee7935dba4a1d36a61055ce8fd62caa528573cc221ae288515405a252022029c59e7cffce374fe860100a4a63787e105c3cf5156d40b12dd53ff55ac8cf3f01008576a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c820120876475527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae67a914b43e1b38138a41b37f7cd9a1d274bc63e3a9b5d188ac6868f6010000" },
5412
5413                                   { 2,
5414                                   "30440220770fc321e97a19f38985f2e7732dd9fe08d16a2efa4bcbc0429400a447faf49102204d40b417f3113e1b0944ae0986f517564ab4acd3d190503faf97a6e420d43352",
5415                                   "3045022100a437cc2ce77400ecde441b3398fea3c3ad8bdad8132be818227fe3c5b8345989022069d45e7fa0ae551ec37240845e2c561ceb2567eacf3076a6a43a502d05865faa",
5416                                   "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" },
5417
5418                                   { 3,
5419                                   "304402207bcbf4f60a9829b05d2dbab84ed593e0291836be715dc7db6b72a64caf646af802201e489a5a84f7c5cc130398b841d138d031a5137ac8f4c49c770a4959dc3c1363",
5420                                   "304402203121d9b9c055f354304b016a36662ee99e1110d9501cb271b087ddb6f382c2c80220549882f3f3b78d9c492de47543cb9a697cecc493174726146536c5954dac7487",
5421                                   "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" },
5422
5423                                   { 4,
5424                                   "3044022076dca5cb81ba7e466e349b7128cdba216d4d01659e29b96025b9524aaf0d1899022060de85697b88b21c749702b7d2cfa7dfeaa1f472c8f1d7d9c23f2bf968464b87",
5425                                   "3045022100d9080f103cc92bac15ec42464a95f070c7fb6925014e673ee2ea1374d36a7f7502200c65294d22eb20d48564954d5afe04a385551919d8b2ddb4ae2459daaeee1d95",
5426                                   "02000000000101ab84ff284f162cfbfef241f853b47d4368d171f9e2a1445160cd591c4c7d882b04000000000000000001a00f0000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e0500473044022076dca5cb81ba7e466e349b7128cdba216d4d01659e29b96025b9524aaf0d1899022060de85697b88b21c749702b7d2cfa7dfeaa1f472c8f1d7d9c23f2bf968464b8701483045022100d9080f103cc92bac15ec42464a95f070c7fb6925014e673ee2ea1374d36a7f7502200c65294d22eb20d48564954d5afe04a385551919d8b2ddb4ae2459daaeee1d95012004040404040404040404040404040404040404040404040404040404040404048a76a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c8201208763a91418bc1a114ccf9c052d3d23e28d3b0a9d1227434288527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae677502f801b175ac686800000000" }
5427                 } );
5428
5429                 // commitment tx with seven outputs untrimmed (maximum feerate)
5430                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5431                 chan.feerate_per_kw = 647;
5432
5433                 test_commitment!("3045022100a135f9e8a5ed25f7277446c67956b00ce6f610ead2bdec2c2f686155b7814772022059f1f6e1a8b336a68efcc1af3fe4d422d4827332b5b067501b099c47b7b5b5ee",
5434                                  "30450221009ec15c687898bb4da8b3a833e5ab8bfc51ec6e9202aaa8e66611edfd4a85ed1102203d7183e45078b9735c93450bc3415d3e5a8c576141a711ec6ddcb4a893926bb7",
5435                                  "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", {
5436
5437                                   { 0,
5438                                   "30450221008437627f9ad84ac67052e2a414a4367b8556fd1f94d8b02590f89f50525cd33502205b9c21ff6e7fc864f2352746ad8ba59182510819acb644e25b8a12fc37bbf24f",
5439                                   "30440220344b0deb055230d01703e6c7acd45853c4af2328b49b5d8af4f88a060733406602202ea64f2a43d5751edfe75503cbc35a62e3141b5ed032fa03360faf4ca66f670b",
5440                                   "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" },
5441
5442                                   { 1,
5443                                   "304402205a67f92bf6845cf2892b48d874ac1daf88a36495cf8a06f93d83180d930a6f75022031da1621d95c3f335cc06a3056cf960199dae600b7cf89088f65fc53cdbef28c",
5444                                   "30450221009e5e3822b0185c6799a95288c597b671d6cc69ab80f43740f00c6c3d0752bdda02206da947a74bd98f3175324dc56fdba86cc783703a120a6f0297537e60632f4c7f",
5445                                   "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" },
5446
5447                                   { 2,
5448                                   "30440220437e21766054a3eef7f65690c5bcfa9920babbc5af92b819f772f6ea96df6c7402207173622024bd97328cfb26c6665e25c2f5d67c319443ccdc60c903217005d8c8",
5449                                   "3045022100fcfc47e36b712624677626cef3dc1d67f6583bd46926a6398fe6b00b0c9a37760220525788257b187fc775c6370d04eadf34d06f3650a63f8df851cee0ecb47a1673",
5450                                   "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" },
5451
5452                                   { 3,
5453                                   "304402207436e10737e4df499fc051686d3e11a5bb2310e4d1f1e691d287cef66514791202207cb58e71a6b7a42dd001b7e3ae672ea4f71ea3e1cd412b742e9124abb0739c64",
5454                                   "3045022100e78211b8409afb7255ffe37337da87f38646f1faebbdd61bc1920d69e3ead67a02201a626305adfcd16bfb7e9340928d9b6305464eab4aa4c4a3af6646e9b9f69dee",
5455                                   "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" },
5456
5457                                   { 4,
5458                                   "30450221009acd6a827a76bfee50806178dfe0495cd4e1d9c58279c194c7b01520fe68cb8d022024d439047c368883e570997a7d40f0b430cb5a742f507965e7d3063ae3feccca",
5459                                   "3044022048762cf546bbfe474f1536365ea7c416e3c0389d60558bc9412cb148fb6ab68202207215d7083b75c96ff9d2b08c59c34e287b66820f530b486a9aa4cdd9c347d5b9",
5460                                   "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" }
5461                 } );
5462
5463                 // commitment tx with six outputs untrimmed (minimum feerate)
5464                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5465                 chan.feerate_per_kw = 648;
5466
5467                 test_commitment!("304402203948f900a5506b8de36a4d8502f94f21dd84fd9c2314ab427d52feaa7a0a19f2022059b6a37a4adaa2c5419dc8aea63c6e2a2ec4c4bde46207f6dc1fcd22152fc6e5",
5468                                  "3045022100b15f72908ba3382a34ca5b32519240a22300cc6015b6f9418635fb41f3d01d8802207adb331b9ed1575383dca0f2355e86c173802feecf8298fbea53b9d4610583e9",
5469                                  "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", {
5470
5471                                   { 0,
5472                                   "3045022100a031202f3be94678f0e998622ee95ebb6ada8da1e9a5110228b5e04a747351e4022010ca6a21e18314ed53cfaae3b1f51998552a61a468e596368829a50ce40110e0",
5473                                   "304502210097e1873b57267730154595187a34949d3744f52933070c74757005e61ce2112e02204ecfba2aa42d4f14bdf8bad4206bb97217b702e6c433e0e1b0ce6587e6d46ec6",
5474                                   "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" },
5475
5476                                   { 1,
5477                                   "304402202361012a634aee7835c5ecdd6413dcffa8f404b7e77364c792cff984e4ee71e90220715c5e90baa08daa45a7439b1ee4fa4843ed77b19c058240b69406606d384124",
5478                                   "3044022019de73b00f1d818fb388e83b2c8c31f6bce35ac624e215bc12f88f9dc33edf48022006ff814bb9f700ee6abc3294e146fac3efd4f13f0005236b41c0a946ee00c9ae",
5479                                   "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" },
5480
5481                                   { 2,
5482                                   "304402207e8e82cd71ed4febeb593732c260456836e97d81896153ecd2b3cf320ca6861702202dd4a30f68f98ced7cc56a36369ac1fdd978248c5ff4ed204fc00cc625532989",
5483                                   "3045022100bd0be6100c4fd8f102ec220e1b053e4c4e2ecca25615490150007b40d314dc3902201a1e0ea266965b43164d9e6576f58fa6726d42883dd1c3996d2925c2e2260796",
5484                                   "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" },
5485
5486                                   { 3,
5487                                   "3044022024cd52e4198c8ae0e414a86d86b5a65ea7450f2eb4e783096736d93395eca5ce022078f0094745b45be4d4b2b04dd5978c9e66ba49109e5704403e84aaf5f387d6be",
5488                                   "3045022100bbfb9d0a946d420807c86e985d636cceb16e71c3694ed186316251a00cbd807202207773223f9a337e145f64673825be9b30d07ef1542c82188b264bedcf7cda78c6",
5489                                   "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" }
5490                 } );
5491
5492                 // commitment tx with six outputs untrimmed (maximum feerate)
5493                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5494                 chan.feerate_per_kw = 2069;
5495
5496                 test_commitment!("304502210090b96a2498ce0c0f2fadbec2aab278fed54c1a7838df793ec4d2c78d96ec096202204fdd439c50f90d483baa7b68feeef4bd33bc277695405447bcd0bfb2ca34d7bc",
5497                                  "3045022100ad9a9bbbb75d506ca3b716b336ee3cf975dd7834fcf129d7dd188146eb58a8b4022061a759ee417339f7fe2ea1e8deb83abb6a74db31a09b7648a932a639cda23e33",
5498                                  "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", {
5499
5500                                   { 0,
5501                                   "3045022100f33513ee38abf1c582876f921f8fddc06acff48e04515532a32d3938de938ffd02203aa308a2c1863b7d6fdf53159a1465bf2e115c13152546cc5d74483ceaa7f699",
5502                                   "3045022100a637902a5d4c9ba9e7c472a225337d5aac9e2e3f6744f76e237132e7619ba0400220035c60d784a031c0d9f6df66b7eab8726a5c25397399ee4aa960842059eb3f9d",
5503                                   "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" },
5504
5505                                   { 1,
5506                                   "3045022100ce07682cf4b90093c22dc2d9ab2a77ad6803526b655ef857221cc96af5c9e0bf02200f501cee22e7a268af40b555d15a8237c9f36ad67ef1841daf9f6a0267b1e6df",
5507                                   "3045022100e57e46234f8782d3ff7aa593b4f7446fb5316c842e693dc63ee324fd49f6a1c302204a2f7b44c48bd26e1554422afae13153eb94b29d3687b733d18930615fb2db61",
5508                                   "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" },
5509
5510                                   { 2,
5511                                   "3045022100e3e35492e55f82ec0bc2f317ffd7a486d1f7024330fe9743c3559fc39f32ef0c02203d1d4db651fc388a91d5ad8ecdd8e83673063bc8eefe27cfd8c189090e3a23e0",
5512                                   "3044022068613fb1b98eb3aec7f44c5b115b12343c2f066c4277c82b5f873dfe68f37f50022028109b4650f3f528ca4bfe9a467aff2e3e43893b61b5159157119d5d95cf1c18",
5513                                   "02000000000101adbe717a63fb658add30ada1e6e12ed257637581898abe475c11d7bbcd65bd4d020000000000000000015d060000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e0500483045022100e3e35492e55f82ec0bc2f317ffd7a486d1f7024330fe9743c3559fc39f32ef0c02203d1d4db651fc388a91d5ad8ecdd8e83673063bc8eefe27cfd8c189090e3a23e001473044022068613fb1b98eb3aec7f44c5b115b12343c2f066c4277c82b5f873dfe68f37f50022028109b4650f3f528ca4bfe9a467aff2e3e43893b61b5159157119d5d95cf1c1801008576a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c820120876475527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae67a9148a486ff2e31d6158bf39e2608864d63fefd09d5b88ac6868f7010000" },
5514
5515                                   { 3,
5516                                   "304402207475aeb0212ef9bf5130b60937817ad88c9a87976988ef1f323f026148cc4a850220739fea17ad3257dcad72e509c73eebe86bee30b178467b9fdab213d631b109df",
5517                                   "3045022100d315522e09e7d53d2a659a79cb67fef56d6c4bddf3f46df6772d0d20a7beb7c8022070bcc17e288607b6a72be0bd83368bb6d53488db266c1cdb4d72214e4f02ac33",
5518                                   "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" }
5519                 } );
5520
5521                 // commitment tx with five outputs untrimmed (minimum feerate)
5522                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5523                 chan.feerate_per_kw = 2070;
5524
5525                 test_commitment!("304402204ca1ba260dee913d318271d86e10ca0f5883026fb5653155cff600fb40895223022037b145204b7054a40e08bb1fefbd826f827b40838d3e501423bcc57924bcb50c",
5526                                  "3044022001014419b5ba00e083ac4e0a85f19afc848aacac2d483b4b525d15e2ae5adbfe022015ebddad6ee1e72b47cb09f3e78459da5be01ccccd95dceca0e056a00cc773c1",
5527                                  "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", {
5528
5529                                   { 0,
5530                                   "304402205f6b6d12d8d2529fb24f4445630566cf4abbd0f9330ab6c2bdb94222d6a2a0c502202f556258ae6f05b193749e4c541dfcc13b525a5422f6291f073f15617ba8579b",
5531                                   "30440220150b11069454da70caf2492ded9e0065c9a57f25ac2a4c52657b1d15b6c6ed85022068a38833b603c8892717206383611bad210f1cbb4b1f87ea29c6c65b9e1cb3e5",
5532                                   "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" },
5533
5534                                   { 1,
5535                                   "3045022100f960dfb1c9aee7ce1437efa65b523e399383e8149790e05d8fed27ff6e42fe0002202fe8613e062ffe0b0c518cc4101fba1c6de70f64a5bcc7ae663f2efae43b8546",
5536                                   "30450221009a6ed18e6873bc3644332a6ee21c152a5b102821865350df7a8c74451a51f9f2022050d801fb4895d7d7fbf452824c0168347f5c0cbe821cf6a97a63af5b8b2563c6",
5537                                   "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" },
5538
5539                                   { 2,
5540                                   "3045022100ae5fc7717ae684bc1fcf9020854e5dbe9842c9e7472879ac06ff95ac2bb10e4e022057728ada4c00083a3e65493fb5d50a232165948a1a0f530ef63185c2c8c56504",
5541                                   "30440220408ad3009827a8fccf774cb285587686bfb2ed041f89a89453c311ce9c8ee0f902203c7392d9f8306d3a46522a66bd2723a7eb2628cb2d9b34d4c104f1766bf37502",
5542                                   "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" }
5543                 } );
5544
5545                 // commitment tx with five outputs untrimmed (maximum feerate)
5546                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5547                 chan.feerate_per_kw = 2194;
5548
5549                 test_commitment!("304402204bb3d6e279d71d9da414c82de42f1f954267c762b2e2eb8b76bc3be4ea07d4b0022014febc009c5edc8c3fc5d94015de163200f780046f1c293bfed8568f08b70fb3",
5550                                  "3044022072c2e2b1c899b2242656a537dde2892fa3801be0d6df0a87836c550137acde8302201654aa1974d37a829083c3ba15088689f30b56d6a4f6cb14c7bad0ee3116d398",
5551                                  "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", {
5552
5553                                   { 0,
5554                                   "3045022100939726680351a7856c1bc386d4a1f422c7d29bd7b56afc139570f508474e6c40022023175a799ccf44c017fbaadb924c40b2a12115a5b7d0dfd3228df803a2de8450",
5555                                   "304502210099c98c2edeeee6ec0fb5f3bea8b79bb016a2717afa9b5072370f34382de281d302206f5e2980a995e045cf90a547f0752a7ee99d48547bc135258fe7bc07e0154301",
5556                                   "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" },
5557
5558                                   { 1,
5559                                   "3044022021bb883bf324553d085ba2e821cad80c28ef8b303dbead8f98e548783c02d1600220638f9ef2a9bba25869afc923f4b5dc38be3bb459f9efa5d869392d5f7779a4a0",
5560                                   "3045022100fd85bd7697b89c08ec12acc8ba89b23090637d83abd26ca37e01ae93e67c367302202b551fe69386116c47f984aab9c8dfd25d864dcde5d3389cfbef2447a85c4b77",
5561                                   "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" },
5562
5563                                   { 2,
5564                                   "3045022100c9e6f0454aa598b905a35e641a70cc9f67b5f38cc4b00843a041238c4a9f1c4a0220260a2822a62da97e44583e837245995ca2e36781769c52f19e498efbdcca262b",
5565                                   "30450221008a9f2ea24cd455c2b64c1472a5fa83865b0a5f49a62b661801e884cf2849af8302204d44180e50bf6adfcf1c1e581d75af91aba4e28681ce4a5ee5f3cbf65eca10f3",
5566                                   "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" }
5567                 } );
5568
5569                 // commitment tx with four outputs untrimmed (minimum feerate)
5570                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5571                 chan.feerate_per_kw = 2195;
5572
5573                 test_commitment!("304402201a8c1b1f9671cd9e46c7323a104d7047cc48d3ee80d40d4512e0c72b8dc65666022066d7f9a2ce18c9eb22d2739ffcce05721c767f9b607622a31b6ea5793ddce403",
5574                                  "3044022044d592025b610c0d678f65032e87035cdfe89d1598c522cc32524ae8172417c30220749fef9d5b2ae8cdd91ece442ba8809bc891efedae2291e578475f97715d1767",
5575                                  "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", {
5576
5577                                   { 0,
5578                                   "3045022100e57b845066a06ee7c2cbfc29eabffe52daa9bf6f6de760066d04df9f9b250e0002202ffb197f0e6e0a77a75a9aff27014bd3de83b7f748d7efef986abe655e1dd50e",
5579                                   "3045022100ecc8c6529d0b2316d046f0f0757c1e1c25a636db168ec4f3aa1b9278df685dc0022067ae6b65e936f1337091f7b18a15935b608c5f2cdddb2f892ed0babfdd376d76",
5580                                   "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" },
5581
5582                                   { 1,
5583                                   "3045022100d193b7ecccad8057571620a0b1ffa6c48e9483311723b59cf536043b20bc51550220546d4bd37b3b101ecda14f6c907af46ec391abce1cd9c7ce22b1a62b534f2f2a",
5584                                   "3044022014d66f11f9cacf923807eba49542076c5fe5cccf252fb08fe98c78ef3ca6ab5402201b290dbe043cc512d9d78de074a5a129b8759bc6a6c546b190d120b690bd6e82",
5585                                   "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" }
5586                 } );
5587
5588                 // commitment tx with four outputs untrimmed (maximum feerate)
5589                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5590                 chan.feerate_per_kw = 3702;
5591
5592                 test_commitment!("304502210092a587aeb777f869e7ff0d7898ea619ee26a3dacd1f3672b945eea600be431100220077ee9eae3528d15251f2a52b607b189820e57a6ccfac8d1af502b132ee40169",
5593                                  "3045022100e5efb73c32d32da2d79702299b6317de6fb24a60476e3855926d78484dd1b3c802203557cb66a42c944ef06e00bcc4da35a5bcb2f185aab0f8e403e519e1d66aaf75",
5594                                  "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", {
5595
5596                                   { 0,
5597                                   "304402206fa54c11f98c3bae1e93df43fc7affeb05b476bf8060c03e29c377c69bc08e8b0220672701cce50d5c379ff45a5d2cfe48ac44973adb066ac32608e21221d869bb89",
5598                                   "304402206e36c683ebf2cb16bcef3d5439cf8b53cd97280a365ed8acd7abb85a8ba5f21c02206e8621edfc2a5766cbc96eb67fd501127ff163eb6b85518a39f7d4974aef126f",
5599                                   "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" },
5600
5601                                   { 1,
5602                                   "3044022057649739b0eb74d541ead0dfdb3d4b2c15aa192720031044c3434c67812e5ca902201e5ede42d960ae551707f4a6b34b09393cf4dee2418507daa022e3550dbb5817",
5603                                   "304402207faad26678c8850e01b4a0696d60841f7305e1832b786110ee9075cb92ed14a30220516ef8ee5dfa80824ea28cbcec0dd95f8b847146257c16960db98507db15ffdc",
5604                                   "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" }
5605                 } );
5606
5607                 // commitment tx with three outputs untrimmed (minimum feerate)
5608                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5609                 chan.feerate_per_kw = 3703;
5610
5611                 test_commitment!("3045022100b495d239772a237ff2cf354b1b11be152fd852704cb184e7356d13f2fb1e5e430220723db5cdb9cbd6ead7bfd3deb419cf41053a932418cbb22a67b581f40bc1f13e",
5612                                  "304402201b736d1773a124c745586217a75bed5f66c05716fbe8c7db4fdb3c3069741cdd02205083f39c321c1bcadfc8d97e3c791a66273d936abac0c6a2fde2ed46019508e1",
5613                                  "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", {
5614
5615                                   { 0,
5616                                   "3045022100c34c61735f93f2e324cc873c3b248111ccf8f6db15d5969583757010d4ad2b4602207867bb919b2ddd6387873e425345c9b7fd18d1d66aba41f3607bc2896ef3c30a",
5617                                   "3045022100988c143e2110067117d2321bdd4bd16ca1734c98b29290d129384af0962b634e02206c1b02478878c5f547018b833986578f90c3e9be669fe5788ad0072a55acbb05",
5618                                   "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" }
5619                 } );
5620
5621                 // commitment tx with three outputs untrimmed (maximum feerate)
5622                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5623                 chan.feerate_per_kw = 4914;
5624
5625                 test_commitment!("3045022100b4b16d5f8cc9fc4c1aff48831e832a0d8990e133978a66e302c133550954a44d022073573ce127e2200d316f6b612803a5c0c97b8d20e1e44dbe2ac0dd2fb8c95244",
5626                                  "3045022100d72638bc6308b88bb6d45861aae83e5b9ff6e10986546e13bce769c70036e2620220320be7c6d66d22f30b9fcd52af66531505b1310ca3b848c19285b38d8a1a8c19",
5627                                  "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", {
5628
5629                                   { 0,
5630                                   "3045022100f43591c156038ba217756006bb3c55f7d113a325cdd7d9303c82115372858d68022016355b5aadf222bc8d12e426c75f4a03423917b2443a103eb2a498a3a2234374",
5631                                   "30440220585dee80fafa264beac535c3c0bb5838ac348b156fdc982f86adc08dfc9bfd250220130abb82f9f295cc9ef423dcfef772fde2acd85d9df48cc538981d26a10a9c10",
5632                                   "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" }
5633                 } );
5634
5635                 // commitment tx with two outputs untrimmed (minimum feerate)
5636                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5637                 chan.feerate_per_kw = 4915;
5638
5639                 test_commitment!("304402203a286936e74870ca1459c700c71202af0381910a6bfab687ef494ef1bc3e02c902202506c362d0e3bee15e802aa729bf378e051644648253513f1c085b264cc2a720",
5640                                  "30450221008a953551f4d67cb4df3037207fc082ddaf6be84d417b0bd14c80aab66f1b01a402207508796dc75034b2dee876fe01dc05a08b019f3e5d689ac8842ade2f1befccf5",
5641                                  "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", {});
5642
5643                 // commitment tx with two outputs untrimmed (maximum feerate)
5644                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5645                 chan.feerate_per_kw = 9651180;
5646
5647                 test_commitment!("304402200a8544eba1d216f5c5e530597665fa9bec56943c0f66d98fc3d028df52d84f7002201e45fa5c6bc3a506cc2553e7d1c0043a9811313fc39c954692c0d47cfce2bbd3",
5648                                  "3045022100e11b638c05c650c2f63a421d36ef8756c5ce82f2184278643520311cdf50aa200220259565fb9c8e4a87ccaf17f27a3b9ca4f20625754a0920d9c6c239d8156a11de",
5649                                  "02000000000101bef67e4e2fb9ddeeb3461973cd4c62abb35050b1add772995b820b584a488489000000000038b02b800222020000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80ec0c62d0000000000160014cc1b07838e387deacd0e5232e1e8b49f4c29e4840400483045022100e11b638c05c650c2f63a421d36ef8756c5ce82f2184278643520311cdf50aa200220259565fb9c8e4a87ccaf17f27a3b9ca4f20625754a0920d9c6c239d8156a11de0147304402200a8544eba1d216f5c5e530597665fa9bec56943c0f66d98fc3d028df52d84f7002201e45fa5c6bc3a506cc2553e7d1c0043a9811313fc39c954692c0d47cfce2bbd301475221023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb21030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c152ae3e195220", {});
5650
5651                 // commitment tx with one output untrimmed (minimum feerate)
5652                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5653                 chan.feerate_per_kw = 9651181;
5654
5655                 test_commitment!("304402202ade0142008309eb376736575ad58d03e5b115499709c6db0b46e36ff394b492022037b63d78d66404d6504d4c4ac13be346f3d1802928a6d3ad95a6a944227161a2",
5656                                  "304402207e8d51e0c570a5868a78414f4e0cbfaed1106b171b9581542c30718ee4eb95ba02203af84194c97adf98898c9afe2f2ed4a7f8dba05a2dfab28ac9d9c604aa49a379",
5657                                  "02000000000101bef67e4e2fb9ddeeb3461973cd4c62abb35050b1add772995b820b584a488489000000000038b02b8001c0c62d0000000000160014cc1b07838e387deacd0e5232e1e8b49f4c29e484040047304402207e8d51e0c570a5868a78414f4e0cbfaed1106b171b9581542c30718ee4eb95ba02203af84194c97adf98898c9afe2f2ed4a7f8dba05a2dfab28ac9d9c604aa49a3790147304402202ade0142008309eb376736575ad58d03e5b115499709c6db0b46e36ff394b492022037b63d78d66404d6504d4c4ac13be346f3d1802928a6d3ad95a6a944227161a201475221023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb21030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c152ae3e195220", {});
5658
5659                 // commitment tx with fee greater than funder amount
5660                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5661                 chan.feerate_per_kw = 9651936;
5662
5663                 test_commitment!("304402202ade0142008309eb376736575ad58d03e5b115499709c6db0b46e36ff394b492022037b63d78d66404d6504d4c4ac13be346f3d1802928a6d3ad95a6a944227161a2",
5664                                  "304402207e8d51e0c570a5868a78414f4e0cbfaed1106b171b9581542c30718ee4eb95ba02203af84194c97adf98898c9afe2f2ed4a7f8dba05a2dfab28ac9d9c604aa49a379",
5665                                  "02000000000101bef67e4e2fb9ddeeb3461973cd4c62abb35050b1add772995b820b584a488489000000000038b02b8001c0c62d0000000000160014cc1b07838e387deacd0e5232e1e8b49f4c29e484040047304402207e8d51e0c570a5868a78414f4e0cbfaed1106b171b9581542c30718ee4eb95ba02203af84194c97adf98898c9afe2f2ed4a7f8dba05a2dfab28ac9d9c604aa49a3790147304402202ade0142008309eb376736575ad58d03e5b115499709c6db0b46e36ff394b492022037b63d78d66404d6504d4c4ac13be346f3d1802928a6d3ad95a6a944227161a201475221023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb21030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c152ae3e195220", {});
5666
5667                 // commitment tx with 3 htlc outputs, 2 offered having the same amount and preimage
5668                 chan.value_to_self_msat = 7_000_000_000 - 2_000_000;
5669                 chan.feerate_per_kw = 253;
5670                 chan.pending_inbound_htlcs.clear();
5671                 chan.pending_inbound_htlcs.push({
5672                         let mut out = InboundHTLCOutput{
5673                                 htlc_id: 1,
5674                                 amount_msat: 2000000,
5675                                 cltv_expiry: 501,
5676                                 payment_hash: PaymentHash([0; 32]),
5677                                 state: InboundHTLCState::Committed,
5678                         };
5679                         out.payment_hash.0 = Sha256::hash(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()).into_inner();
5680                         out
5681                 });
5682                 chan.pending_outbound_htlcs.clear();
5683                 chan.pending_outbound_htlcs.push({
5684                         let mut out = OutboundHTLCOutput{
5685                                 htlc_id: 6,
5686                                 amount_msat: 5000000,
5687                                 cltv_expiry: 506,
5688                                 payment_hash: PaymentHash([0; 32]),
5689                                 state: OutboundHTLCState::Committed,
5690                                 source: HTLCSource::dummy(),
5691                         };
5692                         out.payment_hash.0 = Sha256::hash(&hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()).into_inner();
5693                         out
5694                 });
5695                 chan.pending_outbound_htlcs.push({
5696                         let mut out = OutboundHTLCOutput{
5697                                 htlc_id: 5,
5698                                 amount_msat: 5000000,
5699                                 cltv_expiry: 505,
5700                                 payment_hash: PaymentHash([0; 32]),
5701                                 state: OutboundHTLCState::Committed,
5702                                 source: HTLCSource::dummy(),
5703                         };
5704                         out.payment_hash.0 = Sha256::hash(&hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()).into_inner();
5705                         out
5706                 });
5707
5708                 test_commitment!("30440220048705bec5288d28b3f29344b8d124853b1af423a568664d2c6f02c8ea886525022060f998a461052a2476b912db426ea2a06700953a241135c7957f2e79bc222df9",
5709                                  "3045022100c4f1d60b6fca9febc8b39de1a31e84c5f7c4b41c97239ef05f4350aa484c6b5e02200c5134ac8b20eb7a29d0dd4a501f6aa8fefb8489171f4cb408bd2a32324ab03f",
5710                                  "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", {
5711
5712                                   { 0,
5713                                   "304502210081cbb94121761d34c189cd4e6a281feea6f585060ad0ba2632e8d6b3c6bb8a6c02201007981bbd16539d63df2805b5568f1f5688cd2a885d04706f50db9b77ba13c6",
5714                                   "304502210090ed76aeb21b53236a598968abc66e2024691d07b62f53ddbeca8f93144af9c602205f873af5a0c10e62690e9aba09740550f194a9dc455ba4c1c23f6cde7704674c",
5715                                   "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" },
5716                                   { 1,
5717                                   "304402201d0f09d2bf7bc245a4f17980e1e9164290df16c70c6a2ff1592f5030d6108581022061e744a7dc151b36bf0aff7a4f1812ba90b8b03633bb979a270d19858fd960c5",
5718                                   "30450221009aef000d2e843a4202c1b1a2bf554abc9a7902bf49b2cb0759bc507456b7ebad02204e7c3d193ede2fd2b4cd6b39f51a920e581e35575e357e44d7b699c40ce61d39",
5719                                   "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" },
5720                                   { 2,
5721                                   "30440220010bf035d5823596e50dce2076a4d9f942d8d28031c9c428b901a02b6b8140de02203250e8e4a08bc5b4ecdca4d0eedf98223e02e3ac1c0206b3a7ffdb374aa21e5f",
5722                                   "30440220073de0067b88e425b3018b30366bfeda0ccb703118ccd3d02ead08c0f53511d002203fac50ac0e4cf8a3af0b4b1b12e801650591f748f8ddf1e089c160f10b69e511",
5723                                   "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" }
5724                 } );
5725         }
5726
5727         #[test]
5728         fn test_per_commitment_secret_gen() {
5729                 // Test vectors from BOLT 3 Appendix D:
5730
5731                 let mut seed = [0; 32];
5732                 seed[0..32].clone_from_slice(&hex::decode("0000000000000000000000000000000000000000000000000000000000000000").unwrap());
5733                 assert_eq!(chan_utils::build_commitment_secret(&seed, 281474976710655),
5734                            hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap()[..]);
5735
5736                 seed[0..32].clone_from_slice(&hex::decode("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF").unwrap());
5737                 assert_eq!(chan_utils::build_commitment_secret(&seed, 281474976710655),
5738                            hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap()[..]);
5739
5740                 assert_eq!(chan_utils::build_commitment_secret(&seed, 0xaaaaaaaaaaa),
5741                            hex::decode("56f4008fb007ca9acf0e15b054d5c9fd12ee06cea347914ddbaed70d1c13a528").unwrap()[..]);
5742
5743                 assert_eq!(chan_utils::build_commitment_secret(&seed, 0x555555555555),
5744                            hex::decode("9015daaeb06dba4ccc05b91b2f73bd54405f2be9f217fbacd3c5ac2e62327d31").unwrap()[..]);
5745
5746                 seed[0..32].clone_from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap());
5747                 assert_eq!(chan_utils::build_commitment_secret(&seed, 1),
5748                            hex::decode("915c75942a26bb3a433a8ce2cb0427c29ec6c1775cfc78328b57f6ba7bfeaa9c").unwrap()[..]);
5749         }
5750
5751         #[test]
5752         fn test_key_derivation() {
5753                 // Test vectors from BOLT 3 Appendix E:
5754                 let secp_ctx = Secp256k1::new();
5755
5756                 let base_secret = SecretKey::from_slice(&hex::decode("000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f").unwrap()[..]).unwrap();
5757                 let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
5758
5759                 let base_point = PublicKey::from_secret_key(&secp_ctx, &base_secret);
5760                 assert_eq!(base_point.serialize()[..], hex::decode("036d6caac248af96f6afa7f904f550253a0f3ef3f5aa2fe6838a95b216691468e2").unwrap()[..]);
5761
5762                 let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
5763                 assert_eq!(per_commitment_point.serialize()[..], hex::decode("025f7117a78150fe2ef97db7cfc83bd57b2e2c0d0dd25eaf467a4a1c2a45ce1486").unwrap()[..]);
5764
5765                 assert_eq!(chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &base_point).unwrap().serialize()[..],
5766                                 hex::decode("0235f2dbfaa89b57ec7b055afe29849ef7ddfeb1cefdb9ebdc43f5494984db29e5").unwrap()[..]);
5767
5768                 assert_eq!(chan_utils::derive_private_key(&secp_ctx, &per_commitment_point, &base_secret).unwrap(),
5769                                 SecretKey::from_slice(&hex::decode("cbced912d3b21bf196a766651e436aff192362621ce317704ea2f75d87e7be0f").unwrap()[..]).unwrap());
5770
5771                 assert_eq!(chan_utils::derive_public_revocation_key(&secp_ctx, &per_commitment_point, &base_point).unwrap().serialize()[..],
5772                                 hex::decode("02916e326636d19c33f13e8c0c3a03dd157f332f3e99c317c141dd865eb01f8ff0").unwrap()[..]);
5773
5774                 assert_eq!(chan_utils::derive_private_revocation_key(&secp_ctx, &per_commitment_secret, &base_secret).unwrap(),
5775                                 SecretKey::from_slice(&hex::decode("d09ffff62ddb2297ab000cc85bcb4283fdeb6aa052affbc9dddcf33b61078110").unwrap()[..]).unwrap());
5776         }
5777 }