Use core replacements for std members
[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 core::{cmp,mem,fmt};
43 use core::ops::Deref;
44 #[cfg(any(test, feature = "fuzztarget"))]
45 use std::sync::Mutex;
46 use bitcoin::hashes::hex::ToHex;
47 use bitcoin::blockdata::opcodes::all::OP_PUSHBYTES_0;
48
49 #[cfg(test)]
50 pub struct ChannelValueStat {
51         pub value_to_self_msat: u64,
52         pub channel_value_msat: u64,
53         pub channel_reserve_msat: u64,
54         pub pending_outbound_htlcs_amount_msat: u64,
55         pub pending_inbound_htlcs_amount_msat: u64,
56         pub holding_cell_outbound_amount_msat: u64,
57         pub counterparty_max_htlc_value_in_flight_msat: u64, // outgoing
58         pub counterparty_dust_limit_msat: u64,
59 }
60
61 enum InboundHTLCRemovalReason {
62         FailRelay(msgs::OnionErrorPacket),
63         FailMalformed(([u8; 32], u16)),
64         Fulfill(PaymentPreimage),
65 }
66
67 enum InboundHTLCState {
68         /// Offered by remote, to be included in next local commitment tx. I.e., the remote sent an
69         /// update_add_htlc message for this HTLC.
70         RemoteAnnounced(PendingHTLCStatus),
71         /// Included in a received commitment_signed message (implying we've
72         /// revoke_and_ack'd it), but the remote hasn't yet revoked their previous
73         /// state (see the example below). We have not yet included this HTLC in a
74         /// commitment_signed message because we are waiting on the remote's
75         /// aforementioned state revocation. One reason this missing remote RAA
76         /// (revoke_and_ack) blocks us from constructing a commitment_signed message
77         /// is because every time we create a new "state", i.e. every time we sign a
78         /// new commitment tx (see [BOLT #2]), we need a new per_commitment_point,
79         /// which are provided one-at-a-time in each RAA. E.g., the last RAA they
80         /// sent provided the per_commitment_point for our current commitment tx.
81         /// The other reason we should not send a commitment_signed without their RAA
82         /// is because their RAA serves to ACK our previous commitment_signed.
83         ///
84         /// Here's an example of how an HTLC could come to be in this state:
85         /// remote --> update_add_htlc(prev_htlc)   --> local
86         /// remote --> commitment_signed(prev_htlc) --> local
87         /// remote <-- revoke_and_ack               <-- local
88         /// remote <-- commitment_signed(prev_htlc) <-- local
89         /// [note that here, the remote does not respond with a RAA]
90         /// remote --> update_add_htlc(this_htlc)   --> local
91         /// remote --> commitment_signed(prev_htlc, this_htlc) --> local
92         /// Now `this_htlc` will be assigned this state. It's unable to be officially
93         /// accepted, i.e. included in a commitment_signed, because we're missing the
94         /// RAA that provides our next per_commitment_point. The per_commitment_point
95         /// is used to derive commitment keys, which are used to construct the
96         /// signatures in a commitment_signed message.
97         /// Implies AwaitingRemoteRevoke.
98         ///
99         /// [BOLT #2]: https://github.com/lightningnetwork/lightning-rfc/blob/master/02-peer-protocol.md
100         AwaitingRemoteRevokeToAnnounce(PendingHTLCStatus),
101         /// Included in a received commitment_signed message (implying we've revoke_and_ack'd it).
102         /// We have also included this HTLC in our latest commitment_signed and are now just waiting
103         /// on the remote's revoke_and_ack to make this HTLC an irrevocable part of the state of the
104         /// channel (before it can then get forwarded and/or removed).
105         /// Implies AwaitingRemoteRevoke.
106         AwaitingAnnouncedRemoteRevoke(PendingHTLCStatus),
107         Committed,
108         /// Removed by us and a new commitment_signed was sent (if we were AwaitingRemoteRevoke when we
109         /// created it we would have put it in the holding cell instead). When they next revoke_and_ack
110         /// we'll drop it.
111         /// Note that we have to keep an eye on the HTLC until we've received a broadcastable
112         /// commitment transaction without it as otherwise we'll have to force-close the channel to
113         /// claim it before the timeout (obviously doesn't apply to revoked HTLCs that we can't claim
114         /// anyway). That said, ChannelMonitor does this for us (see
115         /// ChannelMonitor::would_broadcast_at_height) so we actually remove the HTLC from our own
116         /// local state before then, once we're sure that the next commitment_signed and
117         /// ChannelMonitor::provide_latest_local_commitment_tx will not include this HTLC.
118         LocalRemoved(InboundHTLCRemovalReason),
119 }
120
121 struct InboundHTLCOutput {
122         htlc_id: u64,
123         amount_msat: u64,
124         cltv_expiry: u32,
125         payment_hash: PaymentHash,
126         state: InboundHTLCState,
127 }
128
129 enum OutboundHTLCState {
130         /// Added by us and included in a commitment_signed (if we were AwaitingRemoteRevoke when we
131         /// created it we would have put it in the holding cell instead). When they next revoke_and_ack
132         /// we will promote to Committed (note that they may not accept it until the next time we
133         /// revoke, but we don't really care about that:
134         ///  * they've revoked, so worst case we can announce an old state and get our (option on)
135         ///    money back (though we won't), and,
136         ///  * we'll send them a revoke when they send a commitment_signed, and since only they're
137         ///    allowed to remove it, the "can only be removed once committed on both sides" requirement
138         ///    doesn't matter to us and it's up to them to enforce it, worst-case they jump ahead but
139         ///    we'll never get out of sync).
140         /// Note that we Box the OnionPacket as it's rather large and we don't want to blow up
141         /// OutboundHTLCOutput's size just for a temporary bit
142         LocalAnnounced(Box<msgs::OnionPacket>),
143         Committed,
144         /// Remote removed this (outbound) HTLC. We're waiting on their commitment_signed to finalize
145         /// the change (though they'll need to revoke before we fail the payment).
146         RemoteRemoved(Option<HTLCFailReason>),
147         /// Remote removed this and sent a commitment_signed (implying we've revoke_and_ack'ed it), but
148         /// the remote side hasn't yet revoked their previous state, which we need them to do before we
149         /// can do any backwards failing. Implies AwaitingRemoteRevoke.
150         /// We also have not yet removed this HTLC in a commitment_signed message, and are waiting on a
151         /// remote revoke_and_ack on a previous state before we can do so.
152         AwaitingRemoteRevokeToRemove(Option<HTLCFailReason>),
153         /// Remote removed this and sent a commitment_signed (implying we've revoke_and_ack'ed it), but
154         /// the remote side hasn't yet revoked their previous state, which we need them to do before we
155         /// can do any backwards failing. Implies AwaitingRemoteRevoke.
156         /// We have removed this HTLC in our latest commitment_signed and are now just waiting on a
157         /// revoke_and_ack to drop completely.
158         AwaitingRemovedRemoteRevoke(Option<HTLCFailReason>),
159 }
160
161 struct OutboundHTLCOutput {
162         htlc_id: u64,
163         amount_msat: u64,
164         cltv_expiry: u32,
165         payment_hash: PaymentHash,
166         state: OutboundHTLCState,
167         source: HTLCSource,
168 }
169
170 /// See AwaitingRemoteRevoke ChannelState for more info
171 enum HTLCUpdateAwaitingACK {
172         AddHTLC { // TODO: Time out if we're getting close to cltv_expiry
173                 // always outbound
174                 amount_msat: u64,
175                 cltv_expiry: u32,
176                 payment_hash: PaymentHash,
177                 source: HTLCSource,
178                 onion_routing_packet: msgs::OnionPacket,
179         },
180         ClaimHTLC {
181                 payment_preimage: PaymentPreimage,
182                 htlc_id: u64,
183         },
184         FailHTLC {
185                 htlc_id: u64,
186                 err_packet: msgs::OnionErrorPacket,
187         },
188 }
189
190 /// There are a few "states" and then a number of flags which can be applied:
191 /// We first move through init with OurInitSent -> TheirInitSent -> FundingCreated -> FundingSent.
192 /// TheirFundingLocked and OurFundingLocked then get set on FundingSent, and when both are set we
193 /// move on to ChannelFunded.
194 /// Note that PeerDisconnected can be set on both ChannelFunded and FundingSent.
195 /// ChannelFunded can then get all remaining flags set on it, until we finish shutdown, then we
196 /// move on to ShutdownComplete, at which point most calls into this channel are disallowed.
197 enum ChannelState {
198         /// Implies we have (or are prepared to) send our open_channel/accept_channel message
199         OurInitSent = 1 << 0,
200         /// Implies we have received their open_channel/accept_channel message
201         TheirInitSent = 1 << 1,
202         /// We have sent funding_created and are awaiting a funding_signed to advance to FundingSent.
203         /// Note that this is nonsense for an inbound channel as we immediately generate funding_signed
204         /// upon receipt of funding_created, so simply skip this state.
205         FundingCreated = 4,
206         /// Set when we have received/sent funding_created and funding_signed and are thus now waiting
207         /// on the funding transaction to confirm. The FundingLocked flags are set to indicate when we
208         /// and our counterparty consider the funding transaction confirmed.
209         FundingSent = 8,
210         /// Flag which can be set on FundingSent to indicate they sent us a funding_locked message.
211         /// Once both TheirFundingLocked and OurFundingLocked are set, state moves on to ChannelFunded.
212         TheirFundingLocked = 1 << 4,
213         /// Flag which can be set on FundingSent to indicate we sent them a funding_locked message.
214         /// Once both TheirFundingLocked and OurFundingLocked are set, state moves on to ChannelFunded.
215         OurFundingLocked = 1 << 5,
216         ChannelFunded = 64,
217         /// Flag which is set on ChannelFunded and FundingSent indicating remote side is considered
218         /// "disconnected" and no updates are allowed until after we've done a channel_reestablish
219         /// dance.
220         PeerDisconnected = 1 << 7,
221         /// Flag which is set on ChannelFunded, FundingCreated, and FundingSent indicating the user has
222         /// told us they failed to update our ChannelMonitor somewhere and we should pause sending any
223         /// outbound messages until they've managed to do so.
224         MonitorUpdateFailed = 1 << 8,
225         /// Flag which implies that we have sent a commitment_signed but are awaiting the responding
226         /// revoke_and_ack message. During this time period, we can't generate new commitment_signed
227         /// messages as then we will be unable to determine which HTLCs they included in their
228         /// revoke_and_ack implicit ACK, so instead we have to hold them away temporarily to be sent
229         /// later.
230         /// Flag is set on ChannelFunded.
231         AwaitingRemoteRevoke = 1 << 9,
232         /// Flag which is set on ChannelFunded or FundingSent after receiving a shutdown message from
233         /// the remote end. If set, they may not add any new HTLCs to the channel, and we are expected
234         /// to respond with our own shutdown message when possible.
235         RemoteShutdownSent = 1 << 10,
236         /// Flag which is set on ChannelFunded or FundingSent after sending a shutdown message. At this
237         /// point, we may not add any new HTLCs to the channel.
238         /// TODO: Investigate some kind of timeout mechanism by which point the remote end must provide
239         /// us their shutdown.
240         LocalShutdownSent = 1 << 11,
241         /// We've successfully negotiated a closing_signed dance. At this point ChannelManager is about
242         /// to drop us, but we store this anyway.
243         ShutdownComplete = 4096,
244 }
245 const BOTH_SIDES_SHUTDOWN_MASK: u32 = ChannelState::LocalShutdownSent as u32 | ChannelState::RemoteShutdownSent as u32;
246 const MULTI_STATE_FLAGS: u32 = BOTH_SIDES_SHUTDOWN_MASK | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32;
247
248 pub const INITIAL_COMMITMENT_NUMBER: u64 = (1 << 48) - 1;
249
250 /// The "channel disabled" bit in channel_update must be set based on whether we are connected to
251 /// our counterparty or not. However, we don't want to announce updates right away to avoid
252 /// spamming the network with updates if the connection is flapping. Instead, we "stage" updates to
253 /// our channel_update message and track the current state here.
254 /// See implementation at [`super::channelmanager::ChannelManager::timer_tick_occurred`].
255 #[derive(Clone, Copy, PartialEq)]
256 pub(super) enum ChannelUpdateStatus {
257         /// We've announced the channel as enabled and are connected to our peer.
258         Enabled,
259         /// Our channel is no longer live, but we haven't announced the channel as disabled yet.
260         DisabledStaged,
261         /// Our channel is live again, but we haven't announced the channel as enabled yet.
262         EnabledStaged,
263         /// We've announced the channel as disabled.
264         Disabled,
265 }
266
267 /// An enum indicating whether the local or remote side offered a given HTLC.
268 enum HTLCInitiator {
269         LocalOffered,
270         RemoteOffered,
271 }
272
273 /// Used when calculating whether we or the remote can afford an additional HTLC.
274 struct HTLCCandidate {
275         amount_msat: u64,
276         origin: HTLCInitiator,
277 }
278
279 impl HTLCCandidate {
280         fn new(amount_msat: u64, origin: HTLCInitiator) -> Self {
281                 Self {
282                         amount_msat,
283                         origin,
284                 }
285         }
286 }
287
288 /// Information needed for constructing an invoice route hint for this channel.
289 #[derive(Clone)]
290 pub struct CounterpartyForwardingInfo {
291         /// Base routing fee in millisatoshis.
292         pub fee_base_msat: u32,
293         /// Amount in millionths of a satoshi the channel will charge per transferred satoshi.
294         pub fee_proportional_millionths: u32,
295         /// The minimum difference in cltv_expiry between an ingoing HTLC and its outgoing counterpart,
296         /// such that the outgoing HTLC is forwardable to this counterparty. See `msgs::ChannelUpdate`'s
297         /// `cltv_expiry_delta` for more details.
298         pub cltv_expiry_delta: u16,
299 }
300
301 // TODO: We should refactor this to be an Inbound/OutboundChannel until initial setup handshaking
302 // has been completed, and then turn into a Channel to get compiler-time enforcement of things like
303 // calling channel_id() before we're set up or things like get_outbound_funding_signed on an
304 // inbound channel.
305 //
306 // Holder designates channel data owned for the benefice of the user client.
307 // Counterparty designates channel data owned by the another channel participant entity.
308 pub(super) struct Channel<Signer: Sign> {
309         config: ChannelConfig,
310
311         user_id: u64,
312
313         channel_id: [u8; 32],
314         channel_state: u32,
315         secp_ctx: Secp256k1<secp256k1::All>,
316         channel_value_satoshis: u64,
317
318         latest_monitor_update_id: u64,
319
320         holder_signer: Signer,
321         shutdown_pubkey: PublicKey,
322         destination_script: Script,
323
324         // Our commitment numbers start at 2^48-1 and count down, whereas the ones used in transaction
325         // generation start at 0 and count up...this simplifies some parts of implementation at the
326         // cost of others, but should really just be changed.
327
328         cur_holder_commitment_transaction_number: u64,
329         cur_counterparty_commitment_transaction_number: u64,
330         value_to_self_msat: u64, // Excluding all pending_htlcs, excluding fees
331         pending_inbound_htlcs: Vec<InboundHTLCOutput>,
332         pending_outbound_htlcs: Vec<OutboundHTLCOutput>,
333         holding_cell_htlc_updates: Vec<HTLCUpdateAwaitingACK>,
334
335         /// When resending CS/RAA messages on channel monitor restoration or on reconnect, we always
336         /// need to ensure we resend them in the order we originally generated them. Note that because
337         /// there can only ever be one in-flight CS and/or one in-flight RAA at any time, it is
338         /// sufficient to simply set this to the opposite of any message we are generating as we
339         /// generate it. ie when we generate a CS, we set this to RAAFirst as, if there is a pending
340         /// in-flight RAA to resend, it will have been the first thing we generated, and thus we should
341         /// send it first.
342         resend_order: RAACommitmentOrder,
343
344         monitor_pending_funding_locked: bool,
345         monitor_pending_revoke_and_ack: bool,
346         monitor_pending_commitment_signed: bool,
347         monitor_pending_forwards: Vec<(PendingHTLCInfo, u64)>,
348         monitor_pending_failures: Vec<(HTLCSource, PaymentHash, HTLCFailReason)>,
349
350         // pending_update_fee is filled when sending and receiving update_fee
351         // For outbound channel, feerate_per_kw is updated with the value from
352         // pending_update_fee when revoke_and_ack is received
353         //
354         // For inbound channel, feerate_per_kw is updated when it receives
355         // commitment_signed and revoke_and_ack is generated
356         // The pending value is kept when another pair of update_fee and commitment_signed
357         // is received during AwaitingRemoteRevoke and relieved when the expected
358         // revoke_and_ack is received and new commitment_signed is generated to be
359         // sent to the funder. Otherwise, the pending value is removed when receiving
360         // commitment_signed.
361         pending_update_fee: Option<u32>,
362         // update_fee() during ChannelState::AwaitingRemoteRevoke is hold in
363         // holdina_cell_update_fee then moved to pending_udpate_fee when revoke_and_ack
364         // is received. holding_cell_update_fee is updated when there are additional
365         // update_fee() during ChannelState::AwaitingRemoteRevoke.
366         holding_cell_update_fee: Option<u32>,
367         next_holder_htlc_id: u64,
368         next_counterparty_htlc_id: u64,
369         update_time_counter: u32,
370         feerate_per_kw: u32,
371
372         #[cfg(debug_assertions)]
373         /// Max to_local and to_remote outputs in a locally-generated commitment transaction
374         holder_max_commitment_tx_output: ::std::sync::Mutex<(u64, u64)>,
375         #[cfg(debug_assertions)]
376         /// Max to_local and to_remote outputs in a remote-generated commitment transaction
377         counterparty_max_commitment_tx_output: ::std::sync::Mutex<(u64, u64)>,
378
379         last_sent_closing_fee: Option<(u32, u64, Signature)>, // (feerate, fee, holder_sig)
380
381         /// The hash of the block in which the funding transaction was included.
382         funding_tx_confirmed_in: Option<BlockHash>,
383         funding_tx_confirmation_height: u32,
384         short_channel_id: Option<u64>,
385
386         counterparty_dust_limit_satoshis: u64,
387         #[cfg(test)]
388         pub(super) holder_dust_limit_satoshis: u64,
389         #[cfg(not(test))]
390         holder_dust_limit_satoshis: u64,
391         #[cfg(test)]
392         pub(super) counterparty_max_htlc_value_in_flight_msat: u64,
393         #[cfg(not(test))]
394         counterparty_max_htlc_value_in_flight_msat: u64,
395         //get_holder_max_htlc_value_in_flight_msat(): u64,
396         /// minimum channel reserve for self to maintain - set by them.
397         counterparty_selected_channel_reserve_satoshis: u64,
398         // get_holder_selected_channel_reserve_satoshis(channel_value_sats: u64): u64
399         counterparty_htlc_minimum_msat: u64,
400         holder_htlc_minimum_msat: u64,
401         #[cfg(test)]
402         pub counterparty_max_accepted_htlcs: u16,
403         #[cfg(not(test))]
404         counterparty_max_accepted_htlcs: u16,
405         //implied by OUR_MAX_HTLCS: max_accepted_htlcs: u16,
406         minimum_depth: u32,
407
408         counterparty_forwarding_info: Option<CounterpartyForwardingInfo>,
409
410         pub(crate) channel_transaction_parameters: ChannelTransactionParameters,
411         funding_transaction: Option<Transaction>,
412
413         counterparty_cur_commitment_point: Option<PublicKey>,
414         counterparty_prev_commitment_point: Option<PublicKey>,
415         counterparty_node_id: PublicKey,
416
417         counterparty_shutdown_scriptpubkey: Option<Script>,
418
419         commitment_secrets: CounterpartyCommitmentSecrets,
420
421         channel_update_status: ChannelUpdateStatus,
422
423         // We save these values so we can make sure `next_local_commit_tx_fee_msat` and
424         // `next_remote_commit_tx_fee_msat` properly predict what the next commitment transaction fee will
425         // be, by comparing the cached values to the fee of the tranaction generated by
426         // `build_commitment_transaction`.
427         #[cfg(any(test, feature = "fuzztarget"))]
428         next_local_commitment_tx_fee_info_cached: Mutex<Option<CommitmentTxInfoCached>>,
429         #[cfg(any(test, feature = "fuzztarget"))]
430         next_remote_commitment_tx_fee_info_cached: Mutex<Option<CommitmentTxInfoCached>>,
431 }
432
433 #[cfg(any(test, feature = "fuzztarget"))]
434 struct CommitmentTxInfoCached {
435         fee: u64,
436         total_pending_htlcs: usize,
437         next_holder_htlc_id: u64,
438         next_counterparty_htlc_id: u64,
439         feerate: u32,
440 }
441
442 pub const OUR_MAX_HTLCS: u16 = 50; //TODO
443 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
444
445 #[cfg(not(test))]
446 const COMMITMENT_TX_BASE_WEIGHT: u64 = 724;
447 #[cfg(test)]
448 pub const COMMITMENT_TX_BASE_WEIGHT: u64 = 724;
449 #[cfg(not(test))]
450 const COMMITMENT_TX_WEIGHT_PER_HTLC: u64 = 172;
451 #[cfg(test)]
452 pub const COMMITMENT_TX_WEIGHT_PER_HTLC: u64 = 172;
453
454 /// Maximmum `funding_satoshis` value, according to the BOLT #2 specification
455 /// it's 2^24.
456 pub const MAX_FUNDING_SATOSHIS: u64 = 1 << 24;
457
458 /// Maximum counterparty `dust_limit_satoshis` allowed. 2 * standard dust threshold on p2wsh output
459 /// Scales up on Bitcoin Core's proceeding policy with dust outputs. A typical p2wsh output is 43
460 /// bytes to which Core's `GetDustThreshold()` sums up a minimal spend of 67 bytes (even if
461 /// a p2wsh witnessScript might be *effectively* smaller), `dustRelayFee` is set to 3000sat/kb, thus
462 /// 110 * 3000 / 1000 = 330. Per-protocol rules, all time-sensitive outputs are p2wsh, a value of
463 /// 330 sats is the lower bound desired to ensure good propagation of transactions. We give a bit
464 /// of margin to our counterparty and pick up 660 satoshis as an accepted `dust_limit_satoshis`
465 /// upper bound to avoid negotiation conflicts with other implementations.
466 pub const MAX_DUST_LIMIT_SATOSHIS: u64 = 2 * 330;
467
468 /// A typical p2wsh output is 43 bytes to which Core's `GetDustThreshold()` sums up a minimal
469 /// spend of 67 bytes (even if a p2wsh witnessScript might be *effectively* smaller), `dustRelayFee`
470 /// is set to 3000sat/kb, thus 110 * 3000 / 1000 = 330. Per-protocol rules, all time-sensitive outputs
471 /// are p2wsh, a value of 330 sats is the lower bound desired to ensure good propagation of transactions.
472 pub const MIN_DUST_LIMIT_SATOSHIS: u64 = 330;
473
474 /// Used to return a simple Error back to ChannelManager. Will get converted to a
475 /// msgs::ErrorAction::SendErrorMessage or msgs::ErrorAction::IgnoreError as appropriate with our
476 /// channel_id in ChannelManager.
477 pub(super) enum ChannelError {
478         Ignore(String),
479         Close(String),
480         CloseDelayBroadcast(String),
481 }
482
483 impl fmt::Debug for ChannelError {
484         fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
485                 match self {
486                         &ChannelError::Ignore(ref e) => write!(f, "Ignore : {}", e),
487                         &ChannelError::Close(ref e) => write!(f, "Close : {}", e),
488                         &ChannelError::CloseDelayBroadcast(ref e) => write!(f, "CloseDelayBroadcast : {}", e)
489                 }
490         }
491 }
492
493 macro_rules! secp_check {
494         ($res: expr, $err: expr) => {
495                 match $res {
496                         Ok(thing) => thing,
497                         Err(_) => return Err(ChannelError::Close($err)),
498                 }
499         };
500 }
501
502 impl<Signer: Sign> Channel<Signer> {
503         // Convert constants + channel value to limits:
504         fn get_holder_max_htlc_value_in_flight_msat(channel_value_satoshis: u64) -> u64 {
505                 channel_value_satoshis * 1000 / 10 //TODO
506         }
507
508         /// Returns a minimum channel reserve value the remote needs to maintain,
509         /// required by us.
510         ///
511         /// Guaranteed to return a value no larger than channel_value_satoshis
512         pub(crate) fn get_holder_selected_channel_reserve_satoshis(channel_value_satoshis: u64) -> u64 {
513                 let (q, _) = channel_value_satoshis.overflowing_div(100);
514                 cmp::min(channel_value_satoshis, cmp::max(q, 1000)) //TODO
515         }
516
517         // Constructors:
518         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>
519         where K::Target: KeysInterface<Signer = Signer>,
520               F::Target: FeeEstimator,
521         {
522                 let holder_selected_contest_delay = config.own_channel_config.our_to_self_delay;
523                 let holder_signer = keys_provider.get_channel_signer(false, channel_value_satoshis);
524                 let pubkeys = holder_signer.pubkeys().clone();
525
526                 if channel_value_satoshis >= MAX_FUNDING_SATOSHIS {
527                         return Err(APIError::APIMisuseError{err: format!("funding_value must be smaller than {}, it was {}", MAX_FUNDING_SATOSHIS, channel_value_satoshis)});
528                 }
529                 let channel_value_msat = channel_value_satoshis * 1000;
530                 if push_msat > channel_value_msat {
531                         return Err(APIError::APIMisuseError { err: format!("Push value ({}) was larger than channel_value ({})", push_msat, channel_value_msat) });
532                 }
533                 if holder_selected_contest_delay < BREAKDOWN_TIMEOUT {
534                         return Err(APIError::APIMisuseError {err: format!("Configured with an unreasonable our_to_self_delay ({}) putting user funds at risks", holder_selected_contest_delay)});
535                 }
536                 let holder_selected_channel_reserve_satoshis = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(channel_value_satoshis);
537                 if holder_selected_channel_reserve_satoshis < MIN_DUST_LIMIT_SATOSHIS {
538                         return Err(APIError::APIMisuseError { err: format!("Holder selected channel  reserve below implemention limit dust_limit_satoshis {}", holder_selected_channel_reserve_satoshis) });
539                 }
540
541                 let feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
542
543                 let mut secp_ctx = Secp256k1::new();
544                 secp_ctx.seeded_randomize(&keys_provider.get_secure_random_bytes());
545
546                 Ok(Channel {
547                         user_id,
548                         config: config.channel_options.clone(),
549
550                         channel_id: keys_provider.get_secure_random_bytes(),
551                         channel_state: ChannelState::OurInitSent as u32,
552                         secp_ctx,
553                         channel_value_satoshis,
554
555                         latest_monitor_update_id: 0,
556
557                         holder_signer,
558                         shutdown_pubkey: keys_provider.get_shutdown_pubkey(),
559                         destination_script: keys_provider.get_destination_script(),
560
561                         cur_holder_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
562                         cur_counterparty_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
563                         value_to_self_msat: channel_value_satoshis * 1000 - push_msat,
564
565                         pending_inbound_htlcs: Vec::new(),
566                         pending_outbound_htlcs: Vec::new(),
567                         holding_cell_htlc_updates: Vec::new(),
568                         pending_update_fee: None,
569                         holding_cell_update_fee: None,
570                         next_holder_htlc_id: 0,
571                         next_counterparty_htlc_id: 0,
572                         update_time_counter: 1,
573
574                         resend_order: RAACommitmentOrder::CommitmentFirst,
575
576                         monitor_pending_funding_locked: false,
577                         monitor_pending_revoke_and_ack: false,
578                         monitor_pending_commitment_signed: false,
579                         monitor_pending_forwards: Vec::new(),
580                         monitor_pending_failures: Vec::new(),
581
582                         #[cfg(debug_assertions)]
583                         holder_max_commitment_tx_output: ::std::sync::Mutex::new((channel_value_satoshis * 1000 - push_msat, push_msat)),
584                         #[cfg(debug_assertions)]
585                         counterparty_max_commitment_tx_output: ::std::sync::Mutex::new((channel_value_satoshis * 1000 - push_msat, push_msat)),
586
587                         last_sent_closing_fee: None,
588
589                         funding_tx_confirmed_in: None,
590                         funding_tx_confirmation_height: 0,
591                         short_channel_id: None,
592
593                         feerate_per_kw: feerate,
594                         counterparty_dust_limit_satoshis: 0,
595                         holder_dust_limit_satoshis: MIN_DUST_LIMIT_SATOSHIS,
596                         counterparty_max_htlc_value_in_flight_msat: 0,
597                         counterparty_selected_channel_reserve_satoshis: 0,
598                         counterparty_htlc_minimum_msat: 0,
599                         holder_htlc_minimum_msat: if config.own_channel_config.our_htlc_minimum_msat == 0 { 1 } else { config.own_channel_config.our_htlc_minimum_msat },
600                         counterparty_max_accepted_htlcs: 0,
601                         minimum_depth: 0, // Filled in in accept_channel
602
603                         counterparty_forwarding_info: None,
604
605                         channel_transaction_parameters: ChannelTransactionParameters {
606                                 holder_pubkeys: pubkeys,
607                                 holder_selected_contest_delay: config.own_channel_config.our_to_self_delay,
608                                 is_outbound_from_holder: true,
609                                 counterparty_parameters: None,
610                                 funding_outpoint: None
611                         },
612                         funding_transaction: None,
613
614                         counterparty_cur_commitment_point: None,
615                         counterparty_prev_commitment_point: None,
616                         counterparty_node_id,
617
618                         counterparty_shutdown_scriptpubkey: None,
619
620                         commitment_secrets: CounterpartyCommitmentSecrets::new(),
621
622                         channel_update_status: ChannelUpdateStatus::Enabled,
623
624                         #[cfg(any(test, feature = "fuzztarget"))]
625                         next_local_commitment_tx_fee_info_cached: Mutex::new(None),
626                         #[cfg(any(test, feature = "fuzztarget"))]
627                         next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
628                 })
629         }
630
631         fn check_remote_fee<F: Deref>(fee_estimator: &F, feerate_per_kw: u32) -> Result<(), ChannelError>
632                 where F::Target: FeeEstimator
633         {
634                 let lower_limit = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
635                 if feerate_per_kw < lower_limit {
636                         return Err(ChannelError::Close(format!("Peer's feerate much too low. Actual: {}. Our expected lower limit: {}", feerate_per_kw, lower_limit)));
637                 }
638                 let upper_limit = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::HighPriority) as u64  * 2;
639                 if feerate_per_kw as u64 > upper_limit {
640                         return Err(ChannelError::Close(format!("Peer's feerate much too high. Actual: {}. Our expected upper limit: {}", feerate_per_kw, upper_limit)));
641                 }
642                 Ok(())
643         }
644
645         /// Creates a new channel from a remote sides' request for one.
646         /// Assumes chain_hash has already been checked and corresponds with what we expect!
647         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>
648                 where K::Target: KeysInterface<Signer = Signer>,
649           F::Target: FeeEstimator
650         {
651                 let holder_signer = keys_provider.get_channel_signer(true, msg.funding_satoshis);
652                 let pubkeys = holder_signer.pubkeys().clone();
653                 let counterparty_pubkeys = ChannelPublicKeys {
654                         funding_pubkey: msg.funding_pubkey,
655                         revocation_basepoint: msg.revocation_basepoint,
656                         payment_point: msg.payment_point,
657                         delayed_payment_basepoint: msg.delayed_payment_basepoint,
658                         htlc_basepoint: msg.htlc_basepoint
659                 };
660                 let mut local_config = (*config).channel_options.clone();
661
662                 if config.own_channel_config.our_to_self_delay < BREAKDOWN_TIMEOUT {
663                         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)));
664                 }
665
666                 // Check sanity of message fields:
667                 if msg.funding_satoshis >= MAX_FUNDING_SATOSHIS {
668                         return Err(ChannelError::Close(format!("Funding must be smaller than {}. It was {}", MAX_FUNDING_SATOSHIS, msg.funding_satoshis)));
669                 }
670                 if msg.channel_reserve_satoshis > msg.funding_satoshis {
671                         return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must be not greater than funding_satoshis: {}", msg.channel_reserve_satoshis, msg.funding_satoshis)));
672                 }
673                 let funding_value = (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000;
674                 if msg.push_msat > funding_value {
675                         return Err(ChannelError::Close(format!("push_msat {} was larger than funding value {}", msg.push_msat, funding_value)));
676                 }
677                 if msg.dust_limit_satoshis > msg.funding_satoshis {
678                         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)));
679                 }
680                 if msg.dust_limit_satoshis > msg.channel_reserve_satoshis {
681                         return Err(ChannelError::Close(format!("Bogus; channel reserve ({}) is less than dust limit ({})", msg.channel_reserve_satoshis, msg.dust_limit_satoshis)));
682                 }
683                 let full_channel_value_msat = (msg.funding_satoshis - msg.channel_reserve_satoshis) * 1000;
684                 if msg.htlc_minimum_msat >= full_channel_value_msat {
685                         return Err(ChannelError::Close(format!("Minimum htlc value ({}) was larger than full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat)));
686                 }
687                 Channel::<Signer>::check_remote_fee(fee_estimator, msg.feerate_per_kw)?;
688
689                 let max_counterparty_selected_contest_delay = u16::min(config.peer_channel_config_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
690                 if msg.to_self_delay > max_counterparty_selected_contest_delay {
691                         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)));
692                 }
693                 if msg.max_accepted_htlcs < 1 {
694                         return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel".to_owned()));
695                 }
696                 if msg.max_accepted_htlcs > MAX_HTLCS {
697                         return Err(ChannelError::Close(format!("max_accepted_htlcs was {}. It must not be larger than {}", msg.max_accepted_htlcs, MAX_HTLCS)));
698                 }
699
700                 // Now check against optional parameters as set by config...
701                 if msg.funding_satoshis < config.peer_channel_config_limits.min_funding_satoshis {
702                         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)));
703                 }
704                 if msg.htlc_minimum_msat > config.peer_channel_config_limits.max_htlc_minimum_msat {
705                         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)));
706                 }
707                 if msg.max_htlc_value_in_flight_msat < config.peer_channel_config_limits.min_max_htlc_value_in_flight_msat {
708                         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)));
709                 }
710                 if msg.channel_reserve_satoshis > config.peer_channel_config_limits.max_channel_reserve_satoshis {
711                         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)));
712                 }
713                 if msg.max_accepted_htlcs < config.peer_channel_config_limits.min_max_accepted_htlcs {
714                         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)));
715                 }
716                 if msg.dust_limit_satoshis < MIN_DUST_LIMIT_SATOSHIS {
717                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the implementation limit ({})", msg.dust_limit_satoshis, MIN_DUST_LIMIT_SATOSHIS)));
718                 }
719                 if msg.dust_limit_satoshis >  MAX_DUST_LIMIT_SATOSHIS {
720                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the implementation limit ({})", msg.dust_limit_satoshis, MAX_DUST_LIMIT_SATOSHIS)));
721                 }
722
723                 // Convert things into internal flags and prep our state:
724
725                 let announce = if (msg.channel_flags & 1) == 1 { true } else { false };
726                 if config.peer_channel_config_limits.force_announced_channel_preference {
727                         if local_config.announced_channel != announce {
728                                 return Err(ChannelError::Close("Peer tried to open channel but their announcement preference is different from ours".to_owned()));
729                         }
730                 }
731                 // we either accept their preference or the preferences match
732                 local_config.announced_channel = announce;
733
734                 let background_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
735
736                 let holder_selected_channel_reserve_satoshis = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(msg.funding_satoshis);
737                 if holder_selected_channel_reserve_satoshis < MIN_DUST_LIMIT_SATOSHIS {
738                         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)));
739                 }
740                 if msg.channel_reserve_satoshis < MIN_DUST_LIMIT_SATOSHIS {
741                         return Err(ChannelError::Close(format!("channel_reserve_satoshis ({}) is smaller than our dust limit ({})", msg.channel_reserve_satoshis, MIN_DUST_LIMIT_SATOSHIS)));
742                 }
743                 if holder_selected_channel_reserve_satoshis < msg.dust_limit_satoshis {
744                         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)));
745                 }
746
747                 // check if the funder's amount for the initial commitment tx is sufficient
748                 // for full fee payment
749                 let funders_amount_msat = msg.funding_satoshis * 1000 - msg.push_msat;
750                 let lower_limit = background_feerate as u64 * COMMITMENT_TX_BASE_WEIGHT;
751                 if funders_amount_msat < lower_limit {
752                         return Err(ChannelError::Close(format!("Insufficient funding amount ({}) for initial commitment. Must be at least {}", funders_amount_msat, lower_limit)));
753                 }
754
755                 let to_local_msat = msg.push_msat;
756                 let to_remote_msat = funders_amount_msat - background_feerate as u64 * COMMITMENT_TX_BASE_WEIGHT;
757                 if to_local_msat <= msg.channel_reserve_satoshis * 1000 && to_remote_msat <= holder_selected_channel_reserve_satoshis * 1000 {
758                         return Err(ChannelError::Close("Insufficient funding amount for initial commitment".to_owned()));
759                 }
760
761                 let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() {
762                         match &msg.shutdown_scriptpubkey {
763                                 &OptionalField::Present(ref script) => {
764                                         // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything
765                                         if script.len() == 0 {
766                                                 None
767                                         // Peer is signaling upfront_shutdown and has provided a non-accepted scriptpubkey format. Fail the channel
768                                         } else if is_unsupported_shutdown_script(&their_features, script) {
769                                                 return Err(ChannelError::Close(format!("Peer is signaling upfront_shutdown but has provided a non-accepted scriptpubkey format. script: ({})", script.to_bytes().to_hex())));
770                                         } else {
771                                                 Some(script.clone())
772                                         }
773                                 },
774                                 // 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
775                                 &OptionalField::Absent => {
776                                         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()));
777                                 }
778                         }
779                 } else { None };
780
781                 let mut secp_ctx = Secp256k1::new();
782                 secp_ctx.seeded_randomize(&keys_provider.get_secure_random_bytes());
783
784                 let chan = Channel {
785                         user_id,
786                         config: local_config,
787
788                         channel_id: msg.temporary_channel_id,
789                         channel_state: (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32),
790                         secp_ctx,
791
792                         latest_monitor_update_id: 0,
793
794                         holder_signer,
795                         shutdown_pubkey: keys_provider.get_shutdown_pubkey(),
796                         destination_script: keys_provider.get_destination_script(),
797
798                         cur_holder_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
799                         cur_counterparty_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
800                         value_to_self_msat: msg.push_msat,
801
802                         pending_inbound_htlcs: Vec::new(),
803                         pending_outbound_htlcs: Vec::new(),
804                         holding_cell_htlc_updates: Vec::new(),
805                         pending_update_fee: None,
806                         holding_cell_update_fee: None,
807                         next_holder_htlc_id: 0,
808                         next_counterparty_htlc_id: 0,
809                         update_time_counter: 1,
810
811                         resend_order: RAACommitmentOrder::CommitmentFirst,
812
813                         monitor_pending_funding_locked: false,
814                         monitor_pending_revoke_and_ack: false,
815                         monitor_pending_commitment_signed: false,
816                         monitor_pending_forwards: Vec::new(),
817                         monitor_pending_failures: Vec::new(),
818
819                         #[cfg(debug_assertions)]
820                         holder_max_commitment_tx_output: ::std::sync::Mutex::new((msg.push_msat, msg.funding_satoshis * 1000 - msg.push_msat)),
821                         #[cfg(debug_assertions)]
822                         counterparty_max_commitment_tx_output: ::std::sync::Mutex::new((msg.push_msat, msg.funding_satoshis * 1000 - msg.push_msat)),
823
824                         last_sent_closing_fee: None,
825
826                         funding_tx_confirmed_in: None,
827                         funding_tx_confirmation_height: 0,
828                         short_channel_id: None,
829
830                         feerate_per_kw: msg.feerate_per_kw,
831                         channel_value_satoshis: msg.funding_satoshis,
832                         counterparty_dust_limit_satoshis: msg.dust_limit_satoshis,
833                         holder_dust_limit_satoshis: MIN_DUST_LIMIT_SATOSHIS,
834                         counterparty_max_htlc_value_in_flight_msat: cmp::min(msg.max_htlc_value_in_flight_msat, msg.funding_satoshis * 1000),
835                         counterparty_selected_channel_reserve_satoshis: msg.channel_reserve_satoshis,
836                         counterparty_htlc_minimum_msat: msg.htlc_minimum_msat,
837                         holder_htlc_minimum_msat: if config.own_channel_config.our_htlc_minimum_msat == 0 { 1 } else { config.own_channel_config.our_htlc_minimum_msat },
838                         counterparty_max_accepted_htlcs: msg.max_accepted_htlcs,
839                         minimum_depth: config.own_channel_config.minimum_depth,
840
841                         counterparty_forwarding_info: None,
842
843                         channel_transaction_parameters: ChannelTransactionParameters {
844                                 holder_pubkeys: pubkeys,
845                                 holder_selected_contest_delay: config.own_channel_config.our_to_self_delay,
846                                 is_outbound_from_holder: false,
847                                 counterparty_parameters: Some(CounterpartyChannelTransactionParameters {
848                                         selected_contest_delay: msg.to_self_delay,
849                                         pubkeys: counterparty_pubkeys,
850                                 }),
851                                 funding_outpoint: None
852                         },
853                         funding_transaction: None,
854
855                         counterparty_cur_commitment_point: Some(msg.first_per_commitment_point),
856                         counterparty_prev_commitment_point: None,
857                         counterparty_node_id,
858
859                         counterparty_shutdown_scriptpubkey,
860
861                         commitment_secrets: CounterpartyCommitmentSecrets::new(),
862
863                         channel_update_status: ChannelUpdateStatus::Enabled,
864
865                         #[cfg(any(test, feature = "fuzztarget"))]
866                         next_local_commitment_tx_fee_info_cached: Mutex::new(None),
867                         #[cfg(any(test, feature = "fuzztarget"))]
868                         next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
869                 };
870
871                 Ok(chan)
872         }
873
874         /// Transaction nomenclature is somewhat confusing here as there are many different cases - a
875         /// transaction is referred to as "a's transaction" implying that a will be able to broadcast
876         /// the transaction. Thus, b will generally be sending a signature over such a transaction to
877         /// a, and a can revoke the transaction by providing b the relevant per_commitment_secret. As
878         /// such, a transaction is generally the result of b increasing the amount paid to a (or adding
879         /// an HTLC to a).
880         /// @local is used only to convert relevant internal structures which refer to remote vs local
881         /// to decide value of outputs and direction of HTLCs.
882         /// @generated_by_local is used to determine *which* HTLCs to include - noting that the HTLC
883         /// state may indicate that one peer has informed the other that they'd like to add an HTLC but
884         /// have not yet committed it. Such HTLCs will only be included in transactions which are being
885         /// generated by the peer which proposed adding the HTLCs, and thus we need to understand both
886         /// which peer generated this transaction and "to whom" this transaction flows.
887         /// Returns (the transaction info, the number of HTLC outputs which were present in the
888         /// transaction, the list of HTLCs which were not ignored when building the transaction).
889         /// Note that below-dust HTLCs are included in the third return value, but not the second, and
890         /// sources are provided only for outbound HTLCs in the third return value.
891         #[inline]
892         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 {
893                 let mut included_dust_htlcs: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::new();
894                 let num_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len();
895                 let mut included_non_dust_htlcs: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::with_capacity(num_htlcs);
896
897                 let broadcaster_dust_limit_satoshis = if local { self.holder_dust_limit_satoshis } else { self.counterparty_dust_limit_satoshis };
898                 let mut remote_htlc_total_msat = 0;
899                 let mut local_htlc_total_msat = 0;
900                 let mut value_to_self_msat_offset = 0;
901
902                 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);
903
904                 macro_rules! get_htlc_in_commitment {
905                         ($htlc: expr, $offered: expr) => {
906                                 HTLCOutputInCommitment {
907                                         offered: $offered,
908                                         amount_msat: $htlc.amount_msat,
909                                         cltv_expiry: $htlc.cltv_expiry,
910                                         payment_hash: $htlc.payment_hash,
911                                         transaction_output_index: None
912                                 }
913                         }
914                 }
915
916                 macro_rules! add_htlc_output {
917                         ($htlc: expr, $outbound: expr, $source: expr, $state_name: expr) => {
918                                 if $outbound == local { // "offered HTLC output"
919                                         let htlc_in_tx = get_htlc_in_commitment!($htlc, true);
920                                         if $htlc.amount_msat / 1000 >= broadcaster_dust_limit_satoshis + (feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) {
921                                                 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);
922                                                 included_non_dust_htlcs.push((htlc_in_tx, $source));
923                                         } else {
924                                                 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);
925                                                 included_dust_htlcs.push((htlc_in_tx, $source));
926                                         }
927                                 } else {
928                                         let htlc_in_tx = get_htlc_in_commitment!($htlc, false);
929                                         if $htlc.amount_msat / 1000 >= broadcaster_dust_limit_satoshis + (feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) {
930                                                 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);
931                                                 included_non_dust_htlcs.push((htlc_in_tx, $source));
932                                         } else {
933                                                 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);
934                                                 included_dust_htlcs.push((htlc_in_tx, $source));
935                                         }
936                                 }
937                         }
938                 }
939
940                 for ref htlc in self.pending_inbound_htlcs.iter() {
941                         let (include, state_name) = match htlc.state {
942                                 InboundHTLCState::RemoteAnnounced(_) => (!generated_by_local, "RemoteAnnounced"),
943                                 InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_) => (!generated_by_local, "AwaitingRemoteRevokeToAnnounce"),
944                                 InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) => (true, "AwaitingAnnouncedRemoteRevoke"),
945                                 InboundHTLCState::Committed => (true, "Committed"),
946                                 InboundHTLCState::LocalRemoved(_) => (!generated_by_local, "LocalRemoved"),
947                         };
948
949                         if include {
950                                 add_htlc_output!(htlc, false, None, state_name);
951                                 remote_htlc_total_msat += htlc.amount_msat;
952                         } else {
953                                 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);
954                                 match &htlc.state {
955                                         &InboundHTLCState::LocalRemoved(ref reason) => {
956                                                 if generated_by_local {
957                                                         if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
958                                                                 value_to_self_msat_offset += htlc.amount_msat as i64;
959                                                         }
960                                                 }
961                                         },
962                                         _ => {},
963                                 }
964                         }
965                 }
966
967                 for ref htlc in self.pending_outbound_htlcs.iter() {
968                         let (include, state_name) = match htlc.state {
969                                 OutboundHTLCState::LocalAnnounced(_) => (generated_by_local, "LocalAnnounced"),
970                                 OutboundHTLCState::Committed => (true, "Committed"),
971                                 OutboundHTLCState::RemoteRemoved(_) => (generated_by_local, "RemoteRemoved"),
972                                 OutboundHTLCState::AwaitingRemoteRevokeToRemove(_) => (generated_by_local, "AwaitingRemoteRevokeToRemove"),
973                                 OutboundHTLCState::AwaitingRemovedRemoteRevoke(_) => (false, "AwaitingRemovedRemoteRevoke"),
974                         };
975
976                         if include {
977                                 add_htlc_output!(htlc, true, Some(&htlc.source), state_name);
978                                 local_htlc_total_msat += htlc.amount_msat;
979                         } else {
980                                 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);
981                                 match htlc.state {
982                                         OutboundHTLCState::AwaitingRemoteRevokeToRemove(None)|OutboundHTLCState::AwaitingRemovedRemoteRevoke(None) => {
983                                                 value_to_self_msat_offset -= htlc.amount_msat as i64;
984                                         },
985                                         OutboundHTLCState::RemoteRemoved(None) => {
986                                                 if !generated_by_local {
987                                                         value_to_self_msat_offset -= htlc.amount_msat as i64;
988                                                 }
989                                         },
990                                         _ => {},
991                                 }
992                         }
993                 }
994
995                 let value_to_self_msat: i64 = (self.value_to_self_msat - local_htlc_total_msat) as i64 + value_to_self_msat_offset;
996                 assert!(value_to_self_msat >= 0);
997                 // Note that in case they have several just-awaiting-last-RAA fulfills in-progress (ie
998                 // AwaitingRemoteRevokeToRemove or AwaitingRemovedRemoteRevoke) we may have allowed them to
999                 // "violate" their reserve value by couting those against it. Thus, we have to convert
1000                 // everything to i64 before subtracting as otherwise we can overflow.
1001                 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;
1002                 assert!(value_to_remote_msat >= 0);
1003
1004                 #[cfg(debug_assertions)]
1005                 {
1006                         // Make sure that the to_self/to_remote is always either past the appropriate
1007                         // channel_reserve *or* it is making progress towards it.
1008                         let mut broadcaster_max_commitment_tx_output = if generated_by_local {
1009                                 self.holder_max_commitment_tx_output.lock().unwrap()
1010                         } else {
1011                                 self.counterparty_max_commitment_tx_output.lock().unwrap()
1012                         };
1013                         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);
1014                         broadcaster_max_commitment_tx_output.0 = cmp::max(broadcaster_max_commitment_tx_output.0, value_to_self_msat as u64);
1015                         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);
1016                         broadcaster_max_commitment_tx_output.1 = cmp::max(broadcaster_max_commitment_tx_output.1, value_to_remote_msat as u64);
1017                 }
1018
1019                 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;
1020                 let (value_to_self, value_to_remote) = if self.is_outbound() {
1021                         (value_to_self_msat / 1000 - total_fee as i64, value_to_remote_msat / 1000)
1022                 } else {
1023                         (value_to_self_msat / 1000, value_to_remote_msat / 1000 - total_fee as i64)
1024                 };
1025
1026                 let mut value_to_a = if local { value_to_self } else { value_to_remote };
1027                 let mut value_to_b = if local { value_to_remote } else { value_to_self };
1028
1029                 if value_to_a >= (broadcaster_dust_limit_satoshis as i64) {
1030                         log_trace!(logger, "   ...including {} output with value {}", if local { "to_local" } else { "to_remote" }, value_to_a);
1031                 } else {
1032                         value_to_a = 0;
1033                 }
1034
1035                 if value_to_b >= (broadcaster_dust_limit_satoshis as i64) {
1036                         log_trace!(logger, "   ...including {} output with value {}", if local { "to_remote" } else { "to_local" }, value_to_b);
1037                 } else {
1038                         value_to_b = 0;
1039                 }
1040
1041                 let num_nondust_htlcs = included_non_dust_htlcs.len();
1042
1043                 let channel_parameters =
1044                         if local { self.channel_transaction_parameters.as_holder_broadcastable() }
1045                         else { self.channel_transaction_parameters.as_counterparty_broadcastable() };
1046                 let tx = CommitmentTransaction::new_with_auxiliary_htlc_data(commitment_number,
1047                                                                              value_to_a as u64,
1048                                                                              value_to_b as u64,
1049                                                                              keys.clone(),
1050                                                                              feerate_per_kw,
1051                                                                              &mut included_non_dust_htlcs,
1052                                                                              &channel_parameters
1053                 );
1054                 let mut htlcs_included = included_non_dust_htlcs;
1055                 // The unwrap is safe, because all non-dust HTLCs have been assigned an output index
1056                 htlcs_included.sort_unstable_by_key(|h| h.0.transaction_output_index.unwrap());
1057                 htlcs_included.append(&mut included_dust_htlcs);
1058
1059                 (tx, num_nondust_htlcs, htlcs_included)
1060         }
1061
1062         #[inline]
1063         fn get_closing_scriptpubkey(&self) -> Script {
1064                 let channel_close_key_hash = WPubkeyHash::hash(&self.shutdown_pubkey.serialize());
1065                 Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&channel_close_key_hash[..]).into_script()
1066         }
1067
1068         #[inline]
1069         fn get_closing_transaction_weight(&self, a_scriptpubkey: Option<&Script>, b_scriptpubkey: Option<&Script>) -> u64 {
1070                 let mut ret =
1071                 (4 +                                           // version
1072                  1 +                                           // input count
1073                  36 +                                          // prevout
1074                  1 +                                           // script length (0)
1075                  4 +                                           // sequence
1076                  1 +                                           // output count
1077                  4                                             // lock time
1078                  )*4 +                                         // * 4 for non-witness parts
1079                 2 +                                            // witness marker and flag
1080                 1 +                                            // witness element count
1081                 4 +                                            // 4 element lengths (2 sigs, multisig dummy, and witness script)
1082                 self.get_funding_redeemscript().len() as u64 + // funding witness script
1083                 2*(1 + 71);                                    // two signatures + sighash type flags
1084                 if let Some(spk) = a_scriptpubkey {
1085                         ret += ((8+1) +                            // output values and script length
1086                                 spk.len() as u64) * 4;                 // scriptpubkey and witness multiplier
1087                 }
1088                 if let Some(spk) = b_scriptpubkey {
1089                         ret += ((8+1) +                            // output values and script length
1090                                 spk.len() as u64) * 4;                 // scriptpubkey and witness multiplier
1091                 }
1092                 ret
1093         }
1094
1095         #[inline]
1096         fn build_closing_transaction(&self, proposed_total_fee_satoshis: u64, skip_remote_output: bool) -> (Transaction, u64) {
1097                 let txins = {
1098                         let mut ins: Vec<TxIn> = Vec::new();
1099                         ins.push(TxIn {
1100                                 previous_output: self.funding_outpoint().into_bitcoin_outpoint(),
1101                                 script_sig: Script::new(),
1102                                 sequence: 0xffffffff,
1103                                 witness: Vec::new(),
1104                         });
1105                         ins
1106                 };
1107
1108                 assert!(self.pending_inbound_htlcs.is_empty());
1109                 assert!(self.pending_outbound_htlcs.is_empty());
1110                 let mut txouts: Vec<(TxOut, ())> = Vec::new();
1111
1112                 let mut total_fee_satoshis = proposed_total_fee_satoshis;
1113                 let value_to_self: i64 = (self.value_to_self_msat as i64) / 1000 - if self.is_outbound() { total_fee_satoshis as i64 } else { 0 };
1114                 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 };
1115
1116                 if value_to_self < 0 {
1117                         assert!(self.is_outbound());
1118                         total_fee_satoshis += (-value_to_self) as u64;
1119                 } else if value_to_remote < 0 {
1120                         assert!(!self.is_outbound());
1121                         total_fee_satoshis += (-value_to_remote) as u64;
1122                 }
1123
1124                 if !skip_remote_output && value_to_remote as u64 > self.holder_dust_limit_satoshis {
1125                         txouts.push((TxOut {
1126                                 script_pubkey: self.counterparty_shutdown_scriptpubkey.clone().unwrap(),
1127                                 value: value_to_remote as u64
1128                         }, ()));
1129                 }
1130
1131                 if value_to_self as u64 > self.holder_dust_limit_satoshis {
1132                         txouts.push((TxOut {
1133                                 script_pubkey: self.get_closing_scriptpubkey(),
1134                                 value: value_to_self as u64
1135                         }, ()));
1136                 }
1137
1138                 transaction_utils::sort_outputs(&mut txouts, |_, _| { cmp::Ordering::Equal }); // Ordering doesnt matter if they used our pubkey...
1139
1140                 let mut outputs: Vec<TxOut> = Vec::new();
1141                 for out in txouts.drain(..) {
1142                         outputs.push(out.0);
1143                 }
1144
1145                 (Transaction {
1146                         version: 2,
1147                         lock_time: 0,
1148                         input: txins,
1149                         output: outputs,
1150                 }, total_fee_satoshis)
1151         }
1152
1153         fn funding_outpoint(&self) -> OutPoint {
1154                 self.channel_transaction_parameters.funding_outpoint.unwrap()
1155         }
1156
1157         #[inline]
1158         /// Creates a set of keys for build_commitment_transaction to generate a transaction which our
1159         /// counterparty will sign (ie DO NOT send signatures over a transaction created by this to
1160         /// our counterparty!)
1161         /// The result is a transaction which we can revoke broadcastership of (ie a "local" transaction)
1162         /// TODO Some magic rust shit to compile-time check this?
1163         fn build_holder_transaction_keys(&self, commitment_number: u64) -> Result<TxCreationKeys, ChannelError> {
1164                 let per_commitment_point = self.holder_signer.get_per_commitment_point(commitment_number, &self.secp_ctx);
1165                 let delayed_payment_base = &self.get_holder_pubkeys().delayed_payment_basepoint;
1166                 let htlc_basepoint = &self.get_holder_pubkeys().htlc_basepoint;
1167                 let counterparty_pubkeys = self.get_counterparty_pubkeys();
1168
1169                 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()))
1170         }
1171
1172         #[inline]
1173         /// Creates a set of keys for build_commitment_transaction to generate a transaction which we
1174         /// will sign and send to our counterparty.
1175         /// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
1176         fn build_remote_transaction_keys(&self) -> Result<TxCreationKeys, ChannelError> {
1177                 //TODO: Ensure that the payment_key derived here ends up in the library users' wallet as we
1178                 //may see payments to it!
1179                 let revocation_basepoint = &self.get_holder_pubkeys().revocation_basepoint;
1180                 let htlc_basepoint = &self.get_holder_pubkeys().htlc_basepoint;
1181                 let counterparty_pubkeys = self.get_counterparty_pubkeys();
1182
1183                 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()))
1184         }
1185
1186         /// Gets the redeemscript for the funding transaction output (ie the funding transaction output
1187         /// pays to get_funding_redeemscript().to_v0_p2wsh()).
1188         /// Panics if called before accept_channel/new_from_req
1189         pub fn get_funding_redeemscript(&self) -> Script {
1190                 make_funding_redeemscript(&self.get_holder_pubkeys().funding_pubkey, self.counterparty_funding_pubkey())
1191         }
1192
1193         /// Builds the htlc-success or htlc-timeout transaction which spends a given HTLC output
1194         /// @local is used only to convert relevant internal structures which refer to remote vs local
1195         /// to decide value of outputs and direction of HTLCs.
1196         fn build_htlc_transaction(&self, prev_hash: &Txid, htlc: &HTLCOutputInCommitment, local: bool, keys: &TxCreationKeys, feerate_per_kw: u32) -> Transaction {
1197                 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)
1198         }
1199
1200         /// Per HTLC, only one get_update_fail_htlc or get_update_fulfill_htlc call may be made.
1201         /// In such cases we debug_assert!(false) and return a ChannelError::Ignore. Thus, will always
1202         /// return Ok(_) if debug assertions are turned on or preconditions are met.
1203         ///
1204         /// Note that it is still possible to hit these assertions in case we find a preimage on-chain
1205         /// but then have a reorg which settles on an HTLC-failure on chain.
1206         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 {
1207                 // Either ChannelFunded got set (which means it won't be unset) or there is no way any
1208                 // caller thought we could have something claimed (cause we wouldn't have accepted in an
1209                 // incoming HTLC anyway). If we got to ShutdownComplete, callers aren't allowed to call us,
1210                 // either.
1211                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1212                         panic!("Was asked to fulfill an HTLC when channel was not in an operational state");
1213                 }
1214                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
1215
1216                 let payment_hash_calc = PaymentHash(Sha256::hash(&payment_preimage_arg.0[..]).into_inner());
1217
1218                 // ChannelManager may generate duplicate claims/fails due to HTLC update events from
1219                 // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
1220                 // these, but for now we just have to treat them as normal.
1221
1222                 let mut pending_idx = core::usize::MAX;
1223                 for (idx, htlc) in self.pending_inbound_htlcs.iter().enumerate() {
1224                         if htlc.htlc_id == htlc_id_arg {
1225                                 assert_eq!(htlc.payment_hash, payment_hash_calc);
1226                                 match htlc.state {
1227                                         InboundHTLCState::Committed => {},
1228                                         InboundHTLCState::LocalRemoved(ref reason) => {
1229                                                 if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
1230                                                 } else {
1231                                                         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()));
1232                                                 }
1233                                                 debug_assert!(false, "Tried to fulfill an HTLC that was already fail/fulfilled");
1234                                                 return Ok((None, None));
1235                                         },
1236                                         _ => {
1237                                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1238                                                 // Don't return in release mode here so that we can update channel_monitor
1239                                         }
1240                                 }
1241                                 pending_idx = idx;
1242                                 break;
1243                         }
1244                 }
1245                 if pending_idx == core::usize::MAX {
1246                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
1247                 }
1248
1249                 // Now update local state:
1250                 //
1251                 // We have to put the payment_preimage in the channel_monitor right away here to ensure we
1252                 // can claim it even if the channel hits the chain before we see their next commitment.
1253                 self.latest_monitor_update_id += 1;
1254                 let monitor_update = ChannelMonitorUpdate {
1255                         update_id: self.latest_monitor_update_id,
1256                         updates: vec![ChannelMonitorUpdateStep::PaymentPreimage {
1257                                 payment_preimage: payment_preimage_arg.clone(),
1258                         }],
1259                 };
1260
1261                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
1262                         for pending_update in self.holding_cell_htlc_updates.iter() {
1263                                 match pending_update {
1264                                         &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
1265                                                 if htlc_id_arg == htlc_id {
1266                                                         // Make sure we don't leave latest_monitor_update_id incremented here:
1267                                                         self.latest_monitor_update_id -= 1;
1268                                                         debug_assert!(false, "Tried to fulfill an HTLC that was already fulfilled");
1269                                                         return Ok((None, None));
1270                                                 }
1271                                         },
1272                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
1273                                                 if htlc_id_arg == htlc_id {
1274                                                         log_warn!(logger, "Have preimage and want to fulfill HTLC with pending failure against channel {}", log_bytes!(self.channel_id()));
1275                                                         // TODO: We may actually be able to switch to a fulfill here, though its
1276                                                         // rare enough it may not be worth the complexity burden.
1277                                                         debug_assert!(false, "Tried to fulfill an HTLC that was already failed");
1278                                                         return Ok((None, Some(monitor_update)));
1279                                                 }
1280                                         },
1281                                         _ => {}
1282                                 }
1283                         }
1284                         log_trace!(logger, "Adding HTLC claim to holding_cell! Current state: {}", self.channel_state);
1285                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::ClaimHTLC {
1286                                 payment_preimage: payment_preimage_arg, htlc_id: htlc_id_arg,
1287                         });
1288                         return Ok((None, Some(monitor_update)));
1289                 }
1290
1291                 {
1292                         let htlc = &mut self.pending_inbound_htlcs[pending_idx];
1293                         if let InboundHTLCState::Committed = htlc.state {
1294                         } else {
1295                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1296                                 return Ok((None, Some(monitor_update)));
1297                         }
1298                         log_trace!(logger, "Upgrading HTLC {} to LocalRemoved with a Fulfill!", log_bytes!(htlc.payment_hash.0));
1299                         htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::Fulfill(payment_preimage_arg.clone()));
1300                 }
1301
1302                 Ok((Some(msgs::UpdateFulfillHTLC {
1303                         channel_id: self.channel_id(),
1304                         htlc_id: htlc_id_arg,
1305                         payment_preimage: payment_preimage_arg,
1306                 }), Some(monitor_update)))
1307         }
1308
1309         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 {
1310                 match self.get_update_fulfill_htlc(htlc_id, payment_preimage, logger)? {
1311                         (Some(update_fulfill_htlc), Some(mut monitor_update)) => {
1312                                 let (commitment, mut additional_update) = self.send_commitment_no_status_check(logger)?;
1313                                 // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
1314                                 // strictly increasing by one, so decrement it here.
1315                                 self.latest_monitor_update_id = monitor_update.update_id;
1316                                 monitor_update.updates.append(&mut additional_update.updates);
1317                                 Ok((Some((update_fulfill_htlc, commitment)), Some(monitor_update)))
1318                         },
1319                         (Some(update_fulfill_htlc), None) => {
1320                                 let (commitment, monitor_update) = self.send_commitment_no_status_check(logger)?;
1321                                 Ok((Some((update_fulfill_htlc, commitment)), Some(monitor_update)))
1322                         },
1323                         (None, Some(monitor_update)) => Ok((None, Some(monitor_update))),
1324                         (None, None) => Ok((None, None))
1325                 }
1326         }
1327
1328         /// Per HTLC, only one get_update_fail_htlc or get_update_fulfill_htlc call may be made.
1329         /// In such cases we debug_assert!(false) and return a ChannelError::Ignore. Thus, will always
1330         /// return Ok(_) if debug assertions are turned on or preconditions are met.
1331         ///
1332         /// Note that it is still possible to hit these assertions in case we find a preimage on-chain
1333         /// but then have a reorg which settles on an HTLC-failure on chain.
1334         pub fn get_update_fail_htlc(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket) -> Result<Option<msgs::UpdateFailHTLC>, ChannelError> {
1335                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
1336                         panic!("Was asked to fail an HTLC when channel was not in an operational state");
1337                 }
1338                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
1339
1340                 // ChannelManager may generate duplicate claims/fails due to HTLC update events from
1341                 // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
1342                 // these, but for now we just have to treat them as normal.
1343
1344                 let mut pending_idx = core::usize::MAX;
1345                 for (idx, htlc) in self.pending_inbound_htlcs.iter().enumerate() {
1346                         if htlc.htlc_id == htlc_id_arg {
1347                                 match htlc.state {
1348                                         InboundHTLCState::Committed => {},
1349                                         InboundHTLCState::LocalRemoved(_) => {
1350                                                 debug_assert!(false, "Tried to fail an HTLC that was already fail/fulfilled");
1351                                                 return Ok(None);
1352                                         },
1353                                         _ => {
1354                                                 debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
1355                                                 return Err(ChannelError::Ignore(format!("Unable to find a pending HTLC which matched the given HTLC ID ({})", htlc.htlc_id)));
1356                                         }
1357                                 }
1358                                 pending_idx = idx;
1359                         }
1360                 }
1361                 if pending_idx == core::usize::MAX {
1362                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
1363                 }
1364
1365                 // Now update local state:
1366                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
1367                         for pending_update in self.holding_cell_htlc_updates.iter() {
1368                                 match pending_update {
1369                                         &HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
1370                                                 if htlc_id_arg == htlc_id {
1371                                                         debug_assert!(false, "Tried to fail an HTLC that was already fulfilled");
1372                                                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
1373                                                 }
1374                                         },
1375                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
1376                                                 if htlc_id_arg == htlc_id {
1377                                                         debug_assert!(false, "Tried to fail an HTLC that was already failed");
1378                                                         return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
1379                                                 }
1380                                         },
1381                                         _ => {}
1382                                 }
1383                         }
1384                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::FailHTLC {
1385                                 htlc_id: htlc_id_arg,
1386                                 err_packet,
1387                         });
1388                         return Ok(None);
1389                 }
1390
1391                 {
1392                         let htlc = &mut self.pending_inbound_htlcs[pending_idx];
1393                         htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(err_packet.clone()));
1394                 }
1395
1396                 Ok(Some(msgs::UpdateFailHTLC {
1397                         channel_id: self.channel_id(),
1398                         htlc_id: htlc_id_arg,
1399                         reason: err_packet
1400                 }))
1401         }
1402
1403         // Message handlers:
1404
1405         pub fn accept_channel(&mut self, msg: &msgs::AcceptChannel, config: &UserConfig, their_features: InitFeatures) -> Result<(), ChannelError> {
1406                 // Check sanity of message fields:
1407                 if !self.is_outbound() {
1408                         return Err(ChannelError::Close("Got an accept_channel message from an inbound peer".to_owned()));
1409                 }
1410                 if self.channel_state != ChannelState::OurInitSent as u32 {
1411                         return Err(ChannelError::Close("Got an accept_channel message at a strange time".to_owned()));
1412                 }
1413                 if msg.dust_limit_satoshis > 21000000 * 100000000 {
1414                         return Err(ChannelError::Close(format!("Peer never wants payout outputs? dust_limit_satoshis was {}", msg.dust_limit_satoshis)));
1415                 }
1416                 if msg.channel_reserve_satoshis > self.channel_value_satoshis {
1417                         return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must not be greater than ({})", msg.channel_reserve_satoshis, self.channel_value_satoshis)));
1418                 }
1419                 if msg.dust_limit_satoshis > msg.channel_reserve_satoshis {
1420                         return Err(ChannelError::Close(format!("Bogus channel_reserve ({}) and dust_limit ({})", msg.channel_reserve_satoshis, msg.dust_limit_satoshis)));
1421                 }
1422                 if msg.channel_reserve_satoshis < self.holder_dust_limit_satoshis {
1423                         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)));
1424                 }
1425                 let remote_reserve = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis);
1426                 if msg.dust_limit_satoshis > remote_reserve {
1427                         return Err(ChannelError::Close(format!("Dust limit ({}) is bigger than our channel reserve ({})", msg.dust_limit_satoshis, remote_reserve)));
1428                 }
1429                 let full_channel_value_msat = (self.channel_value_satoshis - msg.channel_reserve_satoshis) * 1000;
1430                 if msg.htlc_minimum_msat >= full_channel_value_msat {
1431                         return Err(ChannelError::Close(format!("Minimum htlc value ({}) is full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat)));
1432                 }
1433                 let max_delay_acceptable = u16::min(config.peer_channel_config_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
1434                 if msg.to_self_delay > max_delay_acceptable {
1435                         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)));
1436                 }
1437                 if msg.max_accepted_htlcs < 1 {
1438                         return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel".to_owned()));
1439                 }
1440                 if msg.max_accepted_htlcs > MAX_HTLCS {
1441                         return Err(ChannelError::Close(format!("max_accepted_htlcs was {}. It must not be larger than {}", msg.max_accepted_htlcs, MAX_HTLCS)));
1442                 }
1443
1444                 // Now check against optional parameters as set by config...
1445                 if msg.htlc_minimum_msat > config.peer_channel_config_limits.max_htlc_minimum_msat {
1446                         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)));
1447                 }
1448                 if msg.max_htlc_value_in_flight_msat < config.peer_channel_config_limits.min_max_htlc_value_in_flight_msat {
1449                         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)));
1450                 }
1451                 if msg.channel_reserve_satoshis > config.peer_channel_config_limits.max_channel_reserve_satoshis {
1452                         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)));
1453                 }
1454                 if msg.max_accepted_htlcs < config.peer_channel_config_limits.min_max_accepted_htlcs {
1455                         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)));
1456                 }
1457                 if msg.dust_limit_satoshis < MIN_DUST_LIMIT_SATOSHIS {
1458                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the implementation limit ({})", msg.dust_limit_satoshis, MIN_DUST_LIMIT_SATOSHIS)));
1459                 }
1460                 if msg.dust_limit_satoshis > MAX_DUST_LIMIT_SATOSHIS {
1461                         return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the implementation limit ({})", msg.dust_limit_satoshis, MAX_DUST_LIMIT_SATOSHIS)));
1462                 }
1463                 if msg.minimum_depth > config.peer_channel_config_limits.max_minimum_depth {
1464                         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)));
1465                 }
1466
1467                 let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() {
1468                         match &msg.shutdown_scriptpubkey {
1469                                 &OptionalField::Present(ref script) => {
1470                                         // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything
1471                                         if script.len() == 0 {
1472                                                 None
1473                                         // Peer is signaling upfront_shutdown and has provided a non-accepted scriptpubkey format. Fail the channel
1474                                         } else if is_unsupported_shutdown_script(&their_features, script) {
1475                                                 return Err(ChannelError::Close(format!("Peer is signaling upfront_shutdown but has provided a non-accepted scriptpubkey format. script: ({})", script.to_bytes().to_hex())));
1476                                         } else {
1477                                                 Some(script.clone())
1478                                         }
1479                                 },
1480                                 // 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
1481                                 &OptionalField::Absent => {
1482                                         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()));
1483                                 }
1484                         }
1485                 } else { None };
1486
1487                 self.counterparty_dust_limit_satoshis = msg.dust_limit_satoshis;
1488                 self.counterparty_max_htlc_value_in_flight_msat = cmp::min(msg.max_htlc_value_in_flight_msat, self.channel_value_satoshis * 1000);
1489                 self.counterparty_selected_channel_reserve_satoshis = msg.channel_reserve_satoshis;
1490                 self.counterparty_htlc_minimum_msat = msg.htlc_minimum_msat;
1491                 self.counterparty_max_accepted_htlcs = msg.max_accepted_htlcs;
1492                 self.minimum_depth = msg.minimum_depth;
1493
1494                 let counterparty_pubkeys = ChannelPublicKeys {
1495                         funding_pubkey: msg.funding_pubkey,
1496                         revocation_basepoint: msg.revocation_basepoint,
1497                         payment_point: msg.payment_point,
1498                         delayed_payment_basepoint: msg.delayed_payment_basepoint,
1499                         htlc_basepoint: msg.htlc_basepoint
1500                 };
1501
1502                 self.channel_transaction_parameters.counterparty_parameters = Some(CounterpartyChannelTransactionParameters {
1503                         selected_contest_delay: msg.to_self_delay,
1504                         pubkeys: counterparty_pubkeys,
1505                 });
1506
1507                 self.counterparty_cur_commitment_point = Some(msg.first_per_commitment_point);
1508                 self.counterparty_shutdown_scriptpubkey = counterparty_shutdown_scriptpubkey;
1509
1510                 self.channel_state = ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32;
1511
1512                 Ok(())
1513         }
1514
1515         fn funding_created_signature<L: Deref>(&mut self, sig: &Signature, logger: &L) -> Result<(Txid, CommitmentTransaction, Signature), ChannelError> where L::Target: Logger {
1516                 let funding_script = self.get_funding_redeemscript();
1517
1518                 let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number)?;
1519                 let initial_commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, false, self.feerate_per_kw, logger).0;
1520                 {
1521                         let trusted_tx = initial_commitment_tx.trust();
1522                         let initial_commitment_bitcoin_tx = trusted_tx.built_transaction();
1523                         let sighash = initial_commitment_bitcoin_tx.get_sighash_all(&funding_script, self.channel_value_satoshis);
1524                         // They sign the holder commitment transaction...
1525                         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));
1526                         secp_check!(self.secp_ctx.verify(&sighash, &sig, self.counterparty_funding_pubkey()), "Invalid funding_created signature from peer".to_owned());
1527                 }
1528
1529                 let counterparty_keys = self.build_remote_transaction_keys()?;
1530                 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;
1531
1532                 let counterparty_trusted_tx = counterparty_initial_commitment_tx.trust();
1533                 let counterparty_initial_bitcoin_tx = counterparty_trusted_tx.built_transaction();
1534                 log_trace!(logger, "Initial counterparty ID {} tx {}", counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
1535
1536                 let counterparty_signature = self.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, &self.secp_ctx)
1537                                 .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0;
1538
1539                 // We sign "counterparty" commitment transaction, allowing them to broadcast the tx if they wish.
1540                 Ok((counterparty_initial_bitcoin_tx.txid, initial_commitment_tx, counterparty_signature))
1541         }
1542
1543         fn counterparty_funding_pubkey(&self) -> &PublicKey {
1544                 &self.get_counterparty_pubkeys().funding_pubkey
1545         }
1546
1547         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 {
1548                 if self.is_outbound() {
1549                         return Err(ChannelError::Close("Received funding_created for an outbound channel?".to_owned()));
1550                 }
1551                 if self.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
1552                         // BOLT 2 says that if we disconnect before we send funding_signed we SHOULD NOT
1553                         // remember the channel, so it's safe to just send an error_message here and drop the
1554                         // channel.
1555                         return Err(ChannelError::Close("Received funding_created after we got the channel!".to_owned()));
1556                 }
1557                 if self.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
1558                                 self.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
1559                                 self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
1560                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
1561                 }
1562
1563                 let funding_txo = OutPoint { txid: msg.funding_txid, index: msg.funding_output_index };
1564                 self.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
1565                 // This is an externally observable change before we finish all our checks.  In particular
1566                 // funding_created_signature may fail.
1567                 self.holder_signer.ready_channel(&self.channel_transaction_parameters);
1568
1569                 let (counterparty_initial_commitment_txid, initial_commitment_tx, signature) = match self.funding_created_signature(&msg.signature, logger) {
1570                         Ok(res) => res,
1571                         Err(ChannelError::Close(e)) => {
1572                                 self.channel_transaction_parameters.funding_outpoint = None;
1573                                 return Err(ChannelError::Close(e));
1574                         },
1575                         Err(e) => {
1576                                 // The only error we know how to handle is ChannelError::Close, so we fall over here
1577                                 // to make sure we don't continue with an inconsistent state.
1578                                 panic!("unexpected error type from funding_created_signature {:?}", e);
1579                         }
1580                 };
1581
1582                 let holder_commitment_tx = HolderCommitmentTransaction::new(
1583                         initial_commitment_tx,
1584                         msg.signature,
1585                         Vec::new(),
1586                         &self.get_holder_pubkeys().funding_pubkey,
1587                         self.counterparty_funding_pubkey()
1588                 );
1589
1590                 // Now that we're past error-generating stuff, update our local state:
1591
1592                 let funding_redeemscript = self.get_funding_redeemscript();
1593                 let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
1594                 let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound());
1595                 let channel_monitor = ChannelMonitor::new(self.secp_ctx.clone(), self.holder_signer.clone(),
1596                                                           &self.shutdown_pubkey, self.get_holder_selected_contest_delay(),
1597                                                           &self.destination_script, (funding_txo, funding_txo_script.clone()),
1598                                                           &self.channel_transaction_parameters,
1599                                                           funding_redeemscript.clone(), self.channel_value_satoshis,
1600                                                           obscure_factor,
1601                                                           holder_commitment_tx, best_block);
1602
1603                 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);
1604
1605                 self.channel_state = ChannelState::FundingSent as u32;
1606                 self.channel_id = funding_txo.to_channel_id();
1607                 self.cur_counterparty_commitment_transaction_number -= 1;
1608                 self.cur_holder_commitment_transaction_number -= 1;
1609
1610                 Ok((msgs::FundingSigned {
1611                         channel_id: self.channel_id,
1612                         signature
1613                 }, channel_monitor))
1614         }
1615
1616         /// Handles a funding_signed message from the remote end.
1617         /// If this call is successful, broadcast the funding transaction (and not before!)
1618         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 {
1619                 if !self.is_outbound() {
1620                         return Err(ChannelError::Close("Received funding_signed for an inbound channel?".to_owned()));
1621                 }
1622                 if self.channel_state & !(ChannelState::MonitorUpdateFailed as u32) != ChannelState::FundingCreated as u32 {
1623                         return Err(ChannelError::Close("Received funding_signed in strange state!".to_owned()));
1624                 }
1625                 if self.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
1626                                 self.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
1627                                 self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
1628                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
1629                 }
1630
1631                 let funding_script = self.get_funding_redeemscript();
1632
1633                 let counterparty_keys = self.build_remote_transaction_keys()?;
1634                 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;
1635                 let counterparty_trusted_tx = counterparty_initial_commitment_tx.trust();
1636                 let counterparty_initial_bitcoin_tx = counterparty_trusted_tx.built_transaction();
1637
1638                 log_trace!(logger, "Initial counterparty ID {} tx {}", counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
1639
1640                 let holder_signer = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number)?;
1641                 let initial_commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &holder_signer, true, false, self.feerate_per_kw, logger).0;
1642                 {
1643                         let trusted_tx = initial_commitment_tx.trust();
1644                         let initial_commitment_bitcoin_tx = trusted_tx.built_transaction();
1645                         let sighash = initial_commitment_bitcoin_tx.get_sighash_all(&funding_script, self.channel_value_satoshis);
1646                         // They sign our commitment transaction, allowing us to broadcast the tx if we wish.
1647                         if let Err(_) = self.secp_ctx.verify(&sighash, &msg.signature, &self.get_counterparty_pubkeys().funding_pubkey) {
1648                                 return Err(ChannelError::Close("Invalid funding_signed signature from peer".to_owned()));
1649                         }
1650                 }
1651
1652                 let holder_commitment_tx = HolderCommitmentTransaction::new(
1653                         initial_commitment_tx,
1654                         msg.signature,
1655                         Vec::new(),
1656                         &self.get_holder_pubkeys().funding_pubkey,
1657                         self.counterparty_funding_pubkey()
1658                 );
1659
1660
1661                 let funding_redeemscript = self.get_funding_redeemscript();
1662                 let funding_txo = self.get_funding_txo().unwrap();
1663                 let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
1664                 let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound());
1665                 let channel_monitor = ChannelMonitor::new(self.secp_ctx.clone(), self.holder_signer.clone(),
1666                                                           &self.shutdown_pubkey, self.get_holder_selected_contest_delay(),
1667                                                           &self.destination_script, (funding_txo, funding_txo_script),
1668                                                           &self.channel_transaction_parameters,
1669                                                           funding_redeemscript.clone(), self.channel_value_satoshis,
1670                                                           obscure_factor,
1671                                                           holder_commitment_tx, best_block);
1672
1673                 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);
1674
1675                 assert_eq!(self.channel_state & (ChannelState::MonitorUpdateFailed as u32), 0); // We have no had any monitor(s) yet to fail update!
1676                 self.channel_state = ChannelState::FundingSent as u32;
1677                 self.cur_holder_commitment_transaction_number -= 1;
1678                 self.cur_counterparty_commitment_transaction_number -= 1;
1679
1680                 Ok((channel_monitor, self.funding_transaction.as_ref().cloned().unwrap()))
1681         }
1682
1683         pub fn funding_locked(&mut self, msg: &msgs::FundingLocked) -> Result<(), ChannelError> {
1684                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
1685                         return Err(ChannelError::Close("Peer sent funding_locked when we needed a channel_reestablish".to_owned()));
1686                 }
1687
1688                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
1689
1690                 if non_shutdown_state == ChannelState::FundingSent as u32 {
1691                         self.channel_state |= ChannelState::TheirFundingLocked as u32;
1692                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) {
1693                         self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
1694                         self.update_time_counter += 1;
1695                 } else if (self.channel_state & (ChannelState::ChannelFunded as u32) != 0 &&
1696                                  // Note that funding_signed/funding_created will have decremented both by 1!
1697                                  self.cur_holder_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1 &&
1698                                  self.cur_counterparty_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1) ||
1699                                 // If we reconnected before sending our funding locked they may still resend theirs:
1700                                 (self.channel_state & (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32) ==
1701                                                       (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32)) {
1702                         if self.counterparty_cur_commitment_point != Some(msg.next_per_commitment_point) {
1703                                 return Err(ChannelError::Close("Peer sent a reconnect funding_locked with a different point".to_owned()));
1704                         }
1705                         // They probably disconnected/reconnected and re-sent the funding_locked, which is required
1706                         return Ok(());
1707                 } else {
1708                         return Err(ChannelError::Close("Peer sent a funding_locked at a strange time".to_owned()));
1709                 }
1710
1711                 self.counterparty_prev_commitment_point = self.counterparty_cur_commitment_point;
1712                 self.counterparty_cur_commitment_point = Some(msg.next_per_commitment_point);
1713                 Ok(())
1714         }
1715
1716         /// Returns (inbound_htlc_count, htlc_inbound_value_msat)
1717         fn get_inbound_pending_htlc_stats(&self) -> (u32, u64) {
1718                 let mut htlc_inbound_value_msat = 0;
1719                 for ref htlc in self.pending_inbound_htlcs.iter() {
1720                         htlc_inbound_value_msat += htlc.amount_msat;
1721                 }
1722                 (self.pending_inbound_htlcs.len() as u32, htlc_inbound_value_msat)
1723         }
1724
1725         /// Returns (outbound_htlc_count, htlc_outbound_value_msat) *including* pending adds in our
1726         /// holding cell.
1727         fn get_outbound_pending_htlc_stats(&self) -> (u32, u64) {
1728                 let mut htlc_outbound_value_msat = 0;
1729                 for ref htlc in self.pending_outbound_htlcs.iter() {
1730                         htlc_outbound_value_msat += htlc.amount_msat;
1731                 }
1732
1733                 let mut htlc_outbound_count = self.pending_outbound_htlcs.len();
1734                 for update in self.holding_cell_htlc_updates.iter() {
1735                         if let &HTLCUpdateAwaitingACK::AddHTLC { ref amount_msat, .. } = update {
1736                                 htlc_outbound_count += 1;
1737                                 htlc_outbound_value_msat += amount_msat;
1738                         }
1739                 }
1740
1741                 (htlc_outbound_count as u32, htlc_outbound_value_msat)
1742         }
1743
1744         /// Get the available (ie not including pending HTLCs) inbound and outbound balance in msat.
1745         /// Doesn't bother handling the
1746         /// if-we-removed-it-already-but-haven't-fully-resolved-they-can-still-send-an-inbound-HTLC
1747         /// corner case properly.
1748         pub fn get_inbound_outbound_available_balance_msat(&self) -> (u64, u64) {
1749                 // Note that we have to handle overflow due to the above case.
1750                 (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,
1751                 cmp::max(self.value_to_self_msat as i64 - self.get_outbound_pending_htlc_stats().1 as i64, 0) as u64)
1752         }
1753
1754         // Get the fee cost of a commitment tx with a given number of HTLC outputs.
1755         // Note that num_htlcs should not include dust HTLCs.
1756         fn commit_tx_fee_msat(&self, num_htlcs: usize) -> u64 {
1757                 // Note that we need to divide before multiplying to round properly,
1758                 // since the lowest denomination of bitcoin on-chain is the satoshi.
1759                 (COMMITMENT_TX_BASE_WEIGHT + num_htlcs as u64 * COMMITMENT_TX_WEIGHT_PER_HTLC) * self.feerate_per_kw as u64 / 1000 * 1000
1760         }
1761
1762         // Get the commitment tx fee for the local's (i.e. our) next commitment transaction based on the
1763         // number of pending HTLCs that are on track to be in our next commitment tx, plus an additional
1764         // HTLC if `fee_spike_buffer_htlc` is Some, plus a new HTLC given by `new_htlc_amount`. Dust HTLCs
1765         // are excluded.
1766         fn next_local_commit_tx_fee_msat(&self, htlc: HTLCCandidate, fee_spike_buffer_htlc: Option<()>) -> u64 {
1767                 assert!(self.is_outbound());
1768
1769                 let real_dust_limit_success_sat = (self.feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
1770                 let real_dust_limit_timeout_sat = (self.feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
1771
1772                 let mut addl_htlcs = 0;
1773                 if fee_spike_buffer_htlc.is_some() { addl_htlcs += 1; }
1774                 match htlc.origin {
1775                         HTLCInitiator::LocalOffered => {
1776                                 if htlc.amount_msat / 1000 >= real_dust_limit_timeout_sat {
1777                                         addl_htlcs += 1;
1778                                 }
1779                         },
1780                         HTLCInitiator::RemoteOffered => {
1781                                 if htlc.amount_msat / 1000 >= real_dust_limit_success_sat {
1782                                         addl_htlcs += 1;
1783                                 }
1784                         }
1785                 }
1786
1787                 let mut included_htlcs = 0;
1788                 for ref htlc in self.pending_inbound_htlcs.iter() {
1789                         if htlc.amount_msat / 1000 < real_dust_limit_success_sat {
1790                                 continue
1791                         }
1792                         // We include LocalRemoved HTLCs here because we may still need to broadcast a commitment
1793                         // transaction including this HTLC if it times out before they RAA.
1794                         included_htlcs += 1;
1795                 }
1796
1797                 for ref htlc in self.pending_outbound_htlcs.iter() {
1798                         if htlc.amount_msat / 1000 < real_dust_limit_timeout_sat {
1799                                 continue
1800                         }
1801                         match htlc.state {
1802                                 OutboundHTLCState::LocalAnnounced {..} => included_htlcs += 1,
1803                                 OutboundHTLCState::Committed => included_htlcs += 1,
1804                                 OutboundHTLCState::RemoteRemoved {..} => included_htlcs += 1,
1805                                 // We don't include AwaitingRemoteRevokeToRemove HTLCs because our next commitment
1806                                 // transaction won't be generated until they send us their next RAA, which will mean
1807                                 // dropping any HTLCs in this state.
1808                                 _ => {},
1809                         }
1810                 }
1811
1812                 for htlc in self.holding_cell_htlc_updates.iter() {
1813                         match htlc {
1814                                 &HTLCUpdateAwaitingACK::AddHTLC { amount_msat, .. } => {
1815                                         if amount_msat / 1000 < real_dust_limit_timeout_sat {
1816                                                 continue
1817                                         }
1818                                         included_htlcs += 1
1819                                 },
1820                                 _ => {}, // Don't include claims/fails that are awaiting ack, because once we get the
1821                                          // ack we're guaranteed to never include them in commitment txs anymore.
1822                         }
1823                 }
1824
1825                 let num_htlcs = included_htlcs + addl_htlcs;
1826                 let res = self.commit_tx_fee_msat(num_htlcs);
1827                 #[cfg(any(test, feature = "fuzztarget"))]
1828                 {
1829                         let mut fee = res;
1830                         if fee_spike_buffer_htlc.is_some() {
1831                                 fee = self.commit_tx_fee_msat(num_htlcs - 1);
1832                         }
1833                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len()
1834                                 + self.holding_cell_htlc_updates.len();
1835                         let commitment_tx_info = CommitmentTxInfoCached {
1836                                 fee,
1837                                 total_pending_htlcs,
1838                                 next_holder_htlc_id: match htlc.origin {
1839                                         HTLCInitiator::LocalOffered => self.next_holder_htlc_id + 1,
1840                                         HTLCInitiator::RemoteOffered => self.next_holder_htlc_id,
1841                                 },
1842                                 next_counterparty_htlc_id: match htlc.origin {
1843                                         HTLCInitiator::LocalOffered => self.next_counterparty_htlc_id,
1844                                         HTLCInitiator::RemoteOffered => self.next_counterparty_htlc_id + 1,
1845                                 },
1846                                 feerate: self.feerate_per_kw,
1847                         };
1848                         *self.next_local_commitment_tx_fee_info_cached.lock().unwrap() = Some(commitment_tx_info);
1849                 }
1850                 res
1851         }
1852
1853         // Get the commitment tx fee for the remote's next commitment transaction based on the number of
1854         // pending HTLCs that are on track to be in their next commitment tx, plus an additional HTLC if
1855         // `fee_spike_buffer_htlc` is Some, plus a new HTLC given by `new_htlc_amount`. Dust HTLCs are
1856         // excluded.
1857         fn next_remote_commit_tx_fee_msat(&self, htlc: HTLCCandidate, fee_spike_buffer_htlc: Option<()>) -> u64 {
1858                 assert!(!self.is_outbound());
1859
1860                 let real_dust_limit_success_sat = (self.feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
1861                 let real_dust_limit_timeout_sat = (self.feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + self.counterparty_dust_limit_satoshis;
1862
1863                 let mut addl_htlcs = 0;
1864                 if fee_spike_buffer_htlc.is_some() { addl_htlcs += 1; }
1865                 match htlc.origin {
1866                         HTLCInitiator::LocalOffered => {
1867                                 if htlc.amount_msat / 1000 >= real_dust_limit_success_sat {
1868                                         addl_htlcs += 1;
1869                                 }
1870                         },
1871                         HTLCInitiator::RemoteOffered => {
1872                                 if htlc.amount_msat / 1000 >= real_dust_limit_timeout_sat {
1873                                         addl_htlcs += 1;
1874                                 }
1875                         }
1876                 }
1877
1878                 // When calculating the set of HTLCs which will be included in their next commitment_signed, all
1879                 // non-dust inbound HTLCs are included (as all states imply it will be included) and only
1880                 // committed outbound HTLCs, see below.
1881                 let mut included_htlcs = 0;
1882                 for ref htlc in self.pending_inbound_htlcs.iter() {
1883                         if htlc.amount_msat / 1000 <= real_dust_limit_timeout_sat {
1884                                 continue
1885                         }
1886                         included_htlcs += 1;
1887                 }
1888
1889                 for ref htlc in self.pending_outbound_htlcs.iter() {
1890                         if htlc.amount_msat / 1000 <= real_dust_limit_success_sat {
1891                                 continue
1892                         }
1893                         // We only include outbound HTLCs if it will not be included in their next commitment_signed,
1894                         // i.e. if they've responded to us with an RAA after announcement.
1895                         match htlc.state {
1896                                 OutboundHTLCState::Committed => included_htlcs += 1,
1897                                 OutboundHTLCState::RemoteRemoved {..} => included_htlcs += 1,
1898                                 OutboundHTLCState::LocalAnnounced { .. } => included_htlcs += 1,
1899                                 _ => {},
1900                         }
1901                 }
1902
1903                 let num_htlcs = included_htlcs + addl_htlcs;
1904                 let res = self.commit_tx_fee_msat(num_htlcs);
1905                 #[cfg(any(test, feature = "fuzztarget"))]
1906                 {
1907                         let mut fee = res;
1908                         if fee_spike_buffer_htlc.is_some() {
1909                                 fee = self.commit_tx_fee_msat(num_htlcs - 1);
1910                         }
1911                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len();
1912                         let commitment_tx_info = CommitmentTxInfoCached {
1913                                 fee,
1914                                 total_pending_htlcs,
1915                                 next_holder_htlc_id: match htlc.origin {
1916                                         HTLCInitiator::LocalOffered => self.next_holder_htlc_id + 1,
1917                                         HTLCInitiator::RemoteOffered => self.next_holder_htlc_id,
1918                                 },
1919                                 next_counterparty_htlc_id: match htlc.origin {
1920                                         HTLCInitiator::LocalOffered => self.next_counterparty_htlc_id,
1921                                         HTLCInitiator::RemoteOffered => self.next_counterparty_htlc_id + 1,
1922                                 },
1923                                 feerate: self.feerate_per_kw,
1924                         };
1925                         *self.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = Some(commitment_tx_info);
1926                 }
1927                 res
1928         }
1929
1930         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>
1931         where F: for<'a> Fn(&'a Self, PendingHTLCStatus, u16) -> PendingHTLCStatus, L::Target: Logger {
1932                 // We can't accept HTLCs sent after we've sent a shutdown.
1933                 let local_sent_shutdown = (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::LocalShutdownSent as u32)) != (ChannelState::ChannelFunded as u32);
1934                 if local_sent_shutdown {
1935                         pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|20);
1936                 }
1937                 // If the remote has sent a shutdown prior to adding this HTLC, then they are in violation of the spec.
1938                 let remote_sent_shutdown = (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::RemoteShutdownSent as u32)) != (ChannelState::ChannelFunded as u32);
1939                 if remote_sent_shutdown {
1940                         return Err(ChannelError::Close("Got add HTLC message when channel was not in an operational state".to_owned()));
1941                 }
1942                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
1943                         return Err(ChannelError::Close("Peer sent update_add_htlc when we needed a channel_reestablish".to_owned()));
1944                 }
1945                 if msg.amount_msat > self.channel_value_satoshis * 1000 {
1946                         return Err(ChannelError::Close("Remote side tried to send more than the total value of the channel".to_owned()));
1947                 }
1948                 if msg.amount_msat == 0 {
1949                         return Err(ChannelError::Close("Remote side tried to send a 0-msat HTLC".to_owned()));
1950                 }
1951                 if msg.amount_msat < self.holder_htlc_minimum_msat {
1952                         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)));
1953                 }
1954
1955                 let (inbound_htlc_count, htlc_inbound_value_msat) = self.get_inbound_pending_htlc_stats();
1956                 if inbound_htlc_count + 1 > OUR_MAX_HTLCS as u32 {
1957                         return Err(ChannelError::Close(format!("Remote tried to push more than our max accepted HTLCs ({})", OUR_MAX_HTLCS)));
1958                 }
1959                 let holder_max_htlc_value_in_flight_msat = Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis);
1960                 if htlc_inbound_value_msat + msg.amount_msat > holder_max_htlc_value_in_flight_msat {
1961                         return Err(ChannelError::Close(format!("Remote HTLC add would put them over our max HTLC value ({})", holder_max_htlc_value_in_flight_msat)));
1962                 }
1963                 // Check holder_selected_channel_reserve_satoshis (we're getting paid, so they have to at least meet
1964                 // the reserve_satoshis we told them to always have as direct payment so that they lose
1965                 // something if we punish them for broadcasting an old state).
1966                 // Note that we don't really care about having a small/no to_remote output in our local
1967                 // commitment transactions, as the purpose of the channel reserve is to ensure we can
1968                 // punish *them* if they misbehave, so we discount any outbound HTLCs which will not be
1969                 // present in the next commitment transaction we send them (at least for fulfilled ones,
1970                 // failed ones won't modify value_to_self).
1971                 // Note that we will send HTLCs which another instance of rust-lightning would think
1972                 // violate the reserve value if we do not do this (as we forget inbound HTLCs from the
1973                 // Channel state once they will not be present in the next received commitment
1974                 // transaction).
1975                 let mut removed_outbound_total_msat = 0;
1976                 for ref htlc in self.pending_outbound_htlcs.iter() {
1977                         if let OutboundHTLCState::AwaitingRemoteRevokeToRemove(None) = htlc.state {
1978                                 removed_outbound_total_msat += htlc.amount_msat;
1979                         } else if let OutboundHTLCState::AwaitingRemovedRemoteRevoke(None) = htlc.state {
1980                                 removed_outbound_total_msat += htlc.amount_msat;
1981                         }
1982                 }
1983
1984                 let pending_value_to_self_msat =
1985                         self.value_to_self_msat + htlc_inbound_value_msat - removed_outbound_total_msat;
1986                 let pending_remote_value_msat =
1987                         self.channel_value_satoshis * 1000 - pending_value_to_self_msat;
1988                 if pending_remote_value_msat < msg.amount_msat {
1989                         return Err(ChannelError::Close("Remote HTLC add would overdraw remaining funds".to_owned()));
1990                 }
1991
1992                 // Check that the remote can afford to pay for this HTLC on-chain at the current
1993                 // feerate_per_kw, while maintaining their channel reserve (as required by the spec).
1994                 let remote_commit_tx_fee_msat = if self.is_outbound() { 0 } else {
1995                         let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
1996                         self.next_remote_commit_tx_fee_msat(htlc_candidate, None) // Don't include the extra fee spike buffer HTLC in calculations
1997                 };
1998                 if pending_remote_value_msat - msg.amount_msat < remote_commit_tx_fee_msat {
1999                         return Err(ChannelError::Close("Remote HTLC add would not leave enough to pay for fees".to_owned()));
2000                 };
2001
2002                 let chan_reserve_msat =
2003                         Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis) * 1000;
2004                 if pending_remote_value_msat - msg.amount_msat - remote_commit_tx_fee_msat < chan_reserve_msat {
2005                         return Err(ChannelError::Close("Remote HTLC add would put them under remote reserve value".to_owned()));
2006                 }
2007
2008                 if !self.is_outbound() {
2009                         // `2 *` and `Some(())` is for the fee spike buffer we keep for the remote. This deviates from
2010                         // the spec because in the spec, the fee spike buffer requirement doesn't exist on the
2011                         // receiver's side, only on the sender's.
2012                         // Note that when we eventually remove support for fee updates and switch to anchor output
2013                         // fees, we will drop the `2 *`, since we no longer be as sensitive to fee spikes. But, keep
2014                         // the extra htlc when calculating the next remote commitment transaction fee as we should
2015                         // still be able to afford adding this HTLC plus one more future HTLC, regardless of being
2016                         // sensitive to fee spikes.
2017                         let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
2018                         let remote_fee_cost_incl_stuck_buffer_msat = 2 * self.next_remote_commit_tx_fee_msat(htlc_candidate, Some(()));
2019                         if pending_remote_value_msat - msg.amount_msat - chan_reserve_msat < remote_fee_cost_incl_stuck_buffer_msat {
2020                                 // Note that if the pending_forward_status is not updated here, then it's because we're already failing
2021                                 // the HTLC, i.e. its status is already set to failing.
2022                                 log_info!(logger, "Attempting to fail HTLC due to fee spike buffer violation");
2023                                 pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x1000|7);
2024                         }
2025                 } else {
2026                         // Check that they won't violate our local required channel reserve by adding this HTLC.
2027                         let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
2028                         let local_commit_tx_fee_msat = self.next_local_commit_tx_fee_msat(htlc_candidate, None);
2029                         if self.value_to_self_msat < self.counterparty_selected_channel_reserve_satoshis * 1000 + local_commit_tx_fee_msat {
2030                                 return Err(ChannelError::Close("Cannot accept HTLC that would put our balance under counterparty-announced channel reserve value".to_owned()));
2031                         }
2032                 }
2033                 if self.next_counterparty_htlc_id != msg.htlc_id {
2034                         return Err(ChannelError::Close(format!("Remote skipped HTLC ID (skipped ID: {})", self.next_counterparty_htlc_id)));
2035                 }
2036                 if msg.cltv_expiry >= 500000000 {
2037                         return Err(ChannelError::Close("Remote provided CLTV expiry in seconds instead of block height".to_owned()));
2038                 }
2039
2040                 if self.channel_state & ChannelState::LocalShutdownSent as u32 != 0 {
2041                         if let PendingHTLCStatus::Forward(_) = pending_forward_status {
2042                                 panic!("ChannelManager shouldn't be trying to add a forwardable HTLC after we've started closing");
2043                         }
2044                 }
2045
2046                 // Now update local state:
2047                 self.next_counterparty_htlc_id += 1;
2048                 self.pending_inbound_htlcs.push(InboundHTLCOutput {
2049                         htlc_id: msg.htlc_id,
2050                         amount_msat: msg.amount_msat,
2051                         payment_hash: msg.payment_hash,
2052                         cltv_expiry: msg.cltv_expiry,
2053                         state: InboundHTLCState::RemoteAnnounced(pending_forward_status),
2054                 });
2055                 Ok(())
2056         }
2057
2058         /// Marks an outbound HTLC which we have received update_fail/fulfill/malformed
2059         #[inline]
2060         fn mark_outbound_htlc_removed(&mut self, htlc_id: u64, check_preimage: Option<PaymentHash>, fail_reason: Option<HTLCFailReason>) -> Result<&HTLCSource, ChannelError> {
2061                 for htlc in self.pending_outbound_htlcs.iter_mut() {
2062                         if htlc.htlc_id == htlc_id {
2063                                 match check_preimage {
2064                                         None => {},
2065                                         Some(payment_hash) =>
2066                                                 if payment_hash != htlc.payment_hash {
2067                                                         return Err(ChannelError::Close(format!("Remote tried to fulfill HTLC ({}) with an incorrect preimage", htlc_id)));
2068                                                 }
2069                                 };
2070                                 match htlc.state {
2071                                         OutboundHTLCState::LocalAnnounced(_) =>
2072                                                 return Err(ChannelError::Close(format!("Remote tried to fulfill/fail HTLC ({}) before it had been committed", htlc_id))),
2073                                         OutboundHTLCState::Committed => {
2074                                                 htlc.state = OutboundHTLCState::RemoteRemoved(fail_reason);
2075                                         },
2076                                         OutboundHTLCState::AwaitingRemoteRevokeToRemove(_) | OutboundHTLCState::AwaitingRemovedRemoteRevoke(_) | OutboundHTLCState::RemoteRemoved(_) =>
2077                                                 return Err(ChannelError::Close(format!("Remote tried to fulfill/fail HTLC ({}) that they'd already fulfilled/failed", htlc_id))),
2078                                 }
2079                                 return Ok(&htlc.source);
2080                         }
2081                 }
2082                 Err(ChannelError::Close("Remote tried to fulfill/fail an HTLC we couldn't find".to_owned()))
2083         }
2084
2085         pub fn update_fulfill_htlc(&mut self, msg: &msgs::UpdateFulfillHTLC) -> Result<HTLCSource, ChannelError> {
2086                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2087                         return Err(ChannelError::Close("Got fulfill HTLC message when channel was not in an operational state".to_owned()));
2088                 }
2089                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2090                         return Err(ChannelError::Close("Peer sent update_fulfill_htlc when we needed a channel_reestablish".to_owned()));
2091                 }
2092
2093                 let payment_hash = PaymentHash(Sha256::hash(&msg.payment_preimage.0[..]).into_inner());
2094                 self.mark_outbound_htlc_removed(msg.htlc_id, Some(payment_hash), None).map(|source| source.clone())
2095         }
2096
2097         pub fn update_fail_htlc(&mut self, msg: &msgs::UpdateFailHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> {
2098                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2099                         return Err(ChannelError::Close("Got fail HTLC message when channel was not in an operational state".to_owned()));
2100                 }
2101                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2102                         return Err(ChannelError::Close("Peer sent update_fail_htlc when we needed a channel_reestablish".to_owned()));
2103                 }
2104
2105                 self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason))?;
2106                 Ok(())
2107         }
2108
2109         pub fn update_fail_malformed_htlc(&mut self, msg: &msgs::UpdateFailMalformedHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> {
2110                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2111                         return Err(ChannelError::Close("Got fail malformed HTLC message when channel was not in an operational state".to_owned()));
2112                 }
2113                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2114                         return Err(ChannelError::Close("Peer sent update_fail_malformed_htlc when we needed a channel_reestablish".to_owned()));
2115                 }
2116
2117                 self.mark_outbound_htlc_removed(msg.htlc_id, None, Some(fail_reason))?;
2118                 Ok(())
2119         }
2120
2121         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)>
2122         where F::Target: FeeEstimator,
2123                                 L::Target: Logger
2124         {
2125                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2126                         return Err((None, ChannelError::Close("Got commitment signed message when channel was not in an operational state".to_owned())));
2127                 }
2128                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2129                         return Err((None, ChannelError::Close("Peer sent commitment_signed when we needed a channel_reestablish".to_owned())));
2130                 }
2131                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() {
2132                         return Err((None, ChannelError::Close("Peer sent commitment_signed after we'd started exchanging closing_signeds".to_owned())));
2133                 }
2134
2135                 let funding_script = self.get_funding_redeemscript();
2136
2137                 let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number).map_err(|e| (None, e))?;
2138
2139                 let mut update_fee = false;
2140                 let feerate_per_kw = if !self.is_outbound() && self.pending_update_fee.is_some() {
2141                         update_fee = true;
2142                         self.pending_update_fee.unwrap()
2143                 } else {
2144                         self.feerate_per_kw
2145                 };
2146
2147                 let (num_htlcs, mut htlcs_cloned, commitment_tx, commitment_txid) = {
2148                         let commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, false, feerate_per_kw, logger);
2149                         let commitment_txid = {
2150                                 let trusted_tx = commitment_tx.0.trust();
2151                                 let bitcoin_tx = trusted_tx.built_transaction();
2152                                 let sighash = bitcoin_tx.get_sighash_all(&funding_script, self.channel_value_satoshis);
2153
2154                                 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));
2155                                 if let Err(_) = self.secp_ctx.verify(&sighash, &msg.signature, &self.counterparty_funding_pubkey()) {
2156                                         return Err((None, ChannelError::Close("Invalid commitment tx signature from peer".to_owned())));
2157                                 }
2158                                 bitcoin_tx.txid
2159                         };
2160                         let htlcs_cloned: Vec<_> = commitment_tx.2.iter().map(|htlc| (htlc.0.clone(), htlc.1.map(|h| h.clone()))).collect();
2161                         (commitment_tx.1, htlcs_cloned, commitment_tx.0, commitment_txid)
2162                 };
2163
2164                 let total_fee = feerate_per_kw as u64 * (COMMITMENT_TX_BASE_WEIGHT + (num_htlcs as u64) * COMMITMENT_TX_WEIGHT_PER_HTLC) / 1000;
2165                 //If channel fee was updated by funder confirm funder can afford the new fee rate when applied to the current local commitment transaction
2166                 if update_fee {
2167                         let counterparty_reserve_we_require = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis);
2168                         if self.channel_value_satoshis - self.value_to_self_msat / 1000 < total_fee + counterparty_reserve_we_require {
2169                                 return Err((None, ChannelError::Close("Funding remote cannot afford proposed new fee".to_owned())));
2170                         }
2171                 }
2172                 #[cfg(any(test, feature = "fuzztarget"))]
2173                 {
2174                         if self.is_outbound() {
2175                                 let projected_commit_tx_info = self.next_local_commitment_tx_fee_info_cached.lock().unwrap().take();
2176                                 *self.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = None;
2177                                 if let Some(info) = projected_commit_tx_info {
2178                                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len()
2179                                                 + self.holding_cell_htlc_updates.len();
2180                                         if info.total_pending_htlcs == total_pending_htlcs
2181                                                 && info.next_holder_htlc_id == self.next_holder_htlc_id
2182                                                 && info.next_counterparty_htlc_id == self.next_counterparty_htlc_id
2183                                                 && info.feerate == self.feerate_per_kw {
2184                                                         assert_eq!(total_fee, info.fee / 1000);
2185                                                 }
2186                                 }
2187                         }
2188                 }
2189
2190                 if msg.htlc_signatures.len() != num_htlcs {
2191                         return Err((None, ChannelError::Close(format!("Got wrong number of HTLC signatures ({}) from remote. It must be {}", msg.htlc_signatures.len(), num_htlcs))));
2192                 }
2193
2194                 // TODO: Sadly, we pass HTLCs twice to ChannelMonitor: once via the HolderCommitmentTransaction and once via the update
2195                 let mut htlcs_and_sigs = Vec::with_capacity(htlcs_cloned.len());
2196                 for (idx, (htlc, source)) in htlcs_cloned.drain(..).enumerate() {
2197                         if let Some(_) = htlc.transaction_output_index {
2198                                 let htlc_tx = self.build_htlc_transaction(&commitment_txid, &htlc, true, &keys, feerate_per_kw);
2199                                 let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys);
2200                                 let htlc_sighash = hash_to_message!(&bip143::SigHashCache::new(&htlc_tx).signature_hash(0, &htlc_redeemscript, htlc.amount_msat / 1000, SigHashType::All)[..]);
2201                                 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));
2202                                 if let Err(_) = self.secp_ctx.verify(&htlc_sighash, &msg.htlc_signatures[idx], &keys.countersignatory_htlc_key) {
2203                                         return Err((None, ChannelError::Close("Invalid HTLC tx signature from peer".to_owned())));
2204                                 }
2205                                 htlcs_and_sigs.push((htlc, Some(msg.htlc_signatures[idx]), source));
2206                         } else {
2207                                 htlcs_and_sigs.push((htlc, None, source));
2208                         }
2209                 }
2210
2211                 let holder_commitment_tx = HolderCommitmentTransaction::new(
2212                         commitment_tx,
2213                         msg.signature,
2214                         msg.htlc_signatures.clone(),
2215                         &self.get_holder_pubkeys().funding_pubkey,
2216                         self.counterparty_funding_pubkey()
2217                 );
2218
2219                 let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number - 1, &self.secp_ctx);
2220                 let per_commitment_secret = self.holder_signer.release_commitment_secret(self.cur_holder_commitment_transaction_number + 1);
2221
2222                 // Update state now that we've passed all the can-fail calls...
2223                 let mut need_commitment = false;
2224                 if !self.is_outbound() {
2225                         if let Some(fee_update) = self.pending_update_fee {
2226                                 self.feerate_per_kw = fee_update;
2227                                 // We later use the presence of pending_update_fee to indicate we should generate a
2228                                 // commitment_signed upon receipt of revoke_and_ack, so we can only set it to None
2229                                 // if we're not awaiting a revoke (ie will send a commitment_signed now).
2230                                 if (self.channel_state & ChannelState::AwaitingRemoteRevoke as u32) == 0 {
2231                                         need_commitment = true;
2232                                         self.pending_update_fee = None;
2233                                 }
2234                         }
2235                 }
2236
2237                 self.latest_monitor_update_id += 1;
2238                 let mut monitor_update = ChannelMonitorUpdate {
2239                         update_id: self.latest_monitor_update_id,
2240                         updates: vec![ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo {
2241                                 commitment_tx: holder_commitment_tx,
2242                                 htlc_outputs: htlcs_and_sigs
2243                         }]
2244                 };
2245
2246                 for htlc in self.pending_inbound_htlcs.iter_mut() {
2247                         let new_forward = if let &InboundHTLCState::RemoteAnnounced(ref forward_info) = &htlc.state {
2248                                 Some(forward_info.clone())
2249                         } else { None };
2250                         if let Some(forward_info) = new_forward {
2251                                 htlc.state = InboundHTLCState::AwaitingRemoteRevokeToAnnounce(forward_info);
2252                                 need_commitment = true;
2253                         }
2254                 }
2255                 for htlc in self.pending_outbound_htlcs.iter_mut() {
2256                         if let Some(fail_reason) = if let &mut OutboundHTLCState::RemoteRemoved(ref mut fail_reason) = &mut htlc.state {
2257                                 Some(fail_reason.take())
2258                         } else { None } {
2259                                 htlc.state = OutboundHTLCState::AwaitingRemoteRevokeToRemove(fail_reason);
2260                                 need_commitment = true;
2261                         }
2262                 }
2263
2264                 self.cur_holder_commitment_transaction_number -= 1;
2265                 // Note that if we need_commitment & !AwaitingRemoteRevoke we'll call
2266                 // send_commitment_no_status_check() next which will reset this to RAAFirst.
2267                 self.resend_order = RAACommitmentOrder::CommitmentFirst;
2268
2269                 if (self.channel_state & ChannelState::MonitorUpdateFailed as u32) != 0 {
2270                         // In case we initially failed monitor updating without requiring a response, we need
2271                         // to make sure the RAA gets sent first.
2272                         self.monitor_pending_revoke_and_ack = true;
2273                         if need_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 {
2274                                 // If we were going to send a commitment_signed after the RAA, go ahead and do all
2275                                 // the corresponding HTLC status updates so that get_last_commitment_update
2276                                 // includes the right HTLCs.
2277                                 self.monitor_pending_commitment_signed = true;
2278                                 let (_, mut additional_update) = self.send_commitment_no_status_check(logger).map_err(|e| (None, e))?;
2279                                 // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2280                                 // strictly increasing by one, so decrement it here.
2281                                 self.latest_monitor_update_id = monitor_update.update_id;
2282                                 monitor_update.updates.append(&mut additional_update.updates);
2283                         }
2284                         // TODO: Call maybe_propose_first_closing_signed on restoration (or call it here and
2285                         // re-send the message on restoration)
2286                         return Err((Some(monitor_update), ChannelError::Ignore("Previous monitor update failure prevented generation of RAA".to_owned())));
2287                 }
2288
2289                 let (commitment_signed, closing_signed) = if need_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 {
2290                         // If we're AwaitingRemoteRevoke we can't send a new commitment here, but that's ok -
2291                         // we'll send one right away when we get the revoke_and_ack when we
2292                         // free_holding_cell_htlcs().
2293                         let (msg, mut additional_update) = self.send_commitment_no_status_check(logger).map_err(|e| (None, e))?;
2294                         // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2295                         // strictly increasing by one, so decrement it here.
2296                         self.latest_monitor_update_id = monitor_update.update_id;
2297                         monitor_update.updates.append(&mut additional_update.updates);
2298                         (Some(msg), None)
2299                 } else if !need_commitment {
2300                         (None, self.maybe_propose_first_closing_signed(fee_estimator))
2301                 } else { (None, None) };
2302
2303                 Ok((msgs::RevokeAndACK {
2304                         channel_id: self.channel_id,
2305                         per_commitment_secret,
2306                         next_per_commitment_point,
2307                 }, commitment_signed, closing_signed, monitor_update))
2308         }
2309
2310         /// Used to fulfill holding_cell_htlcs when we get a remote ack (or implicitly get it by them
2311         /// fulfilling or failing the last pending HTLC)
2312         fn free_holding_cell_htlcs<L: Deref>(&mut self, logger: &L) -> Result<(Option<(msgs::CommitmentUpdate, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>), ChannelError> where L::Target: Logger {
2313                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, 0);
2314                 if self.holding_cell_htlc_updates.len() != 0 || self.holding_cell_update_fee.is_some() {
2315                         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 { "" });
2316
2317                         let mut monitor_update = ChannelMonitorUpdate {
2318                                 update_id: self.latest_monitor_update_id + 1, // We don't increment this yet!
2319                                 updates: Vec::new(),
2320                         };
2321
2322                         let mut htlc_updates = Vec::new();
2323                         mem::swap(&mut htlc_updates, &mut self.holding_cell_htlc_updates);
2324                         let mut update_add_htlcs = Vec::with_capacity(htlc_updates.len());
2325                         let mut update_fulfill_htlcs = Vec::with_capacity(htlc_updates.len());
2326                         let mut update_fail_htlcs = Vec::with_capacity(htlc_updates.len());
2327                         let mut htlcs_to_fail = Vec::new();
2328                         for htlc_update in htlc_updates.drain(..) {
2329                                 // Note that this *can* fail, though it should be due to rather-rare conditions on
2330                                 // fee races with adding too many outputs which push our total payments just over
2331                                 // the limit. In case it's less rare than I anticipate, we may want to revisit
2332                                 // handling this case better and maybe fulfilling some of the HTLCs while attempting
2333                                 // to rebalance channels.
2334                                 match &htlc_update {
2335                                         &HTLCUpdateAwaitingACK::AddHTLC {amount_msat, cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet, ..} => {
2336                                                 match self.send_htlc(amount_msat, *payment_hash, cltv_expiry, source.clone(), onion_routing_packet.clone()) {
2337                                                         Ok(update_add_msg_option) => update_add_htlcs.push(update_add_msg_option.unwrap()),
2338                                                         Err(e) => {
2339                                                                 match e {
2340                                                                         ChannelError::Ignore(ref msg) => {
2341                                                                                 log_info!(logger, "Failed to send HTLC with payment_hash {} due to {}", log_bytes!(payment_hash.0), msg);
2342                                                                                 // If we fail to send here, then this HTLC should
2343                                                                                 // be failed backwards. Failing to send here
2344                                                                                 // indicates that this HTLC may keep being put back
2345                                                                                 // into the holding cell without ever being
2346                                                                                 // successfully forwarded/failed/fulfilled, causing
2347                                                                                 // our counterparty to eventually close on us.
2348                                                                                 htlcs_to_fail.push((source.clone(), *payment_hash));
2349                                                                         },
2350                                                                         _ => {
2351                                                                                 panic!("Got a non-IgnoreError action trying to send holding cell HTLC");
2352                                                                         },
2353                                                                 }
2354                                                         }
2355                                                 }
2356                                         },
2357                                         &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, htlc_id, .. } => {
2358                                                 match self.get_update_fulfill_htlc(htlc_id, *payment_preimage, logger) {
2359                                                         Ok((update_fulfill_msg_option, additional_monitor_update_opt)) => {
2360                                                                 update_fulfill_htlcs.push(update_fulfill_msg_option.unwrap());
2361                                                                 if let Some(mut additional_monitor_update) = additional_monitor_update_opt {
2362                                                                         monitor_update.updates.append(&mut additional_monitor_update.updates);
2363                                                                 }
2364                                                         },
2365                                                         Err(e) => {
2366                                                                 if let ChannelError::Ignore(_) = e {}
2367                                                                 else {
2368                                                                         panic!("Got a non-IgnoreError action trying to fulfill holding cell HTLC");
2369                                                                 }
2370                                                         }
2371                                                 }
2372                                         },
2373                                         &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, ref err_packet } => {
2374                                                 match self.get_update_fail_htlc(htlc_id, err_packet.clone()) {
2375                                                         Ok(update_fail_msg_option) => update_fail_htlcs.push(update_fail_msg_option.unwrap()),
2376                                                         Err(e) => {
2377                                                                 if let ChannelError::Ignore(_) = e {}
2378                                                                 else {
2379                                                                         panic!("Got a non-IgnoreError action trying to fail holding cell HTLC");
2380                                                                 }
2381                                                         }
2382                                                 }
2383                                         },
2384                                 }
2385                         }
2386                         if update_add_htlcs.is_empty() && update_fulfill_htlcs.is_empty() && update_fail_htlcs.is_empty() && self.holding_cell_update_fee.is_none() {
2387                                 return Ok((None, htlcs_to_fail));
2388                         }
2389                         let update_fee = if let Some(feerate) = self.holding_cell_update_fee {
2390                                 self.pending_update_fee = self.holding_cell_update_fee.take();
2391                                 Some(msgs::UpdateFee {
2392                                         channel_id: self.channel_id,
2393                                         feerate_per_kw: feerate as u32,
2394                                 })
2395                         } else {
2396                                 None
2397                         };
2398
2399                         let (commitment_signed, mut additional_update) = self.send_commitment_no_status_check(logger)?;
2400                         // send_commitment_no_status_check and get_update_fulfill_htlc may bump latest_monitor_id
2401                         // but we want them to be strictly increasing by one, so reset it here.
2402                         self.latest_monitor_update_id = monitor_update.update_id;
2403                         monitor_update.updates.append(&mut additional_update.updates);
2404
2405                         Ok((Some((msgs::CommitmentUpdate {
2406                                 update_add_htlcs,
2407                                 update_fulfill_htlcs,
2408                                 update_fail_htlcs,
2409                                 update_fail_malformed_htlcs: Vec::new(),
2410                                 update_fee,
2411                                 commitment_signed,
2412                         }, monitor_update)), htlcs_to_fail))
2413                 } else {
2414                         Ok((None, Vec::new()))
2415                 }
2416         }
2417
2418         /// Handles receiving a remote's revoke_and_ack. Note that we may return a new
2419         /// commitment_signed message here in case we had pending outbound HTLCs to add which were
2420         /// waiting on this revoke_and_ack. The generation of this new commitment_signed may also fail,
2421         /// generating an appropriate error *after* the channel state has been updated based on the
2422         /// revoke_and_ack message.
2423         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>
2424                 where F::Target: FeeEstimator,
2425                                         L::Target: Logger,
2426         {
2427                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
2428                         return Err(ChannelError::Close("Got revoke/ACK message when channel was not in an operational state".to_owned()));
2429                 }
2430                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2431                         return Err(ChannelError::Close("Peer sent revoke_and_ack when we needed a channel_reestablish".to_owned()));
2432                 }
2433                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() {
2434                         return Err(ChannelError::Close("Peer sent revoke_and_ack after we'd started exchanging closing_signeds".to_owned()));
2435                 }
2436
2437                 if let Some(counterparty_prev_commitment_point) = self.counterparty_prev_commitment_point {
2438                         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 {
2439                                 return Err(ChannelError::Close("Got a revoke commitment secret which didn't correspond to their current pubkey".to_owned()));
2440                         }
2441                 }
2442
2443                 if self.channel_state & ChannelState::AwaitingRemoteRevoke as u32 == 0 {
2444                         // Our counterparty seems to have burned their coins to us (by revoking a state when we
2445                         // haven't given them a new commitment transaction to broadcast). We should probably
2446                         // take advantage of this by updating our channel monitor, sending them an error, and
2447                         // waiting for them to broadcast their latest (now-revoked claim). But, that would be a
2448                         // lot of work, and there's some chance this is all a misunderstanding anyway.
2449                         // We have to do *something*, though, since our signer may get mad at us for otherwise
2450                         // jumping a remote commitment number, so best to just force-close and move on.
2451                         return Err(ChannelError::Close("Received an unexpected revoke_and_ack".to_owned()));
2452                 }
2453
2454                 #[cfg(any(test, feature = "fuzztarget"))]
2455                 {
2456                         *self.next_local_commitment_tx_fee_info_cached.lock().unwrap() = None;
2457                         *self.next_remote_commitment_tx_fee_info_cached.lock().unwrap() = None;
2458                 }
2459
2460                 self.commitment_secrets.provide_secret(self.cur_counterparty_commitment_transaction_number + 1, msg.per_commitment_secret)
2461                         .map_err(|_| ChannelError::Close("Previous secrets did not match new one".to_owned()))?;
2462                 self.latest_monitor_update_id += 1;
2463                 let mut monitor_update = ChannelMonitorUpdate {
2464                         update_id: self.latest_monitor_update_id,
2465                         updates: vec![ChannelMonitorUpdateStep::CommitmentSecret {
2466                                 idx: self.cur_counterparty_commitment_transaction_number + 1,
2467                                 secret: msg.per_commitment_secret,
2468                         }],
2469                 };
2470
2471                 // Update state now that we've passed all the can-fail calls...
2472                 // (note that we may still fail to generate the new commitment_signed message, but that's
2473                 // OK, we step the channel here and *then* if the new generation fails we can fail the
2474                 // channel based on that, but stepping stuff here should be safe either way.
2475                 self.channel_state &= !(ChannelState::AwaitingRemoteRevoke as u32);
2476                 self.counterparty_prev_commitment_point = self.counterparty_cur_commitment_point;
2477                 self.counterparty_cur_commitment_point = Some(msg.next_per_commitment_point);
2478                 self.cur_counterparty_commitment_transaction_number -= 1;
2479
2480                 log_trace!(logger, "Updating HTLCs on receipt of RAA...");
2481                 let mut to_forward_infos = Vec::new();
2482                 let mut revoked_htlcs = Vec::new();
2483                 let mut update_fail_htlcs = Vec::new();
2484                 let mut update_fail_malformed_htlcs = Vec::new();
2485                 let mut require_commitment = false;
2486                 let mut value_to_self_msat_diff: i64 = 0;
2487
2488                 {
2489                         // Take references explicitly so that we can hold multiple references to self.
2490                         let pending_inbound_htlcs: &mut Vec<_> = &mut self.pending_inbound_htlcs;
2491                         let pending_outbound_htlcs: &mut Vec<_> = &mut self.pending_outbound_htlcs;
2492
2493                         // We really shouldnt have two passes here, but retain gives a non-mutable ref (Rust bug)
2494                         pending_inbound_htlcs.retain(|htlc| {
2495                                 if let &InboundHTLCState::LocalRemoved(ref reason) = &htlc.state {
2496                                         log_trace!(logger, " ...removing inbound LocalRemoved {}", log_bytes!(htlc.payment_hash.0));
2497                                         if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
2498                                                 value_to_self_msat_diff += htlc.amount_msat as i64;
2499                                         }
2500                                         false
2501                                 } else { true }
2502                         });
2503                         pending_outbound_htlcs.retain(|htlc| {
2504                                 if let &OutboundHTLCState::AwaitingRemovedRemoteRevoke(ref fail_reason) = &htlc.state {
2505                                         log_trace!(logger, " ...removing outbound AwaitingRemovedRemoteRevoke {}", log_bytes!(htlc.payment_hash.0));
2506                                         if let Some(reason) = fail_reason.clone() { // We really want take() here, but, again, non-mut ref :(
2507                                                 revoked_htlcs.push((htlc.source.clone(), htlc.payment_hash, reason));
2508                                         } else {
2509                                                 // They fulfilled, so we sent them money
2510                                                 value_to_self_msat_diff -= htlc.amount_msat as i64;
2511                                         }
2512                                         false
2513                                 } else { true }
2514                         });
2515                         for htlc in pending_inbound_htlcs.iter_mut() {
2516                                 let swap = if let &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_) = &htlc.state {
2517                                         log_trace!(logger, " ...promoting inbound AwaitingRemoteRevokeToAnnounce {} to Committed", log_bytes!(htlc.payment_hash.0));
2518                                         true
2519                                 } else if let &InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) = &htlc.state {
2520                                         log_trace!(logger, " ...promoting inbound AwaitingAnnouncedRemoteRevoke {} to Committed", log_bytes!(htlc.payment_hash.0));
2521                                         true
2522                                 } else { false };
2523                                 if swap {
2524                                         let mut state = InboundHTLCState::Committed;
2525                                         mem::swap(&mut state, &mut htlc.state);
2526
2527                                         if let InboundHTLCState::AwaitingRemoteRevokeToAnnounce(forward_info) = state {
2528                                                 htlc.state = InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info);
2529                                                 require_commitment = true;
2530                                         } else if let InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info) = state {
2531                                                 match forward_info {
2532                                                         PendingHTLCStatus::Fail(fail_msg) => {
2533                                                                 require_commitment = true;
2534                                                                 match fail_msg {
2535                                                                         HTLCFailureMsg::Relay(msg) => {
2536                                                                                 htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(msg.reason.clone()));
2537                                                                                 update_fail_htlcs.push(msg)
2538                                                                         },
2539                                                                         HTLCFailureMsg::Malformed(msg) => {
2540                                                                                 htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailMalformed((msg.sha256_of_onion, msg.failure_code)));
2541                                                                                 update_fail_malformed_htlcs.push(msg)
2542                                                                         },
2543                                                                 }
2544                                                         },
2545                                                         PendingHTLCStatus::Forward(forward_info) => {
2546                                                                 to_forward_infos.push((forward_info, htlc.htlc_id));
2547                                                                 htlc.state = InboundHTLCState::Committed;
2548                                                         }
2549                                                 }
2550                                         }
2551                                 }
2552                         }
2553                         for htlc in pending_outbound_htlcs.iter_mut() {
2554                                 if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
2555                                         log_trace!(logger, " ...promoting outbound LocalAnnounced {} to Committed", log_bytes!(htlc.payment_hash.0));
2556                                         htlc.state = OutboundHTLCState::Committed;
2557                                 }
2558                                 if let Some(fail_reason) = if let &mut OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref mut fail_reason) = &mut htlc.state {
2559                                         Some(fail_reason.take())
2560                                 } else { None } {
2561                                         log_trace!(logger, " ...promoting outbound AwaitingRemoteRevokeToRemove {} to AwaitingRemovedRemoteRevoke", log_bytes!(htlc.payment_hash.0));
2562                                         htlc.state = OutboundHTLCState::AwaitingRemovedRemoteRevoke(fail_reason);
2563                                         require_commitment = true;
2564                                 }
2565                         }
2566                 }
2567                 self.value_to_self_msat = (self.value_to_self_msat as i64 + value_to_self_msat_diff) as u64;
2568
2569                 if self.is_outbound() {
2570                         if let Some(feerate) = self.pending_update_fee.take() {
2571                                 self.feerate_per_kw = feerate;
2572                         }
2573                 } else {
2574                         if let Some(feerate) = self.pending_update_fee {
2575                                 // Because a node cannot send two commitment_signeds in a row without getting a
2576                                 // revoke_and_ack from us (as it would otherwise not know the per_commitment_point
2577                                 // it should use to create keys with) and because a node can't send a
2578                                 // commitment_signed without changes, checking if the feerate is equal to the
2579                                 // pending feerate update is sufficient to detect require_commitment.
2580                                 if feerate == self.feerate_per_kw {
2581                                         require_commitment = true;
2582                                         self.pending_update_fee = None;
2583                                 }
2584                         }
2585                 }
2586
2587                 if (self.channel_state & ChannelState::MonitorUpdateFailed as u32) == ChannelState::MonitorUpdateFailed as u32 {
2588                         // We can't actually generate a new commitment transaction (incl by freeing holding
2589                         // cells) while we can't update the monitor, so we just return what we have.
2590                         if require_commitment {
2591                                 self.monitor_pending_commitment_signed = true;
2592                                 // When the monitor updating is restored we'll call get_last_commitment_update(),
2593                                 // which does not update state, but we're definitely now awaiting a remote revoke
2594                                 // before we can step forward any more, so set it here.
2595                                 let (_, mut additional_update) = self.send_commitment_no_status_check(logger)?;
2596                                 // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2597                                 // strictly increasing by one, so decrement it here.
2598                                 self.latest_monitor_update_id = monitor_update.update_id;
2599                                 monitor_update.updates.append(&mut additional_update.updates);
2600                         }
2601                         self.monitor_pending_forwards.append(&mut to_forward_infos);
2602                         self.monitor_pending_failures.append(&mut revoked_htlcs);
2603                         return Ok((None, Vec::new(), Vec::new(), None, monitor_update, Vec::new()))
2604                 }
2605
2606                 match self.free_holding_cell_htlcs(logger)? {
2607                         (Some((mut commitment_update, mut additional_update)), htlcs_to_fail) => {
2608                                 commitment_update.update_fail_htlcs.reserve(update_fail_htlcs.len());
2609                                 for fail_msg in update_fail_htlcs.drain(..) {
2610                                         commitment_update.update_fail_htlcs.push(fail_msg);
2611                                 }
2612                                 commitment_update.update_fail_malformed_htlcs.reserve(update_fail_malformed_htlcs.len());
2613                                 for fail_msg in update_fail_malformed_htlcs.drain(..) {
2614                                         commitment_update.update_fail_malformed_htlcs.push(fail_msg);
2615                                 }
2616
2617                                 // free_holding_cell_htlcs may bump latest_monitor_id multiple times but we want them to be
2618                                 // strictly increasing by one, so decrement it here.
2619                                 self.latest_monitor_update_id = monitor_update.update_id;
2620                                 monitor_update.updates.append(&mut additional_update.updates);
2621
2622                                 Ok((Some(commitment_update), to_forward_infos, revoked_htlcs, None, monitor_update, htlcs_to_fail))
2623                         },
2624                         (None, htlcs_to_fail) => {
2625                                 if require_commitment {
2626                                         let (commitment_signed, mut additional_update) = self.send_commitment_no_status_check(logger)?;
2627
2628                                         // send_commitment_no_status_check may bump latest_monitor_id but we want them to be
2629                                         // strictly increasing by one, so decrement it here.
2630                                         self.latest_monitor_update_id = monitor_update.update_id;
2631                                         monitor_update.updates.append(&mut additional_update.updates);
2632
2633                                         Ok((Some(msgs::CommitmentUpdate {
2634                                                 update_add_htlcs: Vec::new(),
2635                                                 update_fulfill_htlcs: Vec::new(),
2636                                                 update_fail_htlcs,
2637                                                 update_fail_malformed_htlcs,
2638                                                 update_fee: None,
2639                                                 commitment_signed
2640                                         }), to_forward_infos, revoked_htlcs, None, monitor_update, htlcs_to_fail))
2641                                 } else {
2642                                         Ok((None, to_forward_infos, revoked_htlcs, self.maybe_propose_first_closing_signed(fee_estimator), monitor_update, htlcs_to_fail))
2643                                 }
2644                         }
2645                 }
2646
2647         }
2648
2649         /// Adds a pending update to this channel. See the doc for send_htlc for
2650         /// further details on the optionness of the return value.
2651         /// You MUST call send_commitment prior to any other calls on this Channel
2652         fn send_update_fee(&mut self, feerate_per_kw: u32) -> Option<msgs::UpdateFee> {
2653                 if !self.is_outbound() {
2654                         panic!("Cannot send fee from inbound channel");
2655                 }
2656                 if !self.is_usable() {
2657                         panic!("Cannot update fee until channel is fully established and we haven't started shutting down");
2658                 }
2659                 if !self.is_live() {
2660                         panic!("Cannot update fee while peer is disconnected/we're awaiting a monitor update (ChannelManager should have caught this)");
2661                 }
2662
2663                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
2664                         self.holding_cell_update_fee = Some(feerate_per_kw);
2665                         return None;
2666                 }
2667
2668                 debug_assert!(self.pending_update_fee.is_none());
2669                 self.pending_update_fee = Some(feerate_per_kw);
2670
2671                 Some(msgs::UpdateFee {
2672                         channel_id: self.channel_id,
2673                         feerate_per_kw,
2674                 })
2675         }
2676
2677         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 {
2678                 match self.send_update_fee(feerate_per_kw) {
2679                         Some(update_fee) => {
2680                                 let (commitment_signed, monitor_update) = self.send_commitment_no_status_check(logger)?;
2681                                 Ok(Some((update_fee, commitment_signed, monitor_update)))
2682                         },
2683                         None => Ok(None)
2684                 }
2685         }
2686
2687         /// Removes any uncommitted HTLCs, to be used on peer disconnection, including any pending
2688         /// HTLCs that we intended to add but haven't as we were waiting on a remote revoke.
2689         /// Returns the set of PendingHTLCStatuses from remote uncommitted HTLCs (which we're
2690         /// implicitly dropping) and the payment_hashes of HTLCs we tried to add but are dropping.
2691         /// No further message handling calls may be made until a channel_reestablish dance has
2692         /// completed.
2693         pub fn remove_uncommitted_htlcs_and_mark_paused<L: Deref>(&mut self, logger: &L) -> Vec<(HTLCSource, PaymentHash)> where L::Target: Logger {
2694                 let mut outbound_drops = Vec::new();
2695
2696                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
2697                 if self.channel_state < ChannelState::FundingSent as u32 {
2698                         self.channel_state = ChannelState::ShutdownComplete as u32;
2699                         return outbound_drops;
2700                 }
2701                 // Upon reconnect we have to start the closing_signed dance over, but shutdown messages
2702                 // will be retransmitted.
2703                 self.last_sent_closing_fee = None;
2704
2705                 let mut inbound_drop_count = 0;
2706                 self.pending_inbound_htlcs.retain(|htlc| {
2707                         match htlc.state {
2708                                 InboundHTLCState::RemoteAnnounced(_) => {
2709                                         // They sent us an update_add_htlc but we never got the commitment_signed.
2710                                         // We'll tell them what commitment_signed we're expecting next and they'll drop
2711                                         // this HTLC accordingly
2712                                         inbound_drop_count += 1;
2713                                         false
2714                                 },
2715                                 InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_)|InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) => {
2716                                         // We received a commitment_signed updating this HTLC and (at least hopefully)
2717                                         // sent a revoke_and_ack (which we can re-transmit) and have heard nothing
2718                                         // in response to it yet, so don't touch it.
2719                                         true
2720                                 },
2721                                 InboundHTLCState::Committed => true,
2722                                 InboundHTLCState::LocalRemoved(_) => {
2723                                         // We (hopefully) sent a commitment_signed updating this HTLC (which we can
2724                                         // re-transmit if needed) and they may have even sent a revoke_and_ack back
2725                                         // (that we missed). Keep this around for now and if they tell us they missed
2726                                         // the commitment_signed we can re-transmit the update then.
2727                                         true
2728                                 },
2729                         }
2730                 });
2731                 self.next_counterparty_htlc_id -= inbound_drop_count;
2732
2733                 for htlc in self.pending_outbound_htlcs.iter_mut() {
2734                         if let OutboundHTLCState::RemoteRemoved(_) = htlc.state {
2735                                 // They sent us an update to remove this but haven't yet sent the corresponding
2736                                 // commitment_signed, we need to move it back to Committed and they can re-send
2737                                 // the update upon reconnection.
2738                                 htlc.state = OutboundHTLCState::Committed;
2739                         }
2740                 }
2741
2742                 self.holding_cell_htlc_updates.retain(|htlc_update| {
2743                         match htlc_update {
2744                                 // Note that currently on channel reestablish we assert that there are
2745                                 // no holding cell HTLC update_adds, so if in the future we stop
2746                                 // dropping added HTLCs here and failing them backwards, then there will
2747                                 // need to be corresponding changes made in the Channel's re-establish
2748                                 // logic.
2749                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
2750                                         outbound_drops.push((source.clone(), payment_hash.clone()));
2751                                         false
2752                                 },
2753                                 &HTLCUpdateAwaitingACK::ClaimHTLC {..} | &HTLCUpdateAwaitingACK::FailHTLC {..} => true,
2754                         }
2755                 });
2756                 self.channel_state |= ChannelState::PeerDisconnected as u32;
2757                 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()));
2758                 outbound_drops
2759         }
2760
2761         /// Indicates that a ChannelMonitor update failed to be stored by the client and further
2762         /// updates are partially paused.
2763         /// This must be called immediately after the call which generated the ChannelMonitor update
2764         /// which failed. The messages which were generated from that call which generated the
2765         /// monitor update failure must *not* have been sent to the remote end, and must instead
2766         /// have been dropped. They will be regenerated when monitor_updating_restored is called.
2767         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)>) {
2768                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, 0);
2769                 self.monitor_pending_revoke_and_ack = resend_raa;
2770                 self.monitor_pending_commitment_signed = resend_commitment;
2771                 assert!(self.monitor_pending_forwards.is_empty());
2772                 mem::swap(&mut pending_forwards, &mut self.monitor_pending_forwards);
2773                 assert!(self.monitor_pending_failures.is_empty());
2774                 mem::swap(&mut pending_fails, &mut self.monitor_pending_failures);
2775                 self.channel_state |= ChannelState::MonitorUpdateFailed as u32;
2776         }
2777
2778         /// Indicates that the latest ChannelMonitor update has been committed by the client
2779         /// successfully and we should restore normal operation. Returns messages which should be sent
2780         /// to the remote side.
2781         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 {
2782                 assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, ChannelState::MonitorUpdateFailed as u32);
2783                 self.channel_state &= !(ChannelState::MonitorUpdateFailed as u32);
2784
2785                 let funding_broadcastable = if self.channel_state & (ChannelState::FundingSent as u32) != 0 && self.is_outbound() {
2786                         self.funding_transaction.take()
2787                 } else { None };
2788
2789                 // We will never broadcast the funding transaction when we're in MonitorUpdateFailed (and
2790                 // we assume the user never directly broadcasts the funding transaction and waits for us to
2791                 // do it). Thus, we can only ever hit monitor_pending_funding_locked when we're an inbound
2792                 // channel which failed to persist the monitor on funding_created, and we got the funding
2793                 // transaction confirmed before the monitor was persisted.
2794                 let funding_locked = if self.monitor_pending_funding_locked {
2795                         assert!(!self.is_outbound(), "Funding transaction broadcast by the local client before it should have - LDK didn't do it!");
2796                         self.monitor_pending_funding_locked = false;
2797                         let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
2798                         Some(msgs::FundingLocked {
2799                                 channel_id: self.channel_id(),
2800                                 next_per_commitment_point,
2801                         })
2802                 } else { None };
2803
2804                 let mut forwards = Vec::new();
2805                 mem::swap(&mut forwards, &mut self.monitor_pending_forwards);
2806                 let mut failures = Vec::new();
2807                 mem::swap(&mut failures, &mut self.monitor_pending_failures);
2808
2809                 if self.channel_state & (ChannelState::PeerDisconnected as u32) != 0 {
2810                         self.monitor_pending_revoke_and_ack = false;
2811                         self.monitor_pending_commitment_signed = false;
2812                         return (None, None, RAACommitmentOrder::RevokeAndACKFirst, forwards, failures, funding_broadcastable, funding_locked);
2813                 }
2814
2815                 let raa = if self.monitor_pending_revoke_and_ack {
2816                         Some(self.get_last_revoke_and_ack())
2817                 } else { None };
2818                 let commitment_update = if self.monitor_pending_commitment_signed {
2819                         Some(self.get_last_commitment_update(logger))
2820                 } else { None };
2821
2822                 self.monitor_pending_revoke_and_ack = false;
2823                 self.monitor_pending_commitment_signed = false;
2824                 let order = self.resend_order.clone();
2825                 log_trace!(logger, "Restored monitor updating resulting in {}{} commitment update and {} RAA, with {} first",
2826                         if funding_broadcastable.is_some() { "a funding broadcastable, " } else { "" },
2827                         if commitment_update.is_some() { "a" } else { "no" },
2828                         if raa.is_some() { "an" } else { "no" },
2829                         match order { RAACommitmentOrder::CommitmentFirst => "commitment", RAACommitmentOrder::RevokeAndACKFirst => "RAA"});
2830                 (raa, commitment_update, order, forwards, failures, funding_broadcastable, funding_locked)
2831         }
2832
2833         pub fn update_fee<F: Deref>(&mut self, fee_estimator: &F, msg: &msgs::UpdateFee) -> Result<(), ChannelError>
2834                 where F::Target: FeeEstimator
2835         {
2836                 if self.is_outbound() {
2837                         return Err(ChannelError::Close("Non-funding remote tried to update channel fee".to_owned()));
2838                 }
2839                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
2840                         return Err(ChannelError::Close("Peer sent update_fee when we needed a channel_reestablish".to_owned()));
2841                 }
2842                 Channel::<Signer>::check_remote_fee(fee_estimator, msg.feerate_per_kw)?;
2843                 self.pending_update_fee = Some(msg.feerate_per_kw);
2844                 self.update_time_counter += 1;
2845                 Ok(())
2846         }
2847
2848         fn get_last_revoke_and_ack(&self) -> msgs::RevokeAndACK {
2849                 let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
2850                 let per_commitment_secret = self.holder_signer.release_commitment_secret(self.cur_holder_commitment_transaction_number + 2);
2851                 msgs::RevokeAndACK {
2852                         channel_id: self.channel_id,
2853                         per_commitment_secret,
2854                         next_per_commitment_point,
2855                 }
2856         }
2857
2858         fn get_last_commitment_update<L: Deref>(&self, logger: &L) -> msgs::CommitmentUpdate where L::Target: Logger {
2859                 let mut update_add_htlcs = Vec::new();
2860                 let mut update_fulfill_htlcs = Vec::new();
2861                 let mut update_fail_htlcs = Vec::new();
2862                 let mut update_fail_malformed_htlcs = Vec::new();
2863
2864                 for htlc in self.pending_outbound_htlcs.iter() {
2865                         if let &OutboundHTLCState::LocalAnnounced(ref onion_packet) = &htlc.state {
2866                                 update_add_htlcs.push(msgs::UpdateAddHTLC {
2867                                         channel_id: self.channel_id(),
2868                                         htlc_id: htlc.htlc_id,
2869                                         amount_msat: htlc.amount_msat,
2870                                         payment_hash: htlc.payment_hash,
2871                                         cltv_expiry: htlc.cltv_expiry,
2872                                         onion_routing_packet: (**onion_packet).clone(),
2873                                 });
2874                         }
2875                 }
2876
2877                 for htlc in self.pending_inbound_htlcs.iter() {
2878                         if let &InboundHTLCState::LocalRemoved(ref reason) = &htlc.state {
2879                                 match reason {
2880                                         &InboundHTLCRemovalReason::FailRelay(ref err_packet) => {
2881                                                 update_fail_htlcs.push(msgs::UpdateFailHTLC {
2882                                                         channel_id: self.channel_id(),
2883                                                         htlc_id: htlc.htlc_id,
2884                                                         reason: err_packet.clone()
2885                                                 });
2886                                         },
2887                                         &InboundHTLCRemovalReason::FailMalformed((ref sha256_of_onion, ref failure_code)) => {
2888                                                 update_fail_malformed_htlcs.push(msgs::UpdateFailMalformedHTLC {
2889                                                         channel_id: self.channel_id(),
2890                                                         htlc_id: htlc.htlc_id,
2891                                                         sha256_of_onion: sha256_of_onion.clone(),
2892                                                         failure_code: failure_code.clone(),
2893                                                 });
2894                                         },
2895                                         &InboundHTLCRemovalReason::Fulfill(ref payment_preimage) => {
2896                                                 update_fulfill_htlcs.push(msgs::UpdateFulfillHTLC {
2897                                                         channel_id: self.channel_id(),
2898                                                         htlc_id: htlc.htlc_id,
2899                                                         payment_preimage: payment_preimage.clone(),
2900                                                 });
2901                                         },
2902                                 }
2903                         }
2904                 }
2905
2906                 log_trace!(logger, "Regenerated latest commitment update with {} update_adds, {} update_fulfills, {} update_fails, and {} update_fail_malformeds",
2907                                 update_add_htlcs.len(), update_fulfill_htlcs.len(), update_fail_htlcs.len(), update_fail_malformed_htlcs.len());
2908                 msgs::CommitmentUpdate {
2909                         update_add_htlcs, update_fulfill_htlcs, update_fail_htlcs, update_fail_malformed_htlcs,
2910                         update_fee: None,
2911                         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,
2912                 }
2913         }
2914
2915         /// May panic if some calls other than message-handling calls (which will all Err immediately)
2916         /// have been called between remove_uncommitted_htlcs_and_mark_paused and this call.
2917         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 {
2918                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == 0 {
2919                         // While BOLT 2 doesn't indicate explicitly we should error this channel here, it
2920                         // almost certainly indicates we are going to end up out-of-sync in some way, so we
2921                         // just close here instead of trying to recover.
2922                         return Err(ChannelError::Close("Peer sent a loose channel_reestablish not after reconnect".to_owned()));
2923                 }
2924
2925                 if msg.next_local_commitment_number >= INITIAL_COMMITMENT_NUMBER || msg.next_remote_commitment_number >= INITIAL_COMMITMENT_NUMBER ||
2926                         msg.next_local_commitment_number == 0 {
2927                         return Err(ChannelError::Close("Peer sent a garbage channel_reestablish".to_owned()));
2928                 }
2929
2930                 if msg.next_remote_commitment_number > 0 {
2931                         match msg.data_loss_protect {
2932                                 OptionalField::Present(ref data_loss) => {
2933                                         let expected_point = self.holder_signer.get_per_commitment_point(INITIAL_COMMITMENT_NUMBER - msg.next_remote_commitment_number + 1, &self.secp_ctx);
2934                                         let given_secret = SecretKey::from_slice(&data_loss.your_last_per_commitment_secret)
2935                                                 .map_err(|_| ChannelError::Close("Peer sent a garbage channel_reestablish with unparseable secret key".to_owned()))?;
2936                                         if expected_point != PublicKey::from_secret_key(&self.secp_ctx, &given_secret) {
2937                                                 return Err(ChannelError::Close("Peer sent a garbage channel_reestablish with secret key not matching the commitment height provided".to_owned()));
2938                                         }
2939                                         if msg.next_remote_commitment_number > INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number {
2940                                                 return Err(ChannelError::CloseDelayBroadcast(
2941                                                         "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()
2942                                                 ));
2943                                         }
2944                                 },
2945                                 OptionalField::Absent => {}
2946                         }
2947                 }
2948
2949                 // Go ahead and unmark PeerDisconnected as various calls we may make check for it (and all
2950                 // remaining cases either succeed or ErrorMessage-fail).
2951                 self.channel_state &= !(ChannelState::PeerDisconnected as u32);
2952
2953                 let shutdown_msg = if self.channel_state & (ChannelState::LocalShutdownSent as u32) != 0 {
2954                         Some(msgs::Shutdown {
2955                                 channel_id: self.channel_id,
2956                                 scriptpubkey: self.get_closing_scriptpubkey(),
2957                         })
2958                 } else { None };
2959
2960                 if self.channel_state & (ChannelState::FundingSent as u32) == ChannelState::FundingSent as u32 {
2961                         // If we're waiting on a monitor update, we shouldn't re-send any funding_locked's.
2962                         if self.channel_state & (ChannelState::OurFundingLocked as u32) == 0 ||
2963                                         self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
2964                                 if msg.next_remote_commitment_number != 0 {
2965                                         return Err(ChannelError::Close("Peer claimed they saw a revoke_and_ack but we haven't sent funding_locked yet".to_owned()));
2966                                 }
2967                                 // Short circuit the whole handler as there is nothing we can resend them
2968                                 return Ok((None, None, None, None, RAACommitmentOrder::CommitmentFirst, shutdown_msg));
2969                         }
2970
2971                         // We have OurFundingLocked set!
2972                         let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
2973                         return Ok((Some(msgs::FundingLocked {
2974                                 channel_id: self.channel_id(),
2975                                 next_per_commitment_point,
2976                         }), None, None, None, RAACommitmentOrder::CommitmentFirst, shutdown_msg));
2977                 }
2978
2979                 let required_revoke = if msg.next_remote_commitment_number + 1 == INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number {
2980                         // Remote isn't waiting on any RevokeAndACK from us!
2981                         // Note that if we need to repeat our FundingLocked we'll do that in the next if block.
2982                         None
2983                 } else if msg.next_remote_commitment_number + 1 == (INITIAL_COMMITMENT_NUMBER - 1) - self.cur_holder_commitment_transaction_number {
2984                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
2985                                 self.monitor_pending_revoke_and_ack = true;
2986                                 None
2987                         } else {
2988                                 Some(self.get_last_revoke_and_ack())
2989                         }
2990                 } else {
2991                         return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old local commitment transaction".to_owned()));
2992                 };
2993
2994                 // We increment cur_counterparty_commitment_transaction_number only upon receipt of
2995                 // revoke_and_ack, not on sending commitment_signed, so we add one if have
2996                 // AwaitingRemoteRevoke set, which indicates we sent a commitment_signed but haven't gotten
2997                 // the corresponding revoke_and_ack back yet.
2998                 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 };
2999
3000                 let resend_funding_locked = if msg.next_local_commitment_number == 1 && INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number == 1 {
3001                         // We should never have to worry about MonitorUpdateFailed resending FundingLocked
3002                         let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3003                         Some(msgs::FundingLocked {
3004                                 channel_id: self.channel_id(),
3005                                 next_per_commitment_point,
3006                         })
3007                 } else { None };
3008
3009                 if msg.next_local_commitment_number == next_counterparty_commitment_number {
3010                         if required_revoke.is_some() {
3011                                 log_debug!(logger, "Reconnected channel {} with only lost outbound RAA", log_bytes!(self.channel_id()));
3012                         } else {
3013                                 log_debug!(logger, "Reconnected channel {} with no loss", log_bytes!(self.channel_id()));
3014                         }
3015
3016                         if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateFailed as u32)) == 0 {
3017                                 // Note that if in the future we no longer drop holding cell update_adds on peer
3018                                 // disconnect, this logic will need to be updated.
3019                                 for htlc_update in self.holding_cell_htlc_updates.iter() {
3020                                         if let &HTLCUpdateAwaitingACK::AddHTLC { .. } = htlc_update {
3021                                                 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.");
3022                                         }
3023                                 }
3024
3025                                 // We're up-to-date and not waiting on a remote revoke (if we are our
3026                                 // channel_reestablish should result in them sending a revoke_and_ack), but we may
3027                                 // have received some updates while we were disconnected. Free the holding cell
3028                                 // now!
3029                                 match self.free_holding_cell_htlcs(logger) {
3030                                         Err(ChannelError::Close(msg)) => return Err(ChannelError::Close(msg)),
3031                                         Err(ChannelError::Ignore(_)) | Err(ChannelError::CloseDelayBroadcast(_)) => panic!("Got non-channel-failing result from free_holding_cell_htlcs"),
3032                                         Ok((Some((commitment_update, monitor_update)), htlcs_to_fail)) => {
3033                                                 // If in the future we no longer drop holding cell update_adds on peer
3034                                                 // disconnect, we may be handed some HTLCs to fail backwards here.
3035                                                 assert!(htlcs_to_fail.is_empty());
3036                                                 return Ok((resend_funding_locked, required_revoke, Some(commitment_update), Some(monitor_update), self.resend_order.clone(), shutdown_msg));
3037                                         },
3038                                         Ok((None, htlcs_to_fail)) => {
3039                                                 // If in the future we no longer drop holding cell update_adds on peer
3040                                                 // disconnect, we may be handed some HTLCs to fail backwards here.
3041                                                 assert!(htlcs_to_fail.is_empty());
3042                                                 return Ok((resend_funding_locked, required_revoke, None, None, self.resend_order.clone(), shutdown_msg));
3043                                         },
3044                                 }
3045                         } else {
3046                                 return Ok((resend_funding_locked, required_revoke, None, None, self.resend_order.clone(), shutdown_msg));
3047                         }
3048                 } else if msg.next_local_commitment_number == next_counterparty_commitment_number - 1 {
3049                         if required_revoke.is_some() {
3050                                 log_debug!(logger, "Reconnected channel {} with lost outbound RAA and lost remote commitment tx", log_bytes!(self.channel_id()));
3051                         } else {
3052                                 log_debug!(logger, "Reconnected channel {} with only lost remote commitment tx", log_bytes!(self.channel_id()));
3053                         }
3054
3055                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) != 0 {
3056                                 self.monitor_pending_commitment_signed = true;
3057                                 return Ok((resend_funding_locked, None, None, None, self.resend_order.clone(), shutdown_msg));
3058                         }
3059
3060                         return Ok((resend_funding_locked, required_revoke, Some(self.get_last_commitment_update(logger)), None, self.resend_order.clone(), shutdown_msg));
3061                 } else {
3062                         return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old remote commitment transaction".to_owned()));
3063                 }
3064         }
3065
3066         fn maybe_propose_first_closing_signed<F: Deref>(&mut self, fee_estimator: &F) -> Option<msgs::ClosingSigned>
3067                 where F::Target: FeeEstimator
3068         {
3069                 if !self.is_outbound() || !self.pending_inbound_htlcs.is_empty() || !self.pending_outbound_htlcs.is_empty() ||
3070                                 self.channel_state & (BOTH_SIDES_SHUTDOWN_MASK | ChannelState::AwaitingRemoteRevoke as u32) != BOTH_SIDES_SHUTDOWN_MASK ||
3071                                 self.last_sent_closing_fee.is_some() || self.pending_update_fee.is_some() {
3072                         return None;
3073                 }
3074
3075                 let mut proposed_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
3076                 if self.feerate_per_kw > proposed_feerate {
3077                         proposed_feerate = self.feerate_per_kw;
3078                 }
3079                 let tx_weight = self.get_closing_transaction_weight(Some(&self.get_closing_scriptpubkey()), Some(self.counterparty_shutdown_scriptpubkey.as_ref().unwrap()));
3080                 let proposed_total_fee_satoshis = proposed_feerate as u64 * tx_weight / 1000;
3081
3082                 let (closing_tx, total_fee_satoshis) = self.build_closing_transaction(proposed_total_fee_satoshis, false);
3083                 let sig = self.holder_signer
3084                         .sign_closing_transaction(&closing_tx, &self.secp_ctx)
3085                         .ok();
3086                 assert!(closing_tx.get_weight() as u64 <= tx_weight);
3087                 if sig.is_none() { return None; }
3088
3089                 self.last_sent_closing_fee = Some((proposed_feerate, total_fee_satoshis, sig.clone().unwrap()));
3090                 Some(msgs::ClosingSigned {
3091                         channel_id: self.channel_id,
3092                         fee_satoshis: total_fee_satoshis,
3093                         signature: sig.unwrap(),
3094                 })
3095         }
3096
3097         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>
3098                 where F::Target: FeeEstimator
3099         {
3100                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
3101                         return Err(ChannelError::Close("Peer sent shutdown when we needed a channel_reestablish".to_owned()));
3102                 }
3103                 if self.channel_state < ChannelState::FundingSent as u32 {
3104                         // Spec says we should fail the connection, not the channel, but that's nonsense, there
3105                         // are plenty of reasons you may want to fail a channel pre-funding, and spec says you
3106                         // can do that via error message without getting a connection fail anyway...
3107                         return Err(ChannelError::Close("Peer sent shutdown pre-funding generation".to_owned()));
3108                 }
3109                 for htlc in self.pending_inbound_htlcs.iter() {
3110                         if let InboundHTLCState::RemoteAnnounced(_) = htlc.state {
3111                                 return Err(ChannelError::Close("Got shutdown with remote pending HTLCs".to_owned()));
3112                         }
3113                 }
3114                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
3115
3116                 if is_unsupported_shutdown_script(&their_features, &msg.scriptpubkey) {
3117                         return Err(ChannelError::Close(format!("Got a nonstandard scriptpubkey ({}) from remote peer", msg.scriptpubkey.to_bytes().to_hex())));
3118                 }
3119
3120                 if self.counterparty_shutdown_scriptpubkey.is_some() {
3121                         if Some(&msg.scriptpubkey) != self.counterparty_shutdown_scriptpubkey.as_ref() {
3122                                 return Err(ChannelError::Close(format!("Got shutdown request with a scriptpubkey ({}) which did not match their previous scriptpubkey.", msg.scriptpubkey.to_bytes().to_hex())));
3123                         }
3124                 } else {
3125                         self.counterparty_shutdown_scriptpubkey = Some(msg.scriptpubkey.clone());
3126                 }
3127
3128                 // From here on out, we may not fail!
3129
3130                 self.channel_state |= ChannelState::RemoteShutdownSent as u32;
3131                 self.update_time_counter += 1;
3132
3133                 // We can't send our shutdown until we've committed all of our pending HTLCs, but the
3134                 // remote side is unlikely to accept any new HTLCs, so we go ahead and "free" any holding
3135                 // cell HTLCs and return them to fail the payment.
3136                 self.holding_cell_update_fee = None;
3137                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
3138                 self.holding_cell_htlc_updates.retain(|htlc_update| {
3139                         match htlc_update {
3140                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
3141                                         dropped_outbound_htlcs.push((source.clone(), payment_hash.clone()));
3142                                         false
3143                                 },
3144                                 _ => true
3145                         }
3146                 });
3147                 // If we have any LocalAnnounced updates we'll probably just get back a update_fail_htlc
3148                 // immediately after the commitment dance, but we can send a Shutdown cause we won't send
3149                 // any further commitment updates after we set LocalShutdownSent.
3150
3151                 let shutdown = if (self.channel_state & ChannelState::LocalShutdownSent as u32) == ChannelState::LocalShutdownSent as u32 {
3152                         None
3153                 } else {
3154                         Some(msgs::Shutdown {
3155                                 channel_id: self.channel_id,
3156                                 scriptpubkey: self.get_closing_scriptpubkey(),
3157                         })
3158                 };
3159
3160                 self.channel_state |= ChannelState::LocalShutdownSent as u32;
3161                 self.update_time_counter += 1;
3162
3163                 Ok((shutdown, self.maybe_propose_first_closing_signed(fee_estimator), dropped_outbound_htlcs))
3164         }
3165
3166         fn build_signed_closing_transaction(&self, tx: &mut Transaction, counterparty_sig: &Signature, sig: &Signature) {
3167                 if tx.input.len() != 1 { panic!("Tried to sign closing transaction that had input count != 1!"); }
3168                 if tx.input[0].witness.len() != 0 { panic!("Tried to re-sign closing transaction"); }
3169                 if tx.output.len() > 2 { panic!("Tried to sign bogus closing transaction"); }
3170
3171                 tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
3172
3173                 let funding_key = self.get_holder_pubkeys().funding_pubkey.serialize();
3174                 let counterparty_funding_key = self.counterparty_funding_pubkey().serialize();
3175                 if funding_key[..] < counterparty_funding_key[..] {
3176                         tx.input[0].witness.push(sig.serialize_der().to_vec());
3177                         tx.input[0].witness.push(counterparty_sig.serialize_der().to_vec());
3178                 } else {
3179                         tx.input[0].witness.push(counterparty_sig.serialize_der().to_vec());
3180                         tx.input[0].witness.push(sig.serialize_der().to_vec());
3181                 }
3182                 tx.input[0].witness[1].push(SigHashType::All as u8);
3183                 tx.input[0].witness[2].push(SigHashType::All as u8);
3184
3185                 tx.input[0].witness.push(self.get_funding_redeemscript().into_bytes());
3186         }
3187
3188         pub fn closing_signed<F: Deref>(&mut self, fee_estimator: &F, msg: &msgs::ClosingSigned) -> Result<(Option<msgs::ClosingSigned>, Option<Transaction>), ChannelError>
3189                 where F::Target: FeeEstimator
3190         {
3191                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != BOTH_SIDES_SHUTDOWN_MASK {
3192                         return Err(ChannelError::Close("Remote end sent us a closing_signed before both sides provided a shutdown".to_owned()));
3193                 }
3194                 if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
3195                         return Err(ChannelError::Close("Peer sent closing_signed when we needed a channel_reestablish".to_owned()));
3196                 }
3197                 if !self.pending_inbound_htlcs.is_empty() || !self.pending_outbound_htlcs.is_empty() {
3198                         return Err(ChannelError::Close("Remote end sent us a closing_signed while there were still pending HTLCs".to_owned()));
3199                 }
3200                 if msg.fee_satoshis > 21_000_000 * 1_0000_0000 { //this is required to stop potential overflow in build_closing_transaction
3201                         return Err(ChannelError::Close("Remote tried to send us a closing tx with > 21 million BTC fee".to_owned()));
3202                 }
3203
3204                 let funding_redeemscript = self.get_funding_redeemscript();
3205                 let (mut closing_tx, used_total_fee) = self.build_closing_transaction(msg.fee_satoshis, false);
3206                 if used_total_fee != msg.fee_satoshis {
3207                         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)));
3208                 }
3209                 let mut sighash = hash_to_message!(&bip143::SigHashCache::new(&closing_tx).signature_hash(0, &funding_redeemscript, self.channel_value_satoshis, SigHashType::All)[..]);
3210
3211                 match self.secp_ctx.verify(&sighash, &msg.signature, &self.get_counterparty_pubkeys().funding_pubkey) {
3212                         Ok(_) => {},
3213                         Err(_e) => {
3214                                 // The remote end may have decided to revoke their output due to inconsistent dust
3215                                 // limits, so check for that case by re-checking the signature here.
3216                                 closing_tx = self.build_closing_transaction(msg.fee_satoshis, true).0;
3217                                 sighash = hash_to_message!(&bip143::SigHashCache::new(&closing_tx).signature_hash(0, &funding_redeemscript, self.channel_value_satoshis, SigHashType::All)[..]);
3218                                 secp_check!(self.secp_ctx.verify(&sighash, &msg.signature, self.counterparty_funding_pubkey()), "Invalid closing tx signature from peer".to_owned());
3219                         },
3220                 };
3221
3222                 let closing_tx_max_weight = self.get_closing_transaction_weight(
3223                         if let Some(oup) = closing_tx.output.get(0) { Some(&oup.script_pubkey) } else { None },
3224                         if let Some(oup) = closing_tx.output.get(1) { Some(&oup.script_pubkey) } else { None });
3225                 if let Some((_, last_fee, sig)) = self.last_sent_closing_fee {
3226                         if last_fee == msg.fee_satoshis {
3227                                 self.build_signed_closing_transaction(&mut closing_tx, &msg.signature, &sig);
3228                                 assert!(closing_tx.get_weight() as u64 <= closing_tx_max_weight);
3229                                 debug_assert!(closing_tx.get_weight() as u64 >= closing_tx_max_weight - 2);
3230                                 self.channel_state = ChannelState::ShutdownComplete as u32;
3231                                 self.update_time_counter += 1;
3232                                 return Ok((None, Some(closing_tx)));
3233                         }
3234                 }
3235
3236                 macro_rules! propose_new_feerate {
3237                         ($new_feerate: expr) => {
3238                                 let tx_weight = self.get_closing_transaction_weight(Some(&self.get_closing_scriptpubkey()), Some(self.counterparty_shutdown_scriptpubkey.as_ref().unwrap()));
3239                                 let (closing_tx, used_total_fee) = self.build_closing_transaction($new_feerate as u64 * tx_weight / 1000, false);
3240                                 let sig = self.holder_signer
3241                                         .sign_closing_transaction(&closing_tx, &self.secp_ctx)
3242                                         .map_err(|_| ChannelError::Close("External signer refused to sign closing transaction".to_owned()))?;
3243                                 assert!(closing_tx.get_weight() as u64 <= tx_weight);
3244                                 self.last_sent_closing_fee = Some(($new_feerate, used_total_fee, sig.clone()));
3245                                 return Ok((Some(msgs::ClosingSigned {
3246                                         channel_id: self.channel_id,
3247                                         fee_satoshis: used_total_fee,
3248                                         signature: sig,
3249                                 }), None))
3250                         }
3251                 }
3252
3253                 let mut min_feerate = 253;
3254                 if self.is_outbound() {
3255                         let max_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
3256                         if (msg.fee_satoshis as u64) > max_feerate as u64 * closing_tx_max_weight / 1000 {
3257                                 if let Some((last_feerate, _, _)) = self.last_sent_closing_fee {
3258                                         if max_feerate <= last_feerate {
3259                                                 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)));
3260                                         }
3261                                 }
3262                                 propose_new_feerate!(max_feerate);
3263                         }
3264                 } else {
3265                         min_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
3266                 }
3267                 if (msg.fee_satoshis as u64) < min_feerate as u64 * closing_tx_max_weight / 1000 {
3268                         if let Some((last_feerate, _, _)) = self.last_sent_closing_fee {
3269                                 if min_feerate >= last_feerate {
3270                                         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)));
3271                                 }
3272                         }
3273                         propose_new_feerate!(min_feerate);
3274                 }
3275
3276                 let sig = self.holder_signer
3277                         .sign_closing_transaction(&closing_tx, &self.secp_ctx)
3278                         .map_err(|_| ChannelError::Close("External signer refused to sign closing transaction".to_owned()))?;
3279                 self.build_signed_closing_transaction(&mut closing_tx, &msg.signature, &sig);
3280                 assert!(closing_tx.get_weight() as u64 <= closing_tx_max_weight);
3281                 debug_assert!(closing_tx.get_weight() as u64 >= closing_tx_max_weight - 2);
3282
3283                 self.channel_state = ChannelState::ShutdownComplete as u32;
3284                 self.update_time_counter += 1;
3285
3286                 Ok((Some(msgs::ClosingSigned {
3287                         channel_id: self.channel_id,
3288                         fee_satoshis: msg.fee_satoshis,
3289                         signature: sig,
3290                 }), Some(closing_tx)))
3291         }
3292
3293         // Public utilities:
3294
3295         pub fn channel_id(&self) -> [u8; 32] {
3296                 self.channel_id
3297         }
3298
3299         /// Gets the "user_id" value passed into the construction of this channel. It has no special
3300         /// meaning and exists only to allow users to have a persistent identifier of a channel.
3301         pub fn get_user_id(&self) -> u64 {
3302                 self.user_id
3303         }
3304
3305         /// Guaranteed to be Some after both FundingLocked messages have been exchanged (and, thus,
3306         /// is_usable() returns true).
3307         /// Allowed in any state (including after shutdown)
3308         pub fn get_short_channel_id(&self) -> Option<u64> {
3309                 self.short_channel_id
3310         }
3311
3312         /// Returns the funding_txo we either got from our peer, or were given by
3313         /// get_outbound_funding_created.
3314         pub fn get_funding_txo(&self) -> Option<OutPoint> {
3315                 self.channel_transaction_parameters.funding_outpoint
3316         }
3317
3318         fn get_holder_selected_contest_delay(&self) -> u16 {
3319                 self.channel_transaction_parameters.holder_selected_contest_delay
3320         }
3321
3322         fn get_holder_pubkeys(&self) -> &ChannelPublicKeys {
3323                 &self.channel_transaction_parameters.holder_pubkeys
3324         }
3325
3326         fn get_counterparty_selected_contest_delay(&self) -> u16 {
3327                 self.channel_transaction_parameters.counterparty_parameters.as_ref().unwrap().selected_contest_delay
3328         }
3329
3330         fn get_counterparty_pubkeys(&self) -> &ChannelPublicKeys {
3331                 &self.channel_transaction_parameters.counterparty_parameters.as_ref().unwrap().pubkeys
3332         }
3333
3334         /// Allowed in any state (including after shutdown)
3335         pub fn get_counterparty_node_id(&self) -> PublicKey {
3336                 self.counterparty_node_id
3337         }
3338
3339         /// Allowed in any state (including after shutdown)
3340         #[cfg(test)]
3341         pub fn get_holder_htlc_minimum_msat(&self) -> u64 {
3342                 self.holder_htlc_minimum_msat
3343         }
3344
3345         /// Allowed in any state (including after shutdown)
3346         pub fn get_announced_htlc_max_msat(&self) -> u64 {
3347                 return cmp::min(
3348                         // Upper bound by capacity. We make it a bit less than full capacity to prevent attempts
3349                         // to use full capacity. This is an effort to reduce routing failures, because in many cases
3350                         // channel might have been used to route very small values (either by honest users or as DoS).
3351                         self.channel_value_satoshis * 1000 * 9 / 10,
3352
3353                         Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis)
3354                 );
3355         }
3356
3357         /// Allowed in any state (including after shutdown)
3358         pub fn get_counterparty_htlc_minimum_msat(&self) -> u64 {
3359                 self.counterparty_htlc_minimum_msat
3360         }
3361
3362         pub fn get_value_satoshis(&self) -> u64 {
3363                 self.channel_value_satoshis
3364         }
3365
3366         pub fn get_fee_proportional_millionths(&self) -> u32 {
3367                 self.config.fee_proportional_millionths
3368         }
3369
3370         pub fn get_cltv_expiry_delta(&self) -> u16 {
3371                 cmp::max(self.config.cltv_expiry_delta, MIN_CLTV_EXPIRY_DELTA)
3372         }
3373
3374         #[cfg(test)]
3375         pub fn get_feerate(&self) -> u32 {
3376                 self.feerate_per_kw
3377         }
3378
3379         pub fn get_cur_holder_commitment_transaction_number(&self) -> u64 {
3380                 self.cur_holder_commitment_transaction_number + 1
3381         }
3382
3383         pub fn get_cur_counterparty_commitment_transaction_number(&self) -> u64 {
3384                 self.cur_counterparty_commitment_transaction_number + 1 - if self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32) != 0 { 1 } else { 0 }
3385         }
3386
3387         pub fn get_revoked_counterparty_commitment_transaction_number(&self) -> u64 {
3388                 self.cur_counterparty_commitment_transaction_number + 2
3389         }
3390
3391         #[cfg(test)]
3392         pub fn get_signer(&self) -> &Signer {
3393                 &self.holder_signer
3394         }
3395
3396         #[cfg(test)]
3397         pub fn get_value_stat(&self) -> ChannelValueStat {
3398                 ChannelValueStat {
3399                         value_to_self_msat: self.value_to_self_msat,
3400                         channel_value_msat: self.channel_value_satoshis * 1000,
3401                         channel_reserve_msat: self.counterparty_selected_channel_reserve_satoshis * 1000,
3402                         pending_outbound_htlcs_amount_msat: self.pending_outbound_htlcs.iter().map(|ref h| h.amount_msat).sum::<u64>(),
3403                         pending_inbound_htlcs_amount_msat: self.pending_inbound_htlcs.iter().map(|ref h| h.amount_msat).sum::<u64>(),
3404                         holding_cell_outbound_amount_msat: {
3405                                 let mut res = 0;
3406                                 for h in self.holding_cell_htlc_updates.iter() {
3407                                         match h {
3408                                                 &HTLCUpdateAwaitingACK::AddHTLC{amount_msat, .. } => {
3409                                                         res += amount_msat;
3410                                                 }
3411                                                 _ => {}
3412                                         }
3413                                 }
3414                                 res
3415                         },
3416                         counterparty_max_htlc_value_in_flight_msat: self.counterparty_max_htlc_value_in_flight_msat,
3417                         counterparty_dust_limit_msat: self.counterparty_dust_limit_satoshis * 1000,
3418                 }
3419         }
3420
3421         /// Allowed in any state (including after shutdown)
3422         pub fn get_update_time_counter(&self) -> u32 {
3423                 self.update_time_counter
3424         }
3425
3426         pub fn get_latest_monitor_update_id(&self) -> u64 {
3427                 self.latest_monitor_update_id
3428         }
3429
3430         pub fn should_announce(&self) -> bool {
3431                 self.config.announced_channel
3432         }
3433
3434         pub fn is_outbound(&self) -> bool {
3435                 self.channel_transaction_parameters.is_outbound_from_holder
3436         }
3437
3438         /// Gets the fee we'd want to charge for adding an HTLC output to this Channel
3439         /// Allowed in any state (including after shutdown)
3440         pub fn get_holder_fee_base_msat<F: Deref>(&self, fee_estimator: &F) -> u32
3441                 where F::Target: FeeEstimator
3442         {
3443                 // For lack of a better metric, we calculate what it would cost to consolidate the new HTLC
3444                 // output value back into a transaction with the regular channel output:
3445
3446                 // the fee cost of the HTLC-Success/HTLC-Timeout transaction:
3447                 let mut res = self.feerate_per_kw as u64 * cmp::max(HTLC_TIMEOUT_TX_WEIGHT, HTLC_SUCCESS_TX_WEIGHT) / 1000;
3448
3449                 if self.is_outbound() {
3450                         // + the marginal fee increase cost to us in the commitment transaction:
3451                         res += self.feerate_per_kw as u64 * COMMITMENT_TX_WEIGHT_PER_HTLC / 1000;
3452                 }
3453
3454                 // + the marginal cost of an input which spends the HTLC-Success/HTLC-Timeout output:
3455                 res += fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal) as u64 * SPENDING_INPUT_FOR_A_OUTPUT_WEIGHT / 1000;
3456
3457                 res as u32
3458         }
3459
3460         /// Returns true if we've ever received a message from the remote end for this Channel
3461         pub fn have_received_message(&self) -> bool {
3462                 self.channel_state > (ChannelState::OurInitSent as u32)
3463         }
3464
3465         /// Returns true if this channel is fully established and not known to be closing.
3466         /// Allowed in any state (including after shutdown)
3467         pub fn is_usable(&self) -> bool {
3468                 let mask = ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK;
3469                 (self.channel_state & mask) == (ChannelState::ChannelFunded as u32)
3470         }
3471
3472         /// Returns true if this channel is currently available for use. This is a superset of
3473         /// is_usable() and considers things like the channel being temporarily disabled.
3474         /// Allowed in any state (including after shutdown)
3475         pub fn is_live(&self) -> bool {
3476                 self.is_usable() && (self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32) == 0)
3477         }
3478
3479         /// Returns true if this channel has been marked as awaiting a monitor update to move forward.
3480         /// Allowed in any state (including after shutdown)
3481         pub fn is_awaiting_monitor_update(&self) -> bool {
3482                 (self.channel_state & ChannelState::MonitorUpdateFailed as u32) != 0
3483         }
3484
3485         /// Returns true if funding_created was sent/received.
3486         pub fn is_funding_initiated(&self) -> bool {
3487                 self.channel_state >= ChannelState::FundingSent as u32
3488         }
3489
3490         /// Returns true if this channel is fully shut down. True here implies that no further actions
3491         /// may/will be taken on this channel, and thus this object should be freed. Any future changes
3492         /// will be handled appropriately by the chain monitor.
3493         pub fn is_shutdown(&self) -> bool {
3494                 if (self.channel_state & ChannelState::ShutdownComplete as u32) == ChannelState::ShutdownComplete as u32  {
3495                         assert!(self.channel_state == ChannelState::ShutdownComplete as u32);
3496                         true
3497                 } else { false }
3498         }
3499
3500         pub fn channel_update_status(&self) -> ChannelUpdateStatus {
3501                 self.channel_update_status
3502         }
3503
3504         pub fn set_channel_update_status(&mut self, status: ChannelUpdateStatus) {
3505                 self.channel_update_status = status;
3506         }
3507
3508         fn check_get_funding_locked(&mut self, height: u32) -> Option<msgs::FundingLocked> {
3509                 if self.funding_tx_confirmation_height == 0 {
3510                         return None;
3511                 }
3512
3513                 let funding_tx_confirmations = height as i64 - self.funding_tx_confirmation_height as i64 + 1;
3514                 if funding_tx_confirmations <= 0 {
3515                         self.funding_tx_confirmation_height = 0;
3516                 }
3517
3518                 if funding_tx_confirmations < self.minimum_depth as i64 {
3519                         return None;
3520                 }
3521
3522                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
3523                 let need_commitment_update = if non_shutdown_state == ChannelState::FundingSent as u32 {
3524                         self.channel_state |= ChannelState::OurFundingLocked as u32;
3525                         true
3526                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32) {
3527                         self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
3528                         self.update_time_counter += 1;
3529                         true
3530                 } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) {
3531                         // We got a reorg but not enough to trigger a force close, just ignore.
3532                         false
3533                 } else if self.channel_state < ChannelState::ChannelFunded as u32 {
3534                         panic!("Started confirming a channel in a state pre-FundingSent?: {}", self.channel_state);
3535                 } else {
3536                         // We got a reorg but not enough to trigger a force close, just ignore.
3537                         false
3538                 };
3539
3540                 if need_commitment_update {
3541                         if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) == 0 {
3542                                 let next_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3543                                 return Some(msgs::FundingLocked {
3544                                         channel_id: self.channel_id,
3545                                         next_per_commitment_point,
3546                                 });
3547                         } else {
3548                                 self.monitor_pending_funding_locked = true;
3549                         }
3550                 }
3551                 None
3552         }
3553
3554         /// When a transaction is confirmed, we check whether it is or spends the funding transaction
3555         /// In the first case, we store the confirmation height and calculating the short channel id.
3556         /// In the second, we simply return an Err indicating we need to be force-closed now.
3557         pub fn transactions_confirmed<L: Deref>(&mut self, block_hash: &BlockHash, height: u32, txdata: &TransactionData, logger: &L)
3558                         -> Result<Option<msgs::FundingLocked>, msgs::ErrorMessage> where L::Target: Logger {
3559                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
3560                 for &(index_in_block, tx) in txdata.iter() {
3561                         if let Some(funding_txo) = self.get_funding_txo() {
3562                                 // If we haven't yet sent a funding_locked, but are in FundingSent (ignoring
3563                                 // whether they've sent a funding_locked or not), check if we should send one.
3564                                 if non_shutdown_state & !(ChannelState::TheirFundingLocked as u32) == ChannelState::FundingSent as u32 {
3565                                         if tx.txid() == funding_txo.txid {
3566                                                 let txo_idx = funding_txo.index as usize;
3567                                                 if txo_idx >= tx.output.len() || tx.output[txo_idx].script_pubkey != self.get_funding_redeemscript().to_v0_p2wsh() ||
3568                                                                 tx.output[txo_idx].value != self.channel_value_satoshis {
3569                                                         if self.is_outbound() {
3570                                                                 // If we generated the funding transaction and it doesn't match what it
3571                                                                 // should, the client is really broken and we should just panic and
3572                                                                 // tell them off. That said, because hash collisions happen with high
3573                                                                 // probability in fuzztarget mode, if we're fuzzing we just close the
3574                                                                 // channel and move on.
3575                                                                 #[cfg(not(feature = "fuzztarget"))]
3576                                                                 panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
3577                                                         }
3578                                                         self.update_time_counter += 1;
3579                                                         return Err(msgs::ErrorMessage {
3580                                                                 channel_id: self.channel_id(),
3581                                                                 data: "funding tx had wrong script/value or output index".to_owned()
3582                                                         });
3583                                                 } else {
3584                                                         if self.is_outbound() {
3585                                                                 for input in tx.input.iter() {
3586                                                                         if input.witness.is_empty() {
3587                                                                                 // We generated a malleable funding transaction, implying we've
3588                                                                                 // just exposed ourselves to funds loss to our counterparty.
3589                                                                                 #[cfg(not(feature = "fuzztarget"))]
3590                                                                                 panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
3591                                                                         }
3592                                                                 }
3593                                                         }
3594                                                         self.funding_tx_confirmation_height = height;
3595                                                         self.funding_tx_confirmed_in = Some(*block_hash);
3596                                                         self.short_channel_id = match scid_from_parts(height as u64, index_in_block as u64, txo_idx as u64) {
3597                                                                 Ok(scid) => Some(scid),
3598                                                                 Err(_) => panic!("Block was bogus - either height was > 16 million, had > 16 million transactions, or had > 65k outputs"),
3599                                                         }
3600                                                 }
3601                                         }
3602                                         // If we allow 1-conf funding, we may need to check for funding_locked here and
3603                                         // send it immediately instead of waiting for a best_block_updated call (which
3604                                         // may have already happened for this block).
3605                                         if let Some(funding_locked) = self.check_get_funding_locked(height) {
3606                                                 return Ok(Some(funding_locked));
3607                                         }
3608                                 }
3609                                 for inp in tx.input.iter() {
3610                                         if inp.previous_output == funding_txo.into_bitcoin_outpoint() {
3611                                                 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()));
3612                                                 return Err(msgs::ErrorMessage {
3613                                                         channel_id: self.channel_id(),
3614                                                         data: "Commitment or closing transaction was confirmed on chain.".to_owned()
3615                                                 });
3616                                         }
3617                                 }
3618                         }
3619                 }
3620                 Ok(None)
3621         }
3622
3623         /// When a new block is connected, we check the height of the block against outbound holding
3624         /// cell HTLCs in case we need to give up on them prematurely and time them out. Everything
3625         /// else (e.g. commitment transaction broadcasts, HTLC transaction broadcasting, etc) is
3626         /// handled by the ChannelMonitor.
3627         ///
3628         /// If we return Err, the channel may have been closed, at which point the standard
3629         /// requirements apply - no calls may be made except those explicitly stated to be allowed
3630         /// post-shutdown.
3631         ///
3632         /// May return some HTLCs (and their payment_hash) which have timed out and should be failed
3633         /// back.
3634         pub fn best_block_updated(&mut self, height: u32, highest_header_time: u32) -> Result<(Option<msgs::FundingLocked>, Vec<(HTLCSource, PaymentHash)>), msgs::ErrorMessage> {
3635                 let mut timed_out_htlcs = Vec::new();
3636                 let unforwarded_htlc_cltv_limit = height + HTLC_FAIL_BACK_BUFFER;
3637                 self.holding_cell_htlc_updates.retain(|htlc_update| {
3638                         match htlc_update {
3639                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, ref cltv_expiry, .. } => {
3640                                         if *cltv_expiry <= unforwarded_htlc_cltv_limit {
3641                                                 timed_out_htlcs.push((source.clone(), payment_hash.clone()));
3642                                                 false
3643                                         } else { true }
3644                                 },
3645                                 _ => true
3646                         }
3647                 });
3648
3649                 self.update_time_counter = cmp::max(self.update_time_counter, highest_header_time);
3650
3651                 if let Some(funding_locked) = self.check_get_funding_locked(height) {
3652                         return Ok((Some(funding_locked), timed_out_htlcs));
3653                 }
3654
3655                 let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
3656                 if non_shutdown_state >= ChannelState::ChannelFunded as u32 ||
3657                    (non_shutdown_state & ChannelState::OurFundingLocked as u32) == ChannelState::OurFundingLocked as u32 {
3658                         let mut funding_tx_confirmations = height as i64 - self.funding_tx_confirmation_height as i64 + 1;
3659                         if self.funding_tx_confirmation_height == 0 {
3660                                 // Note that check_get_funding_locked may reset funding_tx_confirmation_height to
3661                                 // zero if it has been reorged out, however in either case, our state flags
3662                                 // indicate we've already sent a funding_locked
3663                                 funding_tx_confirmations = 0;
3664                         }
3665
3666                         // If we've sent funding_locked (or have both sent and received funding_locked), and
3667                         // the funding transaction's confirmation count has dipped below minimum_depth / 2,
3668                         // close the channel and hope we can get the latest state on chain (because presumably
3669                         // the funding transaction is at least still in the mempool of most nodes).
3670                         if funding_tx_confirmations < self.minimum_depth as i64 / 2 {
3671                                 return Err(msgs::ErrorMessage {
3672                                         channel_id: self.channel_id(),
3673                                         data: format!("Funding transaction was un-confirmed. Locked at {} confs, now have {} confs.", self.minimum_depth, funding_tx_confirmations),
3674                                 });
3675                         }
3676                 }
3677
3678                 Ok((None, timed_out_htlcs))
3679         }
3680
3681         /// Indicates the funding transaction is no longer confirmed in the main chain. This may
3682         /// force-close the channel, but may also indicate a harmless reorganization of a block or two
3683         /// before the channel has reached funding_locked and we can just wait for more blocks.
3684         pub fn funding_transaction_unconfirmed(&mut self) -> Result<(), msgs::ErrorMessage> {
3685                 if self.funding_tx_confirmation_height != 0 {
3686                         // We handle the funding disconnection by calling best_block_updated with a height one
3687                         // below where our funding was connected, implying a reorg back to conf_height - 1.
3688                         let reorg_height = self.funding_tx_confirmation_height - 1;
3689                         // We use the time field to bump the current time we set on channel updates if its
3690                         // larger. If we don't know that time has moved forward, we can just set it to the last
3691                         // time we saw and it will be ignored.
3692                         let best_time = self.update_time_counter;
3693                         match self.best_block_updated(reorg_height, best_time) {
3694                                 Ok((funding_locked, timed_out_htlcs)) => {
3695                                         assert!(funding_locked.is_none(), "We can't generate a funding with 0 confirmations?");
3696                                         assert!(timed_out_htlcs.is_empty(), "We can't have accepted HTLCs with a timeout before our funding confirmation?");
3697                                         Ok(())
3698                                 },
3699                                 Err(e) => Err(e)
3700                         }
3701                 } else {
3702                         // We never learned about the funding confirmation anyway, just ignore
3703                         Ok(())
3704                 }
3705         }
3706
3707         // Methods to get unprompted messages to send to the remote end (or where we already returned
3708         // something in the handler for the message that prompted this message):
3709
3710         pub fn get_open_channel(&self, chain_hash: BlockHash) -> msgs::OpenChannel {
3711                 if !self.is_outbound() {
3712                         panic!("Tried to open a channel for an inbound channel?");
3713                 }
3714                 if self.channel_state != ChannelState::OurInitSent as u32 {
3715                         panic!("Cannot generate an open_channel after we've moved forward");
3716                 }
3717
3718                 if self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
3719                         panic!("Tried to send an open_channel for a channel that has already advanced");
3720                 }
3721
3722                 let first_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3723                 let keys = self.get_holder_pubkeys();
3724
3725                 msgs::OpenChannel {
3726                         chain_hash,
3727                         temporary_channel_id: self.channel_id,
3728                         funding_satoshis: self.channel_value_satoshis,
3729                         push_msat: self.channel_value_satoshis * 1000 - self.value_to_self_msat,
3730                         dust_limit_satoshis: self.holder_dust_limit_satoshis,
3731                         max_htlc_value_in_flight_msat: Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis),
3732                         channel_reserve_satoshis: Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis),
3733                         htlc_minimum_msat: self.holder_htlc_minimum_msat,
3734                         feerate_per_kw: self.feerate_per_kw as u32,
3735                         to_self_delay: self.get_holder_selected_contest_delay(),
3736                         max_accepted_htlcs: OUR_MAX_HTLCS,
3737                         funding_pubkey: keys.funding_pubkey,
3738                         revocation_basepoint: keys.revocation_basepoint,
3739                         payment_point: keys.payment_point,
3740                         delayed_payment_basepoint: keys.delayed_payment_basepoint,
3741                         htlc_basepoint: keys.htlc_basepoint,
3742                         first_per_commitment_point,
3743                         channel_flags: if self.config.announced_channel {1} else {0},
3744                         shutdown_scriptpubkey: OptionalField::Present(if self.config.commit_upfront_shutdown_pubkey { self.get_closing_scriptpubkey() } else { Builder::new().into_script() })
3745                 }
3746         }
3747
3748         pub fn get_accept_channel(&self) -> msgs::AcceptChannel {
3749                 if self.is_outbound() {
3750                         panic!("Tried to send accept_channel for an outbound channel?");
3751                 }
3752                 if self.channel_state != (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32) {
3753                         panic!("Tried to send accept_channel after channel had moved forward");
3754                 }
3755                 if self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
3756                         panic!("Tried to send an accept_channel for a channel that has already advanced");
3757                 }
3758
3759                 let first_per_commitment_point = self.holder_signer.get_per_commitment_point(self.cur_holder_commitment_transaction_number, &self.secp_ctx);
3760                 let keys = self.get_holder_pubkeys();
3761
3762                 msgs::AcceptChannel {
3763                         temporary_channel_id: self.channel_id,
3764                         dust_limit_satoshis: self.holder_dust_limit_satoshis,
3765                         max_htlc_value_in_flight_msat: Channel::<Signer>::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis),
3766                         channel_reserve_satoshis: Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis),
3767                         htlc_minimum_msat: self.holder_htlc_minimum_msat,
3768                         minimum_depth: self.minimum_depth,
3769                         to_self_delay: self.get_holder_selected_contest_delay(),
3770                         max_accepted_htlcs: OUR_MAX_HTLCS,
3771                         funding_pubkey: keys.funding_pubkey,
3772                         revocation_basepoint: keys.revocation_basepoint,
3773                         payment_point: keys.payment_point,
3774                         delayed_payment_basepoint: keys.delayed_payment_basepoint,
3775                         htlc_basepoint: keys.htlc_basepoint,
3776                         first_per_commitment_point,
3777                         shutdown_scriptpubkey: OptionalField::Present(if self.config.commit_upfront_shutdown_pubkey { self.get_closing_scriptpubkey() } else { Builder::new().into_script() })
3778                 }
3779         }
3780
3781         /// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
3782         fn get_outbound_funding_created_signature<L: Deref>(&mut self, logger: &L) -> Result<Signature, ChannelError> where L::Target: Logger {
3783                 let counterparty_keys = self.build_remote_transaction_keys()?;
3784                 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;
3785                 Ok(self.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, &self.secp_ctx)
3786                                 .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0)
3787         }
3788
3789         /// Updates channel state with knowledge of the funding transaction's txid/index, and generates
3790         /// a funding_created message for the remote peer.
3791         /// Panics if called at some time other than immediately after initial handshake, if called twice,
3792         /// or if called on an inbound channel.
3793         /// Note that channel_id changes during this call!
3794         /// Do NOT broadcast the funding transaction until after a successful funding_signed call!
3795         /// If an Err is returned, it is a ChannelError::Close.
3796         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 {
3797                 if !self.is_outbound() {
3798                         panic!("Tried to create outbound funding_created message on an inbound channel!");
3799                 }
3800                 if self.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
3801                         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)");
3802                 }
3803                 if self.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
3804                                 self.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
3805                                 self.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
3806                         panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
3807                 }
3808
3809                 self.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
3810                 self.holder_signer.ready_channel(&self.channel_transaction_parameters);
3811
3812                 let signature = match self.get_outbound_funding_created_signature(logger) {
3813                         Ok(res) => res,
3814                         Err(e) => {
3815                                 log_error!(logger, "Got bad signatures: {:?}!", e);
3816                                 self.channel_transaction_parameters.funding_outpoint = None;
3817                                 return Err(e);
3818                         }
3819                 };
3820
3821                 let temporary_channel_id = self.channel_id;
3822
3823                 // Now that we're past error-generating stuff, update our local state:
3824
3825                 self.channel_state = ChannelState::FundingCreated as u32;
3826                 self.channel_id = funding_txo.to_channel_id();
3827                 self.funding_transaction = Some(funding_transaction);
3828
3829                 Ok(msgs::FundingCreated {
3830                         temporary_channel_id,
3831                         funding_txid: funding_txo.txid,
3832                         funding_output_index: funding_txo.index,
3833                         signature
3834                 })
3835         }
3836
3837         /// Gets an UnsignedChannelAnnouncement, as well as a signature covering it using our
3838         /// bitcoin_key, if available, for this channel. The channel must be publicly announceable and
3839         /// available for use (have exchanged FundingLocked messages in both directions). Should be used
3840         /// for both loose and in response to an AnnouncementSignatures message from the remote peer.
3841         /// Will only fail if we're not in a state where channel_announcement may be sent (including
3842         /// closing).
3843         /// Note that the "channel must be funded" requirement is stricter than BOLT 7 requires - see
3844         /// https://github.com/lightningnetwork/lightning-rfc/issues/468
3845         pub fn get_channel_announcement(&self, node_id: PublicKey, chain_hash: BlockHash) -> Result<(msgs::UnsignedChannelAnnouncement, Signature), ChannelError> {
3846                 if !self.config.announced_channel {
3847                         return Err(ChannelError::Ignore("Channel is not available for public announcements".to_owned()));
3848                 }
3849                 if self.channel_state & (ChannelState::ChannelFunded as u32) == 0 {
3850                         return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement until the channel funding has been locked".to_owned()));
3851                 }
3852                 if (self.channel_state & (ChannelState::LocalShutdownSent as u32 | ChannelState::ShutdownComplete as u32)) != 0 {
3853                         return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement once the channel is closing".to_owned()));
3854                 }
3855
3856                 let were_node_one = node_id.serialize()[..] < self.counterparty_node_id.serialize()[..];
3857
3858                 let msg = msgs::UnsignedChannelAnnouncement {
3859                         features: ChannelFeatures::known(),
3860                         chain_hash,
3861                         short_channel_id: self.get_short_channel_id().unwrap(),
3862                         node_id_1: if were_node_one { node_id } else { self.get_counterparty_node_id() },
3863                         node_id_2: if were_node_one { self.get_counterparty_node_id() } else { node_id },
3864                         bitcoin_key_1: if were_node_one { self.get_holder_pubkeys().funding_pubkey } else { self.counterparty_funding_pubkey().clone() },
3865                         bitcoin_key_2: if were_node_one { self.counterparty_funding_pubkey().clone() } else { self.get_holder_pubkeys().funding_pubkey },
3866                         excess_data: Vec::new(),
3867                 };
3868
3869                 let sig = self.holder_signer.sign_channel_announcement(&msg, &self.secp_ctx)
3870                         .map_err(|_| ChannelError::Ignore("Signer rejected channel_announcement".to_owned()))?;
3871
3872                 Ok((msg, sig))
3873         }
3874
3875         /// May panic if called on a channel that wasn't immediately-previously
3876         /// self.remove_uncommitted_htlcs_and_mark_paused()'d
3877         pub fn get_channel_reestablish<L: Deref>(&self, logger: &L) -> msgs::ChannelReestablish where L::Target: Logger {
3878                 assert_eq!(self.channel_state & ChannelState::PeerDisconnected as u32, ChannelState::PeerDisconnected as u32);
3879                 assert_ne!(self.cur_counterparty_commitment_transaction_number, INITIAL_COMMITMENT_NUMBER);
3880                 // Prior to static_remotekey, my_current_per_commitment_point was critical to claiming
3881                 // current to_remote balances. However, it no longer has any use, and thus is now simply
3882                 // set to a dummy (but valid, as required by the spec) public key.
3883                 // fuzztarget mode marks a subset of pubkeys as invalid so that we can hit "invalid pubkey"
3884                 // branches, but we unwrap it below, so we arbitrarily select a dummy pubkey which is both
3885                 // valid, and valid in fuzztarget mode's arbitrary validity criteria:
3886                 let mut pk = [2; 33]; pk[1] = 0xff;
3887                 let dummy_pubkey = PublicKey::from_slice(&pk).unwrap();
3888                 let data_loss_protect = if self.cur_counterparty_commitment_transaction_number + 1 < INITIAL_COMMITMENT_NUMBER {
3889                         let remote_last_secret = self.commitment_secrets.get_secret(self.cur_counterparty_commitment_transaction_number + 2).unwrap();
3890                         log_trace!(logger, "Enough info to generate a Data Loss Protect with per_commitment_secret {}", log_bytes!(remote_last_secret));
3891                         OptionalField::Present(DataLossProtect {
3892                                 your_last_per_commitment_secret: remote_last_secret,
3893                                 my_current_per_commitment_point: dummy_pubkey
3894                         })
3895                 } else {
3896                         log_info!(logger, "Sending a data_loss_protect with no previous remote per_commitment_secret");
3897                         OptionalField::Present(DataLossProtect {
3898                                 your_last_per_commitment_secret: [0;32],
3899                                 my_current_per_commitment_point: dummy_pubkey,
3900                         })
3901                 };
3902                 msgs::ChannelReestablish {
3903                         channel_id: self.channel_id(),
3904                         // The protocol has two different commitment number concepts - the "commitment
3905                         // transaction number", which starts from 0 and counts up, and the "revocation key
3906                         // index" which starts at INITIAL_COMMITMENT_NUMBER and counts down. We track
3907                         // commitment transaction numbers by the index which will be used to reveal the
3908                         // revocation key for that commitment transaction, which means we have to convert them
3909                         // to protocol-level commitment numbers here...
3910
3911                         // next_local_commitment_number is the next commitment_signed number we expect to
3912                         // receive (indicating if they need to resend one that we missed).
3913                         next_local_commitment_number: INITIAL_COMMITMENT_NUMBER - self.cur_holder_commitment_transaction_number,
3914                         // We have to set next_remote_commitment_number to the next revoke_and_ack we expect to
3915                         // receive, however we track it by the next commitment number for a remote transaction
3916                         // (which is one further, as they always revoke previous commitment transaction, not
3917                         // the one we send) so we have to decrement by 1. Note that if
3918                         // cur_counterparty_commitment_transaction_number is INITIAL_COMMITMENT_NUMBER we will have
3919                         // dropped this channel on disconnect as it hasn't yet reached FundingSent so we can't
3920                         // overflow here.
3921                         next_remote_commitment_number: INITIAL_COMMITMENT_NUMBER - self.cur_counterparty_commitment_transaction_number - 1,
3922                         data_loss_protect,
3923                 }
3924         }
3925
3926
3927         // Send stuff to our remote peers:
3928
3929         /// Adds a pending outbound HTLC to this channel, note that you probably want
3930         /// send_htlc_and_commit instead cause you'll want both messages at once.
3931         /// This returns an option instead of a pure UpdateAddHTLC as we may be in a state where we are
3932         /// waiting on the remote peer to send us a revoke_and_ack during which time we cannot add new
3933         /// HTLCs on the wire or we wouldn't be able to determine what they actually ACK'ed.
3934         /// You MUST call send_commitment prior to any other calls on this Channel
3935         /// If an Err is returned, it's a ChannelError::Ignore!
3936         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> {
3937                 if (self.channel_state & (ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK)) != (ChannelState::ChannelFunded as u32) {
3938                         return Err(ChannelError::Ignore("Cannot send HTLC until channel is fully established and we haven't started shutting down".to_owned()));
3939                 }
3940                 let channel_total_msat = self.channel_value_satoshis * 1000;
3941                 if amount_msat > channel_total_msat {
3942                         return Err(ChannelError::Ignore(format!("Cannot send amount {}, because it is more than the total value of the channel {}", amount_msat, channel_total_msat)));
3943                 }
3944
3945                 if amount_msat == 0 {
3946                         return Err(ChannelError::Ignore("Cannot send 0-msat HTLC".to_owned()));
3947                 }
3948
3949                 if amount_msat < self.counterparty_htlc_minimum_msat {
3950                         return Err(ChannelError::Ignore(format!("Cannot send less than their minimum HTLC value ({})", self.counterparty_htlc_minimum_msat)));
3951                 }
3952
3953                 if (self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
3954                         // Note that this should never really happen, if we're !is_live() on receipt of an
3955                         // incoming HTLC for relay will result in us rejecting the HTLC and we won't allow
3956                         // the user to send directly into a !is_live() channel. However, if we
3957                         // disconnected during the time the previous hop was doing the commitment dance we may
3958                         // end up getting here after the forwarding delay. In any case, returning an
3959                         // IgnoreError will get ChannelManager to do the right thing and fail backwards now.
3960                         return Err(ChannelError::Ignore("Cannot send an HTLC while disconnected/frozen for channel monitor update".to_owned()));
3961                 }
3962
3963                 let (outbound_htlc_count, htlc_outbound_value_msat) = self.get_outbound_pending_htlc_stats();
3964                 if outbound_htlc_count + 1 > self.counterparty_max_accepted_htlcs as u32 {
3965                         return Err(ChannelError::Ignore(format!("Cannot push more than their max accepted HTLCs ({})", self.counterparty_max_accepted_htlcs)));
3966                 }
3967                 // Check their_max_htlc_value_in_flight_msat
3968                 if htlc_outbound_value_msat + amount_msat > self.counterparty_max_htlc_value_in_flight_msat {
3969                         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)));
3970                 }
3971
3972                 if !self.is_outbound() {
3973                         // Check that we won't violate the remote channel reserve by adding this HTLC.
3974                         let counterparty_balance_msat = self.channel_value_satoshis * 1000 - self.value_to_self_msat;
3975                         let holder_selected_chan_reserve_msat = Channel::<Signer>::get_holder_selected_channel_reserve_satoshis(self.channel_value_satoshis);
3976                         let htlc_candidate = HTLCCandidate::new(amount_msat, HTLCInitiator::LocalOffered);
3977                         let counterparty_commit_tx_fee_msat = self.next_remote_commit_tx_fee_msat(htlc_candidate, None);
3978                         if counterparty_balance_msat < holder_selected_chan_reserve_msat + counterparty_commit_tx_fee_msat {
3979                                 return Err(ChannelError::Ignore("Cannot send value that would put counterparty balance under holder-announced channel reserve value".to_owned()));
3980                         }
3981                 }
3982
3983                 let pending_value_to_self_msat = self.value_to_self_msat - htlc_outbound_value_msat;
3984                 if pending_value_to_self_msat < amount_msat {
3985                         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)));
3986                 }
3987
3988                 // `2 *` and extra HTLC are for the fee spike buffer.
3989                 let commit_tx_fee_msat = if self.is_outbound() {
3990                         let htlc_candidate = HTLCCandidate::new(amount_msat, HTLCInitiator::LocalOffered);
3991                         2 * self.next_local_commit_tx_fee_msat(htlc_candidate, Some(()))
3992                 } else { 0 };
3993                 if pending_value_to_self_msat - amount_msat < commit_tx_fee_msat {
3994                         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)));
3995                 }
3996
3997                 // Check self.counterparty_selected_channel_reserve_satoshis (the amount we must keep as
3998                 // reserve for the remote to have something to claim if we misbehave)
3999                 let chan_reserve_msat = self.counterparty_selected_channel_reserve_satoshis * 1000;
4000                 if pending_value_to_self_msat - amount_msat - commit_tx_fee_msat < chan_reserve_msat {
4001                         return Err(ChannelError::Ignore(format!("Cannot send value that would put our balance under counterparty-announced channel reserve value ({})", chan_reserve_msat)));
4002                 }
4003
4004                 // Now update local state:
4005                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
4006                         self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::AddHTLC {
4007                                 amount_msat,
4008                                 payment_hash,
4009                                 cltv_expiry,
4010                                 source,
4011                                 onion_routing_packet,
4012                         });
4013                         return Ok(None);
4014                 }
4015
4016                 self.pending_outbound_htlcs.push(OutboundHTLCOutput {
4017                         htlc_id: self.next_holder_htlc_id,
4018                         amount_msat,
4019                         payment_hash: payment_hash.clone(),
4020                         cltv_expiry,
4021                         state: OutboundHTLCState::LocalAnnounced(Box::new(onion_routing_packet.clone())),
4022                         source,
4023                 });
4024
4025                 let res = msgs::UpdateAddHTLC {
4026                         channel_id: self.channel_id,
4027                         htlc_id: self.next_holder_htlc_id,
4028                         amount_msat,
4029                         payment_hash,
4030                         cltv_expiry,
4031                         onion_routing_packet,
4032                 };
4033                 self.next_holder_htlc_id += 1;
4034
4035                 Ok(Some(res))
4036         }
4037
4038         /// Creates a signed commitment transaction to send to the remote peer.
4039         /// Always returns a ChannelError::Close if an immediately-preceding (read: the
4040         /// last call to this Channel) send_htlc returned Ok(Some(_)) and there is an Err.
4041         /// May panic if called except immediately after a successful, Ok(Some(_))-returning send_htlc.
4042         pub fn send_commitment<L: Deref>(&mut self, logger: &L) -> Result<(msgs::CommitmentSigned, ChannelMonitorUpdate), ChannelError> where L::Target: Logger {
4043                 if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
4044                         panic!("Cannot create commitment tx until channel is fully established");
4045                 }
4046                 if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
4047                         panic!("Cannot create commitment tx until remote revokes their previous commitment");
4048                 }
4049                 if (self.channel_state & (ChannelState::PeerDisconnected as u32)) == (ChannelState::PeerDisconnected as u32) {
4050                         panic!("Cannot create commitment tx while disconnected, as send_htlc will have returned an Err so a send_commitment precondition has been violated");
4051                 }
4052                 if (self.channel_state & (ChannelState::MonitorUpdateFailed as u32)) == (ChannelState::MonitorUpdateFailed as u32) {
4053                         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");
4054                 }
4055                 let mut have_updates = self.pending_update_fee.is_some();
4056                 for htlc in self.pending_outbound_htlcs.iter() {
4057                         if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
4058                                 have_updates = true;
4059                         }
4060                         if have_updates { break; }
4061                 }
4062                 for htlc in self.pending_inbound_htlcs.iter() {
4063                         if let InboundHTLCState::LocalRemoved(_) = htlc.state {
4064                                 have_updates = true;
4065                         }
4066                         if have_updates { break; }
4067                 }
4068                 if !have_updates {
4069                         panic!("Cannot create commitment tx until we have some updates to send");
4070                 }
4071                 self.send_commitment_no_status_check(logger)
4072         }
4073         /// Only fails in case of bad keys
4074         fn send_commitment_no_status_check<L: Deref>(&mut self, logger: &L) -> Result<(msgs::CommitmentSigned, ChannelMonitorUpdate), ChannelError> where L::Target: Logger {
4075                 // We can upgrade the status of some HTLCs that are waiting on a commitment, even if we
4076                 // fail to generate this, we still are at least at a position where upgrading their status
4077                 // is acceptable.
4078                 for htlc in self.pending_inbound_htlcs.iter_mut() {
4079                         let new_state = if let &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(ref forward_info) = &htlc.state {
4080                                 Some(InboundHTLCState::AwaitingAnnouncedRemoteRevoke(forward_info.clone()))
4081                         } else { None };
4082                         if let Some(state) = new_state {
4083                                 htlc.state = state;
4084                         }
4085                 }
4086                 for htlc in self.pending_outbound_htlcs.iter_mut() {
4087                         if let Some(fail_reason) = if let &mut OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref mut fail_reason) = &mut htlc.state {
4088                                 Some(fail_reason.take())
4089                         } else { None } {
4090                                 htlc.state = OutboundHTLCState::AwaitingRemovedRemoteRevoke(fail_reason);
4091                         }
4092                 }
4093                 self.resend_order = RAACommitmentOrder::RevokeAndACKFirst;
4094
4095                 let (res, counterparty_commitment_txid, htlcs) = match self.send_commitment_no_state_update(logger) {
4096                         Ok((res, (counterparty_commitment_tx, mut htlcs))) => {
4097                                 // Update state now that we've passed all the can-fail calls...
4098                                 let htlcs_no_ref: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)> =
4099                                         htlcs.drain(..).map(|(htlc, htlc_source)| (htlc, htlc_source.map(|source_ref| Box::new(source_ref.clone())))).collect();
4100                                 (res, counterparty_commitment_tx, htlcs_no_ref)
4101                         },
4102                         Err(e) => return Err(e),
4103                 };
4104
4105                 self.latest_monitor_update_id += 1;
4106                 let monitor_update = ChannelMonitorUpdate {
4107                         update_id: self.latest_monitor_update_id,
4108                         updates: vec![ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo {
4109                                 commitment_txid: counterparty_commitment_txid,
4110                                 htlc_outputs: htlcs.clone(),
4111                                 commitment_number: self.cur_counterparty_commitment_transaction_number,
4112                                 their_revocation_point: self.counterparty_cur_commitment_point.unwrap()
4113                         }]
4114                 };
4115                 self.channel_state |= ChannelState::AwaitingRemoteRevoke as u32;
4116                 Ok((res, monitor_update))
4117         }
4118
4119         /// Only fails in case of bad keys. Used for channel_reestablish commitment_signed generation
4120         /// when we shouldn't change HTLC/channel state.
4121         fn send_commitment_no_state_update<L: Deref>(&self, logger: &L) -> Result<(msgs::CommitmentSigned, (Txid, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>)), ChannelError> where L::Target: Logger {
4122                 let mut feerate_per_kw = self.feerate_per_kw;
4123                 if let Some(feerate) = self.pending_update_fee {
4124                         if self.is_outbound() {
4125                                 feerate_per_kw = feerate;
4126                         }
4127                 }
4128
4129                 let counterparty_keys = self.build_remote_transaction_keys()?;
4130                 let counterparty_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, true, feerate_per_kw, logger);
4131                 let counterparty_commitment_txid = counterparty_commitment_tx.0.trust().txid();
4132                 let (signature, htlc_signatures);
4133
4134                 #[cfg(any(test, feature = "fuzztarget"))]
4135                 {
4136                         if !self.is_outbound() {
4137                                 let projected_commit_tx_info = self.next_remote_commitment_tx_fee_info_cached.lock().unwrap().take();
4138                                 *self.next_local_commitment_tx_fee_info_cached.lock().unwrap() = None;
4139                                 if let Some(info) = projected_commit_tx_info {
4140                                         let total_pending_htlcs = self.pending_inbound_htlcs.len() + self.pending_outbound_htlcs.len();
4141                                         if info.total_pending_htlcs == total_pending_htlcs
4142                                                 && info.next_holder_htlc_id == self.next_holder_htlc_id
4143                                                 && info.next_counterparty_htlc_id == self.next_counterparty_htlc_id
4144                                                 && info.feerate == self.feerate_per_kw {
4145                                                         let actual_fee = self.commit_tx_fee_msat(counterparty_commitment_tx.1);
4146                                                         assert_eq!(actual_fee, info.fee);
4147                                                 }
4148                                 }
4149                         }
4150                 }
4151
4152                 {
4153                         let mut htlcs = Vec::with_capacity(counterparty_commitment_tx.2.len());
4154                         for &(ref htlc, _) in counterparty_commitment_tx.2.iter() {
4155                                 htlcs.push(htlc);
4156                         }
4157
4158                         let res = self.holder_signer.sign_counterparty_commitment(&counterparty_commitment_tx.0, &self.secp_ctx)
4159                                 .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?;
4160                         signature = res.0;
4161                         htlc_signatures = res.1;
4162
4163                         log_trace!(logger, "Signed remote commitment tx {} (txid {}) with redeemscript {} -> {}",
4164                                 encode::serialize_hex(&counterparty_commitment_tx.0.trust().built_transaction().transaction),
4165                                 &counterparty_commitment_txid,
4166                                 encode::serialize_hex(&self.get_funding_redeemscript()),
4167                                 log_bytes!(signature.serialize_compact()[..]));
4168
4169                         for (ref htlc_sig, ref htlc) in htlc_signatures.iter().zip(htlcs) {
4170                                 log_trace!(logger, "Signed remote HTLC tx {} with redeemscript {} with pubkey {} -> {}",
4171                                         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)),
4172                                         encode::serialize_hex(&chan_utils::get_htlc_redeemscript(&htlc, &counterparty_keys)),
4173                                         log_bytes!(counterparty_keys.broadcaster_htlc_key.serialize()),
4174                                         log_bytes!(htlc_sig.serialize_compact()[..]));
4175                         }
4176                 }
4177
4178                 Ok((msgs::CommitmentSigned {
4179                         channel_id: self.channel_id,
4180                         signature,
4181                         htlc_signatures,
4182                 }, (counterparty_commitment_txid, counterparty_commitment_tx.2)))
4183         }
4184
4185         /// Adds a pending outbound HTLC to this channel, and creates a signed commitment transaction
4186         /// to send to the remote peer in one go.
4187         /// Shorthand for calling send_htlc() followed by send_commitment(), see docs on those for
4188         /// more info.
4189         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 {
4190                 match self.send_htlc(amount_msat, payment_hash, cltv_expiry, source, onion_routing_packet)? {
4191                         Some(update_add_htlc) => {
4192                                 let (commitment_signed, monitor_update) = self.send_commitment_no_status_check(logger)?;
4193                                 Ok(Some((update_add_htlc, commitment_signed, monitor_update)))
4194                         },
4195                         None => Ok(None)
4196                 }
4197         }
4198
4199         /// Get forwarding information for the counterparty.
4200         pub fn counterparty_forwarding_info(&self) -> Option<CounterpartyForwardingInfo> {
4201                 self.counterparty_forwarding_info.clone()
4202         }
4203
4204         pub fn channel_update(&mut self, msg: &msgs::ChannelUpdate) -> Result<(), ChannelError> {
4205                 let usable_channel_value_msat = (self.channel_value_satoshis - self.counterparty_selected_channel_reserve_satoshis) * 1000;
4206                 if msg.contents.htlc_minimum_msat >= usable_channel_value_msat {
4207                         return Err(ChannelError::Close("Minimum htlc value is greater than channel value".to_string()));
4208                 }
4209                 self.counterparty_forwarding_info = Some(CounterpartyForwardingInfo {
4210                         fee_base_msat: msg.contents.fee_base_msat,
4211                         fee_proportional_millionths: msg.contents.fee_proportional_millionths,
4212                         cltv_expiry_delta: msg.contents.cltv_expiry_delta
4213                 });
4214
4215                 Ok(())
4216         }
4217
4218         /// Begins the shutdown process, getting a message for the remote peer and returning all
4219         /// holding cell HTLCs for payment failure.
4220         pub fn get_shutdown(&mut self) -> Result<(msgs::Shutdown, Vec<(HTLCSource, PaymentHash)>), APIError> {
4221                 for htlc in self.pending_outbound_htlcs.iter() {
4222                         if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
4223                                 return Err(APIError::APIMisuseError{err: "Cannot begin shutdown with pending HTLCs. Process pending events first".to_owned()});
4224                         }
4225                 }
4226                 if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != 0 {
4227                         if (self.channel_state & ChannelState::LocalShutdownSent as u32) == ChannelState::LocalShutdownSent as u32 {
4228                                 return Err(APIError::APIMisuseError{err: "Shutdown already in progress".to_owned()});
4229                         }
4230                         else if (self.channel_state & ChannelState::RemoteShutdownSent as u32) == ChannelState::RemoteShutdownSent as u32 {
4231                                 return Err(APIError::ChannelUnavailable{err: "Shutdown already in progress by remote".to_owned()});
4232                         }
4233                 }
4234                 assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
4235                 if self.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32) != 0 {
4236                         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()});
4237                 }
4238
4239                 let closing_script = self.get_closing_scriptpubkey();
4240
4241                 // From here on out, we may not fail!
4242                 if self.channel_state < ChannelState::FundingSent as u32 {
4243                         self.channel_state = ChannelState::ShutdownComplete as u32;
4244                 } else {
4245                         self.channel_state |= ChannelState::LocalShutdownSent as u32;
4246                 }
4247                 self.update_time_counter += 1;
4248
4249                 // Go ahead and drop holding cell updates as we'd rather fail payments than wait to send
4250                 // our shutdown until we've committed all of the pending changes.
4251                 self.holding_cell_update_fee = None;
4252                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
4253                 self.holding_cell_htlc_updates.retain(|htlc_update| {
4254                         match htlc_update {
4255                                 &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, .. } => {
4256                                         dropped_outbound_htlcs.push((source.clone(), payment_hash.clone()));
4257                                         false
4258                                 },
4259                                 _ => true
4260                         }
4261                 });
4262
4263                 Ok((msgs::Shutdown {
4264                         channel_id: self.channel_id,
4265                         scriptpubkey: closing_script,
4266                 }, dropped_outbound_htlcs))
4267         }
4268
4269         /// Gets the latest commitment transaction and any dependent transactions for relay (forcing
4270         /// shutdown of this channel - no more calls into this Channel may be made afterwards except
4271         /// those explicitly stated to be allowed after shutdown completes, eg some simple getters).
4272         /// Also returns the list of payment_hashes for channels which we can safely fail backwards
4273         /// immediately (others we will have to allow to time out).
4274         pub fn force_shutdown(&mut self, should_broadcast: bool) -> (Option<(OutPoint, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>) {
4275                 // Note that we MUST only generate a monitor update that indicates force-closure - we're
4276                 // called during initialization prior to the chain_monitor in the encompassing ChannelManager
4277                 // being fully configured in some cases. Thus, its likely any monitor events we generate will
4278                 // be delayed in being processed! See the docs for `ChannelManagerReadArgs` for more.
4279                 assert!(self.channel_state != ChannelState::ShutdownComplete as u32);
4280
4281                 // We go ahead and "free" any holding cell HTLCs or HTLCs we haven't yet committed to and
4282                 // return them to fail the payment.
4283                 let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
4284                 for htlc_update in self.holding_cell_htlc_updates.drain(..) {
4285                         match htlc_update {
4286                                 HTLCUpdateAwaitingACK::AddHTLC { source, payment_hash, .. } => {
4287                                         dropped_outbound_htlcs.push((source, payment_hash));
4288                                 },
4289                                 _ => {}
4290                         }
4291                 }
4292                 let monitor_update = if let Some(funding_txo) = self.get_funding_txo() {
4293                         // If we haven't yet exchanged funding signatures (ie channel_state < FundingSent),
4294                         // returning a channel monitor update here would imply a channel monitor update before
4295                         // we even registered the channel monitor to begin with, which is invalid.
4296                         // Thus, if we aren't actually at a point where we could conceivably broadcast the
4297                         // funding transaction, don't return a funding txo (which prevents providing the
4298                         // monitor update to the user, even if we return one).
4299                         // See test_duplicate_chan_id and test_pre_lockin_no_chan_closed_update for more.
4300                         if self.channel_state & (ChannelState::FundingSent as u32 | ChannelState::ChannelFunded as u32 | ChannelState::ShutdownComplete as u32) != 0 {
4301                                 self.latest_monitor_update_id += 1;
4302                                 Some((funding_txo, ChannelMonitorUpdate {
4303                                         update_id: self.latest_monitor_update_id,
4304                                         updates: vec![ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast }],
4305                                 }))
4306                         } else { None }
4307                 } else { None };
4308
4309                 self.channel_state = ChannelState::ShutdownComplete as u32;
4310                 self.update_time_counter += 1;
4311                 (monitor_update, dropped_outbound_htlcs)
4312         }
4313 }
4314
4315 fn is_unsupported_shutdown_script(their_features: &InitFeatures, script: &Script) -> bool {
4316         // We restrain shutdown scripts to standards forms to avoid transactions not propagating on the p2p tx-relay network
4317
4318         // BOLT 2 says we must only send a scriptpubkey of certain standard forms,
4319         // which for a a BIP-141-compliant witness program is at max 42 bytes in length.
4320         // So don't let the remote peer feed us some super fee-heavy script.
4321         let is_script_too_long = script.len() > 42;
4322         if is_script_too_long {
4323                 return true;
4324         }
4325
4326         if their_features.supports_shutdown_anysegwit() && script.is_witness_program() && script.as_bytes()[0] != OP_PUSHBYTES_0.into_u8() {
4327                 return false;
4328         }
4329
4330         return !script.is_p2pkh() && !script.is_p2sh() && !script.is_v0_p2wpkh() && !script.is_v0_p2wsh()
4331 }
4332
4333 const SERIALIZATION_VERSION: u8 = 1;
4334 const MIN_SERIALIZATION_VERSION: u8 = 1;
4335
4336 impl Writeable for InboundHTLCRemovalReason {
4337         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
4338                 match self {
4339                         &InboundHTLCRemovalReason::FailRelay(ref error_packet) => {
4340                                 0u8.write(writer)?;
4341                                 error_packet.write(writer)?;
4342                         },
4343                         &InboundHTLCRemovalReason::FailMalformed((ref onion_hash, ref err_code)) => {
4344                                 1u8.write(writer)?;
4345                                 onion_hash.write(writer)?;
4346                                 err_code.write(writer)?;
4347                         },
4348                         &InboundHTLCRemovalReason::Fulfill(ref payment_preimage) => {
4349                                 2u8.write(writer)?;
4350                                 payment_preimage.write(writer)?;
4351                         },
4352                 }
4353                 Ok(())
4354         }
4355 }
4356
4357 impl Readable for InboundHTLCRemovalReason {
4358         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
4359                 Ok(match <u8 as Readable>::read(reader)? {
4360                         0 => InboundHTLCRemovalReason::FailRelay(Readable::read(reader)?),
4361                         1 => InboundHTLCRemovalReason::FailMalformed((Readable::read(reader)?, Readable::read(reader)?)),
4362                         2 => InboundHTLCRemovalReason::Fulfill(Readable::read(reader)?),
4363                         _ => return Err(DecodeError::InvalidValue),
4364                 })
4365         }
4366 }
4367
4368 impl Writeable for ChannelUpdateStatus {
4369         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
4370                 // We only care about writing out the current state as it was announced, ie only either
4371                 // Enabled or Disabled. In the case of DisabledStaged, we most recently announced the
4372                 // channel as enabled, so we write 0. For EnabledStaged, we similarly write a 1.
4373                 match self {
4374                         ChannelUpdateStatus::Enabled => 0u8.write(writer)?,
4375                         ChannelUpdateStatus::DisabledStaged => 0u8.write(writer)?,
4376                         ChannelUpdateStatus::EnabledStaged => 1u8.write(writer)?,
4377                         ChannelUpdateStatus::Disabled => 1u8.write(writer)?,
4378                 }
4379                 Ok(())
4380         }
4381 }
4382
4383 impl Readable for ChannelUpdateStatus {
4384         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
4385                 Ok(match <u8 as Readable>::read(reader)? {
4386                         0 => ChannelUpdateStatus::Enabled,
4387                         1 => ChannelUpdateStatus::Disabled,
4388                         _ => return Err(DecodeError::InvalidValue),
4389                 })
4390         }
4391 }
4392
4393 impl<Signer: Sign> Writeable for Channel<Signer> {
4394         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
4395                 // Note that we write out as if remove_uncommitted_htlcs_and_mark_paused had just been
4396                 // called but include holding cell updates (and obviously we don't modify self).
4397
4398                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
4399                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
4400
4401                 self.user_id.write(writer)?;
4402                 self.config.write(writer)?;
4403
4404                 self.channel_id.write(writer)?;
4405                 (self.channel_state | ChannelState::PeerDisconnected as u32).write(writer)?;
4406                 self.channel_value_satoshis.write(writer)?;
4407
4408                 self.latest_monitor_update_id.write(writer)?;
4409
4410                 let mut key_data = VecWriter(Vec::new());
4411                 self.holder_signer.write(&mut key_data)?;
4412                 assert!(key_data.0.len() < core::usize::MAX);
4413                 assert!(key_data.0.len() < core::u32::MAX as usize);
4414                 (key_data.0.len() as u32).write(writer)?;
4415                 writer.write_all(&key_data.0[..])?;
4416
4417                 self.shutdown_pubkey.write(writer)?;
4418                 self.destination_script.write(writer)?;
4419
4420                 self.cur_holder_commitment_transaction_number.write(writer)?;
4421                 self.cur_counterparty_commitment_transaction_number.write(writer)?;
4422                 self.value_to_self_msat.write(writer)?;
4423
4424                 let mut dropped_inbound_htlcs = 0;
4425                 for htlc in self.pending_inbound_htlcs.iter() {
4426                         if let InboundHTLCState::RemoteAnnounced(_) = htlc.state {
4427                                 dropped_inbound_htlcs += 1;
4428                         }
4429                 }
4430                 (self.pending_inbound_htlcs.len() as u64 - dropped_inbound_htlcs).write(writer)?;
4431                 for htlc in self.pending_inbound_htlcs.iter() {
4432                         if let &InboundHTLCState::RemoteAnnounced(_) = &htlc.state {
4433                                 continue; // Drop
4434                         }
4435                         htlc.htlc_id.write(writer)?;
4436                         htlc.amount_msat.write(writer)?;
4437                         htlc.cltv_expiry.write(writer)?;
4438                         htlc.payment_hash.write(writer)?;
4439                         match &htlc.state {
4440                                 &InboundHTLCState::RemoteAnnounced(_) => unreachable!(),
4441                                 &InboundHTLCState::AwaitingRemoteRevokeToAnnounce(ref htlc_state) => {
4442                                         1u8.write(writer)?;
4443                                         htlc_state.write(writer)?;
4444                                 },
4445                                 &InboundHTLCState::AwaitingAnnouncedRemoteRevoke(ref htlc_state) => {
4446                                         2u8.write(writer)?;
4447                                         htlc_state.write(writer)?;
4448                                 },
4449                                 &InboundHTLCState::Committed => {
4450                                         3u8.write(writer)?;
4451                                 },
4452                                 &InboundHTLCState::LocalRemoved(ref removal_reason) => {
4453                                         4u8.write(writer)?;
4454                                         removal_reason.write(writer)?;
4455                                 },
4456                         }
4457                 }
4458
4459                 (self.pending_outbound_htlcs.len() as u64).write(writer)?;
4460                 for htlc in self.pending_outbound_htlcs.iter() {
4461                         htlc.htlc_id.write(writer)?;
4462                         htlc.amount_msat.write(writer)?;
4463                         htlc.cltv_expiry.write(writer)?;
4464                         htlc.payment_hash.write(writer)?;
4465                         htlc.source.write(writer)?;
4466                         match &htlc.state {
4467                                 &OutboundHTLCState::LocalAnnounced(ref onion_packet) => {
4468                                         0u8.write(writer)?;
4469                                         onion_packet.write(writer)?;
4470                                 },
4471                                 &OutboundHTLCState::Committed => {
4472                                         1u8.write(writer)?;
4473                                 },
4474                                 &OutboundHTLCState::RemoteRemoved(ref fail_reason) => {
4475                                         2u8.write(writer)?;
4476                                         fail_reason.write(writer)?;
4477                                 },
4478                                 &OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref fail_reason) => {
4479                                         3u8.write(writer)?;
4480                                         fail_reason.write(writer)?;
4481                                 },
4482                                 &OutboundHTLCState::AwaitingRemovedRemoteRevoke(ref fail_reason) => {
4483                                         4u8.write(writer)?;
4484                                         fail_reason.write(writer)?;
4485                                 },
4486                         }
4487                 }
4488
4489                 (self.holding_cell_htlc_updates.len() as u64).write(writer)?;
4490                 for update in self.holding_cell_htlc_updates.iter() {
4491                         match update {
4492                                 &HTLCUpdateAwaitingACK::AddHTLC { ref amount_msat, ref cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet } => {
4493                                         0u8.write(writer)?;
4494                                         amount_msat.write(writer)?;
4495                                         cltv_expiry.write(writer)?;
4496                                         payment_hash.write(writer)?;
4497                                         source.write(writer)?;
4498                                         onion_routing_packet.write(writer)?;
4499                                 },
4500                                 &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, ref htlc_id } => {
4501                                         1u8.write(writer)?;
4502                                         payment_preimage.write(writer)?;
4503                                         htlc_id.write(writer)?;
4504                                 },
4505                                 &HTLCUpdateAwaitingACK::FailHTLC { ref htlc_id, ref err_packet } => {
4506                                         2u8.write(writer)?;
4507                                         htlc_id.write(writer)?;
4508                                         err_packet.write(writer)?;
4509                                 }
4510                         }
4511                 }
4512
4513                 match self.resend_order {
4514                         RAACommitmentOrder::CommitmentFirst => 0u8.write(writer)?,
4515                         RAACommitmentOrder::RevokeAndACKFirst => 1u8.write(writer)?,
4516                 }
4517
4518                 self.monitor_pending_funding_locked.write(writer)?;
4519                 self.monitor_pending_revoke_and_ack.write(writer)?;
4520                 self.monitor_pending_commitment_signed.write(writer)?;
4521
4522                 (self.monitor_pending_forwards.len() as u64).write(writer)?;
4523                 for &(ref pending_forward, ref htlc_id) in self.monitor_pending_forwards.iter() {
4524                         pending_forward.write(writer)?;
4525                         htlc_id.write(writer)?;
4526                 }
4527
4528                 (self.monitor_pending_failures.len() as u64).write(writer)?;
4529                 for &(ref htlc_source, ref payment_hash, ref fail_reason) in self.monitor_pending_failures.iter() {
4530                         htlc_source.write(writer)?;
4531                         payment_hash.write(writer)?;
4532                         fail_reason.write(writer)?;
4533                 }
4534
4535                 self.pending_update_fee.write(writer)?;
4536                 self.holding_cell_update_fee.write(writer)?;
4537
4538                 self.next_holder_htlc_id.write(writer)?;
4539                 (self.next_counterparty_htlc_id - dropped_inbound_htlcs).write(writer)?;
4540                 self.update_time_counter.write(writer)?;
4541                 self.feerate_per_kw.write(writer)?;
4542
4543                 match self.last_sent_closing_fee {
4544                         Some((feerate, fee, sig)) => {
4545                                 1u8.write(writer)?;
4546                                 feerate.write(writer)?;
4547                                 fee.write(writer)?;
4548                                 sig.write(writer)?;
4549                         },
4550                         None => 0u8.write(writer)?,
4551                 }
4552
4553                 self.funding_tx_confirmed_in.write(writer)?;
4554                 self.funding_tx_confirmation_height.write(writer)?;
4555                 self.short_channel_id.write(writer)?;
4556
4557                 self.counterparty_dust_limit_satoshis.write(writer)?;
4558                 self.holder_dust_limit_satoshis.write(writer)?;
4559                 self.counterparty_max_htlc_value_in_flight_msat.write(writer)?;
4560                 self.counterparty_selected_channel_reserve_satoshis.write(writer)?;
4561                 self.counterparty_htlc_minimum_msat.write(writer)?;
4562                 self.holder_htlc_minimum_msat.write(writer)?;
4563                 self.counterparty_max_accepted_htlcs.write(writer)?;
4564                 self.minimum_depth.write(writer)?;
4565
4566                 match &self.counterparty_forwarding_info {
4567                         Some(info) => {
4568                                 1u8.write(writer)?;
4569                                 info.fee_base_msat.write(writer)?;
4570                                 info.fee_proportional_millionths.write(writer)?;
4571                                 info.cltv_expiry_delta.write(writer)?;
4572                         },
4573                         None => 0u8.write(writer)?
4574                 }
4575
4576                 self.channel_transaction_parameters.write(writer)?;
4577                 self.funding_transaction.write(writer)?;
4578
4579                 self.counterparty_cur_commitment_point.write(writer)?;
4580                 self.counterparty_prev_commitment_point.write(writer)?;
4581                 self.counterparty_node_id.write(writer)?;
4582
4583                 self.counterparty_shutdown_scriptpubkey.write(writer)?;
4584
4585                 self.commitment_secrets.write(writer)?;
4586
4587                 self.channel_update_status.write(writer)?;
4588                 Ok(())
4589         }
4590 }
4591
4592 const MAX_ALLOC_SIZE: usize = 64*1024;
4593 impl<'a, Signer: Sign, K: Deref> ReadableArgs<&'a K> for Channel<Signer>
4594                 where K::Target: KeysInterface<Signer = Signer> {
4595         fn read<R : ::std::io::Read>(reader: &mut R, keys_source: &'a K) -> Result<Self, DecodeError> {
4596                 let _ver: u8 = Readable::read(reader)?;
4597                 let min_ver: u8 = Readable::read(reader)?;
4598                 if min_ver > SERIALIZATION_VERSION {
4599                         return Err(DecodeError::UnknownVersion);
4600                 }
4601
4602                 let user_id = Readable::read(reader)?;
4603                 let config: ChannelConfig = Readable::read(reader)?;
4604
4605                 let channel_id = Readable::read(reader)?;
4606                 let channel_state = Readable::read(reader)?;
4607                 let channel_value_satoshis = Readable::read(reader)?;
4608
4609                 let latest_monitor_update_id = Readable::read(reader)?;
4610
4611                 let keys_len: u32 = Readable::read(reader)?;
4612                 let mut keys_data = Vec::with_capacity(cmp::min(keys_len as usize, MAX_ALLOC_SIZE));
4613                 while keys_data.len() != keys_len as usize {
4614                         // Read 1KB at a time to avoid accidentally allocating 4GB on corrupted channel keys
4615                         let mut data = [0; 1024];
4616                         let read_slice = &mut data[0..cmp::min(1024, keys_len as usize - keys_data.len())];
4617                         reader.read_exact(read_slice)?;
4618                         keys_data.extend_from_slice(read_slice);
4619                 }
4620                 let holder_signer = keys_source.read_chan_signer(&keys_data)?;
4621
4622                 let shutdown_pubkey = Readable::read(reader)?;
4623                 let destination_script = Readable::read(reader)?;
4624
4625                 let cur_holder_commitment_transaction_number = Readable::read(reader)?;
4626                 let cur_counterparty_commitment_transaction_number = Readable::read(reader)?;
4627                 let value_to_self_msat = Readable::read(reader)?;
4628
4629                 let pending_inbound_htlc_count: u64 = Readable::read(reader)?;
4630                 let mut pending_inbound_htlcs = Vec::with_capacity(cmp::min(pending_inbound_htlc_count as usize, OUR_MAX_HTLCS as usize));
4631                 for _ in 0..pending_inbound_htlc_count {
4632                         pending_inbound_htlcs.push(InboundHTLCOutput {
4633                                 htlc_id: Readable::read(reader)?,
4634                                 amount_msat: Readable::read(reader)?,
4635                                 cltv_expiry: Readable::read(reader)?,
4636                                 payment_hash: Readable::read(reader)?,
4637                                 state: match <u8 as Readable>::read(reader)? {
4638                                         1 => InboundHTLCState::AwaitingRemoteRevokeToAnnounce(Readable::read(reader)?),
4639                                         2 => InboundHTLCState::AwaitingAnnouncedRemoteRevoke(Readable::read(reader)?),
4640                                         3 => InboundHTLCState::Committed,
4641                                         4 => InboundHTLCState::LocalRemoved(Readable::read(reader)?),
4642                                         _ => return Err(DecodeError::InvalidValue),
4643                                 },
4644                         });
4645                 }
4646
4647                 let pending_outbound_htlc_count: u64 = Readable::read(reader)?;
4648                 let mut pending_outbound_htlcs = Vec::with_capacity(cmp::min(pending_outbound_htlc_count as usize, OUR_MAX_HTLCS as usize));
4649                 for _ in 0..pending_outbound_htlc_count {
4650                         pending_outbound_htlcs.push(OutboundHTLCOutput {
4651                                 htlc_id: Readable::read(reader)?,
4652                                 amount_msat: Readable::read(reader)?,
4653                                 cltv_expiry: Readable::read(reader)?,
4654                                 payment_hash: Readable::read(reader)?,
4655                                 source: Readable::read(reader)?,
4656                                 state: match <u8 as Readable>::read(reader)? {
4657                                         0 => OutboundHTLCState::LocalAnnounced(Box::new(Readable::read(reader)?)),
4658                                         1 => OutboundHTLCState::Committed,
4659                                         2 => OutboundHTLCState::RemoteRemoved(Readable::read(reader)?),
4660                                         3 => OutboundHTLCState::AwaitingRemoteRevokeToRemove(Readable::read(reader)?),
4661                                         4 => OutboundHTLCState::AwaitingRemovedRemoteRevoke(Readable::read(reader)?),
4662                                         _ => return Err(DecodeError::InvalidValue),
4663                                 },
4664                         });
4665                 }
4666
4667                 let holding_cell_htlc_update_count: u64 = Readable::read(reader)?;
4668                 let mut holding_cell_htlc_updates = Vec::with_capacity(cmp::min(holding_cell_htlc_update_count as usize, OUR_MAX_HTLCS as usize*2));
4669                 for _ in 0..holding_cell_htlc_update_count {
4670                         holding_cell_htlc_updates.push(match <u8 as Readable>::read(reader)? {
4671                                 0 => HTLCUpdateAwaitingACK::AddHTLC {
4672                                         amount_msat: Readable::read(reader)?,
4673                                         cltv_expiry: Readable::read(reader)?,
4674                                         payment_hash: Readable::read(reader)?,
4675                                         source: Readable::read(reader)?,
4676                                         onion_routing_packet: Readable::read(reader)?,
4677                                 },
4678                                 1 => HTLCUpdateAwaitingACK::ClaimHTLC {
4679                                         payment_preimage: Readable::read(reader)?,
4680                                         htlc_id: Readable::read(reader)?,
4681                                 },
4682                                 2 => HTLCUpdateAwaitingACK::FailHTLC {
4683                                         htlc_id: Readable::read(reader)?,
4684                                         err_packet: Readable::read(reader)?,
4685                                 },
4686                                 _ => return Err(DecodeError::InvalidValue),
4687                         });
4688                 }
4689
4690                 let resend_order = match <u8 as Readable>::read(reader)? {
4691                         0 => RAACommitmentOrder::CommitmentFirst,
4692                         1 => RAACommitmentOrder::RevokeAndACKFirst,
4693                         _ => return Err(DecodeError::InvalidValue),
4694                 };
4695
4696                 let monitor_pending_funding_locked = Readable::read(reader)?;
4697                 let monitor_pending_revoke_and_ack = Readable::read(reader)?;
4698                 let monitor_pending_commitment_signed = Readable::read(reader)?;
4699
4700                 let monitor_pending_forwards_count: u64 = Readable::read(reader)?;
4701                 let mut monitor_pending_forwards = Vec::with_capacity(cmp::min(monitor_pending_forwards_count as usize, OUR_MAX_HTLCS as usize));
4702                 for _ in 0..monitor_pending_forwards_count {
4703                         monitor_pending_forwards.push((Readable::read(reader)?, Readable::read(reader)?));
4704                 }
4705
4706                 let monitor_pending_failures_count: u64 = Readable::read(reader)?;
4707                 let mut monitor_pending_failures = Vec::with_capacity(cmp::min(monitor_pending_failures_count as usize, OUR_MAX_HTLCS as usize));
4708                 for _ in 0..monitor_pending_failures_count {
4709                         monitor_pending_failures.push((Readable::read(reader)?, Readable::read(reader)?, Readable::read(reader)?));
4710                 }
4711
4712                 let pending_update_fee = Readable::read(reader)?;
4713                 let holding_cell_update_fee = Readable::read(reader)?;
4714
4715                 let next_holder_htlc_id = Readable::read(reader)?;
4716                 let next_counterparty_htlc_id = Readable::read(reader)?;
4717                 let update_time_counter = Readable::read(reader)?;
4718                 let feerate_per_kw = Readable::read(reader)?;
4719
4720                 let last_sent_closing_fee = match <u8 as Readable>::read(reader)? {
4721                         0 => None,
4722                         1 => Some((Readable::read(reader)?, Readable::read(reader)?, Readable::read(reader)?)),
4723                         _ => return Err(DecodeError::InvalidValue),
4724                 };
4725
4726                 let funding_tx_confirmed_in = Readable::read(reader)?;
4727                 let funding_tx_confirmation_height = Readable::read(reader)?;
4728                 let short_channel_id = Readable::read(reader)?;
4729
4730                 let counterparty_dust_limit_satoshis = Readable::read(reader)?;
4731                 let holder_dust_limit_satoshis = Readable::read(reader)?;
4732                 let counterparty_max_htlc_value_in_flight_msat = Readable::read(reader)?;
4733                 let counterparty_selected_channel_reserve_satoshis = Readable::read(reader)?;
4734                 let counterparty_htlc_minimum_msat = Readable::read(reader)?;
4735                 let holder_htlc_minimum_msat = Readable::read(reader)?;
4736                 let counterparty_max_accepted_htlcs = Readable::read(reader)?;
4737                 let minimum_depth = Readable::read(reader)?;
4738
4739                 let counterparty_forwarding_info = match <u8 as Readable>::read(reader)? {
4740                         0 => None,
4741                         1 => Some(CounterpartyForwardingInfo {
4742                                 fee_base_msat: Readable::read(reader)?,
4743                                 fee_proportional_millionths: Readable::read(reader)?,
4744                                 cltv_expiry_delta: Readable::read(reader)?,
4745                         }),
4746                         _ => return Err(DecodeError::InvalidValue),
4747                 };
4748
4749                 let channel_parameters = Readable::read(reader)?;
4750                 let funding_transaction = Readable::read(reader)?;
4751
4752                 let counterparty_cur_commitment_point = Readable::read(reader)?;
4753
4754                 let counterparty_prev_commitment_point = Readable::read(reader)?;
4755                 let counterparty_node_id = Readable::read(reader)?;
4756
4757                 let counterparty_shutdown_scriptpubkey = Readable::read(reader)?;
4758                 let commitment_secrets = Readable::read(reader)?;
4759
4760                 let channel_update_status = Readable::read(reader)?;
4761
4762                 let mut secp_ctx = Secp256k1::new();
4763                 secp_ctx.seeded_randomize(&keys_source.get_secure_random_bytes());
4764
4765                 Ok(Channel {
4766                         user_id,
4767
4768                         config,
4769                         channel_id,
4770                         channel_state,
4771                         secp_ctx,
4772                         channel_value_satoshis,
4773
4774                         latest_monitor_update_id,
4775
4776                         holder_signer,
4777                         shutdown_pubkey,
4778                         destination_script,
4779
4780                         cur_holder_commitment_transaction_number,
4781                         cur_counterparty_commitment_transaction_number,
4782                         value_to_self_msat,
4783
4784                         pending_inbound_htlcs,
4785                         pending_outbound_htlcs,
4786                         holding_cell_htlc_updates,
4787
4788                         resend_order,
4789
4790                         monitor_pending_funding_locked,
4791                         monitor_pending_revoke_and_ack,
4792                         monitor_pending_commitment_signed,
4793                         monitor_pending_forwards,
4794                         monitor_pending_failures,
4795
4796                         pending_update_fee,
4797                         holding_cell_update_fee,
4798                         next_holder_htlc_id,
4799                         next_counterparty_htlc_id,
4800                         update_time_counter,
4801                         feerate_per_kw,
4802
4803                         #[cfg(debug_assertions)]
4804                         holder_max_commitment_tx_output: ::std::sync::Mutex::new((0, 0)),
4805                         #[cfg(debug_assertions)]
4806                         counterparty_max_commitment_tx_output: ::std::sync::Mutex::new((0, 0)),
4807
4808                         last_sent_closing_fee,
4809
4810                         funding_tx_confirmed_in,
4811                         funding_tx_confirmation_height,
4812                         short_channel_id,
4813
4814                         counterparty_dust_limit_satoshis,
4815                         holder_dust_limit_satoshis,
4816                         counterparty_max_htlc_value_in_flight_msat,
4817                         counterparty_selected_channel_reserve_satoshis,
4818                         counterparty_htlc_minimum_msat,
4819                         holder_htlc_minimum_msat,
4820                         counterparty_max_accepted_htlcs,
4821                         minimum_depth,
4822
4823                         counterparty_forwarding_info,
4824
4825                         channel_transaction_parameters: channel_parameters,
4826                         funding_transaction,
4827
4828                         counterparty_cur_commitment_point,
4829                         counterparty_prev_commitment_point,
4830                         counterparty_node_id,
4831
4832                         counterparty_shutdown_scriptpubkey,
4833
4834                         commitment_secrets,
4835
4836                         channel_update_status,
4837
4838                         #[cfg(any(test, feature = "fuzztarget"))]
4839                         next_local_commitment_tx_fee_info_cached: Mutex::new(None),
4840                         #[cfg(any(test, feature = "fuzztarget"))]
4841                         next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
4842                 })
4843         }
4844 }
4845
4846 #[cfg(test)]
4847 mod tests {
4848         use bitcoin::util::bip143;
4849         use bitcoin::consensus::encode::serialize;
4850         use bitcoin::blockdata::script::{Script, Builder};
4851         use bitcoin::blockdata::transaction::{Transaction, TxOut, SigHashType};
4852         use bitcoin::blockdata::constants::genesis_block;
4853         use bitcoin::blockdata::opcodes;
4854         use bitcoin::network::constants::Network;
4855         use bitcoin::hashes::hex::FromHex;
4856         use hex;
4857         use ln::{PaymentPreimage, PaymentHash};
4858         use ln::channelmanager::{BestBlock, HTLCSource};
4859         use ln::channel::{Channel,InboundHTLCOutput,OutboundHTLCOutput,InboundHTLCState,OutboundHTLCState,HTLCOutputInCommitment,HTLCCandidate,HTLCInitiator,TxCreationKeys};
4860         use ln::channel::MAX_FUNDING_SATOSHIS;
4861         use ln::features::InitFeatures;
4862         use ln::msgs::{ChannelUpdate, DataLossProtect, DecodeError, OptionalField, UnsignedChannelUpdate};
4863         use ln::chan_utils;
4864         use ln::chan_utils::{ChannelPublicKeys, HolderCommitmentTransaction, CounterpartyChannelTransactionParameters, HTLC_SUCCESS_TX_WEIGHT, HTLC_TIMEOUT_TX_WEIGHT};
4865         use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
4866         use chain::keysinterface::{InMemorySigner, KeysInterface, BaseSign};
4867         use chain::transaction::OutPoint;
4868         use util::config::UserConfig;
4869         use util::enforcing_trait_impls::EnforcingSigner;
4870         use util::test_utils;
4871         use util::logger::Logger;
4872         use bitcoin::secp256k1::{Secp256k1, Message, Signature, All};
4873         use bitcoin::secp256k1::ffi::Signature as FFISignature;
4874         use bitcoin::secp256k1::key::{SecretKey,PublicKey};
4875         use bitcoin::secp256k1::recovery::RecoverableSignature;
4876         use bitcoin::hashes::sha256::Hash as Sha256;
4877         use bitcoin::hashes::Hash;
4878         use bitcoin::hash_types::{Txid, WPubkeyHash};
4879         use std::sync::Arc;
4880
4881         struct TestFeeEstimator {
4882                 fee_est: u32
4883         }
4884         impl FeeEstimator for TestFeeEstimator {
4885                 fn get_est_sat_per_1000_weight(&self, _: ConfirmationTarget) -> u32 {
4886                         self.fee_est
4887                 }
4888         }
4889
4890         #[test]
4891         fn test_max_funding_satoshis() {
4892                 assert!(MAX_FUNDING_SATOSHIS <= 21_000_000 * 100_000_000,
4893                         "MAX_FUNDING_SATOSHIS is greater than all satoshis in existence");
4894         }
4895
4896         struct Keys {
4897                 signer: InMemorySigner,
4898         }
4899         impl KeysInterface for Keys {
4900                 type Signer = InMemorySigner;
4901
4902                 fn get_node_secret(&self) -> SecretKey { panic!(); }
4903                 fn get_destination_script(&self) -> Script {
4904                         let secp_ctx = Secp256k1::signing_only();
4905                         let channel_monitor_claim_key = SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap();
4906                         let channel_monitor_claim_key_hash = WPubkeyHash::hash(&PublicKey::from_secret_key(&secp_ctx, &channel_monitor_claim_key).serialize());
4907                         Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&channel_monitor_claim_key_hash[..]).into_script()
4908                 }
4909
4910                 fn get_shutdown_pubkey(&self) -> PublicKey {
4911                         let secp_ctx = Secp256k1::signing_only();
4912                         let channel_close_key = SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap();
4913                         PublicKey::from_secret_key(&secp_ctx, &channel_close_key)
4914                 }
4915
4916                 fn get_channel_signer(&self, _inbound: bool, _channel_value_satoshis: u64) -> InMemorySigner {
4917                         self.signer.clone()
4918                 }
4919                 fn get_secure_random_bytes(&self) -> [u8; 32] { [0; 32] }
4920                 fn read_chan_signer(&self, _data: &[u8]) -> Result<Self::Signer, DecodeError> { panic!(); }
4921                 fn sign_invoice(&self, _invoice_preimage: Vec<u8>) -> Result<RecoverableSignature, ()> { panic!(); }
4922         }
4923
4924         fn public_from_secret_hex(secp_ctx: &Secp256k1<All>, hex: &str) -> PublicKey {
4925                 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode(hex).unwrap()[..]).unwrap())
4926         }
4927
4928         // Check that, during channel creation, we use the same feerate in the open channel message
4929         // as we do in the Channel object creation itself.
4930         #[test]
4931         fn test_open_channel_msg_fee() {
4932                 let original_fee = 253;
4933                 let mut fee_est = TestFeeEstimator{fee_est: original_fee };
4934                 let secp_ctx = Secp256k1::new();
4935                 let seed = [42; 32];
4936                 let network = Network::Testnet;
4937                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
4938
4939                 let node_a_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
4940                 let config = UserConfig::default();
4941                 let node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&fee_est, &&keys_provider, node_a_node_id, 10000000, 100000, 42, &config).unwrap();
4942
4943                 // Now change the fee so we can check that the fee in the open_channel message is the
4944                 // same as the old fee.
4945                 fee_est.fee_est = 500;
4946                 let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.block_hash());
4947                 assert_eq!(open_channel_msg.feerate_per_kw, original_fee);
4948         }
4949
4950         #[test]
4951         fn test_holder_vs_counterparty_dust_limit() {
4952                 // Test that when calculating the local and remote commitment transaction fees, the correct
4953                 // dust limits are used.
4954                 let feeest = TestFeeEstimator{fee_est: 15000};
4955                 let secp_ctx = Secp256k1::new();
4956                 let seed = [42; 32];
4957                 let network = Network::Testnet;
4958                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
4959
4960                 // Go through the flow of opening a channel between two nodes, making sure
4961                 // they have different dust limits.
4962
4963                 // Create Node A's channel pointing to Node B's pubkey
4964                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
4965                 let config = UserConfig::default();
4966                 let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, 10000000, 100000, 42, &config).unwrap();
4967
4968                 // Create Node B's channel by receiving Node A's open_channel message
4969                 // Make sure A's dust limit is as we expect.
4970                 let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.block_hash());
4971                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
4972                 let node_b_chan = Channel::<EnforcingSigner>::new_from_req(&&feeest, &&keys_provider, node_b_node_id, InitFeatures::known(), &open_channel_msg, 7, &config).unwrap();
4973
4974                 // Node B --> Node A: accept channel, explicitly setting B's dust limit.
4975                 let mut accept_channel_msg = node_b_chan.get_accept_channel();
4976                 accept_channel_msg.dust_limit_satoshis = 546;
4977                 node_a_chan.accept_channel(&accept_channel_msg, &config, InitFeatures::known()).unwrap();
4978                 node_a_chan.holder_dust_limit_satoshis = 1560;
4979
4980                 // Put some inbound and outbound HTLCs in A's channel.
4981                 let htlc_amount_msat = 11_092_000; // put an amount below A's effective dust limit but above B's.
4982                 node_a_chan.pending_inbound_htlcs.push(InboundHTLCOutput {
4983                         htlc_id: 0,
4984                         amount_msat: htlc_amount_msat,
4985                         payment_hash: PaymentHash(Sha256::hash(&[42; 32]).into_inner()),
4986                         cltv_expiry: 300000000,
4987                         state: InboundHTLCState::Committed,
4988                 });
4989
4990                 node_a_chan.pending_outbound_htlcs.push(OutboundHTLCOutput {
4991                         htlc_id: 1,
4992                         amount_msat: htlc_amount_msat, // put an amount below A's dust amount but above B's.
4993                         payment_hash: PaymentHash(Sha256::hash(&[43; 32]).into_inner()),
4994                         cltv_expiry: 200000000,
4995                         state: OutboundHTLCState::Committed,
4996                         source: HTLCSource::OutboundRoute {
4997                                 path: Vec::new(),
4998                                 session_priv: SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(),
4999                                 first_hop_htlc_msat: 548,
5000                         }
5001                 });
5002
5003                 // Make sure when Node A calculates their local commitment transaction, none of the HTLCs pass
5004                 // the dust limit check.
5005                 let htlc_candidate = HTLCCandidate::new(htlc_amount_msat, HTLCInitiator::LocalOffered);
5006                 let local_commit_tx_fee = node_a_chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
5007                 let local_commit_fee_0_htlcs = node_a_chan.commit_tx_fee_msat(0);
5008                 assert_eq!(local_commit_tx_fee, local_commit_fee_0_htlcs);
5009
5010                 // Finally, make sure that when Node A calculates the remote's commitment transaction fees, all
5011                 // of the HTLCs are seen to be above the dust limit.
5012                 node_a_chan.channel_transaction_parameters.is_outbound_from_holder = false;
5013                 let remote_commit_fee_3_htlcs = node_a_chan.commit_tx_fee_msat(3);
5014                 let htlc_candidate = HTLCCandidate::new(htlc_amount_msat, HTLCInitiator::LocalOffered);
5015                 let remote_commit_tx_fee = node_a_chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
5016                 assert_eq!(remote_commit_tx_fee, remote_commit_fee_3_htlcs);
5017         }
5018
5019         #[test]
5020         fn test_timeout_vs_success_htlc_dust_limit() {
5021                 // Make sure that when `next_remote_commit_tx_fee_msat` and `next_local_commit_tx_fee_msat`
5022                 // calculate the real dust limits for HTLCs (i.e. the dust limit given by the counterparty
5023                 // *plus* the fees paid for the HTLC) they don't swap `HTLC_SUCCESS_TX_WEIGHT` for
5024                 // `HTLC_TIMEOUT_TX_WEIGHT`, and vice versa.
5025                 let fee_est = TestFeeEstimator{fee_est: 253 };
5026                 let secp_ctx = Secp256k1::new();
5027                 let seed = [42; 32];
5028                 let network = Network::Testnet;
5029                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5030
5031                 let node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5032                 let config = UserConfig::default();
5033                 let mut chan = Channel::<EnforcingSigner>::new_outbound(&&fee_est, &&keys_provider, node_id, 10000000, 100000, 42, &config).unwrap();
5034
5035                 let commitment_tx_fee_0_htlcs = chan.commit_tx_fee_msat(0);
5036                 let commitment_tx_fee_1_htlc = chan.commit_tx_fee_msat(1);
5037
5038                 // If HTLC_SUCCESS_TX_WEIGHT and HTLC_TIMEOUT_TX_WEIGHT were swapped: then this HTLC would be
5039                 // counted as dust when it shouldn't be.
5040                 let htlc_amt_above_timeout = ((253 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + chan.holder_dust_limit_satoshis + 1) * 1000;
5041                 let htlc_candidate = HTLCCandidate::new(htlc_amt_above_timeout, HTLCInitiator::LocalOffered);
5042                 let commitment_tx_fee = chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
5043                 assert_eq!(commitment_tx_fee, commitment_tx_fee_1_htlc);
5044
5045                 // If swapped: this HTLC would be counted as non-dust when it shouldn't be.
5046                 let dust_htlc_amt_below_success = ((253 * HTLC_SUCCESS_TX_WEIGHT / 1000) + chan.holder_dust_limit_satoshis - 1) * 1000;
5047                 let htlc_candidate = HTLCCandidate::new(dust_htlc_amt_below_success, HTLCInitiator::RemoteOffered);
5048                 let commitment_tx_fee = chan.next_local_commit_tx_fee_msat(htlc_candidate, None);
5049                 assert_eq!(commitment_tx_fee, commitment_tx_fee_0_htlcs);
5050
5051                 chan.channel_transaction_parameters.is_outbound_from_holder = false;
5052
5053                 // If swapped: this HTLC would be counted as non-dust when it shouldn't be.
5054                 let dust_htlc_amt_above_timeout = ((253 * HTLC_TIMEOUT_TX_WEIGHT / 1000) + chan.counterparty_dust_limit_satoshis + 1) * 1000;
5055                 let htlc_candidate = HTLCCandidate::new(dust_htlc_amt_above_timeout, HTLCInitiator::LocalOffered);
5056                 let commitment_tx_fee = chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
5057                 assert_eq!(commitment_tx_fee, commitment_tx_fee_0_htlcs);
5058
5059                 // If swapped: this HTLC would be counted as dust when it shouldn't be.
5060                 let htlc_amt_below_success = ((253 * HTLC_SUCCESS_TX_WEIGHT / 1000) + chan.counterparty_dust_limit_satoshis - 1) * 1000;
5061                 let htlc_candidate = HTLCCandidate::new(htlc_amt_below_success, HTLCInitiator::RemoteOffered);
5062                 let commitment_tx_fee = chan.next_remote_commit_tx_fee_msat(htlc_candidate, None);
5063                 assert_eq!(commitment_tx_fee, commitment_tx_fee_1_htlc);
5064         }
5065
5066         #[test]
5067         fn channel_reestablish_no_updates() {
5068                 let feeest = TestFeeEstimator{fee_est: 15000};
5069                 let logger = test_utils::TestLogger::new();
5070                 let secp_ctx = Secp256k1::new();
5071                 let seed = [42; 32];
5072                 let network = Network::Testnet;
5073                 let best_block = BestBlock::from_genesis(network);
5074                 let chain_hash = best_block.block_hash();
5075                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5076
5077                 // Go through the flow of opening a channel between two nodes.
5078
5079                 // Create Node A's channel pointing to Node B's pubkey
5080                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5081                 let config = UserConfig::default();
5082                 let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, 10000000, 100000, 42, &config).unwrap();
5083
5084                 // Create Node B's channel by receiving Node A's open_channel message
5085                 let open_channel_msg = node_a_chan.get_open_channel(chain_hash);
5086                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
5087                 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();
5088
5089                 // Node B --> Node A: accept channel
5090                 let accept_channel_msg = node_b_chan.get_accept_channel();
5091                 node_a_chan.accept_channel(&accept_channel_msg, &config, InitFeatures::known()).unwrap();
5092
5093                 // Node A --> Node B: funding created
5094                 let output_script = node_a_chan.get_funding_redeemscript();
5095                 let tx = Transaction { version: 1, lock_time: 0, input: Vec::new(), output: vec![TxOut {
5096                         value: 10000000, script_pubkey: output_script.clone(),
5097                 }]};
5098                 let funding_outpoint = OutPoint{ txid: tx.txid(), index: 0 };
5099                 let funding_created_msg = node_a_chan.get_outbound_funding_created(tx.clone(), funding_outpoint, &&logger).unwrap();
5100                 let (funding_signed_msg, _) = node_b_chan.funding_created(&funding_created_msg, best_block, &&logger).unwrap();
5101
5102                 // Node B --> Node A: funding signed
5103                 let _ = node_a_chan.funding_signed(&funding_signed_msg, best_block, &&logger);
5104
5105                 // Now disconnect the two nodes and check that the commitment point in
5106                 // Node B's channel_reestablish message is sane.
5107                 node_b_chan.remove_uncommitted_htlcs_and_mark_paused(&&logger);
5108                 let msg = node_b_chan.get_channel_reestablish(&&logger);
5109                 assert_eq!(msg.next_local_commitment_number, 1); // now called next_commitment_number
5110                 assert_eq!(msg.next_remote_commitment_number, 0); // now called next_revocation_number
5111                 match msg.data_loss_protect {
5112                         OptionalField::Present(DataLossProtect { your_last_per_commitment_secret, .. }) => {
5113                                 assert_eq!(your_last_per_commitment_secret, [0; 32]);
5114                         },
5115                         _ => panic!()
5116                 }
5117
5118                 // Check that the commitment point in Node A's channel_reestablish message
5119                 // is sane.
5120                 node_a_chan.remove_uncommitted_htlcs_and_mark_paused(&&logger);
5121                 let msg = node_a_chan.get_channel_reestablish(&&logger);
5122                 assert_eq!(msg.next_local_commitment_number, 1); // now called next_commitment_number
5123                 assert_eq!(msg.next_remote_commitment_number, 0); // now called next_revocation_number
5124                 match msg.data_loss_protect {
5125                         OptionalField::Present(DataLossProtect { your_last_per_commitment_secret, .. }) => {
5126                                 assert_eq!(your_last_per_commitment_secret, [0; 32]);
5127                         },
5128                         _ => panic!()
5129                 }
5130         }
5131
5132         #[test]
5133         fn channel_update() {
5134                 let feeest = TestFeeEstimator{fee_est: 15000};
5135                 let secp_ctx = Secp256k1::new();
5136                 let seed = [42; 32];
5137                 let network = Network::Testnet;
5138                 let chain_hash = genesis_block(network).header.block_hash();
5139                 let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
5140
5141                 // Create a channel.
5142                 let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5143                 let config = UserConfig::default();
5144                 let mut node_a_chan = Channel::<EnforcingSigner>::new_outbound(&&feeest, &&keys_provider, node_b_node_id, 10000000, 100000, 42, &config).unwrap();
5145                 assert!(node_a_chan.counterparty_forwarding_info.is_none());
5146                 assert_eq!(node_a_chan.holder_htlc_minimum_msat, 1); // the default
5147                 assert!(node_a_chan.counterparty_forwarding_info().is_none());
5148
5149                 // Make sure that receiving a channel update will update the Channel as expected.
5150                 let update = ChannelUpdate {
5151                         contents: UnsignedChannelUpdate {
5152                                 chain_hash,
5153                                 short_channel_id: 0,
5154                                 timestamp: 0,
5155                                 flags: 0,
5156                                 cltv_expiry_delta: 100,
5157                                 htlc_minimum_msat: 5,
5158                                 htlc_maximum_msat: OptionalField::Absent,
5159                                 fee_base_msat: 110,
5160                                 fee_proportional_millionths: 11,
5161                                 excess_data: Vec::new(),
5162                         },
5163                         signature: Signature::from(unsafe { FFISignature::new() })
5164                 };
5165                 node_a_chan.channel_update(&update).unwrap();
5166
5167                 // The counterparty can send an update with a higher minimum HTLC, but that shouldn't
5168                 // change our official htlc_minimum_msat.
5169                 assert_eq!(node_a_chan.holder_htlc_minimum_msat, 1);
5170                 match node_a_chan.counterparty_forwarding_info() {
5171                         Some(info) => {
5172                                 assert_eq!(info.cltv_expiry_delta, 100);
5173                                 assert_eq!(info.fee_base_msat, 110);
5174                                 assert_eq!(info.fee_proportional_millionths, 11);
5175                         },
5176                         None => panic!("expected counterparty forwarding info to be Some")
5177                 }
5178         }
5179
5180         #[test]
5181         fn outbound_commitment_test() {
5182                 // Test vectors from BOLT 3 Appendix C:
5183                 let feeest = TestFeeEstimator{fee_est: 15000};
5184                 let logger : Arc<Logger> = Arc::new(test_utils::TestLogger::new());
5185                 let secp_ctx = Secp256k1::new();
5186
5187                 let mut signer = InMemorySigner::new(
5188                         &secp_ctx,
5189                         SecretKey::from_slice(&hex::decode("30ff4956bbdd3222d44cc5e8a1261dab1e07957bdac5ae88fe3261ef321f3749").unwrap()[..]).unwrap(),
5190                         SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(),
5191                         SecretKey::from_slice(&hex::decode("1111111111111111111111111111111111111111111111111111111111111111").unwrap()[..]).unwrap(),
5192                         SecretKey::from_slice(&hex::decode("3333333333333333333333333333333333333333333333333333333333333333").unwrap()[..]).unwrap(),
5193                         SecretKey::from_slice(&hex::decode("1111111111111111111111111111111111111111111111111111111111111111").unwrap()[..]).unwrap(),
5194
5195                         // These aren't set in the test vectors:
5196                         [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],
5197                         10_000_000,
5198                         [0; 32]
5199                 );
5200
5201                 assert_eq!(signer.pubkeys().funding_pubkey.serialize()[..],
5202                                 hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]);
5203                 let keys_provider = Keys { signer: signer.clone() };
5204
5205                 let counterparty_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
5206                 let mut config = UserConfig::default();
5207                 config.channel_options.announced_channel = false;
5208                 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
5209                 chan.holder_dust_limit_satoshis = 546;
5210
5211                 let funding_info = OutPoint{ txid: Txid::from_hex("8984484a580b825b9972d7adb15050b3ab624ccd731946b3eeddb92f4e7ef6be").unwrap(), index: 0 };
5212
5213                 let counterparty_pubkeys = ChannelPublicKeys {
5214                         funding_pubkey: public_from_secret_hex(&secp_ctx, "1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13"),
5215                         revocation_basepoint: PublicKey::from_slice(&hex::decode("02466d7fcae563e5cb09a0d1870bb580344804617879a14949cf22285f1bae3f27").unwrap()[..]).unwrap(),
5216                         payment_point: public_from_secret_hex(&secp_ctx, "4444444444444444444444444444444444444444444444444444444444444444"),
5217                         delayed_payment_basepoint: public_from_secret_hex(&secp_ctx, "1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13"),
5218                         htlc_basepoint: public_from_secret_hex(&secp_ctx, "4444444444444444444444444444444444444444444444444444444444444444")
5219                 };
5220                 chan.channel_transaction_parameters.counterparty_parameters = Some(
5221                         CounterpartyChannelTransactionParameters {
5222                                 pubkeys: counterparty_pubkeys.clone(),
5223                                 selected_contest_delay: 144
5224                         });
5225                 chan.channel_transaction_parameters.funding_outpoint = Some(funding_info);
5226                 signer.ready_channel(&chan.channel_transaction_parameters);
5227
5228                 assert_eq!(counterparty_pubkeys.payment_point.serialize()[..],
5229                            hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
5230
5231                 assert_eq!(counterparty_pubkeys.funding_pubkey.serialize()[..],
5232                            hex::decode("030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c1").unwrap()[..]);
5233
5234                 assert_eq!(counterparty_pubkeys.htlc_basepoint.serialize()[..],
5235                            hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
5236
5237                 // We can't just use build_holder_transaction_keys here as the per_commitment_secret is not
5238                 // derived from a commitment_seed, so instead we copy it here and call
5239                 // build_commitment_transaction.
5240                 let delayed_payment_base = &chan.holder_signer.pubkeys().delayed_payment_basepoint;
5241                 let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
5242                 let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
5243                 let htlc_basepoint = &chan.holder_signer.pubkeys().htlc_basepoint;
5244                 let keys = TxCreationKeys::derive_new(&secp_ctx, &per_commitment_point, delayed_payment_base, htlc_basepoint, &counterparty_pubkeys.revocation_basepoint, &counterparty_pubkeys.htlc_basepoint).unwrap();
5245
5246                 macro_rules! test_commitment {
5247                         ( $counterparty_sig_hex: expr, $sig_hex: expr, $tx_hex: expr, {
5248                                 $( { $htlc_idx: expr, $counterparty_htlc_sig_hex: expr, $htlc_sig_hex: expr, $htlc_tx_hex: expr } ), *
5249                         } ) => { {
5250                                 let (commitment_tx, htlcs): (_, Vec<HTLCOutputInCommitment>) = {
5251                                         let mut res = chan.build_commitment_transaction(0xffffffffffff - 42, &keys, true, false, chan.feerate_per_kw, &logger);
5252
5253                                         let htlcs = res.2.drain(..)
5254                                                 .filter_map(|(htlc, _)| if htlc.transaction_output_index.is_some() { Some(htlc) } else { None })
5255                                                 .collect();
5256                                         (res.0, htlcs)
5257                                 };
5258                                 let trusted_tx = commitment_tx.trust();
5259                                 let unsigned_tx = trusted_tx.built_transaction();
5260                                 let redeemscript = chan.get_funding_redeemscript();
5261                                 let counterparty_signature = Signature::from_der(&hex::decode($counterparty_sig_hex).unwrap()[..]).unwrap();
5262                                 let sighash = unsigned_tx.get_sighash_all(&redeemscript, chan.channel_value_satoshis);
5263                                 secp_ctx.verify(&sighash, &counterparty_signature, chan.counterparty_funding_pubkey()).unwrap();
5264
5265                                 let mut per_htlc: Vec<(HTLCOutputInCommitment, Option<Signature>)> = Vec::new();
5266                                 per_htlc.clear(); // Don't warn about excess mut for no-HTLC calls
5267                                 let mut counterparty_htlc_sigs = Vec::new();
5268                                 counterparty_htlc_sigs.clear(); // Don't warn about excess mut for no-HTLC calls
5269                                 $({
5270                                         let remote_signature = Signature::from_der(&hex::decode($counterparty_htlc_sig_hex).unwrap()[..]).unwrap();
5271                                         per_htlc.push((htlcs[$htlc_idx].clone(), Some(remote_signature)));
5272                                         counterparty_htlc_sigs.push(remote_signature);
5273                                 })*
5274                                 assert_eq!(htlcs.len(), per_htlc.len());
5275
5276                                 let holder_commitment_tx = HolderCommitmentTransaction::new(
5277                                         commitment_tx.clone(),
5278                                         counterparty_signature,
5279                                         counterparty_htlc_sigs,
5280                                         &chan.holder_signer.pubkeys().funding_pubkey,
5281                                         chan.counterparty_funding_pubkey()
5282                                 );
5283                                 let (holder_sig, htlc_sigs) = signer.sign_holder_commitment_and_htlcs(&holder_commitment_tx, &secp_ctx).unwrap();
5284                                 assert_eq!(Signature::from_der(&hex::decode($sig_hex).unwrap()[..]).unwrap(), holder_sig, "holder_sig");
5285
5286                                 let funding_redeemscript = chan.get_funding_redeemscript();
5287                                 let tx = holder_commitment_tx.add_holder_sig(&funding_redeemscript, holder_sig);
5288                                 assert_eq!(serialize(&tx)[..], hex::decode($tx_hex).unwrap()[..], "tx");
5289
5290                                 // ((htlc, counterparty_sig), (index, holder_sig))
5291                                 let mut htlc_sig_iter = holder_commitment_tx.htlcs().iter().zip(&holder_commitment_tx.counterparty_htlc_sigs).zip(htlc_sigs.iter().enumerate());
5292
5293                                 $({
5294                                         let remote_signature = Signature::from_der(&hex::decode($counterparty_htlc_sig_hex).unwrap()[..]).unwrap();
5295
5296                                         let ref htlc = htlcs[$htlc_idx];
5297                                         let htlc_tx = chan.build_htlc_transaction(&unsigned_tx.txid, &htlc, true, &keys, chan.feerate_per_kw);
5298                                         let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys);
5299                                         let htlc_sighash = Message::from_slice(&bip143::SigHashCache::new(&htlc_tx).signature_hash(0, &htlc_redeemscript, htlc.amount_msat / 1000, SigHashType::All)[..]).unwrap();
5300                                         secp_ctx.verify(&htlc_sighash, &remote_signature, &keys.countersignatory_htlc_key).unwrap();
5301
5302                                         let mut preimage: Option<PaymentPreimage> = None;
5303                                         if !htlc.offered {
5304                                                 for i in 0..5 {
5305                                                         let out = PaymentHash(Sha256::hash(&[i; 32]).into_inner());
5306                                                         if out == htlc.payment_hash {
5307                                                                 preimage = Some(PaymentPreimage([i; 32]));
5308                                                         }
5309                                                 }
5310
5311                                                 assert!(preimage.is_some());
5312                                         }
5313
5314                                         let htlc_sig = htlc_sig_iter.next().unwrap();
5315                                         assert_eq!((htlc_sig.0).0.transaction_output_index, Some($htlc_idx), "output index");
5316
5317                                         let signature = Signature::from_der(&hex::decode($htlc_sig_hex).unwrap()[..]).unwrap();
5318                                         assert_eq!(signature, *(htlc_sig.1).1, "htlc sig");
5319                                         let index = (htlc_sig.1).0;
5320                                         let channel_parameters = chan.channel_transaction_parameters.as_holder_broadcastable();
5321                                         let trusted_tx = holder_commitment_tx.trust();
5322                                         assert_eq!(serialize(&trusted_tx.get_signed_htlc_tx(&channel_parameters, index, &(htlc_sig.0).1, (htlc_sig.1).1, &preimage))[..],
5323                                                         hex::decode($htlc_tx_hex).unwrap()[..], "htlc tx");
5324                                 })*
5325                                 assert!(htlc_sig_iter.next().is_none());
5326                         } }
5327                 }
5328
5329                 // simple commitment tx with no HTLCs
5330                 chan.value_to_self_msat = 7000000000;
5331
5332                 test_commitment!("3045022100c3127b33dcc741dd6b05b1e63cbd1a9a7d816f37af9b6756fa2376b056f032370220408b96279808fe57eb7e463710804cdf4f108388bc5cf722d8c848d2c7f9f3b0",
5333                                                  "30440220616210b2cc4d3afb601013c373bbd8aac54febd9f15400379a8cb65ce7deca60022034236c010991beb7ff770510561ae8dc885b8d38d1947248c38f2ae055647142",
5334                                                  "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", {});
5335
5336                 chan.pending_inbound_htlcs.push({
5337                         let mut out = InboundHTLCOutput{
5338                                 htlc_id: 0,
5339                                 amount_msat: 1000000,
5340                                 cltv_expiry: 500,
5341                                 payment_hash: PaymentHash([0; 32]),
5342                                 state: InboundHTLCState::Committed,
5343                         };
5344                         out.payment_hash.0 = Sha256::hash(&hex::decode("0000000000000000000000000000000000000000000000000000000000000000").unwrap()).into_inner();
5345                         out
5346                 });
5347                 chan.pending_inbound_htlcs.push({
5348                         let mut out = InboundHTLCOutput{
5349                                 htlc_id: 1,
5350                                 amount_msat: 2000000,
5351                                 cltv_expiry: 501,
5352                                 payment_hash: PaymentHash([0; 32]),
5353                                 state: InboundHTLCState::Committed,
5354                         };
5355                         out.payment_hash.0 = Sha256::hash(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()).into_inner();
5356                         out
5357                 });
5358                 chan.pending_outbound_htlcs.push({
5359                         let mut out = OutboundHTLCOutput{
5360                                 htlc_id: 2,
5361                                 amount_msat: 2000000,
5362                                 cltv_expiry: 502,
5363                                 payment_hash: PaymentHash([0; 32]),
5364                                 state: OutboundHTLCState::Committed,
5365                                 source: HTLCSource::dummy(),
5366                         };
5367                         out.payment_hash.0 = Sha256::hash(&hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap()).into_inner();
5368                         out
5369                 });
5370                 chan.pending_outbound_htlcs.push({
5371                         let mut out = OutboundHTLCOutput{
5372                                 htlc_id: 3,
5373                                 amount_msat: 3000000,
5374                                 cltv_expiry: 503,
5375                                 payment_hash: PaymentHash([0; 32]),
5376                                 state: OutboundHTLCState::Committed,
5377                                 source: HTLCSource::dummy(),
5378                         };
5379                         out.payment_hash.0 = Sha256::hash(&hex::decode("0303030303030303030303030303030303030303030303030303030303030303").unwrap()).into_inner();
5380                         out
5381                 });
5382                 chan.pending_inbound_htlcs.push({
5383                         let mut out = InboundHTLCOutput{
5384                                 htlc_id: 4,
5385                                 amount_msat: 4000000,
5386                                 cltv_expiry: 504,
5387                                 payment_hash: PaymentHash([0; 32]),
5388                                 state: InboundHTLCState::Committed,
5389                         };
5390                         out.payment_hash.0 = Sha256::hash(&hex::decode("0404040404040404040404040404040404040404040404040404040404040404").unwrap()).into_inner();
5391                         out
5392                 });
5393
5394                 // commitment tx with all five HTLCs untrimmed (minimum feerate)
5395                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5396                 chan.feerate_per_kw = 0;
5397
5398                 test_commitment!("3044022009b048187705a8cbc9ad73adbe5af148c3d012e1f067961486c822c7af08158c022006d66f3704cfab3eb2dc49dae24e4aa22a6910fc9b424007583204e3621af2e5",
5399                                  "304402206fc2d1f10ea59951eefac0b4b7c396a3c3d87b71ff0b019796ef4535beaf36f902201765b0181e514d04f4c8ad75659d7037be26cdb3f8bb6f78fe61decef484c3ea",
5400                                  "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", {
5401
5402                                   { 0,
5403                                   "3045022100d9e29616b8f3959f1d3d7f7ce893ffedcdc407717d0de8e37d808c91d3a7c50d022078c3033f6d00095c8720a4bc943c1b45727818c082e4e3ddbc6d3116435b624b",
5404                                   "30440220636de5682ef0c5b61f124ec74e8aa2461a69777521d6998295dcea36bc3338110220165285594b23c50b28b82df200234566628a27bcd17f7f14404bd865354eb3ce",
5405                                   "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" },
5406
5407                                   { 1,
5408                                   "30440220649fe8b20e67e46cbb0d09b4acea87dbec001b39b08dee7bdd0b1f03922a8640022037c462dff79df501cecfdb12ea7f4de91f99230bb544726f6e04527b1f896004",
5409                                   "3045022100803159dee7935dba4a1d36a61055ce8fd62caa528573cc221ae288515405a252022029c59e7cffce374fe860100a4a63787e105c3cf5156d40b12dd53ff55ac8cf3f",
5410                                   "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" },
5411
5412                                   { 2,
5413                                   "30440220770fc321e97a19f38985f2e7732dd9fe08d16a2efa4bcbc0429400a447faf49102204d40b417f3113e1b0944ae0986f517564ab4acd3d190503faf97a6e420d43352",
5414                                   "3045022100a437cc2ce77400ecde441b3398fea3c3ad8bdad8132be818227fe3c5b8345989022069d45e7fa0ae551ec37240845e2c561ceb2567eacf3076a6a43a502d05865faa",
5415                                   "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" },
5416
5417                                   { 3,
5418                                   "304402207bcbf4f60a9829b05d2dbab84ed593e0291836be715dc7db6b72a64caf646af802201e489a5a84f7c5cc130398b841d138d031a5137ac8f4c49c770a4959dc3c1363",
5419                                   "304402203121d9b9c055f354304b016a36662ee99e1110d9501cb271b087ddb6f382c2c80220549882f3f3b78d9c492de47543cb9a697cecc493174726146536c5954dac7487",
5420                                   "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" },
5421
5422                                   { 4,
5423                                   "3044022076dca5cb81ba7e466e349b7128cdba216d4d01659e29b96025b9524aaf0d1899022060de85697b88b21c749702b7d2cfa7dfeaa1f472c8f1d7d9c23f2bf968464b87",
5424                                   "3045022100d9080f103cc92bac15ec42464a95f070c7fb6925014e673ee2ea1374d36a7f7502200c65294d22eb20d48564954d5afe04a385551919d8b2ddb4ae2459daaeee1d95",
5425                                   "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" }
5426                 } );
5427
5428                 // commitment tx with seven outputs untrimmed (maximum feerate)
5429                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5430                 chan.feerate_per_kw = 647;
5431
5432                 test_commitment!("3045022100a135f9e8a5ed25f7277446c67956b00ce6f610ead2bdec2c2f686155b7814772022059f1f6e1a8b336a68efcc1af3fe4d422d4827332b5b067501b099c47b7b5b5ee",
5433                                  "30450221009ec15c687898bb4da8b3a833e5ab8bfc51ec6e9202aaa8e66611edfd4a85ed1102203d7183e45078b9735c93450bc3415d3e5a8c576141a711ec6ddcb4a893926bb7",
5434                                  "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", {
5435
5436                                   { 0,
5437                                   "30450221008437627f9ad84ac67052e2a414a4367b8556fd1f94d8b02590f89f50525cd33502205b9c21ff6e7fc864f2352746ad8ba59182510819acb644e25b8a12fc37bbf24f",
5438                                   "30440220344b0deb055230d01703e6c7acd45853c4af2328b49b5d8af4f88a060733406602202ea64f2a43d5751edfe75503cbc35a62e3141b5ed032fa03360faf4ca66f670b",
5439                                   "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" },
5440
5441                                   { 1,
5442                                   "304402205a67f92bf6845cf2892b48d874ac1daf88a36495cf8a06f93d83180d930a6f75022031da1621d95c3f335cc06a3056cf960199dae600b7cf89088f65fc53cdbef28c",
5443                                   "30450221009e5e3822b0185c6799a95288c597b671d6cc69ab80f43740f00c6c3d0752bdda02206da947a74bd98f3175324dc56fdba86cc783703a120a6f0297537e60632f4c7f",
5444                                   "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" },
5445
5446                                   { 2,
5447                                   "30440220437e21766054a3eef7f65690c5bcfa9920babbc5af92b819f772f6ea96df6c7402207173622024bd97328cfb26c6665e25c2f5d67c319443ccdc60c903217005d8c8",
5448                                   "3045022100fcfc47e36b712624677626cef3dc1d67f6583bd46926a6398fe6b00b0c9a37760220525788257b187fc775c6370d04eadf34d06f3650a63f8df851cee0ecb47a1673",
5449                                   "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" },
5450
5451                                   { 3,
5452                                   "304402207436e10737e4df499fc051686d3e11a5bb2310e4d1f1e691d287cef66514791202207cb58e71a6b7a42dd001b7e3ae672ea4f71ea3e1cd412b742e9124abb0739c64",
5453                                   "3045022100e78211b8409afb7255ffe37337da87f38646f1faebbdd61bc1920d69e3ead67a02201a626305adfcd16bfb7e9340928d9b6305464eab4aa4c4a3af6646e9b9f69dee",
5454                                   "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" },
5455
5456                                   { 4,
5457                                   "30450221009acd6a827a76bfee50806178dfe0495cd4e1d9c58279c194c7b01520fe68cb8d022024d439047c368883e570997a7d40f0b430cb5a742f507965e7d3063ae3feccca",
5458                                   "3044022048762cf546bbfe474f1536365ea7c416e3c0389d60558bc9412cb148fb6ab68202207215d7083b75c96ff9d2b08c59c34e287b66820f530b486a9aa4cdd9c347d5b9",
5459                                   "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" }
5460                 } );
5461
5462                 // commitment tx with six outputs untrimmed (minimum feerate)
5463                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5464                 chan.feerate_per_kw = 648;
5465
5466                 test_commitment!("304402203948f900a5506b8de36a4d8502f94f21dd84fd9c2314ab427d52feaa7a0a19f2022059b6a37a4adaa2c5419dc8aea63c6e2a2ec4c4bde46207f6dc1fcd22152fc6e5",
5467                                  "3045022100b15f72908ba3382a34ca5b32519240a22300cc6015b6f9418635fb41f3d01d8802207adb331b9ed1575383dca0f2355e86c173802feecf8298fbea53b9d4610583e9",
5468                                  "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", {
5469
5470                                   { 0,
5471                                   "3045022100a031202f3be94678f0e998622ee95ebb6ada8da1e9a5110228b5e04a747351e4022010ca6a21e18314ed53cfaae3b1f51998552a61a468e596368829a50ce40110e0",
5472                                   "304502210097e1873b57267730154595187a34949d3744f52933070c74757005e61ce2112e02204ecfba2aa42d4f14bdf8bad4206bb97217b702e6c433e0e1b0ce6587e6d46ec6",
5473                                   "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" },
5474
5475                                   { 1,
5476                                   "304402202361012a634aee7835c5ecdd6413dcffa8f404b7e77364c792cff984e4ee71e90220715c5e90baa08daa45a7439b1ee4fa4843ed77b19c058240b69406606d384124",
5477                                   "3044022019de73b00f1d818fb388e83b2c8c31f6bce35ac624e215bc12f88f9dc33edf48022006ff814bb9f700ee6abc3294e146fac3efd4f13f0005236b41c0a946ee00c9ae",
5478                                   "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" },
5479
5480                                   { 2,
5481                                   "304402207e8e82cd71ed4febeb593732c260456836e97d81896153ecd2b3cf320ca6861702202dd4a30f68f98ced7cc56a36369ac1fdd978248c5ff4ed204fc00cc625532989",
5482                                   "3045022100bd0be6100c4fd8f102ec220e1b053e4c4e2ecca25615490150007b40d314dc3902201a1e0ea266965b43164d9e6576f58fa6726d42883dd1c3996d2925c2e2260796",
5483                                   "020000000001010f44041fdfba175987cf4e6135ba2a154e3b7fb96483dc0ed5efc0678e5b6bf1020000000000000000010b0a0000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e050047304402207e8e82cd71ed4febeb593732c260456836e97d81896153ecd2b3cf320ca6861702202dd4a30f68f98ced7cc56a36369ac1fdd978248c5ff4ed204fc00cc62553298901483045022100bd0be6100c4fd8f102ec220e1b053e4c4e2ecca25615490150007b40d314dc3902201a1e0ea266965b43164d9e6576f58fa6726d42883dd1c3996d2925c2e226079601008576a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c820120876475527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae67a9148a486ff2e31d6158bf39e2608864d63fefd09d5b88ac6868f7010000" },
5484
5485                                   { 3,
5486                                   "3044022024cd52e4198c8ae0e414a86d86b5a65ea7450f2eb4e783096736d93395eca5ce022078f0094745b45be4d4b2b04dd5978c9e66ba49109e5704403e84aaf5f387d6be",
5487                                   "3045022100bbfb9d0a946d420807c86e985d636cceb16e71c3694ed186316251a00cbd807202207773223f9a337e145f64673825be9b30d07ef1542c82188b264bedcf7cda78c6",
5488                                   "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" }
5489                 } );
5490
5491                 // commitment tx with six outputs untrimmed (maximum feerate)
5492                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5493                 chan.feerate_per_kw = 2069;
5494
5495                 test_commitment!("304502210090b96a2498ce0c0f2fadbec2aab278fed54c1a7838df793ec4d2c78d96ec096202204fdd439c50f90d483baa7b68feeef4bd33bc277695405447bcd0bfb2ca34d7bc",
5496                                  "3045022100ad9a9bbbb75d506ca3b716b336ee3cf975dd7834fcf129d7dd188146eb58a8b4022061a759ee417339f7fe2ea1e8deb83abb6a74db31a09b7648a932a639cda23e33",
5497                                  "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", {
5498
5499                                   { 0,
5500                                   "3045022100f33513ee38abf1c582876f921f8fddc06acff48e04515532a32d3938de938ffd02203aa308a2c1863b7d6fdf53159a1465bf2e115c13152546cc5d74483ceaa7f699",
5501                                   "3045022100a637902a5d4c9ba9e7c472a225337d5aac9e2e3f6744f76e237132e7619ba0400220035c60d784a031c0d9f6df66b7eab8726a5c25397399ee4aa960842059eb3f9d",
5502                                   "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" },
5503
5504                                   { 1,
5505                                   "3045022100ce07682cf4b90093c22dc2d9ab2a77ad6803526b655ef857221cc96af5c9e0bf02200f501cee22e7a268af40b555d15a8237c9f36ad67ef1841daf9f6a0267b1e6df",
5506                                   "3045022100e57e46234f8782d3ff7aa593b4f7446fb5316c842e693dc63ee324fd49f6a1c302204a2f7b44c48bd26e1554422afae13153eb94b29d3687b733d18930615fb2db61",
5507                                   "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" },
5508
5509                                   { 2,
5510                                   "3045022100e3e35492e55f82ec0bc2f317ffd7a486d1f7024330fe9743c3559fc39f32ef0c02203d1d4db651fc388a91d5ad8ecdd8e83673063bc8eefe27cfd8c189090e3a23e0",
5511                                   "3044022068613fb1b98eb3aec7f44c5b115b12343c2f066c4277c82b5f873dfe68f37f50022028109b4650f3f528ca4bfe9a467aff2e3e43893b61b5159157119d5d95cf1c18",
5512                                   "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" },
5513
5514                                   { 3,
5515                                   "304402207475aeb0212ef9bf5130b60937817ad88c9a87976988ef1f323f026148cc4a850220739fea17ad3257dcad72e509c73eebe86bee30b178467b9fdab213d631b109df",
5516                                   "3045022100d315522e09e7d53d2a659a79cb67fef56d6c4bddf3f46df6772d0d20a7beb7c8022070bcc17e288607b6a72be0bd83368bb6d53488db266c1cdb4d72214e4f02ac33",
5517                                   "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" }
5518                 } );
5519
5520                 // commitment tx with five outputs untrimmed (minimum feerate)
5521                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5522                 chan.feerate_per_kw = 2070;
5523
5524                 test_commitment!("304402204ca1ba260dee913d318271d86e10ca0f5883026fb5653155cff600fb40895223022037b145204b7054a40e08bb1fefbd826f827b40838d3e501423bcc57924bcb50c",
5525                                  "3044022001014419b5ba00e083ac4e0a85f19afc848aacac2d483b4b525d15e2ae5adbfe022015ebddad6ee1e72b47cb09f3e78459da5be01ccccd95dceca0e056a00cc773c1",
5526                                  "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", {
5527
5528                                   { 0,
5529                                   "304402205f6b6d12d8d2529fb24f4445630566cf4abbd0f9330ab6c2bdb94222d6a2a0c502202f556258ae6f05b193749e4c541dfcc13b525a5422f6291f073f15617ba8579b",
5530                                   "30440220150b11069454da70caf2492ded9e0065c9a57f25ac2a4c52657b1d15b6c6ed85022068a38833b603c8892717206383611bad210f1cbb4b1f87ea29c6c65b9e1cb3e5",
5531                                   "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" },
5532
5533                                   { 1,
5534                                   "3045022100f960dfb1c9aee7ce1437efa65b523e399383e8149790e05d8fed27ff6e42fe0002202fe8613e062ffe0b0c518cc4101fba1c6de70f64a5bcc7ae663f2efae43b8546",
5535                                   "30450221009a6ed18e6873bc3644332a6ee21c152a5b102821865350df7a8c74451a51f9f2022050d801fb4895d7d7fbf452824c0168347f5c0cbe821cf6a97a63af5b8b2563c6",
5536                                   "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" },
5537
5538                                   { 2,
5539                                   "3045022100ae5fc7717ae684bc1fcf9020854e5dbe9842c9e7472879ac06ff95ac2bb10e4e022057728ada4c00083a3e65493fb5d50a232165948a1a0f530ef63185c2c8c56504",
5540                                   "30440220408ad3009827a8fccf774cb285587686bfb2ed041f89a89453c311ce9c8ee0f902203c7392d9f8306d3a46522a66bd2723a7eb2628cb2d9b34d4c104f1766bf37502",
5541                                   "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" }
5542                 } );
5543
5544                 // commitment tx with five outputs untrimmed (maximum feerate)
5545                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5546                 chan.feerate_per_kw = 2194;
5547
5548                 test_commitment!("304402204bb3d6e279d71d9da414c82de42f1f954267c762b2e2eb8b76bc3be4ea07d4b0022014febc009c5edc8c3fc5d94015de163200f780046f1c293bfed8568f08b70fb3",
5549                                  "3044022072c2e2b1c899b2242656a537dde2892fa3801be0d6df0a87836c550137acde8302201654aa1974d37a829083c3ba15088689f30b56d6a4f6cb14c7bad0ee3116d398",
5550                                  "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", {
5551
5552                                   { 0,
5553                                   "3045022100939726680351a7856c1bc386d4a1f422c7d29bd7b56afc139570f508474e6c40022023175a799ccf44c017fbaadb924c40b2a12115a5b7d0dfd3228df803a2de8450",
5554                                   "304502210099c98c2edeeee6ec0fb5f3bea8b79bb016a2717afa9b5072370f34382de281d302206f5e2980a995e045cf90a547f0752a7ee99d48547bc135258fe7bc07e0154301",
5555                                   "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" },
5556
5557                                   { 1,
5558                                   "3044022021bb883bf324553d085ba2e821cad80c28ef8b303dbead8f98e548783c02d1600220638f9ef2a9bba25869afc923f4b5dc38be3bb459f9efa5d869392d5f7779a4a0",
5559                                   "3045022100fd85bd7697b89c08ec12acc8ba89b23090637d83abd26ca37e01ae93e67c367302202b551fe69386116c47f984aab9c8dfd25d864dcde5d3389cfbef2447a85c4b77",
5560                                   "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" },
5561
5562                                   { 2,
5563                                   "3045022100c9e6f0454aa598b905a35e641a70cc9f67b5f38cc4b00843a041238c4a9f1c4a0220260a2822a62da97e44583e837245995ca2e36781769c52f19e498efbdcca262b",
5564                                   "30450221008a9f2ea24cd455c2b64c1472a5fa83865b0a5f49a62b661801e884cf2849af8302204d44180e50bf6adfcf1c1e581d75af91aba4e28681ce4a5ee5f3cbf65eca10f3",
5565                                   "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" }
5566                 } );
5567
5568                 // commitment tx with four outputs untrimmed (minimum feerate)
5569                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5570                 chan.feerate_per_kw = 2195;
5571
5572                 test_commitment!("304402201a8c1b1f9671cd9e46c7323a104d7047cc48d3ee80d40d4512e0c72b8dc65666022066d7f9a2ce18c9eb22d2739ffcce05721c767f9b607622a31b6ea5793ddce403",
5573                                  "3044022044d592025b610c0d678f65032e87035cdfe89d1598c522cc32524ae8172417c30220749fef9d5b2ae8cdd91ece442ba8809bc891efedae2291e578475f97715d1767",
5574                                  "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", {
5575
5576                                   { 0,
5577                                   "3045022100e57b845066a06ee7c2cbfc29eabffe52daa9bf6f6de760066d04df9f9b250e0002202ffb197f0e6e0a77a75a9aff27014bd3de83b7f748d7efef986abe655e1dd50e",
5578                                   "3045022100ecc8c6529d0b2316d046f0f0757c1e1c25a636db168ec4f3aa1b9278df685dc0022067ae6b65e936f1337091f7b18a15935b608c5f2cdddb2f892ed0babfdd376d76",
5579                                   "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" },
5580
5581                                   { 1,
5582                                   "3045022100d193b7ecccad8057571620a0b1ffa6c48e9483311723b59cf536043b20bc51550220546d4bd37b3b101ecda14f6c907af46ec391abce1cd9c7ce22b1a62b534f2f2a",
5583                                   "3044022014d66f11f9cacf923807eba49542076c5fe5cccf252fb08fe98c78ef3ca6ab5402201b290dbe043cc512d9d78de074a5a129b8759bc6a6c546b190d120b690bd6e82",
5584                                   "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" }
5585                 } );
5586
5587                 // commitment tx with four outputs untrimmed (maximum feerate)
5588                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5589                 chan.feerate_per_kw = 3702;
5590
5591                 test_commitment!("304502210092a587aeb777f869e7ff0d7898ea619ee26a3dacd1f3672b945eea600be431100220077ee9eae3528d15251f2a52b607b189820e57a6ccfac8d1af502b132ee40169",
5592                                  "3045022100e5efb73c32d32da2d79702299b6317de6fb24a60476e3855926d78484dd1b3c802203557cb66a42c944ef06e00bcc4da35a5bcb2f185aab0f8e403e519e1d66aaf75",
5593                                  "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", {
5594
5595                                   { 0,
5596                                   "304402206fa54c11f98c3bae1e93df43fc7affeb05b476bf8060c03e29c377c69bc08e8b0220672701cce50d5c379ff45a5d2cfe48ac44973adb066ac32608e21221d869bb89",
5597                                   "304402206e36c683ebf2cb16bcef3d5439cf8b53cd97280a365ed8acd7abb85a8ba5f21c02206e8621edfc2a5766cbc96eb67fd501127ff163eb6b85518a39f7d4974aef126f",
5598                                   "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" },
5599
5600                                   { 1,
5601                                   "3044022057649739b0eb74d541ead0dfdb3d4b2c15aa192720031044c3434c67812e5ca902201e5ede42d960ae551707f4a6b34b09393cf4dee2418507daa022e3550dbb5817",
5602                                   "304402207faad26678c8850e01b4a0696d60841f7305e1832b786110ee9075cb92ed14a30220516ef8ee5dfa80824ea28cbcec0dd95f8b847146257c16960db98507db15ffdc",
5603                                   "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" }
5604                 } );
5605
5606                 // commitment tx with three outputs untrimmed (minimum feerate)
5607                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5608                 chan.feerate_per_kw = 3703;
5609
5610                 test_commitment!("3045022100b495d239772a237ff2cf354b1b11be152fd852704cb184e7356d13f2fb1e5e430220723db5cdb9cbd6ead7bfd3deb419cf41053a932418cbb22a67b581f40bc1f13e",
5611                                  "304402201b736d1773a124c745586217a75bed5f66c05716fbe8c7db4fdb3c3069741cdd02205083f39c321c1bcadfc8d97e3c791a66273d936abac0c6a2fde2ed46019508e1",
5612                                  "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", {
5613
5614                                   { 0,
5615                                   "3045022100c34c61735f93f2e324cc873c3b248111ccf8f6db15d5969583757010d4ad2b4602207867bb919b2ddd6387873e425345c9b7fd18d1d66aba41f3607bc2896ef3c30a",
5616                                   "3045022100988c143e2110067117d2321bdd4bd16ca1734c98b29290d129384af0962b634e02206c1b02478878c5f547018b833986578f90c3e9be669fe5788ad0072a55acbb05",
5617                                   "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" }
5618                 } );
5619
5620                 // commitment tx with three outputs untrimmed (maximum feerate)
5621                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5622                 chan.feerate_per_kw = 4914;
5623
5624                 test_commitment!("3045022100b4b16d5f8cc9fc4c1aff48831e832a0d8990e133978a66e302c133550954a44d022073573ce127e2200d316f6b612803a5c0c97b8d20e1e44dbe2ac0dd2fb8c95244",
5625                                  "3045022100d72638bc6308b88bb6d45861aae83e5b9ff6e10986546e13bce769c70036e2620220320be7c6d66d22f30b9fcd52af66531505b1310ca3b848c19285b38d8a1a8c19",
5626                                  "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", {
5627
5628                                   { 0,
5629                                   "3045022100f43591c156038ba217756006bb3c55f7d113a325cdd7d9303c82115372858d68022016355b5aadf222bc8d12e426c75f4a03423917b2443a103eb2a498a3a2234374",
5630                                   "30440220585dee80fafa264beac535c3c0bb5838ac348b156fdc982f86adc08dfc9bfd250220130abb82f9f295cc9ef423dcfef772fde2acd85d9df48cc538981d26a10a9c10",
5631                                   "02000000000101a9172908eace869cc35128c31fc2ab502f72e4dff31aab23e0244c4b04b11ab00000000000000000000122020000000000002200204adb4e2f00643db396dd120d4e7dc17625f5f2c11a40d857accc862d6b7dd80e0500483045022100f43591c156038ba217756006bb3c55f7d113a325cdd7d9303c82115372858d68022016355b5aadf222bc8d12e426c75f4a03423917b2443a103eb2a498a3a2234374014730440220585dee80fafa264beac535c3c0bb5838ac348b156fdc982f86adc08dfc9bfd250220130abb82f9f295cc9ef423dcfef772fde2acd85d9df48cc538981d26a10a9c10012004040404040404040404040404040404040404040404040404040404040404048a76a91414011f7254d96b819c76986c277d115efce6f7b58763ac67210394854aa6eab5b2a8122cc726e9dded053a2184d88256816826d6231c068d4a5b7c8201208763a91418bc1a114ccf9c052d3d23e28d3b0a9d1227434288527c21030d417a46946384f88d5f3337267c5e579765875dc4daca813e21734b140639e752ae677502f801b175ac686800000000" }
5632                 } );
5633
5634                 // commitment tx with two outputs untrimmed (minimum feerate)
5635                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5636                 chan.feerate_per_kw = 4915;
5637
5638                 test_commitment!("304402203a286936e74870ca1459c700c71202af0381910a6bfab687ef494ef1bc3e02c902202506c362d0e3bee15e802aa729bf378e051644648253513f1c085b264cc2a720",
5639                                  "30450221008a953551f4d67cb4df3037207fc082ddaf6be84d417b0bd14c80aab66f1b01a402207508796dc75034b2dee876fe01dc05a08b019f3e5d689ac8842ade2f1befccf5",
5640                                  "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", {});
5641
5642                 // commitment tx with two outputs untrimmed (maximum feerate)
5643                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5644                 chan.feerate_per_kw = 9651180;
5645
5646                 test_commitment!("304402200a8544eba1d216f5c5e530597665fa9bec56943c0f66d98fc3d028df52d84f7002201e45fa5c6bc3a506cc2553e7d1c0043a9811313fc39c954692c0d47cfce2bbd3",
5647                                  "3045022100e11b638c05c650c2f63a421d36ef8756c5ce82f2184278643520311cdf50aa200220259565fb9c8e4a87ccaf17f27a3b9ca4f20625754a0920d9c6c239d8156a11de",
5648                                  "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", {});
5649
5650                 // commitment tx with one output untrimmed (minimum feerate)
5651                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5652                 chan.feerate_per_kw = 9651181;
5653
5654                 test_commitment!("304402202ade0142008309eb376736575ad58d03e5b115499709c6db0b46e36ff394b492022037b63d78d66404d6504d4c4ac13be346f3d1802928a6d3ad95a6a944227161a2",
5655                                  "304402207e8d51e0c570a5868a78414f4e0cbfaed1106b171b9581542c30718ee4eb95ba02203af84194c97adf98898c9afe2f2ed4a7f8dba05a2dfab28ac9d9c604aa49a379",
5656                                  "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", {});
5657
5658                 // commitment tx with fee greater than funder amount
5659                 chan.value_to_self_msat = 6993000000; // 7000000000 - 7000000
5660                 chan.feerate_per_kw = 9651936;
5661
5662                 test_commitment!("304402202ade0142008309eb376736575ad58d03e5b115499709c6db0b46e36ff394b492022037b63d78d66404d6504d4c4ac13be346f3d1802928a6d3ad95a6a944227161a2",
5663                                  "304402207e8d51e0c570a5868a78414f4e0cbfaed1106b171b9581542c30718ee4eb95ba02203af84194c97adf98898c9afe2f2ed4a7f8dba05a2dfab28ac9d9c604aa49a379",
5664                                  "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", {});
5665
5666                 // commitment tx with 3 htlc outputs, 2 offered having the same amount and preimage
5667                 chan.value_to_self_msat = 7_000_000_000 - 2_000_000;
5668                 chan.feerate_per_kw = 253;
5669                 chan.pending_inbound_htlcs.clear();
5670                 chan.pending_inbound_htlcs.push({
5671                         let mut out = InboundHTLCOutput{
5672                                 htlc_id: 1,
5673                                 amount_msat: 2000000,
5674                                 cltv_expiry: 501,
5675                                 payment_hash: PaymentHash([0; 32]),
5676                                 state: InboundHTLCState::Committed,
5677                         };
5678                         out.payment_hash.0 = Sha256::hash(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()).into_inner();
5679                         out
5680                 });
5681                 chan.pending_outbound_htlcs.clear();
5682                 chan.pending_outbound_htlcs.push({
5683                         let mut out = OutboundHTLCOutput{
5684                                 htlc_id: 6,
5685                                 amount_msat: 5000000,
5686                                 cltv_expiry: 506,
5687                                 payment_hash: PaymentHash([0; 32]),
5688                                 state: OutboundHTLCState::Committed,
5689                                 source: HTLCSource::dummy(),
5690                         };
5691                         out.payment_hash.0 = Sha256::hash(&hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()).into_inner();
5692                         out
5693                 });
5694                 chan.pending_outbound_htlcs.push({
5695                         let mut out = OutboundHTLCOutput{
5696                                 htlc_id: 5,
5697                                 amount_msat: 5000000,
5698                                 cltv_expiry: 505,
5699                                 payment_hash: PaymentHash([0; 32]),
5700                                 state: OutboundHTLCState::Committed,
5701                                 source: HTLCSource::dummy(),
5702                         };
5703                         out.payment_hash.0 = Sha256::hash(&hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()).into_inner();
5704                         out
5705                 });
5706
5707                 test_commitment!("30440220048705bec5288d28b3f29344b8d124853b1af423a568664d2c6f02c8ea886525022060f998a461052a2476b912db426ea2a06700953a241135c7957f2e79bc222df9",
5708                                  "3045022100c4f1d60b6fca9febc8b39de1a31e84c5f7c4b41c97239ef05f4350aa484c6b5e02200c5134ac8b20eb7a29d0dd4a501f6aa8fefb8489171f4cb408bd2a32324ab03f",
5709                                  "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", {
5710
5711                                   { 0,
5712                                   "304502210081cbb94121761d34c189cd4e6a281feea6f585060ad0ba2632e8d6b3c6bb8a6c02201007981bbd16539d63df2805b5568f1f5688cd2a885d04706f50db9b77ba13c6",
5713                                   "304502210090ed76aeb21b53236a598968abc66e2024691d07b62f53ddbeca8f93144af9c602205f873af5a0c10e62690e9aba09740550f194a9dc455ba4c1c23f6cde7704674c",
5714                                   "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" },
5715                                   { 1,
5716                                   "304402201d0f09d2bf7bc245a4f17980e1e9164290df16c70c6a2ff1592f5030d6108581022061e744a7dc151b36bf0aff7a4f1812ba90b8b03633bb979a270d19858fd960c5",
5717                                   "30450221009aef000d2e843a4202c1b1a2bf554abc9a7902bf49b2cb0759bc507456b7ebad02204e7c3d193ede2fd2b4cd6b39f51a920e581e35575e357e44d7b699c40ce61d39",
5718                                   "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" },
5719                                   { 2,
5720                                   "30440220010bf035d5823596e50dce2076a4d9f942d8d28031c9c428b901a02b6b8140de02203250e8e4a08bc5b4ecdca4d0eedf98223e02e3ac1c0206b3a7ffdb374aa21e5f",
5721                                   "30440220073de0067b88e425b3018b30366bfeda0ccb703118ccd3d02ead08c0f53511d002203fac50ac0e4cf8a3af0b4b1b12e801650591f748f8ddf1e089c160f10b69e511",
5722                                   "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" }
5723                 } );
5724         }
5725
5726         #[test]
5727         fn test_per_commitment_secret_gen() {
5728                 // Test vectors from BOLT 3 Appendix D:
5729
5730                 let mut seed = [0; 32];
5731                 seed[0..32].clone_from_slice(&hex::decode("0000000000000000000000000000000000000000000000000000000000000000").unwrap());
5732                 assert_eq!(chan_utils::build_commitment_secret(&seed, 281474976710655),
5733                            hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap()[..]);
5734
5735                 seed[0..32].clone_from_slice(&hex::decode("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF").unwrap());
5736                 assert_eq!(chan_utils::build_commitment_secret(&seed, 281474976710655),
5737                            hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap()[..]);
5738
5739                 assert_eq!(chan_utils::build_commitment_secret(&seed, 0xaaaaaaaaaaa),
5740                            hex::decode("56f4008fb007ca9acf0e15b054d5c9fd12ee06cea347914ddbaed70d1c13a528").unwrap()[..]);
5741
5742                 assert_eq!(chan_utils::build_commitment_secret(&seed, 0x555555555555),
5743                            hex::decode("9015daaeb06dba4ccc05b91b2f73bd54405f2be9f217fbacd3c5ac2e62327d31").unwrap()[..]);
5744
5745                 seed[0..32].clone_from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap());
5746                 assert_eq!(chan_utils::build_commitment_secret(&seed, 1),
5747                            hex::decode("915c75942a26bb3a433a8ce2cb0427c29ec6c1775cfc78328b57f6ba7bfeaa9c").unwrap()[..]);
5748         }
5749
5750         #[test]
5751         fn test_key_derivation() {
5752                 // Test vectors from BOLT 3 Appendix E:
5753                 let secp_ctx = Secp256k1::new();
5754
5755                 let base_secret = SecretKey::from_slice(&hex::decode("000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f").unwrap()[..]).unwrap();
5756                 let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
5757
5758                 let base_point = PublicKey::from_secret_key(&secp_ctx, &base_secret);
5759                 assert_eq!(base_point.serialize()[..], hex::decode("036d6caac248af96f6afa7f904f550253a0f3ef3f5aa2fe6838a95b216691468e2").unwrap()[..]);
5760
5761                 let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
5762                 assert_eq!(per_commitment_point.serialize()[..], hex::decode("025f7117a78150fe2ef97db7cfc83bd57b2e2c0d0dd25eaf467a4a1c2a45ce1486").unwrap()[..]);
5763
5764                 assert_eq!(chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &base_point).unwrap().serialize()[..],
5765                                 hex::decode("0235f2dbfaa89b57ec7b055afe29849ef7ddfeb1cefdb9ebdc43f5494984db29e5").unwrap()[..]);
5766
5767                 assert_eq!(chan_utils::derive_private_key(&secp_ctx, &per_commitment_point, &base_secret).unwrap(),
5768                                 SecretKey::from_slice(&hex::decode("cbced912d3b21bf196a766651e436aff192362621ce317704ea2f75d87e7be0f").unwrap()[..]).unwrap());
5769
5770                 assert_eq!(chan_utils::derive_public_revocation_key(&secp_ctx, &per_commitment_point, &base_point).unwrap().serialize()[..],
5771                                 hex::decode("02916e326636d19c33f13e8c0c3a03dd157f332f3e99c317c141dd865eb01f8ff0").unwrap()[..]);
5772
5773                 assert_eq!(chan_utils::derive_private_revocation_key(&secp_ctx, &per_commitment_secret, &base_secret).unwrap(),
5774                                 SecretKey::from_slice(&hex::decode("d09ffff62ddb2297ab000cc85bcb4283fdeb6aa052affbc9dddcf33b61078110").unwrap()[..]).unwrap());
5775         }
5776 }