1 // This file is Copyright its original authors, visible in version control
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
10 //! The logic to monitor for on-chain transactions and create the relevant claim responses lives
13 //! ChannelMonitor objects are generated by ChannelManager in response to relevant
14 //! messages/actions, and MUST be persisted to disk (and, preferably, remotely) before progress can
15 //! be made in responding to certain messages, see [`chain::Watch`] for more.
17 //! Note that ChannelMonitors are an important part of the lightning trust model and a copy of the
18 //! latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date
19 //! ChannelMonitors should do so). Thus, if you're building rust-lightning into an HSM or other
20 //! security-domain-separated system design, you should consider having multiple paths for
21 //! ChannelMonitors to get out of the HSM and onto monitoring devices.
23 //! [`chain::Watch`]: ../trait.Watch.html
25 use bitcoin::blockdata::block::{Block, BlockHeader};
26 use bitcoin::blockdata::transaction::{TxOut,Transaction};
27 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
28 use bitcoin::blockdata::script::{Script, Builder};
29 use bitcoin::blockdata::opcodes;
31 use bitcoin::hashes::Hash;
32 use bitcoin::hashes::sha256::Hash as Sha256;
33 use bitcoin::hash_types::{Txid, BlockHash, WPubkeyHash};
35 use bitcoin::secp256k1::{Secp256k1,Signature};
36 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
37 use bitcoin::secp256k1;
39 use ln::msgs::DecodeError;
41 use ln::chan_utils::{CounterpartyCommitmentSecrets, HTLCOutputInCommitment, HTLCType, ChannelTransactionParameters, HolderCommitmentTransaction};
42 use ln::channelmanager::{HTLCSource, PaymentPreimage, PaymentHash};
43 use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
45 use chain::chaininterface::{BroadcasterInterface, FeeEstimator};
46 use chain::transaction::{OutPoint, TransactionData};
47 use chain::keysinterface::{SpendableOutputDescriptor, StaticPaymentOutputDescriptor, DelayedPaymentOutputDescriptor, Sign, KeysInterface};
49 use util::logger::Logger;
50 use util::ser::{Readable, ReadableArgs, MaybeReadable, Writer, Writeable, U48};
52 use util::events::Event;
54 use std::collections::{HashMap, HashSet, hash_map};
60 /// An update generated by the underlying Channel itself which contains some new information the
61 /// ChannelMonitor should be made aware of.
62 #[cfg_attr(any(test, feature = "fuzztarget", feature = "_test_utils"), derive(PartialEq))]
65 pub struct ChannelMonitorUpdate {
66 pub(crate) updates: Vec<ChannelMonitorUpdateStep>,
67 /// The sequence number of this update. Updates *must* be replayed in-order according to this
68 /// sequence number (and updates may panic if they are not). The update_id values are strictly
69 /// increasing and increase by one for each new update, with one exception specified below.
71 /// This sequence number is also used to track up to which points updates which returned
72 /// ChannelMonitorUpdateErr::TemporaryFailure have been applied to all copies of a given
73 /// ChannelMonitor when ChannelManager::channel_monitor_updated is called.
75 /// The only instance where update_id values are not strictly increasing is the case where we
76 /// allow post-force-close updates with a special update ID of [`CLOSED_CHANNEL_UPDATE_ID`]. See
77 /// its docs for more details.
79 /// [`CLOSED_CHANNEL_UPDATE_ID`]: constant.CLOSED_CHANNEL_UPDATE_ID.html
84 /// (1) a channel has been force closed and
85 /// (2) we receive a preimage from a forward link that allows us to spend an HTLC output on
86 /// this channel's (the backward link's) broadcasted commitment transaction
87 /// then we allow the `ChannelManager` to send a `ChannelMonitorUpdate` with this update ID,
88 /// with the update providing said payment preimage. No other update types are allowed after
90 pub const CLOSED_CHANNEL_UPDATE_ID: u64 = std::u64::MAX;
92 impl Writeable for ChannelMonitorUpdate {
93 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
94 self.update_id.write(w)?;
95 (self.updates.len() as u64).write(w)?;
96 for update_step in self.updates.iter() {
97 update_step.write(w)?;
102 impl Readable for ChannelMonitorUpdate {
103 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
104 let update_id: u64 = Readable::read(r)?;
105 let len: u64 = Readable::read(r)?;
106 let mut updates = Vec::with_capacity(cmp::min(len as usize, MAX_ALLOC_SIZE / ::std::mem::size_of::<ChannelMonitorUpdateStep>()));
108 updates.push(Readable::read(r)?);
110 Ok(Self { update_id, updates })
114 /// An error enum representing a failure to persist a channel monitor update.
115 #[derive(Clone, Debug)]
116 pub enum ChannelMonitorUpdateErr {
117 /// Used to indicate a temporary failure (eg connection to a watchtower or remote backup of
118 /// our state failed, but is expected to succeed at some point in the future).
120 /// Such a failure will "freeze" a channel, preventing us from revoking old states or
121 /// submitting new commitment transactions to the counterparty. Once the update(s) which failed
122 /// have been successfully applied, ChannelManager::channel_monitor_updated can be used to
123 /// restore the channel to an operational state.
125 /// Note that a given ChannelManager will *never* re-generate a given ChannelMonitorUpdate. If
126 /// you return a TemporaryFailure you must ensure that it is written to disk safely before
127 /// writing out the latest ChannelManager state.
129 /// Even when a channel has been "frozen" updates to the ChannelMonitor can continue to occur
130 /// (eg if an inbound HTLC which we forwarded was claimed upstream resulting in us attempting
131 /// to claim it on this channel) and those updates must be applied wherever they can be. At
132 /// least one such updated ChannelMonitor must be persisted otherwise PermanentFailure should
133 /// be returned to get things on-chain ASAP using only the in-memory copy. Obviously updates to
134 /// the channel which would invalidate previous ChannelMonitors are not made when a channel has
137 /// Note that even if updates made after TemporaryFailure succeed you must still call
138 /// channel_monitor_updated to ensure you have the latest monitor and re-enable normal channel
141 /// Note that the update being processed here will not be replayed for you when you call
142 /// ChannelManager::channel_monitor_updated, so you must store the update itself along
143 /// with the persisted ChannelMonitor on your own local disk prior to returning a
144 /// TemporaryFailure. You may, of course, employ a journaling approach, storing only the
145 /// ChannelMonitorUpdate on disk without updating the monitor itself, replaying the journal at
148 /// For deployments where a copy of ChannelMonitors and other local state are backed up in a
149 /// remote location (with local copies persisted immediately), it is anticipated that all
150 /// updates will return TemporaryFailure until the remote copies could be updated.
152 /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
153 /// different watchtower and cannot update with all watchtowers that were previously informed
154 /// of this channel).
156 /// At reception of this error, ChannelManager will force-close the channel and return at
157 /// least a final ChannelMonitorUpdate::ChannelForceClosed which must be delivered to at
158 /// least one ChannelMonitor copy. Revocation secret MUST NOT be released and offchain channel
159 /// update must be rejected.
161 /// This failure may also signal a failure to update the local persisted copy of one of
162 /// the channel monitor instance.
164 /// Note that even when you fail a holder commitment transaction update, you must store the
165 /// update to ensure you can claim from it in case of a duplicate copy of this ChannelMonitor
166 /// broadcasts it (e.g distributed channel-monitor deployment)
168 /// In case of distributed watchtowers deployment, the new version must be written to disk, as
169 /// state may have been stored but rejected due to a block forcing a commitment broadcast. This
170 /// storage is used to claim outputs of rejected state confirmed onchain by another watchtower,
171 /// lagging behind on block processing.
175 /// General Err type for ChannelMonitor actions. Generally, this implies that the data provided is
176 /// inconsistent with the ChannelMonitor being called. eg for ChannelMonitor::update_monitor this
177 /// means you tried to update a monitor for a different channel or the ChannelMonitorUpdate was
179 /// Contains a developer-readable error message.
180 #[derive(Clone, Debug)]
181 pub struct MonitorUpdateError(pub &'static str);
183 /// An event to be processed by the ChannelManager.
184 #[derive(Clone, PartialEq)]
185 pub enum MonitorEvent {
186 /// A monitor event containing an HTLCUpdate.
187 HTLCEvent(HTLCUpdate),
189 /// A monitor event that the Channel's commitment transaction was broadcasted.
190 CommitmentTxBroadcasted(OutPoint),
193 /// Simple structure sent back by `chain::Watch` when an HTLC from a forward channel is detected on
194 /// chain. Used to update the corresponding HTLC in the backward channel. Failing to pass the
195 /// preimage claim backward will lead to loss of funds.
197 /// [`chain::Watch`]: ../trait.Watch.html
198 #[derive(Clone, PartialEq)]
199 pub struct HTLCUpdate {
200 pub(crate) payment_hash: PaymentHash,
201 pub(crate) payment_preimage: Option<PaymentPreimage>,
202 pub(crate) source: HTLCSource
204 impl_writeable!(HTLCUpdate, 0, { payment_hash, payment_preimage, source });
206 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
207 /// instead claiming it in its own individual transaction.
208 pub(crate) const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
209 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
210 /// HTLC-Success transaction.
211 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
212 /// transaction confirmed (and we use it in a few more, equivalent, places).
213 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 6;
214 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
215 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
216 /// copies of ChannelMonitors, including watchtowers). We could enforce the contract by failing
217 /// at CLTV expiration height but giving a grace period to our peer may be profitable for us if he
218 /// can provide an over-late preimage. Nevertheless, grace period has to be accounted in our
219 /// CLTV_EXPIRY_DELTA to be secure. Following this policy we may decrease the rate of channel failures
220 /// due to expiration but increase the cost of funds being locked longuer in case of failure.
221 /// This delay also cover a low-power peer being slow to process blocks and so being behind us on
222 /// accurate block height.
223 /// In case of onchain failure to be pass backward we may see the last block of ANTI_REORG_DELAY
224 /// with at worst this delay, so we are not only using this value as a mercy for them but also
225 /// us as a safeguard to delay with enough time.
226 pub(crate) const LATENCY_GRACE_PERIOD_BLOCKS: u32 = 3;
227 /// Number of blocks we wait on seeing a HTLC output being solved before we fail corresponding inbound
228 /// HTLCs. This prevents us from failing backwards and then getting a reorg resulting in us losing money.
229 /// We use also this delay to be sure we can remove our in-flight claim txn from bump candidates buffer.
230 /// It may cause spurrious generation of bumped claim txn but that's allright given the outpoint is already
231 /// solved by a previous claim tx. What we want to avoid is reorg evicting our claim tx and us not
232 /// keeping bumping another claim tx to solve the outpoint.
233 pub(crate) const ANTI_REORG_DELAY: u32 = 6;
234 /// Number of blocks before confirmation at which we fail back an un-relayed HTLC or at which we
235 /// refuse to accept a new HTLC.
237 /// This is used for a few separate purposes:
238 /// 1) if we've received an MPP HTLC to us and it expires within this many blocks and we are
239 /// waiting on additional parts (or waiting on the preimage for any HTLC from the user), we will
241 /// 2) if we receive an HTLC within this many blocks of its expiry (plus one to avoid a race
242 /// condition with the above), we will fail this HTLC without telling the user we received it,
243 /// 3) if we are waiting on a connection or a channel state update to send an HTLC to a peer, and
244 /// that HTLC expires within this many blocks, we will simply fail the HTLC instead.
246 /// (1) is all about protecting us - we need enough time to update the channel state before we hit
247 /// CLTV_CLAIM_BUFFER, at which point we'd go on chain to claim the HTLC with the preimage.
249 /// (2) is the same, but with an additional buffer to avoid accepting an HTLC which is immediately
250 /// in a race condition between the user connecting a block (which would fail it) and the user
251 /// providing us the preimage (which would claim it).
253 /// (3) is about our counterparty - we don't want to relay an HTLC to a counterparty when they may
254 /// end up force-closing the channel on us to claim it.
255 pub(crate) const HTLC_FAIL_BACK_BUFFER: u32 = CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS;
257 // TODO(devrandom) replace this with HolderCommitmentTransaction
258 #[derive(Clone, PartialEq)]
259 struct HolderSignedTx {
260 /// txid of the transaction in tx, just used to make comparison faster
262 revocation_key: PublicKey,
263 a_htlc_key: PublicKey,
264 b_htlc_key: PublicKey,
265 delayed_payment_key: PublicKey,
266 per_commitment_point: PublicKey,
268 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
271 /// We use this to track counterparty commitment transactions and htlcs outputs and
272 /// use it to generate any justice or 2nd-stage preimage/timeout transactions.
274 struct CounterpartyCommitmentTransaction {
275 counterparty_delayed_payment_base_key: PublicKey,
276 counterparty_htlc_base_key: PublicKey,
277 on_counterparty_tx_csv: u16,
278 per_htlc: HashMap<Txid, Vec<HTLCOutputInCommitment>>
281 impl Writeable for CounterpartyCommitmentTransaction {
282 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
283 self.counterparty_delayed_payment_base_key.write(w)?;
284 self.counterparty_htlc_base_key.write(w)?;
285 w.write_all(&byte_utils::be16_to_array(self.on_counterparty_tx_csv))?;
286 w.write_all(&byte_utils::be64_to_array(self.per_htlc.len() as u64))?;
287 for (ref txid, ref htlcs) in self.per_htlc.iter() {
288 w.write_all(&txid[..])?;
289 w.write_all(&byte_utils::be64_to_array(htlcs.len() as u64))?;
290 for &ref htlc in htlcs.iter() {
297 impl Readable for CounterpartyCommitmentTransaction {
298 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
299 let counterparty_commitment_transaction = {
300 let counterparty_delayed_payment_base_key = Readable::read(r)?;
301 let counterparty_htlc_base_key = Readable::read(r)?;
302 let on_counterparty_tx_csv: u16 = Readable::read(r)?;
303 let per_htlc_len: u64 = Readable::read(r)?;
304 let mut per_htlc = HashMap::with_capacity(cmp::min(per_htlc_len as usize, MAX_ALLOC_SIZE / 64));
305 for _ in 0..per_htlc_len {
306 let txid: Txid = Readable::read(r)?;
307 let htlcs_count: u64 = Readable::read(r)?;
308 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
309 for _ in 0..htlcs_count {
310 let htlc = Readable::read(r)?;
313 if let Some(_) = per_htlc.insert(txid, htlcs) {
314 return Err(DecodeError::InvalidValue);
317 CounterpartyCommitmentTransaction {
318 counterparty_delayed_payment_base_key,
319 counterparty_htlc_base_key,
320 on_counterparty_tx_csv,
324 Ok(counterparty_commitment_transaction)
328 /// When ChannelMonitor discovers an onchain outpoint being a step of a channel and that it needs
329 /// to generate a tx to push channel state forward, we cache outpoint-solving tx material to build
330 /// a new bumped one in case of lenghty confirmation delay
331 #[derive(Clone, PartialEq)]
332 pub(crate) enum InputMaterial {
334 per_commitment_point: PublicKey,
335 counterparty_delayed_payment_base_key: PublicKey,
336 counterparty_htlc_base_key: PublicKey,
337 per_commitment_key: SecretKey,
338 input_descriptor: InputDescriptors,
340 htlc: Option<HTLCOutputInCommitment>,
341 on_counterparty_tx_csv: u16,
344 per_commitment_point: PublicKey,
345 counterparty_delayed_payment_base_key: PublicKey,
346 counterparty_htlc_base_key: PublicKey,
347 preimage: Option<PaymentPreimage>,
348 htlc: HTLCOutputInCommitment
351 preimage: Option<PaymentPreimage>,
355 funding_redeemscript: Script,
359 impl Writeable for InputMaterial {
360 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
362 &InputMaterial::Revoked { ref per_commitment_point, ref counterparty_delayed_payment_base_key, ref counterparty_htlc_base_key, ref per_commitment_key, ref input_descriptor, ref amount, ref htlc, ref on_counterparty_tx_csv} => {
363 writer.write_all(&[0; 1])?;
364 per_commitment_point.write(writer)?;
365 counterparty_delayed_payment_base_key.write(writer)?;
366 counterparty_htlc_base_key.write(writer)?;
367 writer.write_all(&per_commitment_key[..])?;
368 input_descriptor.write(writer)?;
369 writer.write_all(&byte_utils::be64_to_array(*amount))?;
371 on_counterparty_tx_csv.write(writer)?;
373 &InputMaterial::CounterpartyHTLC { ref per_commitment_point, ref counterparty_delayed_payment_base_key, ref counterparty_htlc_base_key, ref preimage, ref htlc} => {
374 writer.write_all(&[1; 1])?;
375 per_commitment_point.write(writer)?;
376 counterparty_delayed_payment_base_key.write(writer)?;
377 counterparty_htlc_base_key.write(writer)?;
378 preimage.write(writer)?;
381 &InputMaterial::HolderHTLC { ref preimage, ref amount } => {
382 writer.write_all(&[2; 1])?;
383 preimage.write(writer)?;
384 writer.write_all(&byte_utils::be64_to_array(*amount))?;
386 &InputMaterial::Funding { ref funding_redeemscript } => {
387 writer.write_all(&[3; 1])?;
388 funding_redeemscript.write(writer)?;
395 impl Readable for InputMaterial {
396 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
397 let input_material = match <u8 as Readable>::read(reader)? {
399 let per_commitment_point = Readable::read(reader)?;
400 let counterparty_delayed_payment_base_key = Readable::read(reader)?;
401 let counterparty_htlc_base_key = Readable::read(reader)?;
402 let per_commitment_key = Readable::read(reader)?;
403 let input_descriptor = Readable::read(reader)?;
404 let amount = Readable::read(reader)?;
405 let htlc = Readable::read(reader)?;
406 let on_counterparty_tx_csv = Readable::read(reader)?;
407 InputMaterial::Revoked {
408 per_commitment_point,
409 counterparty_delayed_payment_base_key,
410 counterparty_htlc_base_key,
415 on_counterparty_tx_csv
419 let per_commitment_point = Readable::read(reader)?;
420 let counterparty_delayed_payment_base_key = Readable::read(reader)?;
421 let counterparty_htlc_base_key = Readable::read(reader)?;
422 let preimage = Readable::read(reader)?;
423 let htlc = Readable::read(reader)?;
424 InputMaterial::CounterpartyHTLC {
425 per_commitment_point,
426 counterparty_delayed_payment_base_key,
427 counterparty_htlc_base_key,
433 let preimage = Readable::read(reader)?;
434 let amount = Readable::read(reader)?;
435 InputMaterial::HolderHTLC {
441 InputMaterial::Funding {
442 funding_redeemscript: Readable::read(reader)?,
445 _ => return Err(DecodeError::InvalidValue),
451 /// ClaimRequest is a descriptor structure to communicate between detection
452 /// and reaction module. They are generated by ChannelMonitor while parsing
453 /// onchain txn leaked from a channel and handed over to OnchainTxHandler which
454 /// is responsible for opportunistic aggregation, selecting and enforcing
455 /// bumping logic, building and signing transactions.
456 pub(crate) struct ClaimRequest {
457 // Block height before which claiming is exclusive to one party,
458 // after reaching it, claiming may be contentious.
459 pub(crate) absolute_timelock: u32,
460 // Timeout tx must have nLocktime set which means aggregating multiple
461 // ones must take the higher nLocktime among them to satisfy all of them.
462 // Sadly it has few pitfalls, a) it takes longuer to get fund back b) CLTV_DELTA
463 // of a sooner-HTLC could be swallowed by the highest nLocktime of the HTLC set.
464 // Do simplify we mark them as non-aggregable.
465 pub(crate) aggregable: bool,
466 // Basic bitcoin outpoint (txid, vout)
467 pub(crate) outpoint: BitcoinOutPoint,
468 // Following outpoint type, set of data needed to generate transaction digest
469 // and satisfy witness program.
470 pub(crate) witness_data: InputMaterial
473 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
474 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
475 #[derive(Clone, PartialEq)]
477 /// HTLC output getting solved by a timeout, at maturation we pass upstream payment source information to solve
478 /// inbound HTLC in backward channel. Note, in case of preimage, we pass info to upstream without delay as we can
479 /// only win from it, so it's never an OnchainEvent
481 htlc_update: (HTLCSource, PaymentHash),
484 descriptor: SpendableOutputDescriptor,
488 const SERIALIZATION_VERSION: u8 = 1;
489 const MIN_SERIALIZATION_VERSION: u8 = 1;
491 #[cfg_attr(any(test, feature = "fuzztarget", feature = "_test_utils"), derive(PartialEq))]
493 pub(crate) enum ChannelMonitorUpdateStep {
494 LatestHolderCommitmentTXInfo {
495 commitment_tx: HolderCommitmentTransaction,
496 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
498 LatestCounterpartyCommitmentTXInfo {
499 commitment_txid: Txid,
500 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
501 commitment_number: u64,
502 their_revocation_point: PublicKey,
505 payment_preimage: PaymentPreimage,
511 /// Used to indicate that the no future updates will occur, and likely that the latest holder
512 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
514 /// If set to false, we shouldn't broadcast the latest holder commitment transaction as we
515 /// think we've fallen behind!
516 should_broadcast: bool,
520 impl Writeable for ChannelMonitorUpdateStep {
521 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
523 &ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { ref commitment_tx, ref htlc_outputs } => {
525 commitment_tx.write(w)?;
526 (htlc_outputs.len() as u64).write(w)?;
527 for &(ref output, ref signature, ref source) in htlc_outputs.iter() {
533 &ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { commitment_txid, ref htlc_outputs, ref commitment_number, ref their_revocation_point } => {
535 commitment_txid.write(w)?;
536 commitment_number.write(w)?;
537 their_revocation_point.write(w)?;
538 (htlc_outputs.len() as u64).write(w)?;
539 for &(ref output, ref source) in htlc_outputs.iter() {
541 source.as_ref().map(|b| b.as_ref()).write(w)?;
544 &ChannelMonitorUpdateStep::PaymentPreimage { ref payment_preimage } => {
546 payment_preimage.write(w)?;
548 &ChannelMonitorUpdateStep::CommitmentSecret { ref idx, ref secret } => {
553 &ChannelMonitorUpdateStep::ChannelForceClosed { ref should_broadcast } => {
555 should_broadcast.write(w)?;
561 impl Readable for ChannelMonitorUpdateStep {
562 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
563 match Readable::read(r)? {
565 Ok(ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo {
566 commitment_tx: Readable::read(r)?,
568 let len: u64 = Readable::read(r)?;
569 let mut res = Vec::new();
571 res.push((Readable::read(r)?, Readable::read(r)?, Readable::read(r)?));
578 Ok(ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo {
579 commitment_txid: Readable::read(r)?,
580 commitment_number: Readable::read(r)?,
581 their_revocation_point: Readable::read(r)?,
583 let len: u64 = Readable::read(r)?;
584 let mut res = Vec::new();
586 res.push((Readable::read(r)?, <Option<HTLCSource> as Readable>::read(r)?.map(|o| Box::new(o))));
593 Ok(ChannelMonitorUpdateStep::PaymentPreimage {
594 payment_preimage: Readable::read(r)?,
598 Ok(ChannelMonitorUpdateStep::CommitmentSecret {
599 idx: Readable::read(r)?,
600 secret: Readable::read(r)?,
604 Ok(ChannelMonitorUpdateStep::ChannelForceClosed {
605 should_broadcast: Readable::read(r)?
608 _ => Err(DecodeError::InvalidValue),
613 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
614 /// on-chain transactions to ensure no loss of funds occurs.
616 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
617 /// information and are actively monitoring the chain.
619 /// Pending Events or updated HTLCs which have not yet been read out by
620 /// get_and_clear_pending_monitor_events or get_and_clear_pending_events are serialized to disk and
621 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
622 /// gotten are fully handled before re-serializing the new state.
624 /// Note that the deserializer is only implemented for (BlockHash, ChannelMonitor), which
625 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
626 /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
627 /// returned block hash and the the current chain and then reconnecting blocks to get to the
628 /// best chain) upon deserializing the object!
629 pub struct ChannelMonitor<Signer: Sign> {
631 pub(crate) inner: Mutex<ChannelMonitorImpl<Signer>>,
633 inner: Mutex<ChannelMonitorImpl<Signer>>,
636 pub(crate) struct ChannelMonitorImpl<Signer: Sign> {
637 latest_update_id: u64,
638 commitment_transaction_number_obscure_factor: u64,
640 destination_script: Script,
641 broadcasted_holder_revokable_script: Option<(Script, PublicKey, PublicKey)>,
642 counterparty_payment_script: Script,
643 shutdown_script: Script,
645 channel_keys_id: [u8; 32],
646 holder_revocation_basepoint: PublicKey,
647 funding_info: (OutPoint, Script),
648 current_counterparty_commitment_txid: Option<Txid>,
649 prev_counterparty_commitment_txid: Option<Txid>,
651 counterparty_tx_cache: CounterpartyCommitmentTransaction,
652 funding_redeemscript: Script,
653 channel_value_satoshis: u64,
654 // first is the idx of the first of the two revocation points
655 their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
657 on_holder_tx_csv: u16,
659 commitment_secrets: CounterpartyCommitmentSecrets,
660 counterparty_claimable_outpoints: HashMap<Txid, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
661 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
662 /// Nor can we figure out their commitment numbers without the commitment transaction they are
663 /// spending. Thus, in order to claim them via revocation key, we track all the counterparty
664 /// commitment transactions which we find on-chain, mapping them to the commitment number which
665 /// can be used to derive the revocation key and claim the transactions.
666 counterparty_commitment_txn_on_chain: HashMap<Txid, u64>,
667 /// Cache used to make pruning of payment_preimages faster.
668 /// Maps payment_hash values to commitment numbers for counterparty transactions for non-revoked
669 /// counterparty transactions (ie should remain pretty small).
670 /// Serialized to disk but should generally not be sent to Watchtowers.
671 counterparty_hash_commitment_number: HashMap<PaymentHash, u64>,
673 // We store two holder commitment transactions to avoid any race conditions where we may update
674 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
675 // various monitors for one channel being out of sync, and us broadcasting a holder
676 // transaction for which we have deleted claim information on some watchtowers.
677 prev_holder_signed_commitment_tx: Option<HolderSignedTx>,
678 current_holder_commitment_tx: HolderSignedTx,
680 // Used just for ChannelManager to make sure it has the latest channel data during
682 current_counterparty_commitment_number: u64,
683 // Used just for ChannelManager to make sure it has the latest channel data during
685 current_holder_commitment_number: u64,
687 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
689 pending_monitor_events: Vec<MonitorEvent>,
690 pending_events: Vec<Event>,
692 // Used to track onchain events, i.e transactions parts of channels confirmed on chain, on which
693 // we have to take actions once they reach enough confs. Key is a block height timer, i.e we enforce
694 // actions when we receive a block with given height. Actions depend on OnchainEvent type.
695 onchain_events_waiting_threshold_conf: HashMap<u32, Vec<OnchainEvent>>,
697 // If we get serialized out and re-read, we need to make sure that the chain monitoring
698 // interface knows about the TXOs that we want to be notified of spends of. We could probably
699 // be smart and derive them from the above storage fields, but its much simpler and more
700 // Obviously Correct (tm) if we just keep track of them explicitly.
701 outputs_to_watch: HashMap<Txid, Vec<(u32, Script)>>,
704 pub onchain_tx_handler: OnchainTxHandler<Signer>,
706 onchain_tx_handler: OnchainTxHandler<Signer>,
708 // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
709 // channel has been force-closed. After this is set, no further holder commitment transaction
710 // updates may occur, and we panic!() if one is provided.
711 lockdown_from_offchain: bool,
713 // Set once we've signed a holder commitment transaction and handed it over to our
714 // OnchainTxHandler. After this is set, no future updates to our holder commitment transactions
715 // may occur, and we fail any such monitor updates.
717 // In case of update rejection due to a locally already signed commitment transaction, we
718 // nevertheless store update content to track in case of concurrent broadcast by another
719 // remote monitor out-of-order with regards to the block view.
720 holder_tx_signed: bool,
722 // We simply modify last_block_hash in Channel's block_connected so that serialization is
723 // consistent but hopefully the users' copy handles block_connected in a consistent way.
724 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
725 // their last_block_hash from its state and not based on updated copies that didn't run through
726 // the full block_connected).
727 last_block_hash: BlockHash,
728 secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
731 #[cfg(any(test, feature = "fuzztarget", feature = "_test_utils"))]
732 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
733 /// underlying object
734 impl<Signer: Sign> PartialEq for ChannelMonitor<Signer> {
735 fn eq(&self, other: &Self) -> bool {
736 let inner = self.inner.lock().unwrap();
737 let other = other.inner.lock().unwrap();
742 #[cfg(any(test, feature = "fuzztarget", feature = "_test_utils"))]
743 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
744 /// underlying object
745 impl<Signer: Sign> PartialEq for ChannelMonitorImpl<Signer> {
746 fn eq(&self, other: &Self) -> bool {
747 if self.latest_update_id != other.latest_update_id ||
748 self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
749 self.destination_script != other.destination_script ||
750 self.broadcasted_holder_revokable_script != other.broadcasted_holder_revokable_script ||
751 self.counterparty_payment_script != other.counterparty_payment_script ||
752 self.channel_keys_id != other.channel_keys_id ||
753 self.holder_revocation_basepoint != other.holder_revocation_basepoint ||
754 self.funding_info != other.funding_info ||
755 self.current_counterparty_commitment_txid != other.current_counterparty_commitment_txid ||
756 self.prev_counterparty_commitment_txid != other.prev_counterparty_commitment_txid ||
757 self.counterparty_tx_cache != other.counterparty_tx_cache ||
758 self.funding_redeemscript != other.funding_redeemscript ||
759 self.channel_value_satoshis != other.channel_value_satoshis ||
760 self.their_cur_revocation_points != other.their_cur_revocation_points ||
761 self.on_holder_tx_csv != other.on_holder_tx_csv ||
762 self.commitment_secrets != other.commitment_secrets ||
763 self.counterparty_claimable_outpoints != other.counterparty_claimable_outpoints ||
764 self.counterparty_commitment_txn_on_chain != other.counterparty_commitment_txn_on_chain ||
765 self.counterparty_hash_commitment_number != other.counterparty_hash_commitment_number ||
766 self.prev_holder_signed_commitment_tx != other.prev_holder_signed_commitment_tx ||
767 self.current_counterparty_commitment_number != other.current_counterparty_commitment_number ||
768 self.current_holder_commitment_number != other.current_holder_commitment_number ||
769 self.current_holder_commitment_tx != other.current_holder_commitment_tx ||
770 self.payment_preimages != other.payment_preimages ||
771 self.pending_monitor_events != other.pending_monitor_events ||
772 self.pending_events.len() != other.pending_events.len() || // We trust events to round-trip properly
773 self.onchain_events_waiting_threshold_conf != other.onchain_events_waiting_threshold_conf ||
774 self.outputs_to_watch != other.outputs_to_watch ||
775 self.lockdown_from_offchain != other.lockdown_from_offchain ||
776 self.holder_tx_signed != other.holder_tx_signed
785 impl<Signer: Sign> Writeable for ChannelMonitor<Signer> {
786 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
787 //TODO: We still write out all the serialization here manually instead of using the fancy
788 //serialization framework we have, we should migrate things over to it.
789 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
790 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
792 self.inner.lock().unwrap().write(writer)
796 impl<Signer: Sign> Writeable for ChannelMonitorImpl<Signer> {
797 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
798 self.latest_update_id.write(writer)?;
800 // Set in initial Channel-object creation, so should always be set by now:
801 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
803 self.destination_script.write(writer)?;
804 if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
805 writer.write_all(&[0; 1])?;
806 broadcasted_holder_revokable_script.0.write(writer)?;
807 broadcasted_holder_revokable_script.1.write(writer)?;
808 broadcasted_holder_revokable_script.2.write(writer)?;
810 writer.write_all(&[1; 1])?;
813 self.counterparty_payment_script.write(writer)?;
814 self.shutdown_script.write(writer)?;
816 self.channel_keys_id.write(writer)?;
817 self.holder_revocation_basepoint.write(writer)?;
818 writer.write_all(&self.funding_info.0.txid[..])?;
819 writer.write_all(&byte_utils::be16_to_array(self.funding_info.0.index))?;
820 self.funding_info.1.write(writer)?;
821 self.current_counterparty_commitment_txid.write(writer)?;
822 self.prev_counterparty_commitment_txid.write(writer)?;
824 self.counterparty_tx_cache.write(writer)?;
825 self.funding_redeemscript.write(writer)?;
826 self.channel_value_satoshis.write(writer)?;
828 match self.their_cur_revocation_points {
829 Some((idx, pubkey, second_option)) => {
830 writer.write_all(&byte_utils::be48_to_array(idx))?;
831 writer.write_all(&pubkey.serialize())?;
832 match second_option {
833 Some(second_pubkey) => {
834 writer.write_all(&second_pubkey.serialize())?;
837 writer.write_all(&[0; 33])?;
842 writer.write_all(&byte_utils::be48_to_array(0))?;
846 writer.write_all(&byte_utils::be16_to_array(self.on_holder_tx_csv))?;
848 self.commitment_secrets.write(writer)?;
850 macro_rules! serialize_htlc_in_commitment {
851 ($htlc_output: expr) => {
852 writer.write_all(&[$htlc_output.offered as u8; 1])?;
853 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
854 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
855 writer.write_all(&$htlc_output.payment_hash.0[..])?;
856 $htlc_output.transaction_output_index.write(writer)?;
860 writer.write_all(&byte_utils::be64_to_array(self.counterparty_claimable_outpoints.len() as u64))?;
861 for (ref txid, ref htlc_infos) in self.counterparty_claimable_outpoints.iter() {
862 writer.write_all(&txid[..])?;
863 writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
864 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
865 serialize_htlc_in_commitment!(htlc_output);
866 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
870 writer.write_all(&byte_utils::be64_to_array(self.counterparty_commitment_txn_on_chain.len() as u64))?;
871 for (ref txid, commitment_number) in self.counterparty_commitment_txn_on_chain.iter() {
872 writer.write_all(&txid[..])?;
873 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
876 writer.write_all(&byte_utils::be64_to_array(self.counterparty_hash_commitment_number.len() as u64))?;
877 for (ref payment_hash, commitment_number) in self.counterparty_hash_commitment_number.iter() {
878 writer.write_all(&payment_hash.0[..])?;
879 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
882 macro_rules! serialize_holder_tx {
883 ($holder_tx: expr) => {
884 $holder_tx.txid.write(writer)?;
885 writer.write_all(&$holder_tx.revocation_key.serialize())?;
886 writer.write_all(&$holder_tx.a_htlc_key.serialize())?;
887 writer.write_all(&$holder_tx.b_htlc_key.serialize())?;
888 writer.write_all(&$holder_tx.delayed_payment_key.serialize())?;
889 writer.write_all(&$holder_tx.per_commitment_point.serialize())?;
891 writer.write_all(&byte_utils::be32_to_array($holder_tx.feerate_per_kw))?;
892 writer.write_all(&byte_utils::be64_to_array($holder_tx.htlc_outputs.len() as u64))?;
893 for &(ref htlc_output, ref sig, ref htlc_source) in $holder_tx.htlc_outputs.iter() {
894 serialize_htlc_in_commitment!(htlc_output);
895 if let &Some(ref their_sig) = sig {
897 writer.write_all(&their_sig.serialize_compact())?;
901 htlc_source.write(writer)?;
906 if let Some(ref prev_holder_tx) = self.prev_holder_signed_commitment_tx {
907 writer.write_all(&[1; 1])?;
908 serialize_holder_tx!(prev_holder_tx);
910 writer.write_all(&[0; 1])?;
913 serialize_holder_tx!(self.current_holder_commitment_tx);
915 writer.write_all(&byte_utils::be48_to_array(self.current_counterparty_commitment_number))?;
916 writer.write_all(&byte_utils::be48_to_array(self.current_holder_commitment_number))?;
918 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
919 for payment_preimage in self.payment_preimages.values() {
920 writer.write_all(&payment_preimage.0[..])?;
923 writer.write_all(&byte_utils::be64_to_array(self.pending_monitor_events.len() as u64))?;
924 for event in self.pending_monitor_events.iter() {
926 MonitorEvent::HTLCEvent(upd) => {
930 MonitorEvent::CommitmentTxBroadcasted(_) => 1u8.write(writer)?
934 writer.write_all(&byte_utils::be64_to_array(self.pending_events.len() as u64))?;
935 for event in self.pending_events.iter() {
936 event.write(writer)?;
939 self.last_block_hash.write(writer)?;
941 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_waiting_threshold_conf.len() as u64))?;
942 for (ref target, ref events) in self.onchain_events_waiting_threshold_conf.iter() {
943 writer.write_all(&byte_utils::be32_to_array(**target))?;
944 writer.write_all(&byte_utils::be64_to_array(events.len() as u64))?;
945 for ev in events.iter() {
947 OnchainEvent::HTLCUpdate { ref htlc_update } => {
949 htlc_update.0.write(writer)?;
950 htlc_update.1.write(writer)?;
952 OnchainEvent::MaturingOutput { ref descriptor } => {
954 descriptor.write(writer)?;
960 (self.outputs_to_watch.len() as u64).write(writer)?;
961 for (txid, idx_scripts) in self.outputs_to_watch.iter() {
963 (idx_scripts.len() as u64).write(writer)?;
964 for (idx, script) in idx_scripts.iter() {
966 script.write(writer)?;
969 self.onchain_tx_handler.write(writer)?;
971 self.lockdown_from_offchain.write(writer)?;
972 self.holder_tx_signed.write(writer)?;
978 impl<Signer: Sign> ChannelMonitor<Signer> {
979 pub(crate) fn new(secp_ctx: Secp256k1<secp256k1::All>, keys: Signer, shutdown_pubkey: &PublicKey,
980 on_counterparty_tx_csv: u16, destination_script: &Script, funding_info: (OutPoint, Script),
981 channel_parameters: &ChannelTransactionParameters,
982 funding_redeemscript: Script, channel_value_satoshis: u64,
983 commitment_transaction_number_obscure_factor: u64,
984 initial_holder_commitment_tx: HolderCommitmentTransaction,
985 last_block_hash: BlockHash) -> ChannelMonitor<Signer> {
987 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
988 let our_channel_close_key_hash = WPubkeyHash::hash(&shutdown_pubkey.serialize());
989 let shutdown_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
990 let payment_key_hash = WPubkeyHash::hash(&keys.pubkeys().payment_point.serialize());
991 let counterparty_payment_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_key_hash[..]).into_script();
993 let counterparty_channel_parameters = channel_parameters.counterparty_parameters.as_ref().unwrap();
994 let counterparty_delayed_payment_base_key = counterparty_channel_parameters.pubkeys.delayed_payment_basepoint;
995 let counterparty_htlc_base_key = counterparty_channel_parameters.pubkeys.htlc_basepoint;
996 let counterparty_tx_cache = CounterpartyCommitmentTransaction { counterparty_delayed_payment_base_key, counterparty_htlc_base_key, on_counterparty_tx_csv, per_htlc: HashMap::new() };
998 let channel_keys_id = keys.channel_keys_id();
999 let holder_revocation_basepoint = keys.pubkeys().revocation_basepoint;
1001 // block for Rust 1.34 compat
1002 let (holder_commitment_tx, current_holder_commitment_number) = {
1003 let trusted_tx = initial_holder_commitment_tx.trust();
1004 let txid = trusted_tx.txid();
1006 let tx_keys = trusted_tx.keys();
1007 let holder_commitment_tx = HolderSignedTx {
1009 revocation_key: tx_keys.revocation_key,
1010 a_htlc_key: tx_keys.broadcaster_htlc_key,
1011 b_htlc_key: tx_keys.countersignatory_htlc_key,
1012 delayed_payment_key: tx_keys.broadcaster_delayed_payment_key,
1013 per_commitment_point: tx_keys.per_commitment_point,
1014 feerate_per_kw: trusted_tx.feerate_per_kw(),
1015 htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
1017 (holder_commitment_tx, trusted_tx.commitment_number())
1020 let onchain_tx_handler =
1021 OnchainTxHandler::new(destination_script.clone(), keys,
1022 channel_parameters.clone(), initial_holder_commitment_tx, secp_ctx.clone());
1024 let mut outputs_to_watch = HashMap::new();
1025 outputs_to_watch.insert(funding_info.0.txid, vec![(funding_info.0.index as u32, funding_info.1.clone())]);
1028 inner: Mutex::new(ChannelMonitorImpl {
1029 latest_update_id: 0,
1030 commitment_transaction_number_obscure_factor,
1032 destination_script: destination_script.clone(),
1033 broadcasted_holder_revokable_script: None,
1034 counterparty_payment_script,
1038 holder_revocation_basepoint,
1040 current_counterparty_commitment_txid: None,
1041 prev_counterparty_commitment_txid: None,
1043 counterparty_tx_cache,
1044 funding_redeemscript,
1045 channel_value_satoshis,
1046 their_cur_revocation_points: None,
1048 on_holder_tx_csv: counterparty_channel_parameters.selected_contest_delay,
1050 commitment_secrets: CounterpartyCommitmentSecrets::new(),
1051 counterparty_claimable_outpoints: HashMap::new(),
1052 counterparty_commitment_txn_on_chain: HashMap::new(),
1053 counterparty_hash_commitment_number: HashMap::new(),
1055 prev_holder_signed_commitment_tx: None,
1056 current_holder_commitment_tx: holder_commitment_tx,
1057 current_counterparty_commitment_number: 1 << 48,
1058 current_holder_commitment_number,
1060 payment_preimages: HashMap::new(),
1061 pending_monitor_events: Vec::new(),
1062 pending_events: Vec::new(),
1064 onchain_events_waiting_threshold_conf: HashMap::new(),
1069 lockdown_from_offchain: false,
1070 holder_tx_signed: false,
1079 fn provide_secret(&self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
1080 self.inner.lock().unwrap().provide_secret(idx, secret)
1083 /// Informs this monitor of the latest counterparty (ie non-broadcastable) commitment transaction.
1084 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
1085 /// possibly future revocation/preimage information) to claim outputs where possible.
1086 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
1087 pub(crate) fn provide_latest_counterparty_commitment_tx<L: Deref>(
1090 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
1091 commitment_number: u64,
1092 their_revocation_point: PublicKey,
1094 ) where L::Target: Logger {
1095 self.inner.lock().unwrap().provide_latest_counterparty_commitment_tx(
1096 txid, htlc_outputs, commitment_number, their_revocation_point, logger)
1100 fn provide_latest_holder_commitment_tx(
1102 holder_commitment_tx: HolderCommitmentTransaction,
1103 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
1104 ) -> Result<(), MonitorUpdateError> {
1105 self.inner.lock().unwrap().provide_latest_holder_commitment_tx(
1106 holder_commitment_tx, htlc_outputs)
1110 pub(crate) fn provide_payment_preimage<B: Deref, F: Deref, L: Deref>(
1112 payment_hash: &PaymentHash,
1113 payment_preimage: &PaymentPreimage,
1118 B::Target: BroadcasterInterface,
1119 F::Target: FeeEstimator,
1122 self.inner.lock().unwrap().provide_payment_preimage(
1123 payment_hash, payment_preimage, broadcaster, fee_estimator, logger)
1126 pub(crate) fn broadcast_latest_holder_commitment_txn<B: Deref, L: Deref>(
1131 B::Target: BroadcasterInterface,
1134 self.inner.lock().unwrap().broadcast_latest_holder_commitment_txn(broadcaster, logger)
1137 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
1140 /// panics if the given update is not the next update by update_id.
1141 pub fn update_monitor<B: Deref, F: Deref, L: Deref>(
1143 updates: &ChannelMonitorUpdate,
1147 ) -> Result<(), MonitorUpdateError>
1149 B::Target: BroadcasterInterface,
1150 F::Target: FeeEstimator,
1153 self.inner.lock().unwrap().update_monitor(updates, broadcaster, fee_estimator, logger)
1156 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
1158 pub fn get_latest_update_id(&self) -> u64 {
1159 self.inner.lock().unwrap().get_latest_update_id()
1162 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
1163 pub fn get_funding_txo(&self) -> (OutPoint, Script) {
1164 self.inner.lock().unwrap().get_funding_txo().clone()
1167 /// Gets a list of txids, with their output scripts (in the order they appear in the
1168 /// transaction), which we must learn about spends of via block_connected().
1169 pub fn get_outputs_to_watch(&self) -> Vec<(Txid, Vec<(u32, Script)>)> {
1170 self.inner.lock().unwrap().get_outputs_to_watch()
1171 .iter().map(|(txid, outputs)| (*txid, outputs.clone())).collect()
1174 /// Loads the funding txo and outputs to watch into the given `chain::Filter` by repeatedly
1175 /// calling `chain::Filter::register_output` and `chain::Filter::register_tx` until all outputs
1176 /// have been registered.
1177 pub fn load_outputs_to_watch<F: Deref>(&self, filter: &F) where F::Target: chain::Filter {
1178 let lock = self.inner.lock().unwrap();
1179 filter.register_tx(&lock.get_funding_txo().0.txid, &lock.get_funding_txo().1);
1180 for (txid, outputs) in lock.get_outputs_to_watch().iter() {
1181 for (index, script_pubkey) in outputs.iter() {
1182 assert!(*index <= u16::max_value() as u32);
1183 filter.register_output(&OutPoint { txid: *txid, index: *index as u16 }, script_pubkey);
1188 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1189 /// ChannelManager via [`chain::Watch::release_pending_monitor_events`].
1191 /// [`chain::Watch::release_pending_monitor_events`]: ../trait.Watch.html#tymethod.release_pending_monitor_events
1192 pub fn get_and_clear_pending_monitor_events(&self) -> Vec<MonitorEvent> {
1193 self.inner.lock().unwrap().get_and_clear_pending_monitor_events()
1196 /// Gets the list of pending events which were generated by previous actions, clearing the list
1199 /// This is called by ChainMonitor::get_and_clear_pending_events() and is equivalent to
1200 /// EventsProvider::get_and_clear_pending_events() except that it requires &mut self as we do
1201 /// no internal locking in ChannelMonitors.
1202 pub fn get_and_clear_pending_events(&self) -> Vec<Event> {
1203 self.inner.lock().unwrap().get_and_clear_pending_events()
1206 pub(crate) fn get_min_seen_secret(&self) -> u64 {
1207 self.inner.lock().unwrap().get_min_seen_secret()
1210 pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
1211 self.inner.lock().unwrap().get_cur_counterparty_commitment_number()
1214 pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
1215 self.inner.lock().unwrap().get_cur_holder_commitment_number()
1218 /// Used by ChannelManager deserialization to broadcast the latest holder state if its copy of
1219 /// the Channel was out-of-date. You may use it to get a broadcastable holder toxic tx in case of
1220 /// fallen-behind, i.e when receiving a channel_reestablish with a proof that our counterparty side knows
1221 /// a higher revocation secret than the holder commitment number we are aware of. Broadcasting these
1222 /// transactions are UNSAFE, as they allow counterparty side to punish you. Nevertheless you may want to
1223 /// broadcast them if counterparty don't close channel with his higher commitment transaction after a
1224 /// substantial amount of time (a month or even a year) to get back funds. Best may be to contact
1225 /// out-of-band the other node operator to coordinate with him if option is available to you.
1226 /// In any-case, choice is up to the user.
1227 pub fn get_latest_holder_commitment_txn<L: Deref>(&self, logger: &L) -> Vec<Transaction>
1228 where L::Target: Logger {
1229 self.inner.lock().unwrap().get_latest_holder_commitment_txn(logger)
1232 /// Unsafe test-only version of get_latest_holder_commitment_txn used by our test framework
1233 /// to bypass HolderCommitmentTransaction state update lockdown after signature and generate
1234 /// revoked commitment transaction.
1235 #[cfg(any(test, feature = "unsafe_revoked_tx_signing"))]
1236 pub fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&self, logger: &L) -> Vec<Transaction>
1237 where L::Target: Logger {
1238 self.inner.lock().unwrap().unsafe_get_latest_holder_commitment_txn(logger)
1241 /// Processes transactions in a newly connected block, which may result in any of the following:
1242 /// - update the monitor's state against resolved HTLCs
1243 /// - punish the counterparty in the case of seeing a revoked commitment transaction
1244 /// - force close the channel and claim/timeout incoming/outgoing HTLCs if near expiration
1245 /// - detect settled outputs for later spending
1246 /// - schedule and bump any in-flight claims
1248 /// Returns any new outputs to watch from `txdata`; after called, these are also included in
1249 /// [`get_outputs_to_watch`].
1251 /// [`get_outputs_to_watch`]: #method.get_outputs_to_watch
1252 pub fn block_connected<B: Deref, F: Deref, L: Deref>(
1254 header: &BlockHeader,
1255 txdata: &TransactionData,
1260 ) -> Vec<(Txid, Vec<(u32, TxOut)>)>
1262 B::Target: BroadcasterInterface,
1263 F::Target: FeeEstimator,
1266 self.inner.lock().unwrap().block_connected(
1267 header, txdata, height, broadcaster, fee_estimator, logger)
1270 /// Determines if the disconnected block contained any transactions of interest and updates
1272 pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(
1274 header: &BlockHeader,
1280 B::Target: BroadcasterInterface,
1281 F::Target: FeeEstimator,
1284 self.inner.lock().unwrap().block_disconnected(
1285 header, height, broadcaster, fee_estimator, logger)
1289 impl<Signer: Sign> ChannelMonitorImpl<Signer> {
1290 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
1291 /// needed by holder commitment transactions HTCLs nor by counterparty ones. Unless we haven't already seen
1292 /// counterparty commitment transaction's secret, they are de facto pruned (we can use revocation key).
1293 fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
1294 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
1295 return Err(MonitorUpdateError("Previous secret did not match new one"));
1298 // Prune HTLCs from the previous counterparty commitment tx so we don't generate failure/fulfill
1299 // events for now-revoked/fulfilled HTLCs.
1300 if let Some(txid) = self.prev_counterparty_commitment_txid.take() {
1301 for &mut (_, ref mut source) in self.counterparty_claimable_outpoints.get_mut(&txid).unwrap() {
1306 if !self.payment_preimages.is_empty() {
1307 let cur_holder_signed_commitment_tx = &self.current_holder_commitment_tx;
1308 let prev_holder_signed_commitment_tx = self.prev_holder_signed_commitment_tx.as_ref();
1309 let min_idx = self.get_min_seen_secret();
1310 let counterparty_hash_commitment_number = &mut self.counterparty_hash_commitment_number;
1312 self.payment_preimages.retain(|&k, _| {
1313 for &(ref htlc, _, _) in cur_holder_signed_commitment_tx.htlc_outputs.iter() {
1314 if k == htlc.payment_hash {
1318 if let Some(prev_holder_commitment_tx) = prev_holder_signed_commitment_tx {
1319 for &(ref htlc, _, _) in prev_holder_commitment_tx.htlc_outputs.iter() {
1320 if k == htlc.payment_hash {
1325 let contains = if let Some(cn) = counterparty_hash_commitment_number.get(&k) {
1332 counterparty_hash_commitment_number.remove(&k);
1341 pub(crate) fn provide_latest_counterparty_commitment_tx<L: Deref>(&mut self, txid: Txid, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>, commitment_number: u64, their_revocation_point: PublicKey, logger: &L) where L::Target: Logger {
1342 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
1343 // so that a remote monitor doesn't learn anything unless there is a malicious close.
1344 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
1346 for &(ref htlc, _) in &htlc_outputs {
1347 self.counterparty_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
1350 log_trace!(logger, "Tracking new counterparty commitment transaction with txid {} at commitment number {} with {} HTLC outputs", txid, commitment_number, htlc_outputs.len());
1351 self.prev_counterparty_commitment_txid = self.current_counterparty_commitment_txid.take();
1352 self.current_counterparty_commitment_txid = Some(txid);
1353 self.counterparty_claimable_outpoints.insert(txid, htlc_outputs.clone());
1354 self.current_counterparty_commitment_number = commitment_number;
1355 //TODO: Merge this into the other per-counterparty-transaction output storage stuff
1356 match self.their_cur_revocation_points {
1357 Some(old_points) => {
1358 if old_points.0 == commitment_number + 1 {
1359 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
1360 } else if old_points.0 == commitment_number + 2 {
1361 if let Some(old_second_point) = old_points.2 {
1362 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
1364 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1367 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1371 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1374 let mut htlcs = Vec::with_capacity(htlc_outputs.len());
1375 for htlc in htlc_outputs {
1376 if htlc.0.transaction_output_index.is_some() {
1380 self.counterparty_tx_cache.per_htlc.insert(txid, htlcs);
1383 /// Informs this monitor of the latest holder (ie broadcastable) commitment transaction. The
1384 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
1385 /// is important that any clones of this channel monitor (including remote clones) by kept
1386 /// up-to-date as our holder commitment transaction is updated.
1387 /// Panics if set_on_holder_tx_csv has never been called.
1388 fn provide_latest_holder_commitment_tx(&mut self, holder_commitment_tx: HolderCommitmentTransaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), MonitorUpdateError> {
1389 // block for Rust 1.34 compat
1390 let mut new_holder_commitment_tx = {
1391 let trusted_tx = holder_commitment_tx.trust();
1392 let txid = trusted_tx.txid();
1393 let tx_keys = trusted_tx.keys();
1394 self.current_holder_commitment_number = trusted_tx.commitment_number();
1397 revocation_key: tx_keys.revocation_key,
1398 a_htlc_key: tx_keys.broadcaster_htlc_key,
1399 b_htlc_key: tx_keys.countersignatory_htlc_key,
1400 delayed_payment_key: tx_keys.broadcaster_delayed_payment_key,
1401 per_commitment_point: tx_keys.per_commitment_point,
1402 feerate_per_kw: trusted_tx.feerate_per_kw(),
1406 self.onchain_tx_handler.provide_latest_holder_tx(holder_commitment_tx);
1407 mem::swap(&mut new_holder_commitment_tx, &mut self.current_holder_commitment_tx);
1408 self.prev_holder_signed_commitment_tx = Some(new_holder_commitment_tx);
1409 if self.holder_tx_signed {
1410 return Err(MonitorUpdateError("Latest holder commitment signed has already been signed, update is rejected"));
1415 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
1416 /// commitment_tx_infos which contain the payment hash have been revoked.
1417 fn provide_payment_preimage<B: Deref, F: Deref, L: Deref>(&mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage, broadcaster: &B, fee_estimator: &F, logger: &L)
1418 where B::Target: BroadcasterInterface,
1419 F::Target: FeeEstimator,
1422 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
1424 // If the channel is force closed, try to claim the output from this preimage.
1425 // First check if a counterparty commitment transaction has been broadcasted:
1426 macro_rules! claim_htlcs {
1427 ($commitment_number: expr, $txid: expr) => {
1428 let htlc_claim_reqs = self.get_counterparty_htlc_output_claim_reqs($commitment_number, $txid, None);
1429 self.onchain_tx_handler.update_claims_view(&Vec::new(), htlc_claim_reqs, None, broadcaster, fee_estimator, logger);
1432 if let Some(txid) = self.current_counterparty_commitment_txid {
1433 if let Some(commitment_number) = self.counterparty_commitment_txn_on_chain.get(&txid) {
1434 claim_htlcs!(*commitment_number, txid);
1438 if let Some(txid) = self.prev_counterparty_commitment_txid {
1439 if let Some(commitment_number) = self.counterparty_commitment_txn_on_chain.get(&txid) {
1440 claim_htlcs!(*commitment_number, txid);
1445 // Then if a holder commitment transaction has been seen on-chain, broadcast transactions
1446 // claiming the HTLC output from each of the holder commitment transactions.
1447 // Note that we can't just use `self.holder_tx_signed`, because that only covers the case where
1448 // *we* sign a holder commitment transaction, not when e.g. a watchtower broadcasts one of our
1449 // holder commitment transactions.
1450 if self.broadcasted_holder_revokable_script.is_some() {
1451 let (claim_reqs, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx);
1452 self.onchain_tx_handler.update_claims_view(&Vec::new(), claim_reqs, None, broadcaster, fee_estimator, logger);
1453 if let Some(ref tx) = self.prev_holder_signed_commitment_tx {
1454 let (claim_reqs, _) = self.get_broadcasted_holder_claims(&tx);
1455 self.onchain_tx_handler.update_claims_view(&Vec::new(), claim_reqs, None, broadcaster, fee_estimator, logger);
1460 pub(crate) fn broadcast_latest_holder_commitment_txn<B: Deref, L: Deref>(&mut self, broadcaster: &B, logger: &L)
1461 where B::Target: BroadcasterInterface,
1464 for tx in self.get_latest_holder_commitment_txn(logger).iter() {
1465 broadcaster.broadcast_transaction(tx);
1467 self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0));
1470 pub fn update_monitor<B: Deref, F: Deref, L: Deref>(&mut self, updates: &ChannelMonitorUpdate, broadcaster: &B, fee_estimator: &F, logger: &L) -> Result<(), MonitorUpdateError>
1471 where B::Target: BroadcasterInterface,
1472 F::Target: FeeEstimator,
1475 // ChannelMonitor updates may be applied after force close if we receive a
1476 // preimage for a broadcasted commitment transaction HTLC output that we'd
1477 // like to claim on-chain. If this is the case, we no longer have guaranteed
1478 // access to the monitor's update ID, so we use a sentinel value instead.
1479 if updates.update_id == CLOSED_CHANNEL_UPDATE_ID {
1480 match updates.updates[0] {
1481 ChannelMonitorUpdateStep::PaymentPreimage { .. } => {},
1482 _ => panic!("Attempted to apply post-force-close ChannelMonitorUpdate that wasn't providing a payment preimage"),
1484 assert_eq!(updates.updates.len(), 1);
1485 } else if self.latest_update_id + 1 != updates.update_id {
1486 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
1488 for update in updates.updates.iter() {
1490 ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { commitment_tx, htlc_outputs } => {
1491 log_trace!(logger, "Updating ChannelMonitor with latest holder commitment transaction info");
1492 if self.lockdown_from_offchain { panic!(); }
1493 self.provide_latest_holder_commitment_tx(commitment_tx.clone(), htlc_outputs.clone())?
1495 ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { commitment_txid, htlc_outputs, commitment_number, their_revocation_point } => {
1496 log_trace!(logger, "Updating ChannelMonitor with latest counterparty commitment transaction info");
1497 self.provide_latest_counterparty_commitment_tx(*commitment_txid, htlc_outputs.clone(), *commitment_number, *their_revocation_point, logger)
1499 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } => {
1500 log_trace!(logger, "Updating ChannelMonitor with payment preimage");
1501 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage, broadcaster, fee_estimator, logger)
1503 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } => {
1504 log_trace!(logger, "Updating ChannelMonitor with commitment secret");
1505 self.provide_secret(*idx, *secret)?
1507 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
1508 log_trace!(logger, "Updating ChannelMonitor: channel force closed, should broadcast: {}", should_broadcast);
1509 self.lockdown_from_offchain = true;
1510 if *should_broadcast {
1511 self.broadcast_latest_holder_commitment_txn(broadcaster, logger);
1513 log_error!(logger, "You have a toxic holder commitment transaction avaible in channel monitor, read comment in ChannelMonitor::get_latest_holder_commitment_txn to be informed of manual action to take");
1518 self.latest_update_id = updates.update_id;
1522 pub fn get_latest_update_id(&self) -> u64 {
1523 self.latest_update_id
1526 pub fn get_funding_txo(&self) -> &(OutPoint, Script) {
1530 pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<(u32, Script)>> {
1531 // If we've detected a counterparty commitment tx on chain, we must include it in the set
1532 // of outputs to watch for spends of, otherwise we're likely to lose user funds. Because
1533 // its trivial to do, double-check that here.
1534 for (txid, _) in self.counterparty_commitment_txn_on_chain.iter() {
1535 self.outputs_to_watch.get(txid).expect("Counterparty commitment txn which have been broadcast should have outputs registered");
1537 &self.outputs_to_watch
1540 pub fn get_and_clear_pending_monitor_events(&mut self) -> Vec<MonitorEvent> {
1541 let mut ret = Vec::new();
1542 mem::swap(&mut ret, &mut self.pending_monitor_events);
1546 pub fn get_and_clear_pending_events(&mut self) -> Vec<Event> {
1547 let mut ret = Vec::new();
1548 mem::swap(&mut ret, &mut self.pending_events);
1552 /// Can only fail if idx is < get_min_seen_secret
1553 fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
1554 self.commitment_secrets.get_secret(idx)
1557 pub(crate) fn get_min_seen_secret(&self) -> u64 {
1558 self.commitment_secrets.get_min_seen_secret()
1561 pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
1562 self.current_counterparty_commitment_number
1565 pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
1566 self.current_holder_commitment_number
1569 /// Attempts to claim a counterparty commitment transaction's outputs using the revocation key and
1570 /// data in counterparty_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
1571 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
1572 /// HTLC-Success/HTLC-Timeout transactions.
1573 /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
1574 /// revoked counterparty commitment tx
1575 fn check_spend_counterparty_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<ClaimRequest>, (Txid, Vec<(u32, TxOut)>)) where L::Target: Logger {
1576 // Most secp and related errors trying to create keys means we have no hope of constructing
1577 // a spend transaction...so we return no transactions to broadcast
1578 let mut claimable_outpoints = Vec::new();
1579 let mut watch_outputs = Vec::new();
1581 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1582 let per_commitment_option = self.counterparty_claimable_outpoints.get(&commitment_txid);
1584 macro_rules! ignore_error {
1585 ( $thing : expr ) => {
1588 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs))
1593 let commitment_number = 0xffffffffffff - ((((tx.input[0].sequence as u64 & 0xffffff) << 3*8) | (tx.lock_time as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
1594 if commitment_number >= self.get_min_seen_secret() {
1595 let secret = self.get_secret(commitment_number).unwrap();
1596 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1597 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1598 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.holder_revocation_basepoint));
1599 let delayed_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key), &self.counterparty_tx_cache.counterparty_delayed_payment_base_key));
1601 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.counterparty_tx_cache.on_counterparty_tx_csv, &delayed_key);
1602 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1604 // First, process non-htlc outputs (to_holder & to_counterparty)
1605 for (idx, outp) in tx.output.iter().enumerate() {
1606 if outp.script_pubkey == revokeable_p2wsh {
1607 let witness_data = InputMaterial::Revoked { per_commitment_point, counterparty_delayed_payment_base_key: self.counterparty_tx_cache.counterparty_delayed_payment_base_key, counterparty_htlc_base_key: self.counterparty_tx_cache.counterparty_htlc_base_key, per_commitment_key, input_descriptor: InputDescriptors::RevokedOutput, amount: outp.value, htlc: None, on_counterparty_tx_csv: self.counterparty_tx_cache.on_counterparty_tx_csv};
1608 claimable_outpoints.push(ClaimRequest { absolute_timelock: height + self.counterparty_tx_cache.on_counterparty_tx_csv as u32, aggregable: true, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: idx as u32 }, witness_data});
1612 // Then, try to find revoked htlc outputs
1613 if let Some(ref per_commitment_data) = per_commitment_option {
1614 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1615 if let Some(transaction_output_index) = htlc.transaction_output_index {
1616 if transaction_output_index as usize >= tx.output.len() ||
1617 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1618 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1620 let witness_data = InputMaterial::Revoked { per_commitment_point, counterparty_delayed_payment_base_key: self.counterparty_tx_cache.counterparty_delayed_payment_base_key, counterparty_htlc_base_key: self.counterparty_tx_cache.counterparty_htlc_base_key, per_commitment_key, input_descriptor: if htlc.offered { InputDescriptors::RevokedOfferedHTLC } else { InputDescriptors::RevokedReceivedHTLC }, amount: tx.output[transaction_output_index as usize].value, htlc: Some(htlc.clone()), on_counterparty_tx_csv: self.counterparty_tx_cache.on_counterparty_tx_csv};
1621 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable: true, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1626 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
1627 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
1628 // We're definitely a counterparty commitment transaction!
1629 log_trace!(logger, "Got broadcast of revoked counterparty commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
1630 for (idx, outp) in tx.output.iter().enumerate() {
1631 watch_outputs.push((idx as u32, outp.clone()));
1633 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
1635 macro_rules! check_htlc_fails {
1636 ($txid: expr, $commitment_tx: expr) => {
1637 if let Some(ref outpoints) = self.counterparty_claimable_outpoints.get($txid) {
1638 for &(ref htlc, ref source_option) in outpoints.iter() {
1639 if let &Some(ref source) = source_option {
1640 log_info!(logger, "Failing HTLC with payment_hash {} from {} counterparty commitment tx due to broadcast of revoked counterparty commitment transaction, waiting for confirmation (at height {})", log_bytes!(htlc.payment_hash.0), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1641 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1642 hash_map::Entry::Occupied(mut entry) => {
1643 let e = entry.get_mut();
1644 e.retain(|ref event| {
1646 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1647 return htlc_update.0 != **source
1652 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1654 hash_map::Entry::Vacant(entry) => {
1655 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1663 if let Some(ref txid) = self.current_counterparty_commitment_txid {
1664 check_htlc_fails!(txid, "current");
1666 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
1667 check_htlc_fails!(txid, "counterparty");
1669 // No need to check holder commitment txn, symmetric HTLCSource must be present as per-htlc data on counterparty commitment tx
1671 } else if let Some(per_commitment_data) = per_commitment_option {
1672 // While this isn't useful yet, there is a potential race where if a counterparty
1673 // revokes a state at the same time as the commitment transaction for that state is
1674 // confirmed, and the watchtower receives the block before the user, the user could
1675 // upload a new ChannelMonitor with the revocation secret but the watchtower has
1676 // already processed the block, resulting in the counterparty_commitment_txn_on_chain entry
1677 // not being generated by the above conditional. Thus, to be safe, we go ahead and
1679 for (idx, outp) in tx.output.iter().enumerate() {
1680 watch_outputs.push((idx as u32, outp.clone()));
1682 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
1684 log_trace!(logger, "Got broadcast of non-revoked counterparty commitment transaction {}", commitment_txid);
1686 macro_rules! check_htlc_fails {
1687 ($txid: expr, $commitment_tx: expr, $id: tt) => {
1688 if let Some(ref latest_outpoints) = self.counterparty_claimable_outpoints.get($txid) {
1689 $id: for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1690 if let &Some(ref source) = source_option {
1691 // Check if the HTLC is present in the commitment transaction that was
1692 // broadcast, but not if it was below the dust limit, which we should
1693 // fail backwards immediately as there is no way for us to learn the
1694 // payment_preimage.
1695 // Note that if the dust limit were allowed to change between
1696 // commitment transactions we'd want to be check whether *any*
1697 // broadcastable commitment transaction has the HTLC in it, but it
1698 // cannot currently change after channel initialization, so we don't
1700 for &(ref broadcast_htlc, ref broadcast_source) in per_commitment_data.iter() {
1701 if broadcast_htlc.transaction_output_index.is_some() && Some(source) == broadcast_source.as_ref() {
1705 log_trace!(logger, "Failing HTLC with payment_hash {} from {} counterparty commitment tx due to broadcast of counterparty commitment transaction", log_bytes!(htlc.payment_hash.0), $commitment_tx);
1706 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1707 hash_map::Entry::Occupied(mut entry) => {
1708 let e = entry.get_mut();
1709 e.retain(|ref event| {
1711 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1712 return htlc_update.0 != **source
1717 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1719 hash_map::Entry::Vacant(entry) => {
1720 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1728 if let Some(ref txid) = self.current_counterparty_commitment_txid {
1729 check_htlc_fails!(txid, "current", 'current_loop);
1731 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
1732 check_htlc_fails!(txid, "previous", 'prev_loop);
1735 let htlc_claim_reqs = self.get_counterparty_htlc_output_claim_reqs(commitment_number, commitment_txid, Some(tx));
1736 for req in htlc_claim_reqs {
1737 claimable_outpoints.push(req);
1741 (claimable_outpoints, (commitment_txid, watch_outputs))
1744 fn get_counterparty_htlc_output_claim_reqs(&self, commitment_number: u64, commitment_txid: Txid, tx: Option<&Transaction>) -> Vec<ClaimRequest> {
1745 let mut claims = Vec::new();
1746 if let Some(htlc_outputs) = self.counterparty_claimable_outpoints.get(&commitment_txid) {
1747 if let Some(revocation_points) = self.their_cur_revocation_points {
1748 let revocation_point_option =
1749 // If the counterparty commitment tx is the latest valid state, use their latest
1750 // per-commitment point
1751 if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1752 else if let Some(point) = revocation_points.2.as_ref() {
1753 // If counterparty commitment tx is the state previous to the latest valid state, use
1754 // their previous per-commitment point (non-atomicity of revocation means it's valid for
1755 // them to temporarily have two valid commitment txns from our viewpoint)
1756 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1758 if let Some(revocation_point) = revocation_point_option {
1759 for (_, &(ref htlc, _)) in htlc_outputs.iter().enumerate() {
1760 if let Some(transaction_output_index) = htlc.transaction_output_index {
1761 if let Some(transaction) = tx {
1762 if transaction_output_index as usize >= transaction.output.len() ||
1763 transaction.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1764 return claims; // Corrupted per_commitment_data, fuck this user
1769 if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) {
1773 let aggregable = if !htlc.offered { false } else { true };
1774 if preimage.is_some() || !htlc.offered {
1775 let witness_data = InputMaterial::CounterpartyHTLC { per_commitment_point: *revocation_point, counterparty_delayed_payment_base_key: self.counterparty_tx_cache.counterparty_delayed_payment_base_key, counterparty_htlc_base_key: self.counterparty_tx_cache.counterparty_htlc_base_key, preimage, htlc: htlc.clone() };
1776 claims.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1786 /// Attempts to claim a counterparty HTLC-Success/HTLC-Timeout's outputs using the revocation key
1787 fn check_spend_counterparty_htlc<L: Deref>(&mut self, tx: &Transaction, commitment_number: u64, height: u32, logger: &L) -> (Vec<ClaimRequest>, Option<(Txid, Vec<(u32, TxOut)>)>) where L::Target: Logger {
1788 let htlc_txid = tx.txid();
1789 if tx.input.len() != 1 || tx.output.len() != 1 || tx.input[0].witness.len() != 5 {
1790 return (Vec::new(), None)
1793 macro_rules! ignore_error {
1794 ( $thing : expr ) => {
1797 Err(_) => return (Vec::new(), None)
1802 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
1803 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1804 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1806 log_trace!(logger, "Counterparty HTLC broadcast {}:{}", htlc_txid, 0);
1807 let witness_data = InputMaterial::Revoked { per_commitment_point, counterparty_delayed_payment_base_key: self.counterparty_tx_cache.counterparty_delayed_payment_base_key, counterparty_htlc_base_key: self.counterparty_tx_cache.counterparty_htlc_base_key, per_commitment_key, input_descriptor: InputDescriptors::RevokedOutput, amount: tx.output[0].value, htlc: None, on_counterparty_tx_csv: self.counterparty_tx_cache.on_counterparty_tx_csv };
1808 let claimable_outpoints = vec!(ClaimRequest { absolute_timelock: height + self.counterparty_tx_cache.on_counterparty_tx_csv as u32, aggregable: true, outpoint: BitcoinOutPoint { txid: htlc_txid, vout: 0}, witness_data });
1809 let outputs = vec![(0, tx.output[0].clone())];
1810 (claimable_outpoints, Some((htlc_txid, outputs)))
1813 // Returns (1) `ClaimRequest`s that can be given to the OnChainTxHandler, so that the handler can
1814 // broadcast transactions claiming holder HTLC commitment outputs and (2) a holder revokable
1815 // script so we can detect whether a holder transaction has been seen on-chain.
1816 fn get_broadcasted_holder_claims(&self, holder_tx: &HolderSignedTx) -> (Vec<ClaimRequest>, Option<(Script, PublicKey, PublicKey)>) {
1817 let mut claim_requests = Vec::with_capacity(holder_tx.htlc_outputs.len());
1819 let redeemscript = chan_utils::get_revokeable_redeemscript(&holder_tx.revocation_key, self.on_holder_tx_csv, &holder_tx.delayed_payment_key);
1820 let broadcasted_holder_revokable_script = Some((redeemscript.to_v0_p2wsh(), holder_tx.per_commitment_point.clone(), holder_tx.revocation_key.clone()));
1822 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
1823 if let Some(transaction_output_index) = htlc.transaction_output_index {
1824 claim_requests.push(ClaimRequest { absolute_timelock: ::std::u32::MAX, aggregable: false, outpoint: BitcoinOutPoint { txid: holder_tx.txid, vout: transaction_output_index as u32 },
1825 witness_data: InputMaterial::HolderHTLC {
1826 preimage: if !htlc.offered {
1827 if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1828 Some(preimage.clone())
1830 // We can't build an HTLC-Success transaction without the preimage
1834 amount: htlc.amount_msat,
1839 (claim_requests, broadcasted_holder_revokable_script)
1842 // Returns holder HTLC outputs to watch and react to in case of spending.
1843 fn get_broadcasted_holder_watch_outputs(&self, holder_tx: &HolderSignedTx, commitment_tx: &Transaction) -> Vec<(u32, TxOut)> {
1844 let mut watch_outputs = Vec::with_capacity(holder_tx.htlc_outputs.len());
1845 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
1846 if let Some(transaction_output_index) = htlc.transaction_output_index {
1847 watch_outputs.push((transaction_output_index, commitment_tx.output[transaction_output_index as usize].clone()));
1853 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1854 /// revoked using data in holder_claimable_outpoints.
1855 /// Should not be used if check_spend_revoked_transaction succeeds.
1856 fn check_spend_holder_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<ClaimRequest>, (Txid, Vec<(u32, TxOut)>)) where L::Target: Logger {
1857 let commitment_txid = tx.txid();
1858 let mut claim_requests = Vec::new();
1859 let mut watch_outputs = Vec::new();
1861 macro_rules! wait_threshold_conf {
1862 ($height: expr, $source: expr, $commitment_tx: expr, $payment_hash: expr) => {
1863 log_trace!(logger, "Failing HTLC with payment_hash {} from {} holder commitment tx due to broadcast of transaction, waiting confirmation (at height{})", log_bytes!($payment_hash.0), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1864 match self.onchain_events_waiting_threshold_conf.entry($height + ANTI_REORG_DELAY - 1) {
1865 hash_map::Entry::Occupied(mut entry) => {
1866 let e = entry.get_mut();
1867 e.retain(|ref event| {
1869 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1870 return htlc_update.0 != $source
1875 e.push(OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)});
1877 hash_map::Entry::Vacant(entry) => {
1878 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)}]);
1884 macro_rules! append_onchain_update {
1885 ($updates: expr, $to_watch: expr) => {
1886 claim_requests = $updates.0;
1887 self.broadcasted_holder_revokable_script = $updates.1;
1888 watch_outputs.append(&mut $to_watch);
1892 // HTLCs set may differ between last and previous holder commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
1893 let mut is_holder_tx = false;
1895 if self.current_holder_commitment_tx.txid == commitment_txid {
1896 is_holder_tx = true;
1897 log_trace!(logger, "Got latest holder commitment tx broadcast, searching for available HTLCs to claim");
1898 let res = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx);
1899 let mut to_watch = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, tx);
1900 append_onchain_update!(res, to_watch);
1901 } else if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
1902 if holder_tx.txid == commitment_txid {
1903 is_holder_tx = true;
1904 log_trace!(logger, "Got previous holder commitment tx broadcast, searching for available HTLCs to claim");
1905 let res = self.get_broadcasted_holder_claims(holder_tx);
1906 let mut to_watch = self.get_broadcasted_holder_watch_outputs(holder_tx, tx);
1907 append_onchain_update!(res, to_watch);
1911 macro_rules! fail_dust_htlcs_after_threshold_conf {
1912 ($holder_tx: expr) => {
1913 for &(ref htlc, _, ref source) in &$holder_tx.htlc_outputs {
1914 if htlc.transaction_output_index.is_none() {
1915 if let &Some(ref source) = source {
1916 wait_threshold_conf!(height, source.clone(), "lastest", htlc.payment_hash.clone());
1924 fail_dust_htlcs_after_threshold_conf!(self.current_holder_commitment_tx);
1925 if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
1926 fail_dust_htlcs_after_threshold_conf!(holder_tx);
1930 (claim_requests, (commitment_txid, watch_outputs))
1933 pub fn get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1934 log_trace!(logger, "Getting signed latest holder commitment transaction!");
1935 self.holder_tx_signed = true;
1936 let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
1937 let txid = commitment_tx.txid();
1938 let mut res = vec![commitment_tx];
1939 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
1940 if let Some(vout) = htlc.0.transaction_output_index {
1941 let preimage = if !htlc.0.offered {
1942 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1943 // We can't build an HTLC-Success transaction without the preimage
1947 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
1948 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1953 // We throw away the generated waiting_first_conf data as we aren't (yet) confirmed and we don't actually know what the caller wants to do.
1954 // The data will be re-generated and tracked in check_spend_holder_transaction if we get a confirmation.
1958 #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]
1959 fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1960 log_trace!(logger, "Getting signed copy of latest holder commitment transaction!");
1961 let commitment_tx = self.onchain_tx_handler.get_fully_signed_copy_holder_tx(&self.funding_redeemscript);
1962 let txid = commitment_tx.txid();
1963 let mut res = vec![commitment_tx];
1964 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
1965 if let Some(vout) = htlc.0.transaction_output_index {
1966 let preimage = if !htlc.0.offered {
1967 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1968 // We can't build an HTLC-Success transaction without the preimage
1972 if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
1973 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1981 pub fn block_connected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, txdata: &TransactionData, height: u32, broadcaster: B, fee_estimator: F, logger: L)-> Vec<(Txid, Vec<(u32, TxOut)>)>
1982 where B::Target: BroadcasterInterface,
1983 F::Target: FeeEstimator,
1986 let txn_matched = self.filter_block(txdata);
1987 for tx in &txn_matched {
1988 let mut output_val = 0;
1989 for out in tx.output.iter() {
1990 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1991 output_val += out.value;
1992 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1996 let block_hash = header.block_hash();
1997 log_trace!(logger, "Block {} at height {} connected with {} txn matched", block_hash, height, txn_matched.len());
1999 let mut watch_outputs = Vec::new();
2000 let mut claimable_outpoints = Vec::new();
2001 for tx in &txn_matched {
2002 if tx.input.len() == 1 {
2003 // Assuming our keys were not leaked (in which case we're screwed no matter what),
2004 // commitment transactions and HTLC transactions will all only ever have one input,
2005 // which is an easy way to filter out any potential non-matching txn for lazy
2007 let prevout = &tx.input[0].previous_output;
2008 if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
2009 if (tx.input[0].sequence >> 8*3) as u8 == 0x80 && (tx.lock_time >> 8*3) as u8 == 0x20 {
2010 let (mut new_outpoints, new_outputs) = self.check_spend_counterparty_transaction(&tx, height, &logger);
2011 if !new_outputs.1.is_empty() {
2012 watch_outputs.push(new_outputs);
2014 if new_outpoints.is_empty() {
2015 let (mut new_outpoints, new_outputs) = self.check_spend_holder_transaction(&tx, height, &logger);
2016 if !new_outputs.1.is_empty() {
2017 watch_outputs.push(new_outputs);
2019 claimable_outpoints.append(&mut new_outpoints);
2021 claimable_outpoints.append(&mut new_outpoints);
2024 if let Some(&commitment_number) = self.counterparty_commitment_txn_on_chain.get(&prevout.txid) {
2025 let (mut new_outpoints, new_outputs_option) = self.check_spend_counterparty_htlc(&tx, commitment_number, height, &logger);
2026 claimable_outpoints.append(&mut new_outpoints);
2027 if let Some(new_outputs) = new_outputs_option {
2028 watch_outputs.push(new_outputs);
2033 // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
2034 // can also be resolved in a few other ways which can have more than one output. Thus,
2035 // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
2036 self.is_resolving_htlc_output(&tx, height, &logger);
2038 self.is_paying_spendable_output(&tx, height, &logger);
2040 let should_broadcast = self.would_broadcast_at_height(height, &logger);
2041 if should_broadcast {
2042 claimable_outpoints.push(ClaimRequest { absolute_timelock: height, aggregable: false, outpoint: BitcoinOutPoint { txid: self.funding_info.0.txid.clone(), vout: self.funding_info.0.index as u32 }, witness_data: InputMaterial::Funding { funding_redeemscript: self.funding_redeemscript.clone() }});
2044 if should_broadcast {
2045 self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0));
2046 let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
2047 self.holder_tx_signed = true;
2048 let (mut new_outpoints, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx);
2049 let new_outputs = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, &commitment_tx);
2050 if !new_outputs.is_empty() {
2051 watch_outputs.push((self.current_holder_commitment_tx.txid.clone(), new_outputs));
2053 claimable_outpoints.append(&mut new_outpoints);
2055 if let Some(events) = self.onchain_events_waiting_threshold_conf.remove(&height) {
2058 OnchainEvent::HTLCUpdate { htlc_update } => {
2059 log_trace!(logger, "HTLC {} failure update has got enough confirmations to be passed upstream", log_bytes!((htlc_update.1).0));
2060 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2061 payment_hash: htlc_update.1,
2062 payment_preimage: None,
2063 source: htlc_update.0,
2066 OnchainEvent::MaturingOutput { descriptor } => {
2067 log_trace!(logger, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
2068 self.pending_events.push(Event::SpendableOutputs {
2069 outputs: vec![descriptor]
2076 self.onchain_tx_handler.update_claims_view(&txn_matched, claimable_outpoints, Some(height), &&*broadcaster, &&*fee_estimator, &&*logger);
2077 self.last_block_hash = block_hash;
2079 // Determine new outputs to watch by comparing against previously known outputs to watch,
2080 // updating the latter in the process.
2081 watch_outputs.retain(|&(ref txid, ref txouts)| {
2082 let idx_and_scripts = txouts.iter().map(|o| (o.0, o.1.script_pubkey.clone())).collect();
2083 self.outputs_to_watch.insert(txid.clone(), idx_and_scripts).is_none()
2087 // If we see a transaction for which we registered outputs previously,
2088 // make sure the registered scriptpubkey at the expected index match
2089 // the actual transaction output one. We failed this case before #653.
2090 for tx in &txn_matched {
2091 if let Some(outputs) = self.get_outputs_to_watch().get(&tx.txid()) {
2092 for idx_and_script in outputs.iter() {
2093 assert!((idx_and_script.0 as usize) < tx.output.len());
2094 assert_eq!(tx.output[idx_and_script.0 as usize].script_pubkey, idx_and_script.1);
2102 pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, height: u32, broadcaster: B, fee_estimator: F, logger: L)
2103 where B::Target: BroadcasterInterface,
2104 F::Target: FeeEstimator,
2107 log_trace!(logger, "Block {} at height {} disconnected", header.block_hash(), height);
2109 if let Some(_) = self.onchain_events_waiting_threshold_conf.remove(&(height + ANTI_REORG_DELAY - 1)) {
2111 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
2112 //- maturing spendable output has transaction paying us has been disconnected
2115 self.onchain_tx_handler.block_disconnected(height, broadcaster, fee_estimator, logger);
2117 self.last_block_hash = header.prev_blockhash;
2120 /// Filters a block's `txdata` for transactions spending watched outputs or for any child
2121 /// transactions thereof.
2122 fn filter_block<'a>(&self, txdata: &TransactionData<'a>) -> Vec<&'a Transaction> {
2123 let mut matched_txn = HashSet::new();
2124 txdata.iter().filter(|&&(_, tx)| {
2125 let mut matches = self.spends_watched_output(tx);
2126 for input in tx.input.iter() {
2127 if matches { break; }
2128 if matched_txn.contains(&input.previous_output.txid) {
2133 matched_txn.insert(tx.txid());
2136 }).map(|(_, tx)| *tx).collect()
2139 /// Checks if a given transaction spends any watched outputs.
2140 fn spends_watched_output(&self, tx: &Transaction) -> bool {
2141 for input in tx.input.iter() {
2142 if let Some(outputs) = self.get_outputs_to_watch().get(&input.previous_output.txid) {
2143 for (idx, _script_pubkey) in outputs.iter() {
2144 if *idx == input.previous_output.vout {
2147 // If the expected script is a known type, check that the witness
2148 // appears to be spending the correct type (ie that the match would
2149 // actually succeed in BIP 158/159-style filters).
2150 if _script_pubkey.is_v0_p2wsh() {
2151 assert_eq!(&bitcoin::Address::p2wsh(&Script::from(input.witness.last().unwrap().clone()), bitcoin::Network::Bitcoin).script_pubkey(), _script_pubkey);
2152 } else if _script_pubkey.is_v0_p2wpkh() {
2153 assert_eq!(&bitcoin::Address::p2wpkh(&bitcoin::PublicKey::from_slice(&input.witness.last().unwrap()).unwrap(), bitcoin::Network::Bitcoin).unwrap().script_pubkey(), _script_pubkey);
2154 } else { panic!(); }
2165 fn would_broadcast_at_height<L: Deref>(&self, height: u32, logger: &L) -> bool where L::Target: Logger {
2166 // We need to consider all HTLCs which are:
2167 // * in any unrevoked counterparty commitment transaction, as they could broadcast said
2168 // transactions and we'd end up in a race, or
2169 // * are in our latest holder commitment transaction, as this is the thing we will
2170 // broadcast if we go on-chain.
2171 // Note that we consider HTLCs which were below dust threshold here - while they don't
2172 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
2173 // to the source, and if we don't fail the channel we will have to ensure that the next
2174 // updates that peer sends us are update_fails, failing the channel if not. It's probably
2175 // easier to just fail the channel as this case should be rare enough anyway.
2176 macro_rules! scan_commitment {
2177 ($htlcs: expr, $holder_tx: expr) => {
2178 for ref htlc in $htlcs {
2179 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
2180 // chain with enough room to claim the HTLC without our counterparty being able to
2181 // time out the HTLC first.
2182 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
2183 // concern is being able to claim the corresponding inbound HTLC (on another
2184 // channel) before it expires. In fact, we don't even really care if our
2185 // counterparty here claims such an outbound HTLC after it expired as long as we
2186 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
2187 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
2188 // we give ourselves a few blocks of headroom after expiration before going
2189 // on-chain for an expired HTLC.
2190 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
2191 // from us until we've reached the point where we go on-chain with the
2192 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
2193 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
2194 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
2195 // inbound_cltv == height + CLTV_CLAIM_BUFFER
2196 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
2197 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
2198 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
2199 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
2200 // The final, above, condition is checked for statically in channelmanager
2201 // with CHECK_CLTV_EXPIRY_SANITY_2.
2202 let htlc_outbound = $holder_tx == htlc.offered;
2203 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
2204 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
2205 log_info!(logger, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
2212 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
2214 if let Some(ref txid) = self.current_counterparty_commitment_txid {
2215 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
2216 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2219 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
2220 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
2221 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2228 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a holder
2229 /// or counterparty commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
2230 fn is_resolving_htlc_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2231 'outer_loop: for input in &tx.input {
2232 let mut payment_data = None;
2233 let revocation_sig_claim = (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && input.witness[1].len() == 33)
2234 || (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && input.witness[1].len() == 33);
2235 let accepted_preimage_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::AcceptedHTLC);
2236 let offered_preimage_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC);
2238 macro_rules! log_claim {
2239 ($tx_info: expr, $holder_tx: expr, $htlc: expr, $source_avail: expr) => {
2240 // We found the output in question, but aren't failing it backwards
2241 // as we have no corresponding source and no valid counterparty commitment txid
2242 // to try a weak source binding with same-hash, same-value still-valid offered HTLC.
2243 // This implies either it is an inbound HTLC or an outbound HTLC on a revoked transaction.
2244 let outbound_htlc = $holder_tx == $htlc.offered;
2245 if ($holder_tx && revocation_sig_claim) ||
2246 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
2247 log_error!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
2248 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2249 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2250 if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back" });
2252 log_info!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
2253 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2254 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2255 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
2260 macro_rules! check_htlc_valid_counterparty {
2261 ($counterparty_txid: expr, $htlc_output: expr) => {
2262 if let Some(txid) = $counterparty_txid {
2263 for &(ref pending_htlc, ref pending_source) in self.counterparty_claimable_outpoints.get(&txid).unwrap() {
2264 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
2265 if let &Some(ref source) = pending_source {
2266 log_claim!("revoked counterparty commitment tx", false, pending_htlc, true);
2267 payment_data = Some(((**source).clone(), $htlc_output.payment_hash));
2276 macro_rules! scan_commitment {
2277 ($htlcs: expr, $tx_info: expr, $holder_tx: expr) => {
2278 for (ref htlc_output, source_option) in $htlcs {
2279 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
2280 if let Some(ref source) = source_option {
2281 log_claim!($tx_info, $holder_tx, htlc_output, true);
2282 // We have a resolution of an HTLC either from one of our latest
2283 // holder commitment transactions or an unrevoked counterparty commitment
2284 // transaction. This implies we either learned a preimage, the HTLC
2285 // has timed out, or we screwed up. In any case, we should now
2286 // resolve the source HTLC with the original sender.
2287 payment_data = Some(((*source).clone(), htlc_output.payment_hash));
2288 } else if !$holder_tx {
2289 check_htlc_valid_counterparty!(self.current_counterparty_commitment_txid, htlc_output);
2290 if payment_data.is_none() {
2291 check_htlc_valid_counterparty!(self.prev_counterparty_commitment_txid, htlc_output);
2294 if payment_data.is_none() {
2295 log_claim!($tx_info, $holder_tx, htlc_output, false);
2296 continue 'outer_loop;
2303 if input.previous_output.txid == self.current_holder_commitment_tx.txid {
2304 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2305 "our latest holder commitment tx", true);
2307 if let Some(ref prev_holder_signed_commitment_tx) = self.prev_holder_signed_commitment_tx {
2308 if input.previous_output.txid == prev_holder_signed_commitment_tx.txid {
2309 scan_commitment!(prev_holder_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2310 "our previous holder commitment tx", true);
2313 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(&input.previous_output.txid) {
2314 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
2315 "counterparty commitment tx", false);
2318 // Check that scan_commitment, above, decided there is some source worth relaying an
2319 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
2320 if let Some((source, payment_hash)) = payment_data {
2321 let mut payment_preimage = PaymentPreimage([0; 32]);
2322 if accepted_preimage_claim {
2323 if !self.pending_monitor_events.iter().any(
2324 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update { upd.source == source } else { false }) {
2325 payment_preimage.0.copy_from_slice(&input.witness[3]);
2326 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2328 payment_preimage: Some(payment_preimage),
2332 } else if offered_preimage_claim {
2333 if !self.pending_monitor_events.iter().any(
2334 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update {
2335 upd.source == source
2337 payment_preimage.0.copy_from_slice(&input.witness[1]);
2338 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2340 payment_preimage: Some(payment_preimage),
2345 log_info!(logger, "Failing HTLC with payment_hash {} timeout by a spend tx, waiting for confirmation (at height{})", log_bytes!(payment_hash.0), height + ANTI_REORG_DELAY - 1);
2346 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2347 hash_map::Entry::Occupied(mut entry) => {
2348 let e = entry.get_mut();
2349 e.retain(|ref event| {
2351 OnchainEvent::HTLCUpdate { ref htlc_update } => {
2352 return htlc_update.0 != source
2357 e.push(OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)});
2359 hash_map::Entry::Vacant(entry) => {
2360 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)}]);
2368 /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
2369 fn is_paying_spendable_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2370 let mut spendable_output = None;
2371 for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
2372 if i > ::std::u16::MAX as usize {
2373 // While it is possible that an output exists on chain which is greater than the
2374 // 2^16th output in a given transaction, this is only possible if the output is not
2375 // in a lightning transaction and was instead placed there by some third party who
2376 // wishes to give us money for no reason.
2377 // Namely, any lightning transactions which we pre-sign will never have anywhere
2378 // near 2^16 outputs both because such transactions must have ~2^16 outputs who's
2379 // scripts are not longer than one byte in length and because they are inherently
2380 // non-standard due to their size.
2381 // Thus, it is completely safe to ignore such outputs, and while it may result in
2382 // us ignoring non-lightning fund to us, that is only possible if someone fills
2383 // nearly a full block with garbage just to hit this case.
2386 if outp.script_pubkey == self.destination_script {
2387 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2388 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2389 output: outp.clone(),
2392 } else if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
2393 if broadcasted_holder_revokable_script.0 == outp.script_pubkey {
2394 spendable_output = Some(SpendableOutputDescriptor::DelayedPaymentOutput(DelayedPaymentOutputDescriptor {
2395 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2396 per_commitment_point: broadcasted_holder_revokable_script.1,
2397 to_self_delay: self.on_holder_tx_csv,
2398 output: outp.clone(),
2399 revocation_pubkey: broadcasted_holder_revokable_script.2.clone(),
2400 channel_keys_id: self.channel_keys_id,
2401 channel_value_satoshis: self.channel_value_satoshis,
2405 } else if self.counterparty_payment_script == outp.script_pubkey {
2406 spendable_output = Some(SpendableOutputDescriptor::StaticPaymentOutput(StaticPaymentOutputDescriptor {
2407 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2408 output: outp.clone(),
2409 channel_keys_id: self.channel_keys_id,
2410 channel_value_satoshis: self.channel_value_satoshis,
2413 } else if outp.script_pubkey == self.shutdown_script {
2414 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2415 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2416 output: outp.clone(),
2420 if let Some(spendable_output) = spendable_output {
2421 log_trace!(logger, "Maturing {} until {}", log_spendable!(spendable_output), height + ANTI_REORG_DELAY - 1);
2422 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2423 hash_map::Entry::Occupied(mut entry) => {
2424 let e = entry.get_mut();
2425 e.push(OnchainEvent::MaturingOutput { descriptor: spendable_output });
2427 hash_map::Entry::Vacant(entry) => {
2428 entry.insert(vec![OnchainEvent::MaturingOutput { descriptor: spendable_output }]);
2435 /// `Persist` defines behavior for persisting channel monitors: this could mean
2436 /// writing once to disk, and/or uploading to one or more backup services.
2438 /// Note that for every new monitor, you **must** persist the new `ChannelMonitor`
2439 /// to disk/backups. And, on every update, you **must** persist either the
2440 /// `ChannelMonitorUpdate` or the updated monitor itself. Otherwise, there is risk
2441 /// of situations such as revoking a transaction, then crashing before this
2442 /// revocation can be persisted, then unintentionally broadcasting a revoked
2443 /// transaction and losing money. This is a risk because previous channel states
2444 /// are toxic, so it's important that whatever channel state is persisted is
2445 /// kept up-to-date.
2446 pub trait Persist<ChannelSigner: Sign>: Send + Sync {
2447 /// Persist a new channel's data. The data can be stored any way you want, but
2448 /// the identifier provided by Rust-Lightning is the channel's outpoint (and
2449 /// it is up to you to maintain a correct mapping between the outpoint and the
2450 /// stored channel data). Note that you **must** persist every new monitor to
2451 /// disk. See the `Persist` trait documentation for more details.
2453 /// See [`ChannelMonitor::serialize_for_disk`] for writing out a `ChannelMonitor`,
2454 /// and [`ChannelMonitorUpdateErr`] for requirements when returning errors.
2456 /// [`ChannelMonitor::serialize_for_disk`]: struct.ChannelMonitor.html#method.serialize_for_disk
2457 /// [`ChannelMonitorUpdateErr`]: enum.ChannelMonitorUpdateErr.html
2458 fn persist_new_channel(&self, id: OutPoint, data: &ChannelMonitor<ChannelSigner>) -> Result<(), ChannelMonitorUpdateErr>;
2460 /// Update one channel's data. The provided `ChannelMonitor` has already
2461 /// applied the given update.
2463 /// Note that on every update, you **must** persist either the
2464 /// `ChannelMonitorUpdate` or the updated monitor itself to disk/backups. See
2465 /// the `Persist` trait documentation for more details.
2467 /// If an implementer chooses to persist the updates only, they need to make
2468 /// sure that all the updates are applied to the `ChannelMonitors` *before*
2469 /// the set of channel monitors is given to the `ChannelManager`
2470 /// deserialization routine. See [`ChannelMonitor::update_monitor`] for
2471 /// applying a monitor update to a monitor. If full `ChannelMonitors` are
2472 /// persisted, then there is no need to persist individual updates.
2474 /// Note that there could be a performance tradeoff between persisting complete
2475 /// channel monitors on every update vs. persisting only updates and applying
2476 /// them in batches. The size of each monitor grows `O(number of state updates)`
2477 /// whereas updates are small and `O(1)`.
2479 /// See [`ChannelMonitor::serialize_for_disk`] for writing out a `ChannelMonitor`,
2480 /// [`ChannelMonitorUpdate::write`] for writing out an update, and
2481 /// [`ChannelMonitorUpdateErr`] for requirements when returning errors.
2483 /// [`ChannelMonitor::update_monitor`]: struct.ChannelMonitor.html#impl-1
2484 /// [`ChannelMonitor::serialize_for_disk`]: struct.ChannelMonitor.html#method.serialize_for_disk
2485 /// [`ChannelMonitorUpdate::write`]: struct.ChannelMonitorUpdate.html#method.write
2486 /// [`ChannelMonitorUpdateErr`]: enum.ChannelMonitorUpdateErr.html
2487 fn update_persisted_channel(&self, id: OutPoint, update: &ChannelMonitorUpdate, data: &ChannelMonitor<ChannelSigner>) -> Result<(), ChannelMonitorUpdateErr>;
2490 impl<Signer: Sign, T: Deref, F: Deref, L: Deref> chain::Listen for (ChannelMonitor<Signer>, T, F, L)
2492 T::Target: BroadcasterInterface,
2493 F::Target: FeeEstimator,
2496 fn block_connected(&self, block: &Block, height: u32) {
2497 let txdata: Vec<_> = block.txdata.iter().enumerate().collect();
2498 self.0.block_connected(&block.header, &txdata, height, &*self.1, &*self.2, &*self.3);
2501 fn block_disconnected(&self, header: &BlockHeader, height: u32) {
2502 self.0.block_disconnected(header, height, &*self.1, &*self.2, &*self.3);
2506 const MAX_ALLOC_SIZE: usize = 64*1024;
2508 impl<'a, Signer: Sign, K: KeysInterface<Signer = Signer>> ReadableArgs<&'a K>
2509 for (BlockHash, ChannelMonitor<Signer>) {
2510 fn read<R: ::std::io::Read>(reader: &mut R, keys_manager: &'a K) -> Result<Self, DecodeError> {
2511 macro_rules! unwrap_obj {
2515 Err(_) => return Err(DecodeError::InvalidValue),
2520 let _ver: u8 = Readable::read(reader)?;
2521 let min_ver: u8 = Readable::read(reader)?;
2522 if min_ver > SERIALIZATION_VERSION {
2523 return Err(DecodeError::UnknownVersion);
2526 let latest_update_id: u64 = Readable::read(reader)?;
2527 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
2529 let destination_script = Readable::read(reader)?;
2530 let broadcasted_holder_revokable_script = match <u8 as Readable>::read(reader)? {
2532 let revokable_address = Readable::read(reader)?;
2533 let per_commitment_point = Readable::read(reader)?;
2534 let revokable_script = Readable::read(reader)?;
2535 Some((revokable_address, per_commitment_point, revokable_script))
2538 _ => return Err(DecodeError::InvalidValue),
2540 let counterparty_payment_script = Readable::read(reader)?;
2541 let shutdown_script = Readable::read(reader)?;
2543 let channel_keys_id = Readable::read(reader)?;
2544 let holder_revocation_basepoint = Readable::read(reader)?;
2545 // Technically this can fail and serialize fail a round-trip, but only for serialization of
2546 // barely-init'd ChannelMonitors that we can't do anything with.
2547 let outpoint = OutPoint {
2548 txid: Readable::read(reader)?,
2549 index: Readable::read(reader)?,
2551 let funding_info = (outpoint, Readable::read(reader)?);
2552 let current_counterparty_commitment_txid = Readable::read(reader)?;
2553 let prev_counterparty_commitment_txid = Readable::read(reader)?;
2555 let counterparty_tx_cache = Readable::read(reader)?;
2556 let funding_redeemscript = Readable::read(reader)?;
2557 let channel_value_satoshis = Readable::read(reader)?;
2559 let their_cur_revocation_points = {
2560 let first_idx = <U48 as Readable>::read(reader)?.0;
2564 let first_point = Readable::read(reader)?;
2565 let second_point_slice: [u8; 33] = Readable::read(reader)?;
2566 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
2567 Some((first_idx, first_point, None))
2569 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
2574 let on_holder_tx_csv: u16 = Readable::read(reader)?;
2576 let commitment_secrets = Readable::read(reader)?;
2578 macro_rules! read_htlc_in_commitment {
2581 let offered: bool = Readable::read(reader)?;
2582 let amount_msat: u64 = Readable::read(reader)?;
2583 let cltv_expiry: u32 = Readable::read(reader)?;
2584 let payment_hash: PaymentHash = Readable::read(reader)?;
2585 let transaction_output_index: Option<u32> = Readable::read(reader)?;
2587 HTLCOutputInCommitment {
2588 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
2594 let counterparty_claimable_outpoints_len: u64 = Readable::read(reader)?;
2595 let mut counterparty_claimable_outpoints = HashMap::with_capacity(cmp::min(counterparty_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
2596 for _ in 0..counterparty_claimable_outpoints_len {
2597 let txid: Txid = Readable::read(reader)?;
2598 let htlcs_count: u64 = Readable::read(reader)?;
2599 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
2600 for _ in 0..htlcs_count {
2601 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
2603 if let Some(_) = counterparty_claimable_outpoints.insert(txid, htlcs) {
2604 return Err(DecodeError::InvalidValue);
2608 let counterparty_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
2609 let mut counterparty_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(counterparty_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
2610 for _ in 0..counterparty_commitment_txn_on_chain_len {
2611 let txid: Txid = Readable::read(reader)?;
2612 let commitment_number = <U48 as Readable>::read(reader)?.0;
2613 if let Some(_) = counterparty_commitment_txn_on_chain.insert(txid, commitment_number) {
2614 return Err(DecodeError::InvalidValue);
2618 let counterparty_hash_commitment_number_len: u64 = Readable::read(reader)?;
2619 let mut counterparty_hash_commitment_number = HashMap::with_capacity(cmp::min(counterparty_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
2620 for _ in 0..counterparty_hash_commitment_number_len {
2621 let payment_hash: PaymentHash = Readable::read(reader)?;
2622 let commitment_number = <U48 as Readable>::read(reader)?.0;
2623 if let Some(_) = counterparty_hash_commitment_number.insert(payment_hash, commitment_number) {
2624 return Err(DecodeError::InvalidValue);
2628 macro_rules! read_holder_tx {
2631 let txid = Readable::read(reader)?;
2632 let revocation_key = Readable::read(reader)?;
2633 let a_htlc_key = Readable::read(reader)?;
2634 let b_htlc_key = Readable::read(reader)?;
2635 let delayed_payment_key = Readable::read(reader)?;
2636 let per_commitment_point = Readable::read(reader)?;
2637 let feerate_per_kw: u32 = Readable::read(reader)?;
2639 let htlcs_len: u64 = Readable::read(reader)?;
2640 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_len as usize, MAX_ALLOC_SIZE / 128));
2641 for _ in 0..htlcs_len {
2642 let htlc = read_htlc_in_commitment!();
2643 let sigs = match <u8 as Readable>::read(reader)? {
2645 1 => Some(Readable::read(reader)?),
2646 _ => return Err(DecodeError::InvalidValue),
2648 htlcs.push((htlc, sigs, Readable::read(reader)?));
2653 revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, per_commitment_point, feerate_per_kw,
2660 let prev_holder_signed_commitment_tx = match <u8 as Readable>::read(reader)? {
2663 Some(read_holder_tx!())
2665 _ => return Err(DecodeError::InvalidValue),
2667 let current_holder_commitment_tx = read_holder_tx!();
2669 let current_counterparty_commitment_number = <U48 as Readable>::read(reader)?.0;
2670 let current_holder_commitment_number = <U48 as Readable>::read(reader)?.0;
2672 let payment_preimages_len: u64 = Readable::read(reader)?;
2673 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
2674 for _ in 0..payment_preimages_len {
2675 let preimage: PaymentPreimage = Readable::read(reader)?;
2676 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2677 if let Some(_) = payment_preimages.insert(hash, preimage) {
2678 return Err(DecodeError::InvalidValue);
2682 let pending_monitor_events_len: u64 = Readable::read(reader)?;
2683 let mut pending_monitor_events = Vec::with_capacity(cmp::min(pending_monitor_events_len as usize, MAX_ALLOC_SIZE / (32 + 8*3)));
2684 for _ in 0..pending_monitor_events_len {
2685 let ev = match <u8 as Readable>::read(reader)? {
2686 0 => MonitorEvent::HTLCEvent(Readable::read(reader)?),
2687 1 => MonitorEvent::CommitmentTxBroadcasted(funding_info.0),
2688 _ => return Err(DecodeError::InvalidValue)
2690 pending_monitor_events.push(ev);
2693 let pending_events_len: u64 = Readable::read(reader)?;
2694 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Event>()));
2695 for _ in 0..pending_events_len {
2696 if let Some(event) = MaybeReadable::read(reader)? {
2697 pending_events.push(event);
2701 let last_block_hash: BlockHash = Readable::read(reader)?;
2703 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
2704 let mut onchain_events_waiting_threshold_conf = HashMap::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
2705 for _ in 0..waiting_threshold_conf_len {
2706 let height_target = Readable::read(reader)?;
2707 let events_len: u64 = Readable::read(reader)?;
2708 let mut events = Vec::with_capacity(cmp::min(events_len as usize, MAX_ALLOC_SIZE / 128));
2709 for _ in 0..events_len {
2710 let ev = match <u8 as Readable>::read(reader)? {
2712 let htlc_source = Readable::read(reader)?;
2713 let hash = Readable::read(reader)?;
2714 OnchainEvent::HTLCUpdate {
2715 htlc_update: (htlc_source, hash)
2719 let descriptor = Readable::read(reader)?;
2720 OnchainEvent::MaturingOutput {
2724 _ => return Err(DecodeError::InvalidValue),
2728 onchain_events_waiting_threshold_conf.insert(height_target, events);
2731 let outputs_to_watch_len: u64 = Readable::read(reader)?;
2732 let mut outputs_to_watch = HashMap::with_capacity(cmp::min(outputs_to_watch_len as usize, MAX_ALLOC_SIZE / (mem::size_of::<Txid>() + mem::size_of::<u32>() + mem::size_of::<Vec<Script>>())));
2733 for _ in 0..outputs_to_watch_len {
2734 let txid = Readable::read(reader)?;
2735 let outputs_len: u64 = Readable::read(reader)?;
2736 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / (mem::size_of::<u32>() + mem::size_of::<Script>())));
2737 for _ in 0..outputs_len {
2738 outputs.push((Readable::read(reader)?, Readable::read(reader)?));
2740 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
2741 return Err(DecodeError::InvalidValue);
2744 let onchain_tx_handler = ReadableArgs::read(reader, keys_manager)?;
2746 let lockdown_from_offchain = Readable::read(reader)?;
2747 let holder_tx_signed = Readable::read(reader)?;
2749 let mut secp_ctx = Secp256k1::new();
2750 secp_ctx.seeded_randomize(&keys_manager.get_secure_random_bytes());
2752 Ok((last_block_hash.clone(), ChannelMonitor {
2753 inner: Mutex::new(ChannelMonitorImpl {
2755 commitment_transaction_number_obscure_factor,
2758 broadcasted_holder_revokable_script,
2759 counterparty_payment_script,
2763 holder_revocation_basepoint,
2765 current_counterparty_commitment_txid,
2766 prev_counterparty_commitment_txid,
2768 counterparty_tx_cache,
2769 funding_redeemscript,
2770 channel_value_satoshis,
2771 their_cur_revocation_points,
2776 counterparty_claimable_outpoints,
2777 counterparty_commitment_txn_on_chain,
2778 counterparty_hash_commitment_number,
2780 prev_holder_signed_commitment_tx,
2781 current_holder_commitment_tx,
2782 current_counterparty_commitment_number,
2783 current_holder_commitment_number,
2786 pending_monitor_events,
2789 onchain_events_waiting_threshold_conf,
2794 lockdown_from_offchain,
2806 use bitcoin::blockdata::constants::genesis_block;
2807 use bitcoin::blockdata::script::{Script, Builder};
2808 use bitcoin::blockdata::opcodes;
2809 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, SigHashType};
2810 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
2811 use bitcoin::util::bip143;
2812 use bitcoin::hashes::Hash;
2813 use bitcoin::hashes::sha256::Hash as Sha256;
2814 use bitcoin::hashes::hex::FromHex;
2815 use bitcoin::hash_types::Txid;
2816 use bitcoin::network::constants::Network;
2818 use chain::channelmonitor::ChannelMonitor;
2819 use chain::transaction::OutPoint;
2820 use ln::channelmanager::{PaymentPreimage, PaymentHash};
2821 use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
2823 use ln::chan_utils::{HTLCOutputInCommitment, ChannelPublicKeys, ChannelTransactionParameters, HolderCommitmentTransaction, CounterpartyChannelTransactionParameters};
2824 use util::test_utils::{TestLogger, TestBroadcaster, TestFeeEstimator};
2825 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
2826 use bitcoin::secp256k1::Secp256k1;
2827 use std::sync::{Arc, Mutex};
2828 use chain::keysinterface::InMemorySigner;
2831 fn test_prune_preimages() {
2832 let secp_ctx = Secp256k1::new();
2833 let logger = Arc::new(TestLogger::new());
2834 let broadcaster = Arc::new(TestBroadcaster{txn_broadcasted: Mutex::new(Vec::new())});
2835 let fee_estimator = Arc::new(TestFeeEstimator { sat_per_kw: 253 });
2837 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
2838 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2840 let mut preimages = Vec::new();
2843 let preimage = PaymentPreimage([i; 32]);
2844 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2845 preimages.push((preimage, hash));
2849 macro_rules! preimages_slice_to_htlc_outputs {
2850 ($preimages_slice: expr) => {
2852 let mut res = Vec::new();
2853 for (idx, preimage) in $preimages_slice.iter().enumerate() {
2854 res.push((HTLCOutputInCommitment {
2858 payment_hash: preimage.1.clone(),
2859 transaction_output_index: Some(idx as u32),
2866 macro_rules! preimages_to_holder_htlcs {
2867 ($preimages_slice: expr) => {
2869 let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2870 let res: Vec<_> = inp.drain(..).map(|e| { (e.0, None, e.1) }).collect();
2876 macro_rules! test_preimages_exist {
2877 ($preimages_slice: expr, $monitor: expr) => {
2878 for preimage in $preimages_slice {
2879 assert!($monitor.inner.lock().unwrap().payment_preimages.contains_key(&preimage.1));
2884 let keys = InMemorySigner::new(
2886 SecretKey::from_slice(&[41; 32]).unwrap(),
2887 SecretKey::from_slice(&[41; 32]).unwrap(),
2888 SecretKey::from_slice(&[41; 32]).unwrap(),
2889 SecretKey::from_slice(&[41; 32]).unwrap(),
2890 SecretKey::from_slice(&[41; 32]).unwrap(),
2896 let counterparty_pubkeys = ChannelPublicKeys {
2897 funding_pubkey: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
2898 revocation_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
2899 payment_point: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[46; 32]).unwrap()),
2900 delayed_payment_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[47; 32]).unwrap()),
2901 htlc_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[48; 32]).unwrap())
2903 let funding_outpoint = OutPoint { txid: Default::default(), index: u16::max_value() };
2904 let channel_parameters = ChannelTransactionParameters {
2905 holder_pubkeys: keys.holder_channel_pubkeys.clone(),
2906 holder_selected_contest_delay: 66,
2907 is_outbound_from_holder: true,
2908 counterparty_parameters: Some(CounterpartyChannelTransactionParameters {
2909 pubkeys: counterparty_pubkeys,
2910 selected_contest_delay: 67,
2912 funding_outpoint: Some(funding_outpoint),
2914 // Prune with one old state and a holder commitment tx holding a few overlaps with the
2916 let last_block_hash = genesis_block(Network::Testnet).block_hash();
2917 let monitor = ChannelMonitor::new(Secp256k1::new(), keys,
2918 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()), 0, &Script::new(),
2919 (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
2920 &channel_parameters,
2921 Script::new(), 46, 0,
2922 HolderCommitmentTransaction::dummy(), last_block_hash);
2924 monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..10])).unwrap();
2925 let dummy_txid = dummy_tx.txid();
2926 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
2927 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
2928 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
2929 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
2930 for &(ref preimage, ref hash) in preimages.iter() {
2931 monitor.provide_payment_preimage(hash, preimage, &broadcaster, &fee_estimator, &logger);
2934 // Now provide a secret, pruning preimages 10-15
2935 let mut secret = [0; 32];
2936 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2937 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2938 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 15);
2939 test_preimages_exist!(&preimages[0..10], monitor);
2940 test_preimages_exist!(&preimages[15..20], monitor);
2942 // Now provide a further secret, pruning preimages 15-17
2943 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2944 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2945 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 13);
2946 test_preimages_exist!(&preimages[0..10], monitor);
2947 test_preimages_exist!(&preimages[17..20], monitor);
2949 // Now update holder commitment tx info, pruning only element 18 as we still care about the
2950 // previous commitment tx's preimages too
2951 monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..5])).unwrap();
2952 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2953 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2954 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 12);
2955 test_preimages_exist!(&preimages[0..10], monitor);
2956 test_preimages_exist!(&preimages[18..20], monitor);
2958 // But if we do it again, we'll prune 5-10
2959 monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..3])).unwrap();
2960 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2961 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2962 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 5);
2963 test_preimages_exist!(&preimages[0..5], monitor);
2967 fn test_claim_txn_weight_computation() {
2968 // We test Claim txn weight, knowing that we want expected weigth and
2969 // not actual case to avoid sigs and time-lock delays hell variances.
2971 let secp_ctx = Secp256k1::new();
2972 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
2973 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
2974 let mut sum_actual_sigs = 0;
2976 macro_rules! sign_input {
2977 ($sighash_parts: expr, $idx: expr, $amount: expr, $input_type: expr, $sum_actual_sigs: expr) => {
2978 let htlc = HTLCOutputInCommitment {
2979 offered: if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::OfferedHTLC { true } else { false },
2981 cltv_expiry: 2 << 16,
2982 payment_hash: PaymentHash([1; 32]),
2983 transaction_output_index: Some($idx as u32),
2985 let redeem_script = if *$input_type == InputDescriptors::RevokedOutput { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &pubkey, &pubkey, &pubkey) };
2986 let sighash = hash_to_message!(&$sighash_parts.signature_hash($idx, &redeem_script, $amount, SigHashType::All)[..]);
2987 let sig = secp_ctx.sign(&sighash, &privkey);
2988 $sighash_parts.access_witness($idx).push(sig.serialize_der().to_vec());
2989 $sighash_parts.access_witness($idx)[0].push(SigHashType::All as u8);
2990 sum_actual_sigs += $sighash_parts.access_witness($idx)[0].len();
2991 if *$input_type == InputDescriptors::RevokedOutput {
2992 $sighash_parts.access_witness($idx).push(vec!(1));
2993 } else if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::RevokedReceivedHTLC {
2994 $sighash_parts.access_witness($idx).push(pubkey.clone().serialize().to_vec());
2995 } else if *$input_type == InputDescriptors::ReceivedHTLC {
2996 $sighash_parts.access_witness($idx).push(vec![0]);
2998 $sighash_parts.access_witness($idx).push(PaymentPreimage([1; 32]).0.to_vec());
3000 $sighash_parts.access_witness($idx).push(redeem_script.into_bytes());
3001 println!("witness[0] {}", $sighash_parts.access_witness($idx)[0].len());
3002 println!("witness[1] {}", $sighash_parts.access_witness($idx)[1].len());
3003 println!("witness[2] {}", $sighash_parts.access_witness($idx)[2].len());
3007 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
3008 let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
3010 // Justice tx with 1 to_holder, 2 revoked offered HTLCs, 1 revoked received HTLCs
3011 let mut claim_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
3013 claim_tx.input.push(TxIn {
3014 previous_output: BitcoinOutPoint {
3018 script_sig: Script::new(),
3019 sequence: 0xfffffffd,
3020 witness: Vec::new(),
3023 claim_tx.output.push(TxOut {
3024 script_pubkey: script_pubkey.clone(),
3027 let base_weight = claim_tx.get_weight();
3028 let inputs_des = vec![InputDescriptors::RevokedOutput, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedReceivedHTLC];
3030 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
3031 for (idx, inp) in inputs_des.iter().enumerate() {
3032 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
3035 assert_eq!(base_weight + OnchainTxHandler::<InMemorySigner>::get_witnesses_weight(&inputs_des[..]), claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_des.len() - sum_actual_sigs));
3037 // Claim tx with 1 offered HTLCs, 3 received HTLCs
3038 claim_tx.input.clear();
3039 sum_actual_sigs = 0;
3041 claim_tx.input.push(TxIn {
3042 previous_output: BitcoinOutPoint {
3046 script_sig: Script::new(),
3047 sequence: 0xfffffffd,
3048 witness: Vec::new(),
3051 let base_weight = claim_tx.get_weight();
3052 let inputs_des = vec![InputDescriptors::OfferedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC];
3054 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
3055 for (idx, inp) in inputs_des.iter().enumerate() {
3056 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
3059 assert_eq!(base_weight + OnchainTxHandler::<InMemorySigner>::get_witnesses_weight(&inputs_des[..]), claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_des.len() - sum_actual_sigs));
3061 // Justice tx with 1 revoked HTLC-Success tx output
3062 claim_tx.input.clear();
3063 sum_actual_sigs = 0;
3064 claim_tx.input.push(TxIn {
3065 previous_output: BitcoinOutPoint {
3069 script_sig: Script::new(),
3070 sequence: 0xfffffffd,
3071 witness: Vec::new(),
3073 let base_weight = claim_tx.get_weight();
3074 let inputs_des = vec![InputDescriptors::RevokedOutput];
3076 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
3077 for (idx, inp) in inputs_des.iter().enumerate() {
3078 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
3081 assert_eq!(base_weight + OnchainTxHandler::<InMemorySigner>::get_witnesses_weight(&inputs_des[..]), claim_tx.get_weight() + /* max_length_isg */ (73 * inputs_des.len() - sum_actual_sigs));
3084 // Further testing is done in the ChannelManager integration tests.