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 ManyChannelMonitor 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 latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date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 use bitcoin::blockdata::block::BlockHeader;
24 use bitcoin::blockdata::transaction::{TxOut,Transaction};
25 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
26 use bitcoin::blockdata::script::{Script, Builder};
27 use bitcoin::blockdata::opcodes;
28 use bitcoin::consensus::encode;
30 use bitcoin::hashes::Hash;
31 use bitcoin::hashes::sha256::Hash as Sha256;
32 use bitcoin::hash_types::{Txid, BlockHash, WPubkeyHash};
34 use bitcoin::secp256k1::{Secp256k1,Signature};
35 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
36 use bitcoin::secp256k1;
38 use ln::msgs::DecodeError;
40 use ln::chan_utils::{CounterpartyCommitmentSecrets, HTLCOutputInCommitment, HolderCommitmentTransaction, HTLCType};
41 use ln::channelmanager::{HTLCSource, PaymentPreimage, PaymentHash};
42 use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
44 use chain::chaininterface::{ChainListener, ChainWatchInterface, ChainWatchedUtil, BroadcasterInterface, FeeEstimator};
45 use chain::transaction::OutPoint;
46 use chain::keysinterface::{SpendableOutputDescriptor, ChannelKeys};
47 use util::logger::Logger;
48 use util::ser::{Readable, MaybeReadable, Writer, Writeable, U48};
49 use util::{byte_utils, events};
50 use util::events::Event;
52 use std::collections::{HashMap, HashSet, hash_map};
54 use std::{hash,cmp, mem};
58 /// An update generated by the underlying Channel itself which contains some new information the
59 /// ChannelMonitor should be made aware of.
60 #[cfg_attr(test, derive(PartialEq))]
63 pub struct ChannelMonitorUpdate {
64 pub(super) updates: Vec<ChannelMonitorUpdateStep>,
65 /// The sequence number of this update. Updates *must* be replayed in-order according to this
66 /// sequence number (and updates may panic if they are not). The update_id values are strictly
67 /// increasing and increase by one for each new update.
69 /// This sequence number is also used to track up to which points updates which returned
70 /// ChannelMonitorUpdateErr::TemporaryFailure have been applied to all copies of a given
71 /// ChannelMonitor when ChannelManager::channel_monitor_updated is called.
75 impl Writeable for ChannelMonitorUpdate {
76 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
77 self.update_id.write(w)?;
78 (self.updates.len() as u64).write(w)?;
79 for update_step in self.updates.iter() {
80 update_step.write(w)?;
85 impl Readable for ChannelMonitorUpdate {
86 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
87 let update_id: u64 = Readable::read(r)?;
88 let len: u64 = Readable::read(r)?;
89 let mut updates = Vec::with_capacity(cmp::min(len as usize, MAX_ALLOC_SIZE / ::std::mem::size_of::<ChannelMonitorUpdateStep>()));
91 updates.push(Readable::read(r)?);
93 Ok(Self { update_id, updates })
97 /// An error enum representing a failure to persist a channel monitor update.
99 pub enum ChannelMonitorUpdateErr {
100 /// Used to indicate a temporary failure (eg connection to a watchtower or remote backup of
101 /// our state failed, but is expected to succeed at some point in the future).
103 /// Such a failure will "freeze" a channel, preventing us from revoking old states or
104 /// submitting new commitment transactions to the counterparty. Once the update(s) which failed
105 /// have been successfully applied, ChannelManager::channel_monitor_updated can be used to
106 /// restore the channel to an operational state.
108 /// Note that a given ChannelManager will *never* re-generate a given ChannelMonitorUpdate. If
109 /// you return a TemporaryFailure you must ensure that it is written to disk safely before
110 /// writing out the latest ChannelManager state.
112 /// Even when a channel has been "frozen" updates to the ChannelMonitor can continue to occur
113 /// (eg if an inbound HTLC which we forwarded was claimed upstream resulting in us attempting
114 /// to claim it on this channel) and those updates must be applied wherever they can be. At
115 /// least one such updated ChannelMonitor must be persisted otherwise PermanentFailure should
116 /// be returned to get things on-chain ASAP using only the in-memory copy. Obviously updates to
117 /// the channel which would invalidate previous ChannelMonitors are not made when a channel has
120 /// Note that even if updates made after TemporaryFailure succeed you must still call
121 /// channel_monitor_updated to ensure you have the latest monitor and re-enable normal channel
124 /// Note that the update being processed here will not be replayed for you when you call
125 /// ChannelManager::channel_monitor_updated, so you must store the update itself along
126 /// with the persisted ChannelMonitor on your own local disk prior to returning a
127 /// TemporaryFailure. You may, of course, employ a journaling approach, storing only the
128 /// ChannelMonitorUpdate on disk without updating the monitor itself, replaying the journal at
131 /// For deployments where a copy of ChannelMonitors and other local state are backed up in a
132 /// remote location (with local copies persisted immediately), it is anticipated that all
133 /// updates will return TemporaryFailure until the remote copies could be updated.
135 /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
136 /// different watchtower and cannot update with all watchtowers that were previously informed
137 /// of this channel).
139 /// At reception of this error, ChannelManager will force-close the channel and return at
140 /// least a final ChannelMonitorUpdate::ChannelForceClosed which must be delivered to at
141 /// least one ChannelMonitor copy. Revocation secret MUST NOT be released and offchain channel
142 /// update must be rejected.
144 /// This failure may also signal a failure to update the local persisted copy of one of
145 /// the channel monitor instance.
147 /// Note that even when you fail a holder commitment transaction update, you must store the
148 /// update to ensure you can claim from it in case of a duplicate copy of this ChannelMonitor
149 /// broadcasts it (e.g distributed channel-monitor deployment)
153 /// General Err type for ChannelMonitor actions. Generally, this implies that the data provided is
154 /// inconsistent with the ChannelMonitor being called. eg for ChannelMonitor::update_monitor this
155 /// means you tried to update a monitor for a different channel or the ChannelMonitorUpdate was
157 /// Contains a human-readable error message.
159 pub struct MonitorUpdateError(pub &'static str);
161 /// An event to be processed by the ChannelManager.
163 pub enum MonitorEvent {
164 /// A monitor event containing an HTLCUpdate.
165 HTLCEvent(HTLCUpdate),
167 /// A monitor event that the Channel's commitment transaction was broadcasted.
168 CommitmentTxBroadcasted(OutPoint),
171 /// Simple structure send back by ManyChannelMonitor in case of HTLC detected onchain from a
172 /// forward channel and from which info are needed to update HTLC in a backward channel.
173 #[derive(Clone, PartialEq)]
174 pub struct HTLCUpdate {
175 pub(super) payment_hash: PaymentHash,
176 pub(super) payment_preimage: Option<PaymentPreimage>,
177 pub(super) source: HTLCSource
179 impl_writeable!(HTLCUpdate, 0, { payment_hash, payment_preimage, source });
181 /// A simple implementation of a ManyChannelMonitor and ChainListener. Can be used to create a
182 /// watchtower or watch our own channels.
184 /// Note that you must provide your own key by which to refer to channels.
186 /// If you're accepting remote monitors (ie are implementing a watchtower), you must verify that
187 /// users cannot overwrite a given channel by providing a duplicate key. ie you should probably
188 /// index by a PublicKey which is required to sign any updates.
190 /// If you're using this for local monitoring of your own channels, you probably want to use
191 /// `OutPoint` as the key, which will give you a ManyChannelMonitor implementation.
193 /// (C-not exported) due to an unconstrained generic in `Key`
194 pub struct SimpleManyChannelMonitor<Key, ChanSigner: ChannelKeys, T: Deref, F: Deref, L: Deref, C: Deref>
195 where T::Target: BroadcasterInterface,
196 F::Target: FeeEstimator,
198 C::Target: ChainWatchInterface,
201 pub monitors: Mutex<HashMap<Key, ChannelMonitor<ChanSigner>>>,
202 watch_events: Mutex<WatchEventQueue>,
209 struct WatchEventQueue {
210 watched: ChainWatchedUtil,
211 events: Vec<chain::WatchEvent>,
214 impl WatchEventQueue {
217 watched: ChainWatchedUtil::new(),
222 fn watch_tx(&mut self, txid: &Txid, script_pubkey: &Script) {
223 if self.watched.register_tx(txid, script_pubkey) {
224 self.events.push(chain::WatchEvent::WatchTransaction {
226 script_pubkey: script_pubkey.clone()
231 fn watch_output(&mut self, outpoint: (&Txid, usize), script_pubkey: &Script) {
232 let (txid, index) = outpoint;
233 if self.watched.register_outpoint((*txid, index as u32), script_pubkey) {
234 self.events.push(chain::WatchEvent::WatchOutput {
239 script_pubkey: script_pubkey.clone(),
244 fn dequeue_events(&mut self) -> Vec<chain::WatchEvent> {
245 let mut pending_events = Vec::with_capacity(self.events.len());
246 pending_events.append(&mut self.events);
250 fn filter_block<'a>(&self, txdata: &[(usize, &'a Transaction)]) -> Vec<(usize, &'a Transaction)> {
251 let mut matched_txids = HashSet::new();
252 txdata.iter().filter(|&&(_, tx)| {
253 // A tx matches the filter if it either matches the filter directly (via does_match_tx)
254 // or if it is a descendant of another matched transaction within the same block.
255 let mut matched = self.watched.does_match_tx(tx);
256 for input in tx.input.iter() {
257 if matched || matched_txids.contains(&input.previous_output.txid) {
263 matched_txids.insert(tx.txid());
266 }).map(|e| *e).collect()
270 impl<Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys, T: Deref + Sync + Send, F: Deref + Sync + Send, L: Deref + Sync + Send, C: Deref + Sync + Send>
271 ChainListener for SimpleManyChannelMonitor<Key, ChanSigner, T, F, L, C>
272 where T::Target: BroadcasterInterface,
273 F::Target: FeeEstimator,
275 C::Target: ChainWatchInterface,
277 fn block_connected(&self, header: &BlockHeader, txdata: &[(usize, &Transaction)], height: u32) {
278 let mut watch_events = self.watch_events.lock().unwrap();
279 let matched_txn = watch_events.filter_block(txdata);
281 let mut monitors = self.monitors.lock().unwrap();
282 for monitor in monitors.values_mut() {
283 let txn_outputs = monitor.block_connected(header, &matched_txn, height, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
285 for (ref txid, ref outputs) in txn_outputs {
286 for (idx, output) in outputs.iter().enumerate() {
287 watch_events.watch_output((txid, idx), &output.script_pubkey);
294 fn block_disconnected(&self, header: &BlockHeader, disconnected_height: u32) {
295 let mut monitors = self.monitors.lock().unwrap();
296 for monitor in monitors.values_mut() {
297 monitor.block_disconnected(header, disconnected_height, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
302 impl<Key : Send + cmp::Eq + hash::Hash + 'static, ChanSigner: ChannelKeys, T: Deref, F: Deref, L: Deref, C: Deref> SimpleManyChannelMonitor<Key, ChanSigner, T, F, L, C>
303 where T::Target: BroadcasterInterface,
304 F::Target: FeeEstimator,
306 C::Target: ChainWatchInterface,
308 /// Creates a new object which can be used to monitor several channels given the chain
309 /// interface with which to register to receive notifications.
310 pub fn new(chain_monitor: C, broadcaster: T, logger: L, feeest: F) -> SimpleManyChannelMonitor<Key, ChanSigner, T, F, L, C> {
311 let res = SimpleManyChannelMonitor {
312 monitors: Mutex::new(HashMap::new()),
313 watch_events: Mutex::new(WatchEventQueue::new()),
317 fee_estimator: feeest,
323 /// Adds or updates the monitor which monitors the channel referred to by the given key.
324 pub fn add_monitor_by_key(&self, key: Key, monitor: ChannelMonitor<ChanSigner>) -> Result<(), MonitorUpdateError> {
325 let mut watch_events = self.watch_events.lock().unwrap();
326 let mut monitors = self.monitors.lock().unwrap();
327 let entry = match monitors.entry(key) {
328 hash_map::Entry::Occupied(_) => return Err(MonitorUpdateError("Channel monitor for given key is already present")),
329 hash_map::Entry::Vacant(e) => e,
332 let funding_txo = monitor.get_funding_txo();
333 log_trace!(self.logger, "Got new Channel Monitor for channel {}", log_bytes!(funding_txo.0.to_channel_id()[..]));
334 watch_events.watch_tx(&funding_txo.0.txid, &funding_txo.1);
335 watch_events.watch_output((&funding_txo.0.txid, funding_txo.0.index as usize), &funding_txo.1);
336 for (txid, outputs) in monitor.get_outputs_to_watch().iter() {
337 for (idx, script) in outputs.iter().enumerate() {
338 watch_events.watch_output((txid, idx), script);
342 entry.insert(monitor);
346 /// Updates the monitor which monitors the channel referred to by the given key.
347 pub fn update_monitor_by_key(&self, key: Key, update: ChannelMonitorUpdate) -> Result<(), MonitorUpdateError> {
348 let mut monitors = self.monitors.lock().unwrap();
349 match monitors.get_mut(&key) {
350 Some(orig_monitor) => {
351 log_trace!(self.logger, "Updating Channel Monitor for channel {}", log_funding_info!(orig_monitor));
352 orig_monitor.update_monitor(update, &self.broadcaster, &self.logger)
354 None => Err(MonitorUpdateError("No such monitor registered"))
359 impl<ChanSigner: ChannelKeys, T: Deref + Sync + Send, F: Deref + Sync + Send, L: Deref + Sync + Send, C: Deref + Sync + Send> ManyChannelMonitor for SimpleManyChannelMonitor<OutPoint, ChanSigner, T, F, L, C>
360 where T::Target: BroadcasterInterface,
361 F::Target: FeeEstimator,
363 C::Target: ChainWatchInterface,
365 type Keys = ChanSigner;
367 fn add_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor<ChanSigner>) -> Result<(), ChannelMonitorUpdateErr> {
368 match self.add_monitor_by_key(funding_txo, monitor) {
370 Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
374 fn update_monitor(&self, funding_txo: OutPoint, update: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr> {
375 match self.update_monitor_by_key(funding_txo, update) {
377 Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
381 fn get_and_clear_pending_monitor_events(&self) -> Vec<MonitorEvent> {
382 let mut pending_monitor_events = Vec::new();
383 for chan in self.monitors.lock().unwrap().values_mut() {
384 pending_monitor_events.append(&mut chan.get_and_clear_pending_monitor_events());
386 pending_monitor_events
390 impl<Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys, T: Deref, F: Deref, L: Deref, C: Deref> events::EventsProvider for SimpleManyChannelMonitor<Key, ChanSigner, T, F, L, C>
391 where T::Target: BroadcasterInterface,
392 F::Target: FeeEstimator,
394 C::Target: ChainWatchInterface,
396 fn get_and_clear_pending_events(&self) -> Vec<Event> {
397 let mut pending_events = Vec::new();
398 for chan in self.monitors.lock().unwrap().values_mut() {
399 pending_events.append(&mut chan.get_and_clear_pending_events());
405 impl<Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys, T: Deref, F: Deref, L: Deref, C: Deref> chain::WatchEventProvider for SimpleManyChannelMonitor<Key, ChanSigner, T, F, L, C>
406 where T::Target: BroadcasterInterface,
407 F::Target: FeeEstimator,
409 C::Target: ChainWatchInterface,
411 fn release_pending_watch_events(&self) -> Vec<chain::WatchEvent> {
412 self.watch_events.lock().unwrap().dequeue_events()
416 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
417 /// instead claiming it in its own individual transaction.
418 pub(crate) const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
419 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
420 /// HTLC-Success transaction.
421 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
422 /// transaction confirmed (and we use it in a few more, equivalent, places).
423 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 6;
424 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
425 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
426 /// copies of ChannelMonitors, including watchtowers). We could enforce the contract by failing
427 /// at CLTV expiration height but giving a grace period to our peer may be profitable for us if he
428 /// can provide an over-late preimage. Nevertheless, grace period has to be accounted in our
429 /// CLTV_EXPIRY_DELTA to be secure. Following this policy we may decrease the rate of channel failures
430 /// due to expiration but increase the cost of funds being locked longuer in case of failure.
431 /// This delay also cover a low-power peer being slow to process blocks and so being behind us on
432 /// accurate block height.
433 /// In case of onchain failure to be pass backward we may see the last block of ANTI_REORG_DELAY
434 /// with at worst this delay, so we are not only using this value as a mercy for them but also
435 /// us as a safeguard to delay with enough time.
436 pub(crate) const LATENCY_GRACE_PERIOD_BLOCKS: u32 = 3;
437 /// Number of blocks we wait on seeing a HTLC output being solved before we fail corresponding inbound
438 /// HTLCs. This prevents us from failing backwards and then getting a reorg resulting in us losing money.
439 /// We use also this delay to be sure we can remove our in-flight claim txn from bump candidates buffer.
440 /// It may cause spurrious generation of bumped claim txn but that's allright given the outpoint is already
441 /// solved by a previous claim tx. What we want to avoid is reorg evicting our claim tx and us not
442 /// keeping bumping another claim tx to solve the outpoint.
443 pub(crate) const ANTI_REORG_DELAY: u32 = 6;
444 /// Number of blocks before confirmation at which we fail back an un-relayed HTLC or at which we
445 /// refuse to accept a new HTLC.
447 /// This is used for a few separate purposes:
448 /// 1) if we've received an MPP HTLC to us and it expires within this many blocks and we are
449 /// waiting on additional parts (or waiting on the preimage for any HTLC from the user), we will
451 /// 2) if we receive an HTLC within this many blocks of its expiry (plus one to avoid a race
452 /// condition with the above), we will fail this HTLC without telling the user we received it,
453 /// 3) if we are waiting on a connection or a channel state update to send an HTLC to a peer, and
454 /// that HTLC expires within this many blocks, we will simply fail the HTLC instead.
456 /// (1) is all about protecting us - we need enough time to update the channel state before we hit
457 /// CLTV_CLAIM_BUFFER, at which point we'd go on chain to claim the HTLC with the preimage.
459 /// (2) is the same, but with an additional buffer to avoid accepting an HTLC which is immediately
460 /// in a race condition between the user connecting a block (which would fail it) and the user
461 /// providing us the preimage (which would claim it).
463 /// (3) is about our counterparty - we don't want to relay an HTLC to a counterparty when they may
464 /// end up force-closing the channel on us to claim it.
465 pub(crate) const HTLC_FAIL_BACK_BUFFER: u32 = CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS;
467 #[derive(Clone, PartialEq)]
468 struct HolderSignedTx {
469 /// txid of the transaction in tx, just used to make comparison faster
471 revocation_key: PublicKey,
472 a_htlc_key: PublicKey,
473 b_htlc_key: PublicKey,
474 delayed_payment_key: PublicKey,
475 per_commitment_point: PublicKey,
477 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
480 /// We use this to track counterparty commitment transactions and htlcs outputs and
481 /// use it to generate any justice or 2nd-stage preimage/timeout transactions.
483 struct CounterpartyCommitmentTransaction {
484 counterparty_delayed_payment_base_key: PublicKey,
485 counterparty_htlc_base_key: PublicKey,
486 on_counterparty_tx_csv: u16,
487 per_htlc: HashMap<Txid, Vec<HTLCOutputInCommitment>>
490 impl Writeable for CounterpartyCommitmentTransaction {
491 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
492 self.counterparty_delayed_payment_base_key.write(w)?;
493 self.counterparty_htlc_base_key.write(w)?;
494 w.write_all(&byte_utils::be16_to_array(self.on_counterparty_tx_csv))?;
495 w.write_all(&byte_utils::be64_to_array(self.per_htlc.len() as u64))?;
496 for (ref txid, ref htlcs) in self.per_htlc.iter() {
497 w.write_all(&txid[..])?;
498 w.write_all(&byte_utils::be64_to_array(htlcs.len() as u64))?;
499 for &ref htlc in htlcs.iter() {
506 impl Readable for CounterpartyCommitmentTransaction {
507 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
508 let counterparty_commitment_transaction = {
509 let counterparty_delayed_payment_base_key = Readable::read(r)?;
510 let counterparty_htlc_base_key = Readable::read(r)?;
511 let on_counterparty_tx_csv: u16 = Readable::read(r)?;
512 let per_htlc_len: u64 = Readable::read(r)?;
513 let mut per_htlc = HashMap::with_capacity(cmp::min(per_htlc_len as usize, MAX_ALLOC_SIZE / 64));
514 for _ in 0..per_htlc_len {
515 let txid: Txid = Readable::read(r)?;
516 let htlcs_count: u64 = Readable::read(r)?;
517 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
518 for _ in 0..htlcs_count {
519 let htlc = Readable::read(r)?;
522 if let Some(_) = per_htlc.insert(txid, htlcs) {
523 return Err(DecodeError::InvalidValue);
526 CounterpartyCommitmentTransaction {
527 counterparty_delayed_payment_base_key,
528 counterparty_htlc_base_key,
529 on_counterparty_tx_csv,
533 Ok(counterparty_commitment_transaction)
537 /// When ChannelMonitor discovers an onchain outpoint being a step of a channel and that it needs
538 /// to generate a tx to push channel state forward, we cache outpoint-solving tx material to build
539 /// a new bumped one in case of lenghty confirmation delay
540 #[derive(Clone, PartialEq)]
541 pub(crate) enum InputMaterial {
543 per_commitment_point: PublicKey,
544 counterparty_delayed_payment_base_key: PublicKey,
545 counterparty_htlc_base_key: PublicKey,
546 per_commitment_key: SecretKey,
547 input_descriptor: InputDescriptors,
549 htlc: Option<HTLCOutputInCommitment>,
550 on_counterparty_tx_csv: u16,
553 per_commitment_point: PublicKey,
554 counterparty_delayed_payment_base_key: PublicKey,
555 counterparty_htlc_base_key: PublicKey,
556 preimage: Option<PaymentPreimage>,
557 htlc: HTLCOutputInCommitment
560 preimage: Option<PaymentPreimage>,
564 funding_redeemscript: Script,
568 impl Writeable for InputMaterial {
569 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
571 &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} => {
572 writer.write_all(&[0; 1])?;
573 per_commitment_point.write(writer)?;
574 counterparty_delayed_payment_base_key.write(writer)?;
575 counterparty_htlc_base_key.write(writer)?;
576 writer.write_all(&per_commitment_key[..])?;
577 input_descriptor.write(writer)?;
578 writer.write_all(&byte_utils::be64_to_array(*amount))?;
580 on_counterparty_tx_csv.write(writer)?;
582 &InputMaterial::CounterpartyHTLC { ref per_commitment_point, ref counterparty_delayed_payment_base_key, ref counterparty_htlc_base_key, ref preimage, ref htlc} => {
583 writer.write_all(&[1; 1])?;
584 per_commitment_point.write(writer)?;
585 counterparty_delayed_payment_base_key.write(writer)?;
586 counterparty_htlc_base_key.write(writer)?;
587 preimage.write(writer)?;
590 &InputMaterial::HolderHTLC { ref preimage, ref amount } => {
591 writer.write_all(&[2; 1])?;
592 preimage.write(writer)?;
593 writer.write_all(&byte_utils::be64_to_array(*amount))?;
595 &InputMaterial::Funding { ref funding_redeemscript } => {
596 writer.write_all(&[3; 1])?;
597 funding_redeemscript.write(writer)?;
604 impl Readable for InputMaterial {
605 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
606 let input_material = match <u8 as Readable>::read(reader)? {
608 let per_commitment_point = Readable::read(reader)?;
609 let counterparty_delayed_payment_base_key = Readable::read(reader)?;
610 let counterparty_htlc_base_key = Readable::read(reader)?;
611 let per_commitment_key = Readable::read(reader)?;
612 let input_descriptor = Readable::read(reader)?;
613 let amount = Readable::read(reader)?;
614 let htlc = Readable::read(reader)?;
615 let on_counterparty_tx_csv = Readable::read(reader)?;
616 InputMaterial::Revoked {
617 per_commitment_point,
618 counterparty_delayed_payment_base_key,
619 counterparty_htlc_base_key,
624 on_counterparty_tx_csv
628 let per_commitment_point = Readable::read(reader)?;
629 let counterparty_delayed_payment_base_key = Readable::read(reader)?;
630 let counterparty_htlc_base_key = Readable::read(reader)?;
631 let preimage = Readable::read(reader)?;
632 let htlc = Readable::read(reader)?;
633 InputMaterial::CounterpartyHTLC {
634 per_commitment_point,
635 counterparty_delayed_payment_base_key,
636 counterparty_htlc_base_key,
642 let preimage = Readable::read(reader)?;
643 let amount = Readable::read(reader)?;
644 InputMaterial::HolderHTLC {
650 InputMaterial::Funding {
651 funding_redeemscript: Readable::read(reader)?,
654 _ => return Err(DecodeError::InvalidValue),
660 /// ClaimRequest is a descriptor structure to communicate between detection
661 /// and reaction module. They are generated by ChannelMonitor while parsing
662 /// onchain txn leaked from a channel and handed over to OnchainTxHandler which
663 /// is responsible for opportunistic aggregation, selecting and enforcing
664 /// bumping logic, building and signing transactions.
665 pub(crate) struct ClaimRequest {
666 // Block height before which claiming is exclusive to one party,
667 // after reaching it, claiming may be contentious.
668 pub(crate) absolute_timelock: u32,
669 // Timeout tx must have nLocktime set which means aggregating multiple
670 // ones must take the higher nLocktime among them to satisfy all of them.
671 // Sadly it has few pitfalls, a) it takes longuer to get fund back b) CLTV_DELTA
672 // of a sooner-HTLC could be swallowed by the highest nLocktime of the HTLC set.
673 // Do simplify we mark them as non-aggregable.
674 pub(crate) aggregable: bool,
675 // Basic bitcoin outpoint (txid, vout)
676 pub(crate) outpoint: BitcoinOutPoint,
677 // Following outpoint type, set of data needed to generate transaction digest
678 // and satisfy witness program.
679 pub(crate) witness_data: InputMaterial
682 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
683 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
684 #[derive(Clone, PartialEq)]
686 /// HTLC output getting solved by a timeout, at maturation we pass upstream payment source information to solve
687 /// inbound HTLC in backward channel. Note, in case of preimage, we pass info to upstream without delay as we can
688 /// only win from it, so it's never an OnchainEvent
690 htlc_update: (HTLCSource, PaymentHash),
693 descriptor: SpendableOutputDescriptor,
697 const SERIALIZATION_VERSION: u8 = 1;
698 const MIN_SERIALIZATION_VERSION: u8 = 1;
700 #[cfg_attr(test, derive(PartialEq))]
702 pub(super) enum ChannelMonitorUpdateStep {
703 LatestHolderCommitmentTXInfo {
704 commitment_tx: HolderCommitmentTransaction,
705 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
707 LatestCounterpartyCommitmentTXInfo {
708 unsigned_commitment_tx: Transaction, // TODO: We should actually only need the txid here
709 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
710 commitment_number: u64,
711 their_revocation_point: PublicKey,
714 payment_preimage: PaymentPreimage,
720 /// Used to indicate that the no future updates will occur, and likely that the latest holder
721 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
723 /// If set to false, we shouldn't broadcast the latest holder commitment transaction as we
724 /// think we've fallen behind!
725 should_broadcast: bool,
729 impl Writeable for ChannelMonitorUpdateStep {
730 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
732 &ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { ref commitment_tx, ref htlc_outputs } => {
734 commitment_tx.write(w)?;
735 (htlc_outputs.len() as u64).write(w)?;
736 for &(ref output, ref signature, ref source) in htlc_outputs.iter() {
742 &ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { ref unsigned_commitment_tx, ref htlc_outputs, ref commitment_number, ref their_revocation_point } => {
744 unsigned_commitment_tx.write(w)?;
745 commitment_number.write(w)?;
746 their_revocation_point.write(w)?;
747 (htlc_outputs.len() as u64).write(w)?;
748 for &(ref output, ref source) in htlc_outputs.iter() {
750 source.as_ref().map(|b| b.as_ref()).write(w)?;
753 &ChannelMonitorUpdateStep::PaymentPreimage { ref payment_preimage } => {
755 payment_preimage.write(w)?;
757 &ChannelMonitorUpdateStep::CommitmentSecret { ref idx, ref secret } => {
762 &ChannelMonitorUpdateStep::ChannelForceClosed { ref should_broadcast } => {
764 should_broadcast.write(w)?;
770 impl Readable for ChannelMonitorUpdateStep {
771 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
772 match Readable::read(r)? {
774 Ok(ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo {
775 commitment_tx: Readable::read(r)?,
777 let len: u64 = Readable::read(r)?;
778 let mut res = Vec::new();
780 res.push((Readable::read(r)?, Readable::read(r)?, Readable::read(r)?));
787 Ok(ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo {
788 unsigned_commitment_tx: Readable::read(r)?,
789 commitment_number: Readable::read(r)?,
790 their_revocation_point: Readable::read(r)?,
792 let len: u64 = Readable::read(r)?;
793 let mut res = Vec::new();
795 res.push((Readable::read(r)?, <Option<HTLCSource> as Readable>::read(r)?.map(|o| Box::new(o))));
802 Ok(ChannelMonitorUpdateStep::PaymentPreimage {
803 payment_preimage: Readable::read(r)?,
807 Ok(ChannelMonitorUpdateStep::CommitmentSecret {
808 idx: Readable::read(r)?,
809 secret: Readable::read(r)?,
813 Ok(ChannelMonitorUpdateStep::ChannelForceClosed {
814 should_broadcast: Readable::read(r)?
817 _ => Err(DecodeError::InvalidValue),
822 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
823 /// on-chain transactions to ensure no loss of funds occurs.
825 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
826 /// information and are actively monitoring the chain.
828 /// Pending Events or updated HTLCs which have not yet been read out by
829 /// get_and_clear_pending_monitor_events or get_and_clear_pending_events are serialized to disk and
830 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
831 /// gotten are fully handled before re-serializing the new state.
832 pub struct ChannelMonitor<ChanSigner: ChannelKeys> {
833 latest_update_id: u64,
834 commitment_transaction_number_obscure_factor: u64,
836 destination_script: Script,
837 broadcasted_holder_revokable_script: Option<(Script, PublicKey, PublicKey)>,
838 counterparty_payment_script: Script,
839 shutdown_script: Script,
842 funding_info: (OutPoint, Script),
843 current_counterparty_commitment_txid: Option<Txid>,
844 prev_counterparty_commitment_txid: Option<Txid>,
846 counterparty_tx_cache: CounterpartyCommitmentTransaction,
847 funding_redeemscript: Script,
848 channel_value_satoshis: u64,
849 // first is the idx of the first of the two revocation points
850 their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
852 on_holder_tx_csv: u16,
854 commitment_secrets: CounterpartyCommitmentSecrets,
855 counterparty_claimable_outpoints: HashMap<Txid, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
856 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
857 /// Nor can we figure out their commitment numbers without the commitment transaction they are
858 /// spending. Thus, in order to claim them via revocation key, we track all the counterparty
859 /// commitment transactions which we find on-chain, mapping them to the commitment number which
860 /// can be used to derive the revocation key and claim the transactions.
861 counterparty_commitment_txn_on_chain: HashMap<Txid, (u64, Vec<Script>)>,
862 /// Cache used to make pruning of payment_preimages faster.
863 /// Maps payment_hash values to commitment numbers for counterparty transactions for non-revoked
864 /// counterparty transactions (ie should remain pretty small).
865 /// Serialized to disk but should generally not be sent to Watchtowers.
866 counterparty_hash_commitment_number: HashMap<PaymentHash, u64>,
868 // We store two holder commitment transactions to avoid any race conditions where we may update
869 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
870 // various monitors for one channel being out of sync, and us broadcasting a holder
871 // transaction for which we have deleted claim information on some watchtowers.
872 prev_holder_signed_commitment_tx: Option<HolderSignedTx>,
873 current_holder_commitment_tx: HolderSignedTx,
875 // Used just for ChannelManager to make sure it has the latest channel data during
877 current_counterparty_commitment_number: u64,
878 // Used just for ChannelManager to make sure it has the latest channel data during
880 current_holder_commitment_number: u64,
882 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
884 pending_monitor_events: Vec<MonitorEvent>,
885 pending_events: Vec<Event>,
887 // Used to track onchain events, i.e transactions parts of channels confirmed on chain, on which
888 // we have to take actions once they reach enough confs. Key is a block height timer, i.e we enforce
889 // actions when we receive a block with given height. Actions depend on OnchainEvent type.
890 onchain_events_waiting_threshold_conf: HashMap<u32, Vec<OnchainEvent>>,
892 // If we get serialized out and re-read, we need to make sure that the chain monitoring
893 // interface knows about the TXOs that we want to be notified of spends of. We could probably
894 // be smart and derive them from the above storage fields, but its much simpler and more
895 // Obviously Correct (tm) if we just keep track of them explicitly.
896 outputs_to_watch: HashMap<Txid, Vec<Script>>,
899 pub onchain_tx_handler: OnchainTxHandler<ChanSigner>,
901 onchain_tx_handler: OnchainTxHandler<ChanSigner>,
903 // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
904 // channel has been force-closed. After this is set, no further holder commitment transaction
905 // updates may occur, and we panic!() if one is provided.
906 lockdown_from_offchain: bool,
908 // Set once we've signed a holder commitment transaction and handed it over to our
909 // OnchainTxHandler. After this is set, no future updates to our holder commitment transactions
910 // may occur, and we fail any such monitor updates.
912 // In case of update rejection due to a locally already signed commitment transaction, we
913 // nevertheless store update content to track in case of concurrent broadcast by another
914 // remote monitor out-of-order with regards to the block view.
915 holder_tx_signed: bool,
917 // We simply modify last_block_hash in Channel's block_connected so that serialization is
918 // consistent but hopefully the users' copy handles block_connected in a consistent way.
919 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
920 // their last_block_hash from its state and not based on updated copies that didn't run through
921 // the full block_connected).
922 last_block_hash: BlockHash,
923 secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
926 /// Simple trait indicating ability to track a set of ChannelMonitors and multiplex events between
927 /// them. Generally should be implemented by keeping a local SimpleManyChannelMonitor and passing
928 /// events to it, while also taking any add/update_monitor events and passing them to some remote
931 /// In general, you must always have at least one local copy in memory, which must never fail to
932 /// update (as it is responsible for broadcasting the latest state in case the channel is closed),
933 /// and then persist it to various on-disk locations. If, for some reason, the in-memory copy fails
934 /// to update (eg out-of-memory or some other condition), you must immediately shut down without
935 /// taking any further action such as writing the current state to disk. This should likely be
936 /// accomplished via panic!() or abort().
938 /// Note that any updates to a channel's monitor *must* be applied to each instance of the
939 /// channel's monitor everywhere (including remote watchtowers) *before* this function returns. If
940 /// an update occurs and a remote watchtower is left with old state, it may broadcast transactions
941 /// which we have revoked, allowing our counterparty to claim all funds in the channel!
943 /// User needs to notify implementors of ManyChannelMonitor when a new block is connected or
944 /// disconnected using their `block_connected` and `block_disconnected` methods. However, rather
945 /// than calling these methods directly, the user should register implementors as listeners to the
946 /// BlockNotifier and call the BlockNotifier's `block_(dis)connected` methods, which will notify
947 /// all registered listeners in one go.
948 pub trait ManyChannelMonitor: Send + Sync {
949 /// The concrete type which signs for transactions and provides access to our channel public
951 type Keys: ChannelKeys;
953 /// Adds a monitor for the given `funding_txo`.
955 /// Implementations must ensure that `monitor` receives block_connected calls for blocks with
956 /// the funding transaction or any spends of it, as well as any spends of outputs returned by
957 /// get_outputs_to_watch. Not doing so may result in LOST FUNDS.
958 fn add_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor<Self::Keys>) -> Result<(), ChannelMonitorUpdateErr>;
960 /// Updates a monitor for the given `funding_txo`.
962 /// TODO(jkczyz): Determine where this should go from e73036c6845fd3cc16479a1b497db82a5ebb3897.
964 /// In case of distributed watchtowers deployment, even if an Err is return, the new version
965 /// must be written to disk, as state may have been stored but rejected due to a block forcing
966 /// a commitment broadcast. This storage is used to claim outputs of rejected state confirmed
967 /// onchain by another watchtower, lagging behind on block processing.
968 fn update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr>;
970 /// Used by ChannelManager to get list of HTLC resolved onchain and which needed to be updated
971 /// with success or failure.
973 /// You should probably just call through to
974 /// ChannelMonitor::get_and_clear_pending_monitor_events() for each ChannelMonitor and return
976 fn get_and_clear_pending_monitor_events(&self) -> Vec<MonitorEvent>;
979 #[cfg(any(test, feature = "fuzztarget"))]
980 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
981 /// underlying object
982 impl<ChanSigner: ChannelKeys> PartialEq for ChannelMonitor<ChanSigner> {
983 fn eq(&self, other: &Self) -> bool {
984 if self.latest_update_id != other.latest_update_id ||
985 self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
986 self.destination_script != other.destination_script ||
987 self.broadcasted_holder_revokable_script != other.broadcasted_holder_revokable_script ||
988 self.counterparty_payment_script != other.counterparty_payment_script ||
989 self.keys.pubkeys() != other.keys.pubkeys() ||
990 self.funding_info != other.funding_info ||
991 self.current_counterparty_commitment_txid != other.current_counterparty_commitment_txid ||
992 self.prev_counterparty_commitment_txid != other.prev_counterparty_commitment_txid ||
993 self.counterparty_tx_cache != other.counterparty_tx_cache ||
994 self.funding_redeemscript != other.funding_redeemscript ||
995 self.channel_value_satoshis != other.channel_value_satoshis ||
996 self.their_cur_revocation_points != other.their_cur_revocation_points ||
997 self.on_holder_tx_csv != other.on_holder_tx_csv ||
998 self.commitment_secrets != other.commitment_secrets ||
999 self.counterparty_claimable_outpoints != other.counterparty_claimable_outpoints ||
1000 self.counterparty_commitment_txn_on_chain != other.counterparty_commitment_txn_on_chain ||
1001 self.counterparty_hash_commitment_number != other.counterparty_hash_commitment_number ||
1002 self.prev_holder_signed_commitment_tx != other.prev_holder_signed_commitment_tx ||
1003 self.current_counterparty_commitment_number != other.current_counterparty_commitment_number ||
1004 self.current_holder_commitment_number != other.current_holder_commitment_number ||
1005 self.current_holder_commitment_tx != other.current_holder_commitment_tx ||
1006 self.payment_preimages != other.payment_preimages ||
1007 self.pending_monitor_events != other.pending_monitor_events ||
1008 self.pending_events.len() != other.pending_events.len() || // We trust events to round-trip properly
1009 self.onchain_events_waiting_threshold_conf != other.onchain_events_waiting_threshold_conf ||
1010 self.outputs_to_watch != other.outputs_to_watch ||
1011 self.lockdown_from_offchain != other.lockdown_from_offchain ||
1012 self.holder_tx_signed != other.holder_tx_signed
1021 impl<ChanSigner: ChannelKeys + Writeable> ChannelMonitor<ChanSigner> {
1022 /// Writes this monitor into the given writer, suitable for writing to disk.
1024 /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
1025 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
1026 /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
1027 /// returned block hash and the the current chain and then reconnecting blocks to get to the
1028 /// best chain) upon deserializing the object!
1029 pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
1030 //TODO: We still write out all the serialization here manually instead of using the fancy
1031 //serialization framework we have, we should migrate things over to it.
1032 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
1033 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
1035 self.latest_update_id.write(writer)?;
1037 // Set in initial Channel-object creation, so should always be set by now:
1038 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
1040 self.destination_script.write(writer)?;
1041 if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
1042 writer.write_all(&[0; 1])?;
1043 broadcasted_holder_revokable_script.0.write(writer)?;
1044 broadcasted_holder_revokable_script.1.write(writer)?;
1045 broadcasted_holder_revokable_script.2.write(writer)?;
1047 writer.write_all(&[1; 1])?;
1050 self.counterparty_payment_script.write(writer)?;
1051 self.shutdown_script.write(writer)?;
1053 self.keys.write(writer)?;
1054 writer.write_all(&self.funding_info.0.txid[..])?;
1055 writer.write_all(&byte_utils::be16_to_array(self.funding_info.0.index))?;
1056 self.funding_info.1.write(writer)?;
1057 self.current_counterparty_commitment_txid.write(writer)?;
1058 self.prev_counterparty_commitment_txid.write(writer)?;
1060 self.counterparty_tx_cache.write(writer)?;
1061 self.funding_redeemscript.write(writer)?;
1062 self.channel_value_satoshis.write(writer)?;
1064 match self.their_cur_revocation_points {
1065 Some((idx, pubkey, second_option)) => {
1066 writer.write_all(&byte_utils::be48_to_array(idx))?;
1067 writer.write_all(&pubkey.serialize())?;
1068 match second_option {
1069 Some(second_pubkey) => {
1070 writer.write_all(&second_pubkey.serialize())?;
1073 writer.write_all(&[0; 33])?;
1078 writer.write_all(&byte_utils::be48_to_array(0))?;
1082 writer.write_all(&byte_utils::be16_to_array(self.on_holder_tx_csv))?;
1084 self.commitment_secrets.write(writer)?;
1086 macro_rules! serialize_htlc_in_commitment {
1087 ($htlc_output: expr) => {
1088 writer.write_all(&[$htlc_output.offered as u8; 1])?;
1089 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
1090 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
1091 writer.write_all(&$htlc_output.payment_hash.0[..])?;
1092 $htlc_output.transaction_output_index.write(writer)?;
1096 writer.write_all(&byte_utils::be64_to_array(self.counterparty_claimable_outpoints.len() as u64))?;
1097 for (ref txid, ref htlc_infos) in self.counterparty_claimable_outpoints.iter() {
1098 writer.write_all(&txid[..])?;
1099 writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
1100 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
1101 serialize_htlc_in_commitment!(htlc_output);
1102 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
1106 writer.write_all(&byte_utils::be64_to_array(self.counterparty_commitment_txn_on_chain.len() as u64))?;
1107 for (ref txid, &(commitment_number, ref txouts)) in self.counterparty_commitment_txn_on_chain.iter() {
1108 writer.write_all(&txid[..])?;
1109 writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
1110 (txouts.len() as u64).write(writer)?;
1111 for script in txouts.iter() {
1112 script.write(writer)?;
1116 writer.write_all(&byte_utils::be64_to_array(self.counterparty_hash_commitment_number.len() as u64))?;
1117 for (ref payment_hash, commitment_number) in self.counterparty_hash_commitment_number.iter() {
1118 writer.write_all(&payment_hash.0[..])?;
1119 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
1122 macro_rules! serialize_holder_tx {
1123 ($holder_tx: expr) => {
1124 $holder_tx.txid.write(writer)?;
1125 writer.write_all(&$holder_tx.revocation_key.serialize())?;
1126 writer.write_all(&$holder_tx.a_htlc_key.serialize())?;
1127 writer.write_all(&$holder_tx.b_htlc_key.serialize())?;
1128 writer.write_all(&$holder_tx.delayed_payment_key.serialize())?;
1129 writer.write_all(&$holder_tx.per_commitment_point.serialize())?;
1131 writer.write_all(&byte_utils::be32_to_array($holder_tx.feerate_per_kw))?;
1132 writer.write_all(&byte_utils::be64_to_array($holder_tx.htlc_outputs.len() as u64))?;
1133 for &(ref htlc_output, ref sig, ref htlc_source) in $holder_tx.htlc_outputs.iter() {
1134 serialize_htlc_in_commitment!(htlc_output);
1135 if let &Some(ref their_sig) = sig {
1137 writer.write_all(&their_sig.serialize_compact())?;
1141 htlc_source.write(writer)?;
1146 if let Some(ref prev_holder_tx) = self.prev_holder_signed_commitment_tx {
1147 writer.write_all(&[1; 1])?;
1148 serialize_holder_tx!(prev_holder_tx);
1150 writer.write_all(&[0; 1])?;
1153 serialize_holder_tx!(self.current_holder_commitment_tx);
1155 writer.write_all(&byte_utils::be48_to_array(self.current_counterparty_commitment_number))?;
1156 writer.write_all(&byte_utils::be48_to_array(self.current_holder_commitment_number))?;
1158 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
1159 for payment_preimage in self.payment_preimages.values() {
1160 writer.write_all(&payment_preimage.0[..])?;
1163 writer.write_all(&byte_utils::be64_to_array(self.pending_monitor_events.len() as u64))?;
1164 for event in self.pending_monitor_events.iter() {
1166 MonitorEvent::HTLCEvent(upd) => {
1170 MonitorEvent::CommitmentTxBroadcasted(_) => 1u8.write(writer)?
1174 writer.write_all(&byte_utils::be64_to_array(self.pending_events.len() as u64))?;
1175 for event in self.pending_events.iter() {
1176 event.write(writer)?;
1179 self.last_block_hash.write(writer)?;
1181 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_waiting_threshold_conf.len() as u64))?;
1182 for (ref target, ref events) in self.onchain_events_waiting_threshold_conf.iter() {
1183 writer.write_all(&byte_utils::be32_to_array(**target))?;
1184 writer.write_all(&byte_utils::be64_to_array(events.len() as u64))?;
1185 for ev in events.iter() {
1187 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1189 htlc_update.0.write(writer)?;
1190 htlc_update.1.write(writer)?;
1192 OnchainEvent::MaturingOutput { ref descriptor } => {
1194 descriptor.write(writer)?;
1200 (self.outputs_to_watch.len() as u64).write(writer)?;
1201 for (txid, output_scripts) in self.outputs_to_watch.iter() {
1202 txid.write(writer)?;
1203 (output_scripts.len() as u64).write(writer)?;
1204 for script in output_scripts.iter() {
1205 script.write(writer)?;
1208 self.onchain_tx_handler.write(writer)?;
1210 self.lockdown_from_offchain.write(writer)?;
1211 self.holder_tx_signed.write(writer)?;
1217 impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
1218 pub(super) fn new(keys: ChanSigner, shutdown_pubkey: &PublicKey,
1219 on_counterparty_tx_csv: u16, destination_script: &Script, funding_info: (OutPoint, Script),
1220 counterparty_htlc_base_key: &PublicKey, counterparty_delayed_payment_base_key: &PublicKey,
1221 on_holder_tx_csv: u16, funding_redeemscript: Script, channel_value_satoshis: u64,
1222 commitment_transaction_number_obscure_factor: u64,
1223 initial_holder_commitment_tx: HolderCommitmentTransaction) -> ChannelMonitor<ChanSigner> {
1225 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
1226 let our_channel_close_key_hash = WPubkeyHash::hash(&shutdown_pubkey.serialize());
1227 let shutdown_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
1228 let payment_key_hash = WPubkeyHash::hash(&keys.pubkeys().payment_point.serialize());
1229 let counterparty_payment_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_key_hash[..]).into_script();
1231 let counterparty_tx_cache = CounterpartyCommitmentTransaction { counterparty_delayed_payment_base_key: *counterparty_delayed_payment_base_key, counterparty_htlc_base_key: *counterparty_htlc_base_key, on_counterparty_tx_csv, per_htlc: HashMap::new() };
1233 let mut onchain_tx_handler = OnchainTxHandler::new(destination_script.clone(), keys.clone(), on_holder_tx_csv);
1235 let holder_tx_sequence = initial_holder_commitment_tx.unsigned_tx.input[0].sequence as u64;
1236 let holder_tx_locktime = initial_holder_commitment_tx.unsigned_tx.lock_time as u64;
1237 let holder_commitment_tx = HolderSignedTx {
1238 txid: initial_holder_commitment_tx.txid(),
1239 revocation_key: initial_holder_commitment_tx.keys.revocation_key,
1240 a_htlc_key: initial_holder_commitment_tx.keys.broadcaster_htlc_key,
1241 b_htlc_key: initial_holder_commitment_tx.keys.countersignatory_htlc_key,
1242 delayed_payment_key: initial_holder_commitment_tx.keys.broadcaster_delayed_payment_key,
1243 per_commitment_point: initial_holder_commitment_tx.keys.per_commitment_point,
1244 feerate_per_kw: initial_holder_commitment_tx.feerate_per_kw,
1245 htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
1247 onchain_tx_handler.provide_latest_holder_tx(initial_holder_commitment_tx);
1250 latest_update_id: 0,
1251 commitment_transaction_number_obscure_factor,
1253 destination_script: destination_script.clone(),
1254 broadcasted_holder_revokable_script: None,
1255 counterparty_payment_script,
1260 current_counterparty_commitment_txid: None,
1261 prev_counterparty_commitment_txid: None,
1263 counterparty_tx_cache,
1264 funding_redeemscript,
1265 channel_value_satoshis: channel_value_satoshis,
1266 their_cur_revocation_points: None,
1270 commitment_secrets: CounterpartyCommitmentSecrets::new(),
1271 counterparty_claimable_outpoints: HashMap::new(),
1272 counterparty_commitment_txn_on_chain: HashMap::new(),
1273 counterparty_hash_commitment_number: HashMap::new(),
1275 prev_holder_signed_commitment_tx: None,
1276 current_holder_commitment_tx: holder_commitment_tx,
1277 current_counterparty_commitment_number: 1 << 48,
1278 current_holder_commitment_number: 0xffff_ffff_ffff - ((((holder_tx_sequence & 0xffffff) << 3*8) | (holder_tx_locktime as u64 & 0xffffff)) ^ commitment_transaction_number_obscure_factor),
1280 payment_preimages: HashMap::new(),
1281 pending_monitor_events: Vec::new(),
1282 pending_events: Vec::new(),
1284 onchain_events_waiting_threshold_conf: HashMap::new(),
1285 outputs_to_watch: HashMap::new(),
1289 lockdown_from_offchain: false,
1290 holder_tx_signed: false,
1292 last_block_hash: Default::default(),
1293 secp_ctx: Secp256k1::new(),
1297 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
1298 /// needed by holder commitment transactions HTCLs nor by counterparty ones. Unless we haven't already seen
1299 /// counterparty commitment transaction's secret, they are de facto pruned (we can use revocation key).
1300 pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
1301 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
1302 return Err(MonitorUpdateError("Previous secret did not match new one"));
1305 // Prune HTLCs from the previous counterparty commitment tx so we don't generate failure/fulfill
1306 // events for now-revoked/fulfilled HTLCs.
1307 if let Some(txid) = self.prev_counterparty_commitment_txid.take() {
1308 for &mut (_, ref mut source) in self.counterparty_claimable_outpoints.get_mut(&txid).unwrap() {
1313 if !self.payment_preimages.is_empty() {
1314 let cur_holder_signed_commitment_tx = &self.current_holder_commitment_tx;
1315 let prev_holder_signed_commitment_tx = self.prev_holder_signed_commitment_tx.as_ref();
1316 let min_idx = self.get_min_seen_secret();
1317 let counterparty_hash_commitment_number = &mut self.counterparty_hash_commitment_number;
1319 self.payment_preimages.retain(|&k, _| {
1320 for &(ref htlc, _, _) in cur_holder_signed_commitment_tx.htlc_outputs.iter() {
1321 if k == htlc.payment_hash {
1325 if let Some(prev_holder_commitment_tx) = prev_holder_signed_commitment_tx {
1326 for &(ref htlc, _, _) in prev_holder_commitment_tx.htlc_outputs.iter() {
1327 if k == htlc.payment_hash {
1332 let contains = if let Some(cn) = counterparty_hash_commitment_number.get(&k) {
1339 counterparty_hash_commitment_number.remove(&k);
1348 /// Informs this monitor of the latest counterparty (ie non-broadcastable) commitment transaction.
1349 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
1350 /// possibly future revocation/preimage information) to claim outputs where possible.
1351 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
1352 pub(super) fn provide_latest_counterparty_commitment_tx_info<L: Deref>(&mut self, unsigned_commitment_tx: &Transaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>, commitment_number: u64, their_revocation_point: PublicKey, logger: &L) where L::Target: Logger {
1353 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
1354 // so that a remote monitor doesn't learn anything unless there is a malicious close.
1355 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
1357 for &(ref htlc, _) in &htlc_outputs {
1358 self.counterparty_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
1361 let new_txid = unsigned_commitment_tx.txid();
1362 log_trace!(logger, "Tracking new counterparty commitment transaction with txid {} at commitment number {} with {} HTLC outputs", new_txid, commitment_number, htlc_outputs.len());
1363 log_trace!(logger, "New potential counterparty commitment transaction: {}", encode::serialize_hex(unsigned_commitment_tx));
1364 self.prev_counterparty_commitment_txid = self.current_counterparty_commitment_txid.take();
1365 self.current_counterparty_commitment_txid = Some(new_txid);
1366 self.counterparty_claimable_outpoints.insert(new_txid, htlc_outputs.clone());
1367 self.current_counterparty_commitment_number = commitment_number;
1368 //TODO: Merge this into the other per-counterparty-transaction output storage stuff
1369 match self.their_cur_revocation_points {
1370 Some(old_points) => {
1371 if old_points.0 == commitment_number + 1 {
1372 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
1373 } else if old_points.0 == commitment_number + 2 {
1374 if let Some(old_second_point) = old_points.2 {
1375 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
1377 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1380 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1384 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1387 let mut htlcs = Vec::with_capacity(htlc_outputs.len());
1388 for htlc in htlc_outputs {
1389 if htlc.0.transaction_output_index.is_some() {
1393 self.counterparty_tx_cache.per_htlc.insert(new_txid, htlcs);
1396 /// Informs this monitor of the latest holder (ie broadcastable) commitment transaction. The
1397 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
1398 /// is important that any clones of this channel monitor (including remote clones) by kept
1399 /// up-to-date as our holder commitment transaction is updated.
1400 /// Panics if set_on_holder_tx_csv has never been called.
1401 pub(super) fn provide_latest_holder_commitment_tx_info(&mut self, commitment_tx: HolderCommitmentTransaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), MonitorUpdateError> {
1402 let txid = commitment_tx.txid();
1403 let sequence = commitment_tx.unsigned_tx.input[0].sequence as u64;
1404 let locktime = commitment_tx.unsigned_tx.lock_time as u64;
1405 let mut new_holder_commitment_tx = HolderSignedTx {
1407 revocation_key: commitment_tx.keys.revocation_key,
1408 a_htlc_key: commitment_tx.keys.broadcaster_htlc_key,
1409 b_htlc_key: commitment_tx.keys.countersignatory_htlc_key,
1410 delayed_payment_key: commitment_tx.keys.broadcaster_delayed_payment_key,
1411 per_commitment_point: commitment_tx.keys.per_commitment_point,
1412 feerate_per_kw: commitment_tx.feerate_per_kw,
1413 htlc_outputs: htlc_outputs,
1415 self.onchain_tx_handler.provide_latest_holder_tx(commitment_tx);
1416 self.current_holder_commitment_number = 0xffff_ffff_ffff - ((((sequence & 0xffffff) << 3*8) | (locktime as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
1417 mem::swap(&mut new_holder_commitment_tx, &mut self.current_holder_commitment_tx);
1418 self.prev_holder_signed_commitment_tx = Some(new_holder_commitment_tx);
1419 if self.holder_tx_signed {
1420 return Err(MonitorUpdateError("Latest holder commitment signed has already been signed, update is rejected"));
1425 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
1426 /// commitment_tx_infos which contain the payment hash have been revoked.
1427 pub(super) fn provide_payment_preimage(&mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage) {
1428 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
1431 pub(super) fn broadcast_latest_holder_commitment_txn<B: Deref, L: Deref>(&mut self, broadcaster: &B, logger: &L)
1432 where B::Target: BroadcasterInterface,
1435 for tx in self.get_latest_holder_commitment_txn(logger).iter() {
1436 broadcaster.broadcast_transaction(tx);
1438 self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0));
1441 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
1444 /// panics if the given update is not the next update by update_id.
1445 pub fn update_monitor<B: Deref, L: Deref>(&mut self, mut updates: ChannelMonitorUpdate, broadcaster: &B, logger: &L) -> Result<(), MonitorUpdateError>
1446 where B::Target: BroadcasterInterface,
1449 if self.latest_update_id + 1 != updates.update_id {
1450 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
1452 for update in updates.updates.drain(..) {
1454 ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { commitment_tx, htlc_outputs } => {
1455 if self.lockdown_from_offchain { panic!(); }
1456 self.provide_latest_holder_commitment_tx_info(commitment_tx, htlc_outputs)?
1458 ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
1459 self.provide_latest_counterparty_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point, logger),
1460 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
1461 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
1462 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
1463 self.provide_secret(idx, secret)?,
1464 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
1465 self.lockdown_from_offchain = true;
1466 if should_broadcast {
1467 self.broadcast_latest_holder_commitment_txn(broadcaster, logger);
1469 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");
1474 self.latest_update_id = updates.update_id;
1478 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
1480 pub fn get_latest_update_id(&self) -> u64 {
1481 self.latest_update_id
1484 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
1485 pub fn get_funding_txo(&self) -> &(OutPoint, Script) {
1489 /// Gets a list of txids, with their output scripts (in the order they appear in the
1490 /// transaction), which we must learn about spends of via block_connected().
1492 /// (C-not exported) because we have no HashMap bindings
1493 pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<Script>> {
1494 &self.outputs_to_watch
1497 /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
1498 /// Generally useful when deserializing as during normal operation the return values of
1499 /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
1500 /// that the get_funding_txo outpoint and transaction must also be monitored for!).
1502 /// (C-not exported) as there is no practical way to track lifetimes of returned values.
1503 pub fn get_monitored_outpoints(&self) -> Vec<(Txid, u32, &Script)> {
1504 let mut res = Vec::with_capacity(self.counterparty_commitment_txn_on_chain.len() * 2);
1505 for (ref txid, &(_, ref outputs)) in self.counterparty_commitment_txn_on_chain.iter() {
1506 for (idx, output) in outputs.iter().enumerate() {
1507 res.push(((*txid).clone(), idx as u32, output));
1513 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1514 /// ChannelManager via ManyChannelMonitor::get_and_clear_pending_monitor_events().
1515 pub fn get_and_clear_pending_monitor_events(&mut self) -> Vec<MonitorEvent> {
1516 let mut ret = Vec::new();
1517 mem::swap(&mut ret, &mut self.pending_monitor_events);
1521 /// Gets the list of pending events which were generated by previous actions, clearing the list
1524 /// This is called by ManyChannelMonitor::get_and_clear_pending_events() and is equivalent to
1525 /// EventsProvider::get_and_clear_pending_events() except that it requires &mut self as we do
1526 /// no internal locking in ChannelMonitors.
1527 pub fn get_and_clear_pending_events(&mut self) -> Vec<Event> {
1528 let mut ret = Vec::new();
1529 mem::swap(&mut ret, &mut self.pending_events);
1533 /// Can only fail if idx is < get_min_seen_secret
1534 pub(super) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
1535 self.commitment_secrets.get_secret(idx)
1538 pub(super) fn get_min_seen_secret(&self) -> u64 {
1539 self.commitment_secrets.get_min_seen_secret()
1542 pub(super) fn get_cur_counterparty_commitment_number(&self) -> u64 {
1543 self.current_counterparty_commitment_number
1546 pub(super) fn get_cur_holder_commitment_number(&self) -> u64 {
1547 self.current_holder_commitment_number
1550 /// Attempts to claim a counterparty commitment transaction's outputs using the revocation key and
1551 /// data in counterparty_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
1552 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
1553 /// HTLC-Success/HTLC-Timeout transactions.
1554 /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
1555 /// revoked counterparty commitment tx
1556 fn check_spend_counterparty_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) where L::Target: Logger {
1557 // Most secp and related errors trying to create keys means we have no hope of constructing
1558 // a spend transaction...so we return no transactions to broadcast
1559 let mut claimable_outpoints = Vec::new();
1560 let mut watch_outputs = Vec::new();
1562 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1563 let per_commitment_option = self.counterparty_claimable_outpoints.get(&commitment_txid);
1565 macro_rules! ignore_error {
1566 ( $thing : expr ) => {
1569 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs))
1574 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);
1575 if commitment_number >= self.get_min_seen_secret() {
1576 let secret = self.get_secret(commitment_number).unwrap();
1577 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1578 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1579 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.keys.pubkeys().revocation_basepoint));
1580 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));
1582 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.counterparty_tx_cache.on_counterparty_tx_csv, &delayed_key);
1583 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1585 // First, process non-htlc outputs (to_holder & to_counterparty)
1586 for (idx, outp) in tx.output.iter().enumerate() {
1587 if outp.script_pubkey == revokeable_p2wsh {
1588 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};
1589 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});
1593 // Then, try to find revoked htlc outputs
1594 if let Some(ref per_commitment_data) = per_commitment_option {
1595 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1596 if let Some(transaction_output_index) = htlc.transaction_output_index {
1597 if transaction_output_index as usize >= tx.output.len() ||
1598 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1599 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1601 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};
1602 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable: true, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1607 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
1608 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
1609 // We're definitely a counterparty commitment transaction!
1610 log_trace!(logger, "Got broadcast of revoked counterparty commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
1611 watch_outputs.append(&mut tx.output.clone());
1612 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1614 macro_rules! check_htlc_fails {
1615 ($txid: expr, $commitment_tx: expr) => {
1616 if let Some(ref outpoints) = self.counterparty_claimable_outpoints.get($txid) {
1617 for &(ref htlc, ref source_option) in outpoints.iter() {
1618 if let &Some(ref source) = source_option {
1619 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), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1620 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1621 hash_map::Entry::Occupied(mut entry) => {
1622 let e = entry.get_mut();
1623 e.retain(|ref event| {
1625 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1626 return htlc_update.0 != **source
1631 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1633 hash_map::Entry::Vacant(entry) => {
1634 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1642 if let Some(ref txid) = self.current_counterparty_commitment_txid {
1643 check_htlc_fails!(txid, "current");
1645 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
1646 check_htlc_fails!(txid, "counterparty");
1648 // No need to check holder commitment txn, symmetric HTLCSource must be present as per-htlc data on counterparty commitment tx
1650 } else if let Some(per_commitment_data) = per_commitment_option {
1651 // While this isn't useful yet, there is a potential race where if a counterparty
1652 // revokes a state at the same time as the commitment transaction for that state is
1653 // confirmed, and the watchtower receives the block before the user, the user could
1654 // upload a new ChannelMonitor with the revocation secret but the watchtower has
1655 // already processed the block, resulting in the counterparty_commitment_txn_on_chain entry
1656 // not being generated by the above conditional. Thus, to be safe, we go ahead and
1658 watch_outputs.append(&mut tx.output.clone());
1659 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1661 log_trace!(logger, "Got broadcast of non-revoked counterparty commitment transaction {}", commitment_txid);
1663 macro_rules! check_htlc_fails {
1664 ($txid: expr, $commitment_tx: expr, $id: tt) => {
1665 if let Some(ref latest_outpoints) = self.counterparty_claimable_outpoints.get($txid) {
1666 $id: for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1667 if let &Some(ref source) = source_option {
1668 // Check if the HTLC is present in the commitment transaction that was
1669 // broadcast, but not if it was below the dust limit, which we should
1670 // fail backwards immediately as there is no way for us to learn the
1671 // payment_preimage.
1672 // Note that if the dust limit were allowed to change between
1673 // commitment transactions we'd want to be check whether *any*
1674 // broadcastable commitment transaction has the HTLC in it, but it
1675 // cannot currently change after channel initialization, so we don't
1677 for &(ref broadcast_htlc, ref broadcast_source) in per_commitment_data.iter() {
1678 if broadcast_htlc.transaction_output_index.is_some() && Some(source) == broadcast_source.as_ref() {
1682 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);
1683 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1684 hash_map::Entry::Occupied(mut entry) => {
1685 let e = entry.get_mut();
1686 e.retain(|ref event| {
1688 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1689 return htlc_update.0 != **source
1694 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1696 hash_map::Entry::Vacant(entry) => {
1697 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1705 if let Some(ref txid) = self.current_counterparty_commitment_txid {
1706 check_htlc_fails!(txid, "current", 'current_loop);
1708 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
1709 check_htlc_fails!(txid, "previous", 'prev_loop);
1712 if let Some(revocation_points) = self.their_cur_revocation_points {
1713 let revocation_point_option =
1714 if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1715 else if let Some(point) = revocation_points.2.as_ref() {
1716 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1718 if let Some(revocation_point) = revocation_point_option {
1719 self.counterparty_payment_script = {
1720 // Note that the Network here is ignored as we immediately drop the address for the
1721 // script_pubkey version
1722 let payment_hash160 = WPubkeyHash::hash(&self.keys.pubkeys().payment_point.serialize());
1723 Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_hash160[..]).into_script()
1726 // Then, try to find htlc outputs
1727 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1728 if let Some(transaction_output_index) = htlc.transaction_output_index {
1729 if transaction_output_index as usize >= tx.output.len() ||
1730 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1731 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1733 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
1734 let aggregable = if !htlc.offered { false } else { true };
1735 if preimage.is_some() || !htlc.offered {
1736 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() };
1737 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1744 (claimable_outpoints, (commitment_txid, watch_outputs))
1747 /// Attempts to claim a counterparty HTLC-Success/HTLC-Timeout's outputs using the revocation key
1748 fn check_spend_counterparty_htlc<L: Deref>(&mut self, tx: &Transaction, commitment_number: u64, height: u32, logger: &L) -> (Vec<ClaimRequest>, Option<(Txid, Vec<TxOut>)>) where L::Target: Logger {
1749 let htlc_txid = tx.txid();
1750 if tx.input.len() != 1 || tx.output.len() != 1 || tx.input[0].witness.len() != 5 {
1751 return (Vec::new(), None)
1754 macro_rules! ignore_error {
1755 ( $thing : expr ) => {
1758 Err(_) => return (Vec::new(), None)
1763 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
1764 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1765 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1767 log_trace!(logger, "Counterparty HTLC broadcast {}:{}", htlc_txid, 0);
1768 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 };
1769 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 });
1770 (claimable_outpoints, Some((htlc_txid, tx.output.clone())))
1773 fn broadcast_by_holder_state(&self, commitment_tx: &Transaction, holder_tx: &HolderSignedTx) -> (Vec<ClaimRequest>, Vec<TxOut>, Option<(Script, PublicKey, PublicKey)>) {
1774 let mut claim_requests = Vec::with_capacity(holder_tx.htlc_outputs.len());
1775 let mut watch_outputs = Vec::with_capacity(holder_tx.htlc_outputs.len());
1777 let redeemscript = chan_utils::get_revokeable_redeemscript(&holder_tx.revocation_key, self.on_holder_tx_csv, &holder_tx.delayed_payment_key);
1778 let broadcasted_holder_revokable_script = Some((redeemscript.to_v0_p2wsh(), holder_tx.per_commitment_point.clone(), holder_tx.revocation_key.clone()));
1780 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
1781 if let Some(transaction_output_index) = htlc.transaction_output_index {
1782 claim_requests.push(ClaimRequest { absolute_timelock: ::std::u32::MAX, aggregable: false, outpoint: BitcoinOutPoint { txid: holder_tx.txid, vout: transaction_output_index as u32 },
1783 witness_data: InputMaterial::HolderHTLC {
1784 preimage: if !htlc.offered {
1785 if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1786 Some(preimage.clone())
1788 // We can't build an HTLC-Success transaction without the preimage
1792 amount: htlc.amount_msat,
1794 watch_outputs.push(commitment_tx.output[transaction_output_index as usize].clone());
1798 (claim_requests, watch_outputs, broadcasted_holder_revokable_script)
1801 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1802 /// revoked using data in holder_claimable_outpoints.
1803 /// Should not be used if check_spend_revoked_transaction succeeds.
1804 fn check_spend_holder_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) where L::Target: Logger {
1805 let commitment_txid = tx.txid();
1806 let mut claim_requests = Vec::new();
1807 let mut watch_outputs = Vec::new();
1809 macro_rules! wait_threshold_conf {
1810 ($height: expr, $source: expr, $commitment_tx: expr, $payment_hash: expr) => {
1811 log_trace!(logger, "Failing HTLC with payment_hash {} from {} holder commitment tx due to broadcast of transaction, waiting confirmation (at height{})", log_bytes!($payment_hash.0), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1812 match self.onchain_events_waiting_threshold_conf.entry($height + ANTI_REORG_DELAY - 1) {
1813 hash_map::Entry::Occupied(mut entry) => {
1814 let e = entry.get_mut();
1815 e.retain(|ref event| {
1817 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1818 return htlc_update.0 != $source
1823 e.push(OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)});
1825 hash_map::Entry::Vacant(entry) => {
1826 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)}]);
1832 macro_rules! append_onchain_update {
1833 ($updates: expr) => {
1834 claim_requests = $updates.0;
1835 watch_outputs.append(&mut $updates.1);
1836 self.broadcasted_holder_revokable_script = $updates.2;
1840 // HTLCs set may differ between last and previous holder commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
1841 let mut is_holder_tx = false;
1843 if self.current_holder_commitment_tx.txid == commitment_txid {
1844 is_holder_tx = true;
1845 log_trace!(logger, "Got latest holder commitment tx broadcast, searching for available HTLCs to claim");
1846 let mut res = self.broadcast_by_holder_state(tx, &self.current_holder_commitment_tx);
1847 append_onchain_update!(res);
1848 } else if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
1849 if holder_tx.txid == commitment_txid {
1850 is_holder_tx = true;
1851 log_trace!(logger, "Got previous holder commitment tx broadcast, searching for available HTLCs to claim");
1852 let mut res = self.broadcast_by_holder_state(tx, holder_tx);
1853 append_onchain_update!(res);
1857 macro_rules! fail_dust_htlcs_after_threshold_conf {
1858 ($holder_tx: expr) => {
1859 for &(ref htlc, _, ref source) in &$holder_tx.htlc_outputs {
1860 if htlc.transaction_output_index.is_none() {
1861 if let &Some(ref source) = source {
1862 wait_threshold_conf!(height, source.clone(), "lastest", htlc.payment_hash.clone());
1870 fail_dust_htlcs_after_threshold_conf!(self.current_holder_commitment_tx);
1871 if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
1872 fail_dust_htlcs_after_threshold_conf!(holder_tx);
1876 (claim_requests, (commitment_txid, watch_outputs))
1879 /// Used by ChannelManager deserialization to broadcast the latest holder state if its copy of
1880 /// the Channel was out-of-date. You may use it to get a broadcastable holder toxic tx in case of
1881 /// fallen-behind, i.e when receiving a channel_reestablish with a proof that our counterparty side knows
1882 /// a higher revocation secret than the holder commitment number we are aware of. Broadcasting these
1883 /// transactions are UNSAFE, as they allow counterparty side to punish you. Nevertheless you may want to
1884 /// broadcast them if counterparty don't close channel with his higher commitment transaction after a
1885 /// substantial amount of time (a month or even a year) to get back funds. Best may be to contact
1886 /// out-of-band the other node operator to coordinate with him if option is available to you.
1887 /// In any-case, choice is up to the user.
1888 pub fn get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1889 log_trace!(logger, "Getting signed latest holder commitment transaction!");
1890 self.holder_tx_signed = true;
1891 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript) {
1892 let txid = commitment_tx.txid();
1893 let mut res = vec![commitment_tx];
1894 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
1895 if let Some(vout) = htlc.0.transaction_output_index {
1896 let preimage = if !htlc.0.offered {
1897 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1898 // We can't build an HTLC-Success transaction without the preimage
1902 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
1903 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1908 // 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.
1909 // The data will be re-generated and tracked in check_spend_holder_transaction if we get a confirmation.
1915 /// Unsafe test-only version of get_latest_holder_commitment_txn used by our test framework
1916 /// to bypass HolderCommitmentTransaction state update lockdown after signature and generate
1917 /// revoked commitment transaction.
1918 #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]
1919 pub fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1920 log_trace!(logger, "Getting signed copy of latest holder commitment transaction!");
1921 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_copy_holder_tx(&self.funding_redeemscript) {
1922 let txid = commitment_tx.txid();
1923 let mut res = vec![commitment_tx];
1924 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
1925 if let Some(vout) = htlc.0.transaction_output_index {
1926 let preimage = if !htlc.0.offered {
1927 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1928 // We can't build an HTLC-Success transaction without the preimage
1932 if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
1933 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1943 /// Called by SimpleManyChannelMonitor::block_connected, which implements
1944 /// ChainListener::block_connected.
1945 /// Eventually this should be pub and, roughly, implement ChainListener, however this requires
1946 /// &mut self, as well as returns new spendable outputs and outpoints to watch for spending of
1948 fn block_connected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, txn_matched: &[(usize, &Transaction)], height: u32, broadcaster: B, fee_estimator: F, logger: L)-> Vec<(Txid, Vec<TxOut>)>
1949 where B::Target: BroadcasterInterface,
1950 F::Target: FeeEstimator,
1953 for &(_, tx) in txn_matched {
1954 let mut output_val = 0;
1955 for out in tx.output.iter() {
1956 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1957 output_val += out.value;
1958 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1962 let block_hash = header.block_hash();
1963 log_trace!(logger, "Block {} at height {} connected with {} txn matched", block_hash, height, txn_matched.len());
1965 let mut watch_outputs = Vec::new();
1966 let mut claimable_outpoints = Vec::new();
1967 for &(_, tx) in txn_matched {
1968 if tx.input.len() == 1 {
1969 // Assuming our keys were not leaked (in which case we're screwed no matter what),
1970 // commitment transactions and HTLC transactions will all only ever have one input,
1971 // which is an easy way to filter out any potential non-matching txn for lazy
1973 let prevout = &tx.input[0].previous_output;
1974 if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
1975 if (tx.input[0].sequence >> 8*3) as u8 == 0x80 && (tx.lock_time >> 8*3) as u8 == 0x20 {
1976 let (mut new_outpoints, new_outputs) = self.check_spend_counterparty_transaction(&tx, height, &logger);
1977 if !new_outputs.1.is_empty() {
1978 watch_outputs.push(new_outputs);
1980 if new_outpoints.is_empty() {
1981 let (mut new_outpoints, new_outputs) = self.check_spend_holder_transaction(&tx, height, &logger);
1982 if !new_outputs.1.is_empty() {
1983 watch_outputs.push(new_outputs);
1985 claimable_outpoints.append(&mut new_outpoints);
1987 claimable_outpoints.append(&mut new_outpoints);
1990 if let Some(&(commitment_number, _)) = self.counterparty_commitment_txn_on_chain.get(&prevout.txid) {
1991 let (mut new_outpoints, new_outputs_option) = self.check_spend_counterparty_htlc(&tx, commitment_number, height, &logger);
1992 claimable_outpoints.append(&mut new_outpoints);
1993 if let Some(new_outputs) = new_outputs_option {
1994 watch_outputs.push(new_outputs);
1999 // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
2000 // can also be resolved in a few other ways which can have more than one output. Thus,
2001 // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
2002 self.is_resolving_htlc_output(&tx, height, &logger);
2004 self.is_paying_spendable_output(&tx, height, &logger);
2006 let should_broadcast = self.would_broadcast_at_height(height, &logger);
2007 if should_broadcast {
2008 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() }});
2010 if should_broadcast {
2011 self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0));
2012 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript) {
2013 self.holder_tx_signed = true;
2014 let (mut new_outpoints, new_outputs, _) = self.broadcast_by_holder_state(&commitment_tx, &self.current_holder_commitment_tx);
2015 if !new_outputs.is_empty() {
2016 watch_outputs.push((self.current_holder_commitment_tx.txid.clone(), new_outputs));
2018 claimable_outpoints.append(&mut new_outpoints);
2021 if let Some(events) = self.onchain_events_waiting_threshold_conf.remove(&height) {
2024 OnchainEvent::HTLCUpdate { htlc_update } => {
2025 log_trace!(logger, "HTLC {} failure update has got enough confirmations to be passed upstream", log_bytes!((htlc_update.1).0));
2026 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2027 payment_hash: htlc_update.1,
2028 payment_preimage: None,
2029 source: htlc_update.0,
2032 OnchainEvent::MaturingOutput { descriptor } => {
2033 log_trace!(logger, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
2034 self.pending_events.push(Event::SpendableOutputs {
2035 outputs: vec![descriptor]
2042 self.onchain_tx_handler.block_connected(txn_matched, claimable_outpoints, height, &*broadcaster, &*fee_estimator, &*logger);
2044 self.last_block_hash = block_hash;
2045 for &(ref txid, ref output_scripts) in watch_outputs.iter() {
2046 self.outputs_to_watch.insert(txid.clone(), output_scripts.iter().map(|o| o.script_pubkey.clone()).collect());
2052 fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, height: u32, broadcaster: B, fee_estimator: F, logger: L)
2053 where B::Target: BroadcasterInterface,
2054 F::Target: FeeEstimator,
2057 let block_hash = header.block_hash();
2058 log_trace!(logger, "Block {} at height {} disconnected", block_hash, height);
2060 if let Some(_) = self.onchain_events_waiting_threshold_conf.remove(&(height + ANTI_REORG_DELAY - 1)) {
2062 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
2063 //- maturing spendable output has transaction paying us has been disconnected
2066 self.onchain_tx_handler.block_disconnected(height, broadcaster, fee_estimator, logger);
2068 self.last_block_hash = block_hash;
2071 fn would_broadcast_at_height<L: Deref>(&self, height: u32, logger: &L) -> bool where L::Target: Logger {
2072 // We need to consider all HTLCs which are:
2073 // * in any unrevoked counterparty commitment transaction, as they could broadcast said
2074 // transactions and we'd end up in a race, or
2075 // * are in our latest holder commitment transaction, as this is the thing we will
2076 // broadcast if we go on-chain.
2077 // Note that we consider HTLCs which were below dust threshold here - while they don't
2078 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
2079 // to the source, and if we don't fail the channel we will have to ensure that the next
2080 // updates that peer sends us are update_fails, failing the channel if not. It's probably
2081 // easier to just fail the channel as this case should be rare enough anyway.
2082 macro_rules! scan_commitment {
2083 ($htlcs: expr, $holder_tx: expr) => {
2084 for ref htlc in $htlcs {
2085 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
2086 // chain with enough room to claim the HTLC without our counterparty being able to
2087 // time out the HTLC first.
2088 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
2089 // concern is being able to claim the corresponding inbound HTLC (on another
2090 // channel) before it expires. In fact, we don't even really care if our
2091 // counterparty here claims such an outbound HTLC after it expired as long as we
2092 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
2093 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
2094 // we give ourselves a few blocks of headroom after expiration before going
2095 // on-chain for an expired HTLC.
2096 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
2097 // from us until we've reached the point where we go on-chain with the
2098 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
2099 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
2100 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
2101 // inbound_cltv == height + CLTV_CLAIM_BUFFER
2102 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
2103 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
2104 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
2105 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
2106 // The final, above, condition is checked for statically in channelmanager
2107 // with CHECK_CLTV_EXPIRY_SANITY_2.
2108 let htlc_outbound = $holder_tx == htlc.offered;
2109 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
2110 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
2111 log_info!(logger, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
2118 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
2120 if let Some(ref txid) = self.current_counterparty_commitment_txid {
2121 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
2122 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2125 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
2126 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
2127 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2134 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a holder
2135 /// or counterparty commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
2136 fn is_resolving_htlc_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2137 'outer_loop: for input in &tx.input {
2138 let mut payment_data = None;
2139 let revocation_sig_claim = (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && input.witness[1].len() == 33)
2140 || (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && input.witness[1].len() == 33);
2141 let accepted_preimage_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::AcceptedHTLC);
2142 let offered_preimage_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC);
2144 macro_rules! log_claim {
2145 ($tx_info: expr, $holder_tx: expr, $htlc: expr, $source_avail: expr) => {
2146 // We found the output in question, but aren't failing it backwards
2147 // as we have no corresponding source and no valid counterparty commitment txid
2148 // to try a weak source binding with same-hash, same-value still-valid offered HTLC.
2149 // This implies either it is an inbound HTLC or an outbound HTLC on a revoked transaction.
2150 let outbound_htlc = $holder_tx == $htlc.offered;
2151 if ($holder_tx && revocation_sig_claim) ||
2152 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
2153 log_error!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
2154 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2155 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2156 if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back" });
2158 log_info!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
2159 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2160 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2161 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
2166 macro_rules! check_htlc_valid_counterparty {
2167 ($counterparty_txid: expr, $htlc_output: expr) => {
2168 if let Some(txid) = $counterparty_txid {
2169 for &(ref pending_htlc, ref pending_source) in self.counterparty_claimable_outpoints.get(&txid).unwrap() {
2170 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
2171 if let &Some(ref source) = pending_source {
2172 log_claim!("revoked counterparty commitment tx", false, pending_htlc, true);
2173 payment_data = Some(((**source).clone(), $htlc_output.payment_hash));
2182 macro_rules! scan_commitment {
2183 ($htlcs: expr, $tx_info: expr, $holder_tx: expr) => {
2184 for (ref htlc_output, source_option) in $htlcs {
2185 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
2186 if let Some(ref source) = source_option {
2187 log_claim!($tx_info, $holder_tx, htlc_output, true);
2188 // We have a resolution of an HTLC either from one of our latest
2189 // holder commitment transactions or an unrevoked counterparty commitment
2190 // transaction. This implies we either learned a preimage, the HTLC
2191 // has timed out, or we screwed up. In any case, we should now
2192 // resolve the source HTLC with the original sender.
2193 payment_data = Some(((*source).clone(), htlc_output.payment_hash));
2194 } else if !$holder_tx {
2195 check_htlc_valid_counterparty!(self.current_counterparty_commitment_txid, htlc_output);
2196 if payment_data.is_none() {
2197 check_htlc_valid_counterparty!(self.prev_counterparty_commitment_txid, htlc_output);
2200 if payment_data.is_none() {
2201 log_claim!($tx_info, $holder_tx, htlc_output, false);
2202 continue 'outer_loop;
2209 if input.previous_output.txid == self.current_holder_commitment_tx.txid {
2210 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2211 "our latest holder commitment tx", true);
2213 if let Some(ref prev_holder_signed_commitment_tx) = self.prev_holder_signed_commitment_tx {
2214 if input.previous_output.txid == prev_holder_signed_commitment_tx.txid {
2215 scan_commitment!(prev_holder_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2216 "our previous holder commitment tx", true);
2219 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(&input.previous_output.txid) {
2220 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
2221 "counterparty commitment tx", false);
2224 // Check that scan_commitment, above, decided there is some source worth relaying an
2225 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
2226 if let Some((source, payment_hash)) = payment_data {
2227 let mut payment_preimage = PaymentPreimage([0; 32]);
2228 if accepted_preimage_claim {
2229 if !self.pending_monitor_events.iter().any(
2230 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update { upd.source == source } else { false }) {
2231 payment_preimage.0.copy_from_slice(&input.witness[3]);
2232 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2234 payment_preimage: Some(payment_preimage),
2238 } else if offered_preimage_claim {
2239 if !self.pending_monitor_events.iter().any(
2240 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update {
2241 upd.source == source
2243 payment_preimage.0.copy_from_slice(&input.witness[1]);
2244 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2246 payment_preimage: Some(payment_preimage),
2251 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);
2252 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2253 hash_map::Entry::Occupied(mut entry) => {
2254 let e = entry.get_mut();
2255 e.retain(|ref event| {
2257 OnchainEvent::HTLCUpdate { ref htlc_update } => {
2258 return htlc_update.0 != source
2263 e.push(OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)});
2265 hash_map::Entry::Vacant(entry) => {
2266 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)}]);
2274 /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
2275 fn is_paying_spendable_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2276 let mut spendable_output = None;
2277 for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
2278 if i > ::std::u16::MAX as usize {
2279 // While it is possible that an output exists on chain which is greater than the
2280 // 2^16th output in a given transaction, this is only possible if the output is not
2281 // in a lightning transaction and was instead placed there by some third party who
2282 // wishes to give us money for no reason.
2283 // Namely, any lightning transactions which we pre-sign will never have anywhere
2284 // near 2^16 outputs both because such transactions must have ~2^16 outputs who's
2285 // scripts are not longer than one byte in length and because they are inherently
2286 // non-standard due to their size.
2287 // Thus, it is completely safe to ignore such outputs, and while it may result in
2288 // us ignoring non-lightning fund to us, that is only possible if someone fills
2289 // nearly a full block with garbage just to hit this case.
2292 if outp.script_pubkey == self.destination_script {
2293 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2294 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2295 output: outp.clone(),
2298 } else if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
2299 if broadcasted_holder_revokable_script.0 == outp.script_pubkey {
2300 spendable_output = Some(SpendableOutputDescriptor::DynamicOutputP2WSH {
2301 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2302 per_commitment_point: broadcasted_holder_revokable_script.1,
2303 to_self_delay: self.on_holder_tx_csv,
2304 output: outp.clone(),
2305 key_derivation_params: self.keys.key_derivation_params(),
2306 revocation_pubkey: broadcasted_holder_revokable_script.2.clone(),
2310 } else if self.counterparty_payment_script == outp.script_pubkey {
2311 spendable_output = Some(SpendableOutputDescriptor::StaticOutputCounterpartyPayment {
2312 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2313 output: outp.clone(),
2314 key_derivation_params: self.keys.key_derivation_params(),
2317 } else if outp.script_pubkey == self.shutdown_script {
2318 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2319 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2320 output: outp.clone(),
2324 if let Some(spendable_output) = spendable_output {
2325 log_trace!(logger, "Maturing {} until {}", log_spendable!(spendable_output), height + ANTI_REORG_DELAY - 1);
2326 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2327 hash_map::Entry::Occupied(mut entry) => {
2328 let e = entry.get_mut();
2329 e.push(OnchainEvent::MaturingOutput { descriptor: spendable_output });
2331 hash_map::Entry::Vacant(entry) => {
2332 entry.insert(vec![OnchainEvent::MaturingOutput { descriptor: spendable_output }]);
2339 const MAX_ALLOC_SIZE: usize = 64*1024;
2341 impl<ChanSigner: ChannelKeys + Readable> Readable for (BlockHash, ChannelMonitor<ChanSigner>) {
2342 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
2343 macro_rules! unwrap_obj {
2347 Err(_) => return Err(DecodeError::InvalidValue),
2352 let _ver: u8 = Readable::read(reader)?;
2353 let min_ver: u8 = Readable::read(reader)?;
2354 if min_ver > SERIALIZATION_VERSION {
2355 return Err(DecodeError::UnknownVersion);
2358 let latest_update_id: u64 = Readable::read(reader)?;
2359 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
2361 let destination_script = Readable::read(reader)?;
2362 let broadcasted_holder_revokable_script = match <u8 as Readable>::read(reader)? {
2364 let revokable_address = Readable::read(reader)?;
2365 let per_commitment_point = Readable::read(reader)?;
2366 let revokable_script = Readable::read(reader)?;
2367 Some((revokable_address, per_commitment_point, revokable_script))
2370 _ => return Err(DecodeError::InvalidValue),
2372 let counterparty_payment_script = Readable::read(reader)?;
2373 let shutdown_script = Readable::read(reader)?;
2375 let keys = Readable::read(reader)?;
2376 // Technically this can fail and serialize fail a round-trip, but only for serialization of
2377 // barely-init'd ChannelMonitors that we can't do anything with.
2378 let outpoint = OutPoint {
2379 txid: Readable::read(reader)?,
2380 index: Readable::read(reader)?,
2382 let funding_info = (outpoint, Readable::read(reader)?);
2383 let current_counterparty_commitment_txid = Readable::read(reader)?;
2384 let prev_counterparty_commitment_txid = Readable::read(reader)?;
2386 let counterparty_tx_cache = Readable::read(reader)?;
2387 let funding_redeemscript = Readable::read(reader)?;
2388 let channel_value_satoshis = Readable::read(reader)?;
2390 let their_cur_revocation_points = {
2391 let first_idx = <U48 as Readable>::read(reader)?.0;
2395 let first_point = Readable::read(reader)?;
2396 let second_point_slice: [u8; 33] = Readable::read(reader)?;
2397 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
2398 Some((first_idx, first_point, None))
2400 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
2405 let on_holder_tx_csv: u16 = Readable::read(reader)?;
2407 let commitment_secrets = Readable::read(reader)?;
2409 macro_rules! read_htlc_in_commitment {
2412 let offered: bool = Readable::read(reader)?;
2413 let amount_msat: u64 = Readable::read(reader)?;
2414 let cltv_expiry: u32 = Readable::read(reader)?;
2415 let payment_hash: PaymentHash = Readable::read(reader)?;
2416 let transaction_output_index: Option<u32> = Readable::read(reader)?;
2418 HTLCOutputInCommitment {
2419 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
2425 let counterparty_claimable_outpoints_len: u64 = Readable::read(reader)?;
2426 let mut counterparty_claimable_outpoints = HashMap::with_capacity(cmp::min(counterparty_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
2427 for _ in 0..counterparty_claimable_outpoints_len {
2428 let txid: Txid = Readable::read(reader)?;
2429 let htlcs_count: u64 = Readable::read(reader)?;
2430 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
2431 for _ in 0..htlcs_count {
2432 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
2434 if let Some(_) = counterparty_claimable_outpoints.insert(txid, htlcs) {
2435 return Err(DecodeError::InvalidValue);
2439 let counterparty_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
2440 let mut counterparty_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(counterparty_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
2441 for _ in 0..counterparty_commitment_txn_on_chain_len {
2442 let txid: Txid = Readable::read(reader)?;
2443 let commitment_number = <U48 as Readable>::read(reader)?.0;
2444 let outputs_count = <u64 as Readable>::read(reader)?;
2445 let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 8));
2446 for _ in 0..outputs_count {
2447 outputs.push(Readable::read(reader)?);
2449 if let Some(_) = counterparty_commitment_txn_on_chain.insert(txid, (commitment_number, outputs)) {
2450 return Err(DecodeError::InvalidValue);
2454 let counterparty_hash_commitment_number_len: u64 = Readable::read(reader)?;
2455 let mut counterparty_hash_commitment_number = HashMap::with_capacity(cmp::min(counterparty_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
2456 for _ in 0..counterparty_hash_commitment_number_len {
2457 let payment_hash: PaymentHash = Readable::read(reader)?;
2458 let commitment_number = <U48 as Readable>::read(reader)?.0;
2459 if let Some(_) = counterparty_hash_commitment_number.insert(payment_hash, commitment_number) {
2460 return Err(DecodeError::InvalidValue);
2464 macro_rules! read_holder_tx {
2467 let txid = Readable::read(reader)?;
2468 let revocation_key = Readable::read(reader)?;
2469 let a_htlc_key = Readable::read(reader)?;
2470 let b_htlc_key = Readable::read(reader)?;
2471 let delayed_payment_key = Readable::read(reader)?;
2472 let per_commitment_point = Readable::read(reader)?;
2473 let feerate_per_kw: u32 = Readable::read(reader)?;
2475 let htlcs_len: u64 = Readable::read(reader)?;
2476 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_len as usize, MAX_ALLOC_SIZE / 128));
2477 for _ in 0..htlcs_len {
2478 let htlc = read_htlc_in_commitment!();
2479 let sigs = match <u8 as Readable>::read(reader)? {
2481 1 => Some(Readable::read(reader)?),
2482 _ => return Err(DecodeError::InvalidValue),
2484 htlcs.push((htlc, sigs, Readable::read(reader)?));
2489 revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, per_commitment_point, feerate_per_kw,
2496 let prev_holder_signed_commitment_tx = match <u8 as Readable>::read(reader)? {
2499 Some(read_holder_tx!())
2501 _ => return Err(DecodeError::InvalidValue),
2503 let current_holder_commitment_tx = read_holder_tx!();
2505 let current_counterparty_commitment_number = <U48 as Readable>::read(reader)?.0;
2506 let current_holder_commitment_number = <U48 as Readable>::read(reader)?.0;
2508 let payment_preimages_len: u64 = Readable::read(reader)?;
2509 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
2510 for _ in 0..payment_preimages_len {
2511 let preimage: PaymentPreimage = Readable::read(reader)?;
2512 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2513 if let Some(_) = payment_preimages.insert(hash, preimage) {
2514 return Err(DecodeError::InvalidValue);
2518 let pending_monitor_events_len: u64 = Readable::read(reader)?;
2519 let mut pending_monitor_events = Vec::with_capacity(cmp::min(pending_monitor_events_len as usize, MAX_ALLOC_SIZE / (32 + 8*3)));
2520 for _ in 0..pending_monitor_events_len {
2521 let ev = match <u8 as Readable>::read(reader)? {
2522 0 => MonitorEvent::HTLCEvent(Readable::read(reader)?),
2523 1 => MonitorEvent::CommitmentTxBroadcasted(funding_info.0),
2524 _ => return Err(DecodeError::InvalidValue)
2526 pending_monitor_events.push(ev);
2529 let pending_events_len: u64 = Readable::read(reader)?;
2530 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Event>()));
2531 for _ in 0..pending_events_len {
2532 if let Some(event) = MaybeReadable::read(reader)? {
2533 pending_events.push(event);
2537 let last_block_hash: BlockHash = Readable::read(reader)?;
2539 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
2540 let mut onchain_events_waiting_threshold_conf = HashMap::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
2541 for _ in 0..waiting_threshold_conf_len {
2542 let height_target = Readable::read(reader)?;
2543 let events_len: u64 = Readable::read(reader)?;
2544 let mut events = Vec::with_capacity(cmp::min(events_len as usize, MAX_ALLOC_SIZE / 128));
2545 for _ in 0..events_len {
2546 let ev = match <u8 as Readable>::read(reader)? {
2548 let htlc_source = Readable::read(reader)?;
2549 let hash = Readable::read(reader)?;
2550 OnchainEvent::HTLCUpdate {
2551 htlc_update: (htlc_source, hash)
2555 let descriptor = Readable::read(reader)?;
2556 OnchainEvent::MaturingOutput {
2560 _ => return Err(DecodeError::InvalidValue),
2564 onchain_events_waiting_threshold_conf.insert(height_target, events);
2567 let outputs_to_watch_len: u64 = Readable::read(reader)?;
2568 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::<Vec<Script>>())));
2569 for _ in 0..outputs_to_watch_len {
2570 let txid = Readable::read(reader)?;
2571 let outputs_len: u64 = Readable::read(reader)?;
2572 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Script>()));
2573 for _ in 0..outputs_len {
2574 outputs.push(Readable::read(reader)?);
2576 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
2577 return Err(DecodeError::InvalidValue);
2580 let onchain_tx_handler = Readable::read(reader)?;
2582 let lockdown_from_offchain = Readable::read(reader)?;
2583 let holder_tx_signed = Readable::read(reader)?;
2585 Ok((last_block_hash.clone(), ChannelMonitor {
2587 commitment_transaction_number_obscure_factor,
2590 broadcasted_holder_revokable_script,
2591 counterparty_payment_script,
2596 current_counterparty_commitment_txid,
2597 prev_counterparty_commitment_txid,
2599 counterparty_tx_cache,
2600 funding_redeemscript,
2601 channel_value_satoshis,
2602 their_cur_revocation_points,
2607 counterparty_claimable_outpoints,
2608 counterparty_commitment_txn_on_chain,
2609 counterparty_hash_commitment_number,
2611 prev_holder_signed_commitment_tx,
2612 current_holder_commitment_tx,
2613 current_counterparty_commitment_number,
2614 current_holder_commitment_number,
2617 pending_monitor_events,
2620 onchain_events_waiting_threshold_conf,
2625 lockdown_from_offchain,
2629 secp_ctx: Secp256k1::new(),
2636 use bitcoin::blockdata::script::{Script, Builder};
2637 use bitcoin::blockdata::opcodes;
2638 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, SigHashType};
2639 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
2640 use bitcoin::util::bip143;
2641 use bitcoin::hashes::Hash;
2642 use bitcoin::hashes::sha256::Hash as Sha256;
2643 use bitcoin::hashes::hex::FromHex;
2644 use bitcoin::hash_types::Txid;
2646 use chain::transaction::OutPoint;
2647 use ln::channelmanager::{PaymentPreimage, PaymentHash};
2648 use ln::channelmonitor::ChannelMonitor;
2649 use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
2651 use ln::chan_utils::{HTLCOutputInCommitment, HolderCommitmentTransaction};
2652 use util::test_utils::TestLogger;
2653 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
2654 use bitcoin::secp256k1::Secp256k1;
2656 use chain::keysinterface::InMemoryChannelKeys;
2659 fn test_prune_preimages() {
2660 let secp_ctx = Secp256k1::new();
2661 let logger = Arc::new(TestLogger::new());
2663 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
2664 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2666 let mut preimages = Vec::new();
2669 let preimage = PaymentPreimage([i; 32]);
2670 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2671 preimages.push((preimage, hash));
2675 macro_rules! preimages_slice_to_htlc_outputs {
2676 ($preimages_slice: expr) => {
2678 let mut res = Vec::new();
2679 for (idx, preimage) in $preimages_slice.iter().enumerate() {
2680 res.push((HTLCOutputInCommitment {
2684 payment_hash: preimage.1.clone(),
2685 transaction_output_index: Some(idx as u32),
2692 macro_rules! preimages_to_holder_htlcs {
2693 ($preimages_slice: expr) => {
2695 let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2696 let res: Vec<_> = inp.drain(..).map(|e| { (e.0, None, e.1) }).collect();
2702 macro_rules! test_preimages_exist {
2703 ($preimages_slice: expr, $monitor: expr) => {
2704 for preimage in $preimages_slice {
2705 assert!($monitor.payment_preimages.contains_key(&preimage.1));
2710 let keys = InMemoryChannelKeys::new(
2712 SecretKey::from_slice(&[41; 32]).unwrap(),
2713 SecretKey::from_slice(&[41; 32]).unwrap(),
2714 SecretKey::from_slice(&[41; 32]).unwrap(),
2715 SecretKey::from_slice(&[41; 32]).unwrap(),
2716 SecretKey::from_slice(&[41; 32]).unwrap(),
2722 // Prune with one old state and a holder commitment tx holding a few overlaps with the
2724 let mut monitor = ChannelMonitor::new(keys,
2725 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()), 0, &Script::new(),
2726 (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
2727 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
2728 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
2729 10, Script::new(), 46, 0, HolderCommitmentTransaction::dummy());
2731 monitor.provide_latest_holder_commitment_tx_info(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..10])).unwrap();
2732 monitor.provide_latest_counterparty_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
2733 monitor.provide_latest_counterparty_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
2734 monitor.provide_latest_counterparty_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
2735 monitor.provide_latest_counterparty_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
2736 for &(ref preimage, ref hash) in preimages.iter() {
2737 monitor.provide_payment_preimage(hash, preimage);
2740 // Now provide a secret, pruning preimages 10-15
2741 let mut secret = [0; 32];
2742 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2743 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2744 assert_eq!(monitor.payment_preimages.len(), 15);
2745 test_preimages_exist!(&preimages[0..10], monitor);
2746 test_preimages_exist!(&preimages[15..20], monitor);
2748 // Now provide a further secret, pruning preimages 15-17
2749 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2750 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2751 assert_eq!(monitor.payment_preimages.len(), 13);
2752 test_preimages_exist!(&preimages[0..10], monitor);
2753 test_preimages_exist!(&preimages[17..20], monitor);
2755 // Now update holder commitment tx info, pruning only element 18 as we still care about the
2756 // previous commitment tx's preimages too
2757 monitor.provide_latest_holder_commitment_tx_info(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..5])).unwrap();
2758 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2759 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2760 assert_eq!(monitor.payment_preimages.len(), 12);
2761 test_preimages_exist!(&preimages[0..10], monitor);
2762 test_preimages_exist!(&preimages[18..20], monitor);
2764 // But if we do it again, we'll prune 5-10
2765 monitor.provide_latest_holder_commitment_tx_info(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..3])).unwrap();
2766 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2767 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2768 assert_eq!(monitor.payment_preimages.len(), 5);
2769 test_preimages_exist!(&preimages[0..5], monitor);
2773 fn test_claim_txn_weight_computation() {
2774 // We test Claim txn weight, knowing that we want expected weigth and
2775 // not actual case to avoid sigs and time-lock delays hell variances.
2777 let secp_ctx = Secp256k1::new();
2778 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
2779 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
2780 let mut sum_actual_sigs = 0;
2782 macro_rules! sign_input {
2783 ($sighash_parts: expr, $idx: expr, $amount: expr, $input_type: expr, $sum_actual_sigs: expr) => {
2784 let htlc = HTLCOutputInCommitment {
2785 offered: if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::OfferedHTLC { true } else { false },
2787 cltv_expiry: 2 << 16,
2788 payment_hash: PaymentHash([1; 32]),
2789 transaction_output_index: Some($idx as u32),
2791 let redeem_script = if *$input_type == InputDescriptors::RevokedOutput { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &pubkey, &pubkey, &pubkey) };
2792 let sighash = hash_to_message!(&$sighash_parts.signature_hash($idx, &redeem_script, $amount, SigHashType::All)[..]);
2793 let sig = secp_ctx.sign(&sighash, &privkey);
2794 $sighash_parts.access_witness($idx).push(sig.serialize_der().to_vec());
2795 $sighash_parts.access_witness($idx)[0].push(SigHashType::All as u8);
2796 sum_actual_sigs += $sighash_parts.access_witness($idx)[0].len();
2797 if *$input_type == InputDescriptors::RevokedOutput {
2798 $sighash_parts.access_witness($idx).push(vec!(1));
2799 } else if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::RevokedReceivedHTLC {
2800 $sighash_parts.access_witness($idx).push(pubkey.clone().serialize().to_vec());
2801 } else if *$input_type == InputDescriptors::ReceivedHTLC {
2802 $sighash_parts.access_witness($idx).push(vec![0]);
2804 $sighash_parts.access_witness($idx).push(PaymentPreimage([1; 32]).0.to_vec());
2806 $sighash_parts.access_witness($idx).push(redeem_script.into_bytes());
2807 println!("witness[0] {}", $sighash_parts.access_witness($idx)[0].len());
2808 println!("witness[1] {}", $sighash_parts.access_witness($idx)[1].len());
2809 println!("witness[2] {}", $sighash_parts.access_witness($idx)[2].len());
2813 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
2814 let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
2816 // Justice tx with 1 to_holder, 2 revoked offered HTLCs, 1 revoked received HTLCs
2817 let mut claim_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2819 claim_tx.input.push(TxIn {
2820 previous_output: BitcoinOutPoint {
2824 script_sig: Script::new(),
2825 sequence: 0xfffffffd,
2826 witness: Vec::new(),
2829 claim_tx.output.push(TxOut {
2830 script_pubkey: script_pubkey.clone(),
2833 let base_weight = claim_tx.get_weight();
2834 let inputs_des = vec![InputDescriptors::RevokedOutput, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedReceivedHTLC];
2836 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
2837 for (idx, inp) in inputs_des.iter().enumerate() {
2838 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
2841 assert_eq!(base_weight + OnchainTxHandler::<InMemoryChannelKeys>::get_witnesses_weight(&inputs_des[..]), claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_des.len() - sum_actual_sigs));
2843 // Claim tx with 1 offered HTLCs, 3 received HTLCs
2844 claim_tx.input.clear();
2845 sum_actual_sigs = 0;
2847 claim_tx.input.push(TxIn {
2848 previous_output: BitcoinOutPoint {
2852 script_sig: Script::new(),
2853 sequence: 0xfffffffd,
2854 witness: Vec::new(),
2857 let base_weight = claim_tx.get_weight();
2858 let inputs_des = vec![InputDescriptors::OfferedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC];
2860 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
2861 for (idx, inp) in inputs_des.iter().enumerate() {
2862 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
2865 assert_eq!(base_weight + OnchainTxHandler::<InMemoryChannelKeys>::get_witnesses_weight(&inputs_des[..]), claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_des.len() - sum_actual_sigs));
2867 // Justice tx with 1 revoked HTLC-Success tx output
2868 claim_tx.input.clear();
2869 sum_actual_sigs = 0;
2870 claim_tx.input.push(TxIn {
2871 previous_output: BitcoinOutPoint {
2875 script_sig: Script::new(),
2876 sequence: 0xfffffffd,
2877 witness: Vec::new(),
2879 let base_weight = claim_tx.get_weight();
2880 let inputs_des = vec![InputDescriptors::RevokedOutput];
2882 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
2883 for (idx, inp) in inputs_des.iter().enumerate() {
2884 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
2887 assert_eq!(base_weight + OnchainTxHandler::<InMemoryChannelKeys>::get_witnesses_weight(&inputs_des[..]), claim_tx.get_weight() + /* max_length_isg */ (73 * inputs_des.len() - sum_actual_sigs));
2890 // Further testing is done in the ChannelManager integration tests.