1 // This file is Copyright its original authors, visible in version control
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
7 // You may not use this file except in accordance with one or both of these
10 //! The logic to monitor for on-chain transactions and create the relevant claim responses lives
13 //! ChannelMonitor objects are generated by ChannelManager in response to relevant
14 //! messages/actions, and MUST be persisted to disk (and, preferably, remotely) before progress can
15 //! be made in responding to certain messages, see [`chain::Watch`] for more.
17 //! Note that ChannelMonitors are an important part of the lightning trust model and a copy of the
18 //! latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date
19 //! ChannelMonitors should do so). Thus, if you're building rust-lightning into an HSM or other
20 //! security-domain-separated system design, you should consider having multiple paths for
21 //! ChannelMonitors to get out of the HSM and onto monitoring devices.
23 //! [`chain::Watch`]: ../../chain/trait.Watch.html
25 use bitcoin::blockdata::block::BlockHeader;
26 use bitcoin::blockdata::transaction::{TxOut,Transaction};
27 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
28 use bitcoin::blockdata::script::{Script, Builder};
29 use bitcoin::blockdata::opcodes;
30 use bitcoin::consensus::encode;
32 use bitcoin::hashes::Hash;
33 use bitcoin::hashes::sha256::Hash as Sha256;
34 use bitcoin::hash_types::{Txid, BlockHash, WPubkeyHash};
36 use bitcoin::secp256k1::{Secp256k1,Signature};
37 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
38 use bitcoin::secp256k1;
40 use ln::msgs::DecodeError;
42 use ln::chan_utils::{CounterpartyCommitmentSecrets, HTLCOutputInCommitment, HolderCommitmentTransaction, HTLCType};
43 use ln::channelmanager::{HTLCSource, PaymentPreimage, PaymentHash};
44 use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
46 use chain::chaininterface::{ChainListener, ChainWatchedUtil, BroadcasterInterface, FeeEstimator};
47 use chain::transaction::OutPoint;
48 use chain::keysinterface::{SpendableOutputDescriptor, ChannelKeys};
49 use util::logger::Logger;
50 use util::ser::{Readable, MaybeReadable, Writer, Writeable, U48};
51 use util::{byte_utils, events};
52 use util::events::Event;
54 use std::collections::{HashMap, HashSet, hash_map};
56 use std::{hash,cmp, mem};
60 /// An update generated by the underlying Channel itself which contains some new information the
61 /// ChannelMonitor should be made aware of.
62 #[cfg_attr(test, derive(PartialEq))]
65 pub struct ChannelMonitorUpdate {
66 pub(super) updates: Vec<ChannelMonitorUpdateStep>,
67 /// The sequence number of this update. Updates *must* be replayed in-order according to this
68 /// sequence number (and updates may panic if they are not). The update_id values are strictly
69 /// increasing and increase by one for each new update.
71 /// This sequence number is also used to track up to which points updates which returned
72 /// ChannelMonitorUpdateErr::TemporaryFailure have been applied to all copies of a given
73 /// ChannelMonitor when ChannelManager::channel_monitor_updated is called.
77 impl Writeable for ChannelMonitorUpdate {
78 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
79 self.update_id.write(w)?;
80 (self.updates.len() as u64).write(w)?;
81 for update_step in self.updates.iter() {
82 update_step.write(w)?;
87 impl Readable for ChannelMonitorUpdate {
88 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
89 let update_id: u64 = Readable::read(r)?;
90 let len: u64 = Readable::read(r)?;
91 let mut updates = Vec::with_capacity(cmp::min(len as usize, MAX_ALLOC_SIZE / ::std::mem::size_of::<ChannelMonitorUpdateStep>()));
93 updates.push(Readable::read(r)?);
95 Ok(Self { update_id, updates })
99 /// An error enum representing a failure to persist a channel monitor update.
101 pub enum ChannelMonitorUpdateErr {
102 /// Used to indicate a temporary failure (eg connection to a watchtower or remote backup of
103 /// our state failed, but is expected to succeed at some point in the future).
105 /// Such a failure will "freeze" a channel, preventing us from revoking old states or
106 /// submitting new commitment transactions to the counterparty. Once the update(s) which failed
107 /// have been successfully applied, ChannelManager::channel_monitor_updated can be used to
108 /// restore the channel to an operational state.
110 /// Note that a given ChannelManager will *never* re-generate a given ChannelMonitorUpdate. If
111 /// you return a TemporaryFailure you must ensure that it is written to disk safely before
112 /// writing out the latest ChannelManager state.
114 /// Even when a channel has been "frozen" updates to the ChannelMonitor can continue to occur
115 /// (eg if an inbound HTLC which we forwarded was claimed upstream resulting in us attempting
116 /// to claim it on this channel) and those updates must be applied wherever they can be. At
117 /// least one such updated ChannelMonitor must be persisted otherwise PermanentFailure should
118 /// be returned to get things on-chain ASAP using only the in-memory copy. Obviously updates to
119 /// the channel which would invalidate previous ChannelMonitors are not made when a channel has
122 /// Note that even if updates made after TemporaryFailure succeed you must still call
123 /// channel_monitor_updated to ensure you have the latest monitor and re-enable normal channel
126 /// Note that the update being processed here will not be replayed for you when you call
127 /// ChannelManager::channel_monitor_updated, so you must store the update itself along
128 /// with the persisted ChannelMonitor on your own local disk prior to returning a
129 /// TemporaryFailure. You may, of course, employ a journaling approach, storing only the
130 /// ChannelMonitorUpdate on disk without updating the monitor itself, replaying the journal at
133 /// For deployments where a copy of ChannelMonitors and other local state are backed up in a
134 /// remote location (with local copies persisted immediately), it is anticipated that all
135 /// updates will return TemporaryFailure until the remote copies could be updated.
137 /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
138 /// different watchtower and cannot update with all watchtowers that were previously informed
139 /// of this channel).
141 /// At reception of this error, ChannelManager will force-close the channel and return at
142 /// least a final ChannelMonitorUpdate::ChannelForceClosed which must be delivered to at
143 /// least one ChannelMonitor copy. Revocation secret MUST NOT be released and offchain channel
144 /// update must be rejected.
146 /// This failure may also signal a failure to update the local persisted copy of one of
147 /// the channel monitor instance.
149 /// Note that even when you fail a holder commitment transaction update, you must store the
150 /// update to ensure you can claim from it in case of a duplicate copy of this ChannelMonitor
151 /// broadcasts it (e.g distributed channel-monitor deployment)
153 /// In case of distributed watchtowers deployment, the new version must be written to disk, as
154 /// state may have been stored but rejected due to a block forcing a commitment broadcast. This
155 /// storage is used to claim outputs of rejected state confirmed onchain by another watchtower,
156 /// lagging behind on block processing.
160 /// General Err type for ChannelMonitor actions. Generally, this implies that the data provided is
161 /// inconsistent with the ChannelMonitor being called. eg for ChannelMonitor::update_monitor this
162 /// means you tried to update a monitor for a different channel or the ChannelMonitorUpdate was
164 /// Contains a human-readable error message.
166 pub struct MonitorUpdateError(pub &'static str);
168 /// An event to be processed by the ChannelManager.
170 pub enum MonitorEvent {
171 /// A monitor event containing an HTLCUpdate.
172 HTLCEvent(HTLCUpdate),
174 /// A monitor event that the Channel's commitment transaction was broadcasted.
175 CommitmentTxBroadcasted(OutPoint),
178 /// Simple structure sent back by `chain::Watch` when an HTLC from a forward channel is detected on
179 /// chain. Used to update the corresponding HTLC in the backward channel. Failing to pass the
180 /// preimage claim backward will lead to loss of funds.
182 /// [`chain::Watch`]: ../../chain/trait.Watch.html
183 #[derive(Clone, PartialEq)]
184 pub struct HTLCUpdate {
185 pub(super) payment_hash: PaymentHash,
186 pub(super) payment_preimage: Option<PaymentPreimage>,
187 pub(super) source: HTLCSource
189 impl_writeable!(HTLCUpdate, 0, { payment_hash, payment_preimage, source });
191 /// A simple implementation of a [`chain::Watch`] and ChainListener. Can be used to create a
192 /// watchtower or watch our own channels.
194 /// Note that you must provide your own key by which to refer to channels.
196 /// If you're accepting remote monitors (ie are implementing a watchtower), you must verify that
197 /// users cannot overwrite a given channel by providing a duplicate key. ie you should probably
198 /// index by a PublicKey which is required to sign any updates.
200 /// If you're using this for local monitoring of your own channels, you probably want to use
201 /// `OutPoint` as the key, which will give you a [`chain::Watch`] implementation.
203 /// [`chain::Watch`]: ../../chain/trait.Watch.html
205 /// (C-not exported) due to an unconstrained generic in `Key`
206 pub struct SimpleManyChannelMonitor<Key, ChanSigner: ChannelKeys, T: Deref, F: Deref, L: Deref>
207 where T::Target: BroadcasterInterface,
208 F::Target: FeeEstimator,
212 pub monitors: Mutex<HashMap<Key, ChannelMonitor<ChanSigner>>>,
213 watch_events: Mutex<WatchEventQueue>,
219 struct WatchEventQueue {
220 watched: ChainWatchedUtil,
221 events: Vec<chain::WatchEvent>,
224 impl WatchEventQueue {
227 watched: ChainWatchedUtil::new(),
232 fn watch_tx(&mut self, txid: &Txid, script_pubkey: &Script) {
233 if self.watched.register_tx(txid, script_pubkey) {
234 self.events.push(chain::WatchEvent::WatchTransaction {
236 script_pubkey: script_pubkey.clone()
241 fn watch_output(&mut self, outpoint: (&Txid, usize), script_pubkey: &Script) {
242 let (txid, index) = outpoint;
243 if self.watched.register_outpoint((*txid, index as u32), script_pubkey) {
244 self.events.push(chain::WatchEvent::WatchOutput {
249 script_pubkey: script_pubkey.clone(),
254 fn dequeue_events(&mut self) -> Vec<chain::WatchEvent> {
255 let mut pending_events = Vec::with_capacity(self.events.len());
256 pending_events.append(&mut self.events);
260 fn filter_block<'a>(&self, txdata: &[(usize, &'a Transaction)]) -> Vec<(usize, &'a Transaction)> {
261 let mut matched_txids = HashSet::new();
262 txdata.iter().filter(|&&(_, tx)| {
263 // A tx matches the filter if it either matches the filter directly (via does_match_tx)
264 // or if it is a descendant of another matched transaction within the same block.
265 let mut matched = self.watched.does_match_tx(tx);
266 for input in tx.input.iter() {
267 if matched || matched_txids.contains(&input.previous_output.txid) {
273 matched_txids.insert(tx.txid());
276 }).map(|e| *e).collect()
280 impl<Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys, T: Deref + Sync + Send, F: Deref + Sync + Send, L: Deref + Sync + Send>
281 ChainListener for SimpleManyChannelMonitor<Key, ChanSigner, T, F, L>
282 where T::Target: BroadcasterInterface,
283 F::Target: FeeEstimator,
286 fn block_connected(&self, header: &BlockHeader, txdata: &[(usize, &Transaction)], height: u32) {
287 let mut watch_events = self.watch_events.lock().unwrap();
288 let matched_txn = watch_events.filter_block(txdata);
290 let mut monitors = self.monitors.lock().unwrap();
291 for monitor in monitors.values_mut() {
292 let txn_outputs = monitor.block_connected(header, &matched_txn, height, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
294 for (ref txid, ref outputs) in txn_outputs {
295 for (idx, output) in outputs.iter().enumerate() {
296 watch_events.watch_output((txid, idx), &output.script_pubkey);
303 fn block_disconnected(&self, header: &BlockHeader, disconnected_height: u32) {
304 let mut monitors = self.monitors.lock().unwrap();
305 for monitor in monitors.values_mut() {
306 monitor.block_disconnected(header, disconnected_height, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
311 impl<Key : Send + cmp::Eq + hash::Hash + 'static, ChanSigner: ChannelKeys, T: Deref, F: Deref, L: Deref> SimpleManyChannelMonitor<Key, ChanSigner, T, F, L>
312 where T::Target: BroadcasterInterface,
313 F::Target: FeeEstimator,
316 /// Creates a new object which can be used to monitor several channels given the chain
317 /// interface with which to register to receive notifications.
318 pub fn new(broadcaster: T, logger: L, feeest: F) -> SimpleManyChannelMonitor<Key, ChanSigner, T, F, L> {
319 let res = SimpleManyChannelMonitor {
320 monitors: Mutex::new(HashMap::new()),
321 watch_events: Mutex::new(WatchEventQueue::new()),
324 fee_estimator: feeest,
330 /// Adds or updates the monitor which monitors the channel referred to by the given key.
331 fn add_monitor_by_key(&self, key: Key, monitor: ChannelMonitor<ChanSigner>) -> Result<(), MonitorUpdateError> {
332 let mut watch_events = self.watch_events.lock().unwrap();
333 let mut monitors = self.monitors.lock().unwrap();
334 let entry = match monitors.entry(key) {
335 hash_map::Entry::Occupied(_) => return Err(MonitorUpdateError("Channel monitor for given key is already present")),
336 hash_map::Entry::Vacant(e) => e,
339 let funding_txo = monitor.get_funding_txo();
340 log_trace!(self.logger, "Got new Channel Monitor for channel {}", log_bytes!(funding_txo.0.to_channel_id()[..]));
341 watch_events.watch_tx(&funding_txo.0.txid, &funding_txo.1);
342 watch_events.watch_output((&funding_txo.0.txid, funding_txo.0.index as usize), &funding_txo.1);
343 for (txid, outputs) in monitor.get_outputs_to_watch().iter() {
344 for (idx, script) in outputs.iter().enumerate() {
345 watch_events.watch_output((txid, idx), script);
349 entry.insert(monitor);
353 /// Updates the monitor which monitors the channel referred to by the given key.
354 fn update_monitor_by_key(&self, key: Key, update: ChannelMonitorUpdate) -> Result<(), MonitorUpdateError> {
355 let mut monitors = self.monitors.lock().unwrap();
356 match monitors.get_mut(&key) {
357 Some(orig_monitor) => {
358 log_trace!(self.logger, "Updating Channel Monitor for channel {}", log_funding_info!(orig_monitor));
359 orig_monitor.update_monitor(update, &self.broadcaster, &self.logger)
361 None => Err(MonitorUpdateError("No such monitor registered"))
366 impl<ChanSigner: ChannelKeys, T: Deref + Sync + Send, F: Deref + Sync + Send, L: Deref + Sync + Send> chain::Watch for SimpleManyChannelMonitor<OutPoint, ChanSigner, T, F, L>
367 where T::Target: BroadcasterInterface,
368 F::Target: FeeEstimator,
371 type Keys = ChanSigner;
373 fn watch_channel(&self, funding_txo: OutPoint, monitor: ChannelMonitor<ChanSigner>) -> Result<(), ChannelMonitorUpdateErr> {
374 match self.add_monitor_by_key(funding_txo, monitor) {
376 Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
380 fn update_channel(&self, funding_txo: OutPoint, update: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr> {
381 match self.update_monitor_by_key(funding_txo, update) {
383 Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
387 fn release_pending_monitor_events(&self) -> Vec<MonitorEvent> {
388 let mut pending_monitor_events = Vec::new();
389 for chan in self.monitors.lock().unwrap().values_mut() {
390 pending_monitor_events.append(&mut chan.get_and_clear_pending_monitor_events());
392 pending_monitor_events
396 impl<Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys, T: Deref, F: Deref, L: Deref> events::EventsProvider for SimpleManyChannelMonitor<Key, ChanSigner, T, F, L>
397 where T::Target: BroadcasterInterface,
398 F::Target: FeeEstimator,
401 fn get_and_clear_pending_events(&self) -> Vec<Event> {
402 let mut pending_events = Vec::new();
403 for chan in self.monitors.lock().unwrap().values_mut() {
404 pending_events.append(&mut chan.get_and_clear_pending_events());
410 impl<Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys, T: Deref, F: Deref, L: Deref> chain::WatchEventProvider for SimpleManyChannelMonitor<Key, ChanSigner, T, F, L>
411 where T::Target: BroadcasterInterface,
412 F::Target: FeeEstimator,
415 fn release_pending_watch_events(&self) -> Vec<chain::WatchEvent> {
416 self.watch_events.lock().unwrap().dequeue_events()
420 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
421 /// instead claiming it in its own individual transaction.
422 pub(crate) const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
423 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
424 /// HTLC-Success transaction.
425 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
426 /// transaction confirmed (and we use it in a few more, equivalent, places).
427 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 6;
428 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
429 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
430 /// copies of ChannelMonitors, including watchtowers). We could enforce the contract by failing
431 /// at CLTV expiration height but giving a grace period to our peer may be profitable for us if he
432 /// can provide an over-late preimage. Nevertheless, grace period has to be accounted in our
433 /// CLTV_EXPIRY_DELTA to be secure. Following this policy we may decrease the rate of channel failures
434 /// due to expiration but increase the cost of funds being locked longuer in case of failure.
435 /// This delay also cover a low-power peer being slow to process blocks and so being behind us on
436 /// accurate block height.
437 /// In case of onchain failure to be pass backward we may see the last block of ANTI_REORG_DELAY
438 /// with at worst this delay, so we are not only using this value as a mercy for them but also
439 /// us as a safeguard to delay with enough time.
440 pub(crate) const LATENCY_GRACE_PERIOD_BLOCKS: u32 = 3;
441 /// Number of blocks we wait on seeing a HTLC output being solved before we fail corresponding inbound
442 /// HTLCs. This prevents us from failing backwards and then getting a reorg resulting in us losing money.
443 /// We use also this delay to be sure we can remove our in-flight claim txn from bump candidates buffer.
444 /// It may cause spurrious generation of bumped claim txn but that's allright given the outpoint is already
445 /// solved by a previous claim tx. What we want to avoid is reorg evicting our claim tx and us not
446 /// keeping bumping another claim tx to solve the outpoint.
447 pub(crate) const ANTI_REORG_DELAY: u32 = 6;
448 /// Number of blocks before confirmation at which we fail back an un-relayed HTLC or at which we
449 /// refuse to accept a new HTLC.
451 /// This is used for a few separate purposes:
452 /// 1) if we've received an MPP HTLC to us and it expires within this many blocks and we are
453 /// waiting on additional parts (or waiting on the preimage for any HTLC from the user), we will
455 /// 2) if we receive an HTLC within this many blocks of its expiry (plus one to avoid a race
456 /// condition with the above), we will fail this HTLC without telling the user we received it,
457 /// 3) if we are waiting on a connection or a channel state update to send an HTLC to a peer, and
458 /// that HTLC expires within this many blocks, we will simply fail the HTLC instead.
460 /// (1) is all about protecting us - we need enough time to update the channel state before we hit
461 /// CLTV_CLAIM_BUFFER, at which point we'd go on chain to claim the HTLC with the preimage.
463 /// (2) is the same, but with an additional buffer to avoid accepting an HTLC which is immediately
464 /// in a race condition between the user connecting a block (which would fail it) and the user
465 /// providing us the preimage (which would claim it).
467 /// (3) is about our counterparty - we don't want to relay an HTLC to a counterparty when they may
468 /// end up force-closing the channel on us to claim it.
469 pub(crate) const HTLC_FAIL_BACK_BUFFER: u32 = CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS;
471 #[derive(Clone, PartialEq)]
472 struct HolderSignedTx {
473 /// txid of the transaction in tx, just used to make comparison faster
475 revocation_key: PublicKey,
476 a_htlc_key: PublicKey,
477 b_htlc_key: PublicKey,
478 delayed_payment_key: PublicKey,
479 per_commitment_point: PublicKey,
481 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
484 /// We use this to track counterparty commitment transactions and htlcs outputs and
485 /// use it to generate any justice or 2nd-stage preimage/timeout transactions.
487 struct CounterpartyCommitmentTransaction {
488 counterparty_delayed_payment_base_key: PublicKey,
489 counterparty_htlc_base_key: PublicKey,
490 on_counterparty_tx_csv: u16,
491 per_htlc: HashMap<Txid, Vec<HTLCOutputInCommitment>>
494 impl Writeable for CounterpartyCommitmentTransaction {
495 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
496 self.counterparty_delayed_payment_base_key.write(w)?;
497 self.counterparty_htlc_base_key.write(w)?;
498 w.write_all(&byte_utils::be16_to_array(self.on_counterparty_tx_csv))?;
499 w.write_all(&byte_utils::be64_to_array(self.per_htlc.len() as u64))?;
500 for (ref txid, ref htlcs) in self.per_htlc.iter() {
501 w.write_all(&txid[..])?;
502 w.write_all(&byte_utils::be64_to_array(htlcs.len() as u64))?;
503 for &ref htlc in htlcs.iter() {
510 impl Readable for CounterpartyCommitmentTransaction {
511 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
512 let counterparty_commitment_transaction = {
513 let counterparty_delayed_payment_base_key = Readable::read(r)?;
514 let counterparty_htlc_base_key = Readable::read(r)?;
515 let on_counterparty_tx_csv: u16 = Readable::read(r)?;
516 let per_htlc_len: u64 = Readable::read(r)?;
517 let mut per_htlc = HashMap::with_capacity(cmp::min(per_htlc_len as usize, MAX_ALLOC_SIZE / 64));
518 for _ in 0..per_htlc_len {
519 let txid: Txid = Readable::read(r)?;
520 let htlcs_count: u64 = Readable::read(r)?;
521 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
522 for _ in 0..htlcs_count {
523 let htlc = Readable::read(r)?;
526 if let Some(_) = per_htlc.insert(txid, htlcs) {
527 return Err(DecodeError::InvalidValue);
530 CounterpartyCommitmentTransaction {
531 counterparty_delayed_payment_base_key,
532 counterparty_htlc_base_key,
533 on_counterparty_tx_csv,
537 Ok(counterparty_commitment_transaction)
541 /// When ChannelMonitor discovers an onchain outpoint being a step of a channel and that it needs
542 /// to generate a tx to push channel state forward, we cache outpoint-solving tx material to build
543 /// a new bumped one in case of lenghty confirmation delay
544 #[derive(Clone, PartialEq)]
545 pub(crate) enum InputMaterial {
547 per_commitment_point: PublicKey,
548 counterparty_delayed_payment_base_key: PublicKey,
549 counterparty_htlc_base_key: PublicKey,
550 per_commitment_key: SecretKey,
551 input_descriptor: InputDescriptors,
553 htlc: Option<HTLCOutputInCommitment>,
554 on_counterparty_tx_csv: u16,
557 per_commitment_point: PublicKey,
558 counterparty_delayed_payment_base_key: PublicKey,
559 counterparty_htlc_base_key: PublicKey,
560 preimage: Option<PaymentPreimage>,
561 htlc: HTLCOutputInCommitment
564 preimage: Option<PaymentPreimage>,
568 funding_redeemscript: Script,
572 impl Writeable for InputMaterial {
573 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
575 &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} => {
576 writer.write_all(&[0; 1])?;
577 per_commitment_point.write(writer)?;
578 counterparty_delayed_payment_base_key.write(writer)?;
579 counterparty_htlc_base_key.write(writer)?;
580 writer.write_all(&per_commitment_key[..])?;
581 input_descriptor.write(writer)?;
582 writer.write_all(&byte_utils::be64_to_array(*amount))?;
584 on_counterparty_tx_csv.write(writer)?;
586 &InputMaterial::CounterpartyHTLC { ref per_commitment_point, ref counterparty_delayed_payment_base_key, ref counterparty_htlc_base_key, ref preimage, ref htlc} => {
587 writer.write_all(&[1; 1])?;
588 per_commitment_point.write(writer)?;
589 counterparty_delayed_payment_base_key.write(writer)?;
590 counterparty_htlc_base_key.write(writer)?;
591 preimage.write(writer)?;
594 &InputMaterial::HolderHTLC { ref preimage, ref amount } => {
595 writer.write_all(&[2; 1])?;
596 preimage.write(writer)?;
597 writer.write_all(&byte_utils::be64_to_array(*amount))?;
599 &InputMaterial::Funding { ref funding_redeemscript } => {
600 writer.write_all(&[3; 1])?;
601 funding_redeemscript.write(writer)?;
608 impl Readable for InputMaterial {
609 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
610 let input_material = match <u8 as Readable>::read(reader)? {
612 let per_commitment_point = Readable::read(reader)?;
613 let counterparty_delayed_payment_base_key = Readable::read(reader)?;
614 let counterparty_htlc_base_key = Readable::read(reader)?;
615 let per_commitment_key = Readable::read(reader)?;
616 let input_descriptor = Readable::read(reader)?;
617 let amount = Readable::read(reader)?;
618 let htlc = Readable::read(reader)?;
619 let on_counterparty_tx_csv = Readable::read(reader)?;
620 InputMaterial::Revoked {
621 per_commitment_point,
622 counterparty_delayed_payment_base_key,
623 counterparty_htlc_base_key,
628 on_counterparty_tx_csv
632 let per_commitment_point = Readable::read(reader)?;
633 let counterparty_delayed_payment_base_key = Readable::read(reader)?;
634 let counterparty_htlc_base_key = Readable::read(reader)?;
635 let preimage = Readable::read(reader)?;
636 let htlc = Readable::read(reader)?;
637 InputMaterial::CounterpartyHTLC {
638 per_commitment_point,
639 counterparty_delayed_payment_base_key,
640 counterparty_htlc_base_key,
646 let preimage = Readable::read(reader)?;
647 let amount = Readable::read(reader)?;
648 InputMaterial::HolderHTLC {
654 InputMaterial::Funding {
655 funding_redeemscript: Readable::read(reader)?,
658 _ => return Err(DecodeError::InvalidValue),
664 /// ClaimRequest is a descriptor structure to communicate between detection
665 /// and reaction module. They are generated by ChannelMonitor while parsing
666 /// onchain txn leaked from a channel and handed over to OnchainTxHandler which
667 /// is responsible for opportunistic aggregation, selecting and enforcing
668 /// bumping logic, building and signing transactions.
669 pub(crate) struct ClaimRequest {
670 // Block height before which claiming is exclusive to one party,
671 // after reaching it, claiming may be contentious.
672 pub(crate) absolute_timelock: u32,
673 // Timeout tx must have nLocktime set which means aggregating multiple
674 // ones must take the higher nLocktime among them to satisfy all of them.
675 // Sadly it has few pitfalls, a) it takes longuer to get fund back b) CLTV_DELTA
676 // of a sooner-HTLC could be swallowed by the highest nLocktime of the HTLC set.
677 // Do simplify we mark them as non-aggregable.
678 pub(crate) aggregable: bool,
679 // Basic bitcoin outpoint (txid, vout)
680 pub(crate) outpoint: BitcoinOutPoint,
681 // Following outpoint type, set of data needed to generate transaction digest
682 // and satisfy witness program.
683 pub(crate) witness_data: InputMaterial
686 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
687 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
688 #[derive(Clone, PartialEq)]
690 /// HTLC output getting solved by a timeout, at maturation we pass upstream payment source information to solve
691 /// inbound HTLC in backward channel. Note, in case of preimage, we pass info to upstream without delay as we can
692 /// only win from it, so it's never an OnchainEvent
694 htlc_update: (HTLCSource, PaymentHash),
697 descriptor: SpendableOutputDescriptor,
701 const SERIALIZATION_VERSION: u8 = 1;
702 const MIN_SERIALIZATION_VERSION: u8 = 1;
704 #[cfg_attr(test, derive(PartialEq))]
706 pub(super) enum ChannelMonitorUpdateStep {
707 LatestHolderCommitmentTXInfo {
708 commitment_tx: HolderCommitmentTransaction,
709 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
711 LatestCounterpartyCommitmentTXInfo {
712 unsigned_commitment_tx: Transaction, // TODO: We should actually only need the txid here
713 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
714 commitment_number: u64,
715 their_revocation_point: PublicKey,
718 payment_preimage: PaymentPreimage,
724 /// Used to indicate that the no future updates will occur, and likely that the latest holder
725 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
727 /// If set to false, we shouldn't broadcast the latest holder commitment transaction as we
728 /// think we've fallen behind!
729 should_broadcast: bool,
733 impl Writeable for ChannelMonitorUpdateStep {
734 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
736 &ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { ref commitment_tx, ref htlc_outputs } => {
738 commitment_tx.write(w)?;
739 (htlc_outputs.len() as u64).write(w)?;
740 for &(ref output, ref signature, ref source) in htlc_outputs.iter() {
746 &ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { ref unsigned_commitment_tx, ref htlc_outputs, ref commitment_number, ref their_revocation_point } => {
748 unsigned_commitment_tx.write(w)?;
749 commitment_number.write(w)?;
750 their_revocation_point.write(w)?;
751 (htlc_outputs.len() as u64).write(w)?;
752 for &(ref output, ref source) in htlc_outputs.iter() {
754 source.as_ref().map(|b| b.as_ref()).write(w)?;
757 &ChannelMonitorUpdateStep::PaymentPreimage { ref payment_preimage } => {
759 payment_preimage.write(w)?;
761 &ChannelMonitorUpdateStep::CommitmentSecret { ref idx, ref secret } => {
766 &ChannelMonitorUpdateStep::ChannelForceClosed { ref should_broadcast } => {
768 should_broadcast.write(w)?;
774 impl Readable for ChannelMonitorUpdateStep {
775 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
776 match Readable::read(r)? {
778 Ok(ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo {
779 commitment_tx: Readable::read(r)?,
781 let len: u64 = Readable::read(r)?;
782 let mut res = Vec::new();
784 res.push((Readable::read(r)?, Readable::read(r)?, Readable::read(r)?));
791 Ok(ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo {
792 unsigned_commitment_tx: Readable::read(r)?,
793 commitment_number: Readable::read(r)?,
794 their_revocation_point: Readable::read(r)?,
796 let len: u64 = Readable::read(r)?;
797 let mut res = Vec::new();
799 res.push((Readable::read(r)?, <Option<HTLCSource> as Readable>::read(r)?.map(|o| Box::new(o))));
806 Ok(ChannelMonitorUpdateStep::PaymentPreimage {
807 payment_preimage: Readable::read(r)?,
811 Ok(ChannelMonitorUpdateStep::CommitmentSecret {
812 idx: Readable::read(r)?,
813 secret: Readable::read(r)?,
817 Ok(ChannelMonitorUpdateStep::ChannelForceClosed {
818 should_broadcast: Readable::read(r)?
821 _ => Err(DecodeError::InvalidValue),
826 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
827 /// on-chain transactions to ensure no loss of funds occurs.
829 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
830 /// information and are actively monitoring the chain.
832 /// Pending Events or updated HTLCs which have not yet been read out by
833 /// get_and_clear_pending_monitor_events or get_and_clear_pending_events are serialized to disk and
834 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
835 /// gotten are fully handled before re-serializing the new state.
836 pub struct ChannelMonitor<ChanSigner: ChannelKeys> {
837 latest_update_id: u64,
838 commitment_transaction_number_obscure_factor: u64,
840 destination_script: Script,
841 broadcasted_holder_revokable_script: Option<(Script, PublicKey, PublicKey)>,
842 counterparty_payment_script: Script,
843 shutdown_script: Script,
846 funding_info: (OutPoint, Script),
847 current_counterparty_commitment_txid: Option<Txid>,
848 prev_counterparty_commitment_txid: Option<Txid>,
850 counterparty_tx_cache: CounterpartyCommitmentTransaction,
851 funding_redeemscript: Script,
852 channel_value_satoshis: u64,
853 // first is the idx of the first of the two revocation points
854 their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
856 on_holder_tx_csv: u16,
858 commitment_secrets: CounterpartyCommitmentSecrets,
859 counterparty_claimable_outpoints: HashMap<Txid, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
860 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
861 /// Nor can we figure out their commitment numbers without the commitment transaction they are
862 /// spending. Thus, in order to claim them via revocation key, we track all the counterparty
863 /// commitment transactions which we find on-chain, mapping them to the commitment number which
864 /// can be used to derive the revocation key and claim the transactions.
865 counterparty_commitment_txn_on_chain: HashMap<Txid, (u64, Vec<Script>)>,
866 /// Cache used to make pruning of payment_preimages faster.
867 /// Maps payment_hash values to commitment numbers for counterparty transactions for non-revoked
868 /// counterparty transactions (ie should remain pretty small).
869 /// Serialized to disk but should generally not be sent to Watchtowers.
870 counterparty_hash_commitment_number: HashMap<PaymentHash, u64>,
872 // We store two holder commitment transactions to avoid any race conditions where we may update
873 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
874 // various monitors for one channel being out of sync, and us broadcasting a holder
875 // transaction for which we have deleted claim information on some watchtowers.
876 prev_holder_signed_commitment_tx: Option<HolderSignedTx>,
877 current_holder_commitment_tx: HolderSignedTx,
879 // Used just for ChannelManager to make sure it has the latest channel data during
881 current_counterparty_commitment_number: u64,
882 // Used just for ChannelManager to make sure it has the latest channel data during
884 current_holder_commitment_number: u64,
886 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
888 pending_monitor_events: Vec<MonitorEvent>,
889 pending_events: Vec<Event>,
891 // Used to track onchain events, i.e transactions parts of channels confirmed on chain, on which
892 // we have to take actions once they reach enough confs. Key is a block height timer, i.e we enforce
893 // actions when we receive a block with given height. Actions depend on OnchainEvent type.
894 onchain_events_waiting_threshold_conf: HashMap<u32, Vec<OnchainEvent>>,
896 // If we get serialized out and re-read, we need to make sure that the chain monitoring
897 // interface knows about the TXOs that we want to be notified of spends of. We could probably
898 // be smart and derive them from the above storage fields, but its much simpler and more
899 // Obviously Correct (tm) if we just keep track of them explicitly.
900 outputs_to_watch: HashMap<Txid, Vec<Script>>,
903 pub onchain_tx_handler: OnchainTxHandler<ChanSigner>,
905 onchain_tx_handler: OnchainTxHandler<ChanSigner>,
907 // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
908 // channel has been force-closed. After this is set, no further holder commitment transaction
909 // updates may occur, and we panic!() if one is provided.
910 lockdown_from_offchain: bool,
912 // Set once we've signed a holder commitment transaction and handed it over to our
913 // OnchainTxHandler. After this is set, no future updates to our holder commitment transactions
914 // may occur, and we fail any such monitor updates.
916 // In case of update rejection due to a locally already signed commitment transaction, we
917 // nevertheless store update content to track in case of concurrent broadcast by another
918 // remote monitor out-of-order with regards to the block view.
919 holder_tx_signed: bool,
921 // We simply modify last_block_hash in Channel's block_connected so that serialization is
922 // consistent but hopefully the users' copy handles block_connected in a consistent way.
923 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
924 // their last_block_hash from its state and not based on updated copies that didn't run through
925 // the full block_connected).
926 last_block_hash: BlockHash,
927 secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
930 #[cfg(any(test, feature = "fuzztarget"))]
931 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
932 /// underlying object
933 impl<ChanSigner: ChannelKeys> PartialEq for ChannelMonitor<ChanSigner> {
934 fn eq(&self, other: &Self) -> bool {
935 if self.latest_update_id != other.latest_update_id ||
936 self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
937 self.destination_script != other.destination_script ||
938 self.broadcasted_holder_revokable_script != other.broadcasted_holder_revokable_script ||
939 self.counterparty_payment_script != other.counterparty_payment_script ||
940 self.keys.pubkeys() != other.keys.pubkeys() ||
941 self.funding_info != other.funding_info ||
942 self.current_counterparty_commitment_txid != other.current_counterparty_commitment_txid ||
943 self.prev_counterparty_commitment_txid != other.prev_counterparty_commitment_txid ||
944 self.counterparty_tx_cache != other.counterparty_tx_cache ||
945 self.funding_redeemscript != other.funding_redeemscript ||
946 self.channel_value_satoshis != other.channel_value_satoshis ||
947 self.their_cur_revocation_points != other.their_cur_revocation_points ||
948 self.on_holder_tx_csv != other.on_holder_tx_csv ||
949 self.commitment_secrets != other.commitment_secrets ||
950 self.counterparty_claimable_outpoints != other.counterparty_claimable_outpoints ||
951 self.counterparty_commitment_txn_on_chain != other.counterparty_commitment_txn_on_chain ||
952 self.counterparty_hash_commitment_number != other.counterparty_hash_commitment_number ||
953 self.prev_holder_signed_commitment_tx != other.prev_holder_signed_commitment_tx ||
954 self.current_counterparty_commitment_number != other.current_counterparty_commitment_number ||
955 self.current_holder_commitment_number != other.current_holder_commitment_number ||
956 self.current_holder_commitment_tx != other.current_holder_commitment_tx ||
957 self.payment_preimages != other.payment_preimages ||
958 self.pending_monitor_events != other.pending_monitor_events ||
959 self.pending_events.len() != other.pending_events.len() || // We trust events to round-trip properly
960 self.onchain_events_waiting_threshold_conf != other.onchain_events_waiting_threshold_conf ||
961 self.outputs_to_watch != other.outputs_to_watch ||
962 self.lockdown_from_offchain != other.lockdown_from_offchain ||
963 self.holder_tx_signed != other.holder_tx_signed
972 impl<ChanSigner: ChannelKeys + Writeable> ChannelMonitor<ChanSigner> {
973 /// Writes this monitor into the given writer, suitable for writing to disk.
975 /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
976 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
977 /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
978 /// returned block hash and the the current chain and then reconnecting blocks to get to the
979 /// best chain) upon deserializing the object!
980 pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
981 //TODO: We still write out all the serialization here manually instead of using the fancy
982 //serialization framework we have, we should migrate things over to it.
983 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
984 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
986 self.latest_update_id.write(writer)?;
988 // Set in initial Channel-object creation, so should always be set by now:
989 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
991 self.destination_script.write(writer)?;
992 if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
993 writer.write_all(&[0; 1])?;
994 broadcasted_holder_revokable_script.0.write(writer)?;
995 broadcasted_holder_revokable_script.1.write(writer)?;
996 broadcasted_holder_revokable_script.2.write(writer)?;
998 writer.write_all(&[1; 1])?;
1001 self.counterparty_payment_script.write(writer)?;
1002 self.shutdown_script.write(writer)?;
1004 self.keys.write(writer)?;
1005 writer.write_all(&self.funding_info.0.txid[..])?;
1006 writer.write_all(&byte_utils::be16_to_array(self.funding_info.0.index))?;
1007 self.funding_info.1.write(writer)?;
1008 self.current_counterparty_commitment_txid.write(writer)?;
1009 self.prev_counterparty_commitment_txid.write(writer)?;
1011 self.counterparty_tx_cache.write(writer)?;
1012 self.funding_redeemscript.write(writer)?;
1013 self.channel_value_satoshis.write(writer)?;
1015 match self.their_cur_revocation_points {
1016 Some((idx, pubkey, second_option)) => {
1017 writer.write_all(&byte_utils::be48_to_array(idx))?;
1018 writer.write_all(&pubkey.serialize())?;
1019 match second_option {
1020 Some(second_pubkey) => {
1021 writer.write_all(&second_pubkey.serialize())?;
1024 writer.write_all(&[0; 33])?;
1029 writer.write_all(&byte_utils::be48_to_array(0))?;
1033 writer.write_all(&byte_utils::be16_to_array(self.on_holder_tx_csv))?;
1035 self.commitment_secrets.write(writer)?;
1037 macro_rules! serialize_htlc_in_commitment {
1038 ($htlc_output: expr) => {
1039 writer.write_all(&[$htlc_output.offered as u8; 1])?;
1040 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
1041 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
1042 writer.write_all(&$htlc_output.payment_hash.0[..])?;
1043 $htlc_output.transaction_output_index.write(writer)?;
1047 writer.write_all(&byte_utils::be64_to_array(self.counterparty_claimable_outpoints.len() as u64))?;
1048 for (ref txid, ref htlc_infos) in self.counterparty_claimable_outpoints.iter() {
1049 writer.write_all(&txid[..])?;
1050 writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
1051 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
1052 serialize_htlc_in_commitment!(htlc_output);
1053 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
1057 writer.write_all(&byte_utils::be64_to_array(self.counterparty_commitment_txn_on_chain.len() as u64))?;
1058 for (ref txid, &(commitment_number, ref txouts)) in self.counterparty_commitment_txn_on_chain.iter() {
1059 writer.write_all(&txid[..])?;
1060 writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
1061 (txouts.len() as u64).write(writer)?;
1062 for script in txouts.iter() {
1063 script.write(writer)?;
1067 writer.write_all(&byte_utils::be64_to_array(self.counterparty_hash_commitment_number.len() as u64))?;
1068 for (ref payment_hash, commitment_number) in self.counterparty_hash_commitment_number.iter() {
1069 writer.write_all(&payment_hash.0[..])?;
1070 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
1073 macro_rules! serialize_holder_tx {
1074 ($holder_tx: expr) => {
1075 $holder_tx.txid.write(writer)?;
1076 writer.write_all(&$holder_tx.revocation_key.serialize())?;
1077 writer.write_all(&$holder_tx.a_htlc_key.serialize())?;
1078 writer.write_all(&$holder_tx.b_htlc_key.serialize())?;
1079 writer.write_all(&$holder_tx.delayed_payment_key.serialize())?;
1080 writer.write_all(&$holder_tx.per_commitment_point.serialize())?;
1082 writer.write_all(&byte_utils::be32_to_array($holder_tx.feerate_per_kw))?;
1083 writer.write_all(&byte_utils::be64_to_array($holder_tx.htlc_outputs.len() as u64))?;
1084 for &(ref htlc_output, ref sig, ref htlc_source) in $holder_tx.htlc_outputs.iter() {
1085 serialize_htlc_in_commitment!(htlc_output);
1086 if let &Some(ref their_sig) = sig {
1088 writer.write_all(&their_sig.serialize_compact())?;
1092 htlc_source.write(writer)?;
1097 if let Some(ref prev_holder_tx) = self.prev_holder_signed_commitment_tx {
1098 writer.write_all(&[1; 1])?;
1099 serialize_holder_tx!(prev_holder_tx);
1101 writer.write_all(&[0; 1])?;
1104 serialize_holder_tx!(self.current_holder_commitment_tx);
1106 writer.write_all(&byte_utils::be48_to_array(self.current_counterparty_commitment_number))?;
1107 writer.write_all(&byte_utils::be48_to_array(self.current_holder_commitment_number))?;
1109 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
1110 for payment_preimage in self.payment_preimages.values() {
1111 writer.write_all(&payment_preimage.0[..])?;
1114 writer.write_all(&byte_utils::be64_to_array(self.pending_monitor_events.len() as u64))?;
1115 for event in self.pending_monitor_events.iter() {
1117 MonitorEvent::HTLCEvent(upd) => {
1121 MonitorEvent::CommitmentTxBroadcasted(_) => 1u8.write(writer)?
1125 writer.write_all(&byte_utils::be64_to_array(self.pending_events.len() as u64))?;
1126 for event in self.pending_events.iter() {
1127 event.write(writer)?;
1130 self.last_block_hash.write(writer)?;
1132 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_waiting_threshold_conf.len() as u64))?;
1133 for (ref target, ref events) in self.onchain_events_waiting_threshold_conf.iter() {
1134 writer.write_all(&byte_utils::be32_to_array(**target))?;
1135 writer.write_all(&byte_utils::be64_to_array(events.len() as u64))?;
1136 for ev in events.iter() {
1138 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1140 htlc_update.0.write(writer)?;
1141 htlc_update.1.write(writer)?;
1143 OnchainEvent::MaturingOutput { ref descriptor } => {
1145 descriptor.write(writer)?;
1151 (self.outputs_to_watch.len() as u64).write(writer)?;
1152 for (txid, output_scripts) in self.outputs_to_watch.iter() {
1153 txid.write(writer)?;
1154 (output_scripts.len() as u64).write(writer)?;
1155 for script in output_scripts.iter() {
1156 script.write(writer)?;
1159 self.onchain_tx_handler.write(writer)?;
1161 self.lockdown_from_offchain.write(writer)?;
1162 self.holder_tx_signed.write(writer)?;
1168 impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
1169 pub(super) fn new(keys: ChanSigner, shutdown_pubkey: &PublicKey,
1170 on_counterparty_tx_csv: u16, destination_script: &Script, funding_info: (OutPoint, Script),
1171 counterparty_htlc_base_key: &PublicKey, counterparty_delayed_payment_base_key: &PublicKey,
1172 on_holder_tx_csv: u16, funding_redeemscript: Script, channel_value_satoshis: u64,
1173 commitment_transaction_number_obscure_factor: u64,
1174 initial_holder_commitment_tx: HolderCommitmentTransaction) -> ChannelMonitor<ChanSigner> {
1176 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
1177 let our_channel_close_key_hash = WPubkeyHash::hash(&shutdown_pubkey.serialize());
1178 let shutdown_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
1179 let payment_key_hash = WPubkeyHash::hash(&keys.pubkeys().payment_point.serialize());
1180 let counterparty_payment_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_key_hash[..]).into_script();
1182 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() };
1184 let mut onchain_tx_handler = OnchainTxHandler::new(destination_script.clone(), keys.clone(), on_holder_tx_csv);
1186 let holder_tx_sequence = initial_holder_commitment_tx.unsigned_tx.input[0].sequence as u64;
1187 let holder_tx_locktime = initial_holder_commitment_tx.unsigned_tx.lock_time as u64;
1188 let holder_commitment_tx = HolderSignedTx {
1189 txid: initial_holder_commitment_tx.txid(),
1190 revocation_key: initial_holder_commitment_tx.keys.revocation_key,
1191 a_htlc_key: initial_holder_commitment_tx.keys.broadcaster_htlc_key,
1192 b_htlc_key: initial_holder_commitment_tx.keys.countersignatory_htlc_key,
1193 delayed_payment_key: initial_holder_commitment_tx.keys.broadcaster_delayed_payment_key,
1194 per_commitment_point: initial_holder_commitment_tx.keys.per_commitment_point,
1195 feerate_per_kw: initial_holder_commitment_tx.feerate_per_kw,
1196 htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
1198 onchain_tx_handler.provide_latest_holder_tx(initial_holder_commitment_tx);
1201 latest_update_id: 0,
1202 commitment_transaction_number_obscure_factor,
1204 destination_script: destination_script.clone(),
1205 broadcasted_holder_revokable_script: None,
1206 counterparty_payment_script,
1211 current_counterparty_commitment_txid: None,
1212 prev_counterparty_commitment_txid: None,
1214 counterparty_tx_cache,
1215 funding_redeemscript,
1216 channel_value_satoshis: channel_value_satoshis,
1217 their_cur_revocation_points: None,
1221 commitment_secrets: CounterpartyCommitmentSecrets::new(),
1222 counterparty_claimable_outpoints: HashMap::new(),
1223 counterparty_commitment_txn_on_chain: HashMap::new(),
1224 counterparty_hash_commitment_number: HashMap::new(),
1226 prev_holder_signed_commitment_tx: None,
1227 current_holder_commitment_tx: holder_commitment_tx,
1228 current_counterparty_commitment_number: 1 << 48,
1229 current_holder_commitment_number: 0xffff_ffff_ffff - ((((holder_tx_sequence & 0xffffff) << 3*8) | (holder_tx_locktime as u64 & 0xffffff)) ^ commitment_transaction_number_obscure_factor),
1231 payment_preimages: HashMap::new(),
1232 pending_monitor_events: Vec::new(),
1233 pending_events: Vec::new(),
1235 onchain_events_waiting_threshold_conf: HashMap::new(),
1236 outputs_to_watch: HashMap::new(),
1240 lockdown_from_offchain: false,
1241 holder_tx_signed: false,
1243 last_block_hash: Default::default(),
1244 secp_ctx: Secp256k1::new(),
1248 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
1249 /// needed by holder commitment transactions HTCLs nor by counterparty ones. Unless we haven't already seen
1250 /// counterparty commitment transaction's secret, they are de facto pruned (we can use revocation key).
1251 pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
1252 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
1253 return Err(MonitorUpdateError("Previous secret did not match new one"));
1256 // Prune HTLCs from the previous counterparty commitment tx so we don't generate failure/fulfill
1257 // events for now-revoked/fulfilled HTLCs.
1258 if let Some(txid) = self.prev_counterparty_commitment_txid.take() {
1259 for &mut (_, ref mut source) in self.counterparty_claimable_outpoints.get_mut(&txid).unwrap() {
1264 if !self.payment_preimages.is_empty() {
1265 let cur_holder_signed_commitment_tx = &self.current_holder_commitment_tx;
1266 let prev_holder_signed_commitment_tx = self.prev_holder_signed_commitment_tx.as_ref();
1267 let min_idx = self.get_min_seen_secret();
1268 let counterparty_hash_commitment_number = &mut self.counterparty_hash_commitment_number;
1270 self.payment_preimages.retain(|&k, _| {
1271 for &(ref htlc, _, _) in cur_holder_signed_commitment_tx.htlc_outputs.iter() {
1272 if k == htlc.payment_hash {
1276 if let Some(prev_holder_commitment_tx) = prev_holder_signed_commitment_tx {
1277 for &(ref htlc, _, _) in prev_holder_commitment_tx.htlc_outputs.iter() {
1278 if k == htlc.payment_hash {
1283 let contains = if let Some(cn) = counterparty_hash_commitment_number.get(&k) {
1290 counterparty_hash_commitment_number.remove(&k);
1299 /// Informs this monitor of the latest counterparty (ie non-broadcastable) commitment transaction.
1300 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
1301 /// possibly future revocation/preimage information) to claim outputs where possible.
1302 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
1303 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 {
1304 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
1305 // so that a remote monitor doesn't learn anything unless there is a malicious close.
1306 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
1308 for &(ref htlc, _) in &htlc_outputs {
1309 self.counterparty_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
1312 let new_txid = unsigned_commitment_tx.txid();
1313 log_trace!(logger, "Tracking new counterparty commitment transaction with txid {} at commitment number {} with {} HTLC outputs", new_txid, commitment_number, htlc_outputs.len());
1314 log_trace!(logger, "New potential counterparty commitment transaction: {}", encode::serialize_hex(unsigned_commitment_tx));
1315 self.prev_counterparty_commitment_txid = self.current_counterparty_commitment_txid.take();
1316 self.current_counterparty_commitment_txid = Some(new_txid);
1317 self.counterparty_claimable_outpoints.insert(new_txid, htlc_outputs.clone());
1318 self.current_counterparty_commitment_number = commitment_number;
1319 //TODO: Merge this into the other per-counterparty-transaction output storage stuff
1320 match self.their_cur_revocation_points {
1321 Some(old_points) => {
1322 if old_points.0 == commitment_number + 1 {
1323 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
1324 } else if old_points.0 == commitment_number + 2 {
1325 if let Some(old_second_point) = old_points.2 {
1326 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
1328 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1331 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1335 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1338 let mut htlcs = Vec::with_capacity(htlc_outputs.len());
1339 for htlc in htlc_outputs {
1340 if htlc.0.transaction_output_index.is_some() {
1344 self.counterparty_tx_cache.per_htlc.insert(new_txid, htlcs);
1347 /// Informs this monitor of the latest holder (ie broadcastable) commitment transaction. The
1348 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
1349 /// is important that any clones of this channel monitor (including remote clones) by kept
1350 /// up-to-date as our holder commitment transaction is updated.
1351 /// Panics if set_on_holder_tx_csv has never been called.
1352 pub(super) fn provide_latest_holder_commitment_tx_info(&mut self, commitment_tx: HolderCommitmentTransaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), MonitorUpdateError> {
1353 let txid = commitment_tx.txid();
1354 let sequence = commitment_tx.unsigned_tx.input[0].sequence as u64;
1355 let locktime = commitment_tx.unsigned_tx.lock_time as u64;
1356 let mut new_holder_commitment_tx = HolderSignedTx {
1358 revocation_key: commitment_tx.keys.revocation_key,
1359 a_htlc_key: commitment_tx.keys.broadcaster_htlc_key,
1360 b_htlc_key: commitment_tx.keys.countersignatory_htlc_key,
1361 delayed_payment_key: commitment_tx.keys.broadcaster_delayed_payment_key,
1362 per_commitment_point: commitment_tx.keys.per_commitment_point,
1363 feerate_per_kw: commitment_tx.feerate_per_kw,
1364 htlc_outputs: htlc_outputs,
1366 self.onchain_tx_handler.provide_latest_holder_tx(commitment_tx);
1367 self.current_holder_commitment_number = 0xffff_ffff_ffff - ((((sequence & 0xffffff) << 3*8) | (locktime as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
1368 mem::swap(&mut new_holder_commitment_tx, &mut self.current_holder_commitment_tx);
1369 self.prev_holder_signed_commitment_tx = Some(new_holder_commitment_tx);
1370 if self.holder_tx_signed {
1371 return Err(MonitorUpdateError("Latest holder commitment signed has already been signed, update is rejected"));
1376 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
1377 /// commitment_tx_infos which contain the payment hash have been revoked.
1378 pub(super) fn provide_payment_preimage(&mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage) {
1379 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
1382 pub(super) fn broadcast_latest_holder_commitment_txn<B: Deref, L: Deref>(&mut self, broadcaster: &B, logger: &L)
1383 where B::Target: BroadcasterInterface,
1386 for tx in self.get_latest_holder_commitment_txn(logger).iter() {
1387 broadcaster.broadcast_transaction(tx);
1389 self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0));
1392 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
1395 /// panics if the given update is not the next update by update_id.
1396 pub fn update_monitor<B: Deref, L: Deref>(&mut self, mut updates: ChannelMonitorUpdate, broadcaster: &B, logger: &L) -> Result<(), MonitorUpdateError>
1397 where B::Target: BroadcasterInterface,
1400 if self.latest_update_id + 1 != updates.update_id {
1401 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
1403 for update in updates.updates.drain(..) {
1405 ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { commitment_tx, htlc_outputs } => {
1406 if self.lockdown_from_offchain { panic!(); }
1407 self.provide_latest_holder_commitment_tx_info(commitment_tx, htlc_outputs)?
1409 ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
1410 self.provide_latest_counterparty_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point, logger),
1411 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
1412 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
1413 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
1414 self.provide_secret(idx, secret)?,
1415 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
1416 self.lockdown_from_offchain = true;
1417 if should_broadcast {
1418 self.broadcast_latest_holder_commitment_txn(broadcaster, logger);
1420 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");
1425 self.latest_update_id = updates.update_id;
1429 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
1431 pub fn get_latest_update_id(&self) -> u64 {
1432 self.latest_update_id
1435 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
1436 pub fn get_funding_txo(&self) -> &(OutPoint, Script) {
1440 /// Gets a list of txids, with their output scripts (in the order they appear in the
1441 /// transaction), which we must learn about spends of via block_connected().
1443 /// (C-not exported) because we have no HashMap bindings
1444 pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<Script>> {
1445 &self.outputs_to_watch
1448 /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
1449 /// Generally useful when deserializing as during normal operation the return values of
1450 /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
1451 /// that the get_funding_txo outpoint and transaction must also be monitored for!).
1453 /// (C-not exported) as there is no practical way to track lifetimes of returned values.
1454 pub fn get_monitored_outpoints(&self) -> Vec<(Txid, u32, &Script)> {
1455 let mut res = Vec::with_capacity(self.counterparty_commitment_txn_on_chain.len() * 2);
1456 for (ref txid, &(_, ref outputs)) in self.counterparty_commitment_txn_on_chain.iter() {
1457 for (idx, output) in outputs.iter().enumerate() {
1458 res.push(((*txid).clone(), idx as u32, output));
1464 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1465 /// ChannelManager via [`chain::Watch::release_pending_monitor_events`].
1467 /// [`chain::Watch::release_pending_monitor_events`]: ../../chain/trait.Watch.html#tymethod.release_pending_monitor_events
1468 pub fn get_and_clear_pending_monitor_events(&mut self) -> Vec<MonitorEvent> {
1469 let mut ret = Vec::new();
1470 mem::swap(&mut ret, &mut self.pending_monitor_events);
1474 /// Gets the list of pending events which were generated by previous actions, clearing the list
1477 /// This is called by SimpleManyChannelMonitor::get_and_clear_pending_events() and is equivalent to
1478 /// EventsProvider::get_and_clear_pending_events() except that it requires &mut self as we do
1479 /// no internal locking in ChannelMonitors.
1480 pub fn get_and_clear_pending_events(&mut self) -> Vec<Event> {
1481 let mut ret = Vec::new();
1482 mem::swap(&mut ret, &mut self.pending_events);
1486 /// Can only fail if idx is < get_min_seen_secret
1487 pub(super) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
1488 self.commitment_secrets.get_secret(idx)
1491 pub(super) fn get_min_seen_secret(&self) -> u64 {
1492 self.commitment_secrets.get_min_seen_secret()
1495 pub(super) fn get_cur_counterparty_commitment_number(&self) -> u64 {
1496 self.current_counterparty_commitment_number
1499 pub(super) fn get_cur_holder_commitment_number(&self) -> u64 {
1500 self.current_holder_commitment_number
1503 /// Attempts to claim a counterparty commitment transaction's outputs using the revocation key and
1504 /// data in counterparty_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
1505 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
1506 /// HTLC-Success/HTLC-Timeout transactions.
1507 /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
1508 /// revoked counterparty commitment tx
1509 fn check_spend_counterparty_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) where L::Target: Logger {
1510 // Most secp and related errors trying to create keys means we have no hope of constructing
1511 // a spend transaction...so we return no transactions to broadcast
1512 let mut claimable_outpoints = Vec::new();
1513 let mut watch_outputs = Vec::new();
1515 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1516 let per_commitment_option = self.counterparty_claimable_outpoints.get(&commitment_txid);
1518 macro_rules! ignore_error {
1519 ( $thing : expr ) => {
1522 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs))
1527 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);
1528 if commitment_number >= self.get_min_seen_secret() {
1529 let secret = self.get_secret(commitment_number).unwrap();
1530 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1531 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1532 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.keys.pubkeys().revocation_basepoint));
1533 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));
1535 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.counterparty_tx_cache.on_counterparty_tx_csv, &delayed_key);
1536 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1538 // First, process non-htlc outputs (to_holder & to_counterparty)
1539 for (idx, outp) in tx.output.iter().enumerate() {
1540 if outp.script_pubkey == revokeable_p2wsh {
1541 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};
1542 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});
1546 // Then, try to find revoked htlc outputs
1547 if let Some(ref per_commitment_data) = per_commitment_option {
1548 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1549 if let Some(transaction_output_index) = htlc.transaction_output_index {
1550 if transaction_output_index as usize >= tx.output.len() ||
1551 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1552 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1554 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};
1555 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable: true, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1560 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
1561 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
1562 // We're definitely a counterparty commitment transaction!
1563 log_trace!(logger, "Got broadcast of revoked counterparty commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
1564 watch_outputs.append(&mut tx.output.clone());
1565 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1567 macro_rules! check_htlc_fails {
1568 ($txid: expr, $commitment_tx: expr) => {
1569 if let Some(ref outpoints) = self.counterparty_claimable_outpoints.get($txid) {
1570 for &(ref htlc, ref source_option) in outpoints.iter() {
1571 if let &Some(ref source) = source_option {
1572 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), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1573 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1574 hash_map::Entry::Occupied(mut entry) => {
1575 let e = entry.get_mut();
1576 e.retain(|ref event| {
1578 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1579 return htlc_update.0 != **source
1584 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1586 hash_map::Entry::Vacant(entry) => {
1587 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1595 if let Some(ref txid) = self.current_counterparty_commitment_txid {
1596 check_htlc_fails!(txid, "current");
1598 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
1599 check_htlc_fails!(txid, "counterparty");
1601 // No need to check holder commitment txn, symmetric HTLCSource must be present as per-htlc data on counterparty commitment tx
1603 } else if let Some(per_commitment_data) = per_commitment_option {
1604 // While this isn't useful yet, there is a potential race where if a counterparty
1605 // revokes a state at the same time as the commitment transaction for that state is
1606 // confirmed, and the watchtower receives the block before the user, the user could
1607 // upload a new ChannelMonitor with the revocation secret but the watchtower has
1608 // already processed the block, resulting in the counterparty_commitment_txn_on_chain entry
1609 // not being generated by the above conditional. Thus, to be safe, we go ahead and
1611 watch_outputs.append(&mut tx.output.clone());
1612 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1614 log_trace!(logger, "Got broadcast of non-revoked counterparty commitment transaction {}", commitment_txid);
1616 macro_rules! check_htlc_fails {
1617 ($txid: expr, $commitment_tx: expr, $id: tt) => {
1618 if let Some(ref latest_outpoints) = self.counterparty_claimable_outpoints.get($txid) {
1619 $id: for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1620 if let &Some(ref source) = source_option {
1621 // Check if the HTLC is present in the commitment transaction that was
1622 // broadcast, but not if it was below the dust limit, which we should
1623 // fail backwards immediately as there is no way for us to learn the
1624 // payment_preimage.
1625 // Note that if the dust limit were allowed to change between
1626 // commitment transactions we'd want to be check whether *any*
1627 // broadcastable commitment transaction has the HTLC in it, but it
1628 // cannot currently change after channel initialization, so we don't
1630 for &(ref broadcast_htlc, ref broadcast_source) in per_commitment_data.iter() {
1631 if broadcast_htlc.transaction_output_index.is_some() && Some(source) == broadcast_source.as_ref() {
1635 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);
1636 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1637 hash_map::Entry::Occupied(mut entry) => {
1638 let e = entry.get_mut();
1639 e.retain(|ref event| {
1641 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1642 return htlc_update.0 != **source
1647 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1649 hash_map::Entry::Vacant(entry) => {
1650 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1658 if let Some(ref txid) = self.current_counterparty_commitment_txid {
1659 check_htlc_fails!(txid, "current", 'current_loop);
1661 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
1662 check_htlc_fails!(txid, "previous", 'prev_loop);
1665 if let Some(revocation_points) = self.their_cur_revocation_points {
1666 let revocation_point_option =
1667 if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1668 else if let Some(point) = revocation_points.2.as_ref() {
1669 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1671 if let Some(revocation_point) = revocation_point_option {
1672 self.counterparty_payment_script = {
1673 // Note that the Network here is ignored as we immediately drop the address for the
1674 // script_pubkey version
1675 let payment_hash160 = WPubkeyHash::hash(&self.keys.pubkeys().payment_point.serialize());
1676 Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_hash160[..]).into_script()
1679 // Then, try to find htlc outputs
1680 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1681 if let Some(transaction_output_index) = htlc.transaction_output_index {
1682 if transaction_output_index as usize >= tx.output.len() ||
1683 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1684 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1686 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
1687 let aggregable = if !htlc.offered { false } else { true };
1688 if preimage.is_some() || !htlc.offered {
1689 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() };
1690 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1697 (claimable_outpoints, (commitment_txid, watch_outputs))
1700 /// Attempts to claim a counterparty HTLC-Success/HTLC-Timeout's outputs using the revocation key
1701 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 {
1702 let htlc_txid = tx.txid();
1703 if tx.input.len() != 1 || tx.output.len() != 1 || tx.input[0].witness.len() != 5 {
1704 return (Vec::new(), None)
1707 macro_rules! ignore_error {
1708 ( $thing : expr ) => {
1711 Err(_) => return (Vec::new(), None)
1716 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
1717 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1718 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1720 log_trace!(logger, "Counterparty HTLC broadcast {}:{}", htlc_txid, 0);
1721 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 };
1722 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 });
1723 (claimable_outpoints, Some((htlc_txid, tx.output.clone())))
1726 fn broadcast_by_holder_state(&self, commitment_tx: &Transaction, holder_tx: &HolderSignedTx) -> (Vec<ClaimRequest>, Vec<TxOut>, Option<(Script, PublicKey, PublicKey)>) {
1727 let mut claim_requests = Vec::with_capacity(holder_tx.htlc_outputs.len());
1728 let mut watch_outputs = Vec::with_capacity(holder_tx.htlc_outputs.len());
1730 let redeemscript = chan_utils::get_revokeable_redeemscript(&holder_tx.revocation_key, self.on_holder_tx_csv, &holder_tx.delayed_payment_key);
1731 let broadcasted_holder_revokable_script = Some((redeemscript.to_v0_p2wsh(), holder_tx.per_commitment_point.clone(), holder_tx.revocation_key.clone()));
1733 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
1734 if let Some(transaction_output_index) = htlc.transaction_output_index {
1735 claim_requests.push(ClaimRequest { absolute_timelock: ::std::u32::MAX, aggregable: false, outpoint: BitcoinOutPoint { txid: holder_tx.txid, vout: transaction_output_index as u32 },
1736 witness_data: InputMaterial::HolderHTLC {
1737 preimage: if !htlc.offered {
1738 if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1739 Some(preimage.clone())
1741 // We can't build an HTLC-Success transaction without the preimage
1745 amount: htlc.amount_msat,
1747 watch_outputs.push(commitment_tx.output[transaction_output_index as usize].clone());
1751 (claim_requests, watch_outputs, broadcasted_holder_revokable_script)
1754 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1755 /// revoked using data in holder_claimable_outpoints.
1756 /// Should not be used if check_spend_revoked_transaction succeeds.
1757 fn check_spend_holder_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) where L::Target: Logger {
1758 let commitment_txid = tx.txid();
1759 let mut claim_requests = Vec::new();
1760 let mut watch_outputs = Vec::new();
1762 macro_rules! wait_threshold_conf {
1763 ($height: expr, $source: expr, $commitment_tx: expr, $payment_hash: expr) => {
1764 log_trace!(logger, "Failing HTLC with payment_hash {} from {} holder commitment tx due to broadcast of transaction, waiting confirmation (at height{})", log_bytes!($payment_hash.0), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1765 match self.onchain_events_waiting_threshold_conf.entry($height + ANTI_REORG_DELAY - 1) {
1766 hash_map::Entry::Occupied(mut entry) => {
1767 let e = entry.get_mut();
1768 e.retain(|ref event| {
1770 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1771 return htlc_update.0 != $source
1776 e.push(OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)});
1778 hash_map::Entry::Vacant(entry) => {
1779 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)}]);
1785 macro_rules! append_onchain_update {
1786 ($updates: expr) => {
1787 claim_requests = $updates.0;
1788 watch_outputs.append(&mut $updates.1);
1789 self.broadcasted_holder_revokable_script = $updates.2;
1793 // HTLCs set may differ between last and previous holder commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
1794 let mut is_holder_tx = false;
1796 if self.current_holder_commitment_tx.txid == commitment_txid {
1797 is_holder_tx = true;
1798 log_trace!(logger, "Got latest holder commitment tx broadcast, searching for available HTLCs to claim");
1799 let mut res = self.broadcast_by_holder_state(tx, &self.current_holder_commitment_tx);
1800 append_onchain_update!(res);
1801 } else if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
1802 if holder_tx.txid == commitment_txid {
1803 is_holder_tx = true;
1804 log_trace!(logger, "Got previous holder commitment tx broadcast, searching for available HTLCs to claim");
1805 let mut res = self.broadcast_by_holder_state(tx, holder_tx);
1806 append_onchain_update!(res);
1810 macro_rules! fail_dust_htlcs_after_threshold_conf {
1811 ($holder_tx: expr) => {
1812 for &(ref htlc, _, ref source) in &$holder_tx.htlc_outputs {
1813 if htlc.transaction_output_index.is_none() {
1814 if let &Some(ref source) = source {
1815 wait_threshold_conf!(height, source.clone(), "lastest", htlc.payment_hash.clone());
1823 fail_dust_htlcs_after_threshold_conf!(self.current_holder_commitment_tx);
1824 if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
1825 fail_dust_htlcs_after_threshold_conf!(holder_tx);
1829 (claim_requests, (commitment_txid, watch_outputs))
1832 /// Used by ChannelManager deserialization to broadcast the latest holder state if its copy of
1833 /// the Channel was out-of-date. You may use it to get a broadcastable holder toxic tx in case of
1834 /// fallen-behind, i.e when receiving a channel_reestablish with a proof that our counterparty side knows
1835 /// a higher revocation secret than the holder commitment number we are aware of. Broadcasting these
1836 /// transactions are UNSAFE, as they allow counterparty side to punish you. Nevertheless you may want to
1837 /// broadcast them if counterparty don't close channel with his higher commitment transaction after a
1838 /// substantial amount of time (a month or even a year) to get back funds. Best may be to contact
1839 /// out-of-band the other node operator to coordinate with him if option is available to you.
1840 /// In any-case, choice is up to the user.
1841 pub fn get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1842 log_trace!(logger, "Getting signed latest holder commitment transaction!");
1843 self.holder_tx_signed = true;
1844 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript) {
1845 let txid = commitment_tx.txid();
1846 let mut res = vec![commitment_tx];
1847 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
1848 if let Some(vout) = htlc.0.transaction_output_index {
1849 let preimage = if !htlc.0.offered {
1850 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1851 // We can't build an HTLC-Success transaction without the preimage
1855 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
1856 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1861 // 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.
1862 // The data will be re-generated and tracked in check_spend_holder_transaction if we get a confirmation.
1868 /// Unsafe test-only version of get_latest_holder_commitment_txn used by our test framework
1869 /// to bypass HolderCommitmentTransaction state update lockdown after signature and generate
1870 /// revoked commitment transaction.
1871 #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]
1872 pub fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1873 log_trace!(logger, "Getting signed copy of latest holder commitment transaction!");
1874 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_copy_holder_tx(&self.funding_redeemscript) {
1875 let txid = commitment_tx.txid();
1876 let mut res = vec![commitment_tx];
1877 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
1878 if let Some(vout) = htlc.0.transaction_output_index {
1879 let preimage = if !htlc.0.offered {
1880 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1881 // We can't build an HTLC-Success transaction without the preimage
1885 if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
1886 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1896 /// Processes transactions in a newly connected block, which may result in any of the following:
1897 /// - update the monitor's state against resolved HTLCs
1898 /// - punish the counterparty in the case of seeing a revoked commitment transaction
1899 /// - force close the channel and claim/timeout incoming/outgoing HTLCs if near expiration
1900 /// - detect settled outputs for later spending
1901 /// - schedule and bump any in-flight claims
1903 /// Returns any transaction outputs from `txn_matched` that spends of should be watched for.
1904 /// After called these are also available via [`get_outputs_to_watch`].
1906 /// [`get_outputs_to_watch`]: #method.get_outputs_to_watch
1907 pub 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>)>
1908 where B::Target: BroadcasterInterface,
1909 F::Target: FeeEstimator,
1912 for &(_, tx) in txn_matched {
1913 let mut output_val = 0;
1914 for out in tx.output.iter() {
1915 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1916 output_val += out.value;
1917 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1921 let block_hash = header.block_hash();
1922 log_trace!(logger, "Block {} at height {} connected with {} txn matched", block_hash, height, txn_matched.len());
1924 let mut watch_outputs = Vec::new();
1925 let mut claimable_outpoints = Vec::new();
1926 for &(_, tx) in txn_matched {
1927 if tx.input.len() == 1 {
1928 // Assuming our keys were not leaked (in which case we're screwed no matter what),
1929 // commitment transactions and HTLC transactions will all only ever have one input,
1930 // which is an easy way to filter out any potential non-matching txn for lazy
1932 let prevout = &tx.input[0].previous_output;
1933 if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
1934 if (tx.input[0].sequence >> 8*3) as u8 == 0x80 && (tx.lock_time >> 8*3) as u8 == 0x20 {
1935 let (mut new_outpoints, new_outputs) = self.check_spend_counterparty_transaction(&tx, height, &logger);
1936 if !new_outputs.1.is_empty() {
1937 watch_outputs.push(new_outputs);
1939 if new_outpoints.is_empty() {
1940 let (mut new_outpoints, new_outputs) = self.check_spend_holder_transaction(&tx, height, &logger);
1941 if !new_outputs.1.is_empty() {
1942 watch_outputs.push(new_outputs);
1944 claimable_outpoints.append(&mut new_outpoints);
1946 claimable_outpoints.append(&mut new_outpoints);
1949 if let Some(&(commitment_number, _)) = self.counterparty_commitment_txn_on_chain.get(&prevout.txid) {
1950 let (mut new_outpoints, new_outputs_option) = self.check_spend_counterparty_htlc(&tx, commitment_number, height, &logger);
1951 claimable_outpoints.append(&mut new_outpoints);
1952 if let Some(new_outputs) = new_outputs_option {
1953 watch_outputs.push(new_outputs);
1958 // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
1959 // can also be resolved in a few other ways which can have more than one output. Thus,
1960 // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
1961 self.is_resolving_htlc_output(&tx, height, &logger);
1963 self.is_paying_spendable_output(&tx, height, &logger);
1965 let should_broadcast = self.would_broadcast_at_height(height, &logger);
1966 if should_broadcast {
1967 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() }});
1969 if should_broadcast {
1970 self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0));
1971 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript) {
1972 self.holder_tx_signed = true;
1973 let (mut new_outpoints, new_outputs, _) = self.broadcast_by_holder_state(&commitment_tx, &self.current_holder_commitment_tx);
1974 if !new_outputs.is_empty() {
1975 watch_outputs.push((self.current_holder_commitment_tx.txid.clone(), new_outputs));
1977 claimable_outpoints.append(&mut new_outpoints);
1980 if let Some(events) = self.onchain_events_waiting_threshold_conf.remove(&height) {
1983 OnchainEvent::HTLCUpdate { htlc_update } => {
1984 log_trace!(logger, "HTLC {} failure update has got enough confirmations to be passed upstream", log_bytes!((htlc_update.1).0));
1985 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
1986 payment_hash: htlc_update.1,
1987 payment_preimage: None,
1988 source: htlc_update.0,
1991 OnchainEvent::MaturingOutput { descriptor } => {
1992 log_trace!(logger, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
1993 self.pending_events.push(Event::SpendableOutputs {
1994 outputs: vec![descriptor]
2001 self.onchain_tx_handler.block_connected(txn_matched, claimable_outpoints, height, &*broadcaster, &*fee_estimator, &*logger);
2003 self.last_block_hash = block_hash;
2004 for &(ref txid, ref output_scripts) in watch_outputs.iter() {
2005 self.outputs_to_watch.insert(txid.clone(), output_scripts.iter().map(|o| o.script_pubkey.clone()).collect());
2011 /// Determines if the disconnected block contained any transactions of interest and updates
2013 pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, height: u32, broadcaster: B, fee_estimator: F, logger: L)
2014 where B::Target: BroadcasterInterface,
2015 F::Target: FeeEstimator,
2018 let block_hash = header.block_hash();
2019 log_trace!(logger, "Block {} at height {} disconnected", block_hash, height);
2021 if let Some(_) = self.onchain_events_waiting_threshold_conf.remove(&(height + ANTI_REORG_DELAY - 1)) {
2023 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
2024 //- maturing spendable output has transaction paying us has been disconnected
2027 self.onchain_tx_handler.block_disconnected(height, broadcaster, fee_estimator, logger);
2029 self.last_block_hash = block_hash;
2032 fn would_broadcast_at_height<L: Deref>(&self, height: u32, logger: &L) -> bool where L::Target: Logger {
2033 // We need to consider all HTLCs which are:
2034 // * in any unrevoked counterparty commitment transaction, as they could broadcast said
2035 // transactions and we'd end up in a race, or
2036 // * are in our latest holder commitment transaction, as this is the thing we will
2037 // broadcast if we go on-chain.
2038 // Note that we consider HTLCs which were below dust threshold here - while they don't
2039 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
2040 // to the source, and if we don't fail the channel we will have to ensure that the next
2041 // updates that peer sends us are update_fails, failing the channel if not. It's probably
2042 // easier to just fail the channel as this case should be rare enough anyway.
2043 macro_rules! scan_commitment {
2044 ($htlcs: expr, $holder_tx: expr) => {
2045 for ref htlc in $htlcs {
2046 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
2047 // chain with enough room to claim the HTLC without our counterparty being able to
2048 // time out the HTLC first.
2049 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
2050 // concern is being able to claim the corresponding inbound HTLC (on another
2051 // channel) before it expires. In fact, we don't even really care if our
2052 // counterparty here claims such an outbound HTLC after it expired as long as we
2053 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
2054 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
2055 // we give ourselves a few blocks of headroom after expiration before going
2056 // on-chain for an expired HTLC.
2057 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
2058 // from us until we've reached the point where we go on-chain with the
2059 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
2060 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
2061 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
2062 // inbound_cltv == height + CLTV_CLAIM_BUFFER
2063 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
2064 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
2065 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
2066 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
2067 // The final, above, condition is checked for statically in channelmanager
2068 // with CHECK_CLTV_EXPIRY_SANITY_2.
2069 let htlc_outbound = $holder_tx == htlc.offered;
2070 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
2071 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
2072 log_info!(logger, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
2079 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
2081 if let Some(ref txid) = self.current_counterparty_commitment_txid {
2082 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
2083 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2086 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
2087 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
2088 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2095 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a holder
2096 /// or counterparty commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
2097 fn is_resolving_htlc_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2098 'outer_loop: for input in &tx.input {
2099 let mut payment_data = None;
2100 let revocation_sig_claim = (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && input.witness[1].len() == 33)
2101 || (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && input.witness[1].len() == 33);
2102 let accepted_preimage_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::AcceptedHTLC);
2103 let offered_preimage_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC);
2105 macro_rules! log_claim {
2106 ($tx_info: expr, $holder_tx: expr, $htlc: expr, $source_avail: expr) => {
2107 // We found the output in question, but aren't failing it backwards
2108 // as we have no corresponding source and no valid counterparty commitment txid
2109 // to try a weak source binding with same-hash, same-value still-valid offered HTLC.
2110 // This implies either it is an inbound HTLC or an outbound HTLC on a revoked transaction.
2111 let outbound_htlc = $holder_tx == $htlc.offered;
2112 if ($holder_tx && revocation_sig_claim) ||
2113 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
2114 log_error!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
2115 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2116 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2117 if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back" });
2119 log_info!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
2120 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2121 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2122 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
2127 macro_rules! check_htlc_valid_counterparty {
2128 ($counterparty_txid: expr, $htlc_output: expr) => {
2129 if let Some(txid) = $counterparty_txid {
2130 for &(ref pending_htlc, ref pending_source) in self.counterparty_claimable_outpoints.get(&txid).unwrap() {
2131 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
2132 if let &Some(ref source) = pending_source {
2133 log_claim!("revoked counterparty commitment tx", false, pending_htlc, true);
2134 payment_data = Some(((**source).clone(), $htlc_output.payment_hash));
2143 macro_rules! scan_commitment {
2144 ($htlcs: expr, $tx_info: expr, $holder_tx: expr) => {
2145 for (ref htlc_output, source_option) in $htlcs {
2146 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
2147 if let Some(ref source) = source_option {
2148 log_claim!($tx_info, $holder_tx, htlc_output, true);
2149 // We have a resolution of an HTLC either from one of our latest
2150 // holder commitment transactions or an unrevoked counterparty commitment
2151 // transaction. This implies we either learned a preimage, the HTLC
2152 // has timed out, or we screwed up. In any case, we should now
2153 // resolve the source HTLC with the original sender.
2154 payment_data = Some(((*source).clone(), htlc_output.payment_hash));
2155 } else if !$holder_tx {
2156 check_htlc_valid_counterparty!(self.current_counterparty_commitment_txid, htlc_output);
2157 if payment_data.is_none() {
2158 check_htlc_valid_counterparty!(self.prev_counterparty_commitment_txid, htlc_output);
2161 if payment_data.is_none() {
2162 log_claim!($tx_info, $holder_tx, htlc_output, false);
2163 continue 'outer_loop;
2170 if input.previous_output.txid == self.current_holder_commitment_tx.txid {
2171 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2172 "our latest holder commitment tx", true);
2174 if let Some(ref prev_holder_signed_commitment_tx) = self.prev_holder_signed_commitment_tx {
2175 if input.previous_output.txid == prev_holder_signed_commitment_tx.txid {
2176 scan_commitment!(prev_holder_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2177 "our previous holder commitment tx", true);
2180 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(&input.previous_output.txid) {
2181 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
2182 "counterparty commitment tx", false);
2185 // Check that scan_commitment, above, decided there is some source worth relaying an
2186 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
2187 if let Some((source, payment_hash)) = payment_data {
2188 let mut payment_preimage = PaymentPreimage([0; 32]);
2189 if accepted_preimage_claim {
2190 if !self.pending_monitor_events.iter().any(
2191 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update { upd.source == source } else { false }) {
2192 payment_preimage.0.copy_from_slice(&input.witness[3]);
2193 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2195 payment_preimage: Some(payment_preimage),
2199 } else if offered_preimage_claim {
2200 if !self.pending_monitor_events.iter().any(
2201 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update {
2202 upd.source == source
2204 payment_preimage.0.copy_from_slice(&input.witness[1]);
2205 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2207 payment_preimage: Some(payment_preimage),
2212 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);
2213 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2214 hash_map::Entry::Occupied(mut entry) => {
2215 let e = entry.get_mut();
2216 e.retain(|ref event| {
2218 OnchainEvent::HTLCUpdate { ref htlc_update } => {
2219 return htlc_update.0 != source
2224 e.push(OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)});
2226 hash_map::Entry::Vacant(entry) => {
2227 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)}]);
2235 /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
2236 fn is_paying_spendable_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2237 let mut spendable_output = None;
2238 for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
2239 if i > ::std::u16::MAX as usize {
2240 // While it is possible that an output exists on chain which is greater than the
2241 // 2^16th output in a given transaction, this is only possible if the output is not
2242 // in a lightning transaction and was instead placed there by some third party who
2243 // wishes to give us money for no reason.
2244 // Namely, any lightning transactions which we pre-sign will never have anywhere
2245 // near 2^16 outputs both because such transactions must have ~2^16 outputs who's
2246 // scripts are not longer than one byte in length and because they are inherently
2247 // non-standard due to their size.
2248 // Thus, it is completely safe to ignore such outputs, and while it may result in
2249 // us ignoring non-lightning fund to us, that is only possible if someone fills
2250 // nearly a full block with garbage just to hit this case.
2253 if outp.script_pubkey == self.destination_script {
2254 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2255 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2256 output: outp.clone(),
2259 } else if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
2260 if broadcasted_holder_revokable_script.0 == outp.script_pubkey {
2261 spendable_output = Some(SpendableOutputDescriptor::DynamicOutputP2WSH {
2262 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2263 per_commitment_point: broadcasted_holder_revokable_script.1,
2264 to_self_delay: self.on_holder_tx_csv,
2265 output: outp.clone(),
2266 key_derivation_params: self.keys.key_derivation_params(),
2267 revocation_pubkey: broadcasted_holder_revokable_script.2.clone(),
2271 } else if self.counterparty_payment_script == outp.script_pubkey {
2272 spendable_output = Some(SpendableOutputDescriptor::StaticOutputCounterpartyPayment {
2273 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2274 output: outp.clone(),
2275 key_derivation_params: self.keys.key_derivation_params(),
2278 } else if outp.script_pubkey == self.shutdown_script {
2279 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2280 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2281 output: outp.clone(),
2285 if let Some(spendable_output) = spendable_output {
2286 log_trace!(logger, "Maturing {} until {}", log_spendable!(spendable_output), height + ANTI_REORG_DELAY - 1);
2287 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2288 hash_map::Entry::Occupied(mut entry) => {
2289 let e = entry.get_mut();
2290 e.push(OnchainEvent::MaturingOutput { descriptor: spendable_output });
2292 hash_map::Entry::Vacant(entry) => {
2293 entry.insert(vec![OnchainEvent::MaturingOutput { descriptor: spendable_output }]);
2300 const MAX_ALLOC_SIZE: usize = 64*1024;
2302 impl<ChanSigner: ChannelKeys + Readable> Readable for (BlockHash, ChannelMonitor<ChanSigner>) {
2303 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
2304 macro_rules! unwrap_obj {
2308 Err(_) => return Err(DecodeError::InvalidValue),
2313 let _ver: u8 = Readable::read(reader)?;
2314 let min_ver: u8 = Readable::read(reader)?;
2315 if min_ver > SERIALIZATION_VERSION {
2316 return Err(DecodeError::UnknownVersion);
2319 let latest_update_id: u64 = Readable::read(reader)?;
2320 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
2322 let destination_script = Readable::read(reader)?;
2323 let broadcasted_holder_revokable_script = match <u8 as Readable>::read(reader)? {
2325 let revokable_address = Readable::read(reader)?;
2326 let per_commitment_point = Readable::read(reader)?;
2327 let revokable_script = Readable::read(reader)?;
2328 Some((revokable_address, per_commitment_point, revokable_script))
2331 _ => return Err(DecodeError::InvalidValue),
2333 let counterparty_payment_script = Readable::read(reader)?;
2334 let shutdown_script = Readable::read(reader)?;
2336 let keys = Readable::read(reader)?;
2337 // Technically this can fail and serialize fail a round-trip, but only for serialization of
2338 // barely-init'd ChannelMonitors that we can't do anything with.
2339 let outpoint = OutPoint {
2340 txid: Readable::read(reader)?,
2341 index: Readable::read(reader)?,
2343 let funding_info = (outpoint, Readable::read(reader)?);
2344 let current_counterparty_commitment_txid = Readable::read(reader)?;
2345 let prev_counterparty_commitment_txid = Readable::read(reader)?;
2347 let counterparty_tx_cache = Readable::read(reader)?;
2348 let funding_redeemscript = Readable::read(reader)?;
2349 let channel_value_satoshis = Readable::read(reader)?;
2351 let their_cur_revocation_points = {
2352 let first_idx = <U48 as Readable>::read(reader)?.0;
2356 let first_point = Readable::read(reader)?;
2357 let second_point_slice: [u8; 33] = Readable::read(reader)?;
2358 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
2359 Some((first_idx, first_point, None))
2361 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
2366 let on_holder_tx_csv: u16 = Readable::read(reader)?;
2368 let commitment_secrets = Readable::read(reader)?;
2370 macro_rules! read_htlc_in_commitment {
2373 let offered: bool = Readable::read(reader)?;
2374 let amount_msat: u64 = Readable::read(reader)?;
2375 let cltv_expiry: u32 = Readable::read(reader)?;
2376 let payment_hash: PaymentHash = Readable::read(reader)?;
2377 let transaction_output_index: Option<u32> = Readable::read(reader)?;
2379 HTLCOutputInCommitment {
2380 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
2386 let counterparty_claimable_outpoints_len: u64 = Readable::read(reader)?;
2387 let mut counterparty_claimable_outpoints = HashMap::with_capacity(cmp::min(counterparty_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
2388 for _ in 0..counterparty_claimable_outpoints_len {
2389 let txid: Txid = Readable::read(reader)?;
2390 let htlcs_count: u64 = Readable::read(reader)?;
2391 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
2392 for _ in 0..htlcs_count {
2393 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
2395 if let Some(_) = counterparty_claimable_outpoints.insert(txid, htlcs) {
2396 return Err(DecodeError::InvalidValue);
2400 let counterparty_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
2401 let mut counterparty_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(counterparty_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
2402 for _ in 0..counterparty_commitment_txn_on_chain_len {
2403 let txid: Txid = Readable::read(reader)?;
2404 let commitment_number = <U48 as Readable>::read(reader)?.0;
2405 let outputs_count = <u64 as Readable>::read(reader)?;
2406 let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 8));
2407 for _ in 0..outputs_count {
2408 outputs.push(Readable::read(reader)?);
2410 if let Some(_) = counterparty_commitment_txn_on_chain.insert(txid, (commitment_number, outputs)) {
2411 return Err(DecodeError::InvalidValue);
2415 let counterparty_hash_commitment_number_len: u64 = Readable::read(reader)?;
2416 let mut counterparty_hash_commitment_number = HashMap::with_capacity(cmp::min(counterparty_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
2417 for _ in 0..counterparty_hash_commitment_number_len {
2418 let payment_hash: PaymentHash = Readable::read(reader)?;
2419 let commitment_number = <U48 as Readable>::read(reader)?.0;
2420 if let Some(_) = counterparty_hash_commitment_number.insert(payment_hash, commitment_number) {
2421 return Err(DecodeError::InvalidValue);
2425 macro_rules! read_holder_tx {
2428 let txid = Readable::read(reader)?;
2429 let revocation_key = Readable::read(reader)?;
2430 let a_htlc_key = Readable::read(reader)?;
2431 let b_htlc_key = Readable::read(reader)?;
2432 let delayed_payment_key = Readable::read(reader)?;
2433 let per_commitment_point = Readable::read(reader)?;
2434 let feerate_per_kw: u32 = Readable::read(reader)?;
2436 let htlcs_len: u64 = Readable::read(reader)?;
2437 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_len as usize, MAX_ALLOC_SIZE / 128));
2438 for _ in 0..htlcs_len {
2439 let htlc = read_htlc_in_commitment!();
2440 let sigs = match <u8 as Readable>::read(reader)? {
2442 1 => Some(Readable::read(reader)?),
2443 _ => return Err(DecodeError::InvalidValue),
2445 htlcs.push((htlc, sigs, Readable::read(reader)?));
2450 revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, per_commitment_point, feerate_per_kw,
2457 let prev_holder_signed_commitment_tx = match <u8 as Readable>::read(reader)? {
2460 Some(read_holder_tx!())
2462 _ => return Err(DecodeError::InvalidValue),
2464 let current_holder_commitment_tx = read_holder_tx!();
2466 let current_counterparty_commitment_number = <U48 as Readable>::read(reader)?.0;
2467 let current_holder_commitment_number = <U48 as Readable>::read(reader)?.0;
2469 let payment_preimages_len: u64 = Readable::read(reader)?;
2470 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
2471 for _ in 0..payment_preimages_len {
2472 let preimage: PaymentPreimage = Readable::read(reader)?;
2473 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2474 if let Some(_) = payment_preimages.insert(hash, preimage) {
2475 return Err(DecodeError::InvalidValue);
2479 let pending_monitor_events_len: u64 = Readable::read(reader)?;
2480 let mut pending_monitor_events = Vec::with_capacity(cmp::min(pending_monitor_events_len as usize, MAX_ALLOC_SIZE / (32 + 8*3)));
2481 for _ in 0..pending_monitor_events_len {
2482 let ev = match <u8 as Readable>::read(reader)? {
2483 0 => MonitorEvent::HTLCEvent(Readable::read(reader)?),
2484 1 => MonitorEvent::CommitmentTxBroadcasted(funding_info.0),
2485 _ => return Err(DecodeError::InvalidValue)
2487 pending_monitor_events.push(ev);
2490 let pending_events_len: u64 = Readable::read(reader)?;
2491 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Event>()));
2492 for _ in 0..pending_events_len {
2493 if let Some(event) = MaybeReadable::read(reader)? {
2494 pending_events.push(event);
2498 let last_block_hash: BlockHash = Readable::read(reader)?;
2500 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
2501 let mut onchain_events_waiting_threshold_conf = HashMap::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
2502 for _ in 0..waiting_threshold_conf_len {
2503 let height_target = Readable::read(reader)?;
2504 let events_len: u64 = Readable::read(reader)?;
2505 let mut events = Vec::with_capacity(cmp::min(events_len as usize, MAX_ALLOC_SIZE / 128));
2506 for _ in 0..events_len {
2507 let ev = match <u8 as Readable>::read(reader)? {
2509 let htlc_source = Readable::read(reader)?;
2510 let hash = Readable::read(reader)?;
2511 OnchainEvent::HTLCUpdate {
2512 htlc_update: (htlc_source, hash)
2516 let descriptor = Readable::read(reader)?;
2517 OnchainEvent::MaturingOutput {
2521 _ => return Err(DecodeError::InvalidValue),
2525 onchain_events_waiting_threshold_conf.insert(height_target, events);
2528 let outputs_to_watch_len: u64 = Readable::read(reader)?;
2529 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>>())));
2530 for _ in 0..outputs_to_watch_len {
2531 let txid = Readable::read(reader)?;
2532 let outputs_len: u64 = Readable::read(reader)?;
2533 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Script>()));
2534 for _ in 0..outputs_len {
2535 outputs.push(Readable::read(reader)?);
2537 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
2538 return Err(DecodeError::InvalidValue);
2541 let onchain_tx_handler = Readable::read(reader)?;
2543 let lockdown_from_offchain = Readable::read(reader)?;
2544 let holder_tx_signed = Readable::read(reader)?;
2546 Ok((last_block_hash.clone(), ChannelMonitor {
2548 commitment_transaction_number_obscure_factor,
2551 broadcasted_holder_revokable_script,
2552 counterparty_payment_script,
2557 current_counterparty_commitment_txid,
2558 prev_counterparty_commitment_txid,
2560 counterparty_tx_cache,
2561 funding_redeemscript,
2562 channel_value_satoshis,
2563 their_cur_revocation_points,
2568 counterparty_claimable_outpoints,
2569 counterparty_commitment_txn_on_chain,
2570 counterparty_hash_commitment_number,
2572 prev_holder_signed_commitment_tx,
2573 current_holder_commitment_tx,
2574 current_counterparty_commitment_number,
2575 current_holder_commitment_number,
2578 pending_monitor_events,
2581 onchain_events_waiting_threshold_conf,
2586 lockdown_from_offchain,
2590 secp_ctx: Secp256k1::new(),
2597 use bitcoin::blockdata::script::{Script, Builder};
2598 use bitcoin::blockdata::opcodes;
2599 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, SigHashType};
2600 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
2601 use bitcoin::util::bip143;
2602 use bitcoin::hashes::Hash;
2603 use bitcoin::hashes::sha256::Hash as Sha256;
2604 use bitcoin::hashes::hex::FromHex;
2605 use bitcoin::hash_types::Txid;
2607 use chain::transaction::OutPoint;
2608 use ln::channelmanager::{PaymentPreimage, PaymentHash};
2609 use ln::channelmonitor::ChannelMonitor;
2610 use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
2612 use ln::chan_utils::{HTLCOutputInCommitment, HolderCommitmentTransaction};
2613 use util::test_utils::TestLogger;
2614 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
2615 use bitcoin::secp256k1::Secp256k1;
2617 use chain::keysinterface::InMemoryChannelKeys;
2620 fn test_prune_preimages() {
2621 let secp_ctx = Secp256k1::new();
2622 let logger = Arc::new(TestLogger::new());
2624 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
2625 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2627 let mut preimages = Vec::new();
2630 let preimage = PaymentPreimage([i; 32]);
2631 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2632 preimages.push((preimage, hash));
2636 macro_rules! preimages_slice_to_htlc_outputs {
2637 ($preimages_slice: expr) => {
2639 let mut res = Vec::new();
2640 for (idx, preimage) in $preimages_slice.iter().enumerate() {
2641 res.push((HTLCOutputInCommitment {
2645 payment_hash: preimage.1.clone(),
2646 transaction_output_index: Some(idx as u32),
2653 macro_rules! preimages_to_holder_htlcs {
2654 ($preimages_slice: expr) => {
2656 let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2657 let res: Vec<_> = inp.drain(..).map(|e| { (e.0, None, e.1) }).collect();
2663 macro_rules! test_preimages_exist {
2664 ($preimages_slice: expr, $monitor: expr) => {
2665 for preimage in $preimages_slice {
2666 assert!($monitor.payment_preimages.contains_key(&preimage.1));
2671 let keys = InMemoryChannelKeys::new(
2673 SecretKey::from_slice(&[41; 32]).unwrap(),
2674 SecretKey::from_slice(&[41; 32]).unwrap(),
2675 SecretKey::from_slice(&[41; 32]).unwrap(),
2676 SecretKey::from_slice(&[41; 32]).unwrap(),
2677 SecretKey::from_slice(&[41; 32]).unwrap(),
2683 // Prune with one old state and a holder commitment tx holding a few overlaps with the
2685 let mut monitor = ChannelMonitor::new(keys,
2686 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()), 0, &Script::new(),
2687 (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
2688 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
2689 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
2690 10, Script::new(), 46, 0, HolderCommitmentTransaction::dummy());
2692 monitor.provide_latest_holder_commitment_tx_info(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..10])).unwrap();
2693 monitor.provide_latest_counterparty_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
2694 monitor.provide_latest_counterparty_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
2695 monitor.provide_latest_counterparty_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
2696 monitor.provide_latest_counterparty_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
2697 for &(ref preimage, ref hash) in preimages.iter() {
2698 monitor.provide_payment_preimage(hash, preimage);
2701 // Now provide a secret, pruning preimages 10-15
2702 let mut secret = [0; 32];
2703 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2704 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2705 assert_eq!(monitor.payment_preimages.len(), 15);
2706 test_preimages_exist!(&preimages[0..10], monitor);
2707 test_preimages_exist!(&preimages[15..20], monitor);
2709 // Now provide a further secret, pruning preimages 15-17
2710 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2711 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2712 assert_eq!(monitor.payment_preimages.len(), 13);
2713 test_preimages_exist!(&preimages[0..10], monitor);
2714 test_preimages_exist!(&preimages[17..20], monitor);
2716 // Now update holder commitment tx info, pruning only element 18 as we still care about the
2717 // previous commitment tx's preimages too
2718 monitor.provide_latest_holder_commitment_tx_info(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..5])).unwrap();
2719 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2720 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2721 assert_eq!(monitor.payment_preimages.len(), 12);
2722 test_preimages_exist!(&preimages[0..10], monitor);
2723 test_preimages_exist!(&preimages[18..20], monitor);
2725 // But if we do it again, we'll prune 5-10
2726 monitor.provide_latest_holder_commitment_tx_info(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..3])).unwrap();
2727 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2728 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2729 assert_eq!(monitor.payment_preimages.len(), 5);
2730 test_preimages_exist!(&preimages[0..5], monitor);
2734 fn test_claim_txn_weight_computation() {
2735 // We test Claim txn weight, knowing that we want expected weigth and
2736 // not actual case to avoid sigs and time-lock delays hell variances.
2738 let secp_ctx = Secp256k1::new();
2739 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
2740 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
2741 let mut sum_actual_sigs = 0;
2743 macro_rules! sign_input {
2744 ($sighash_parts: expr, $idx: expr, $amount: expr, $input_type: expr, $sum_actual_sigs: expr) => {
2745 let htlc = HTLCOutputInCommitment {
2746 offered: if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::OfferedHTLC { true } else { false },
2748 cltv_expiry: 2 << 16,
2749 payment_hash: PaymentHash([1; 32]),
2750 transaction_output_index: Some($idx as u32),
2752 let redeem_script = if *$input_type == InputDescriptors::RevokedOutput { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &pubkey, &pubkey, &pubkey) };
2753 let sighash = hash_to_message!(&$sighash_parts.signature_hash($idx, &redeem_script, $amount, SigHashType::All)[..]);
2754 let sig = secp_ctx.sign(&sighash, &privkey);
2755 $sighash_parts.access_witness($idx).push(sig.serialize_der().to_vec());
2756 $sighash_parts.access_witness($idx)[0].push(SigHashType::All as u8);
2757 sum_actual_sigs += $sighash_parts.access_witness($idx)[0].len();
2758 if *$input_type == InputDescriptors::RevokedOutput {
2759 $sighash_parts.access_witness($idx).push(vec!(1));
2760 } else if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::RevokedReceivedHTLC {
2761 $sighash_parts.access_witness($idx).push(pubkey.clone().serialize().to_vec());
2762 } else if *$input_type == InputDescriptors::ReceivedHTLC {
2763 $sighash_parts.access_witness($idx).push(vec![0]);
2765 $sighash_parts.access_witness($idx).push(PaymentPreimage([1; 32]).0.to_vec());
2767 $sighash_parts.access_witness($idx).push(redeem_script.into_bytes());
2768 println!("witness[0] {}", $sighash_parts.access_witness($idx)[0].len());
2769 println!("witness[1] {}", $sighash_parts.access_witness($idx)[1].len());
2770 println!("witness[2] {}", $sighash_parts.access_witness($idx)[2].len());
2774 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
2775 let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
2777 // Justice tx with 1 to_holder, 2 revoked offered HTLCs, 1 revoked received HTLCs
2778 let mut claim_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2780 claim_tx.input.push(TxIn {
2781 previous_output: BitcoinOutPoint {
2785 script_sig: Script::new(),
2786 sequence: 0xfffffffd,
2787 witness: Vec::new(),
2790 claim_tx.output.push(TxOut {
2791 script_pubkey: script_pubkey.clone(),
2794 let base_weight = claim_tx.get_weight();
2795 let inputs_des = vec![InputDescriptors::RevokedOutput, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedReceivedHTLC];
2797 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
2798 for (idx, inp) in inputs_des.iter().enumerate() {
2799 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
2802 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));
2804 // Claim tx with 1 offered HTLCs, 3 received HTLCs
2805 claim_tx.input.clear();
2806 sum_actual_sigs = 0;
2808 claim_tx.input.push(TxIn {
2809 previous_output: BitcoinOutPoint {
2813 script_sig: Script::new(),
2814 sequence: 0xfffffffd,
2815 witness: Vec::new(),
2818 let base_weight = claim_tx.get_weight();
2819 let inputs_des = vec![InputDescriptors::OfferedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC];
2821 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
2822 for (idx, inp) in inputs_des.iter().enumerate() {
2823 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
2826 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));
2828 // Justice tx with 1 revoked HTLC-Success tx output
2829 claim_tx.input.clear();
2830 sum_actual_sigs = 0;
2831 claim_tx.input.push(TxIn {
2832 previous_output: BitcoinOutPoint {
2836 script_sig: Script::new(),
2837 sequence: 0xfffffffd,
2838 witness: Vec::new(),
2840 let base_weight = claim_tx.get_weight();
2841 let inputs_des = vec![InputDescriptors::RevokedOutput];
2843 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
2844 for (idx, inp) in inputs_des.iter().enumerate() {
2845 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
2848 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));
2851 // Further testing is done in the ChannelManager integration tests.