1 // This file is Copyright its original authors, visible in version control
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
7 // You may not use this file except in accordance with one or both of these
10 //! The logic to monitor for on-chain transactions and create the relevant claim responses lives
13 //! ChannelMonitor objects are generated by ChannelManager in response to relevant
14 //! messages/actions, and MUST be persisted to disk (and, preferably, remotely) before progress can
15 //! be made in responding to certain messages, see ManyChannelMonitor for more.
17 //! Note that ChannelMonitors are an important part of the lightning trust model and a copy of the
18 //! latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date
19 //! ChannelMonitors should do so). Thus, if you're building rust-lightning into an HSM or other
20 //! security-domain-separated system design, you should consider having multiple paths for
21 //! ChannelMonitors to get out of the HSM and onto monitoring devices.
23 use bitcoin::blockdata::block::BlockHeader;
24 use bitcoin::blockdata::transaction::{TxOut,Transaction};
25 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
26 use bitcoin::blockdata::script::{Script, Builder};
27 use bitcoin::blockdata::opcodes;
28 use bitcoin::consensus::encode;
29 use bitcoin::util::hash::BitcoinHash;
31 use bitcoin::hashes::Hash;
32 use bitcoin::hashes::sha256::Hash as Sha256;
33 use bitcoin::hash_types::{Txid, BlockHash, WPubkeyHash};
35 use bitcoin::secp256k1::{Secp256k1,Signature};
36 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
37 use bitcoin::secp256k1;
39 use ln::msgs::DecodeError;
41 use ln::chan_utils::{CounterpartyCommitmentSecrets, HTLCOutputInCommitment, LocalCommitmentTransaction, HTLCType};
42 use ln::channelmanager::{HTLCSource, PaymentPreimage, PaymentHash};
43 use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
44 use chain::chaininterface::{ChainListener, ChainWatchInterface, BroadcasterInterface, FeeEstimator};
45 use chain::transaction::OutPoint;
46 use chain::keysinterface::{SpendableOutputDescriptor, ChannelKeys};
47 use util::logger::Logger;
48 use util::ser::{Readable, MaybeReadable, Writer, Writeable, U48};
49 use util::{byte_utils, events};
50 use util::events::Event;
52 use std::collections::{HashMap, hash_map};
54 use std::{hash,cmp, mem};
58 /// An update generated by the underlying Channel itself which contains some new information the
59 /// ChannelMonitor should be made aware of.
60 #[cfg_attr(test, derive(PartialEq))]
63 pub struct ChannelMonitorUpdate {
64 pub(super) updates: Vec<ChannelMonitorUpdateStep>,
65 /// The sequence number of this update. Updates *must* be replayed in-order according to this
66 /// sequence number (and updates may panic if they are not). The update_id values are strictly
67 /// increasing and increase by one for each new update.
69 /// This sequence number is also used to track up to which points updates which returned
70 /// ChannelMonitorUpdateErr::TemporaryFailure have been applied to all copies of a given
71 /// ChannelMonitor when ChannelManager::channel_monitor_updated is called.
75 impl Writeable for ChannelMonitorUpdate {
76 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
77 self.update_id.write(w)?;
78 (self.updates.len() as u64).write(w)?;
79 for update_step in self.updates.iter() {
80 update_step.write(w)?;
85 impl Readable for ChannelMonitorUpdate {
86 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
87 let update_id: u64 = Readable::read(r)?;
88 let len: u64 = Readable::read(r)?;
89 let mut updates = Vec::with_capacity(cmp::min(len as usize, MAX_ALLOC_SIZE / ::std::mem::size_of::<ChannelMonitorUpdateStep>()));
91 updates.push(Readable::read(r)?);
93 Ok(Self { update_id, updates })
97 /// An error enum representing a failure to persist a channel monitor update.
99 pub enum ChannelMonitorUpdateErr {
100 /// Used to indicate a temporary failure (eg connection to a watchtower or remote backup of
101 /// our state failed, but is expected to succeed at some point in the future).
103 /// Such a failure will "freeze" a channel, preventing us from revoking old states or
104 /// submitting new commitment transactions to the remote party. Once the update(s) which failed
105 /// have been successfully applied, ChannelManager::channel_monitor_updated can be used to
106 /// restore the channel to an operational state.
108 /// Note that a given ChannelManager will *never* re-generate a given ChannelMonitorUpdate. If
109 /// you return a TemporaryFailure you must ensure that it is written to disk safely before
110 /// writing out the latest ChannelManager state.
112 /// Even when a channel has been "frozen" updates to the ChannelMonitor can continue to occur
113 /// (eg if an inbound HTLC which we forwarded was claimed upstream resulting in us attempting
114 /// to claim it on this channel) and those updates must be applied wherever they can be. At
115 /// least one such updated ChannelMonitor must be persisted otherwise PermanentFailure should
116 /// be returned to get things on-chain ASAP using only the in-memory copy. Obviously updates to
117 /// the channel which would invalidate previous ChannelMonitors are not made when a channel has
120 /// Note that even if updates made after TemporaryFailure succeed you must still call
121 /// channel_monitor_updated to ensure you have the latest monitor and re-enable normal channel
124 /// Note that the update being processed here will not be replayed for you when you call
125 /// ChannelManager::channel_monitor_updated, so you must store the update itself along
126 /// with the persisted ChannelMonitor on your own local disk prior to returning a
127 /// TemporaryFailure. You may, of course, employ a journaling approach, storing only the
128 /// ChannelMonitorUpdate on disk without updating the monitor itself, replaying the journal at
131 /// For deployments where a copy of ChannelMonitors and other local state are backed up in a
132 /// remote location (with local copies persisted immediately), it is anticipated that all
133 /// updates will return TemporaryFailure until the remote copies could be updated.
135 /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
136 /// different watchtower and cannot update with all watchtowers that were previously informed
137 /// of this channel). This will force-close the channel in question (which will generate one
138 /// final ChannelMonitorUpdate which must be delivered to at least one ChannelMonitor copy).
140 /// Should also be used to indicate a failure to update the local persisted copy of the channel
145 /// General Err type for ChannelMonitor actions. Generally, this implies that the data provided is
146 /// inconsistent with the ChannelMonitor being called. eg for ChannelMonitor::update_monitor this
147 /// means you tried to update a monitor for a different channel or the ChannelMonitorUpdate was
149 /// Contains a human-readable error message.
151 pub struct MonitorUpdateError(pub &'static str);
153 /// An event to be processed by the ChannelManager.
155 pub enum MonitorEvent {
156 /// A monitor event containing an HTLCUpdate.
157 HTLCEvent(HTLCUpdate),
159 /// A monitor event that the Channel's commitment transaction was broadcasted.
160 CommitmentTxBroadcasted(OutPoint),
163 /// Simple structure send back by ManyChannelMonitor in case of HTLC detected onchain from a
164 /// forward channel and from which info are needed to update HTLC in a backward channel.
165 #[derive(Clone, PartialEq)]
166 pub struct HTLCUpdate {
167 pub(super) payment_hash: PaymentHash,
168 pub(super) payment_preimage: Option<PaymentPreimage>,
169 pub(super) source: HTLCSource
171 impl_writeable!(HTLCUpdate, 0, { payment_hash, payment_preimage, source });
173 /// A simple implementation of a ManyChannelMonitor and ChainListener. Can be used to create a
174 /// watchtower or watch our own channels.
176 /// Note that you must provide your own key by which to refer to channels.
178 /// If you're accepting remote monitors (ie are implementing a watchtower), you must verify that
179 /// users cannot overwrite a given channel by providing a duplicate key. ie you should probably
180 /// index by a PublicKey which is required to sign any updates.
182 /// If you're using this for local monitoring of your own channels, you probably want to use
183 /// `OutPoint` as the key, which will give you a ManyChannelMonitor implementation.
184 pub struct SimpleManyChannelMonitor<Key, ChanSigner: ChannelKeys, T: Deref, F: Deref, L: Deref, C: Deref>
185 where T::Target: BroadcasterInterface,
186 F::Target: FeeEstimator,
188 C::Target: ChainWatchInterface,
191 pub monitors: Mutex<HashMap<Key, ChannelMonitor<ChanSigner>>>,
198 impl<Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys, T: Deref + Sync + Send, F: Deref + Sync + Send, L: Deref + Sync + Send, C: Deref + Sync + Send>
199 ChainListener for SimpleManyChannelMonitor<Key, ChanSigner, T, F, L, C>
200 where T::Target: BroadcasterInterface,
201 F::Target: FeeEstimator,
203 C::Target: ChainWatchInterface,
205 fn block_connected(&self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], _indexes_of_txn_matched: &[usize]) {
206 let block_hash = header.bitcoin_hash();
208 let mut monitors = self.monitors.lock().unwrap();
209 for monitor in monitors.values_mut() {
210 let txn_outputs = monitor.block_connected(txn_matched, height, &block_hash, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
212 for (ref txid, ref outputs) in txn_outputs {
213 for (idx, output) in outputs.iter().enumerate() {
214 self.chain_monitor.install_watch_outpoint((txid.clone(), idx as u32), &output.script_pubkey);
221 fn block_disconnected(&self, header: &BlockHeader, disconnected_height: u32) {
222 let block_hash = header.bitcoin_hash();
223 let mut monitors = self.monitors.lock().unwrap();
224 for monitor in monitors.values_mut() {
225 monitor.block_disconnected(disconnected_height, &block_hash, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
230 impl<Key : Send + cmp::Eq + hash::Hash + 'static, ChanSigner: ChannelKeys, T: Deref, F: Deref, L: Deref, C: Deref> SimpleManyChannelMonitor<Key, ChanSigner, T, F, L, C>
231 where T::Target: BroadcasterInterface,
232 F::Target: FeeEstimator,
234 C::Target: ChainWatchInterface,
236 /// Creates a new object which can be used to monitor several channels given the chain
237 /// interface with which to register to receive notifications.
238 pub fn new(chain_monitor: C, broadcaster: T, logger: L, feeest: F) -> SimpleManyChannelMonitor<Key, ChanSigner, T, F, L, C> {
239 let res = SimpleManyChannelMonitor {
240 monitors: Mutex::new(HashMap::new()),
244 fee_estimator: feeest,
250 /// Adds or updates the monitor which monitors the channel referred to by the given key.
251 pub fn add_monitor_by_key(&self, key: Key, monitor: ChannelMonitor<ChanSigner>) -> Result<(), MonitorUpdateError> {
252 let mut monitors = self.monitors.lock().unwrap();
253 let entry = match monitors.entry(key) {
254 hash_map::Entry::Occupied(_) => return Err(MonitorUpdateError("Channel monitor for given key is already present")),
255 hash_map::Entry::Vacant(e) => e,
258 let funding_txo = monitor.get_funding_txo();
259 log_trace!(self.logger, "Got new Channel Monitor for channel {}", log_bytes!(funding_txo.0.to_channel_id()[..]));
260 self.chain_monitor.install_watch_tx(&funding_txo.0.txid, &funding_txo.1);
261 self.chain_monitor.install_watch_outpoint((funding_txo.0.txid, funding_txo.0.index as u32), &funding_txo.1);
262 for (txid, outputs) in monitor.get_outputs_to_watch().iter() {
263 for (idx, script) in outputs.iter().enumerate() {
264 self.chain_monitor.install_watch_outpoint((*txid, idx as u32), script);
268 entry.insert(monitor);
272 /// Updates the monitor which monitors the channel referred to by the given key.
273 pub fn update_monitor_by_key(&self, key: Key, update: ChannelMonitorUpdate) -> Result<(), MonitorUpdateError> {
274 let mut monitors = self.monitors.lock().unwrap();
275 match monitors.get_mut(&key) {
276 Some(orig_monitor) => {
277 log_trace!(self.logger, "Updating Channel Monitor for channel {}", log_funding_info!(orig_monitor));
278 orig_monitor.update_monitor(update, &self.broadcaster, &self.logger)
280 None => Err(MonitorUpdateError("No such monitor registered"))
285 impl<ChanSigner: ChannelKeys, T: Deref + Sync + Send, F: Deref + Sync + Send, L: Deref + Sync + Send, C: Deref + Sync + Send> ManyChannelMonitor for SimpleManyChannelMonitor<OutPoint, ChanSigner, T, F, L, C>
286 where T::Target: BroadcasterInterface,
287 F::Target: FeeEstimator,
289 C::Target: ChainWatchInterface,
291 type Keys = ChanSigner;
293 fn add_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor<ChanSigner>) -> Result<(), ChannelMonitorUpdateErr> {
294 match self.add_monitor_by_key(funding_txo, monitor) {
296 Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
300 fn update_monitor(&self, funding_txo: OutPoint, update: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr> {
301 match self.update_monitor_by_key(funding_txo, update) {
303 Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
307 fn get_and_clear_pending_monitor_events(&self) -> Vec<MonitorEvent> {
308 let mut pending_monitor_events = Vec::new();
309 for chan in self.monitors.lock().unwrap().values_mut() {
310 pending_monitor_events.append(&mut chan.get_and_clear_pending_monitor_events());
312 pending_monitor_events
316 impl<Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys, T: Deref, F: Deref, L: Deref, C: Deref> events::EventsProvider for SimpleManyChannelMonitor<Key, ChanSigner, T, F, L, C>
317 where T::Target: BroadcasterInterface,
318 F::Target: FeeEstimator,
320 C::Target: ChainWatchInterface,
322 fn get_and_clear_pending_events(&self) -> Vec<Event> {
323 let mut pending_events = Vec::new();
324 for chan in self.monitors.lock().unwrap().values_mut() {
325 pending_events.append(&mut chan.get_and_clear_pending_events());
331 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
332 /// instead claiming it in its own individual transaction.
333 pub(crate) const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
334 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
335 /// HTLC-Success transaction.
336 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
337 /// transaction confirmed (and we use it in a few more, equivalent, places).
338 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 6;
339 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
340 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
341 /// copies of ChannelMonitors, including watchtowers). We could enforce the contract by failing
342 /// at CLTV expiration height but giving a grace period to our peer may be profitable for us if he
343 /// can provide an over-late preimage. Nevertheless, grace period has to be accounted in our
344 /// CLTV_EXPIRY_DELTA to be secure. Following this policy we may decrease the rate of channel failures
345 /// due to expiration but increase the cost of funds being locked longuer in case of failure.
346 /// This delay also cover a low-power peer being slow to process blocks and so being behind us on
347 /// accurate block height.
348 /// In case of onchain failure to be pass backward we may see the last block of ANTI_REORG_DELAY
349 /// with at worst this delay, so we are not only using this value as a mercy for them but also
350 /// us as a safeguard to delay with enough time.
351 pub(crate) const LATENCY_GRACE_PERIOD_BLOCKS: u32 = 3;
352 /// Number of blocks we wait on seeing a HTLC output being solved before we fail corresponding inbound
353 /// HTLCs. This prevents us from failing backwards and then getting a reorg resulting in us losing money.
354 /// We use also this delay to be sure we can remove our in-flight claim txn from bump candidates buffer.
355 /// It may cause spurrious generation of bumped claim txn but that's allright given the outpoint is already
356 /// solved by a previous claim tx. What we want to avoid is reorg evicting our claim tx and us not
357 /// keeping bumping another claim tx to solve the outpoint.
358 pub(crate) const ANTI_REORG_DELAY: u32 = 6;
359 /// Number of blocks before confirmation at which we fail back an un-relayed HTLC or at which we
360 /// refuse to accept a new HTLC.
362 /// This is used for a few separate purposes:
363 /// 1) if we've received an MPP HTLC to us and it expires within this many blocks and we are
364 /// waiting on additional parts (or waiting on the preimage for any HTLC from the user), we will
366 /// 2) if we receive an HTLC within this many blocks of its expiry (plus one to avoid a race
367 /// condition with the above), we will fail this HTLC without telling the user we received it,
368 /// 3) if we are waiting on a connection or a channel state update to send an HTLC to a peer, and
369 /// that HTLC expires within this many blocks, we will simply fail the HTLC instead.
371 /// (1) is all about protecting us - we need enough time to update the channel state before we hit
372 /// CLTV_CLAIM_BUFFER, at which point we'd go on chain to claim the HTLC with the preimage.
374 /// (2) is the same, but with an additional buffer to avoid accepting an HTLC which is immediately
375 /// in a race condition between the user connecting a block (which would fail it) and the user
376 /// providing us the preimage (which would claim it).
378 /// (3) is about our counterparty - we don't want to relay an HTLC to a counterparty when they may
379 /// end up force-closing the channel on us to claim it.
380 pub(crate) const HTLC_FAIL_BACK_BUFFER: u32 = CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS;
382 #[derive(Clone, PartialEq)]
383 struct LocalSignedTx {
384 /// txid of the transaction in tx, just used to make comparison faster
386 revocation_key: PublicKey,
387 a_htlc_key: PublicKey,
388 b_htlc_key: PublicKey,
389 delayed_payment_key: PublicKey,
390 per_commitment_point: PublicKey,
392 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
395 /// We use this to track remote commitment transactions and htlcs outputs and
396 /// use it to generate any justice or 2nd-stage preimage/timeout transactions.
398 struct RemoteCommitmentTransaction {
399 remote_delayed_payment_base_key: PublicKey,
400 remote_htlc_base_key: PublicKey,
401 on_remote_tx_csv: u16,
402 per_htlc: HashMap<Txid, Vec<HTLCOutputInCommitment>>
405 impl Writeable for RemoteCommitmentTransaction {
406 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
407 self.remote_delayed_payment_base_key.write(w)?;
408 self.remote_htlc_base_key.write(w)?;
409 w.write_all(&byte_utils::be16_to_array(self.on_remote_tx_csv))?;
410 w.write_all(&byte_utils::be64_to_array(self.per_htlc.len() as u64))?;
411 for (ref txid, ref htlcs) in self.per_htlc.iter() {
412 w.write_all(&txid[..])?;
413 w.write_all(&byte_utils::be64_to_array(htlcs.len() as u64))?;
414 for &ref htlc in htlcs.iter() {
421 impl Readable for RemoteCommitmentTransaction {
422 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
423 let remote_commitment_transaction = {
424 let remote_delayed_payment_base_key = Readable::read(r)?;
425 let remote_htlc_base_key = Readable::read(r)?;
426 let on_remote_tx_csv: u16 = Readable::read(r)?;
427 let per_htlc_len: u64 = Readable::read(r)?;
428 let mut per_htlc = HashMap::with_capacity(cmp::min(per_htlc_len as usize, MAX_ALLOC_SIZE / 64));
429 for _ in 0..per_htlc_len {
430 let txid: Txid = Readable::read(r)?;
431 let htlcs_count: u64 = Readable::read(r)?;
432 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
433 for _ in 0..htlcs_count {
434 let htlc = Readable::read(r)?;
437 if let Some(_) = per_htlc.insert(txid, htlcs) {
438 return Err(DecodeError::InvalidValue);
441 RemoteCommitmentTransaction {
442 remote_delayed_payment_base_key,
443 remote_htlc_base_key,
448 Ok(remote_commitment_transaction)
452 /// When ChannelMonitor discovers an onchain outpoint being a step of a channel and that it needs
453 /// to generate a tx to push channel state forward, we cache outpoint-solving tx material to build
454 /// a new bumped one in case of lenghty confirmation delay
455 #[derive(Clone, PartialEq)]
456 pub(crate) enum InputMaterial {
458 per_commitment_point: PublicKey,
459 remote_delayed_payment_base_key: PublicKey,
460 remote_htlc_base_key: PublicKey,
461 per_commitment_key: SecretKey,
462 input_descriptor: InputDescriptors,
464 htlc: Option<HTLCOutputInCommitment>,
465 on_remote_tx_csv: u16,
468 per_commitment_point: PublicKey,
469 remote_delayed_payment_base_key: PublicKey,
470 remote_htlc_base_key: PublicKey,
471 preimage: Option<PaymentPreimage>,
472 htlc: HTLCOutputInCommitment
475 preimage: Option<PaymentPreimage>,
479 funding_redeemscript: Script,
483 impl Writeable for InputMaterial {
484 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
486 &InputMaterial::Revoked { ref per_commitment_point, ref remote_delayed_payment_base_key, ref remote_htlc_base_key, ref per_commitment_key, ref input_descriptor, ref amount, ref htlc, ref on_remote_tx_csv} => {
487 writer.write_all(&[0; 1])?;
488 per_commitment_point.write(writer)?;
489 remote_delayed_payment_base_key.write(writer)?;
490 remote_htlc_base_key.write(writer)?;
491 writer.write_all(&per_commitment_key[..])?;
492 input_descriptor.write(writer)?;
493 writer.write_all(&byte_utils::be64_to_array(*amount))?;
495 on_remote_tx_csv.write(writer)?;
497 &InputMaterial::RemoteHTLC { ref per_commitment_point, ref remote_delayed_payment_base_key, ref remote_htlc_base_key, ref preimage, ref htlc} => {
498 writer.write_all(&[1; 1])?;
499 per_commitment_point.write(writer)?;
500 remote_delayed_payment_base_key.write(writer)?;
501 remote_htlc_base_key.write(writer)?;
502 preimage.write(writer)?;
505 &InputMaterial::LocalHTLC { ref preimage, ref amount } => {
506 writer.write_all(&[2; 1])?;
507 preimage.write(writer)?;
508 writer.write_all(&byte_utils::be64_to_array(*amount))?;
510 &InputMaterial::Funding { ref funding_redeemscript } => {
511 writer.write_all(&[3; 1])?;
512 funding_redeemscript.write(writer)?;
519 impl Readable for InputMaterial {
520 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
521 let input_material = match <u8 as Readable>::read(reader)? {
523 let per_commitment_point = Readable::read(reader)?;
524 let remote_delayed_payment_base_key = Readable::read(reader)?;
525 let remote_htlc_base_key = Readable::read(reader)?;
526 let per_commitment_key = Readable::read(reader)?;
527 let input_descriptor = Readable::read(reader)?;
528 let amount = Readable::read(reader)?;
529 let htlc = Readable::read(reader)?;
530 let on_remote_tx_csv = Readable::read(reader)?;
531 InputMaterial::Revoked {
532 per_commitment_point,
533 remote_delayed_payment_base_key,
534 remote_htlc_base_key,
543 let per_commitment_point = Readable::read(reader)?;
544 let remote_delayed_payment_base_key = Readable::read(reader)?;
545 let remote_htlc_base_key = Readable::read(reader)?;
546 let preimage = Readable::read(reader)?;
547 let htlc = Readable::read(reader)?;
548 InputMaterial::RemoteHTLC {
549 per_commitment_point,
550 remote_delayed_payment_base_key,
551 remote_htlc_base_key,
557 let preimage = Readable::read(reader)?;
558 let amount = Readable::read(reader)?;
559 InputMaterial::LocalHTLC {
565 InputMaterial::Funding {
566 funding_redeemscript: Readable::read(reader)?,
569 _ => return Err(DecodeError::InvalidValue),
575 /// ClaimRequest is a descriptor structure to communicate between detection
576 /// and reaction module. They are generated by ChannelMonitor while parsing
577 /// onchain txn leaked from a channel and handed over to OnchainTxHandler which
578 /// is responsible for opportunistic aggregation, selecting and enforcing
579 /// bumping logic, building and signing transactions.
580 pub(crate) struct ClaimRequest {
581 // Block height before which claiming is exclusive to one party,
582 // after reaching it, claiming may be contentious.
583 pub(crate) absolute_timelock: u32,
584 // Timeout tx must have nLocktime set which means aggregating multiple
585 // ones must take the higher nLocktime among them to satisfy all of them.
586 // Sadly it has few pitfalls, a) it takes longuer to get fund back b) CLTV_DELTA
587 // of a sooner-HTLC could be swallowed by the highest nLocktime of the HTLC set.
588 // Do simplify we mark them as non-aggregable.
589 pub(crate) aggregable: bool,
590 // Basic bitcoin outpoint (txid, vout)
591 pub(crate) outpoint: BitcoinOutPoint,
592 // Following outpoint type, set of data needed to generate transaction digest
593 // and satisfy witness program.
594 pub(crate) witness_data: InputMaterial
597 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
598 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
599 #[derive(Clone, PartialEq)]
601 /// HTLC output getting solved by a timeout, at maturation we pass upstream payment source information to solve
602 /// inbound HTLC in backward channel. Note, in case of preimage, we pass info to upstream without delay as we can
603 /// only win from it, so it's never an OnchainEvent
605 htlc_update: (HTLCSource, PaymentHash),
608 descriptor: SpendableOutputDescriptor,
612 const SERIALIZATION_VERSION: u8 = 1;
613 const MIN_SERIALIZATION_VERSION: u8 = 1;
615 #[cfg_attr(test, derive(PartialEq))]
617 pub(super) enum ChannelMonitorUpdateStep {
618 LatestLocalCommitmentTXInfo {
619 commitment_tx: LocalCommitmentTransaction,
620 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
622 LatestRemoteCommitmentTXInfo {
623 unsigned_commitment_tx: Transaction, // TODO: We should actually only need the txid here
624 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
625 commitment_number: u64,
626 their_revocation_point: PublicKey,
629 payment_preimage: PaymentPreimage,
635 /// Used to indicate that the no future updates will occur, and likely that the latest local
636 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
638 /// If set to false, we shouldn't broadcast the latest local commitment transaction as we
639 /// think we've fallen behind!
640 should_broadcast: bool,
644 impl Writeable for ChannelMonitorUpdateStep {
645 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
647 &ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { ref commitment_tx, ref htlc_outputs } => {
649 commitment_tx.write(w)?;
650 (htlc_outputs.len() as u64).write(w)?;
651 for &(ref output, ref signature, ref source) in htlc_outputs.iter() {
657 &ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { ref unsigned_commitment_tx, ref htlc_outputs, ref commitment_number, ref their_revocation_point } => {
659 unsigned_commitment_tx.write(w)?;
660 commitment_number.write(w)?;
661 their_revocation_point.write(w)?;
662 (htlc_outputs.len() as u64).write(w)?;
663 for &(ref output, ref source) in htlc_outputs.iter() {
665 source.as_ref().map(|b| b.as_ref()).write(w)?;
668 &ChannelMonitorUpdateStep::PaymentPreimage { ref payment_preimage } => {
670 payment_preimage.write(w)?;
672 &ChannelMonitorUpdateStep::CommitmentSecret { ref idx, ref secret } => {
677 &ChannelMonitorUpdateStep::ChannelForceClosed { ref should_broadcast } => {
679 should_broadcast.write(w)?;
685 impl Readable for ChannelMonitorUpdateStep {
686 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
687 match Readable::read(r)? {
689 Ok(ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo {
690 commitment_tx: Readable::read(r)?,
692 let len: u64 = Readable::read(r)?;
693 let mut res = Vec::new();
695 res.push((Readable::read(r)?, Readable::read(r)?, Readable::read(r)?));
702 Ok(ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo {
703 unsigned_commitment_tx: Readable::read(r)?,
704 commitment_number: Readable::read(r)?,
705 their_revocation_point: Readable::read(r)?,
707 let len: u64 = Readable::read(r)?;
708 let mut res = Vec::new();
710 res.push((Readable::read(r)?, <Option<HTLCSource> as Readable>::read(r)?.map(|o| Box::new(o))));
717 Ok(ChannelMonitorUpdateStep::PaymentPreimage {
718 payment_preimage: Readable::read(r)?,
722 Ok(ChannelMonitorUpdateStep::CommitmentSecret {
723 idx: Readable::read(r)?,
724 secret: Readable::read(r)?,
728 Ok(ChannelMonitorUpdateStep::ChannelForceClosed {
729 should_broadcast: Readable::read(r)?
732 _ => Err(DecodeError::InvalidValue),
737 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
738 /// on-chain transactions to ensure no loss of funds occurs.
740 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
741 /// information and are actively monitoring the chain.
743 /// Pending Events or updated HTLCs which have not yet been read out by
744 /// get_and_clear_pending_monitor_events or get_and_clear_pending_events are serialized to disk and
745 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
746 /// gotten are fully handled before re-serializing the new state.
747 pub struct ChannelMonitor<ChanSigner: ChannelKeys> {
748 latest_update_id: u64,
749 commitment_transaction_number_obscure_factor: u64,
751 destination_script: Script,
752 broadcasted_local_revokable_script: Option<(Script, PublicKey, PublicKey)>,
753 remote_payment_script: Script,
754 shutdown_script: Script,
757 funding_info: (OutPoint, Script),
758 current_remote_commitment_txid: Option<Txid>,
759 prev_remote_commitment_txid: Option<Txid>,
761 remote_tx_cache: RemoteCommitmentTransaction,
762 funding_redeemscript: Script,
763 channel_value_satoshis: u64,
764 // first is the idx of the first of the two revocation points
765 their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
767 on_local_tx_csv: u16,
769 commitment_secrets: CounterpartyCommitmentSecrets,
770 remote_claimable_outpoints: HashMap<Txid, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
771 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
772 /// Nor can we figure out their commitment numbers without the commitment transaction they are
773 /// spending. Thus, in order to claim them via revocation key, we track all the remote
774 /// commitment transactions which we find on-chain, mapping them to the commitment number which
775 /// can be used to derive the revocation key and claim the transactions.
776 remote_commitment_txn_on_chain: HashMap<Txid, (u64, Vec<Script>)>,
777 /// Cache used to make pruning of payment_preimages faster.
778 /// Maps payment_hash values to commitment numbers for remote transactions for non-revoked
779 /// remote transactions (ie should remain pretty small).
780 /// Serialized to disk but should generally not be sent to Watchtowers.
781 remote_hash_commitment_number: HashMap<PaymentHash, u64>,
783 // We store two local commitment transactions to avoid any race conditions where we may update
784 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
785 // various monitors for one channel being out of sync, and us broadcasting a local
786 // transaction for which we have deleted claim information on some watchtowers.
787 prev_local_signed_commitment_tx: Option<LocalSignedTx>,
788 current_local_commitment_tx: LocalSignedTx,
790 // Used just for ChannelManager to make sure it has the latest channel data during
792 current_remote_commitment_number: u64,
793 // Used just for ChannelManager to make sure it has the latest channel data during
795 current_local_commitment_number: u64,
797 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
799 pending_monitor_events: Vec<MonitorEvent>,
800 pending_events: Vec<Event>,
802 // Used to track onchain events, i.e transactions parts of channels confirmed on chain, on which
803 // we have to take actions once they reach enough confs. Key is a block height timer, i.e we enforce
804 // actions when we receive a block with given height. Actions depend on OnchainEvent type.
805 onchain_events_waiting_threshold_conf: HashMap<u32, Vec<OnchainEvent>>,
807 // If we get serialized out and re-read, we need to make sure that the chain monitoring
808 // interface knows about the TXOs that we want to be notified of spends of. We could probably
809 // be smart and derive them from the above storage fields, but its much simpler and more
810 // Obviously Correct (tm) if we just keep track of them explicitly.
811 outputs_to_watch: HashMap<Txid, Vec<Script>>,
814 pub onchain_tx_handler: OnchainTxHandler<ChanSigner>,
816 onchain_tx_handler: OnchainTxHandler<ChanSigner>,
818 // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
819 // channel has been force-closed. After this is set, no further local commitment transaction
820 // updates may occur, and we panic!() if one is provided.
821 lockdown_from_offchain: bool,
823 // Set once we've signed a local commitment transaction and handed it over to our
824 // OnchainTxHandler. After this is set, no future updates to our local commitment transactions
825 // may occur, and we fail any such monitor updates.
826 local_tx_signed: bool,
828 // We simply modify last_block_hash in Channel's block_connected so that serialization is
829 // consistent but hopefully the users' copy handles block_connected in a consistent way.
830 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
831 // their last_block_hash from its state and not based on updated copies that didn't run through
832 // the full block_connected).
833 last_block_hash: BlockHash,
834 secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
837 /// Simple trait indicating ability to track a set of ChannelMonitors and multiplex events between
838 /// them. Generally should be implemented by keeping a local SimpleManyChannelMonitor and passing
839 /// events to it, while also taking any add/update_monitor events and passing them to some remote
842 /// In general, you must always have at least one local copy in memory, which must never fail to
843 /// update (as it is responsible for broadcasting the latest state in case the channel is closed),
844 /// and then persist it to various on-disk locations. If, for some reason, the in-memory copy fails
845 /// to update (eg out-of-memory or some other condition), you must immediately shut down without
846 /// taking any further action such as writing the current state to disk. This should likely be
847 /// accomplished via panic!() or abort().
849 /// Note that any updates to a channel's monitor *must* be applied to each instance of the
850 /// channel's monitor everywhere (including remote watchtowers) *before* this function returns. If
851 /// an update occurs and a remote watchtower is left with old state, it may broadcast transactions
852 /// which we have revoked, allowing our counterparty to claim all funds in the channel!
854 /// User needs to notify implementors of ManyChannelMonitor when a new block is connected or
855 /// disconnected using their `block_connected` and `block_disconnected` methods. However, rather
856 /// than calling these methods directly, the user should register implementors as listeners to the
857 /// BlockNotifier and call the BlockNotifier's `block_(dis)connected` methods, which will notify
858 /// all registered listeners in one go.
859 pub trait ManyChannelMonitor: Send + Sync {
860 /// The concrete type which signs for transactions and provides access to our channel public
862 type Keys: ChannelKeys;
864 /// Adds a monitor for the given `funding_txo`.
866 /// Implementer must also ensure that the funding_txo txid *and* outpoint are registered with
867 /// any relevant ChainWatchInterfaces such that the provided monitor receives block_connected
868 /// callbacks with the funding transaction, or any spends of it.
870 /// Further, the implementer must also ensure that each output returned in
871 /// monitor.get_outputs_to_watch() is registered to ensure that the provided monitor learns about
872 /// any spends of any of the outputs.
874 /// Any spends of outputs which should have been registered which aren't passed to
875 /// ChannelMonitors via block_connected may result in FUNDS LOSS.
876 fn add_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor<Self::Keys>) -> Result<(), ChannelMonitorUpdateErr>;
878 /// Updates a monitor for the given `funding_txo`.
880 /// Implementer must also ensure that the funding_txo txid *and* outpoint are registered with
881 /// any relevant ChainWatchInterfaces such that the provided monitor receives block_connected
882 /// callbacks with the funding transaction, or any spends of it.
884 /// Further, the implementer must also ensure that each output returned in
885 /// monitor.get_watch_outputs() is registered to ensure that the provided monitor learns about
886 /// any spends of any of the outputs.
888 /// Any spends of outputs which should have been registered which aren't passed to
889 /// ChannelMonitors via block_connected may result in FUNDS LOSS.
890 fn update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr>;
892 /// Used by ChannelManager to get list of HTLC resolved onchain and which needed to be updated
893 /// with success or failure.
895 /// You should probably just call through to
896 /// ChannelMonitor::get_and_clear_pending_monitor_events() for each ChannelMonitor and return
898 fn get_and_clear_pending_monitor_events(&self) -> Vec<MonitorEvent>;
901 #[cfg(any(test, feature = "fuzztarget"))]
902 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
903 /// underlying object
904 impl<ChanSigner: ChannelKeys> PartialEq for ChannelMonitor<ChanSigner> {
905 fn eq(&self, other: &Self) -> bool {
906 if self.latest_update_id != other.latest_update_id ||
907 self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
908 self.destination_script != other.destination_script ||
909 self.broadcasted_local_revokable_script != other.broadcasted_local_revokable_script ||
910 self.remote_payment_script != other.remote_payment_script ||
911 self.keys.pubkeys() != other.keys.pubkeys() ||
912 self.funding_info != other.funding_info ||
913 self.current_remote_commitment_txid != other.current_remote_commitment_txid ||
914 self.prev_remote_commitment_txid != other.prev_remote_commitment_txid ||
915 self.remote_tx_cache != other.remote_tx_cache ||
916 self.funding_redeemscript != other.funding_redeemscript ||
917 self.channel_value_satoshis != other.channel_value_satoshis ||
918 self.their_cur_revocation_points != other.their_cur_revocation_points ||
919 self.on_local_tx_csv != other.on_local_tx_csv ||
920 self.commitment_secrets != other.commitment_secrets ||
921 self.remote_claimable_outpoints != other.remote_claimable_outpoints ||
922 self.remote_commitment_txn_on_chain != other.remote_commitment_txn_on_chain ||
923 self.remote_hash_commitment_number != other.remote_hash_commitment_number ||
924 self.prev_local_signed_commitment_tx != other.prev_local_signed_commitment_tx ||
925 self.current_remote_commitment_number != other.current_remote_commitment_number ||
926 self.current_local_commitment_number != other.current_local_commitment_number ||
927 self.current_local_commitment_tx != other.current_local_commitment_tx ||
928 self.payment_preimages != other.payment_preimages ||
929 self.pending_monitor_events != other.pending_monitor_events ||
930 self.pending_events.len() != other.pending_events.len() || // We trust events to round-trip properly
931 self.onchain_events_waiting_threshold_conf != other.onchain_events_waiting_threshold_conf ||
932 self.outputs_to_watch != other.outputs_to_watch ||
933 self.lockdown_from_offchain != other.lockdown_from_offchain ||
934 self.local_tx_signed != other.local_tx_signed
943 impl<ChanSigner: ChannelKeys + Writeable> ChannelMonitor<ChanSigner> {
944 /// Writes this monitor into the given writer, suitable for writing to disk.
946 /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
947 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
948 /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
949 /// returned block hash and the the current chain and then reconnecting blocks to get to the
950 /// best chain) upon deserializing the object!
951 pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
952 //TODO: We still write out all the serialization here manually instead of using the fancy
953 //serialization framework we have, we should migrate things over to it.
954 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
955 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
957 self.latest_update_id.write(writer)?;
959 // Set in initial Channel-object creation, so should always be set by now:
960 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
962 self.destination_script.write(writer)?;
963 if let Some(ref broadcasted_local_revokable_script) = self.broadcasted_local_revokable_script {
964 writer.write_all(&[0; 1])?;
965 broadcasted_local_revokable_script.0.write(writer)?;
966 broadcasted_local_revokable_script.1.write(writer)?;
967 broadcasted_local_revokable_script.2.write(writer)?;
969 writer.write_all(&[1; 1])?;
972 self.remote_payment_script.write(writer)?;
973 self.shutdown_script.write(writer)?;
975 self.keys.write(writer)?;
976 writer.write_all(&self.funding_info.0.txid[..])?;
977 writer.write_all(&byte_utils::be16_to_array(self.funding_info.0.index))?;
978 self.funding_info.1.write(writer)?;
979 self.current_remote_commitment_txid.write(writer)?;
980 self.prev_remote_commitment_txid.write(writer)?;
982 self.remote_tx_cache.write(writer)?;
983 self.funding_redeemscript.write(writer)?;
984 self.channel_value_satoshis.write(writer)?;
986 match self.their_cur_revocation_points {
987 Some((idx, pubkey, second_option)) => {
988 writer.write_all(&byte_utils::be48_to_array(idx))?;
989 writer.write_all(&pubkey.serialize())?;
990 match second_option {
991 Some(second_pubkey) => {
992 writer.write_all(&second_pubkey.serialize())?;
995 writer.write_all(&[0; 33])?;
1000 writer.write_all(&byte_utils::be48_to_array(0))?;
1004 writer.write_all(&byte_utils::be16_to_array(self.on_local_tx_csv))?;
1006 self.commitment_secrets.write(writer)?;
1008 macro_rules! serialize_htlc_in_commitment {
1009 ($htlc_output: expr) => {
1010 writer.write_all(&[$htlc_output.offered as u8; 1])?;
1011 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
1012 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
1013 writer.write_all(&$htlc_output.payment_hash.0[..])?;
1014 $htlc_output.transaction_output_index.write(writer)?;
1018 writer.write_all(&byte_utils::be64_to_array(self.remote_claimable_outpoints.len() as u64))?;
1019 for (ref txid, ref htlc_infos) in self.remote_claimable_outpoints.iter() {
1020 writer.write_all(&txid[..])?;
1021 writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
1022 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
1023 serialize_htlc_in_commitment!(htlc_output);
1024 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
1028 writer.write_all(&byte_utils::be64_to_array(self.remote_commitment_txn_on_chain.len() as u64))?;
1029 for (ref txid, &(commitment_number, ref txouts)) in self.remote_commitment_txn_on_chain.iter() {
1030 writer.write_all(&txid[..])?;
1031 writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
1032 (txouts.len() as u64).write(writer)?;
1033 for script in txouts.iter() {
1034 script.write(writer)?;
1038 writer.write_all(&byte_utils::be64_to_array(self.remote_hash_commitment_number.len() as u64))?;
1039 for (ref payment_hash, commitment_number) in self.remote_hash_commitment_number.iter() {
1040 writer.write_all(&payment_hash.0[..])?;
1041 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
1044 macro_rules! serialize_local_tx {
1045 ($local_tx: expr) => {
1046 $local_tx.txid.write(writer)?;
1047 writer.write_all(&$local_tx.revocation_key.serialize())?;
1048 writer.write_all(&$local_tx.a_htlc_key.serialize())?;
1049 writer.write_all(&$local_tx.b_htlc_key.serialize())?;
1050 writer.write_all(&$local_tx.delayed_payment_key.serialize())?;
1051 writer.write_all(&$local_tx.per_commitment_point.serialize())?;
1053 writer.write_all(&byte_utils::be32_to_array($local_tx.feerate_per_kw))?;
1054 writer.write_all(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64))?;
1055 for &(ref htlc_output, ref sig, ref htlc_source) in $local_tx.htlc_outputs.iter() {
1056 serialize_htlc_in_commitment!(htlc_output);
1057 if let &Some(ref their_sig) = sig {
1059 writer.write_all(&their_sig.serialize_compact())?;
1063 htlc_source.write(writer)?;
1068 if let Some(ref prev_local_tx) = self.prev_local_signed_commitment_tx {
1069 writer.write_all(&[1; 1])?;
1070 serialize_local_tx!(prev_local_tx);
1072 writer.write_all(&[0; 1])?;
1075 serialize_local_tx!(self.current_local_commitment_tx);
1077 writer.write_all(&byte_utils::be48_to_array(self.current_remote_commitment_number))?;
1078 writer.write_all(&byte_utils::be48_to_array(self.current_local_commitment_number))?;
1080 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
1081 for payment_preimage in self.payment_preimages.values() {
1082 writer.write_all(&payment_preimage.0[..])?;
1085 writer.write_all(&byte_utils::be64_to_array(self.pending_monitor_events.len() as u64))?;
1086 for event in self.pending_monitor_events.iter() {
1088 MonitorEvent::HTLCEvent(upd) => {
1092 MonitorEvent::CommitmentTxBroadcasted(_) => 1u8.write(writer)?
1096 writer.write_all(&byte_utils::be64_to_array(self.pending_events.len() as u64))?;
1097 for event in self.pending_events.iter() {
1098 event.write(writer)?;
1101 self.last_block_hash.write(writer)?;
1103 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_waiting_threshold_conf.len() as u64))?;
1104 for (ref target, ref events) in self.onchain_events_waiting_threshold_conf.iter() {
1105 writer.write_all(&byte_utils::be32_to_array(**target))?;
1106 writer.write_all(&byte_utils::be64_to_array(events.len() as u64))?;
1107 for ev in events.iter() {
1109 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1111 htlc_update.0.write(writer)?;
1112 htlc_update.1.write(writer)?;
1114 OnchainEvent::MaturingOutput { ref descriptor } => {
1116 descriptor.write(writer)?;
1122 (self.outputs_to_watch.len() as u64).write(writer)?;
1123 for (txid, output_scripts) in self.outputs_to_watch.iter() {
1124 txid.write(writer)?;
1125 (output_scripts.len() as u64).write(writer)?;
1126 for script in output_scripts.iter() {
1127 script.write(writer)?;
1130 self.onchain_tx_handler.write(writer)?;
1132 self.lockdown_from_offchain.write(writer)?;
1133 self.local_tx_signed.write(writer)?;
1139 impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
1140 pub(super) fn new(keys: ChanSigner, shutdown_pubkey: &PublicKey,
1141 on_remote_tx_csv: u16, destination_script: &Script, funding_info: (OutPoint, Script),
1142 remote_htlc_base_key: &PublicKey, remote_delayed_payment_base_key: &PublicKey,
1143 on_local_tx_csv: u16, funding_redeemscript: Script, channel_value_satoshis: u64,
1144 commitment_transaction_number_obscure_factor: u64,
1145 initial_local_commitment_tx: LocalCommitmentTransaction) -> ChannelMonitor<ChanSigner> {
1147 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
1148 let our_channel_close_key_hash = WPubkeyHash::hash(&shutdown_pubkey.serialize());
1149 let shutdown_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
1150 let payment_key_hash = WPubkeyHash::hash(&keys.pubkeys().payment_point.serialize());
1151 let remote_payment_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_key_hash[..]).into_script();
1153 let remote_tx_cache = RemoteCommitmentTransaction { remote_delayed_payment_base_key: *remote_delayed_payment_base_key, remote_htlc_base_key: *remote_htlc_base_key, on_remote_tx_csv, per_htlc: HashMap::new() };
1155 let mut onchain_tx_handler = OnchainTxHandler::new(destination_script.clone(), keys.clone(), on_local_tx_csv);
1157 let local_tx_sequence = initial_local_commitment_tx.unsigned_tx.input[0].sequence as u64;
1158 let local_tx_locktime = initial_local_commitment_tx.unsigned_tx.lock_time as u64;
1159 let local_commitment_tx = LocalSignedTx {
1160 txid: initial_local_commitment_tx.txid(),
1161 revocation_key: initial_local_commitment_tx.local_keys.revocation_key,
1162 a_htlc_key: initial_local_commitment_tx.local_keys.a_htlc_key,
1163 b_htlc_key: initial_local_commitment_tx.local_keys.b_htlc_key,
1164 delayed_payment_key: initial_local_commitment_tx.local_keys.a_delayed_payment_key,
1165 per_commitment_point: initial_local_commitment_tx.local_keys.per_commitment_point,
1166 feerate_per_kw: initial_local_commitment_tx.feerate_per_kw,
1167 htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
1169 // Returning a monitor error before updating tracking points means in case of using
1170 // a concurrent watchtower implementation for same channel, if this one doesn't
1171 // reject update as we do, you MAY have the latest local valid commitment tx onchain
1172 // for which you want to spend outputs. We're NOT robust again this scenario right
1173 // now but we should consider it later.
1174 onchain_tx_handler.provide_latest_local_tx(initial_local_commitment_tx).unwrap();
1177 latest_update_id: 0,
1178 commitment_transaction_number_obscure_factor,
1180 destination_script: destination_script.clone(),
1181 broadcasted_local_revokable_script: None,
1182 remote_payment_script,
1187 current_remote_commitment_txid: None,
1188 prev_remote_commitment_txid: None,
1191 funding_redeemscript,
1192 channel_value_satoshis: channel_value_satoshis,
1193 their_cur_revocation_points: None,
1197 commitment_secrets: CounterpartyCommitmentSecrets::new(),
1198 remote_claimable_outpoints: HashMap::new(),
1199 remote_commitment_txn_on_chain: HashMap::new(),
1200 remote_hash_commitment_number: HashMap::new(),
1202 prev_local_signed_commitment_tx: None,
1203 current_local_commitment_tx: local_commitment_tx,
1204 current_remote_commitment_number: 1 << 48,
1205 current_local_commitment_number: 0xffff_ffff_ffff - ((((local_tx_sequence & 0xffffff) << 3*8) | (local_tx_locktime as u64 & 0xffffff)) ^ commitment_transaction_number_obscure_factor),
1207 payment_preimages: HashMap::new(),
1208 pending_monitor_events: Vec::new(),
1209 pending_events: Vec::new(),
1211 onchain_events_waiting_threshold_conf: HashMap::new(),
1212 outputs_to_watch: HashMap::new(),
1216 lockdown_from_offchain: false,
1217 local_tx_signed: false,
1219 last_block_hash: Default::default(),
1220 secp_ctx: Secp256k1::new(),
1224 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
1225 /// needed by local commitment transactions HTCLs nor by remote ones. Unless we haven't already seen remote
1226 /// commitment transaction's secret, they are de facto pruned (we can use revocation key).
1227 pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
1228 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
1229 return Err(MonitorUpdateError("Previous secret did not match new one"));
1232 // Prune HTLCs from the previous remote commitment tx so we don't generate failure/fulfill
1233 // events for now-revoked/fulfilled HTLCs.
1234 if let Some(txid) = self.prev_remote_commitment_txid.take() {
1235 for &mut (_, ref mut source) in self.remote_claimable_outpoints.get_mut(&txid).unwrap() {
1240 if !self.payment_preimages.is_empty() {
1241 let cur_local_signed_commitment_tx = &self.current_local_commitment_tx;
1242 let prev_local_signed_commitment_tx = self.prev_local_signed_commitment_tx.as_ref();
1243 let min_idx = self.get_min_seen_secret();
1244 let remote_hash_commitment_number = &mut self.remote_hash_commitment_number;
1246 self.payment_preimages.retain(|&k, _| {
1247 for &(ref htlc, _, _) in cur_local_signed_commitment_tx.htlc_outputs.iter() {
1248 if k == htlc.payment_hash {
1252 if let Some(prev_local_commitment_tx) = prev_local_signed_commitment_tx {
1253 for &(ref htlc, _, _) in prev_local_commitment_tx.htlc_outputs.iter() {
1254 if k == htlc.payment_hash {
1259 let contains = if let Some(cn) = remote_hash_commitment_number.get(&k) {
1266 remote_hash_commitment_number.remove(&k);
1275 /// Informs this monitor of the latest remote (ie non-broadcastable) commitment transaction.
1276 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
1277 /// possibly future revocation/preimage information) to claim outputs where possible.
1278 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
1279 pub(super) fn provide_latest_remote_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 {
1280 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
1281 // so that a remote monitor doesn't learn anything unless there is a malicious close.
1282 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
1284 for &(ref htlc, _) in &htlc_outputs {
1285 self.remote_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
1288 let new_txid = unsigned_commitment_tx.txid();
1289 log_trace!(logger, "Tracking new remote commitment transaction with txid {} at commitment number {} with {} HTLC outputs", new_txid, commitment_number, htlc_outputs.len());
1290 log_trace!(logger, "New potential remote commitment transaction: {}", encode::serialize_hex(unsigned_commitment_tx));
1291 self.prev_remote_commitment_txid = self.current_remote_commitment_txid.take();
1292 self.current_remote_commitment_txid = Some(new_txid);
1293 self.remote_claimable_outpoints.insert(new_txid, htlc_outputs.clone());
1294 self.current_remote_commitment_number = commitment_number;
1295 //TODO: Merge this into the other per-remote-transaction output storage stuff
1296 match self.their_cur_revocation_points {
1297 Some(old_points) => {
1298 if old_points.0 == commitment_number + 1 {
1299 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
1300 } else if old_points.0 == commitment_number + 2 {
1301 if let Some(old_second_point) = old_points.2 {
1302 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
1304 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1307 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1311 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1314 let mut htlcs = Vec::with_capacity(htlc_outputs.len());
1315 for htlc in htlc_outputs {
1316 if htlc.0.transaction_output_index.is_some() {
1320 self.remote_tx_cache.per_htlc.insert(new_txid, htlcs);
1323 /// Informs this monitor of the latest local (ie broadcastable) commitment transaction. The
1324 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
1325 /// is important that any clones of this channel monitor (including remote clones) by kept
1326 /// up-to-date as our local commitment transaction is updated.
1327 /// Panics if set_on_local_tx_csv has never been called.
1328 pub(super) fn provide_latest_local_commitment_tx_info(&mut self, commitment_tx: LocalCommitmentTransaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), MonitorUpdateError> {
1329 if self.local_tx_signed {
1330 return Err(MonitorUpdateError("A local commitment tx has already been signed, no new local commitment txn can be sent to our counterparty"));
1332 let txid = commitment_tx.txid();
1333 let sequence = commitment_tx.unsigned_tx.input[0].sequence as u64;
1334 let locktime = commitment_tx.unsigned_tx.lock_time as u64;
1335 let mut new_local_commitment_tx = LocalSignedTx {
1337 revocation_key: commitment_tx.local_keys.revocation_key,
1338 a_htlc_key: commitment_tx.local_keys.a_htlc_key,
1339 b_htlc_key: commitment_tx.local_keys.b_htlc_key,
1340 delayed_payment_key: commitment_tx.local_keys.a_delayed_payment_key,
1341 per_commitment_point: commitment_tx.local_keys.per_commitment_point,
1342 feerate_per_kw: commitment_tx.feerate_per_kw,
1343 htlc_outputs: htlc_outputs,
1345 // Returning a monitor error before updating tracking points means in case of using
1346 // a concurrent watchtower implementation for same channel, if this one doesn't
1347 // reject update as we do, you MAY have the latest local valid commitment tx onchain
1348 // for which you want to spend outputs. We're NOT robust again this scenario right
1349 // now but we should consider it later.
1350 if let Err(_) = self.onchain_tx_handler.provide_latest_local_tx(commitment_tx) {
1351 return Err(MonitorUpdateError("Local commitment signed has already been signed, no further update of LOCAL commitment transaction is allowed"));
1353 self.current_local_commitment_number = 0xffff_ffff_ffff - ((((sequence & 0xffffff) << 3*8) | (locktime as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
1354 mem::swap(&mut new_local_commitment_tx, &mut self.current_local_commitment_tx);
1355 self.prev_local_signed_commitment_tx = Some(new_local_commitment_tx);
1359 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
1360 /// commitment_tx_infos which contain the payment hash have been revoked.
1361 pub(super) fn provide_payment_preimage(&mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage) {
1362 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
1365 pub(super) fn broadcast_latest_local_commitment_txn<B: Deref, L: Deref>(&mut self, broadcaster: &B, logger: &L)
1366 where B::Target: BroadcasterInterface,
1369 for tx in self.get_latest_local_commitment_txn(logger).iter() {
1370 broadcaster.broadcast_transaction(tx);
1372 self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0));
1375 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
1378 /// panics if the given update is not the next update by update_id.
1379 pub fn update_monitor<B: Deref, L: Deref>(&mut self, mut updates: ChannelMonitorUpdate, broadcaster: &B, logger: &L) -> Result<(), MonitorUpdateError>
1380 where B::Target: BroadcasterInterface,
1383 if self.latest_update_id + 1 != updates.update_id {
1384 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
1386 for update in updates.updates.drain(..) {
1388 ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { commitment_tx, htlc_outputs } => {
1389 if self.lockdown_from_offchain { panic!(); }
1390 self.provide_latest_local_commitment_tx_info(commitment_tx, htlc_outputs)?
1392 ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
1393 self.provide_latest_remote_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point, logger),
1394 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
1395 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
1396 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
1397 self.provide_secret(idx, secret)?,
1398 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
1399 self.lockdown_from_offchain = true;
1400 if should_broadcast {
1401 self.broadcast_latest_local_commitment_txn(broadcaster, logger);
1403 log_error!(logger, "You have a toxic local commitment transaction avaible in channel monitor, read comment in ChannelMonitor::get_latest_local_commitment_txn to be informed of manual action to take");
1408 self.latest_update_id = updates.update_id;
1412 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
1414 pub fn get_latest_update_id(&self) -> u64 {
1415 self.latest_update_id
1418 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
1419 pub fn get_funding_txo(&self) -> &(OutPoint, Script) {
1423 /// Gets a list of txids, with their output scripts (in the order they appear in the
1424 /// transaction), which we must learn about spends of via block_connected().
1425 pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<Script>> {
1426 &self.outputs_to_watch
1429 /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
1430 /// Generally useful when deserializing as during normal operation the return values of
1431 /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
1432 /// that the get_funding_txo outpoint and transaction must also be monitored for!).
1433 pub fn get_monitored_outpoints(&self) -> Vec<(Txid, u32, &Script)> {
1434 let mut res = Vec::with_capacity(self.remote_commitment_txn_on_chain.len() * 2);
1435 for (ref txid, &(_, ref outputs)) in self.remote_commitment_txn_on_chain.iter() {
1436 for (idx, output) in outputs.iter().enumerate() {
1437 res.push(((*txid).clone(), idx as u32, output));
1443 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1444 /// ChannelManager via ManyChannelMonitor::get_and_clear_pending_monitor_events().
1445 pub fn get_and_clear_pending_monitor_events(&mut self) -> Vec<MonitorEvent> {
1446 let mut ret = Vec::new();
1447 mem::swap(&mut ret, &mut self.pending_monitor_events);
1451 /// Gets the list of pending events which were generated by previous actions, clearing the list
1454 /// This is called by ManyChannelMonitor::get_and_clear_pending_events() and is equivalent to
1455 /// EventsProvider::get_and_clear_pending_events() except that it requires &mut self as we do
1456 /// no internal locking in ChannelMonitors.
1457 pub fn get_and_clear_pending_events(&mut self) -> Vec<Event> {
1458 let mut ret = Vec::new();
1459 mem::swap(&mut ret, &mut self.pending_events);
1463 /// Can only fail if idx is < get_min_seen_secret
1464 pub(super) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
1465 self.commitment_secrets.get_secret(idx)
1468 pub(super) fn get_min_seen_secret(&self) -> u64 {
1469 self.commitment_secrets.get_min_seen_secret()
1472 pub(super) fn get_cur_remote_commitment_number(&self) -> u64 {
1473 self.current_remote_commitment_number
1476 pub(super) fn get_cur_local_commitment_number(&self) -> u64 {
1477 self.current_local_commitment_number
1480 /// Attempts to claim a remote commitment transaction's outputs using the revocation key and
1481 /// data in remote_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
1482 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
1483 /// HTLC-Success/HTLC-Timeout transactions.
1484 /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
1485 /// revoked remote commitment tx
1486 fn check_spend_remote_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) where L::Target: Logger {
1487 // Most secp and related errors trying to create keys means we have no hope of constructing
1488 // a spend transaction...so we return no transactions to broadcast
1489 let mut claimable_outpoints = Vec::new();
1490 let mut watch_outputs = Vec::new();
1492 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1493 let per_commitment_option = self.remote_claimable_outpoints.get(&commitment_txid);
1495 macro_rules! ignore_error {
1496 ( $thing : expr ) => {
1499 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs))
1504 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);
1505 if commitment_number >= self.get_min_seen_secret() {
1506 let secret = self.get_secret(commitment_number).unwrap();
1507 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1508 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1509 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.keys.pubkeys().revocation_basepoint));
1510 let delayed_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key), &self.remote_tx_cache.remote_delayed_payment_base_key));
1512 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.remote_tx_cache.on_remote_tx_csv, &delayed_key);
1513 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1515 // First, process non-htlc outputs (to_local & to_remote)
1516 for (idx, outp) in tx.output.iter().enumerate() {
1517 if outp.script_pubkey == revokeable_p2wsh {
1518 let witness_data = InputMaterial::Revoked { per_commitment_point, remote_delayed_payment_base_key: self.remote_tx_cache.remote_delayed_payment_base_key, remote_htlc_base_key: self.remote_tx_cache.remote_htlc_base_key, per_commitment_key, input_descriptor: InputDescriptors::RevokedOutput, amount: outp.value, htlc: None, on_remote_tx_csv: self.remote_tx_cache.on_remote_tx_csv};
1519 claimable_outpoints.push(ClaimRequest { absolute_timelock: height + self.remote_tx_cache.on_remote_tx_csv as u32, aggregable: true, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: idx as u32 }, witness_data});
1523 // Then, try to find revoked htlc outputs
1524 if let Some(ref per_commitment_data) = per_commitment_option {
1525 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1526 if let Some(transaction_output_index) = htlc.transaction_output_index {
1527 if transaction_output_index as usize >= tx.output.len() ||
1528 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1529 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1531 let witness_data = InputMaterial::Revoked { per_commitment_point, remote_delayed_payment_base_key: self.remote_tx_cache.remote_delayed_payment_base_key, remote_htlc_base_key: self.remote_tx_cache.remote_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_remote_tx_csv: self.remote_tx_cache.on_remote_tx_csv};
1532 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable: true, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1537 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
1538 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
1539 // We're definitely a remote commitment transaction!
1540 log_trace!(logger, "Got broadcast of revoked remote commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
1541 watch_outputs.append(&mut tx.output.clone());
1542 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1544 macro_rules! check_htlc_fails {
1545 ($txid: expr, $commitment_tx: expr) => {
1546 if let Some(ref outpoints) = self.remote_claimable_outpoints.get($txid) {
1547 for &(ref htlc, ref source_option) in outpoints.iter() {
1548 if let &Some(ref source) = source_option {
1549 log_info!(logger, "Failing HTLC with payment_hash {} from {} remote commitment tx due to broadcast of revoked remote commitment transaction, waiting for confirmation (at height {})", log_bytes!(htlc.payment_hash.0), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1550 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1551 hash_map::Entry::Occupied(mut entry) => {
1552 let e = entry.get_mut();
1553 e.retain(|ref event| {
1555 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1556 return htlc_update.0 != **source
1561 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1563 hash_map::Entry::Vacant(entry) => {
1564 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1572 if let Some(ref txid) = self.current_remote_commitment_txid {
1573 check_htlc_fails!(txid, "current");
1575 if let Some(ref txid) = self.prev_remote_commitment_txid {
1576 check_htlc_fails!(txid, "remote");
1578 // No need to check local commitment txn, symmetric HTLCSource must be present as per-htlc data on remote commitment tx
1580 } else if let Some(per_commitment_data) = per_commitment_option {
1581 // While this isn't useful yet, there is a potential race where if a counterparty
1582 // revokes a state at the same time as the commitment transaction for that state is
1583 // confirmed, and the watchtower receives the block before the user, the user could
1584 // upload a new ChannelMonitor with the revocation secret but the watchtower has
1585 // already processed the block, resulting in the remote_commitment_txn_on_chain entry
1586 // not being generated by the above conditional. Thus, to be safe, we go ahead and
1588 watch_outputs.append(&mut tx.output.clone());
1589 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1591 log_trace!(logger, "Got broadcast of non-revoked remote commitment transaction {}", commitment_txid);
1593 macro_rules! check_htlc_fails {
1594 ($txid: expr, $commitment_tx: expr, $id: tt) => {
1595 if let Some(ref latest_outpoints) = self.remote_claimable_outpoints.get($txid) {
1596 $id: for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1597 if let &Some(ref source) = source_option {
1598 // Check if the HTLC is present in the commitment transaction that was
1599 // broadcast, but not if it was below the dust limit, which we should
1600 // fail backwards immediately as there is no way for us to learn the
1601 // payment_preimage.
1602 // Note that if the dust limit were allowed to change between
1603 // commitment transactions we'd want to be check whether *any*
1604 // broadcastable commitment transaction has the HTLC in it, but it
1605 // cannot currently change after channel initialization, so we don't
1607 for &(ref broadcast_htlc, ref broadcast_source) in per_commitment_data.iter() {
1608 if broadcast_htlc.transaction_output_index.is_some() && Some(source) == broadcast_source.as_ref() {
1612 log_trace!(logger, "Failing HTLC with payment_hash {} from {} remote commitment tx due to broadcast of remote commitment transaction", log_bytes!(htlc.payment_hash.0), $commitment_tx);
1613 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1614 hash_map::Entry::Occupied(mut entry) => {
1615 let e = entry.get_mut();
1616 e.retain(|ref event| {
1618 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1619 return htlc_update.0 != **source
1624 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1626 hash_map::Entry::Vacant(entry) => {
1627 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1635 if let Some(ref txid) = self.current_remote_commitment_txid {
1636 check_htlc_fails!(txid, "current", 'current_loop);
1638 if let Some(ref txid) = self.prev_remote_commitment_txid {
1639 check_htlc_fails!(txid, "previous", 'prev_loop);
1642 if let Some(revocation_points) = self.their_cur_revocation_points {
1643 let revocation_point_option =
1644 if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1645 else if let Some(point) = revocation_points.2.as_ref() {
1646 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1648 if let Some(revocation_point) = revocation_point_option {
1649 self.remote_payment_script = {
1650 // Note that the Network here is ignored as we immediately drop the address for the
1651 // script_pubkey version
1652 let payment_hash160 = WPubkeyHash::hash(&self.keys.pubkeys().payment_point.serialize());
1653 Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_hash160[..]).into_script()
1656 // Then, try to find htlc outputs
1657 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1658 if let Some(transaction_output_index) = htlc.transaction_output_index {
1659 if transaction_output_index as usize >= tx.output.len() ||
1660 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1661 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1663 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
1664 let aggregable = if !htlc.offered { false } else { true };
1665 if preimage.is_some() || !htlc.offered {
1666 let witness_data = InputMaterial::RemoteHTLC { per_commitment_point: *revocation_point, remote_delayed_payment_base_key: self.remote_tx_cache.remote_delayed_payment_base_key, remote_htlc_base_key: self.remote_tx_cache.remote_htlc_base_key, preimage, htlc: htlc.clone() };
1667 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1674 (claimable_outpoints, (commitment_txid, watch_outputs))
1677 /// Attempts to claim a remote HTLC-Success/HTLC-Timeout's outputs using the revocation key
1678 fn check_spend_remote_htlc<L: Deref>(&mut self, tx: &Transaction, commitment_number: u64, height: u32, logger: &L) -> (Vec<ClaimRequest>, Option<(Txid, Vec<TxOut>)>) where L::Target: Logger {
1679 let htlc_txid = tx.txid();
1680 if tx.input.len() != 1 || tx.output.len() != 1 || tx.input[0].witness.len() != 5 {
1681 return (Vec::new(), None)
1684 macro_rules! ignore_error {
1685 ( $thing : expr ) => {
1688 Err(_) => return (Vec::new(), None)
1693 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
1694 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1695 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1697 log_trace!(logger, "Remote HTLC broadcast {}:{}", htlc_txid, 0);
1698 let witness_data = InputMaterial::Revoked { per_commitment_point, remote_delayed_payment_base_key: self.remote_tx_cache.remote_delayed_payment_base_key, remote_htlc_base_key: self.remote_tx_cache.remote_htlc_base_key, per_commitment_key, input_descriptor: InputDescriptors::RevokedOutput, amount: tx.output[0].value, htlc: None, on_remote_tx_csv: self.remote_tx_cache.on_remote_tx_csv };
1699 let claimable_outpoints = vec!(ClaimRequest { absolute_timelock: height + self.remote_tx_cache.on_remote_tx_csv as u32, aggregable: true, outpoint: BitcoinOutPoint { txid: htlc_txid, vout: 0}, witness_data });
1700 (claimable_outpoints, Some((htlc_txid, tx.output.clone())))
1703 fn broadcast_by_local_state(&self, commitment_tx: &Transaction, local_tx: &LocalSignedTx) -> (Vec<ClaimRequest>, Vec<TxOut>, Option<(Script, PublicKey, PublicKey)>) {
1704 let mut claim_requests = Vec::with_capacity(local_tx.htlc_outputs.len());
1705 let mut watch_outputs = Vec::with_capacity(local_tx.htlc_outputs.len());
1707 let redeemscript = chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.on_local_tx_csv, &local_tx.delayed_payment_key);
1708 let broadcasted_local_revokable_script = Some((redeemscript.to_v0_p2wsh(), local_tx.per_commitment_point.clone(), local_tx.revocation_key.clone()));
1710 for &(ref htlc, _, _) in local_tx.htlc_outputs.iter() {
1711 if let Some(transaction_output_index) = htlc.transaction_output_index {
1712 claim_requests.push(ClaimRequest { absolute_timelock: ::std::u32::MAX, aggregable: false, outpoint: BitcoinOutPoint { txid: local_tx.txid, vout: transaction_output_index as u32 },
1713 witness_data: InputMaterial::LocalHTLC {
1714 preimage: if !htlc.offered {
1715 if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1716 Some(preimage.clone())
1718 // We can't build an HTLC-Success transaction without the preimage
1722 amount: htlc.amount_msat,
1724 watch_outputs.push(commitment_tx.output[transaction_output_index as usize].clone());
1728 (claim_requests, watch_outputs, broadcasted_local_revokable_script)
1731 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1732 /// revoked using data in local_claimable_outpoints.
1733 /// Should not be used if check_spend_revoked_transaction succeeds.
1734 fn check_spend_local_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) where L::Target: Logger {
1735 let commitment_txid = tx.txid();
1736 let mut claim_requests = Vec::new();
1737 let mut watch_outputs = Vec::new();
1739 macro_rules! wait_threshold_conf {
1740 ($height: expr, $source: expr, $commitment_tx: expr, $payment_hash: expr) => {
1741 log_trace!(logger, "Failing HTLC with payment_hash {} from {} local commitment tx due to broadcast of transaction, waiting confirmation (at height{})", log_bytes!($payment_hash.0), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1742 match self.onchain_events_waiting_threshold_conf.entry($height + ANTI_REORG_DELAY - 1) {
1743 hash_map::Entry::Occupied(mut entry) => {
1744 let e = entry.get_mut();
1745 e.retain(|ref event| {
1747 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1748 return htlc_update.0 != $source
1753 e.push(OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)});
1755 hash_map::Entry::Vacant(entry) => {
1756 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)}]);
1762 macro_rules! append_onchain_update {
1763 ($updates: expr) => {
1764 claim_requests = $updates.0;
1765 watch_outputs.append(&mut $updates.1);
1766 self.broadcasted_local_revokable_script = $updates.2;
1770 // HTLCs set may differ between last and previous local commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
1771 let mut is_local_tx = false;
1773 if self.current_local_commitment_tx.txid == commitment_txid {
1775 log_trace!(logger, "Got latest local commitment tx broadcast, searching for available HTLCs to claim");
1776 let mut res = self.broadcast_by_local_state(tx, &self.current_local_commitment_tx);
1777 append_onchain_update!(res);
1778 } else if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1779 if local_tx.txid == commitment_txid {
1781 log_trace!(logger, "Got previous local commitment tx broadcast, searching for available HTLCs to claim");
1782 let mut res = self.broadcast_by_local_state(tx, local_tx);
1783 append_onchain_update!(res);
1787 macro_rules! fail_dust_htlcs_after_threshold_conf {
1788 ($local_tx: expr) => {
1789 for &(ref htlc, _, ref source) in &$local_tx.htlc_outputs {
1790 if htlc.transaction_output_index.is_none() {
1791 if let &Some(ref source) = source {
1792 wait_threshold_conf!(height, source.clone(), "lastest", htlc.payment_hash.clone());
1800 fail_dust_htlcs_after_threshold_conf!(self.current_local_commitment_tx);
1801 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1802 fail_dust_htlcs_after_threshold_conf!(local_tx);
1806 (claim_requests, (commitment_txid, watch_outputs))
1809 /// Used by ChannelManager deserialization to broadcast the latest local state if its copy of
1810 /// the Channel was out-of-date. You may use it to get a broadcastable local toxic tx in case of
1811 /// fallen-behind, i.e when receiving a channel_reestablish with a proof that our remote side knows
1812 /// a higher revocation secret than the local commitment number we are aware of. Broadcasting these
1813 /// transactions are UNSAFE, as they allow remote side to punish you. Nevertheless you may want to
1814 /// broadcast them if remote don't close channel with his higher commitment transaction after a
1815 /// substantial amount of time (a month or even a year) to get back funds. Best may be to contact
1816 /// out-of-band the other node operator to coordinate with him if option is available to you.
1817 /// In any-case, choice is up to the user.
1818 pub fn get_latest_local_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1819 log_trace!(logger, "Getting signed latest local commitment transaction!");
1820 self.local_tx_signed = true;
1821 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_local_tx(&self.funding_redeemscript) {
1822 let txid = commitment_tx.txid();
1823 let mut res = vec![commitment_tx];
1824 for htlc in self.current_local_commitment_tx.htlc_outputs.iter() {
1825 if let Some(vout) = htlc.0.transaction_output_index {
1826 let preimage = if !htlc.0.offered {
1827 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1828 // We can't build an HTLC-Success transaction without the preimage
1832 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
1833 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1838 // 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.
1839 // The data will be re-generated and tracked in check_spend_local_transaction if we get a confirmation.
1845 /// Unsafe test-only version of get_latest_local_commitment_txn used by our test framework
1846 /// to bypass LocalCommitmentTransaction state update lockdown after signature and generate
1847 /// revoked commitment transaction.
1848 #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]
1849 pub fn unsafe_get_latest_local_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1850 log_trace!(logger, "Getting signed copy of latest local commitment transaction!");
1851 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_copy_local_tx(&self.funding_redeemscript) {
1852 let txid = commitment_tx.txid();
1853 let mut res = vec![commitment_tx];
1854 for htlc in self.current_local_commitment_tx.htlc_outputs.iter() {
1855 if let Some(vout) = htlc.0.transaction_output_index {
1856 let preimage = if !htlc.0.offered {
1857 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1858 // We can't build an HTLC-Success transaction without the preimage
1862 if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
1863 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1873 /// Called by SimpleManyChannelMonitor::block_connected, which implements
1874 /// ChainListener::block_connected.
1875 /// Eventually this should be pub and, roughly, implement ChainListener, however this requires
1876 /// &mut self, as well as returns new spendable outputs and outpoints to watch for spending of
1878 fn block_connected<B: Deref, F: Deref, L: Deref>(&mut self, txn_matched: &[&Transaction], height: u32, block_hash: &BlockHash, broadcaster: B, fee_estimator: F, logger: L)-> Vec<(Txid, Vec<TxOut>)>
1879 where B::Target: BroadcasterInterface,
1880 F::Target: FeeEstimator,
1883 for tx in txn_matched {
1884 let mut output_val = 0;
1885 for out in tx.output.iter() {
1886 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1887 output_val += out.value;
1888 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1892 log_trace!(logger, "Block {} at height {} connected with {} txn matched", block_hash, height, txn_matched.len());
1893 let mut watch_outputs = Vec::new();
1894 let mut claimable_outpoints = Vec::new();
1895 for tx in txn_matched {
1896 if tx.input.len() == 1 {
1897 // Assuming our keys were not leaked (in which case we're screwed no matter what),
1898 // commitment transactions and HTLC transactions will all only ever have one input,
1899 // which is an easy way to filter out any potential non-matching txn for lazy
1901 let prevout = &tx.input[0].previous_output;
1902 if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
1903 if (tx.input[0].sequence >> 8*3) as u8 == 0x80 && (tx.lock_time >> 8*3) as u8 == 0x20 {
1904 let (mut new_outpoints, new_outputs) = self.check_spend_remote_transaction(&tx, height, &logger);
1905 if !new_outputs.1.is_empty() {
1906 watch_outputs.push(new_outputs);
1908 if new_outpoints.is_empty() {
1909 let (mut new_outpoints, new_outputs) = self.check_spend_local_transaction(&tx, height, &logger);
1910 if !new_outputs.1.is_empty() {
1911 watch_outputs.push(new_outputs);
1913 claimable_outpoints.append(&mut new_outpoints);
1915 claimable_outpoints.append(&mut new_outpoints);
1918 if let Some(&(commitment_number, _)) = self.remote_commitment_txn_on_chain.get(&prevout.txid) {
1919 let (mut new_outpoints, new_outputs_option) = self.check_spend_remote_htlc(&tx, commitment_number, height, &logger);
1920 claimable_outpoints.append(&mut new_outpoints);
1921 if let Some(new_outputs) = new_outputs_option {
1922 watch_outputs.push(new_outputs);
1927 // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
1928 // can also be resolved in a few other ways which can have more than one output. Thus,
1929 // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
1930 self.is_resolving_htlc_output(&tx, height, &logger);
1932 self.is_paying_spendable_output(&tx, height, &logger);
1934 let should_broadcast = self.would_broadcast_at_height(height, &logger);
1935 if should_broadcast {
1936 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() }});
1938 if should_broadcast {
1939 self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0));
1940 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_local_tx(&self.funding_redeemscript) {
1941 self.local_tx_signed = true;
1942 let (mut new_outpoints, new_outputs, _) = self.broadcast_by_local_state(&commitment_tx, &self.current_local_commitment_tx);
1943 if !new_outputs.is_empty() {
1944 watch_outputs.push((self.current_local_commitment_tx.txid.clone(), new_outputs));
1946 claimable_outpoints.append(&mut new_outpoints);
1949 if let Some(events) = self.onchain_events_waiting_threshold_conf.remove(&height) {
1952 OnchainEvent::HTLCUpdate { htlc_update } => {
1953 log_trace!(logger, "HTLC {} failure update has got enough confirmations to be passed upstream", log_bytes!((htlc_update.1).0));
1954 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
1955 payment_hash: htlc_update.1,
1956 payment_preimage: None,
1957 source: htlc_update.0,
1960 OnchainEvent::MaturingOutput { descriptor } => {
1961 log_trace!(logger, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
1962 self.pending_events.push(Event::SpendableOutputs {
1963 outputs: vec![descriptor]
1970 self.onchain_tx_handler.block_connected(txn_matched, claimable_outpoints, height, &*broadcaster, &*fee_estimator, &*logger);
1972 self.last_block_hash = block_hash.clone();
1973 for &(ref txid, ref output_scripts) in watch_outputs.iter() {
1974 self.outputs_to_watch.insert(txid.clone(), output_scripts.iter().map(|o| o.script_pubkey.clone()).collect());
1980 fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, height: u32, block_hash: &BlockHash, broadcaster: B, fee_estimator: F, logger: L)
1981 where B::Target: BroadcasterInterface,
1982 F::Target: FeeEstimator,
1985 log_trace!(logger, "Block {} at height {} disconnected", block_hash, height);
1986 if let Some(_) = self.onchain_events_waiting_threshold_conf.remove(&(height + ANTI_REORG_DELAY - 1)) {
1988 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
1989 //- maturing spendable output has transaction paying us has been disconnected
1992 self.onchain_tx_handler.block_disconnected(height, broadcaster, fee_estimator, logger);
1994 self.last_block_hash = block_hash.clone();
1997 fn would_broadcast_at_height<L: Deref>(&self, height: u32, logger: &L) -> bool where L::Target: Logger {
1998 // We need to consider all HTLCs which are:
1999 // * in any unrevoked remote commitment transaction, as they could broadcast said
2000 // transactions and we'd end up in a race, or
2001 // * are in our latest local commitment transaction, as this is the thing we will
2002 // broadcast if we go on-chain.
2003 // Note that we consider HTLCs which were below dust threshold here - while they don't
2004 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
2005 // to the source, and if we don't fail the channel we will have to ensure that the next
2006 // updates that peer sends us are update_fails, failing the channel if not. It's probably
2007 // easier to just fail the channel as this case should be rare enough anyway.
2008 macro_rules! scan_commitment {
2009 ($htlcs: expr, $local_tx: expr) => {
2010 for ref htlc in $htlcs {
2011 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
2012 // chain with enough room to claim the HTLC without our counterparty being able to
2013 // time out the HTLC first.
2014 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
2015 // concern is being able to claim the corresponding inbound HTLC (on another
2016 // channel) before it expires. In fact, we don't even really care if our
2017 // counterparty here claims such an outbound HTLC after it expired as long as we
2018 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
2019 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
2020 // we give ourselves a few blocks of headroom after expiration before going
2021 // on-chain for an expired HTLC.
2022 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
2023 // from us until we've reached the point where we go on-chain with the
2024 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
2025 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
2026 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
2027 // inbound_cltv == height + CLTV_CLAIM_BUFFER
2028 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
2029 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
2030 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
2031 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
2032 // The final, above, condition is checked for statically in channelmanager
2033 // with CHECK_CLTV_EXPIRY_SANITY_2.
2034 let htlc_outbound = $local_tx == htlc.offered;
2035 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
2036 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
2037 log_info!(logger, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
2044 scan_commitment!(self.current_local_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
2046 if let Some(ref txid) = self.current_remote_commitment_txid {
2047 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(txid) {
2048 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2051 if let Some(ref txid) = self.prev_remote_commitment_txid {
2052 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(txid) {
2053 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2060 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a local
2061 /// or remote commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
2062 fn is_resolving_htlc_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2063 'outer_loop: for input in &tx.input {
2064 let mut payment_data = None;
2065 let revocation_sig_claim = (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && input.witness[1].len() == 33)
2066 || (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && input.witness[1].len() == 33);
2067 let accepted_preimage_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::AcceptedHTLC);
2068 let offered_preimage_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC);
2070 macro_rules! log_claim {
2071 ($tx_info: expr, $local_tx: expr, $htlc: expr, $source_avail: expr) => {
2072 // We found the output in question, but aren't failing it backwards
2073 // as we have no corresponding source and no valid remote commitment txid
2074 // to try a weak source binding with same-hash, same-value still-valid offered HTLC.
2075 // This implies either it is an inbound HTLC or an outbound HTLC on a revoked transaction.
2076 let outbound_htlc = $local_tx == $htlc.offered;
2077 if ($local_tx && revocation_sig_claim) ||
2078 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
2079 log_error!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
2080 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2081 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2082 if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back" });
2084 log_info!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
2085 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2086 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2087 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
2092 macro_rules! check_htlc_valid_remote {
2093 ($remote_txid: expr, $htlc_output: expr) => {
2094 if let Some(txid) = $remote_txid {
2095 for &(ref pending_htlc, ref pending_source) in self.remote_claimable_outpoints.get(&txid).unwrap() {
2096 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
2097 if let &Some(ref source) = pending_source {
2098 log_claim!("revoked remote commitment tx", false, pending_htlc, true);
2099 payment_data = Some(((**source).clone(), $htlc_output.payment_hash));
2108 macro_rules! scan_commitment {
2109 ($htlcs: expr, $tx_info: expr, $local_tx: expr) => {
2110 for (ref htlc_output, source_option) in $htlcs {
2111 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
2112 if let Some(ref source) = source_option {
2113 log_claim!($tx_info, $local_tx, htlc_output, true);
2114 // We have a resolution of an HTLC either from one of our latest
2115 // local commitment transactions or an unrevoked remote commitment
2116 // transaction. This implies we either learned a preimage, the HTLC
2117 // has timed out, or we screwed up. In any case, we should now
2118 // resolve the source HTLC with the original sender.
2119 payment_data = Some(((*source).clone(), htlc_output.payment_hash));
2120 } else if !$local_tx {
2121 check_htlc_valid_remote!(self.current_remote_commitment_txid, htlc_output);
2122 if payment_data.is_none() {
2123 check_htlc_valid_remote!(self.prev_remote_commitment_txid, htlc_output);
2126 if payment_data.is_none() {
2127 log_claim!($tx_info, $local_tx, htlc_output, false);
2128 continue 'outer_loop;
2135 if input.previous_output.txid == self.current_local_commitment_tx.txid {
2136 scan_commitment!(self.current_local_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2137 "our latest local commitment tx", true);
2139 if let Some(ref prev_local_signed_commitment_tx) = self.prev_local_signed_commitment_tx {
2140 if input.previous_output.txid == prev_local_signed_commitment_tx.txid {
2141 scan_commitment!(prev_local_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2142 "our previous local commitment tx", true);
2145 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(&input.previous_output.txid) {
2146 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
2147 "remote commitment tx", false);
2150 // Check that scan_commitment, above, decided there is some source worth relaying an
2151 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
2152 if let Some((source, payment_hash)) = payment_data {
2153 let mut payment_preimage = PaymentPreimage([0; 32]);
2154 if accepted_preimage_claim {
2155 if !self.pending_monitor_events.iter().any(
2156 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update { upd.source == source } else { false }) {
2157 payment_preimage.0.copy_from_slice(&input.witness[3]);
2158 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2160 payment_preimage: Some(payment_preimage),
2164 } else if offered_preimage_claim {
2165 if !self.pending_monitor_events.iter().any(
2166 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update {
2167 upd.source == source
2169 payment_preimage.0.copy_from_slice(&input.witness[1]);
2170 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2172 payment_preimage: Some(payment_preimage),
2177 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);
2178 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2179 hash_map::Entry::Occupied(mut entry) => {
2180 let e = entry.get_mut();
2181 e.retain(|ref event| {
2183 OnchainEvent::HTLCUpdate { ref htlc_update } => {
2184 return htlc_update.0 != source
2189 e.push(OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)});
2191 hash_map::Entry::Vacant(entry) => {
2192 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)}]);
2200 /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
2201 fn is_paying_spendable_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2202 let mut spendable_output = None;
2203 for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
2204 if i > ::std::u16::MAX as usize {
2205 // While it is possible that an output exists on chain which is greater than the
2206 // 2^16th output in a given transaction, this is only possible if the output is not
2207 // in a lightning transaction and was instead placed there by some third party who
2208 // wishes to give us money for no reason.
2209 // Namely, any lightning transactions which we pre-sign will never have anywhere
2210 // near 2^16 outputs both because such transactions must have ~2^16 outputs who's
2211 // scripts are not longer than one byte in length and because they are inherently
2212 // non-standard due to their size.
2213 // Thus, it is completely safe to ignore such outputs, and while it may result in
2214 // us ignoring non-lightning fund to us, that is only possible if someone fills
2215 // nearly a full block with garbage just to hit this case.
2218 if outp.script_pubkey == self.destination_script {
2219 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2220 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2221 output: outp.clone(),
2224 } else if let Some(ref broadcasted_local_revokable_script) = self.broadcasted_local_revokable_script {
2225 if broadcasted_local_revokable_script.0 == outp.script_pubkey {
2226 spendable_output = Some(SpendableOutputDescriptor::DynamicOutputP2WSH {
2227 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2228 per_commitment_point: broadcasted_local_revokable_script.1,
2229 to_self_delay: self.on_local_tx_csv,
2230 output: outp.clone(),
2231 key_derivation_params: self.keys.key_derivation_params(),
2232 remote_revocation_pubkey: broadcasted_local_revokable_script.2.clone(),
2236 } else if self.remote_payment_script == outp.script_pubkey {
2237 spendable_output = Some(SpendableOutputDescriptor::StaticOutputRemotePayment {
2238 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2239 output: outp.clone(),
2240 key_derivation_params: self.keys.key_derivation_params(),
2243 } else if outp.script_pubkey == self.shutdown_script {
2244 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2245 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2246 output: outp.clone(),
2250 if let Some(spendable_output) = spendable_output {
2251 log_trace!(logger, "Maturing {} until {}", log_spendable!(spendable_output), height + ANTI_REORG_DELAY - 1);
2252 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2253 hash_map::Entry::Occupied(mut entry) => {
2254 let e = entry.get_mut();
2255 e.push(OnchainEvent::MaturingOutput { descriptor: spendable_output });
2257 hash_map::Entry::Vacant(entry) => {
2258 entry.insert(vec![OnchainEvent::MaturingOutput { descriptor: spendable_output }]);
2265 const MAX_ALLOC_SIZE: usize = 64*1024;
2267 impl<ChanSigner: ChannelKeys + Readable> Readable for (BlockHash, ChannelMonitor<ChanSigner>) {
2268 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
2269 macro_rules! unwrap_obj {
2273 Err(_) => return Err(DecodeError::InvalidValue),
2278 let _ver: u8 = Readable::read(reader)?;
2279 let min_ver: u8 = Readable::read(reader)?;
2280 if min_ver > SERIALIZATION_VERSION {
2281 return Err(DecodeError::UnknownVersion);
2284 let latest_update_id: u64 = Readable::read(reader)?;
2285 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
2287 let destination_script = Readable::read(reader)?;
2288 let broadcasted_local_revokable_script = match <u8 as Readable>::read(reader)? {
2290 let revokable_address = Readable::read(reader)?;
2291 let per_commitment_point = Readable::read(reader)?;
2292 let revokable_script = Readable::read(reader)?;
2293 Some((revokable_address, per_commitment_point, revokable_script))
2296 _ => return Err(DecodeError::InvalidValue),
2298 let remote_payment_script = Readable::read(reader)?;
2299 let shutdown_script = Readable::read(reader)?;
2301 let keys = Readable::read(reader)?;
2302 // Technically this can fail and serialize fail a round-trip, but only for serialization of
2303 // barely-init'd ChannelMonitors that we can't do anything with.
2304 let outpoint = OutPoint {
2305 txid: Readable::read(reader)?,
2306 index: Readable::read(reader)?,
2308 let funding_info = (outpoint, Readable::read(reader)?);
2309 let current_remote_commitment_txid = Readable::read(reader)?;
2310 let prev_remote_commitment_txid = Readable::read(reader)?;
2312 let remote_tx_cache = Readable::read(reader)?;
2313 let funding_redeemscript = Readable::read(reader)?;
2314 let channel_value_satoshis = Readable::read(reader)?;
2316 let their_cur_revocation_points = {
2317 let first_idx = <U48 as Readable>::read(reader)?.0;
2321 let first_point = Readable::read(reader)?;
2322 let second_point_slice: [u8; 33] = Readable::read(reader)?;
2323 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
2324 Some((first_idx, first_point, None))
2326 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
2331 let on_local_tx_csv: u16 = Readable::read(reader)?;
2333 let commitment_secrets = Readable::read(reader)?;
2335 macro_rules! read_htlc_in_commitment {
2338 let offered: bool = Readable::read(reader)?;
2339 let amount_msat: u64 = Readable::read(reader)?;
2340 let cltv_expiry: u32 = Readable::read(reader)?;
2341 let payment_hash: PaymentHash = Readable::read(reader)?;
2342 let transaction_output_index: Option<u32> = Readable::read(reader)?;
2344 HTLCOutputInCommitment {
2345 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
2351 let remote_claimable_outpoints_len: u64 = Readable::read(reader)?;
2352 let mut remote_claimable_outpoints = HashMap::with_capacity(cmp::min(remote_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
2353 for _ in 0..remote_claimable_outpoints_len {
2354 let txid: Txid = Readable::read(reader)?;
2355 let htlcs_count: u64 = Readable::read(reader)?;
2356 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
2357 for _ in 0..htlcs_count {
2358 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
2360 if let Some(_) = remote_claimable_outpoints.insert(txid, htlcs) {
2361 return Err(DecodeError::InvalidValue);
2365 let remote_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
2366 let mut remote_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(remote_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
2367 for _ in 0..remote_commitment_txn_on_chain_len {
2368 let txid: Txid = Readable::read(reader)?;
2369 let commitment_number = <U48 as Readable>::read(reader)?.0;
2370 let outputs_count = <u64 as Readable>::read(reader)?;
2371 let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 8));
2372 for _ in 0..outputs_count {
2373 outputs.push(Readable::read(reader)?);
2375 if let Some(_) = remote_commitment_txn_on_chain.insert(txid, (commitment_number, outputs)) {
2376 return Err(DecodeError::InvalidValue);
2380 let remote_hash_commitment_number_len: u64 = Readable::read(reader)?;
2381 let mut remote_hash_commitment_number = HashMap::with_capacity(cmp::min(remote_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
2382 for _ in 0..remote_hash_commitment_number_len {
2383 let payment_hash: PaymentHash = Readable::read(reader)?;
2384 let commitment_number = <U48 as Readable>::read(reader)?.0;
2385 if let Some(_) = remote_hash_commitment_number.insert(payment_hash, commitment_number) {
2386 return Err(DecodeError::InvalidValue);
2390 macro_rules! read_local_tx {
2393 let txid = Readable::read(reader)?;
2394 let revocation_key = Readable::read(reader)?;
2395 let a_htlc_key = Readable::read(reader)?;
2396 let b_htlc_key = Readable::read(reader)?;
2397 let delayed_payment_key = Readable::read(reader)?;
2398 let per_commitment_point = Readable::read(reader)?;
2399 let feerate_per_kw: u32 = Readable::read(reader)?;
2401 let htlcs_len: u64 = Readable::read(reader)?;
2402 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_len as usize, MAX_ALLOC_SIZE / 128));
2403 for _ in 0..htlcs_len {
2404 let htlc = read_htlc_in_commitment!();
2405 let sigs = match <u8 as Readable>::read(reader)? {
2407 1 => Some(Readable::read(reader)?),
2408 _ => return Err(DecodeError::InvalidValue),
2410 htlcs.push((htlc, sigs, Readable::read(reader)?));
2415 revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, per_commitment_point, feerate_per_kw,
2422 let prev_local_signed_commitment_tx = match <u8 as Readable>::read(reader)? {
2425 Some(read_local_tx!())
2427 _ => return Err(DecodeError::InvalidValue),
2429 let current_local_commitment_tx = read_local_tx!();
2431 let current_remote_commitment_number = <U48 as Readable>::read(reader)?.0;
2432 let current_local_commitment_number = <U48 as Readable>::read(reader)?.0;
2434 let payment_preimages_len: u64 = Readable::read(reader)?;
2435 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
2436 for _ in 0..payment_preimages_len {
2437 let preimage: PaymentPreimage = Readable::read(reader)?;
2438 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2439 if let Some(_) = payment_preimages.insert(hash, preimage) {
2440 return Err(DecodeError::InvalidValue);
2444 let pending_monitor_events_len: u64 = Readable::read(reader)?;
2445 let mut pending_monitor_events = Vec::with_capacity(cmp::min(pending_monitor_events_len as usize, MAX_ALLOC_SIZE / (32 + 8*3)));
2446 for _ in 0..pending_monitor_events_len {
2447 let ev = match <u8 as Readable>::read(reader)? {
2448 0 => MonitorEvent::HTLCEvent(Readable::read(reader)?),
2449 1 => MonitorEvent::CommitmentTxBroadcasted(funding_info.0),
2450 _ => return Err(DecodeError::InvalidValue)
2452 pending_monitor_events.push(ev);
2455 let pending_events_len: u64 = Readable::read(reader)?;
2456 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Event>()));
2457 for _ in 0..pending_events_len {
2458 if let Some(event) = MaybeReadable::read(reader)? {
2459 pending_events.push(event);
2463 let last_block_hash: BlockHash = Readable::read(reader)?;
2465 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
2466 let mut onchain_events_waiting_threshold_conf = HashMap::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
2467 for _ in 0..waiting_threshold_conf_len {
2468 let height_target = Readable::read(reader)?;
2469 let events_len: u64 = Readable::read(reader)?;
2470 let mut events = Vec::with_capacity(cmp::min(events_len as usize, MAX_ALLOC_SIZE / 128));
2471 for _ in 0..events_len {
2472 let ev = match <u8 as Readable>::read(reader)? {
2474 let htlc_source = Readable::read(reader)?;
2475 let hash = Readable::read(reader)?;
2476 OnchainEvent::HTLCUpdate {
2477 htlc_update: (htlc_source, hash)
2481 let descriptor = Readable::read(reader)?;
2482 OnchainEvent::MaturingOutput {
2486 _ => return Err(DecodeError::InvalidValue),
2490 onchain_events_waiting_threshold_conf.insert(height_target, events);
2493 let outputs_to_watch_len: u64 = Readable::read(reader)?;
2494 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>>())));
2495 for _ in 0..outputs_to_watch_len {
2496 let txid = Readable::read(reader)?;
2497 let outputs_len: u64 = Readable::read(reader)?;
2498 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Script>()));
2499 for _ in 0..outputs_len {
2500 outputs.push(Readable::read(reader)?);
2502 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
2503 return Err(DecodeError::InvalidValue);
2506 let onchain_tx_handler = Readable::read(reader)?;
2508 let lockdown_from_offchain = Readable::read(reader)?;
2509 let local_tx_signed = Readable::read(reader)?;
2511 Ok((last_block_hash.clone(), ChannelMonitor {
2513 commitment_transaction_number_obscure_factor,
2516 broadcasted_local_revokable_script,
2517 remote_payment_script,
2522 current_remote_commitment_txid,
2523 prev_remote_commitment_txid,
2526 funding_redeemscript,
2527 channel_value_satoshis,
2528 their_cur_revocation_points,
2533 remote_claimable_outpoints,
2534 remote_commitment_txn_on_chain,
2535 remote_hash_commitment_number,
2537 prev_local_signed_commitment_tx,
2538 current_local_commitment_tx,
2539 current_remote_commitment_number,
2540 current_local_commitment_number,
2543 pending_monitor_events,
2546 onchain_events_waiting_threshold_conf,
2551 lockdown_from_offchain,
2555 secp_ctx: Secp256k1::new(),
2562 use bitcoin::blockdata::script::{Script, Builder};
2563 use bitcoin::blockdata::opcodes;
2564 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, SigHashType};
2565 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
2566 use bitcoin::util::bip143;
2567 use bitcoin::hashes::Hash;
2568 use bitcoin::hashes::sha256::Hash as Sha256;
2569 use bitcoin::hashes::hex::FromHex;
2570 use bitcoin::hash_types::Txid;
2572 use chain::transaction::OutPoint;
2573 use ln::channelmanager::{PaymentPreimage, PaymentHash};
2574 use ln::channelmonitor::ChannelMonitor;
2575 use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
2577 use ln::chan_utils::{HTLCOutputInCommitment, LocalCommitmentTransaction};
2578 use util::test_utils::TestLogger;
2579 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
2580 use bitcoin::secp256k1::Secp256k1;
2582 use chain::keysinterface::InMemoryChannelKeys;
2585 fn test_prune_preimages() {
2586 let secp_ctx = Secp256k1::new();
2587 let logger = Arc::new(TestLogger::new());
2589 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
2590 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2592 let mut preimages = Vec::new();
2595 let preimage = PaymentPreimage([i; 32]);
2596 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2597 preimages.push((preimage, hash));
2601 macro_rules! preimages_slice_to_htlc_outputs {
2602 ($preimages_slice: expr) => {
2604 let mut res = Vec::new();
2605 for (idx, preimage) in $preimages_slice.iter().enumerate() {
2606 res.push((HTLCOutputInCommitment {
2610 payment_hash: preimage.1.clone(),
2611 transaction_output_index: Some(idx as u32),
2618 macro_rules! preimages_to_local_htlcs {
2619 ($preimages_slice: expr) => {
2621 let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2622 let res: Vec<_> = inp.drain(..).map(|e| { (e.0, None, e.1) }).collect();
2628 macro_rules! test_preimages_exist {
2629 ($preimages_slice: expr, $monitor: expr) => {
2630 for preimage in $preimages_slice {
2631 assert!($monitor.payment_preimages.contains_key(&preimage.1));
2636 let keys = InMemoryChannelKeys::new(
2638 SecretKey::from_slice(&[41; 32]).unwrap(),
2639 SecretKey::from_slice(&[41; 32]).unwrap(),
2640 SecretKey::from_slice(&[41; 32]).unwrap(),
2641 SecretKey::from_slice(&[41; 32]).unwrap(),
2642 SecretKey::from_slice(&[41; 32]).unwrap(),
2648 // Prune with one old state and a local commitment tx holding a few overlaps with the
2650 let mut monitor = ChannelMonitor::new(keys,
2651 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()), 0, &Script::new(),
2652 (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
2653 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
2654 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
2655 10, Script::new(), 46, 0, LocalCommitmentTransaction::dummy());
2657 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..10])).unwrap();
2658 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
2659 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
2660 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
2661 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
2662 for &(ref preimage, ref hash) in preimages.iter() {
2663 monitor.provide_payment_preimage(hash, preimage);
2666 // Now provide a secret, pruning preimages 10-15
2667 let mut secret = [0; 32];
2668 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2669 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2670 assert_eq!(monitor.payment_preimages.len(), 15);
2671 test_preimages_exist!(&preimages[0..10], monitor);
2672 test_preimages_exist!(&preimages[15..20], monitor);
2674 // Now provide a further secret, pruning preimages 15-17
2675 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2676 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2677 assert_eq!(monitor.payment_preimages.len(), 13);
2678 test_preimages_exist!(&preimages[0..10], monitor);
2679 test_preimages_exist!(&preimages[17..20], monitor);
2681 // Now update local commitment tx info, pruning only element 18 as we still care about the
2682 // previous commitment tx's preimages too
2683 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..5])).unwrap();
2684 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2685 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2686 assert_eq!(monitor.payment_preimages.len(), 12);
2687 test_preimages_exist!(&preimages[0..10], monitor);
2688 test_preimages_exist!(&preimages[18..20], monitor);
2690 // But if we do it again, we'll prune 5-10
2691 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..3])).unwrap();
2692 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2693 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2694 assert_eq!(monitor.payment_preimages.len(), 5);
2695 test_preimages_exist!(&preimages[0..5], monitor);
2699 fn test_claim_txn_weight_computation() {
2700 // We test Claim txn weight, knowing that we want expected weigth and
2701 // not actual case to avoid sigs and time-lock delays hell variances.
2703 let secp_ctx = Secp256k1::new();
2704 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
2705 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
2706 let mut sum_actual_sigs = 0;
2708 macro_rules! sign_input {
2709 ($sighash_parts: expr, $input: expr, $idx: expr, $amount: expr, $input_type: expr, $sum_actual_sigs: expr) => {
2710 let htlc = HTLCOutputInCommitment {
2711 offered: if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::OfferedHTLC { true } else { false },
2713 cltv_expiry: 2 << 16,
2714 payment_hash: PaymentHash([1; 32]),
2715 transaction_output_index: Some($idx),
2717 let redeem_script = if *$input_type == InputDescriptors::RevokedOutput { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &pubkey, &pubkey, &pubkey) };
2718 let sighash = hash_to_message!(&$sighash_parts.sighash_all(&$input, &redeem_script, $amount)[..]);
2719 let sig = secp_ctx.sign(&sighash, &privkey);
2720 $input.witness.push(sig.serialize_der().to_vec());
2721 $input.witness[0].push(SigHashType::All as u8);
2722 sum_actual_sigs += $input.witness[0].len();
2723 if *$input_type == InputDescriptors::RevokedOutput {
2724 $input.witness.push(vec!(1));
2725 } else if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::RevokedReceivedHTLC {
2726 $input.witness.push(pubkey.clone().serialize().to_vec());
2727 } else if *$input_type == InputDescriptors::ReceivedHTLC {
2728 $input.witness.push(vec![0]);
2730 $input.witness.push(PaymentPreimage([1; 32]).0.to_vec());
2732 $input.witness.push(redeem_script.into_bytes());
2733 println!("witness[0] {}", $input.witness[0].len());
2734 println!("witness[1] {}", $input.witness[1].len());
2735 println!("witness[2] {}", $input.witness[2].len());
2739 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
2740 let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
2742 // Justice tx with 1 to_local, 2 revoked offered HTLCs, 1 revoked received HTLCs
2743 let mut claim_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2745 claim_tx.input.push(TxIn {
2746 previous_output: BitcoinOutPoint {
2750 script_sig: Script::new(),
2751 sequence: 0xfffffffd,
2752 witness: Vec::new(),
2755 claim_tx.output.push(TxOut {
2756 script_pubkey: script_pubkey.clone(),
2759 let base_weight = claim_tx.get_weight();
2760 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2761 let inputs_des = vec![InputDescriptors::RevokedOutput, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedReceivedHTLC];
2762 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2763 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2765 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));
2767 // Claim tx with 1 offered HTLCs, 3 received HTLCs
2768 claim_tx.input.clear();
2769 sum_actual_sigs = 0;
2771 claim_tx.input.push(TxIn {
2772 previous_output: BitcoinOutPoint {
2776 script_sig: Script::new(),
2777 sequence: 0xfffffffd,
2778 witness: Vec::new(),
2781 let base_weight = claim_tx.get_weight();
2782 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2783 let inputs_des = vec![InputDescriptors::OfferedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC];
2784 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2785 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2787 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));
2789 // Justice tx with 1 revoked HTLC-Success tx output
2790 claim_tx.input.clear();
2791 sum_actual_sigs = 0;
2792 claim_tx.input.push(TxIn {
2793 previous_output: BitcoinOutPoint {
2797 script_sig: Script::new(),
2798 sequence: 0xfffffffd,
2799 witness: Vec::new(),
2801 let base_weight = claim_tx.get_weight();
2802 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2803 let inputs_des = vec![InputDescriptors::RevokedOutput];
2804 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2805 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2807 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));
2810 // Further testing is done in the ChannelManager integration tests.