1 //! The logic to monitor for on-chain transactions and create the relevant claim responses lives
4 //! ChannelMonitor objects are generated by ChannelManager in response to relevant
5 //! messages/actions, and MUST be persisted to disk (and, preferably, remotely) before progress can
6 //! be made in responding to certain messages, see ManyChannelMonitor for more.
8 //! Note that ChannelMonitors are an important part of the lightning trust model and a copy of the
9 //! latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date
10 //! ChannelMonitors should do so). Thus, if you're building rust-lightning into an HSM or other
11 //! security-domain-separated system design, you should consider having multiple paths for
12 //! ChannelMonitors to get out of the HSM and onto monitoring devices.
14 use bitcoin::blockdata::block::BlockHeader;
15 use bitcoin::blockdata::transaction::{TxOut,Transaction};
16 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
17 use bitcoin::blockdata::script::{Script, Builder};
18 use bitcoin::blockdata::opcodes;
19 use bitcoin::consensus::encode;
20 use bitcoin::util::hash::BitcoinHash;
22 use bitcoin::hashes::Hash;
23 use bitcoin::hashes::sha256::Hash as Sha256;
24 use bitcoin::hash_types::{Txid, BlockHash, WPubkeyHash};
26 use bitcoin::secp256k1::{Secp256k1,Signature};
27 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
28 use bitcoin::secp256k1;
30 use ln::msgs::DecodeError;
32 use ln::chan_utils::{CounterpartyCommitmentSecrets, HTLCOutputInCommitment, LocalCommitmentTransaction, HTLCType};
33 use ln::channelmanager::{HTLCSource, PaymentPreimage, PaymentHash};
34 use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
36 use chain::chaininterface::{ChainListener, ChainWatchedUtil, BroadcasterInterface, FeeEstimator};
37 use chain::transaction::OutPoint;
38 use chain::keysinterface::{SpendableOutputDescriptor, ChannelKeys};
39 use util::logger::Logger;
40 use util::ser::{Readable, MaybeReadable, Writer, Writeable, U48};
41 use util::{byte_utils, events};
43 use std::collections::{HashMap, hash_map};
45 use std::{hash,cmp, mem};
48 /// An update generated by the underlying Channel itself which contains some new information the
49 /// ChannelMonitor should be made aware of.
50 #[cfg_attr(test, derive(PartialEq))]
53 pub struct ChannelMonitorUpdate {
54 pub(super) updates: Vec<ChannelMonitorUpdateStep>,
55 /// The sequence number of this update. Updates *must* be replayed in-order according to this
56 /// sequence number (and updates may panic if they are not). The update_id values are strictly
57 /// increasing and increase by one for each new update.
59 /// This sequence number is also used to track up to which points updates which returned
60 /// ChannelMonitorUpdateErr::TemporaryFailure have been applied to all copies of a given
61 /// ChannelMonitor when ChannelManager::channel_monitor_updated is called.
65 impl Writeable for ChannelMonitorUpdate {
66 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
67 self.update_id.write(w)?;
68 (self.updates.len() as u64).write(w)?;
69 for update_step in self.updates.iter() {
70 update_step.write(w)?;
75 impl Readable for ChannelMonitorUpdate {
76 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
77 let update_id: u64 = Readable::read(r)?;
78 let len: u64 = Readable::read(r)?;
79 let mut updates = Vec::with_capacity(cmp::min(len as usize, MAX_ALLOC_SIZE / ::std::mem::size_of::<ChannelMonitorUpdateStep>()));
81 updates.push(Readable::read(r)?);
83 Ok(Self { update_id, updates })
87 /// An error enum representing a failure to persist a channel monitor update.
89 pub enum ChannelMonitorUpdateErr {
90 /// Used to indicate a temporary failure (eg connection to a watchtower or remote backup of
91 /// our state failed, but is expected to succeed at some point in the future).
93 /// Such a failure will "freeze" a channel, preventing us from revoking old states or
94 /// submitting new commitment transactions to the remote party. Once the update(s) which failed
95 /// have been successfully applied, ChannelManager::channel_monitor_updated can be used to
96 /// restore the channel to an operational state.
98 /// Note that a given ChannelManager will *never* re-generate a given ChannelMonitorUpdate. If
99 /// you return a TemporaryFailure you must ensure that it is written to disk safely before
100 /// writing out the latest ChannelManager state.
102 /// Even when a channel has been "frozen" updates to the ChannelMonitor can continue to occur
103 /// (eg if an inbound HTLC which we forwarded was claimed upstream resulting in us attempting
104 /// to claim it on this channel) and those updates must be applied wherever they can be. At
105 /// least one such updated ChannelMonitor must be persisted otherwise PermanentFailure should
106 /// be returned to get things on-chain ASAP using only the in-memory copy. Obviously updates to
107 /// the channel which would invalidate previous ChannelMonitors are not made when a channel has
110 /// Note that even if updates made after TemporaryFailure succeed you must still call
111 /// channel_monitor_updated to ensure you have the latest monitor and re-enable normal channel
114 /// Note that the update being processed here will not be replayed for you when you call
115 /// ChannelManager::channel_monitor_updated, so you must store the update itself along
116 /// with the persisted ChannelMonitor on your own local disk prior to returning a
117 /// TemporaryFailure. You may, of course, employ a journaling approach, storing only the
118 /// ChannelMonitorUpdate on disk without updating the monitor itself, replaying the journal at
121 /// For deployments where a copy of ChannelMonitors and other local state are backed up in a
122 /// remote location (with local copies persisted immediately), it is anticipated that all
123 /// updates will return TemporaryFailure until the remote copies could be updated.
125 /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
126 /// different watchtower and cannot update with all watchtowers that were previously informed
127 /// of this channel). This will force-close the channel in question (which will generate one
128 /// final ChannelMonitorUpdate which must be delivered to at least one ChannelMonitor copy).
130 /// Should also be used to indicate a failure to update the local persisted copy of the channel
135 /// General Err type for ChannelMonitor actions. Generally, this implies that the data provided is
136 /// inconsistent with the ChannelMonitor being called. eg for ChannelMonitor::update_monitor this
137 /// means you tried to update a monitor for a different channel or the ChannelMonitorUpdate was
139 /// Contains a human-readable error message.
141 pub struct MonitorUpdateError(pub &'static str);
143 /// Simple structure send back by ManyChannelMonitor in case of HTLC detected onchain from a
144 /// forward channel and from which info are needed to update HTLC in a backward channel.
145 #[derive(Clone, PartialEq)]
146 pub struct HTLCUpdate {
147 pub(super) payment_hash: PaymentHash,
148 pub(super) payment_preimage: Option<PaymentPreimage>,
149 pub(super) source: HTLCSource
151 impl_writeable!(HTLCUpdate, 0, { payment_hash, payment_preimage, source });
153 /// A simple implementation of a ManyChannelMonitor and ChainListener. Can be used to create a
154 /// watchtower or watch our own channels.
156 /// Note that you must provide your own key by which to refer to channels.
158 /// If you're accepting remote monitors (ie are implementing a watchtower), you must verify that
159 /// users cannot overwrite a given channel by providing a duplicate key. ie you should probably
160 /// index by a PublicKey which is required to sign any updates.
162 /// If you're using this for local monitoring of your own channels, you probably want to use
163 /// `OutPoint` as the key, which will give you a ManyChannelMonitor implementation.
164 pub struct SimpleManyChannelMonitor<Key, ChanSigner: ChannelKeys, T: Deref, F: Deref, L: Deref>
165 where T::Target: BroadcasterInterface,
166 F::Target: FeeEstimator,
169 #[cfg(test)] // Used in ChannelManager tests to manipulate channels directly
170 pub monitors: Mutex<HashMap<Key, ChannelMonitor<ChanSigner>>>,
172 monitors: Mutex<HashMap<Key, ChannelMonitor<ChanSigner>>>,
173 watch_events: Mutex<WatchEventQueue>,
179 struct WatchEventQueue {
180 watched: ChainWatchedUtil,
181 events: Vec<chain::WatchEvent>,
184 impl WatchEventQueue {
187 watched: ChainWatchedUtil::new(),
192 fn watch_tx(&mut self, txid: &Txid, script_pubkey: &Script) {
193 if self.watched.register_tx(txid, script_pubkey) {
194 self.events.push(chain::WatchEvent::WatchTransaction {
196 script_pubkey: script_pubkey.clone()
201 fn watch_output(&mut self, outpoint: (&Txid, usize), script_pubkey: &Script) {
202 let (txid, index) = outpoint;
203 if self.watched.register_outpoint((*txid, index as u32), script_pubkey) {
204 self.events.push(chain::WatchEvent::WatchOutput {
209 script_pubkey: script_pubkey.clone(),
214 fn dequeue_events(&mut self) -> Vec<chain::WatchEvent> {
215 let mut pending_events = Vec::with_capacity(self.events.len());
216 pending_events.append(&mut self.events);
221 impl<Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys, T: Deref + Sync + Send, F: Deref + Sync + Send, L: Deref + Sync + Send>
222 ChainListener for SimpleManyChannelMonitor<Key, ChanSigner, T, F, L>
223 where T::Target: BroadcasterInterface,
224 F::Target: FeeEstimator,
227 fn block_connected(&self, header: &BlockHeader, txdata: &[(usize, &Transaction)], height: u32) {
228 let mut watch_events = self.watch_events.lock().unwrap();
229 let matched_txn: Vec<_> = txdata.iter().filter(|&&(_, tx)| watch_events.watched.does_match_tx(tx)).map(|e| *e).collect();
231 let mut monitors = self.monitors.lock().unwrap();
232 for monitor in monitors.values_mut() {
233 let txn_outputs = monitor.block_connected(header, &matched_txn, height, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
235 for (ref txid, ref outputs) in txn_outputs {
236 for (idx, output) in outputs.iter().enumerate() {
237 watch_events.watch_output((txid, idx), &output.script_pubkey);
244 fn block_disconnected(&self, header: &BlockHeader, disconnected_height: u32) {
245 let mut monitors = self.monitors.lock().unwrap();
246 for monitor in monitors.values_mut() {
247 monitor.block_disconnected(header, disconnected_height, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
252 impl<Key : Send + cmp::Eq + hash::Hash + 'static, ChanSigner: ChannelKeys, T: Deref, F: Deref, L: Deref> SimpleManyChannelMonitor<Key, ChanSigner, T, F, L>
253 where T::Target: BroadcasterInterface,
254 F::Target: FeeEstimator,
257 /// Creates a new object which can be used to monitor several channels given the chain
258 /// interface with which to register to receive notifications.
259 pub fn new(broadcaster: T, logger: L, feeest: F) -> SimpleManyChannelMonitor<Key, ChanSigner, T, F, L> {
260 let res = SimpleManyChannelMonitor {
261 monitors: Mutex::new(HashMap::new()),
262 watch_events: Mutex::new(WatchEventQueue::new()),
265 fee_estimator: feeest,
271 /// Adds or updates the monitor which monitors the channel referred to by the given key.
272 pub fn add_monitor_by_key(&self, key: Key, monitor: ChannelMonitor<ChanSigner>) -> Result<(), MonitorUpdateError> {
273 let mut watch_events = self.watch_events.lock().unwrap();
274 let mut monitors = self.monitors.lock().unwrap();
275 let entry = match monitors.entry(key) {
276 hash_map::Entry::Occupied(_) => return Err(MonitorUpdateError("Channel monitor for given key is already present")),
277 hash_map::Entry::Vacant(e) => e,
280 let funding_txo = monitor.get_funding_txo();
281 log_trace!(self.logger, "Got new Channel Monitor for channel {}", log_bytes!(funding_txo.0.to_channel_id()[..]));
282 watch_events.watch_tx(&funding_txo.0.txid, &funding_txo.1);
283 watch_events.watch_output((&funding_txo.0.txid, funding_txo.0.index as usize), &funding_txo.1);
284 for (txid, outputs) in monitor.get_outputs_to_watch().iter() {
285 for (idx, script) in outputs.iter().enumerate() {
286 watch_events.watch_output((txid, idx), script);
290 entry.insert(monitor);
294 /// Updates the monitor which monitors the channel referred to by the given key.
295 pub fn update_monitor_by_key(&self, key: Key, update: ChannelMonitorUpdate) -> Result<(), MonitorUpdateError> {
296 let mut monitors = self.monitors.lock().unwrap();
297 match monitors.get_mut(&key) {
298 Some(orig_monitor) => {
299 log_trace!(self.logger, "Updating Channel Monitor for channel {}", log_funding_info!(orig_monitor));
300 orig_monitor.update_monitor(update, &self.broadcaster, &self.logger)
302 None => Err(MonitorUpdateError("No such monitor registered"))
307 impl<ChanSigner: ChannelKeys, T: Deref + Sync + Send, F: Deref + Sync + Send, L: Deref + Sync + Send> ManyChannelMonitor for SimpleManyChannelMonitor<OutPoint, ChanSigner, T, F, L>
308 where T::Target: BroadcasterInterface,
309 F::Target: FeeEstimator,
312 type Keys = ChanSigner;
314 fn add_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor<ChanSigner>) -> Result<(), ChannelMonitorUpdateErr> {
315 match self.add_monitor_by_key(funding_txo, monitor) {
317 Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
321 fn update_monitor(&self, funding_txo: OutPoint, update: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr> {
322 match self.update_monitor_by_key(funding_txo, update) {
324 Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
328 fn get_and_clear_pending_htlcs_updated(&self) -> Vec<HTLCUpdate> {
329 let mut pending_htlcs_updated = Vec::new();
330 for chan in self.monitors.lock().unwrap().values_mut() {
331 pending_htlcs_updated.append(&mut chan.get_and_clear_pending_htlcs_updated());
333 pending_htlcs_updated
337 impl<Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys, T: Deref, F: Deref, L: Deref> events::EventsProvider for SimpleManyChannelMonitor<Key, ChanSigner, T, F, L>
338 where T::Target: BroadcasterInterface,
339 F::Target: FeeEstimator,
342 fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
343 let mut pending_events = Vec::new();
344 for chan in self.monitors.lock().unwrap().values_mut() {
345 pending_events.append(&mut chan.get_and_clear_pending_events());
351 impl<Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys, T: Deref, F: Deref, L: Deref> chain::WatchEventProvider for SimpleManyChannelMonitor<Key, ChanSigner, T, F, L>
352 where T::Target: BroadcasterInterface,
353 F::Target: FeeEstimator,
356 fn release_pending_watch_events(&self) -> Vec<chain::WatchEvent> {
357 self.watch_events.lock().unwrap().dequeue_events()
361 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
362 /// instead claiming it in its own individual transaction.
363 pub(crate) const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
364 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
365 /// HTLC-Success transaction.
366 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
367 /// transaction confirmed (and we use it in a few more, equivalent, places).
368 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 6;
369 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
370 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
371 /// copies of ChannelMonitors, including watchtowers). We could enforce the contract by failing
372 /// at CLTV expiration height but giving a grace period to our peer may be profitable for us if he
373 /// can provide an over-late preimage. Nevertheless, grace period has to be accounted in our
374 /// CLTV_EXPIRY_DELTA to be secure. Following this policy we may decrease the rate of channel failures
375 /// due to expiration but increase the cost of funds being locked longuer in case of failure.
376 /// This delay also cover a low-power peer being slow to process blocks and so being behind us on
377 /// accurate block height.
378 /// In case of onchain failure to be pass backward we may see the last block of ANTI_REORG_DELAY
379 /// with at worst this delay, so we are not only using this value as a mercy for them but also
380 /// us as a safeguard to delay with enough time.
381 pub(crate) const LATENCY_GRACE_PERIOD_BLOCKS: u32 = 3;
382 /// Number of blocks we wait on seeing a HTLC output being solved before we fail corresponding inbound
383 /// HTLCs. This prevents us from failing backwards and then getting a reorg resulting in us losing money.
384 /// We use also this delay to be sure we can remove our in-flight claim txn from bump candidates buffer.
385 /// It may cause spurrious generation of bumped claim txn but that's allright given the outpoint is already
386 /// solved by a previous claim tx. What we want to avoid is reorg evicting our claim tx and us not
387 /// keeping bumping another claim tx to solve the outpoint.
388 pub(crate) const ANTI_REORG_DELAY: u32 = 6;
389 /// Number of blocks before confirmation at which we fail back an un-relayed HTLC or at which we
390 /// refuse to accept a new HTLC.
392 /// This is used for a few separate purposes:
393 /// 1) if we've received an MPP HTLC to us and it expires within this many blocks and we are
394 /// waiting on additional parts (or waiting on the preimage for any HTLC from the user), we will
396 /// 2) if we receive an HTLC within this many blocks of its expiry (plus one to avoid a race
397 /// condition with the above), we will fail this HTLC without telling the user we received it,
398 /// 3) if we are waiting on a connection or a channel state update to send an HTLC to a peer, and
399 /// that HTLC expires within this many blocks, we will simply fail the HTLC instead.
401 /// (1) is all about protecting us - we need enough time to update the channel state before we hit
402 /// CLTV_CLAIM_BUFFER, at which point we'd go on chain to claim the HTLC with the preimage.
404 /// (2) is the same, but with an additional buffer to avoid accepting an HTLC which is immediately
405 /// in a race condition between the user connecting a block (which would fail it) and the user
406 /// providing us the preimage (which would claim it).
408 /// (3) is about our counterparty - we don't want to relay an HTLC to a counterparty when they may
409 /// end up force-closing the channel on us to claim it.
410 pub(crate) const HTLC_FAIL_BACK_BUFFER: u32 = CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS;
412 #[derive(Clone, PartialEq)]
413 struct LocalSignedTx {
414 /// txid of the transaction in tx, just used to make comparison faster
416 revocation_key: PublicKey,
417 a_htlc_key: PublicKey,
418 b_htlc_key: PublicKey,
419 delayed_payment_key: PublicKey,
420 per_commitment_point: PublicKey,
422 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
425 /// We use this to track remote commitment transactions and htlcs outputs and
426 /// use it to generate any justice or 2nd-stage preimage/timeout transactions.
428 struct RemoteCommitmentTransaction {
429 remote_delayed_payment_base_key: PublicKey,
430 remote_htlc_base_key: PublicKey,
431 on_remote_tx_csv: u16,
432 per_htlc: HashMap<Txid, Vec<HTLCOutputInCommitment>>
435 impl Writeable for RemoteCommitmentTransaction {
436 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
437 self.remote_delayed_payment_base_key.write(w)?;
438 self.remote_htlc_base_key.write(w)?;
439 w.write_all(&byte_utils::be16_to_array(self.on_remote_tx_csv))?;
440 w.write_all(&byte_utils::be64_to_array(self.per_htlc.len() as u64))?;
441 for (ref txid, ref htlcs) in self.per_htlc.iter() {
442 w.write_all(&txid[..])?;
443 w.write_all(&byte_utils::be64_to_array(htlcs.len() as u64))?;
444 for &ref htlc in htlcs.iter() {
451 impl Readable for RemoteCommitmentTransaction {
452 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
453 let remote_commitment_transaction = {
454 let remote_delayed_payment_base_key = Readable::read(r)?;
455 let remote_htlc_base_key = Readable::read(r)?;
456 let on_remote_tx_csv: u16 = Readable::read(r)?;
457 let per_htlc_len: u64 = Readable::read(r)?;
458 let mut per_htlc = HashMap::with_capacity(cmp::min(per_htlc_len as usize, MAX_ALLOC_SIZE / 64));
459 for _ in 0..per_htlc_len {
460 let txid: Txid = Readable::read(r)?;
461 let htlcs_count: u64 = Readable::read(r)?;
462 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
463 for _ in 0..htlcs_count {
464 let htlc = Readable::read(r)?;
467 if let Some(_) = per_htlc.insert(txid, htlcs) {
468 return Err(DecodeError::InvalidValue);
471 RemoteCommitmentTransaction {
472 remote_delayed_payment_base_key,
473 remote_htlc_base_key,
478 Ok(remote_commitment_transaction)
482 /// When ChannelMonitor discovers an onchain outpoint being a step of a channel and that it needs
483 /// to generate a tx to push channel state forward, we cache outpoint-solving tx material to build
484 /// a new bumped one in case of lenghty confirmation delay
485 #[derive(Clone, PartialEq)]
486 pub(crate) enum InputMaterial {
488 per_commitment_point: PublicKey,
489 remote_delayed_payment_base_key: PublicKey,
490 remote_htlc_base_key: PublicKey,
491 per_commitment_key: SecretKey,
492 input_descriptor: InputDescriptors,
494 htlc: Option<HTLCOutputInCommitment>,
495 on_remote_tx_csv: u16,
498 per_commitment_point: PublicKey,
499 remote_delayed_payment_base_key: PublicKey,
500 remote_htlc_base_key: PublicKey,
501 preimage: Option<PaymentPreimage>,
502 htlc: HTLCOutputInCommitment
505 preimage: Option<PaymentPreimage>,
509 funding_redeemscript: Script,
513 impl Writeable for InputMaterial {
514 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
516 &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} => {
517 writer.write_all(&[0; 1])?;
518 per_commitment_point.write(writer)?;
519 remote_delayed_payment_base_key.write(writer)?;
520 remote_htlc_base_key.write(writer)?;
521 writer.write_all(&per_commitment_key[..])?;
522 input_descriptor.write(writer)?;
523 writer.write_all(&byte_utils::be64_to_array(*amount))?;
525 on_remote_tx_csv.write(writer)?;
527 &InputMaterial::RemoteHTLC { ref per_commitment_point, ref remote_delayed_payment_base_key, ref remote_htlc_base_key, ref preimage, ref htlc} => {
528 writer.write_all(&[1; 1])?;
529 per_commitment_point.write(writer)?;
530 remote_delayed_payment_base_key.write(writer)?;
531 remote_htlc_base_key.write(writer)?;
532 preimage.write(writer)?;
535 &InputMaterial::LocalHTLC { ref preimage, ref amount } => {
536 writer.write_all(&[2; 1])?;
537 preimage.write(writer)?;
538 writer.write_all(&byte_utils::be64_to_array(*amount))?;
540 &InputMaterial::Funding { ref funding_redeemscript } => {
541 writer.write_all(&[3; 1])?;
542 funding_redeemscript.write(writer)?;
549 impl Readable for InputMaterial {
550 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
551 let input_material = match <u8 as Readable>::read(reader)? {
553 let per_commitment_point = Readable::read(reader)?;
554 let remote_delayed_payment_base_key = Readable::read(reader)?;
555 let remote_htlc_base_key = Readable::read(reader)?;
556 let per_commitment_key = Readable::read(reader)?;
557 let input_descriptor = Readable::read(reader)?;
558 let amount = Readable::read(reader)?;
559 let htlc = Readable::read(reader)?;
560 let on_remote_tx_csv = Readable::read(reader)?;
561 InputMaterial::Revoked {
562 per_commitment_point,
563 remote_delayed_payment_base_key,
564 remote_htlc_base_key,
573 let per_commitment_point = Readable::read(reader)?;
574 let remote_delayed_payment_base_key = Readable::read(reader)?;
575 let remote_htlc_base_key = Readable::read(reader)?;
576 let preimage = Readable::read(reader)?;
577 let htlc = Readable::read(reader)?;
578 InputMaterial::RemoteHTLC {
579 per_commitment_point,
580 remote_delayed_payment_base_key,
581 remote_htlc_base_key,
587 let preimage = Readable::read(reader)?;
588 let amount = Readable::read(reader)?;
589 InputMaterial::LocalHTLC {
595 InputMaterial::Funding {
596 funding_redeemscript: Readable::read(reader)?,
599 _ => return Err(DecodeError::InvalidValue),
605 /// ClaimRequest is a descriptor structure to communicate between detection
606 /// and reaction module. They are generated by ChannelMonitor while parsing
607 /// onchain txn leaked from a channel and handed over to OnchainTxHandler which
608 /// is responsible for opportunistic aggregation, selecting and enforcing
609 /// bumping logic, building and signing transactions.
610 pub(crate) struct ClaimRequest {
611 // Block height before which claiming is exclusive to one party,
612 // after reaching it, claiming may be contentious.
613 pub(crate) absolute_timelock: u32,
614 // Timeout tx must have nLocktime set which means aggregating multiple
615 // ones must take the higher nLocktime among them to satisfy all of them.
616 // Sadly it has few pitfalls, a) it takes longuer to get fund back b) CLTV_DELTA
617 // of a sooner-HTLC could be swallowed by the highest nLocktime of the HTLC set.
618 // Do simplify we mark them as non-aggregable.
619 pub(crate) aggregable: bool,
620 // Basic bitcoin outpoint (txid, vout)
621 pub(crate) outpoint: BitcoinOutPoint,
622 // Following outpoint type, set of data needed to generate transaction digest
623 // and satisfy witness program.
624 pub(crate) witness_data: InputMaterial
627 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
628 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
629 #[derive(Clone, PartialEq)]
631 /// HTLC output getting solved by a timeout, at maturation we pass upstream payment source information to solve
632 /// inbound HTLC in backward channel. Note, in case of preimage, we pass info to upstream without delay as we can
633 /// only win from it, so it's never an OnchainEvent
635 htlc_update: (HTLCSource, PaymentHash),
638 descriptor: SpendableOutputDescriptor,
642 const SERIALIZATION_VERSION: u8 = 1;
643 const MIN_SERIALIZATION_VERSION: u8 = 1;
645 #[cfg_attr(test, derive(PartialEq))]
647 pub(super) enum ChannelMonitorUpdateStep {
648 LatestLocalCommitmentTXInfo {
649 commitment_tx: LocalCommitmentTransaction,
650 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
652 LatestRemoteCommitmentTXInfo {
653 unsigned_commitment_tx: Transaction, // TODO: We should actually only need the txid here
654 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
655 commitment_number: u64,
656 their_revocation_point: PublicKey,
659 payment_preimage: PaymentPreimage,
665 /// Used to indicate that the no future updates will occur, and likely that the latest local
666 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
668 /// If set to false, we shouldn't broadcast the latest local commitment transaction as we
669 /// think we've fallen behind!
670 should_broadcast: bool,
674 impl Writeable for ChannelMonitorUpdateStep {
675 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
677 &ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { ref commitment_tx, ref htlc_outputs } => {
679 commitment_tx.write(w)?;
680 (htlc_outputs.len() as u64).write(w)?;
681 for &(ref output, ref signature, ref source) in htlc_outputs.iter() {
687 &ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { ref unsigned_commitment_tx, ref htlc_outputs, ref commitment_number, ref their_revocation_point } => {
689 unsigned_commitment_tx.write(w)?;
690 commitment_number.write(w)?;
691 their_revocation_point.write(w)?;
692 (htlc_outputs.len() as u64).write(w)?;
693 for &(ref output, ref source) in htlc_outputs.iter() {
695 source.as_ref().map(|b| b.as_ref()).write(w)?;
698 &ChannelMonitorUpdateStep::PaymentPreimage { ref payment_preimage } => {
700 payment_preimage.write(w)?;
702 &ChannelMonitorUpdateStep::CommitmentSecret { ref idx, ref secret } => {
707 &ChannelMonitorUpdateStep::ChannelForceClosed { ref should_broadcast } => {
709 should_broadcast.write(w)?;
715 impl Readable for ChannelMonitorUpdateStep {
716 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
717 match Readable::read(r)? {
719 Ok(ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo {
720 commitment_tx: Readable::read(r)?,
722 let len: u64 = Readable::read(r)?;
723 let mut res = Vec::new();
725 res.push((Readable::read(r)?, Readable::read(r)?, Readable::read(r)?));
732 Ok(ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo {
733 unsigned_commitment_tx: Readable::read(r)?,
734 commitment_number: Readable::read(r)?,
735 their_revocation_point: Readable::read(r)?,
737 let len: u64 = Readable::read(r)?;
738 let mut res = Vec::new();
740 res.push((Readable::read(r)?, <Option<HTLCSource> as Readable>::read(r)?.map(|o| Box::new(o))));
747 Ok(ChannelMonitorUpdateStep::PaymentPreimage {
748 payment_preimage: Readable::read(r)?,
752 Ok(ChannelMonitorUpdateStep::CommitmentSecret {
753 idx: Readable::read(r)?,
754 secret: Readable::read(r)?,
758 Ok(ChannelMonitorUpdateStep::ChannelForceClosed {
759 should_broadcast: Readable::read(r)?
762 _ => Err(DecodeError::InvalidValue),
767 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
768 /// on-chain transactions to ensure no loss of funds occurs.
770 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
771 /// information and are actively monitoring the chain.
773 /// Pending Events or updated HTLCs which have not yet been read out by
774 /// get_and_clear_pending_htlcs_updated or get_and_clear_pending_events are serialized to disk and
775 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
776 /// gotten are fully handled before re-serializing the new state.
777 pub struct ChannelMonitor<ChanSigner: ChannelKeys> {
778 latest_update_id: u64,
779 commitment_transaction_number_obscure_factor: u64,
781 destination_script: Script,
782 broadcasted_local_revokable_script: Option<(Script, PublicKey, PublicKey)>,
783 remote_payment_script: Script,
784 shutdown_script: Script,
787 funding_info: (OutPoint, Script),
788 current_remote_commitment_txid: Option<Txid>,
789 prev_remote_commitment_txid: Option<Txid>,
791 remote_tx_cache: RemoteCommitmentTransaction,
792 funding_redeemscript: Script,
793 channel_value_satoshis: u64,
794 // first is the idx of the first of the two revocation points
795 their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
797 on_local_tx_csv: u16,
799 commitment_secrets: CounterpartyCommitmentSecrets,
800 remote_claimable_outpoints: HashMap<Txid, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
801 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
802 /// Nor can we figure out their commitment numbers without the commitment transaction they are
803 /// spending. Thus, in order to claim them via revocation key, we track all the remote
804 /// commitment transactions which we find on-chain, mapping them to the commitment number which
805 /// can be used to derive the revocation key and claim the transactions.
806 remote_commitment_txn_on_chain: HashMap<Txid, (u64, Vec<Script>)>,
807 /// Cache used to make pruning of payment_preimages faster.
808 /// Maps payment_hash values to commitment numbers for remote transactions for non-revoked
809 /// remote transactions (ie should remain pretty small).
810 /// Serialized to disk but should generally not be sent to Watchtowers.
811 remote_hash_commitment_number: HashMap<PaymentHash, u64>,
813 // We store two local commitment transactions to avoid any race conditions where we may update
814 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
815 // various monitors for one channel being out of sync, and us broadcasting a local
816 // transaction for which we have deleted claim information on some watchtowers.
817 prev_local_signed_commitment_tx: Option<LocalSignedTx>,
818 current_local_commitment_tx: LocalSignedTx,
820 // Used just for ChannelManager to make sure it has the latest channel data during
822 current_remote_commitment_number: u64,
823 // Used just for ChannelManager to make sure it has the latest channel data during
825 current_local_commitment_number: u64,
827 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
829 pending_htlcs_updated: Vec<HTLCUpdate>,
830 pending_events: Vec<events::Event>,
832 // Used to track onchain events, i.e transactions parts of channels confirmed on chain, on which
833 // we have to take actions once they reach enough confs. Key is a block height timer, i.e we enforce
834 // actions when we receive a block with given height. Actions depend on OnchainEvent type.
835 onchain_events_waiting_threshold_conf: HashMap<u32, Vec<OnchainEvent>>,
837 // If we get serialized out and re-read, we need to make sure that the chain monitoring
838 // interface knows about the TXOs that we want to be notified of spends of. We could probably
839 // be smart and derive them from the above storage fields, but its much simpler and more
840 // Obviously Correct (tm) if we just keep track of them explicitly.
841 outputs_to_watch: HashMap<Txid, Vec<Script>>,
844 pub onchain_tx_handler: OnchainTxHandler<ChanSigner>,
846 onchain_tx_handler: OnchainTxHandler<ChanSigner>,
848 // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
849 // channel has been force-closed. After this is set, no further local commitment transaction
850 // updates may occur, and we panic!() if one is provided.
851 lockdown_from_offchain: bool,
853 // Set once we've signed a local commitment transaction and handed it over to our
854 // OnchainTxHandler. After this is set, no future updates to our local commitment transactions
855 // may occur, and we fail any such monitor updates.
856 local_tx_signed: bool,
858 // We simply modify last_block_hash in Channel's block_connected so that serialization is
859 // consistent but hopefully the users' copy handles block_connected in a consistent way.
860 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
861 // their last_block_hash from its state and not based on updated copies that didn't run through
862 // the full block_connected).
863 pub(crate) last_block_hash: BlockHash,
864 secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
867 /// Simple trait indicating ability to track a set of ChannelMonitors and multiplex events between
868 /// them. Generally should be implemented by keeping a local SimpleManyChannelMonitor and passing
869 /// events to it, while also taking any add/update_monitor events and passing them to some remote
872 /// In general, you must always have at least one local copy in memory, which must never fail to
873 /// update (as it is responsible for broadcasting the latest state in case the channel is closed),
874 /// and then persist it to various on-disk locations. If, for some reason, the in-memory copy fails
875 /// to update (eg out-of-memory or some other condition), you must immediately shut down without
876 /// taking any further action such as writing the current state to disk. This should likely be
877 /// accomplished via panic!() or abort().
879 /// Note that any updates to a channel's monitor *must* be applied to each instance of the
880 /// channel's monitor everywhere (including remote watchtowers) *before* this function returns. If
881 /// an update occurs and a remote watchtower is left with old state, it may broadcast transactions
882 /// which we have revoked, allowing our counterparty to claim all funds in the channel!
884 /// User needs to notify implementors of ManyChannelMonitor when a new block is connected or
885 /// disconnected using their `block_connected` and `block_disconnected` methods. However, rather
886 /// than calling these methods directly, the user should register implementors as listeners to the
887 /// BlockNotifier and call the BlockNotifier's `block_(dis)connected` methods, which will notify
888 /// all registered listeners in one go.
889 pub trait ManyChannelMonitor: Send + Sync {
890 /// The concrete type which signs for transactions and provides access to our channel public
892 type Keys: ChannelKeys;
894 /// Adds a monitor for the given `funding_txo`.
896 /// Implementations must ensure that `monitor` receives block_connected calls for blocks with
897 /// the funding transaction or any spends of it, as well as any spends of outputs returned by
898 /// get_outputs_to_watch. Not doing so may result in LOST FUNDS.
899 fn add_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor<Self::Keys>) -> Result<(), ChannelMonitorUpdateErr>;
901 /// Updates a monitor for the given `funding_txo`.
902 fn update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr>;
904 /// Used by ChannelManager to get list of HTLC resolved onchain and which needed to be updated
905 /// with success or failure.
907 /// You should probably just call through to
908 /// ChannelMonitor::get_and_clear_pending_htlcs_updated() for each ChannelMonitor and return
910 fn get_and_clear_pending_htlcs_updated(&self) -> Vec<HTLCUpdate>;
913 #[cfg(any(test, feature = "fuzztarget"))]
914 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
915 /// underlying object
916 impl<ChanSigner: ChannelKeys> PartialEq for ChannelMonitor<ChanSigner> {
917 fn eq(&self, other: &Self) -> bool {
918 if self.latest_update_id != other.latest_update_id ||
919 self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
920 self.destination_script != other.destination_script ||
921 self.broadcasted_local_revokable_script != other.broadcasted_local_revokable_script ||
922 self.remote_payment_script != other.remote_payment_script ||
923 self.keys.pubkeys() != other.keys.pubkeys() ||
924 self.funding_info != other.funding_info ||
925 self.current_remote_commitment_txid != other.current_remote_commitment_txid ||
926 self.prev_remote_commitment_txid != other.prev_remote_commitment_txid ||
927 self.remote_tx_cache != other.remote_tx_cache ||
928 self.funding_redeemscript != other.funding_redeemscript ||
929 self.channel_value_satoshis != other.channel_value_satoshis ||
930 self.their_cur_revocation_points != other.their_cur_revocation_points ||
931 self.on_local_tx_csv != other.on_local_tx_csv ||
932 self.commitment_secrets != other.commitment_secrets ||
933 self.remote_claimable_outpoints != other.remote_claimable_outpoints ||
934 self.remote_commitment_txn_on_chain != other.remote_commitment_txn_on_chain ||
935 self.remote_hash_commitment_number != other.remote_hash_commitment_number ||
936 self.prev_local_signed_commitment_tx != other.prev_local_signed_commitment_tx ||
937 self.current_remote_commitment_number != other.current_remote_commitment_number ||
938 self.current_local_commitment_number != other.current_local_commitment_number ||
939 self.current_local_commitment_tx != other.current_local_commitment_tx ||
940 self.payment_preimages != other.payment_preimages ||
941 self.pending_htlcs_updated != other.pending_htlcs_updated ||
942 self.pending_events.len() != other.pending_events.len() || // We trust events to round-trip properly
943 self.onchain_events_waiting_threshold_conf != other.onchain_events_waiting_threshold_conf ||
944 self.outputs_to_watch != other.outputs_to_watch ||
945 self.lockdown_from_offchain != other.lockdown_from_offchain ||
946 self.local_tx_signed != other.local_tx_signed
955 impl<ChanSigner: ChannelKeys + Writeable> ChannelMonitor<ChanSigner> {
956 /// Writes this monitor into the given writer, suitable for writing to disk.
958 /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
959 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
960 /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
961 /// returned block hash and the the current chain and then reconnecting blocks to get to the
962 /// best chain) upon deserializing the object!
963 pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
964 //TODO: We still write out all the serialization here manually instead of using the fancy
965 //serialization framework we have, we should migrate things over to it.
966 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
967 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
969 self.latest_update_id.write(writer)?;
971 // Set in initial Channel-object creation, so should always be set by now:
972 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
974 self.destination_script.write(writer)?;
975 if let Some(ref broadcasted_local_revokable_script) = self.broadcasted_local_revokable_script {
976 writer.write_all(&[0; 1])?;
977 broadcasted_local_revokable_script.0.write(writer)?;
978 broadcasted_local_revokable_script.1.write(writer)?;
979 broadcasted_local_revokable_script.2.write(writer)?;
981 writer.write_all(&[1; 1])?;
984 self.remote_payment_script.write(writer)?;
985 self.shutdown_script.write(writer)?;
987 self.keys.write(writer)?;
988 writer.write_all(&self.funding_info.0.txid[..])?;
989 writer.write_all(&byte_utils::be16_to_array(self.funding_info.0.index))?;
990 self.funding_info.1.write(writer)?;
991 self.current_remote_commitment_txid.write(writer)?;
992 self.prev_remote_commitment_txid.write(writer)?;
994 self.remote_tx_cache.write(writer)?;
995 self.funding_redeemscript.write(writer)?;
996 self.channel_value_satoshis.write(writer)?;
998 match self.their_cur_revocation_points {
999 Some((idx, pubkey, second_option)) => {
1000 writer.write_all(&byte_utils::be48_to_array(idx))?;
1001 writer.write_all(&pubkey.serialize())?;
1002 match second_option {
1003 Some(second_pubkey) => {
1004 writer.write_all(&second_pubkey.serialize())?;
1007 writer.write_all(&[0; 33])?;
1012 writer.write_all(&byte_utils::be48_to_array(0))?;
1016 writer.write_all(&byte_utils::be16_to_array(self.on_local_tx_csv))?;
1018 self.commitment_secrets.write(writer)?;
1020 macro_rules! serialize_htlc_in_commitment {
1021 ($htlc_output: expr) => {
1022 writer.write_all(&[$htlc_output.offered as u8; 1])?;
1023 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
1024 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
1025 writer.write_all(&$htlc_output.payment_hash.0[..])?;
1026 $htlc_output.transaction_output_index.write(writer)?;
1030 writer.write_all(&byte_utils::be64_to_array(self.remote_claimable_outpoints.len() as u64))?;
1031 for (ref txid, ref htlc_infos) in self.remote_claimable_outpoints.iter() {
1032 writer.write_all(&txid[..])?;
1033 writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
1034 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
1035 serialize_htlc_in_commitment!(htlc_output);
1036 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
1040 writer.write_all(&byte_utils::be64_to_array(self.remote_commitment_txn_on_chain.len() as u64))?;
1041 for (ref txid, &(commitment_number, ref txouts)) in self.remote_commitment_txn_on_chain.iter() {
1042 writer.write_all(&txid[..])?;
1043 writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
1044 (txouts.len() as u64).write(writer)?;
1045 for script in txouts.iter() {
1046 script.write(writer)?;
1050 writer.write_all(&byte_utils::be64_to_array(self.remote_hash_commitment_number.len() as u64))?;
1051 for (ref payment_hash, commitment_number) in self.remote_hash_commitment_number.iter() {
1052 writer.write_all(&payment_hash.0[..])?;
1053 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
1056 macro_rules! serialize_local_tx {
1057 ($local_tx: expr) => {
1058 $local_tx.txid.write(writer)?;
1059 writer.write_all(&$local_tx.revocation_key.serialize())?;
1060 writer.write_all(&$local_tx.a_htlc_key.serialize())?;
1061 writer.write_all(&$local_tx.b_htlc_key.serialize())?;
1062 writer.write_all(&$local_tx.delayed_payment_key.serialize())?;
1063 writer.write_all(&$local_tx.per_commitment_point.serialize())?;
1065 writer.write_all(&byte_utils::be32_to_array($local_tx.feerate_per_kw))?;
1066 writer.write_all(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64))?;
1067 for &(ref htlc_output, ref sig, ref htlc_source) in $local_tx.htlc_outputs.iter() {
1068 serialize_htlc_in_commitment!(htlc_output);
1069 if let &Some(ref their_sig) = sig {
1071 writer.write_all(&their_sig.serialize_compact())?;
1075 htlc_source.write(writer)?;
1080 if let Some(ref prev_local_tx) = self.prev_local_signed_commitment_tx {
1081 writer.write_all(&[1; 1])?;
1082 serialize_local_tx!(prev_local_tx);
1084 writer.write_all(&[0; 1])?;
1087 serialize_local_tx!(self.current_local_commitment_tx);
1089 writer.write_all(&byte_utils::be48_to_array(self.current_remote_commitment_number))?;
1090 writer.write_all(&byte_utils::be48_to_array(self.current_local_commitment_number))?;
1092 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
1093 for payment_preimage in self.payment_preimages.values() {
1094 writer.write_all(&payment_preimage.0[..])?;
1097 writer.write_all(&byte_utils::be64_to_array(self.pending_htlcs_updated.len() as u64))?;
1098 for data in self.pending_htlcs_updated.iter() {
1099 data.write(writer)?;
1102 writer.write_all(&byte_utils::be64_to_array(self.pending_events.len() as u64))?;
1103 for event in self.pending_events.iter() {
1104 event.write(writer)?;
1107 self.last_block_hash.write(writer)?;
1109 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_waiting_threshold_conf.len() as u64))?;
1110 for (ref target, ref events) in self.onchain_events_waiting_threshold_conf.iter() {
1111 writer.write_all(&byte_utils::be32_to_array(**target))?;
1112 writer.write_all(&byte_utils::be64_to_array(events.len() as u64))?;
1113 for ev in events.iter() {
1115 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1117 htlc_update.0.write(writer)?;
1118 htlc_update.1.write(writer)?;
1120 OnchainEvent::MaturingOutput { ref descriptor } => {
1122 descriptor.write(writer)?;
1128 (self.outputs_to_watch.len() as u64).write(writer)?;
1129 for (txid, output_scripts) in self.outputs_to_watch.iter() {
1130 txid.write(writer)?;
1131 (output_scripts.len() as u64).write(writer)?;
1132 for script in output_scripts.iter() {
1133 script.write(writer)?;
1136 self.onchain_tx_handler.write(writer)?;
1138 self.lockdown_from_offchain.write(writer)?;
1139 self.local_tx_signed.write(writer)?;
1145 impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
1146 pub(super) fn new(keys: ChanSigner, shutdown_pubkey: &PublicKey,
1147 on_remote_tx_csv: u16, destination_script: &Script, funding_info: (OutPoint, Script),
1148 remote_htlc_base_key: &PublicKey, remote_delayed_payment_base_key: &PublicKey,
1149 on_local_tx_csv: u16, funding_redeemscript: Script, channel_value_satoshis: u64,
1150 commitment_transaction_number_obscure_factor: u64,
1151 initial_local_commitment_tx: LocalCommitmentTransaction) -> ChannelMonitor<ChanSigner> {
1153 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
1154 let our_channel_close_key_hash = WPubkeyHash::hash(&shutdown_pubkey.serialize());
1155 let shutdown_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
1156 let payment_key_hash = WPubkeyHash::hash(&keys.pubkeys().payment_point.serialize());
1157 let remote_payment_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_key_hash[..]).into_script();
1159 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() };
1161 let mut onchain_tx_handler = OnchainTxHandler::new(destination_script.clone(), keys.clone(), on_local_tx_csv);
1163 let local_tx_sequence = initial_local_commitment_tx.unsigned_tx.input[0].sequence as u64;
1164 let local_tx_locktime = initial_local_commitment_tx.unsigned_tx.lock_time as u64;
1165 let local_commitment_tx = LocalSignedTx {
1166 txid: initial_local_commitment_tx.txid(),
1167 revocation_key: initial_local_commitment_tx.local_keys.revocation_key,
1168 a_htlc_key: initial_local_commitment_tx.local_keys.a_htlc_key,
1169 b_htlc_key: initial_local_commitment_tx.local_keys.b_htlc_key,
1170 delayed_payment_key: initial_local_commitment_tx.local_keys.a_delayed_payment_key,
1171 per_commitment_point: initial_local_commitment_tx.local_keys.per_commitment_point,
1172 feerate_per_kw: initial_local_commitment_tx.feerate_per_kw,
1173 htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
1175 // Returning a monitor error before updating tracking points means in case of using
1176 // a concurrent watchtower implementation for same channel, if this one doesn't
1177 // reject update as we do, you MAY have the latest local valid commitment tx onchain
1178 // for which you want to spend outputs. We're NOT robust again this scenario right
1179 // now but we should consider it later.
1180 onchain_tx_handler.provide_latest_local_tx(initial_local_commitment_tx).unwrap();
1183 latest_update_id: 0,
1184 commitment_transaction_number_obscure_factor,
1186 destination_script: destination_script.clone(),
1187 broadcasted_local_revokable_script: None,
1188 remote_payment_script,
1193 current_remote_commitment_txid: None,
1194 prev_remote_commitment_txid: None,
1197 funding_redeemscript,
1198 channel_value_satoshis: channel_value_satoshis,
1199 their_cur_revocation_points: None,
1203 commitment_secrets: CounterpartyCommitmentSecrets::new(),
1204 remote_claimable_outpoints: HashMap::new(),
1205 remote_commitment_txn_on_chain: HashMap::new(),
1206 remote_hash_commitment_number: HashMap::new(),
1208 prev_local_signed_commitment_tx: None,
1209 current_local_commitment_tx: local_commitment_tx,
1210 current_remote_commitment_number: 1 << 48,
1211 current_local_commitment_number: 0xffff_ffff_ffff - ((((local_tx_sequence & 0xffffff) << 3*8) | (local_tx_locktime as u64 & 0xffffff)) ^ commitment_transaction_number_obscure_factor),
1213 payment_preimages: HashMap::new(),
1214 pending_htlcs_updated: Vec::new(),
1215 pending_events: Vec::new(),
1217 onchain_events_waiting_threshold_conf: HashMap::new(),
1218 outputs_to_watch: HashMap::new(),
1222 lockdown_from_offchain: false,
1223 local_tx_signed: false,
1225 last_block_hash: Default::default(),
1226 secp_ctx: Secp256k1::new(),
1230 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
1231 /// needed by local commitment transactions HTCLs nor by remote ones. Unless we haven't already seen remote
1232 /// commitment transaction's secret, they are de facto pruned (we can use revocation key).
1233 pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
1234 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
1235 return Err(MonitorUpdateError("Previous secret did not match new one"));
1238 // Prune HTLCs from the previous remote commitment tx so we don't generate failure/fulfill
1239 // events for now-revoked/fulfilled HTLCs.
1240 if let Some(txid) = self.prev_remote_commitment_txid.take() {
1241 for &mut (_, ref mut source) in self.remote_claimable_outpoints.get_mut(&txid).unwrap() {
1246 if !self.payment_preimages.is_empty() {
1247 let cur_local_signed_commitment_tx = &self.current_local_commitment_tx;
1248 let prev_local_signed_commitment_tx = self.prev_local_signed_commitment_tx.as_ref();
1249 let min_idx = self.get_min_seen_secret();
1250 let remote_hash_commitment_number = &mut self.remote_hash_commitment_number;
1252 self.payment_preimages.retain(|&k, _| {
1253 for &(ref htlc, _, _) in cur_local_signed_commitment_tx.htlc_outputs.iter() {
1254 if k == htlc.payment_hash {
1258 if let Some(prev_local_commitment_tx) = prev_local_signed_commitment_tx {
1259 for &(ref htlc, _, _) in prev_local_commitment_tx.htlc_outputs.iter() {
1260 if k == htlc.payment_hash {
1265 let contains = if let Some(cn) = remote_hash_commitment_number.get(&k) {
1272 remote_hash_commitment_number.remove(&k);
1281 /// Informs this monitor of the latest remote (ie non-broadcastable) commitment transaction.
1282 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
1283 /// possibly future revocation/preimage information) to claim outputs where possible.
1284 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
1285 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 {
1286 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
1287 // so that a remote monitor doesn't learn anything unless there is a malicious close.
1288 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
1290 for &(ref htlc, _) in &htlc_outputs {
1291 self.remote_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
1294 let new_txid = unsigned_commitment_tx.txid();
1295 log_trace!(logger, "Tracking new remote commitment transaction with txid {} at commitment number {} with {} HTLC outputs", new_txid, commitment_number, htlc_outputs.len());
1296 log_trace!(logger, "New potential remote commitment transaction: {}", encode::serialize_hex(unsigned_commitment_tx));
1297 self.prev_remote_commitment_txid = self.current_remote_commitment_txid.take();
1298 self.current_remote_commitment_txid = Some(new_txid);
1299 self.remote_claimable_outpoints.insert(new_txid, htlc_outputs.clone());
1300 self.current_remote_commitment_number = commitment_number;
1301 //TODO: Merge this into the other per-remote-transaction output storage stuff
1302 match self.their_cur_revocation_points {
1303 Some(old_points) => {
1304 if old_points.0 == commitment_number + 1 {
1305 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
1306 } else if old_points.0 == commitment_number + 2 {
1307 if let Some(old_second_point) = old_points.2 {
1308 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
1310 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1313 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1317 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1320 let mut htlcs = Vec::with_capacity(htlc_outputs.len());
1321 for htlc in htlc_outputs {
1322 if htlc.0.transaction_output_index.is_some() {
1326 self.remote_tx_cache.per_htlc.insert(new_txid, htlcs);
1329 /// Informs this monitor of the latest local (ie broadcastable) commitment transaction. The
1330 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
1331 /// is important that any clones of this channel monitor (including remote clones) by kept
1332 /// up-to-date as our local commitment transaction is updated.
1333 /// Panics if set_on_local_tx_csv has never been called.
1334 pub(super) fn provide_latest_local_commitment_tx_info(&mut self, commitment_tx: LocalCommitmentTransaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), MonitorUpdateError> {
1335 if self.local_tx_signed {
1336 return Err(MonitorUpdateError("A local commitment tx has already been signed, no new local commitment txn can be sent to our counterparty"));
1338 let txid = commitment_tx.txid();
1339 let sequence = commitment_tx.unsigned_tx.input[0].sequence as u64;
1340 let locktime = commitment_tx.unsigned_tx.lock_time as u64;
1341 let mut new_local_commitment_tx = LocalSignedTx {
1343 revocation_key: commitment_tx.local_keys.revocation_key,
1344 a_htlc_key: commitment_tx.local_keys.a_htlc_key,
1345 b_htlc_key: commitment_tx.local_keys.b_htlc_key,
1346 delayed_payment_key: commitment_tx.local_keys.a_delayed_payment_key,
1347 per_commitment_point: commitment_tx.local_keys.per_commitment_point,
1348 feerate_per_kw: commitment_tx.feerate_per_kw,
1349 htlc_outputs: htlc_outputs,
1351 // Returning a monitor error before updating tracking points means in case of using
1352 // a concurrent watchtower implementation for same channel, if this one doesn't
1353 // reject update as we do, you MAY have the latest local valid commitment tx onchain
1354 // for which you want to spend outputs. We're NOT robust again this scenario right
1355 // now but we should consider it later.
1356 if let Err(_) = self.onchain_tx_handler.provide_latest_local_tx(commitment_tx) {
1357 return Err(MonitorUpdateError("Local commitment signed has already been signed, no further update of LOCAL commitment transaction is allowed"));
1359 self.current_local_commitment_number = 0xffff_ffff_ffff - ((((sequence & 0xffffff) << 3*8) | (locktime as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
1360 mem::swap(&mut new_local_commitment_tx, &mut self.current_local_commitment_tx);
1361 self.prev_local_signed_commitment_tx = Some(new_local_commitment_tx);
1365 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
1366 /// commitment_tx_infos which contain the payment hash have been revoked.
1367 pub(super) fn provide_payment_preimage(&mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage) {
1368 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
1371 pub(super) fn broadcast_latest_local_commitment_txn<B: Deref, L: Deref>(&mut self, broadcaster: &B, logger: &L)
1372 where B::Target: BroadcasterInterface,
1375 for tx in self.get_latest_local_commitment_txn(logger).iter() {
1376 broadcaster.broadcast_transaction(tx);
1380 /// Used in Channel to cheat wrt the update_ids since it plays games, will be removed soon!
1381 pub(super) fn update_monitor_ooo<L: Deref>(&mut self, mut updates: ChannelMonitorUpdate, logger: &L) -> Result<(), MonitorUpdateError> where L::Target: Logger {
1382 for update in updates.updates.drain(..) {
1384 ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { commitment_tx, htlc_outputs } => {
1385 if self.lockdown_from_offchain { panic!(); }
1386 self.provide_latest_local_commitment_tx_info(commitment_tx, htlc_outputs)?
1388 ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
1389 self.provide_latest_remote_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point, logger),
1390 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
1391 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
1392 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
1393 self.provide_secret(idx, secret)?,
1394 ChannelMonitorUpdateStep::ChannelForceClosed { .. } => {},
1397 self.latest_update_id = updates.update_id;
1401 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
1404 /// panics if the given update is not the next update by update_id.
1405 pub fn update_monitor<B: Deref, L: Deref>(&mut self, mut updates: ChannelMonitorUpdate, broadcaster: &B, logger: &L) -> Result<(), MonitorUpdateError>
1406 where B::Target: BroadcasterInterface,
1409 if self.latest_update_id + 1 != updates.update_id {
1410 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
1412 for update in updates.updates.drain(..) {
1414 ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { commitment_tx, htlc_outputs } => {
1415 if self.lockdown_from_offchain { panic!(); }
1416 self.provide_latest_local_commitment_tx_info(commitment_tx, htlc_outputs)?
1418 ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
1419 self.provide_latest_remote_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point, logger),
1420 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
1421 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
1422 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
1423 self.provide_secret(idx, secret)?,
1424 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
1425 self.lockdown_from_offchain = true;
1426 if should_broadcast {
1427 self.broadcast_latest_local_commitment_txn(broadcaster, logger);
1429 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");
1434 self.latest_update_id = updates.update_id;
1438 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
1440 pub fn get_latest_update_id(&self) -> u64 {
1441 self.latest_update_id
1444 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
1445 pub fn get_funding_txo(&self) -> &(OutPoint, Script) {
1449 /// Gets a list of txids, with their output scripts (in the order they appear in the
1450 /// transaction), which we must learn about spends of via block_connected().
1451 pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<Script>> {
1452 &self.outputs_to_watch
1455 /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
1456 /// Generally useful when deserializing as during normal operation the return values of
1457 /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
1458 /// that the get_funding_txo outpoint and transaction must also be monitored for!).
1459 pub fn get_monitored_outpoints(&self) -> Vec<(Txid, u32, &Script)> {
1460 let mut res = Vec::with_capacity(self.remote_commitment_txn_on_chain.len() * 2);
1461 for (ref txid, &(_, ref outputs)) in self.remote_commitment_txn_on_chain.iter() {
1462 for (idx, output) in outputs.iter().enumerate() {
1463 res.push(((*txid).clone(), idx as u32, output));
1469 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1470 /// ChannelManager via ManyChannelMonitor::get_and_clear_pending_htlcs_updated().
1471 pub fn get_and_clear_pending_htlcs_updated(&mut self) -> Vec<HTLCUpdate> {
1472 let mut ret = Vec::new();
1473 mem::swap(&mut ret, &mut self.pending_htlcs_updated);
1477 /// Gets the list of pending events which were generated by previous actions, clearing the list
1480 /// This is called by ManyChannelMonitor::get_and_clear_pending_events() and is equivalent to
1481 /// EventsProvider::get_and_clear_pending_events() except that it requires &mut self as we do
1482 /// no internal locking in ChannelMonitors.
1483 pub fn get_and_clear_pending_events(&mut self) -> Vec<events::Event> {
1484 let mut ret = Vec::new();
1485 mem::swap(&mut ret, &mut self.pending_events);
1489 /// Can only fail if idx is < get_min_seen_secret
1490 pub(super) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
1491 self.commitment_secrets.get_secret(idx)
1494 pub(super) fn get_min_seen_secret(&self) -> u64 {
1495 self.commitment_secrets.get_min_seen_secret()
1498 pub(super) fn get_cur_remote_commitment_number(&self) -> u64 {
1499 self.current_remote_commitment_number
1502 pub(super) fn get_cur_local_commitment_number(&self) -> u64 {
1503 self.current_local_commitment_number
1506 /// Attempts to claim a remote commitment transaction's outputs using the revocation key and
1507 /// data in remote_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
1508 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
1509 /// HTLC-Success/HTLC-Timeout transactions.
1510 /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
1511 /// revoked remote commitment tx
1512 fn check_spend_remote_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) where L::Target: Logger {
1513 // Most secp and related errors trying to create keys means we have no hope of constructing
1514 // a spend transaction...so we return no transactions to broadcast
1515 let mut claimable_outpoints = Vec::new();
1516 let mut watch_outputs = Vec::new();
1518 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1519 let per_commitment_option = self.remote_claimable_outpoints.get(&commitment_txid);
1521 macro_rules! ignore_error {
1522 ( $thing : expr ) => {
1525 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs))
1530 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);
1531 if commitment_number >= self.get_min_seen_secret() {
1532 let secret = self.get_secret(commitment_number).unwrap();
1533 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1534 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1535 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.keys.pubkeys().revocation_basepoint));
1536 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));
1538 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.remote_tx_cache.on_remote_tx_csv, &delayed_key);
1539 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1541 // First, process non-htlc outputs (to_local & to_remote)
1542 for (idx, outp) in tx.output.iter().enumerate() {
1543 if outp.script_pubkey == revokeable_p2wsh {
1544 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};
1545 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});
1549 // Then, try to find revoked htlc outputs
1550 if let Some(ref per_commitment_data) = per_commitment_option {
1551 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1552 if let Some(transaction_output_index) = htlc.transaction_output_index {
1553 if transaction_output_index as usize >= tx.output.len() ||
1554 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1555 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1557 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};
1558 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable: true, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1563 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
1564 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
1565 // We're definitely a remote commitment transaction!
1566 log_trace!(logger, "Got broadcast of revoked remote commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
1567 watch_outputs.append(&mut tx.output.clone());
1568 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1570 macro_rules! check_htlc_fails {
1571 ($txid: expr, $commitment_tx: expr) => {
1572 if let Some(ref outpoints) = self.remote_claimable_outpoints.get($txid) {
1573 for &(ref htlc, ref source_option) in outpoints.iter() {
1574 if let &Some(ref source) = source_option {
1575 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), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1576 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1577 hash_map::Entry::Occupied(mut entry) => {
1578 let e = entry.get_mut();
1579 e.retain(|ref event| {
1581 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1582 return htlc_update.0 != **source
1587 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1589 hash_map::Entry::Vacant(entry) => {
1590 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1598 if let Some(ref txid) = self.current_remote_commitment_txid {
1599 check_htlc_fails!(txid, "current");
1601 if let Some(ref txid) = self.prev_remote_commitment_txid {
1602 check_htlc_fails!(txid, "remote");
1604 // No need to check local commitment txn, symmetric HTLCSource must be present as per-htlc data on remote commitment tx
1606 } else if let Some(per_commitment_data) = per_commitment_option {
1607 // While this isn't useful yet, there is a potential race where if a counterparty
1608 // revokes a state at the same time as the commitment transaction for that state is
1609 // confirmed, and the watchtower receives the block before the user, the user could
1610 // upload a new ChannelMonitor with the revocation secret but the watchtower has
1611 // already processed the block, resulting in the remote_commitment_txn_on_chain entry
1612 // not being generated by the above conditional. Thus, to be safe, we go ahead and
1614 watch_outputs.append(&mut tx.output.clone());
1615 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1617 log_trace!(logger, "Got broadcast of non-revoked remote commitment transaction {}", commitment_txid);
1619 macro_rules! check_htlc_fails {
1620 ($txid: expr, $commitment_tx: expr, $id: tt) => {
1621 if let Some(ref latest_outpoints) = self.remote_claimable_outpoints.get($txid) {
1622 $id: for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1623 if let &Some(ref source) = source_option {
1624 // Check if the HTLC is present in the commitment transaction that was
1625 // broadcast, but not if it was below the dust limit, which we should
1626 // fail backwards immediately as there is no way for us to learn the
1627 // payment_preimage.
1628 // Note that if the dust limit were allowed to change between
1629 // commitment transactions we'd want to be check whether *any*
1630 // broadcastable commitment transaction has the HTLC in it, but it
1631 // cannot currently change after channel initialization, so we don't
1633 for &(ref broadcast_htlc, ref broadcast_source) in per_commitment_data.iter() {
1634 if broadcast_htlc.transaction_output_index.is_some() && Some(source) == broadcast_source.as_ref() {
1638 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);
1639 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1640 hash_map::Entry::Occupied(mut entry) => {
1641 let e = entry.get_mut();
1642 e.retain(|ref event| {
1644 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1645 return htlc_update.0 != **source
1650 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1652 hash_map::Entry::Vacant(entry) => {
1653 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1661 if let Some(ref txid) = self.current_remote_commitment_txid {
1662 check_htlc_fails!(txid, "current", 'current_loop);
1664 if let Some(ref txid) = self.prev_remote_commitment_txid {
1665 check_htlc_fails!(txid, "previous", 'prev_loop);
1668 if let Some(revocation_points) = self.their_cur_revocation_points {
1669 let revocation_point_option =
1670 if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1671 else if let Some(point) = revocation_points.2.as_ref() {
1672 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1674 if let Some(revocation_point) = revocation_point_option {
1675 self.remote_payment_script = {
1676 // Note that the Network here is ignored as we immediately drop the address for the
1677 // script_pubkey version
1678 let payment_hash160 = WPubkeyHash::hash(&self.keys.pubkeys().payment_point.serialize());
1679 Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_hash160[..]).into_script()
1682 // Then, try to find htlc outputs
1683 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1684 if let Some(transaction_output_index) = htlc.transaction_output_index {
1685 if transaction_output_index as usize >= tx.output.len() ||
1686 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1687 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1689 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
1690 let aggregable = if !htlc.offered { false } else { true };
1691 if preimage.is_some() || !htlc.offered {
1692 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() };
1693 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1700 (claimable_outpoints, (commitment_txid, watch_outputs))
1703 /// Attempts to claim a remote HTLC-Success/HTLC-Timeout's outputs using the revocation key
1704 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 {
1705 let htlc_txid = tx.txid();
1706 if tx.input.len() != 1 || tx.output.len() != 1 || tx.input[0].witness.len() != 5 {
1707 return (Vec::new(), None)
1710 macro_rules! ignore_error {
1711 ( $thing : expr ) => {
1714 Err(_) => return (Vec::new(), None)
1719 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
1720 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1721 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1723 log_trace!(logger, "Remote HTLC broadcast {}:{}", htlc_txid, 0);
1724 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 };
1725 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 });
1726 (claimable_outpoints, Some((htlc_txid, tx.output.clone())))
1729 fn broadcast_by_local_state(&self, commitment_tx: &Transaction, local_tx: &LocalSignedTx) -> (Vec<ClaimRequest>, Vec<TxOut>, Option<(Script, PublicKey, PublicKey)>) {
1730 let mut claim_requests = Vec::with_capacity(local_tx.htlc_outputs.len());
1731 let mut watch_outputs = Vec::with_capacity(local_tx.htlc_outputs.len());
1733 let redeemscript = chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.on_local_tx_csv, &local_tx.delayed_payment_key);
1734 let broadcasted_local_revokable_script = Some((redeemscript.to_v0_p2wsh(), local_tx.per_commitment_point.clone(), local_tx.revocation_key.clone()));
1736 for &(ref htlc, _, _) in local_tx.htlc_outputs.iter() {
1737 if let Some(transaction_output_index) = htlc.transaction_output_index {
1738 claim_requests.push(ClaimRequest { absolute_timelock: ::std::u32::MAX, aggregable: false, outpoint: BitcoinOutPoint { txid: local_tx.txid, vout: transaction_output_index as u32 },
1739 witness_data: InputMaterial::LocalHTLC {
1740 preimage: if !htlc.offered {
1741 if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1742 Some(preimage.clone())
1744 // We can't build an HTLC-Success transaction without the preimage
1748 amount: htlc.amount_msat,
1750 watch_outputs.push(commitment_tx.output[transaction_output_index as usize].clone());
1754 (claim_requests, watch_outputs, broadcasted_local_revokable_script)
1757 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1758 /// revoked using data in local_claimable_outpoints.
1759 /// Should not be used if check_spend_revoked_transaction succeeds.
1760 fn check_spend_local_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) where L::Target: Logger {
1761 let commitment_txid = tx.txid();
1762 let mut claim_requests = Vec::new();
1763 let mut watch_outputs = Vec::new();
1765 macro_rules! wait_threshold_conf {
1766 ($height: expr, $source: expr, $commitment_tx: expr, $payment_hash: expr) => {
1767 log_trace!(logger, "Failing HTLC with payment_hash {} from {} local commitment tx due to broadcast of transaction, waiting confirmation (at height{})", log_bytes!($payment_hash.0), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1768 match self.onchain_events_waiting_threshold_conf.entry($height + ANTI_REORG_DELAY - 1) {
1769 hash_map::Entry::Occupied(mut entry) => {
1770 let e = entry.get_mut();
1771 e.retain(|ref event| {
1773 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1774 return htlc_update.0 != $source
1779 e.push(OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)});
1781 hash_map::Entry::Vacant(entry) => {
1782 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)}]);
1788 macro_rules! append_onchain_update {
1789 ($updates: expr) => {
1790 claim_requests = $updates.0;
1791 watch_outputs.append(&mut $updates.1);
1792 self.broadcasted_local_revokable_script = $updates.2;
1796 // HTLCs set may differ between last and previous local commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
1797 let mut is_local_tx = false;
1799 if self.current_local_commitment_tx.txid == commitment_txid {
1801 log_trace!(logger, "Got latest local commitment tx broadcast, searching for available HTLCs to claim");
1802 let mut res = self.broadcast_by_local_state(tx, &self.current_local_commitment_tx);
1803 append_onchain_update!(res);
1804 } else if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1805 if local_tx.txid == commitment_txid {
1807 log_trace!(logger, "Got previous local commitment tx broadcast, searching for available HTLCs to claim");
1808 let mut res = self.broadcast_by_local_state(tx, local_tx);
1809 append_onchain_update!(res);
1813 macro_rules! fail_dust_htlcs_after_threshold_conf {
1814 ($local_tx: expr) => {
1815 for &(ref htlc, _, ref source) in &$local_tx.htlc_outputs {
1816 if htlc.transaction_output_index.is_none() {
1817 if let &Some(ref source) = source {
1818 wait_threshold_conf!(height, source.clone(), "lastest", htlc.payment_hash.clone());
1826 fail_dust_htlcs_after_threshold_conf!(self.current_local_commitment_tx);
1827 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1828 fail_dust_htlcs_after_threshold_conf!(local_tx);
1832 (claim_requests, (commitment_txid, watch_outputs))
1835 /// Used by ChannelManager deserialization to broadcast the latest local state if its copy of
1836 /// the Channel was out-of-date. You may use it to get a broadcastable local toxic tx in case of
1837 /// fallen-behind, i.e when receiving a channel_reestablish with a proof that our remote side knows
1838 /// a higher revocation secret than the local commitment number we are aware of. Broadcasting these
1839 /// transactions are UNSAFE, as they allow remote side to punish you. Nevertheless you may want to
1840 /// broadcast them if remote don't close channel with his higher commitment transaction after a
1841 /// substantial amount of time (a month or even a year) to get back funds. Best may be to contact
1842 /// out-of-band the other node operator to coordinate with him if option is available to you.
1843 /// In any-case, choice is up to the user.
1844 pub fn get_latest_local_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1845 log_trace!(logger, "Getting signed latest local commitment transaction!");
1846 self.local_tx_signed = true;
1847 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_local_tx(&self.funding_redeemscript) {
1848 let txid = commitment_tx.txid();
1849 let mut res = vec![commitment_tx];
1850 for htlc in self.current_local_commitment_tx.htlc_outputs.iter() {
1851 if let Some(vout) = htlc.0.transaction_output_index {
1852 let preimage = if !htlc.0.offered {
1853 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1854 // We can't build an HTLC-Success transaction without the preimage
1858 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
1859 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1864 // 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.
1865 // The data will be re-generated and tracked in check_spend_local_transaction if we get a confirmation.
1871 /// Unsafe test-only version of get_latest_local_commitment_txn used by our test framework
1872 /// to bypass LocalCommitmentTransaction state update lockdown after signature and generate
1873 /// revoked commitment transaction.
1875 pub fn unsafe_get_latest_local_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1876 log_trace!(logger, "Getting signed copy of latest local commitment transaction!");
1877 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_copy_local_tx(&self.funding_redeemscript) {
1878 let txid = commitment_tx.txid();
1879 let mut res = vec![commitment_tx];
1880 for htlc in self.current_local_commitment_tx.htlc_outputs.iter() {
1881 if let Some(vout) = htlc.0.transaction_output_index {
1882 let preimage = if !htlc.0.offered {
1883 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1884 // We can't build an HTLC-Success transaction without the preimage
1888 if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
1889 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1899 /// Called by SimpleManyChannelMonitor::block_connected, which implements
1900 /// ChainListener::block_connected.
1901 /// Eventually this should be pub and, roughly, implement ChainListener, however this requires
1902 /// &mut self, as well as returns new spendable outputs and outpoints to watch for spending of
1904 fn block_connected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, txn_matched: &[(usize, &Transaction)], height: u32, broadcaster: B, fee_estimator: F, logger: L)-> Vec<(Txid, Vec<TxOut>)>
1905 where B::Target: BroadcasterInterface,
1906 F::Target: FeeEstimator,
1909 for &(_, tx) in txn_matched {
1910 let mut output_val = 0;
1911 for out in tx.output.iter() {
1912 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1913 output_val += out.value;
1914 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1918 let block_hash = header.bitcoin_hash();
1919 log_trace!(logger, "Block {} at height {} connected with {} txn matched", block_hash, height, txn_matched.len());
1921 let mut watch_outputs = Vec::new();
1922 let mut claimable_outpoints = Vec::new();
1923 for &(_, tx) in txn_matched {
1924 if tx.input.len() == 1 {
1925 // Assuming our keys were not leaked (in which case we're screwed no matter what),
1926 // commitment transactions and HTLC transactions will all only ever have one input,
1927 // which is an easy way to filter out any potential non-matching txn for lazy
1929 let prevout = &tx.input[0].previous_output;
1930 if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
1931 if (tx.input[0].sequence >> 8*3) as u8 == 0x80 && (tx.lock_time >> 8*3) as u8 == 0x20 {
1932 let (mut new_outpoints, new_outputs) = self.check_spend_remote_transaction(&tx, height, &logger);
1933 if !new_outputs.1.is_empty() {
1934 watch_outputs.push(new_outputs);
1936 if new_outpoints.is_empty() {
1937 let (mut new_outpoints, new_outputs) = self.check_spend_local_transaction(&tx, height, &logger);
1938 if !new_outputs.1.is_empty() {
1939 watch_outputs.push(new_outputs);
1941 claimable_outpoints.append(&mut new_outpoints);
1943 claimable_outpoints.append(&mut new_outpoints);
1946 if let Some(&(commitment_number, _)) = self.remote_commitment_txn_on_chain.get(&prevout.txid) {
1947 let (mut new_outpoints, new_outputs_option) = self.check_spend_remote_htlc(&tx, commitment_number, height, &logger);
1948 claimable_outpoints.append(&mut new_outpoints);
1949 if let Some(new_outputs) = new_outputs_option {
1950 watch_outputs.push(new_outputs);
1955 // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
1956 // can also be resolved in a few other ways which can have more than one output. Thus,
1957 // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
1958 self.is_resolving_htlc_output(&tx, height, &logger);
1960 self.is_paying_spendable_output(&tx, height, &logger);
1962 let should_broadcast = self.would_broadcast_at_height(height, &logger);
1963 if should_broadcast {
1964 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() }});
1966 if should_broadcast {
1967 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_local_tx(&self.funding_redeemscript) {
1968 let (mut new_outpoints, new_outputs, _) = self.broadcast_by_local_state(&commitment_tx, &self.current_local_commitment_tx);
1969 if !new_outputs.is_empty() {
1970 watch_outputs.push((self.current_local_commitment_tx.txid.clone(), new_outputs));
1972 claimable_outpoints.append(&mut new_outpoints);
1975 if let Some(events) = self.onchain_events_waiting_threshold_conf.remove(&height) {
1978 OnchainEvent::HTLCUpdate { htlc_update } => {
1979 log_trace!(logger, "HTLC {} failure update has got enough confirmations to be passed upstream", log_bytes!((htlc_update.1).0));
1980 self.pending_htlcs_updated.push(HTLCUpdate {
1981 payment_hash: htlc_update.1,
1982 payment_preimage: None,
1983 source: htlc_update.0,
1986 OnchainEvent::MaturingOutput { descriptor } => {
1987 log_trace!(logger, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
1988 self.pending_events.push(events::Event::SpendableOutputs {
1989 outputs: vec![descriptor]
1995 self.onchain_tx_handler.block_connected(txn_matched, claimable_outpoints, height, &*broadcaster, &*fee_estimator, &*logger);
1997 self.last_block_hash = block_hash;
1998 for &(ref txid, ref output_scripts) in watch_outputs.iter() {
1999 self.outputs_to_watch.insert(txid.clone(), output_scripts.iter().map(|o| o.script_pubkey.clone()).collect());
2005 fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, height: u32, broadcaster: B, fee_estimator: F, logger: L)
2006 where B::Target: BroadcasterInterface,
2007 F::Target: FeeEstimator,
2010 let block_hash = header.bitcoin_hash();
2011 log_trace!(logger, "Block {} at height {} disconnected", block_hash, height);
2013 if let Some(_) = self.onchain_events_waiting_threshold_conf.remove(&(height + ANTI_REORG_DELAY - 1)) {
2015 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
2016 //- maturing spendable output has transaction paying us has been disconnected
2019 self.onchain_tx_handler.block_disconnected(height, broadcaster, fee_estimator, logger);
2021 self.last_block_hash = block_hash;
2024 pub(super) fn would_broadcast_at_height<L: Deref>(&self, height: u32, logger: &L) -> bool where L::Target: Logger {
2025 // We need to consider all HTLCs which are:
2026 // * in any unrevoked remote commitment transaction, as they could broadcast said
2027 // transactions and we'd end up in a race, or
2028 // * are in our latest local commitment transaction, as this is the thing we will
2029 // broadcast if we go on-chain.
2030 // Note that we consider HTLCs which were below dust threshold here - while they don't
2031 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
2032 // to the source, and if we don't fail the channel we will have to ensure that the next
2033 // updates that peer sends us are update_fails, failing the channel if not. It's probably
2034 // easier to just fail the channel as this case should be rare enough anyway.
2035 macro_rules! scan_commitment {
2036 ($htlcs: expr, $local_tx: expr) => {
2037 for ref htlc in $htlcs {
2038 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
2039 // chain with enough room to claim the HTLC without our counterparty being able to
2040 // time out the HTLC first.
2041 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
2042 // concern is being able to claim the corresponding inbound HTLC (on another
2043 // channel) before it expires. In fact, we don't even really care if our
2044 // counterparty here claims such an outbound HTLC after it expired as long as we
2045 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
2046 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
2047 // we give ourselves a few blocks of headroom after expiration before going
2048 // on-chain for an expired HTLC.
2049 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
2050 // from us until we've reached the point where we go on-chain with the
2051 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
2052 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
2053 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
2054 // inbound_cltv == height + CLTV_CLAIM_BUFFER
2055 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
2056 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
2057 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
2058 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
2059 // The final, above, condition is checked for statically in channelmanager
2060 // with CHECK_CLTV_EXPIRY_SANITY_2.
2061 let htlc_outbound = $local_tx == htlc.offered;
2062 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
2063 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
2064 log_info!(logger, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
2071 scan_commitment!(self.current_local_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
2073 if let Some(ref txid) = self.current_remote_commitment_txid {
2074 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(txid) {
2075 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2078 if let Some(ref txid) = self.prev_remote_commitment_txid {
2079 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(txid) {
2080 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2087 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a local
2088 /// or remote commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
2089 fn is_resolving_htlc_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2090 'outer_loop: for input in &tx.input {
2091 let mut payment_data = None;
2092 let revocation_sig_claim = (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && input.witness[1].len() == 33)
2093 || (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && input.witness[1].len() == 33);
2094 let accepted_preimage_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::AcceptedHTLC);
2095 let offered_preimage_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC);
2097 macro_rules! log_claim {
2098 ($tx_info: expr, $local_tx: expr, $htlc: expr, $source_avail: expr) => {
2099 // We found the output in question, but aren't failing it backwards
2100 // as we have no corresponding source and no valid remote commitment txid
2101 // to try a weak source binding with same-hash, same-value still-valid offered HTLC.
2102 // This implies either it is an inbound HTLC or an outbound HTLC on a revoked transaction.
2103 let outbound_htlc = $local_tx == $htlc.offered;
2104 if ($local_tx && revocation_sig_claim) ||
2105 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
2106 log_error!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
2107 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2108 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2109 if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back" });
2111 log_info!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
2112 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2113 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2114 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
2119 macro_rules! check_htlc_valid_remote {
2120 ($remote_txid: expr, $htlc_output: expr) => {
2121 if let Some(txid) = $remote_txid {
2122 for &(ref pending_htlc, ref pending_source) in self.remote_claimable_outpoints.get(&txid).unwrap() {
2123 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
2124 if let &Some(ref source) = pending_source {
2125 log_claim!("revoked remote commitment tx", false, pending_htlc, true);
2126 payment_data = Some(((**source).clone(), $htlc_output.payment_hash));
2135 macro_rules! scan_commitment {
2136 ($htlcs: expr, $tx_info: expr, $local_tx: expr) => {
2137 for (ref htlc_output, source_option) in $htlcs {
2138 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
2139 if let Some(ref source) = source_option {
2140 log_claim!($tx_info, $local_tx, htlc_output, true);
2141 // We have a resolution of an HTLC either from one of our latest
2142 // local commitment transactions or an unrevoked remote commitment
2143 // transaction. This implies we either learned a preimage, the HTLC
2144 // has timed out, or we screwed up. In any case, we should now
2145 // resolve the source HTLC with the original sender.
2146 payment_data = Some(((*source).clone(), htlc_output.payment_hash));
2147 } else if !$local_tx {
2148 check_htlc_valid_remote!(self.current_remote_commitment_txid, htlc_output);
2149 if payment_data.is_none() {
2150 check_htlc_valid_remote!(self.prev_remote_commitment_txid, htlc_output);
2153 if payment_data.is_none() {
2154 log_claim!($tx_info, $local_tx, htlc_output, false);
2155 continue 'outer_loop;
2162 if input.previous_output.txid == self.current_local_commitment_tx.txid {
2163 scan_commitment!(self.current_local_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2164 "our latest local commitment tx", true);
2166 if let Some(ref prev_local_signed_commitment_tx) = self.prev_local_signed_commitment_tx {
2167 if input.previous_output.txid == prev_local_signed_commitment_tx.txid {
2168 scan_commitment!(prev_local_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2169 "our previous local commitment tx", true);
2172 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(&input.previous_output.txid) {
2173 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
2174 "remote commitment tx", false);
2177 // Check that scan_commitment, above, decided there is some source worth relaying an
2178 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
2179 if let Some((source, payment_hash)) = payment_data {
2180 let mut payment_preimage = PaymentPreimage([0; 32]);
2181 if accepted_preimage_claim {
2182 if !self.pending_htlcs_updated.iter().any(|update| update.source == source) {
2183 payment_preimage.0.copy_from_slice(&input.witness[3]);
2184 self.pending_htlcs_updated.push(HTLCUpdate {
2186 payment_preimage: Some(payment_preimage),
2190 } else if offered_preimage_claim {
2191 if !self.pending_htlcs_updated.iter().any(|update| update.source == source) {
2192 payment_preimage.0.copy_from_slice(&input.witness[1]);
2193 self.pending_htlcs_updated.push(HTLCUpdate {
2195 payment_preimage: Some(payment_preimage),
2200 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);
2201 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2202 hash_map::Entry::Occupied(mut entry) => {
2203 let e = entry.get_mut();
2204 e.retain(|ref event| {
2206 OnchainEvent::HTLCUpdate { ref htlc_update } => {
2207 return htlc_update.0 != source
2212 e.push(OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)});
2214 hash_map::Entry::Vacant(entry) => {
2215 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)}]);
2223 /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
2224 fn is_paying_spendable_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2225 let mut spendable_output = None;
2226 for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
2227 if outp.script_pubkey == self.destination_script {
2228 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2229 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2230 output: outp.clone(),
2233 } else if let Some(ref broadcasted_local_revokable_script) = self.broadcasted_local_revokable_script {
2234 if broadcasted_local_revokable_script.0 == outp.script_pubkey {
2235 spendable_output = Some(SpendableOutputDescriptor::DynamicOutputP2WSH {
2236 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2237 per_commitment_point: broadcasted_local_revokable_script.1,
2238 to_self_delay: self.on_local_tx_csv,
2239 output: outp.clone(),
2240 key_derivation_params: self.keys.key_derivation_params(),
2241 remote_revocation_pubkey: broadcasted_local_revokable_script.2.clone(),
2245 } else if self.remote_payment_script == outp.script_pubkey {
2246 spendable_output = Some(SpendableOutputDescriptor::StaticOutputRemotePayment {
2247 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2248 output: outp.clone(),
2249 key_derivation_params: self.keys.key_derivation_params(),
2252 } else if outp.script_pubkey == self.shutdown_script {
2253 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2254 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2255 output: outp.clone(),
2259 if let Some(spendable_output) = spendable_output {
2260 log_trace!(logger, "Maturing {} until {}", log_spendable!(spendable_output), height + ANTI_REORG_DELAY - 1);
2261 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2262 hash_map::Entry::Occupied(mut entry) => {
2263 let e = entry.get_mut();
2264 e.push(OnchainEvent::MaturingOutput { descriptor: spendable_output });
2266 hash_map::Entry::Vacant(entry) => {
2267 entry.insert(vec![OnchainEvent::MaturingOutput { descriptor: spendable_output }]);
2274 const MAX_ALLOC_SIZE: usize = 64*1024;
2276 impl<ChanSigner: ChannelKeys + Readable> Readable for (BlockHash, ChannelMonitor<ChanSigner>) {
2277 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
2278 macro_rules! unwrap_obj {
2282 Err(_) => return Err(DecodeError::InvalidValue),
2287 let _ver: u8 = Readable::read(reader)?;
2288 let min_ver: u8 = Readable::read(reader)?;
2289 if min_ver > SERIALIZATION_VERSION {
2290 return Err(DecodeError::UnknownVersion);
2293 let latest_update_id: u64 = Readable::read(reader)?;
2294 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
2296 let destination_script = Readable::read(reader)?;
2297 let broadcasted_local_revokable_script = match <u8 as Readable>::read(reader)? {
2299 let revokable_address = Readable::read(reader)?;
2300 let per_commitment_point = Readable::read(reader)?;
2301 let revokable_script = Readable::read(reader)?;
2302 Some((revokable_address, per_commitment_point, revokable_script))
2305 _ => return Err(DecodeError::InvalidValue),
2307 let remote_payment_script = Readable::read(reader)?;
2308 let shutdown_script = Readable::read(reader)?;
2310 let keys = Readable::read(reader)?;
2311 // Technically this can fail and serialize fail a round-trip, but only for serialization of
2312 // barely-init'd ChannelMonitors that we can't do anything with.
2313 let outpoint = OutPoint {
2314 txid: Readable::read(reader)?,
2315 index: Readable::read(reader)?,
2317 let funding_info = (outpoint, Readable::read(reader)?);
2318 let current_remote_commitment_txid = Readable::read(reader)?;
2319 let prev_remote_commitment_txid = Readable::read(reader)?;
2321 let remote_tx_cache = Readable::read(reader)?;
2322 let funding_redeemscript = Readable::read(reader)?;
2323 let channel_value_satoshis = Readable::read(reader)?;
2325 let their_cur_revocation_points = {
2326 let first_idx = <U48 as Readable>::read(reader)?.0;
2330 let first_point = Readable::read(reader)?;
2331 let second_point_slice: [u8; 33] = Readable::read(reader)?;
2332 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
2333 Some((first_idx, first_point, None))
2335 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
2340 let on_local_tx_csv: u16 = Readable::read(reader)?;
2342 let commitment_secrets = Readable::read(reader)?;
2344 macro_rules! read_htlc_in_commitment {
2347 let offered: bool = Readable::read(reader)?;
2348 let amount_msat: u64 = Readable::read(reader)?;
2349 let cltv_expiry: u32 = Readable::read(reader)?;
2350 let payment_hash: PaymentHash = Readable::read(reader)?;
2351 let transaction_output_index: Option<u32> = Readable::read(reader)?;
2353 HTLCOutputInCommitment {
2354 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
2360 let remote_claimable_outpoints_len: u64 = Readable::read(reader)?;
2361 let mut remote_claimable_outpoints = HashMap::with_capacity(cmp::min(remote_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
2362 for _ in 0..remote_claimable_outpoints_len {
2363 let txid: Txid = Readable::read(reader)?;
2364 let htlcs_count: u64 = Readable::read(reader)?;
2365 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
2366 for _ in 0..htlcs_count {
2367 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
2369 if let Some(_) = remote_claimable_outpoints.insert(txid, htlcs) {
2370 return Err(DecodeError::InvalidValue);
2374 let remote_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
2375 let mut remote_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(remote_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
2376 for _ in 0..remote_commitment_txn_on_chain_len {
2377 let txid: Txid = Readable::read(reader)?;
2378 let commitment_number = <U48 as Readable>::read(reader)?.0;
2379 let outputs_count = <u64 as Readable>::read(reader)?;
2380 let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 8));
2381 for _ in 0..outputs_count {
2382 outputs.push(Readable::read(reader)?);
2384 if let Some(_) = remote_commitment_txn_on_chain.insert(txid, (commitment_number, outputs)) {
2385 return Err(DecodeError::InvalidValue);
2389 let remote_hash_commitment_number_len: u64 = Readable::read(reader)?;
2390 let mut remote_hash_commitment_number = HashMap::with_capacity(cmp::min(remote_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
2391 for _ in 0..remote_hash_commitment_number_len {
2392 let payment_hash: PaymentHash = Readable::read(reader)?;
2393 let commitment_number = <U48 as Readable>::read(reader)?.0;
2394 if let Some(_) = remote_hash_commitment_number.insert(payment_hash, commitment_number) {
2395 return Err(DecodeError::InvalidValue);
2399 macro_rules! read_local_tx {
2402 let txid = Readable::read(reader)?;
2403 let revocation_key = Readable::read(reader)?;
2404 let a_htlc_key = Readable::read(reader)?;
2405 let b_htlc_key = Readable::read(reader)?;
2406 let delayed_payment_key = Readable::read(reader)?;
2407 let per_commitment_point = Readable::read(reader)?;
2408 let feerate_per_kw: u32 = Readable::read(reader)?;
2410 let htlcs_len: u64 = Readable::read(reader)?;
2411 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_len as usize, MAX_ALLOC_SIZE / 128));
2412 for _ in 0..htlcs_len {
2413 let htlc = read_htlc_in_commitment!();
2414 let sigs = match <u8 as Readable>::read(reader)? {
2416 1 => Some(Readable::read(reader)?),
2417 _ => return Err(DecodeError::InvalidValue),
2419 htlcs.push((htlc, sigs, Readable::read(reader)?));
2424 revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, per_commitment_point, feerate_per_kw,
2431 let prev_local_signed_commitment_tx = match <u8 as Readable>::read(reader)? {
2434 Some(read_local_tx!())
2436 _ => return Err(DecodeError::InvalidValue),
2438 let current_local_commitment_tx = read_local_tx!();
2440 let current_remote_commitment_number = <U48 as Readable>::read(reader)?.0;
2441 let current_local_commitment_number = <U48 as Readable>::read(reader)?.0;
2443 let payment_preimages_len: u64 = Readable::read(reader)?;
2444 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
2445 for _ in 0..payment_preimages_len {
2446 let preimage: PaymentPreimage = Readable::read(reader)?;
2447 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2448 if let Some(_) = payment_preimages.insert(hash, preimage) {
2449 return Err(DecodeError::InvalidValue);
2453 let pending_htlcs_updated_len: u64 = Readable::read(reader)?;
2454 let mut pending_htlcs_updated = Vec::with_capacity(cmp::min(pending_htlcs_updated_len as usize, MAX_ALLOC_SIZE / (32 + 8*3)));
2455 for _ in 0..pending_htlcs_updated_len {
2456 pending_htlcs_updated.push(Readable::read(reader)?);
2459 let pending_events_len: u64 = Readable::read(reader)?;
2460 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<events::Event>()));
2461 for _ in 0..pending_events_len {
2462 if let Some(event) = MaybeReadable::read(reader)? {
2463 pending_events.push(event);
2467 let last_block_hash: BlockHash = Readable::read(reader)?;
2469 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
2470 let mut onchain_events_waiting_threshold_conf = HashMap::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
2471 for _ in 0..waiting_threshold_conf_len {
2472 let height_target = Readable::read(reader)?;
2473 let events_len: u64 = Readable::read(reader)?;
2474 let mut events = Vec::with_capacity(cmp::min(events_len as usize, MAX_ALLOC_SIZE / 128));
2475 for _ in 0..events_len {
2476 let ev = match <u8 as Readable>::read(reader)? {
2478 let htlc_source = Readable::read(reader)?;
2479 let hash = Readable::read(reader)?;
2480 OnchainEvent::HTLCUpdate {
2481 htlc_update: (htlc_source, hash)
2485 let descriptor = Readable::read(reader)?;
2486 OnchainEvent::MaturingOutput {
2490 _ => return Err(DecodeError::InvalidValue),
2494 onchain_events_waiting_threshold_conf.insert(height_target, events);
2497 let outputs_to_watch_len: u64 = Readable::read(reader)?;
2498 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>>())));
2499 for _ in 0..outputs_to_watch_len {
2500 let txid = Readable::read(reader)?;
2501 let outputs_len: u64 = Readable::read(reader)?;
2502 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Script>()));
2503 for _ in 0..outputs_len {
2504 outputs.push(Readable::read(reader)?);
2506 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
2507 return Err(DecodeError::InvalidValue);
2510 let onchain_tx_handler = Readable::read(reader)?;
2512 let lockdown_from_offchain = Readable::read(reader)?;
2513 let local_tx_signed = Readable::read(reader)?;
2515 Ok((last_block_hash.clone(), ChannelMonitor {
2517 commitment_transaction_number_obscure_factor,
2520 broadcasted_local_revokable_script,
2521 remote_payment_script,
2526 current_remote_commitment_txid,
2527 prev_remote_commitment_txid,
2530 funding_redeemscript,
2531 channel_value_satoshis,
2532 their_cur_revocation_points,
2537 remote_claimable_outpoints,
2538 remote_commitment_txn_on_chain,
2539 remote_hash_commitment_number,
2541 prev_local_signed_commitment_tx,
2542 current_local_commitment_tx,
2543 current_remote_commitment_number,
2544 current_local_commitment_number,
2547 pending_htlcs_updated,
2550 onchain_events_waiting_threshold_conf,
2555 lockdown_from_offchain,
2559 secp_ctx: Secp256k1::new(),
2566 use bitcoin::blockdata::script::{Script, Builder};
2567 use bitcoin::blockdata::opcodes;
2568 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, SigHashType};
2569 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
2570 use bitcoin::util::bip143;
2571 use bitcoin::hashes::Hash;
2572 use bitcoin::hashes::sha256::Hash as Sha256;
2573 use bitcoin::hashes::hex::FromHex;
2574 use bitcoin::hash_types::Txid;
2576 use chain::transaction::OutPoint;
2577 use ln::channelmanager::{PaymentPreimage, PaymentHash};
2578 use ln::channelmonitor::ChannelMonitor;
2579 use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
2581 use ln::chan_utils::{HTLCOutputInCommitment, LocalCommitmentTransaction};
2582 use util::test_utils::TestLogger;
2583 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
2584 use bitcoin::secp256k1::Secp256k1;
2586 use chain::keysinterface::InMemoryChannelKeys;
2589 fn test_prune_preimages() {
2590 let secp_ctx = Secp256k1::new();
2591 let logger = Arc::new(TestLogger::new());
2593 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
2594 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2596 let mut preimages = Vec::new();
2599 let preimage = PaymentPreimage([i; 32]);
2600 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2601 preimages.push((preimage, hash));
2605 macro_rules! preimages_slice_to_htlc_outputs {
2606 ($preimages_slice: expr) => {
2608 let mut res = Vec::new();
2609 for (idx, preimage) in $preimages_slice.iter().enumerate() {
2610 res.push((HTLCOutputInCommitment {
2614 payment_hash: preimage.1.clone(),
2615 transaction_output_index: Some(idx as u32),
2622 macro_rules! preimages_to_local_htlcs {
2623 ($preimages_slice: expr) => {
2625 let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2626 let res: Vec<_> = inp.drain(..).map(|e| { (e.0, None, e.1) }).collect();
2632 macro_rules! test_preimages_exist {
2633 ($preimages_slice: expr, $monitor: expr) => {
2634 for preimage in $preimages_slice {
2635 assert!($monitor.payment_preimages.contains_key(&preimage.1));
2640 let keys = InMemoryChannelKeys::new(
2642 SecretKey::from_slice(&[41; 32]).unwrap(),
2643 SecretKey::from_slice(&[41; 32]).unwrap(),
2644 SecretKey::from_slice(&[41; 32]).unwrap(),
2645 SecretKey::from_slice(&[41; 32]).unwrap(),
2646 SecretKey::from_slice(&[41; 32]).unwrap(),
2652 // Prune with one old state and a local commitment tx holding a few overlaps with the
2654 let mut monitor = ChannelMonitor::new(keys,
2655 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()), 0, &Script::new(),
2656 (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
2657 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
2658 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
2659 10, Script::new(), 46, 0, LocalCommitmentTransaction::dummy());
2661 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..10])).unwrap();
2662 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
2663 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
2664 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
2665 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
2666 for &(ref preimage, ref hash) in preimages.iter() {
2667 monitor.provide_payment_preimage(hash, preimage);
2670 // Now provide a secret, pruning preimages 10-15
2671 let mut secret = [0; 32];
2672 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2673 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2674 assert_eq!(monitor.payment_preimages.len(), 15);
2675 test_preimages_exist!(&preimages[0..10], monitor);
2676 test_preimages_exist!(&preimages[15..20], monitor);
2678 // Now provide a further secret, pruning preimages 15-17
2679 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2680 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2681 assert_eq!(monitor.payment_preimages.len(), 13);
2682 test_preimages_exist!(&preimages[0..10], monitor);
2683 test_preimages_exist!(&preimages[17..20], monitor);
2685 // Now update local commitment tx info, pruning only element 18 as we still care about the
2686 // previous commitment tx's preimages too
2687 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..5])).unwrap();
2688 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2689 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2690 assert_eq!(monitor.payment_preimages.len(), 12);
2691 test_preimages_exist!(&preimages[0..10], monitor);
2692 test_preimages_exist!(&preimages[18..20], monitor);
2694 // But if we do it again, we'll prune 5-10
2695 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..3])).unwrap();
2696 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2697 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2698 assert_eq!(monitor.payment_preimages.len(), 5);
2699 test_preimages_exist!(&preimages[0..5], monitor);
2703 fn test_claim_txn_weight_computation() {
2704 // We test Claim txn weight, knowing that we want expected weigth and
2705 // not actual case to avoid sigs and time-lock delays hell variances.
2707 let secp_ctx = Secp256k1::new();
2708 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
2709 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
2710 let mut sum_actual_sigs = 0;
2712 macro_rules! sign_input {
2713 ($sighash_parts: expr, $input: expr, $idx: expr, $amount: expr, $input_type: expr, $sum_actual_sigs: expr) => {
2714 let htlc = HTLCOutputInCommitment {
2715 offered: if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::OfferedHTLC { true } else { false },
2717 cltv_expiry: 2 << 16,
2718 payment_hash: PaymentHash([1; 32]),
2719 transaction_output_index: Some($idx),
2721 let redeem_script = if *$input_type == InputDescriptors::RevokedOutput { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &pubkey, &pubkey, &pubkey) };
2722 let sighash = hash_to_message!(&$sighash_parts.sighash_all(&$input, &redeem_script, $amount)[..]);
2723 let sig = secp_ctx.sign(&sighash, &privkey);
2724 $input.witness.push(sig.serialize_der().to_vec());
2725 $input.witness[0].push(SigHashType::All as u8);
2726 sum_actual_sigs += $input.witness[0].len();
2727 if *$input_type == InputDescriptors::RevokedOutput {
2728 $input.witness.push(vec!(1));
2729 } else if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::RevokedReceivedHTLC {
2730 $input.witness.push(pubkey.clone().serialize().to_vec());
2731 } else if *$input_type == InputDescriptors::ReceivedHTLC {
2732 $input.witness.push(vec![0]);
2734 $input.witness.push(PaymentPreimage([1; 32]).0.to_vec());
2736 $input.witness.push(redeem_script.into_bytes());
2737 println!("witness[0] {}", $input.witness[0].len());
2738 println!("witness[1] {}", $input.witness[1].len());
2739 println!("witness[2] {}", $input.witness[2].len());
2743 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
2744 let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
2746 // Justice tx with 1 to_local, 2 revoked offered HTLCs, 1 revoked received HTLCs
2747 let mut claim_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2749 claim_tx.input.push(TxIn {
2750 previous_output: BitcoinOutPoint {
2754 script_sig: Script::new(),
2755 sequence: 0xfffffffd,
2756 witness: Vec::new(),
2759 claim_tx.output.push(TxOut {
2760 script_pubkey: script_pubkey.clone(),
2763 let base_weight = claim_tx.get_weight();
2764 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2765 let inputs_des = vec![InputDescriptors::RevokedOutput, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedReceivedHTLC];
2766 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2767 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2769 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));
2771 // Claim tx with 1 offered HTLCs, 3 received HTLCs
2772 claim_tx.input.clear();
2773 sum_actual_sigs = 0;
2775 claim_tx.input.push(TxIn {
2776 previous_output: BitcoinOutPoint {
2780 script_sig: Script::new(),
2781 sequence: 0xfffffffd,
2782 witness: Vec::new(),
2785 let base_weight = claim_tx.get_weight();
2786 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2787 let inputs_des = vec![InputDescriptors::OfferedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC];
2788 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2789 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2791 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));
2793 // Justice tx with 1 revoked HTLC-Success tx output
2794 claim_tx.input.clear();
2795 sum_actual_sigs = 0;
2796 claim_tx.input.push(TxIn {
2797 previous_output: BitcoinOutPoint {
2801 script_sig: Script::new(),
2802 sequence: 0xfffffffd,
2803 witness: Vec::new(),
2805 let base_weight = claim_tx.get_weight();
2806 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2807 let inputs_des = vec![InputDescriptors::RevokedOutput];
2808 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2809 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2811 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));
2814 // Further testing is done in the ChannelManager integration tests.