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 latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date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, ChainWatchInterface, 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, C: Deref>
165 where T::Target: BroadcasterInterface,
166 F::Target: FeeEstimator,
168 C::Target: ChainWatchInterface,
170 #[cfg(test)] // Used in ChannelManager tests to manipulate channels directly
171 pub monitors: Mutex<HashMap<Key, ChannelMonitor<ChanSigner>>>,
173 monitors: Mutex<HashMap<Key, ChannelMonitor<ChanSigner>>>,
174 watch_events: Mutex<WatchEventQueue>,
181 struct WatchEventQueue {
182 watched: ChainWatchedUtil,
183 events: Vec<chain::WatchEvent>,
186 impl WatchEventQueue {
189 watched: ChainWatchedUtil::new(),
194 fn watch_tx(&mut self, txid: &Txid, script_pubkey: &Script) {
195 if self.watched.register_tx(txid, script_pubkey) {
196 self.events.push(chain::WatchEvent::WatchTransaction {
198 script_pubkey: script_pubkey.clone()
203 fn watch_output(&mut self, outpoint: (&Txid, usize), script_pubkey: &Script) {
204 let (txid, index) = outpoint;
205 if self.watched.register_outpoint((*txid, index as u32), script_pubkey) {
206 self.events.push(chain::WatchEvent::WatchOutput {
211 script_pubkey: script_pubkey.clone(),
216 fn dequeue_events(&mut self) -> Vec<chain::WatchEvent> {
217 let mut pending_events = Vec::with_capacity(self.events.len());
218 pending_events.append(&mut self.events);
223 impl<Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys, T: Deref + Sync + Send, F: Deref + Sync + Send, L: Deref + Sync + Send, C: Deref + Sync + Send>
224 ChainListener for SimpleManyChannelMonitor<Key, ChanSigner, T, F, L, C>
225 where T::Target: BroadcasterInterface,
226 F::Target: FeeEstimator,
228 C::Target: ChainWatchInterface,
230 fn block_connected(&self, header: &BlockHeader, txdata: &[(usize, &Transaction)], height: u32) {
231 let mut watch_events = self.watch_events.lock().unwrap();
232 let matched_txn: Vec<_> = txdata.iter().filter(|&&(_, tx)| watch_events.watched.does_match_tx(tx)).map(|e| *e).collect();
234 let mut monitors = self.monitors.lock().unwrap();
235 for monitor in monitors.values_mut() {
236 let txn_outputs = monitor.block_connected(header, &matched_txn, height, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
238 for (ref txid, ref outputs) in txn_outputs {
239 for (idx, output) in outputs.iter().enumerate() {
240 watch_events.watch_output((txid, idx), &output.script_pubkey);
247 fn block_disconnected(&self, header: &BlockHeader, disconnected_height: u32) {
248 let mut monitors = self.monitors.lock().unwrap();
249 for monitor in monitors.values_mut() {
250 monitor.block_disconnected(header, disconnected_height, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
255 impl<Key : Send + cmp::Eq + hash::Hash + 'static, ChanSigner: ChannelKeys, T: Deref, F: Deref, L: Deref, C: Deref> SimpleManyChannelMonitor<Key, ChanSigner, T, F, L, C>
256 where T::Target: BroadcasterInterface,
257 F::Target: FeeEstimator,
259 C::Target: ChainWatchInterface,
261 /// Creates a new object which can be used to monitor several channels given the chain
262 /// interface with which to register to receive notifications.
263 pub fn new(chain_monitor: C, broadcaster: T, logger: L, feeest: F) -> SimpleManyChannelMonitor<Key, ChanSigner, T, F, L, C> {
264 let res = SimpleManyChannelMonitor {
265 monitors: Mutex::new(HashMap::new()),
266 watch_events: Mutex::new(WatchEventQueue::new()),
270 fee_estimator: feeest,
276 /// Adds or updates the monitor which monitors the channel referred to by the given key.
277 pub fn add_monitor_by_key(&self, key: Key, monitor: ChannelMonitor<ChanSigner>) -> Result<(), MonitorUpdateError> {
278 let mut watch_events = self.watch_events.lock().unwrap();
279 let mut monitors = self.monitors.lock().unwrap();
280 let entry = match monitors.entry(key) {
281 hash_map::Entry::Occupied(_) => return Err(MonitorUpdateError("Channel monitor for given key is already present")),
282 hash_map::Entry::Vacant(e) => e,
285 let funding_txo = monitor.get_funding_txo();
286 log_trace!(self.logger, "Got new Channel Monitor for channel {}", log_bytes!(funding_txo.0.to_channel_id()[..]));
287 watch_events.watch_tx(&funding_txo.0.txid, &funding_txo.1);
288 watch_events.watch_output((&funding_txo.0.txid, funding_txo.0.index as usize), &funding_txo.1);
289 for (txid, outputs) in monitor.get_outputs_to_watch().iter() {
290 for (idx, script) in outputs.iter().enumerate() {
291 watch_events.watch_output((txid, idx), script);
295 entry.insert(monitor);
299 /// Updates the monitor which monitors the channel referred to by the given key.
300 pub fn update_monitor_by_key(&self, key: Key, update: ChannelMonitorUpdate) -> Result<(), MonitorUpdateError> {
301 let mut monitors = self.monitors.lock().unwrap();
302 match monitors.get_mut(&key) {
303 Some(orig_monitor) => {
304 log_trace!(self.logger, "Updating Channel Monitor for channel {}", log_funding_info!(orig_monitor));
305 orig_monitor.update_monitor(update, &self.broadcaster, &self.logger)
307 None => Err(MonitorUpdateError("No such monitor registered"))
312 impl<ChanSigner: ChannelKeys, T: Deref + Sync + Send, F: Deref + Sync + Send, L: Deref + Sync + Send, C: Deref + Sync + Send> ManyChannelMonitor for SimpleManyChannelMonitor<OutPoint, ChanSigner, T, F, L, C>
313 where T::Target: BroadcasterInterface,
314 F::Target: FeeEstimator,
316 C::Target: ChainWatchInterface,
318 type Keys = ChanSigner;
320 fn add_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor<ChanSigner>) -> Result<(), ChannelMonitorUpdateErr> {
321 match self.add_monitor_by_key(funding_txo, monitor) {
323 Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
327 fn update_monitor(&self, funding_txo: OutPoint, update: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr> {
328 match self.update_monitor_by_key(funding_txo, update) {
330 Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
334 fn get_and_clear_pending_htlcs_updated(&self) -> Vec<HTLCUpdate> {
335 let mut pending_htlcs_updated = Vec::new();
336 for chan in self.monitors.lock().unwrap().values_mut() {
337 pending_htlcs_updated.append(&mut chan.get_and_clear_pending_htlcs_updated());
339 pending_htlcs_updated
343 impl<Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys, T: Deref, F: Deref, L: Deref, C: Deref> events::EventsProvider for SimpleManyChannelMonitor<Key, ChanSigner, T, F, L, C>
344 where T::Target: BroadcasterInterface,
345 F::Target: FeeEstimator,
347 C::Target: ChainWatchInterface,
349 fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
350 let mut pending_events = Vec::new();
351 for chan in self.monitors.lock().unwrap().values_mut() {
352 pending_events.append(&mut chan.get_and_clear_pending_events());
358 impl<Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys, T: Deref, F: Deref, L: Deref, C: Deref> chain::WatchEventProvider for SimpleManyChannelMonitor<Key, ChanSigner, T, F, L, C>
359 where T::Target: BroadcasterInterface,
360 F::Target: FeeEstimator,
362 C::Target: ChainWatchInterface,
364 fn release_pending_watch_events(&self) -> Vec<chain::WatchEvent> {
365 self.watch_events.lock().unwrap().dequeue_events()
369 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
370 /// instead claiming it in its own individual transaction.
371 pub(crate) const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
372 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
373 /// HTLC-Success transaction.
374 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
375 /// transaction confirmed (and we use it in a few more, equivalent, places).
376 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 6;
377 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
378 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
379 /// copies of ChannelMonitors, including watchtowers). We could enforce the contract by failing
380 /// at CLTV expiration height but giving a grace period to our peer may be profitable for us if he
381 /// can provide an over-late preimage. Nevertheless, grace period has to be accounted in our
382 /// CLTV_EXPIRY_DELTA to be secure. Following this policy we may decrease the rate of channel failures
383 /// due to expiration but increase the cost of funds being locked longuer in case of failure.
384 /// This delay also cover a low-power peer being slow to process blocks and so being behind us on
385 /// accurate block height.
386 /// In case of onchain failure to be pass backward we may see the last block of ANTI_REORG_DELAY
387 /// with at worst this delay, so we are not only using this value as a mercy for them but also
388 /// us as a safeguard to delay with enough time.
389 pub(crate) const LATENCY_GRACE_PERIOD_BLOCKS: u32 = 3;
390 /// Number of blocks we wait on seeing a HTLC output being solved before we fail corresponding inbound
391 /// HTLCs. This prevents us from failing backwards and then getting a reorg resulting in us losing money.
392 /// We use also this delay to be sure we can remove our in-flight claim txn from bump candidates buffer.
393 /// It may cause spurrious generation of bumped claim txn but that's allright given the outpoint is already
394 /// solved by a previous claim tx. What we want to avoid is reorg evicting our claim tx and us not
395 /// keeping bumping another claim tx to solve the outpoint.
396 pub(crate) const ANTI_REORG_DELAY: u32 = 6;
397 /// Number of blocks before confirmation at which we fail back an un-relayed HTLC or at which we
398 /// refuse to accept a new HTLC.
400 /// This is used for a few separate purposes:
401 /// 1) if we've received an MPP HTLC to us and it expires within this many blocks and we are
402 /// waiting on additional parts (or waiting on the preimage for any HTLC from the user), we will
404 /// 2) if we receive an HTLC within this many blocks of its expiry (plus one to avoid a race
405 /// condition with the above), we will fail this HTLC without telling the user we received it,
406 /// 3) if we are waiting on a connection or a channel state update to send an HTLC to a peer, and
407 /// that HTLC expires within this many blocks, we will simply fail the HTLC instead.
409 /// (1) is all about protecting us - we need enough time to update the channel state before we hit
410 /// CLTV_CLAIM_BUFFER, at which point we'd go on chain to claim the HTLC with the preimage.
412 /// (2) is the same, but with an additional buffer to avoid accepting an HTLC which is immediately
413 /// in a race condition between the user connecting a block (which would fail it) and the user
414 /// providing us the preimage (which would claim it).
416 /// (3) is about our counterparty - we don't want to relay an HTLC to a counterparty when they may
417 /// end up force-closing the channel on us to claim it.
418 pub(crate) const HTLC_FAIL_BACK_BUFFER: u32 = CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS;
420 #[derive(Clone, PartialEq)]
421 struct LocalSignedTx {
422 /// txid of the transaction in tx, just used to make comparison faster
424 revocation_key: PublicKey,
425 a_htlc_key: PublicKey,
426 b_htlc_key: PublicKey,
427 delayed_payment_key: PublicKey,
428 per_commitment_point: PublicKey,
430 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
433 /// We use this to track remote commitment transactions and htlcs outputs and
434 /// use it to generate any justice or 2nd-stage preimage/timeout transactions.
436 struct RemoteCommitmentTransaction {
437 remote_delayed_payment_base_key: PublicKey,
438 remote_htlc_base_key: PublicKey,
439 on_remote_tx_csv: u16,
440 per_htlc: HashMap<Txid, Vec<HTLCOutputInCommitment>>
443 impl Writeable for RemoteCommitmentTransaction {
444 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
445 self.remote_delayed_payment_base_key.write(w)?;
446 self.remote_htlc_base_key.write(w)?;
447 w.write_all(&byte_utils::be16_to_array(self.on_remote_tx_csv))?;
448 w.write_all(&byte_utils::be64_to_array(self.per_htlc.len() as u64))?;
449 for (ref txid, ref htlcs) in self.per_htlc.iter() {
450 w.write_all(&txid[..])?;
451 w.write_all(&byte_utils::be64_to_array(htlcs.len() as u64))?;
452 for &ref htlc in htlcs.iter() {
459 impl Readable for RemoteCommitmentTransaction {
460 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
461 let remote_commitment_transaction = {
462 let remote_delayed_payment_base_key = Readable::read(r)?;
463 let remote_htlc_base_key = Readable::read(r)?;
464 let on_remote_tx_csv: u16 = Readable::read(r)?;
465 let per_htlc_len: u64 = Readable::read(r)?;
466 let mut per_htlc = HashMap::with_capacity(cmp::min(per_htlc_len as usize, MAX_ALLOC_SIZE / 64));
467 for _ in 0..per_htlc_len {
468 let txid: Txid = Readable::read(r)?;
469 let htlcs_count: u64 = Readable::read(r)?;
470 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
471 for _ in 0..htlcs_count {
472 let htlc = Readable::read(r)?;
475 if let Some(_) = per_htlc.insert(txid, htlcs) {
476 return Err(DecodeError::InvalidValue);
479 RemoteCommitmentTransaction {
480 remote_delayed_payment_base_key,
481 remote_htlc_base_key,
486 Ok(remote_commitment_transaction)
490 /// When ChannelMonitor discovers an onchain outpoint being a step of a channel and that it needs
491 /// to generate a tx to push channel state forward, we cache outpoint-solving tx material to build
492 /// a new bumped one in case of lenghty confirmation delay
493 #[derive(Clone, PartialEq)]
494 pub(crate) enum InputMaterial {
496 per_commitment_point: PublicKey,
497 remote_delayed_payment_base_key: PublicKey,
498 remote_htlc_base_key: PublicKey,
499 per_commitment_key: SecretKey,
500 input_descriptor: InputDescriptors,
502 htlc: Option<HTLCOutputInCommitment>,
503 on_remote_tx_csv: u16,
506 per_commitment_point: PublicKey,
507 remote_delayed_payment_base_key: PublicKey,
508 remote_htlc_base_key: PublicKey,
509 preimage: Option<PaymentPreimage>,
510 htlc: HTLCOutputInCommitment
513 preimage: Option<PaymentPreimage>,
517 funding_redeemscript: Script,
521 impl Writeable for InputMaterial {
522 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
524 &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} => {
525 writer.write_all(&[0; 1])?;
526 per_commitment_point.write(writer)?;
527 remote_delayed_payment_base_key.write(writer)?;
528 remote_htlc_base_key.write(writer)?;
529 writer.write_all(&per_commitment_key[..])?;
530 input_descriptor.write(writer)?;
531 writer.write_all(&byte_utils::be64_to_array(*amount))?;
533 on_remote_tx_csv.write(writer)?;
535 &InputMaterial::RemoteHTLC { ref per_commitment_point, ref remote_delayed_payment_base_key, ref remote_htlc_base_key, ref preimage, ref htlc} => {
536 writer.write_all(&[1; 1])?;
537 per_commitment_point.write(writer)?;
538 remote_delayed_payment_base_key.write(writer)?;
539 remote_htlc_base_key.write(writer)?;
540 preimage.write(writer)?;
543 &InputMaterial::LocalHTLC { ref preimage, ref amount } => {
544 writer.write_all(&[2; 1])?;
545 preimage.write(writer)?;
546 writer.write_all(&byte_utils::be64_to_array(*amount))?;
548 &InputMaterial::Funding { ref funding_redeemscript } => {
549 writer.write_all(&[3; 1])?;
550 funding_redeemscript.write(writer)?;
557 impl Readable for InputMaterial {
558 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
559 let input_material = match <u8 as Readable>::read(reader)? {
561 let per_commitment_point = Readable::read(reader)?;
562 let remote_delayed_payment_base_key = Readable::read(reader)?;
563 let remote_htlc_base_key = Readable::read(reader)?;
564 let per_commitment_key = Readable::read(reader)?;
565 let input_descriptor = Readable::read(reader)?;
566 let amount = Readable::read(reader)?;
567 let htlc = Readable::read(reader)?;
568 let on_remote_tx_csv = Readable::read(reader)?;
569 InputMaterial::Revoked {
570 per_commitment_point,
571 remote_delayed_payment_base_key,
572 remote_htlc_base_key,
581 let per_commitment_point = Readable::read(reader)?;
582 let remote_delayed_payment_base_key = Readable::read(reader)?;
583 let remote_htlc_base_key = Readable::read(reader)?;
584 let preimage = Readable::read(reader)?;
585 let htlc = Readable::read(reader)?;
586 InputMaterial::RemoteHTLC {
587 per_commitment_point,
588 remote_delayed_payment_base_key,
589 remote_htlc_base_key,
595 let preimage = Readable::read(reader)?;
596 let amount = Readable::read(reader)?;
597 InputMaterial::LocalHTLC {
603 InputMaterial::Funding {
604 funding_redeemscript: Readable::read(reader)?,
607 _ => return Err(DecodeError::InvalidValue),
613 /// ClaimRequest is a descriptor structure to communicate between detection
614 /// and reaction module. They are generated by ChannelMonitor while parsing
615 /// onchain txn leaked from a channel and handed over to OnchainTxHandler which
616 /// is responsible for opportunistic aggregation, selecting and enforcing
617 /// bumping logic, building and signing transactions.
618 pub(crate) struct ClaimRequest {
619 // Block height before which claiming is exclusive to one party,
620 // after reaching it, claiming may be contentious.
621 pub(crate) absolute_timelock: u32,
622 // Timeout tx must have nLocktime set which means aggregating multiple
623 // ones must take the higher nLocktime among them to satisfy all of them.
624 // Sadly it has few pitfalls, a) it takes longuer to get fund back b) CLTV_DELTA
625 // of a sooner-HTLC could be swallowed by the highest nLocktime of the HTLC set.
626 // Do simplify we mark them as non-aggregable.
627 pub(crate) aggregable: bool,
628 // Basic bitcoin outpoint (txid, vout)
629 pub(crate) outpoint: BitcoinOutPoint,
630 // Following outpoint type, set of data needed to generate transaction digest
631 // and satisfy witness program.
632 pub(crate) witness_data: InputMaterial
635 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
636 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
637 #[derive(Clone, PartialEq)]
639 /// HTLC output getting solved by a timeout, at maturation we pass upstream payment source information to solve
640 /// inbound HTLC in backward channel. Note, in case of preimage, we pass info to upstream without delay as we can
641 /// only win from it, so it's never an OnchainEvent
643 htlc_update: (HTLCSource, PaymentHash),
646 descriptor: SpendableOutputDescriptor,
650 const SERIALIZATION_VERSION: u8 = 1;
651 const MIN_SERIALIZATION_VERSION: u8 = 1;
653 #[cfg_attr(test, derive(PartialEq))]
655 pub(super) enum ChannelMonitorUpdateStep {
656 LatestLocalCommitmentTXInfo {
657 commitment_tx: LocalCommitmentTransaction,
658 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
660 LatestRemoteCommitmentTXInfo {
661 unsigned_commitment_tx: Transaction, // TODO: We should actually only need the txid here
662 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
663 commitment_number: u64,
664 their_revocation_point: PublicKey,
667 payment_preimage: PaymentPreimage,
673 /// Used to indicate that the no future updates will occur, and likely that the latest local
674 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
676 /// If set to false, we shouldn't broadcast the latest local commitment transaction as we
677 /// think we've fallen behind!
678 should_broadcast: bool,
682 impl Writeable for ChannelMonitorUpdateStep {
683 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
685 &ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { ref commitment_tx, ref htlc_outputs } => {
687 commitment_tx.write(w)?;
688 (htlc_outputs.len() as u64).write(w)?;
689 for &(ref output, ref signature, ref source) in htlc_outputs.iter() {
695 &ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { ref unsigned_commitment_tx, ref htlc_outputs, ref commitment_number, ref their_revocation_point } => {
697 unsigned_commitment_tx.write(w)?;
698 commitment_number.write(w)?;
699 their_revocation_point.write(w)?;
700 (htlc_outputs.len() as u64).write(w)?;
701 for &(ref output, ref source) in htlc_outputs.iter() {
703 source.as_ref().map(|b| b.as_ref()).write(w)?;
706 &ChannelMonitorUpdateStep::PaymentPreimage { ref payment_preimage } => {
708 payment_preimage.write(w)?;
710 &ChannelMonitorUpdateStep::CommitmentSecret { ref idx, ref secret } => {
715 &ChannelMonitorUpdateStep::ChannelForceClosed { ref should_broadcast } => {
717 should_broadcast.write(w)?;
723 impl Readable for ChannelMonitorUpdateStep {
724 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
725 match Readable::read(r)? {
727 Ok(ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo {
728 commitment_tx: Readable::read(r)?,
730 let len: u64 = Readable::read(r)?;
731 let mut res = Vec::new();
733 res.push((Readable::read(r)?, Readable::read(r)?, Readable::read(r)?));
740 Ok(ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo {
741 unsigned_commitment_tx: Readable::read(r)?,
742 commitment_number: Readable::read(r)?,
743 their_revocation_point: Readable::read(r)?,
745 let len: u64 = Readable::read(r)?;
746 let mut res = Vec::new();
748 res.push((Readable::read(r)?, <Option<HTLCSource> as Readable>::read(r)?.map(|o| Box::new(o))));
755 Ok(ChannelMonitorUpdateStep::PaymentPreimage {
756 payment_preimage: Readable::read(r)?,
760 Ok(ChannelMonitorUpdateStep::CommitmentSecret {
761 idx: Readable::read(r)?,
762 secret: Readable::read(r)?,
766 Ok(ChannelMonitorUpdateStep::ChannelForceClosed {
767 should_broadcast: Readable::read(r)?
770 _ => Err(DecodeError::InvalidValue),
775 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
776 /// on-chain transactions to ensure no loss of funds occurs.
778 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
779 /// information and are actively monitoring the chain.
781 /// Pending Events or updated HTLCs which have not yet been read out by
782 /// get_and_clear_pending_htlcs_updated or get_and_clear_pending_events are serialized to disk and
783 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
784 /// gotten are fully handled before re-serializing the new state.
785 pub struct ChannelMonitor<ChanSigner: ChannelKeys> {
786 latest_update_id: u64,
787 commitment_transaction_number_obscure_factor: u64,
789 destination_script: Script,
790 broadcasted_local_revokable_script: Option<(Script, PublicKey, PublicKey)>,
791 remote_payment_script: Script,
792 shutdown_script: Script,
795 funding_info: (OutPoint, Script),
796 current_remote_commitment_txid: Option<Txid>,
797 prev_remote_commitment_txid: Option<Txid>,
799 remote_tx_cache: RemoteCommitmentTransaction,
800 funding_redeemscript: Script,
801 channel_value_satoshis: u64,
802 // first is the idx of the first of the two revocation points
803 their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
805 on_local_tx_csv: u16,
807 commitment_secrets: CounterpartyCommitmentSecrets,
808 remote_claimable_outpoints: HashMap<Txid, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
809 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
810 /// Nor can we figure out their commitment numbers without the commitment transaction they are
811 /// spending. Thus, in order to claim them via revocation key, we track all the remote
812 /// commitment transactions which we find on-chain, mapping them to the commitment number which
813 /// can be used to derive the revocation key and claim the transactions.
814 remote_commitment_txn_on_chain: HashMap<Txid, (u64, Vec<Script>)>,
815 /// Cache used to make pruning of payment_preimages faster.
816 /// Maps payment_hash values to commitment numbers for remote transactions for non-revoked
817 /// remote transactions (ie should remain pretty small).
818 /// Serialized to disk but should generally not be sent to Watchtowers.
819 remote_hash_commitment_number: HashMap<PaymentHash, u64>,
821 // We store two local commitment transactions to avoid any race conditions where we may update
822 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
823 // various monitors for one channel being out of sync, and us broadcasting a local
824 // transaction for which we have deleted claim information on some watchtowers.
825 prev_local_signed_commitment_tx: Option<LocalSignedTx>,
826 current_local_commitment_tx: LocalSignedTx,
828 // Used just for ChannelManager to make sure it has the latest channel data during
830 current_remote_commitment_number: u64,
831 // Used just for ChannelManager to make sure it has the latest channel data during
833 current_local_commitment_number: u64,
835 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
837 pending_htlcs_updated: Vec<HTLCUpdate>,
838 pending_events: Vec<events::Event>,
840 // Used to track onchain events, i.e transactions parts of channels confirmed on chain, on which
841 // we have to take actions once they reach enough confs. Key is a block height timer, i.e we enforce
842 // actions when we receive a block with given height. Actions depend on OnchainEvent type.
843 onchain_events_waiting_threshold_conf: HashMap<u32, Vec<OnchainEvent>>,
845 // If we get serialized out and re-read, we need to make sure that the chain monitoring
846 // interface knows about the TXOs that we want to be notified of spends of. We could probably
847 // be smart and derive them from the above storage fields, but its much simpler and more
848 // Obviously Correct (tm) if we just keep track of them explicitly.
849 outputs_to_watch: HashMap<Txid, Vec<Script>>,
852 pub onchain_tx_handler: OnchainTxHandler<ChanSigner>,
854 onchain_tx_handler: OnchainTxHandler<ChanSigner>,
856 // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
857 // channel has been force-closed. After this is set, no further local commitment transaction
858 // updates may occur, and we panic!() if one is provided.
859 lockdown_from_offchain: bool,
861 // Set once we've signed a local commitment transaction and handed it over to our
862 // OnchainTxHandler. After this is set, no future updates to our local commitment transactions
863 // may occur, and we fail any such monitor updates.
864 local_tx_signed: bool,
866 // We simply modify last_block_hash in Channel's block_connected so that serialization is
867 // consistent but hopefully the users' copy handles block_connected in a consistent way.
868 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
869 // their last_block_hash from its state and not based on updated copies that didn't run through
870 // the full block_connected).
871 pub(crate) last_block_hash: BlockHash,
872 secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
875 /// Simple trait indicating ability to track a set of ChannelMonitors and multiplex events between
876 /// them. Generally should be implemented by keeping a local SimpleManyChannelMonitor and passing
877 /// events to it, while also taking any add/update_monitor events and passing them to some remote
880 /// In general, you must always have at least one local copy in memory, which must never fail to
881 /// update (as it is responsible for broadcasting the latest state in case the channel is closed),
882 /// and then persist it to various on-disk locations. If, for some reason, the in-memory copy fails
883 /// to update (eg out-of-memory or some other condition), you must immediately shut down without
884 /// taking any further action such as writing the current state to disk. This should likely be
885 /// accomplished via panic!() or abort().
887 /// Note that any updates to a channel's monitor *must* be applied to each instance of the
888 /// channel's monitor everywhere (including remote watchtowers) *before* this function returns. If
889 /// an update occurs and a remote watchtower is left with old state, it may broadcast transactions
890 /// which we have revoked, allowing our counterparty to claim all funds in the channel!
892 /// User needs to notify implementors of ManyChannelMonitor when a new block is connected or
893 /// disconnected using their `block_connected` and `block_disconnected` methods. However, rather
894 /// than calling these methods directly, the user should register implementors as listeners to the
895 /// BlockNotifier and call the BlockNotifier's `block_(dis)connected` methods, which will notify
896 /// all registered listeners in one go.
897 pub trait ManyChannelMonitor: Send + Sync {
898 /// The concrete type which signs for transactions and provides access to our channel public
900 type Keys: ChannelKeys;
902 /// Adds a monitor for the given `funding_txo`.
904 /// Implementations must ensure that `monitor` receives block_connected calls for blocks with
905 /// the funding transaction or any spends of it, as well as any spends of outputs returned by
906 /// get_outputs_to_watch. Not doing so may result in LOST FUNDS.
907 fn add_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor<Self::Keys>) -> Result<(), ChannelMonitorUpdateErr>;
909 /// Updates a monitor for the given `funding_txo`.
910 fn update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr>;
912 /// Used by ChannelManager to get list of HTLC resolved onchain and which needed to be updated
913 /// with success or failure.
915 /// You should probably just call through to
916 /// ChannelMonitor::get_and_clear_pending_htlcs_updated() for each ChannelMonitor and return
918 fn get_and_clear_pending_htlcs_updated(&self) -> Vec<HTLCUpdate>;
921 #[cfg(any(test, feature = "fuzztarget"))]
922 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
923 /// underlying object
924 impl<ChanSigner: ChannelKeys> PartialEq for ChannelMonitor<ChanSigner> {
925 fn eq(&self, other: &Self) -> bool {
926 if self.latest_update_id != other.latest_update_id ||
927 self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
928 self.destination_script != other.destination_script ||
929 self.broadcasted_local_revokable_script != other.broadcasted_local_revokable_script ||
930 self.remote_payment_script != other.remote_payment_script ||
931 self.keys.pubkeys() != other.keys.pubkeys() ||
932 self.funding_info != other.funding_info ||
933 self.current_remote_commitment_txid != other.current_remote_commitment_txid ||
934 self.prev_remote_commitment_txid != other.prev_remote_commitment_txid ||
935 self.remote_tx_cache != other.remote_tx_cache ||
936 self.funding_redeemscript != other.funding_redeemscript ||
937 self.channel_value_satoshis != other.channel_value_satoshis ||
938 self.their_cur_revocation_points != other.their_cur_revocation_points ||
939 self.on_local_tx_csv != other.on_local_tx_csv ||
940 self.commitment_secrets != other.commitment_secrets ||
941 self.remote_claimable_outpoints != other.remote_claimable_outpoints ||
942 self.remote_commitment_txn_on_chain != other.remote_commitment_txn_on_chain ||
943 self.remote_hash_commitment_number != other.remote_hash_commitment_number ||
944 self.prev_local_signed_commitment_tx != other.prev_local_signed_commitment_tx ||
945 self.current_remote_commitment_number != other.current_remote_commitment_number ||
946 self.current_local_commitment_number != other.current_local_commitment_number ||
947 self.current_local_commitment_tx != other.current_local_commitment_tx ||
948 self.payment_preimages != other.payment_preimages ||
949 self.pending_htlcs_updated != other.pending_htlcs_updated ||
950 self.pending_events.len() != other.pending_events.len() || // We trust events to round-trip properly
951 self.onchain_events_waiting_threshold_conf != other.onchain_events_waiting_threshold_conf ||
952 self.outputs_to_watch != other.outputs_to_watch ||
953 self.lockdown_from_offchain != other.lockdown_from_offchain ||
954 self.local_tx_signed != other.local_tx_signed
963 impl<ChanSigner: ChannelKeys + Writeable> ChannelMonitor<ChanSigner> {
964 /// Writes this monitor into the given writer, suitable for writing to disk.
966 /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
967 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
968 /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
969 /// returned block hash and the the current chain and then reconnecting blocks to get to the
970 /// best chain) upon deserializing the object!
971 pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
972 //TODO: We still write out all the serialization here manually instead of using the fancy
973 //serialization framework we have, we should migrate things over to it.
974 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
975 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
977 self.latest_update_id.write(writer)?;
979 // Set in initial Channel-object creation, so should always be set by now:
980 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
982 self.destination_script.write(writer)?;
983 if let Some(ref broadcasted_local_revokable_script) = self.broadcasted_local_revokable_script {
984 writer.write_all(&[0; 1])?;
985 broadcasted_local_revokable_script.0.write(writer)?;
986 broadcasted_local_revokable_script.1.write(writer)?;
987 broadcasted_local_revokable_script.2.write(writer)?;
989 writer.write_all(&[1; 1])?;
992 self.remote_payment_script.write(writer)?;
993 self.shutdown_script.write(writer)?;
995 self.keys.write(writer)?;
996 writer.write_all(&self.funding_info.0.txid[..])?;
997 writer.write_all(&byte_utils::be16_to_array(self.funding_info.0.index))?;
998 self.funding_info.1.write(writer)?;
999 self.current_remote_commitment_txid.write(writer)?;
1000 self.prev_remote_commitment_txid.write(writer)?;
1002 self.remote_tx_cache.write(writer)?;
1003 self.funding_redeemscript.write(writer)?;
1004 self.channel_value_satoshis.write(writer)?;
1006 match self.their_cur_revocation_points {
1007 Some((idx, pubkey, second_option)) => {
1008 writer.write_all(&byte_utils::be48_to_array(idx))?;
1009 writer.write_all(&pubkey.serialize())?;
1010 match second_option {
1011 Some(second_pubkey) => {
1012 writer.write_all(&second_pubkey.serialize())?;
1015 writer.write_all(&[0; 33])?;
1020 writer.write_all(&byte_utils::be48_to_array(0))?;
1024 writer.write_all(&byte_utils::be16_to_array(self.on_local_tx_csv))?;
1026 self.commitment_secrets.write(writer)?;
1028 macro_rules! serialize_htlc_in_commitment {
1029 ($htlc_output: expr) => {
1030 writer.write_all(&[$htlc_output.offered as u8; 1])?;
1031 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
1032 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
1033 writer.write_all(&$htlc_output.payment_hash.0[..])?;
1034 $htlc_output.transaction_output_index.write(writer)?;
1038 writer.write_all(&byte_utils::be64_to_array(self.remote_claimable_outpoints.len() as u64))?;
1039 for (ref txid, ref htlc_infos) in self.remote_claimable_outpoints.iter() {
1040 writer.write_all(&txid[..])?;
1041 writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
1042 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
1043 serialize_htlc_in_commitment!(htlc_output);
1044 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
1048 writer.write_all(&byte_utils::be64_to_array(self.remote_commitment_txn_on_chain.len() as u64))?;
1049 for (ref txid, &(commitment_number, ref txouts)) in self.remote_commitment_txn_on_chain.iter() {
1050 writer.write_all(&txid[..])?;
1051 writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
1052 (txouts.len() as u64).write(writer)?;
1053 for script in txouts.iter() {
1054 script.write(writer)?;
1058 writer.write_all(&byte_utils::be64_to_array(self.remote_hash_commitment_number.len() as u64))?;
1059 for (ref payment_hash, commitment_number) in self.remote_hash_commitment_number.iter() {
1060 writer.write_all(&payment_hash.0[..])?;
1061 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
1064 macro_rules! serialize_local_tx {
1065 ($local_tx: expr) => {
1066 $local_tx.txid.write(writer)?;
1067 writer.write_all(&$local_tx.revocation_key.serialize())?;
1068 writer.write_all(&$local_tx.a_htlc_key.serialize())?;
1069 writer.write_all(&$local_tx.b_htlc_key.serialize())?;
1070 writer.write_all(&$local_tx.delayed_payment_key.serialize())?;
1071 writer.write_all(&$local_tx.per_commitment_point.serialize())?;
1073 writer.write_all(&byte_utils::be32_to_array($local_tx.feerate_per_kw))?;
1074 writer.write_all(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64))?;
1075 for &(ref htlc_output, ref sig, ref htlc_source) in $local_tx.htlc_outputs.iter() {
1076 serialize_htlc_in_commitment!(htlc_output);
1077 if let &Some(ref their_sig) = sig {
1079 writer.write_all(&their_sig.serialize_compact())?;
1083 htlc_source.write(writer)?;
1088 if let Some(ref prev_local_tx) = self.prev_local_signed_commitment_tx {
1089 writer.write_all(&[1; 1])?;
1090 serialize_local_tx!(prev_local_tx);
1092 writer.write_all(&[0; 1])?;
1095 serialize_local_tx!(self.current_local_commitment_tx);
1097 writer.write_all(&byte_utils::be48_to_array(self.current_remote_commitment_number))?;
1098 writer.write_all(&byte_utils::be48_to_array(self.current_local_commitment_number))?;
1100 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
1101 for payment_preimage in self.payment_preimages.values() {
1102 writer.write_all(&payment_preimage.0[..])?;
1105 writer.write_all(&byte_utils::be64_to_array(self.pending_htlcs_updated.len() as u64))?;
1106 for data in self.pending_htlcs_updated.iter() {
1107 data.write(writer)?;
1110 writer.write_all(&byte_utils::be64_to_array(self.pending_events.len() as u64))?;
1111 for event in self.pending_events.iter() {
1112 event.write(writer)?;
1115 self.last_block_hash.write(writer)?;
1117 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_waiting_threshold_conf.len() as u64))?;
1118 for (ref target, ref events) in self.onchain_events_waiting_threshold_conf.iter() {
1119 writer.write_all(&byte_utils::be32_to_array(**target))?;
1120 writer.write_all(&byte_utils::be64_to_array(events.len() as u64))?;
1121 for ev in events.iter() {
1123 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1125 htlc_update.0.write(writer)?;
1126 htlc_update.1.write(writer)?;
1128 OnchainEvent::MaturingOutput { ref descriptor } => {
1130 descriptor.write(writer)?;
1136 (self.outputs_to_watch.len() as u64).write(writer)?;
1137 for (txid, output_scripts) in self.outputs_to_watch.iter() {
1138 txid.write(writer)?;
1139 (output_scripts.len() as u64).write(writer)?;
1140 for script in output_scripts.iter() {
1141 script.write(writer)?;
1144 self.onchain_tx_handler.write(writer)?;
1146 self.lockdown_from_offchain.write(writer)?;
1147 self.local_tx_signed.write(writer)?;
1153 impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
1154 pub(super) fn new(keys: ChanSigner, shutdown_pubkey: &PublicKey,
1155 on_remote_tx_csv: u16, destination_script: &Script, funding_info: (OutPoint, Script),
1156 remote_htlc_base_key: &PublicKey, remote_delayed_payment_base_key: &PublicKey,
1157 on_local_tx_csv: u16, funding_redeemscript: Script, channel_value_satoshis: u64,
1158 commitment_transaction_number_obscure_factor: u64,
1159 initial_local_commitment_tx: LocalCommitmentTransaction) -> ChannelMonitor<ChanSigner> {
1161 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
1162 let our_channel_close_key_hash = WPubkeyHash::hash(&shutdown_pubkey.serialize());
1163 let shutdown_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
1164 let payment_key_hash = WPubkeyHash::hash(&keys.pubkeys().payment_point.serialize());
1165 let remote_payment_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_key_hash[..]).into_script();
1167 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() };
1169 let mut onchain_tx_handler = OnchainTxHandler::new(destination_script.clone(), keys.clone(), on_local_tx_csv);
1171 let local_tx_sequence = initial_local_commitment_tx.unsigned_tx.input[0].sequence as u64;
1172 let local_tx_locktime = initial_local_commitment_tx.unsigned_tx.lock_time as u64;
1173 let local_commitment_tx = LocalSignedTx {
1174 txid: initial_local_commitment_tx.txid(),
1175 revocation_key: initial_local_commitment_tx.local_keys.revocation_key,
1176 a_htlc_key: initial_local_commitment_tx.local_keys.a_htlc_key,
1177 b_htlc_key: initial_local_commitment_tx.local_keys.b_htlc_key,
1178 delayed_payment_key: initial_local_commitment_tx.local_keys.a_delayed_payment_key,
1179 per_commitment_point: initial_local_commitment_tx.local_keys.per_commitment_point,
1180 feerate_per_kw: initial_local_commitment_tx.feerate_per_kw,
1181 htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
1183 // Returning a monitor error before updating tracking points means in case of using
1184 // a concurrent watchtower implementation for same channel, if this one doesn't
1185 // reject update as we do, you MAY have the latest local valid commitment tx onchain
1186 // for which you want to spend outputs. We're NOT robust again this scenario right
1187 // now but we should consider it later.
1188 onchain_tx_handler.provide_latest_local_tx(initial_local_commitment_tx).unwrap();
1191 latest_update_id: 0,
1192 commitment_transaction_number_obscure_factor,
1194 destination_script: destination_script.clone(),
1195 broadcasted_local_revokable_script: None,
1196 remote_payment_script,
1201 current_remote_commitment_txid: None,
1202 prev_remote_commitment_txid: None,
1205 funding_redeemscript,
1206 channel_value_satoshis: channel_value_satoshis,
1207 their_cur_revocation_points: None,
1211 commitment_secrets: CounterpartyCommitmentSecrets::new(),
1212 remote_claimable_outpoints: HashMap::new(),
1213 remote_commitment_txn_on_chain: HashMap::new(),
1214 remote_hash_commitment_number: HashMap::new(),
1216 prev_local_signed_commitment_tx: None,
1217 current_local_commitment_tx: local_commitment_tx,
1218 current_remote_commitment_number: 1 << 48,
1219 current_local_commitment_number: 0xffff_ffff_ffff - ((((local_tx_sequence & 0xffffff) << 3*8) | (local_tx_locktime as u64 & 0xffffff)) ^ commitment_transaction_number_obscure_factor),
1221 payment_preimages: HashMap::new(),
1222 pending_htlcs_updated: Vec::new(),
1223 pending_events: Vec::new(),
1225 onchain_events_waiting_threshold_conf: HashMap::new(),
1226 outputs_to_watch: HashMap::new(),
1230 lockdown_from_offchain: false,
1231 local_tx_signed: false,
1233 last_block_hash: Default::default(),
1234 secp_ctx: Secp256k1::new(),
1238 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
1239 /// needed by local commitment transactions HTCLs nor by remote ones. Unless we haven't already seen remote
1240 /// commitment transaction's secret, they are de facto pruned (we can use revocation key).
1241 pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
1242 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
1243 return Err(MonitorUpdateError("Previous secret did not match new one"));
1246 // Prune HTLCs from the previous remote commitment tx so we don't generate failure/fulfill
1247 // events for now-revoked/fulfilled HTLCs.
1248 if let Some(txid) = self.prev_remote_commitment_txid.take() {
1249 for &mut (_, ref mut source) in self.remote_claimable_outpoints.get_mut(&txid).unwrap() {
1254 if !self.payment_preimages.is_empty() {
1255 let cur_local_signed_commitment_tx = &self.current_local_commitment_tx;
1256 let prev_local_signed_commitment_tx = self.prev_local_signed_commitment_tx.as_ref();
1257 let min_idx = self.get_min_seen_secret();
1258 let remote_hash_commitment_number = &mut self.remote_hash_commitment_number;
1260 self.payment_preimages.retain(|&k, _| {
1261 for &(ref htlc, _, _) in cur_local_signed_commitment_tx.htlc_outputs.iter() {
1262 if k == htlc.payment_hash {
1266 if let Some(prev_local_commitment_tx) = prev_local_signed_commitment_tx {
1267 for &(ref htlc, _, _) in prev_local_commitment_tx.htlc_outputs.iter() {
1268 if k == htlc.payment_hash {
1273 let contains = if let Some(cn) = remote_hash_commitment_number.get(&k) {
1280 remote_hash_commitment_number.remove(&k);
1289 /// Informs this monitor of the latest remote (ie non-broadcastable) commitment transaction.
1290 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
1291 /// possibly future revocation/preimage information) to claim outputs where possible.
1292 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
1293 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 {
1294 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
1295 // so that a remote monitor doesn't learn anything unless there is a malicious close.
1296 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
1298 for &(ref htlc, _) in &htlc_outputs {
1299 self.remote_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
1302 let new_txid = unsigned_commitment_tx.txid();
1303 log_trace!(logger, "Tracking new remote commitment transaction with txid {} at commitment number {} with {} HTLC outputs", new_txid, commitment_number, htlc_outputs.len());
1304 log_trace!(logger, "New potential remote commitment transaction: {}", encode::serialize_hex(unsigned_commitment_tx));
1305 self.prev_remote_commitment_txid = self.current_remote_commitment_txid.take();
1306 self.current_remote_commitment_txid = Some(new_txid);
1307 self.remote_claimable_outpoints.insert(new_txid, htlc_outputs.clone());
1308 self.current_remote_commitment_number = commitment_number;
1309 //TODO: Merge this into the other per-remote-transaction output storage stuff
1310 match self.their_cur_revocation_points {
1311 Some(old_points) => {
1312 if old_points.0 == commitment_number + 1 {
1313 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
1314 } else if old_points.0 == commitment_number + 2 {
1315 if let Some(old_second_point) = old_points.2 {
1316 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
1318 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1321 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1325 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1328 let mut htlcs = Vec::with_capacity(htlc_outputs.len());
1329 for htlc in htlc_outputs {
1330 if htlc.0.transaction_output_index.is_some() {
1334 self.remote_tx_cache.per_htlc.insert(new_txid, htlcs);
1337 /// Informs this monitor of the latest local (ie broadcastable) commitment transaction. The
1338 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
1339 /// is important that any clones of this channel monitor (including remote clones) by kept
1340 /// up-to-date as our local commitment transaction is updated.
1341 /// Panics if set_on_local_tx_csv has never been called.
1342 pub(super) fn provide_latest_local_commitment_tx_info(&mut self, commitment_tx: LocalCommitmentTransaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), MonitorUpdateError> {
1343 if self.local_tx_signed {
1344 return Err(MonitorUpdateError("A local commitment tx has already been signed, no new local commitment txn can be sent to our counterparty"));
1346 let txid = commitment_tx.txid();
1347 let sequence = commitment_tx.unsigned_tx.input[0].sequence as u64;
1348 let locktime = commitment_tx.unsigned_tx.lock_time as u64;
1349 let mut new_local_commitment_tx = LocalSignedTx {
1351 revocation_key: commitment_tx.local_keys.revocation_key,
1352 a_htlc_key: commitment_tx.local_keys.a_htlc_key,
1353 b_htlc_key: commitment_tx.local_keys.b_htlc_key,
1354 delayed_payment_key: commitment_tx.local_keys.a_delayed_payment_key,
1355 per_commitment_point: commitment_tx.local_keys.per_commitment_point,
1356 feerate_per_kw: commitment_tx.feerate_per_kw,
1357 htlc_outputs: htlc_outputs,
1359 // Returning a monitor error before updating tracking points means in case of using
1360 // a concurrent watchtower implementation for same channel, if this one doesn't
1361 // reject update as we do, you MAY have the latest local valid commitment tx onchain
1362 // for which you want to spend outputs. We're NOT robust again this scenario right
1363 // now but we should consider it later.
1364 if let Err(_) = self.onchain_tx_handler.provide_latest_local_tx(commitment_tx) {
1365 return Err(MonitorUpdateError("Local commitment signed has already been signed, no further update of LOCAL commitment transaction is allowed"));
1367 self.current_local_commitment_number = 0xffff_ffff_ffff - ((((sequence & 0xffffff) << 3*8) | (locktime as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
1368 mem::swap(&mut new_local_commitment_tx, &mut self.current_local_commitment_tx);
1369 self.prev_local_signed_commitment_tx = Some(new_local_commitment_tx);
1373 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
1374 /// commitment_tx_infos which contain the payment hash have been revoked.
1375 pub(super) fn provide_payment_preimage(&mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage) {
1376 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
1379 pub(super) fn broadcast_latest_local_commitment_txn<B: Deref, L: Deref>(&mut self, broadcaster: &B, logger: &L)
1380 where B::Target: BroadcasterInterface,
1383 for tx in self.get_latest_local_commitment_txn(logger).iter() {
1384 broadcaster.broadcast_transaction(tx);
1388 /// Used in Channel to cheat wrt the update_ids since it plays games, will be removed soon!
1389 pub(super) fn update_monitor_ooo<L: Deref>(&mut self, mut updates: ChannelMonitorUpdate, logger: &L) -> Result<(), MonitorUpdateError> where L::Target: Logger {
1390 for update in updates.updates.drain(..) {
1392 ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { commitment_tx, htlc_outputs } => {
1393 if self.lockdown_from_offchain { panic!(); }
1394 self.provide_latest_local_commitment_tx_info(commitment_tx, htlc_outputs)?
1396 ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
1397 self.provide_latest_remote_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point, logger),
1398 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
1399 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
1400 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
1401 self.provide_secret(idx, secret)?,
1402 ChannelMonitorUpdateStep::ChannelForceClosed { .. } => {},
1405 self.latest_update_id = updates.update_id;
1409 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
1412 /// panics if the given update is not the next update by update_id.
1413 pub fn update_monitor<B: Deref, L: Deref>(&mut self, mut updates: ChannelMonitorUpdate, broadcaster: &B, logger: &L) -> Result<(), MonitorUpdateError>
1414 where B::Target: BroadcasterInterface,
1417 if self.latest_update_id + 1 != updates.update_id {
1418 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
1420 for update in updates.updates.drain(..) {
1422 ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { commitment_tx, htlc_outputs } => {
1423 if self.lockdown_from_offchain { panic!(); }
1424 self.provide_latest_local_commitment_tx_info(commitment_tx, htlc_outputs)?
1426 ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
1427 self.provide_latest_remote_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point, logger),
1428 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
1429 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
1430 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
1431 self.provide_secret(idx, secret)?,
1432 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
1433 self.lockdown_from_offchain = true;
1434 if should_broadcast {
1435 self.broadcast_latest_local_commitment_txn(broadcaster, logger);
1437 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");
1442 self.latest_update_id = updates.update_id;
1446 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
1448 pub fn get_latest_update_id(&self) -> u64 {
1449 self.latest_update_id
1452 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
1453 pub fn get_funding_txo(&self) -> &(OutPoint, Script) {
1457 /// Gets a list of txids, with their output scripts (in the order they appear in the
1458 /// transaction), which we must learn about spends of via block_connected().
1459 pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<Script>> {
1460 &self.outputs_to_watch
1463 /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
1464 /// Generally useful when deserializing as during normal operation the return values of
1465 /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
1466 /// that the get_funding_txo outpoint and transaction must also be monitored for!).
1467 pub fn get_monitored_outpoints(&self) -> Vec<(Txid, u32, &Script)> {
1468 let mut res = Vec::with_capacity(self.remote_commitment_txn_on_chain.len() * 2);
1469 for (ref txid, &(_, ref outputs)) in self.remote_commitment_txn_on_chain.iter() {
1470 for (idx, output) in outputs.iter().enumerate() {
1471 res.push(((*txid).clone(), idx as u32, output));
1477 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1478 /// ChannelManager via ManyChannelMonitor::get_and_clear_pending_htlcs_updated().
1479 pub fn get_and_clear_pending_htlcs_updated(&mut self) -> Vec<HTLCUpdate> {
1480 let mut ret = Vec::new();
1481 mem::swap(&mut ret, &mut self.pending_htlcs_updated);
1485 /// Gets the list of pending events which were generated by previous actions, clearing the list
1488 /// This is called by ManyChannelMonitor::get_and_clear_pending_events() and is equivalent to
1489 /// EventsProvider::get_and_clear_pending_events() except that it requires &mut self as we do
1490 /// no internal locking in ChannelMonitors.
1491 pub fn get_and_clear_pending_events(&mut self) -> Vec<events::Event> {
1492 let mut ret = Vec::new();
1493 mem::swap(&mut ret, &mut self.pending_events);
1497 /// Can only fail if idx is < get_min_seen_secret
1498 pub(super) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
1499 self.commitment_secrets.get_secret(idx)
1502 pub(super) fn get_min_seen_secret(&self) -> u64 {
1503 self.commitment_secrets.get_min_seen_secret()
1506 pub(super) fn get_cur_remote_commitment_number(&self) -> u64 {
1507 self.current_remote_commitment_number
1510 pub(super) fn get_cur_local_commitment_number(&self) -> u64 {
1511 self.current_local_commitment_number
1514 /// Attempts to claim a remote commitment transaction's outputs using the revocation key and
1515 /// data in remote_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
1516 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
1517 /// HTLC-Success/HTLC-Timeout transactions.
1518 /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
1519 /// revoked remote commitment tx
1520 fn check_spend_remote_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) where L::Target: Logger {
1521 // Most secp and related errors trying to create keys means we have no hope of constructing
1522 // a spend transaction...so we return no transactions to broadcast
1523 let mut claimable_outpoints = Vec::new();
1524 let mut watch_outputs = Vec::new();
1526 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1527 let per_commitment_option = self.remote_claimable_outpoints.get(&commitment_txid);
1529 macro_rules! ignore_error {
1530 ( $thing : expr ) => {
1533 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs))
1538 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);
1539 if commitment_number >= self.get_min_seen_secret() {
1540 let secret = self.get_secret(commitment_number).unwrap();
1541 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1542 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1543 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.keys.pubkeys().revocation_basepoint));
1544 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));
1546 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.remote_tx_cache.on_remote_tx_csv, &delayed_key);
1547 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1549 // First, process non-htlc outputs (to_local & to_remote)
1550 for (idx, outp) in tx.output.iter().enumerate() {
1551 if outp.script_pubkey == revokeable_p2wsh {
1552 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};
1553 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});
1557 // Then, try to find revoked htlc outputs
1558 if let Some(ref per_commitment_data) = per_commitment_option {
1559 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1560 if let Some(transaction_output_index) = htlc.transaction_output_index {
1561 if transaction_output_index as usize >= tx.output.len() ||
1562 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1563 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1565 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};
1566 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable: true, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1571 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
1572 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
1573 // We're definitely a remote commitment transaction!
1574 log_trace!(logger, "Got broadcast of revoked remote commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
1575 watch_outputs.append(&mut tx.output.clone());
1576 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1578 macro_rules! check_htlc_fails {
1579 ($txid: expr, $commitment_tx: expr) => {
1580 if let Some(ref outpoints) = self.remote_claimable_outpoints.get($txid) {
1581 for &(ref htlc, ref source_option) in outpoints.iter() {
1582 if let &Some(ref source) = source_option {
1583 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), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1584 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1585 hash_map::Entry::Occupied(mut entry) => {
1586 let e = entry.get_mut();
1587 e.retain(|ref event| {
1589 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1590 return htlc_update.0 != **source
1595 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1597 hash_map::Entry::Vacant(entry) => {
1598 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1606 if let Some(ref txid) = self.current_remote_commitment_txid {
1607 check_htlc_fails!(txid, "current");
1609 if let Some(ref txid) = self.prev_remote_commitment_txid {
1610 check_htlc_fails!(txid, "remote");
1612 // No need to check local commitment txn, symmetric HTLCSource must be present as per-htlc data on remote commitment tx
1614 } else if let Some(per_commitment_data) = per_commitment_option {
1615 // While this isn't useful yet, there is a potential race where if a counterparty
1616 // revokes a state at the same time as the commitment transaction for that state is
1617 // confirmed, and the watchtower receives the block before the user, the user could
1618 // upload a new ChannelMonitor with the revocation secret but the watchtower has
1619 // already processed the block, resulting in the remote_commitment_txn_on_chain entry
1620 // not being generated by the above conditional. Thus, to be safe, we go ahead and
1622 watch_outputs.append(&mut tx.output.clone());
1623 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1625 log_trace!(logger, "Got broadcast of non-revoked remote commitment transaction {}", commitment_txid);
1627 macro_rules! check_htlc_fails {
1628 ($txid: expr, $commitment_tx: expr, $id: tt) => {
1629 if let Some(ref latest_outpoints) = self.remote_claimable_outpoints.get($txid) {
1630 $id: for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1631 if let &Some(ref source) = source_option {
1632 // Check if the HTLC is present in the commitment transaction that was
1633 // broadcast, but not if it was below the dust limit, which we should
1634 // fail backwards immediately as there is no way for us to learn the
1635 // payment_preimage.
1636 // Note that if the dust limit were allowed to change between
1637 // commitment transactions we'd want to be check whether *any*
1638 // broadcastable commitment transaction has the HTLC in it, but it
1639 // cannot currently change after channel initialization, so we don't
1641 for &(ref broadcast_htlc, ref broadcast_source) in per_commitment_data.iter() {
1642 if broadcast_htlc.transaction_output_index.is_some() && Some(source) == broadcast_source.as_ref() {
1646 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);
1647 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1648 hash_map::Entry::Occupied(mut entry) => {
1649 let e = entry.get_mut();
1650 e.retain(|ref event| {
1652 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1653 return htlc_update.0 != **source
1658 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1660 hash_map::Entry::Vacant(entry) => {
1661 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1669 if let Some(ref txid) = self.current_remote_commitment_txid {
1670 check_htlc_fails!(txid, "current", 'current_loop);
1672 if let Some(ref txid) = self.prev_remote_commitment_txid {
1673 check_htlc_fails!(txid, "previous", 'prev_loop);
1676 if let Some(revocation_points) = self.their_cur_revocation_points {
1677 let revocation_point_option =
1678 if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1679 else if let Some(point) = revocation_points.2.as_ref() {
1680 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1682 if let Some(revocation_point) = revocation_point_option {
1683 self.remote_payment_script = {
1684 // Note that the Network here is ignored as we immediately drop the address for the
1685 // script_pubkey version
1686 let payment_hash160 = WPubkeyHash::hash(&self.keys.pubkeys().payment_point.serialize());
1687 Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_hash160[..]).into_script()
1690 // Then, try to find htlc outputs
1691 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1692 if let Some(transaction_output_index) = htlc.transaction_output_index {
1693 if transaction_output_index as usize >= tx.output.len() ||
1694 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1695 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1697 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
1698 let aggregable = if !htlc.offered { false } else { true };
1699 if preimage.is_some() || !htlc.offered {
1700 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() };
1701 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1708 (claimable_outpoints, (commitment_txid, watch_outputs))
1711 /// Attempts to claim a remote HTLC-Success/HTLC-Timeout's outputs using the revocation key
1712 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 {
1713 let htlc_txid = tx.txid();
1714 if tx.input.len() != 1 || tx.output.len() != 1 || tx.input[0].witness.len() != 5 {
1715 return (Vec::new(), None)
1718 macro_rules! ignore_error {
1719 ( $thing : expr ) => {
1722 Err(_) => return (Vec::new(), None)
1727 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
1728 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1729 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1731 log_trace!(logger, "Remote HTLC broadcast {}:{}", htlc_txid, 0);
1732 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 };
1733 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 });
1734 (claimable_outpoints, Some((htlc_txid, tx.output.clone())))
1737 fn broadcast_by_local_state(&self, commitment_tx: &Transaction, local_tx: &LocalSignedTx) -> (Vec<ClaimRequest>, Vec<TxOut>, Option<(Script, PublicKey, PublicKey)>) {
1738 let mut claim_requests = Vec::with_capacity(local_tx.htlc_outputs.len());
1739 let mut watch_outputs = Vec::with_capacity(local_tx.htlc_outputs.len());
1741 let redeemscript = chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.on_local_tx_csv, &local_tx.delayed_payment_key);
1742 let broadcasted_local_revokable_script = Some((redeemscript.to_v0_p2wsh(), local_tx.per_commitment_point.clone(), local_tx.revocation_key.clone()));
1744 for &(ref htlc, _, _) in local_tx.htlc_outputs.iter() {
1745 if let Some(transaction_output_index) = htlc.transaction_output_index {
1746 claim_requests.push(ClaimRequest { absolute_timelock: ::std::u32::MAX, aggregable: false, outpoint: BitcoinOutPoint { txid: local_tx.txid, vout: transaction_output_index as u32 },
1747 witness_data: InputMaterial::LocalHTLC {
1748 preimage: if !htlc.offered {
1749 if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1750 Some(preimage.clone())
1752 // We can't build an HTLC-Success transaction without the preimage
1756 amount: htlc.amount_msat,
1758 watch_outputs.push(commitment_tx.output[transaction_output_index as usize].clone());
1762 (claim_requests, watch_outputs, broadcasted_local_revokable_script)
1765 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1766 /// revoked using data in local_claimable_outpoints.
1767 /// Should not be used if check_spend_revoked_transaction succeeds.
1768 fn check_spend_local_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) where L::Target: Logger {
1769 let commitment_txid = tx.txid();
1770 let mut claim_requests = Vec::new();
1771 let mut watch_outputs = Vec::new();
1773 macro_rules! wait_threshold_conf {
1774 ($height: expr, $source: expr, $commitment_tx: expr, $payment_hash: expr) => {
1775 log_trace!(logger, "Failing HTLC with payment_hash {} from {} local commitment tx due to broadcast of transaction, waiting confirmation (at height{})", log_bytes!($payment_hash.0), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1776 match self.onchain_events_waiting_threshold_conf.entry($height + ANTI_REORG_DELAY - 1) {
1777 hash_map::Entry::Occupied(mut entry) => {
1778 let e = entry.get_mut();
1779 e.retain(|ref event| {
1781 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1782 return htlc_update.0 != $source
1787 e.push(OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)});
1789 hash_map::Entry::Vacant(entry) => {
1790 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)}]);
1796 macro_rules! append_onchain_update {
1797 ($updates: expr) => {
1798 claim_requests = $updates.0;
1799 watch_outputs.append(&mut $updates.1);
1800 self.broadcasted_local_revokable_script = $updates.2;
1804 // HTLCs set may differ between last and previous local commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
1805 let mut is_local_tx = false;
1807 if self.current_local_commitment_tx.txid == commitment_txid {
1809 log_trace!(logger, "Got latest local commitment tx broadcast, searching for available HTLCs to claim");
1810 let mut res = self.broadcast_by_local_state(tx, &self.current_local_commitment_tx);
1811 append_onchain_update!(res);
1812 } else if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1813 if local_tx.txid == commitment_txid {
1815 log_trace!(logger, "Got previous local commitment tx broadcast, searching for available HTLCs to claim");
1816 let mut res = self.broadcast_by_local_state(tx, local_tx);
1817 append_onchain_update!(res);
1821 macro_rules! fail_dust_htlcs_after_threshold_conf {
1822 ($local_tx: expr) => {
1823 for &(ref htlc, _, ref source) in &$local_tx.htlc_outputs {
1824 if htlc.transaction_output_index.is_none() {
1825 if let &Some(ref source) = source {
1826 wait_threshold_conf!(height, source.clone(), "lastest", htlc.payment_hash.clone());
1834 fail_dust_htlcs_after_threshold_conf!(self.current_local_commitment_tx);
1835 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1836 fail_dust_htlcs_after_threshold_conf!(local_tx);
1840 (claim_requests, (commitment_txid, watch_outputs))
1843 /// Used by ChannelManager deserialization to broadcast the latest local state if its copy of
1844 /// the Channel was out-of-date. You may use it to get a broadcastable local toxic tx in case of
1845 /// fallen-behind, i.e when receiving a channel_reestablish with a proof that our remote side knows
1846 /// a higher revocation secret than the local commitment number we are aware of. Broadcasting these
1847 /// transactions are UNSAFE, as they allow remote side to punish you. Nevertheless you may want to
1848 /// broadcast them if remote don't close channel with his higher commitment transaction after a
1849 /// substantial amount of time (a month or even a year) to get back funds. Best may be to contact
1850 /// out-of-band the other node operator to coordinate with him if option is available to you.
1851 /// In any-case, choice is up to the user.
1852 pub fn get_latest_local_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1853 log_trace!(logger, "Getting signed latest local commitment transaction!");
1854 self.local_tx_signed = true;
1855 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_local_tx(&self.funding_redeemscript) {
1856 let txid = commitment_tx.txid();
1857 let mut res = vec![commitment_tx];
1858 for htlc in self.current_local_commitment_tx.htlc_outputs.iter() {
1859 if let Some(vout) = htlc.0.transaction_output_index {
1860 let preimage = if !htlc.0.offered {
1861 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1862 // We can't build an HTLC-Success transaction without the preimage
1866 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
1867 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1872 // 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.
1873 // The data will be re-generated and tracked in check_spend_local_transaction if we get a confirmation.
1879 /// Unsafe test-only version of get_latest_local_commitment_txn used by our test framework
1880 /// to bypass LocalCommitmentTransaction state update lockdown after signature and generate
1881 /// revoked commitment transaction.
1883 pub fn unsafe_get_latest_local_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1884 log_trace!(logger, "Getting signed copy of latest local commitment transaction!");
1885 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_copy_local_tx(&self.funding_redeemscript) {
1886 let txid = commitment_tx.txid();
1887 let mut res = vec![commitment_tx];
1888 for htlc in self.current_local_commitment_tx.htlc_outputs.iter() {
1889 if let Some(vout) = htlc.0.transaction_output_index {
1890 let preimage = if !htlc.0.offered {
1891 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1892 // We can't build an HTLC-Success transaction without the preimage
1896 if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
1897 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1907 /// Called by SimpleManyChannelMonitor::block_connected, which implements
1908 /// ChainListener::block_connected.
1909 /// Eventually this should be pub and, roughly, implement ChainListener, however this requires
1910 /// &mut self, as well as returns new spendable outputs and outpoints to watch for spending of
1912 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>)>
1913 where B::Target: BroadcasterInterface,
1914 F::Target: FeeEstimator,
1917 for &(_, tx) in txn_matched {
1918 let mut output_val = 0;
1919 for out in tx.output.iter() {
1920 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1921 output_val += out.value;
1922 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1926 let block_hash = header.bitcoin_hash();
1927 log_trace!(logger, "Block {} at height {} connected with {} txn matched", block_hash, height, txn_matched.len());
1929 let mut watch_outputs = Vec::new();
1930 let mut claimable_outpoints = Vec::new();
1931 for &(_, tx) in txn_matched {
1932 if tx.input.len() == 1 {
1933 // Assuming our keys were not leaked (in which case we're screwed no matter what),
1934 // commitment transactions and HTLC transactions will all only ever have one input,
1935 // which is an easy way to filter out any potential non-matching txn for lazy
1937 let prevout = &tx.input[0].previous_output;
1938 if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
1939 if (tx.input[0].sequence >> 8*3) as u8 == 0x80 && (tx.lock_time >> 8*3) as u8 == 0x20 {
1940 let (mut new_outpoints, new_outputs) = self.check_spend_remote_transaction(&tx, height, &logger);
1941 if !new_outputs.1.is_empty() {
1942 watch_outputs.push(new_outputs);
1944 if new_outpoints.is_empty() {
1945 let (mut new_outpoints, new_outputs) = self.check_spend_local_transaction(&tx, height, &logger);
1946 if !new_outputs.1.is_empty() {
1947 watch_outputs.push(new_outputs);
1949 claimable_outpoints.append(&mut new_outpoints);
1951 claimable_outpoints.append(&mut new_outpoints);
1954 if let Some(&(commitment_number, _)) = self.remote_commitment_txn_on_chain.get(&prevout.txid) {
1955 let (mut new_outpoints, new_outputs_option) = self.check_spend_remote_htlc(&tx, commitment_number, height, &logger);
1956 claimable_outpoints.append(&mut new_outpoints);
1957 if let Some(new_outputs) = new_outputs_option {
1958 watch_outputs.push(new_outputs);
1963 // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
1964 // can also be resolved in a few other ways which can have more than one output. Thus,
1965 // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
1966 self.is_resolving_htlc_output(&tx, height, &logger);
1968 self.is_paying_spendable_output(&tx, height, &logger);
1970 let should_broadcast = self.would_broadcast_at_height(height, &logger);
1971 if should_broadcast {
1972 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() }});
1974 if should_broadcast {
1975 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_local_tx(&self.funding_redeemscript) {
1976 let (mut new_outpoints, new_outputs, _) = self.broadcast_by_local_state(&commitment_tx, &self.current_local_commitment_tx);
1977 if !new_outputs.is_empty() {
1978 watch_outputs.push((self.current_local_commitment_tx.txid.clone(), new_outputs));
1980 claimable_outpoints.append(&mut new_outpoints);
1983 if let Some(events) = self.onchain_events_waiting_threshold_conf.remove(&height) {
1986 OnchainEvent::HTLCUpdate { htlc_update } => {
1987 log_trace!(logger, "HTLC {} failure update has got enough confirmations to be passed upstream", log_bytes!((htlc_update.1).0));
1988 self.pending_htlcs_updated.push(HTLCUpdate {
1989 payment_hash: htlc_update.1,
1990 payment_preimage: None,
1991 source: htlc_update.0,
1994 OnchainEvent::MaturingOutput { descriptor } => {
1995 log_trace!(logger, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
1996 self.pending_events.push(events::Event::SpendableOutputs {
1997 outputs: vec![descriptor]
2003 self.onchain_tx_handler.block_connected(txn_matched, claimable_outpoints, height, &*broadcaster, &*fee_estimator, &*logger);
2005 self.last_block_hash = block_hash;
2006 for &(ref txid, ref output_scripts) in watch_outputs.iter() {
2007 self.outputs_to_watch.insert(txid.clone(), output_scripts.iter().map(|o| o.script_pubkey.clone()).collect());
2013 fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, height: u32, broadcaster: B, fee_estimator: F, logger: L)
2014 where B::Target: BroadcasterInterface,
2015 F::Target: FeeEstimator,
2018 let block_hash = header.bitcoin_hash();
2019 log_trace!(logger, "Block {} at height {} disconnected", block_hash, height);
2021 if let Some(_) = self.onchain_events_waiting_threshold_conf.remove(&(height + ANTI_REORG_DELAY - 1)) {
2023 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
2024 //- maturing spendable output has transaction paying us has been disconnected
2027 self.onchain_tx_handler.block_disconnected(height, broadcaster, fee_estimator, logger);
2029 self.last_block_hash = block_hash;
2032 pub(super) fn would_broadcast_at_height<L: Deref>(&self, height: u32, logger: &L) -> bool where L::Target: Logger {
2033 // We need to consider all HTLCs which are:
2034 // * in any unrevoked remote commitment transaction, as they could broadcast said
2035 // transactions and we'd end up in a race, or
2036 // * are in our latest local commitment transaction, as this is the thing we will
2037 // broadcast if we go on-chain.
2038 // Note that we consider HTLCs which were below dust threshold here - while they don't
2039 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
2040 // to the source, and if we don't fail the channel we will have to ensure that the next
2041 // updates that peer sends us are update_fails, failing the channel if not. It's probably
2042 // easier to just fail the channel as this case should be rare enough anyway.
2043 macro_rules! scan_commitment {
2044 ($htlcs: expr, $local_tx: expr) => {
2045 for ref htlc in $htlcs {
2046 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
2047 // chain with enough room to claim the HTLC without our counterparty being able to
2048 // time out the HTLC first.
2049 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
2050 // concern is being able to claim the corresponding inbound HTLC (on another
2051 // channel) before it expires. In fact, we don't even really care if our
2052 // counterparty here claims such an outbound HTLC after it expired as long as we
2053 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
2054 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
2055 // we give ourselves a few blocks of headroom after expiration before going
2056 // on-chain for an expired HTLC.
2057 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
2058 // from us until we've reached the point where we go on-chain with the
2059 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
2060 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
2061 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
2062 // inbound_cltv == height + CLTV_CLAIM_BUFFER
2063 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
2064 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
2065 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
2066 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
2067 // The final, above, condition is checked for statically in channelmanager
2068 // with CHECK_CLTV_EXPIRY_SANITY_2.
2069 let htlc_outbound = $local_tx == htlc.offered;
2070 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
2071 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
2072 log_info!(logger, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
2079 scan_commitment!(self.current_local_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
2081 if let Some(ref txid) = self.current_remote_commitment_txid {
2082 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(txid) {
2083 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2086 if let Some(ref txid) = self.prev_remote_commitment_txid {
2087 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(txid) {
2088 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2095 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a local
2096 /// or remote commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
2097 fn is_resolving_htlc_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2098 'outer_loop: for input in &tx.input {
2099 let mut payment_data = None;
2100 let revocation_sig_claim = (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && input.witness[1].len() == 33)
2101 || (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && input.witness[1].len() == 33);
2102 let accepted_preimage_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::AcceptedHTLC);
2103 let offered_preimage_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC);
2105 macro_rules! log_claim {
2106 ($tx_info: expr, $local_tx: expr, $htlc: expr, $source_avail: expr) => {
2107 // We found the output in question, but aren't failing it backwards
2108 // as we have no corresponding source and no valid remote commitment txid
2109 // to try a weak source binding with same-hash, same-value still-valid offered HTLC.
2110 // This implies either it is an inbound HTLC or an outbound HTLC on a revoked transaction.
2111 let outbound_htlc = $local_tx == $htlc.offered;
2112 if ($local_tx && revocation_sig_claim) ||
2113 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
2114 log_error!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
2115 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2116 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2117 if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back" });
2119 log_info!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
2120 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2121 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2122 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
2127 macro_rules! check_htlc_valid_remote {
2128 ($remote_txid: expr, $htlc_output: expr) => {
2129 if let Some(txid) = $remote_txid {
2130 for &(ref pending_htlc, ref pending_source) in self.remote_claimable_outpoints.get(&txid).unwrap() {
2131 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
2132 if let &Some(ref source) = pending_source {
2133 log_claim!("revoked remote commitment tx", false, pending_htlc, true);
2134 payment_data = Some(((**source).clone(), $htlc_output.payment_hash));
2143 macro_rules! scan_commitment {
2144 ($htlcs: expr, $tx_info: expr, $local_tx: expr) => {
2145 for (ref htlc_output, source_option) in $htlcs {
2146 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
2147 if let Some(ref source) = source_option {
2148 log_claim!($tx_info, $local_tx, htlc_output, true);
2149 // We have a resolution of an HTLC either from one of our latest
2150 // local commitment transactions or an unrevoked remote commitment
2151 // transaction. This implies we either learned a preimage, the HTLC
2152 // has timed out, or we screwed up. In any case, we should now
2153 // resolve the source HTLC with the original sender.
2154 payment_data = Some(((*source).clone(), htlc_output.payment_hash));
2155 } else if !$local_tx {
2156 check_htlc_valid_remote!(self.current_remote_commitment_txid, htlc_output);
2157 if payment_data.is_none() {
2158 check_htlc_valid_remote!(self.prev_remote_commitment_txid, htlc_output);
2161 if payment_data.is_none() {
2162 log_claim!($tx_info, $local_tx, htlc_output, false);
2163 continue 'outer_loop;
2170 if input.previous_output.txid == self.current_local_commitment_tx.txid {
2171 scan_commitment!(self.current_local_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2172 "our latest local commitment tx", true);
2174 if let Some(ref prev_local_signed_commitment_tx) = self.prev_local_signed_commitment_tx {
2175 if input.previous_output.txid == prev_local_signed_commitment_tx.txid {
2176 scan_commitment!(prev_local_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2177 "our previous local commitment tx", true);
2180 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(&input.previous_output.txid) {
2181 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
2182 "remote commitment tx", false);
2185 // Check that scan_commitment, above, decided there is some source worth relaying an
2186 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
2187 if let Some((source, payment_hash)) = payment_data {
2188 let mut payment_preimage = PaymentPreimage([0; 32]);
2189 if accepted_preimage_claim {
2190 if !self.pending_htlcs_updated.iter().any(|update| update.source == source) {
2191 payment_preimage.0.copy_from_slice(&input.witness[3]);
2192 self.pending_htlcs_updated.push(HTLCUpdate {
2194 payment_preimage: Some(payment_preimage),
2198 } else if offered_preimage_claim {
2199 if !self.pending_htlcs_updated.iter().any(|update| update.source == source) {
2200 payment_preimage.0.copy_from_slice(&input.witness[1]);
2201 self.pending_htlcs_updated.push(HTLCUpdate {
2203 payment_preimage: Some(payment_preimage),
2208 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);
2209 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2210 hash_map::Entry::Occupied(mut entry) => {
2211 let e = entry.get_mut();
2212 e.retain(|ref event| {
2214 OnchainEvent::HTLCUpdate { ref htlc_update } => {
2215 return htlc_update.0 != source
2220 e.push(OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)});
2222 hash_map::Entry::Vacant(entry) => {
2223 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)}]);
2231 /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
2232 fn is_paying_spendable_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2233 let mut spendable_output = None;
2234 for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
2235 if outp.script_pubkey == self.destination_script {
2236 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2237 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2238 output: outp.clone(),
2241 } else if let Some(ref broadcasted_local_revokable_script) = self.broadcasted_local_revokable_script {
2242 if broadcasted_local_revokable_script.0 == outp.script_pubkey {
2243 spendable_output = Some(SpendableOutputDescriptor::DynamicOutputP2WSH {
2244 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2245 per_commitment_point: broadcasted_local_revokable_script.1,
2246 to_self_delay: self.on_local_tx_csv,
2247 output: outp.clone(),
2248 key_derivation_params: self.keys.key_derivation_params(),
2249 remote_revocation_pubkey: broadcasted_local_revokable_script.2.clone(),
2253 } else if self.remote_payment_script == outp.script_pubkey {
2254 spendable_output = Some(SpendableOutputDescriptor::StaticOutputRemotePayment {
2255 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2256 output: outp.clone(),
2257 key_derivation_params: self.keys.key_derivation_params(),
2260 } else if outp.script_pubkey == self.shutdown_script {
2261 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2262 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2263 output: outp.clone(),
2267 if let Some(spendable_output) = spendable_output {
2268 log_trace!(logger, "Maturing {} until {}", log_spendable!(spendable_output), height + ANTI_REORG_DELAY - 1);
2269 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2270 hash_map::Entry::Occupied(mut entry) => {
2271 let e = entry.get_mut();
2272 e.push(OnchainEvent::MaturingOutput { descriptor: spendable_output });
2274 hash_map::Entry::Vacant(entry) => {
2275 entry.insert(vec![OnchainEvent::MaturingOutput { descriptor: spendable_output }]);
2282 const MAX_ALLOC_SIZE: usize = 64*1024;
2284 impl<ChanSigner: ChannelKeys + Readable> Readable for (BlockHash, ChannelMonitor<ChanSigner>) {
2285 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
2286 macro_rules! unwrap_obj {
2290 Err(_) => return Err(DecodeError::InvalidValue),
2295 let _ver: u8 = Readable::read(reader)?;
2296 let min_ver: u8 = Readable::read(reader)?;
2297 if min_ver > SERIALIZATION_VERSION {
2298 return Err(DecodeError::UnknownVersion);
2301 let latest_update_id: u64 = Readable::read(reader)?;
2302 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
2304 let destination_script = Readable::read(reader)?;
2305 let broadcasted_local_revokable_script = match <u8 as Readable>::read(reader)? {
2307 let revokable_address = Readable::read(reader)?;
2308 let per_commitment_point = Readable::read(reader)?;
2309 let revokable_script = Readable::read(reader)?;
2310 Some((revokable_address, per_commitment_point, revokable_script))
2313 _ => return Err(DecodeError::InvalidValue),
2315 let remote_payment_script = Readable::read(reader)?;
2316 let shutdown_script = Readable::read(reader)?;
2318 let keys = Readable::read(reader)?;
2319 // Technically this can fail and serialize fail a round-trip, but only for serialization of
2320 // barely-init'd ChannelMonitors that we can't do anything with.
2321 let outpoint = OutPoint {
2322 txid: Readable::read(reader)?,
2323 index: Readable::read(reader)?,
2325 let funding_info = (outpoint, Readable::read(reader)?);
2326 let current_remote_commitment_txid = Readable::read(reader)?;
2327 let prev_remote_commitment_txid = Readable::read(reader)?;
2329 let remote_tx_cache = Readable::read(reader)?;
2330 let funding_redeemscript = Readable::read(reader)?;
2331 let channel_value_satoshis = Readable::read(reader)?;
2333 let their_cur_revocation_points = {
2334 let first_idx = <U48 as Readable>::read(reader)?.0;
2338 let first_point = Readable::read(reader)?;
2339 let second_point_slice: [u8; 33] = Readable::read(reader)?;
2340 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
2341 Some((first_idx, first_point, None))
2343 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
2348 let on_local_tx_csv: u16 = Readable::read(reader)?;
2350 let commitment_secrets = Readable::read(reader)?;
2352 macro_rules! read_htlc_in_commitment {
2355 let offered: bool = Readable::read(reader)?;
2356 let amount_msat: u64 = Readable::read(reader)?;
2357 let cltv_expiry: u32 = Readable::read(reader)?;
2358 let payment_hash: PaymentHash = Readable::read(reader)?;
2359 let transaction_output_index: Option<u32> = Readable::read(reader)?;
2361 HTLCOutputInCommitment {
2362 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
2368 let remote_claimable_outpoints_len: u64 = Readable::read(reader)?;
2369 let mut remote_claimable_outpoints = HashMap::with_capacity(cmp::min(remote_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
2370 for _ in 0..remote_claimable_outpoints_len {
2371 let txid: Txid = Readable::read(reader)?;
2372 let htlcs_count: u64 = Readable::read(reader)?;
2373 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
2374 for _ in 0..htlcs_count {
2375 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
2377 if let Some(_) = remote_claimable_outpoints.insert(txid, htlcs) {
2378 return Err(DecodeError::InvalidValue);
2382 let remote_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
2383 let mut remote_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(remote_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
2384 for _ in 0..remote_commitment_txn_on_chain_len {
2385 let txid: Txid = Readable::read(reader)?;
2386 let commitment_number = <U48 as Readable>::read(reader)?.0;
2387 let outputs_count = <u64 as Readable>::read(reader)?;
2388 let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 8));
2389 for _ in 0..outputs_count {
2390 outputs.push(Readable::read(reader)?);
2392 if let Some(_) = remote_commitment_txn_on_chain.insert(txid, (commitment_number, outputs)) {
2393 return Err(DecodeError::InvalidValue);
2397 let remote_hash_commitment_number_len: u64 = Readable::read(reader)?;
2398 let mut remote_hash_commitment_number = HashMap::with_capacity(cmp::min(remote_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
2399 for _ in 0..remote_hash_commitment_number_len {
2400 let payment_hash: PaymentHash = Readable::read(reader)?;
2401 let commitment_number = <U48 as Readable>::read(reader)?.0;
2402 if let Some(_) = remote_hash_commitment_number.insert(payment_hash, commitment_number) {
2403 return Err(DecodeError::InvalidValue);
2407 macro_rules! read_local_tx {
2410 let txid = Readable::read(reader)?;
2411 let revocation_key = Readable::read(reader)?;
2412 let a_htlc_key = Readable::read(reader)?;
2413 let b_htlc_key = Readable::read(reader)?;
2414 let delayed_payment_key = Readable::read(reader)?;
2415 let per_commitment_point = Readable::read(reader)?;
2416 let feerate_per_kw: u32 = Readable::read(reader)?;
2418 let htlcs_len: u64 = Readable::read(reader)?;
2419 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_len as usize, MAX_ALLOC_SIZE / 128));
2420 for _ in 0..htlcs_len {
2421 let htlc = read_htlc_in_commitment!();
2422 let sigs = match <u8 as Readable>::read(reader)? {
2424 1 => Some(Readable::read(reader)?),
2425 _ => return Err(DecodeError::InvalidValue),
2427 htlcs.push((htlc, sigs, Readable::read(reader)?));
2432 revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, per_commitment_point, feerate_per_kw,
2439 let prev_local_signed_commitment_tx = match <u8 as Readable>::read(reader)? {
2442 Some(read_local_tx!())
2444 _ => return Err(DecodeError::InvalidValue),
2446 let current_local_commitment_tx = read_local_tx!();
2448 let current_remote_commitment_number = <U48 as Readable>::read(reader)?.0;
2449 let current_local_commitment_number = <U48 as Readable>::read(reader)?.0;
2451 let payment_preimages_len: u64 = Readable::read(reader)?;
2452 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
2453 for _ in 0..payment_preimages_len {
2454 let preimage: PaymentPreimage = Readable::read(reader)?;
2455 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2456 if let Some(_) = payment_preimages.insert(hash, preimage) {
2457 return Err(DecodeError::InvalidValue);
2461 let pending_htlcs_updated_len: u64 = Readable::read(reader)?;
2462 let mut pending_htlcs_updated = Vec::with_capacity(cmp::min(pending_htlcs_updated_len as usize, MAX_ALLOC_SIZE / (32 + 8*3)));
2463 for _ in 0..pending_htlcs_updated_len {
2464 pending_htlcs_updated.push(Readable::read(reader)?);
2467 let pending_events_len: u64 = Readable::read(reader)?;
2468 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<events::Event>()));
2469 for _ in 0..pending_events_len {
2470 if let Some(event) = MaybeReadable::read(reader)? {
2471 pending_events.push(event);
2475 let last_block_hash: BlockHash = Readable::read(reader)?;
2477 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
2478 let mut onchain_events_waiting_threshold_conf = HashMap::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
2479 for _ in 0..waiting_threshold_conf_len {
2480 let height_target = Readable::read(reader)?;
2481 let events_len: u64 = Readable::read(reader)?;
2482 let mut events = Vec::with_capacity(cmp::min(events_len as usize, MAX_ALLOC_SIZE / 128));
2483 for _ in 0..events_len {
2484 let ev = match <u8 as Readable>::read(reader)? {
2486 let htlc_source = Readable::read(reader)?;
2487 let hash = Readable::read(reader)?;
2488 OnchainEvent::HTLCUpdate {
2489 htlc_update: (htlc_source, hash)
2493 let descriptor = Readable::read(reader)?;
2494 OnchainEvent::MaturingOutput {
2498 _ => return Err(DecodeError::InvalidValue),
2502 onchain_events_waiting_threshold_conf.insert(height_target, events);
2505 let outputs_to_watch_len: u64 = Readable::read(reader)?;
2506 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>>())));
2507 for _ in 0..outputs_to_watch_len {
2508 let txid = Readable::read(reader)?;
2509 let outputs_len: u64 = Readable::read(reader)?;
2510 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Script>()));
2511 for _ in 0..outputs_len {
2512 outputs.push(Readable::read(reader)?);
2514 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
2515 return Err(DecodeError::InvalidValue);
2518 let onchain_tx_handler = Readable::read(reader)?;
2520 let lockdown_from_offchain = Readable::read(reader)?;
2521 let local_tx_signed = Readable::read(reader)?;
2523 Ok((last_block_hash.clone(), ChannelMonitor {
2525 commitment_transaction_number_obscure_factor,
2528 broadcasted_local_revokable_script,
2529 remote_payment_script,
2534 current_remote_commitment_txid,
2535 prev_remote_commitment_txid,
2538 funding_redeemscript,
2539 channel_value_satoshis,
2540 their_cur_revocation_points,
2545 remote_claimable_outpoints,
2546 remote_commitment_txn_on_chain,
2547 remote_hash_commitment_number,
2549 prev_local_signed_commitment_tx,
2550 current_local_commitment_tx,
2551 current_remote_commitment_number,
2552 current_local_commitment_number,
2555 pending_htlcs_updated,
2558 onchain_events_waiting_threshold_conf,
2563 lockdown_from_offchain,
2567 secp_ctx: Secp256k1::new(),
2574 use bitcoin::blockdata::script::{Script, Builder};
2575 use bitcoin::blockdata::opcodes;
2576 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, SigHashType};
2577 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
2578 use bitcoin::util::bip143;
2579 use bitcoin::hashes::Hash;
2580 use bitcoin::hashes::sha256::Hash as Sha256;
2581 use bitcoin::hashes::hex::FromHex;
2582 use bitcoin::hash_types::Txid;
2584 use chain::transaction::OutPoint;
2585 use ln::channelmanager::{PaymentPreimage, PaymentHash};
2586 use ln::channelmonitor::ChannelMonitor;
2587 use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
2589 use ln::chan_utils::{HTLCOutputInCommitment, LocalCommitmentTransaction};
2590 use util::test_utils::TestLogger;
2591 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
2592 use bitcoin::secp256k1::Secp256k1;
2594 use chain::keysinterface::InMemoryChannelKeys;
2597 fn test_prune_preimages() {
2598 let secp_ctx = Secp256k1::new();
2599 let logger = Arc::new(TestLogger::new());
2601 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
2602 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2604 let mut preimages = Vec::new();
2607 let preimage = PaymentPreimage([i; 32]);
2608 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2609 preimages.push((preimage, hash));
2613 macro_rules! preimages_slice_to_htlc_outputs {
2614 ($preimages_slice: expr) => {
2616 let mut res = Vec::new();
2617 for (idx, preimage) in $preimages_slice.iter().enumerate() {
2618 res.push((HTLCOutputInCommitment {
2622 payment_hash: preimage.1.clone(),
2623 transaction_output_index: Some(idx as u32),
2630 macro_rules! preimages_to_local_htlcs {
2631 ($preimages_slice: expr) => {
2633 let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2634 let res: Vec<_> = inp.drain(..).map(|e| { (e.0, None, e.1) }).collect();
2640 macro_rules! test_preimages_exist {
2641 ($preimages_slice: expr, $monitor: expr) => {
2642 for preimage in $preimages_slice {
2643 assert!($monitor.payment_preimages.contains_key(&preimage.1));
2648 let keys = InMemoryChannelKeys::new(
2650 SecretKey::from_slice(&[41; 32]).unwrap(),
2651 SecretKey::from_slice(&[41; 32]).unwrap(),
2652 SecretKey::from_slice(&[41; 32]).unwrap(),
2653 SecretKey::from_slice(&[41; 32]).unwrap(),
2654 SecretKey::from_slice(&[41; 32]).unwrap(),
2660 // Prune with one old state and a local commitment tx holding a few overlaps with the
2662 let mut monitor = ChannelMonitor::new(keys,
2663 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()), 0, &Script::new(),
2664 (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
2665 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
2666 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
2667 10, Script::new(), 46, 0, LocalCommitmentTransaction::dummy());
2669 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..10])).unwrap();
2670 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
2671 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
2672 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
2673 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
2674 for &(ref preimage, ref hash) in preimages.iter() {
2675 monitor.provide_payment_preimage(hash, preimage);
2678 // Now provide a secret, pruning preimages 10-15
2679 let mut secret = [0; 32];
2680 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2681 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2682 assert_eq!(monitor.payment_preimages.len(), 15);
2683 test_preimages_exist!(&preimages[0..10], monitor);
2684 test_preimages_exist!(&preimages[15..20], monitor);
2686 // Now provide a further secret, pruning preimages 15-17
2687 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2688 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2689 assert_eq!(monitor.payment_preimages.len(), 13);
2690 test_preimages_exist!(&preimages[0..10], monitor);
2691 test_preimages_exist!(&preimages[17..20], monitor);
2693 // Now update local commitment tx info, pruning only element 18 as we still care about the
2694 // previous commitment tx's preimages too
2695 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..5])).unwrap();
2696 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2697 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2698 assert_eq!(monitor.payment_preimages.len(), 12);
2699 test_preimages_exist!(&preimages[0..10], monitor);
2700 test_preimages_exist!(&preimages[18..20], monitor);
2702 // But if we do it again, we'll prune 5-10
2703 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..3])).unwrap();
2704 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2705 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2706 assert_eq!(monitor.payment_preimages.len(), 5);
2707 test_preimages_exist!(&preimages[0..5], monitor);
2711 fn test_claim_txn_weight_computation() {
2712 // We test Claim txn weight, knowing that we want expected weigth and
2713 // not actual case to avoid sigs and time-lock delays hell variances.
2715 let secp_ctx = Secp256k1::new();
2716 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
2717 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
2718 let mut sum_actual_sigs = 0;
2720 macro_rules! sign_input {
2721 ($sighash_parts: expr, $input: expr, $idx: expr, $amount: expr, $input_type: expr, $sum_actual_sigs: expr) => {
2722 let htlc = HTLCOutputInCommitment {
2723 offered: if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::OfferedHTLC { true } else { false },
2725 cltv_expiry: 2 << 16,
2726 payment_hash: PaymentHash([1; 32]),
2727 transaction_output_index: Some($idx),
2729 let redeem_script = if *$input_type == InputDescriptors::RevokedOutput { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &pubkey, &pubkey, &pubkey) };
2730 let sighash = hash_to_message!(&$sighash_parts.sighash_all(&$input, &redeem_script, $amount)[..]);
2731 let sig = secp_ctx.sign(&sighash, &privkey);
2732 $input.witness.push(sig.serialize_der().to_vec());
2733 $input.witness[0].push(SigHashType::All as u8);
2734 sum_actual_sigs += $input.witness[0].len();
2735 if *$input_type == InputDescriptors::RevokedOutput {
2736 $input.witness.push(vec!(1));
2737 } else if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::RevokedReceivedHTLC {
2738 $input.witness.push(pubkey.clone().serialize().to_vec());
2739 } else if *$input_type == InputDescriptors::ReceivedHTLC {
2740 $input.witness.push(vec![0]);
2742 $input.witness.push(PaymentPreimage([1; 32]).0.to_vec());
2744 $input.witness.push(redeem_script.into_bytes());
2745 println!("witness[0] {}", $input.witness[0].len());
2746 println!("witness[1] {}", $input.witness[1].len());
2747 println!("witness[2] {}", $input.witness[2].len());
2751 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
2752 let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
2754 // Justice tx with 1 to_local, 2 revoked offered HTLCs, 1 revoked received HTLCs
2755 let mut claim_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2757 claim_tx.input.push(TxIn {
2758 previous_output: BitcoinOutPoint {
2762 script_sig: Script::new(),
2763 sequence: 0xfffffffd,
2764 witness: Vec::new(),
2767 claim_tx.output.push(TxOut {
2768 script_pubkey: script_pubkey.clone(),
2771 let base_weight = claim_tx.get_weight();
2772 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2773 let inputs_des = vec![InputDescriptors::RevokedOutput, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedReceivedHTLC];
2774 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2775 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2777 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));
2779 // Claim tx with 1 offered HTLCs, 3 received HTLCs
2780 claim_tx.input.clear();
2781 sum_actual_sigs = 0;
2783 claim_tx.input.push(TxIn {
2784 previous_output: BitcoinOutPoint {
2788 script_sig: Script::new(),
2789 sequence: 0xfffffffd,
2790 witness: Vec::new(),
2793 let base_weight = claim_tx.get_weight();
2794 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2795 let inputs_des = vec![InputDescriptors::OfferedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC];
2796 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2797 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2799 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));
2801 // Justice tx with 1 revoked HTLC-Success tx output
2802 claim_tx.input.clear();
2803 sum_actual_sigs = 0;
2804 claim_tx.input.push(TxIn {
2805 previous_output: BitcoinOutPoint {
2809 script_sig: Script::new(),
2810 sequence: 0xfffffffd,
2811 witness: Vec::new(),
2813 let base_weight = claim_tx.get_weight();
2814 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2815 let inputs_des = vec![InputDescriptors::RevokedOutput];
2816 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2817 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2819 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));
2822 // Further testing is done in the ChannelManager integration tests.