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 latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date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};
35 use chain::chaininterface::{ChainListener, ChainWatchInterface, BroadcasterInterface, FeeEstimator};
36 use chain::transaction::OutPoint;
37 use chain::keysinterface::{SpendableOutputDescriptor, ChannelKeys};
38 use util::logger::Logger;
39 use util::ser::{Readable, MaybeReadable, Writer, Writeable, U48};
40 use util::{byte_utils, events};
42 use std::collections::{HashMap, hash_map};
44 use std::{hash,cmp, mem};
47 /// An update generated by the underlying Channel itself which contains some new information the
48 /// ChannelMonitor should be made aware of.
49 #[cfg_attr(test, derive(PartialEq))]
52 pub struct ChannelMonitorUpdate {
53 pub(super) updates: Vec<ChannelMonitorUpdateStep>,
54 /// The sequence number of this update. Updates *must* be replayed in-order according to this
55 /// sequence number (and updates may panic if they are not). The update_id values are strictly
56 /// increasing and increase by one for each new update.
58 /// This sequence number is also used to track up to which points updates which returned
59 /// ChannelMonitorUpdateErr::TemporaryFailure have been applied to all copies of a given
60 /// ChannelMonitor when ChannelManager::channel_monitor_updated is called.
64 impl Writeable for ChannelMonitorUpdate {
65 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
66 self.update_id.write(w)?;
67 (self.updates.len() as u64).write(w)?;
68 for update_step in self.updates.iter() {
69 update_step.write(w)?;
74 impl Readable for ChannelMonitorUpdate {
75 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
76 let update_id: u64 = Readable::read(r)?;
77 let len: u64 = Readable::read(r)?;
78 let mut updates = Vec::with_capacity(cmp::min(len as usize, MAX_ALLOC_SIZE / ::std::mem::size_of::<ChannelMonitorUpdateStep>()));
80 updates.push(Readable::read(r)?);
82 Ok(Self { update_id, updates })
86 /// An error enum representing a failure to persist a channel monitor update.
88 pub enum ChannelMonitorUpdateErr {
89 /// Used to indicate a temporary failure (eg connection to a watchtower or remote backup of
90 /// our state failed, but is expected to succeed at some point in the future).
92 /// Such a failure will "freeze" a channel, preventing us from revoking old states or
93 /// submitting new commitment transactions to the remote party. Once the update(s) which failed
94 /// have been successfully applied, ChannelManager::channel_monitor_updated can be used to
95 /// restore the channel to an operational state.
97 /// Note that a given ChannelManager will *never* re-generate a given ChannelMonitorUpdate. If
98 /// you return a TemporaryFailure you must ensure that it is written to disk safely before
99 /// writing out the latest ChannelManager state.
101 /// Even when a channel has been "frozen" updates to the ChannelMonitor can continue to occur
102 /// (eg if an inbound HTLC which we forwarded was claimed upstream resulting in us attempting
103 /// to claim it on this channel) and those updates must be applied wherever they can be. At
104 /// least one such updated ChannelMonitor must be persisted otherwise PermanentFailure should
105 /// be returned to get things on-chain ASAP using only the in-memory copy. Obviously updates to
106 /// the channel which would invalidate previous ChannelMonitors are not made when a channel has
109 /// Note that even if updates made after TemporaryFailure succeed you must still call
110 /// channel_monitor_updated to ensure you have the latest monitor and re-enable normal channel
113 /// Note that the update being processed here will not be replayed for you when you call
114 /// ChannelManager::channel_monitor_updated, so you must store the update itself along
115 /// with the persisted ChannelMonitor on your own local disk prior to returning a
116 /// TemporaryFailure. You may, of course, employ a journaling approach, storing only the
117 /// ChannelMonitorUpdate on disk without updating the monitor itself, replaying the journal at
120 /// For deployments where a copy of ChannelMonitors and other local state are backed up in a
121 /// remote location (with local copies persisted immediately), it is anticipated that all
122 /// updates will return TemporaryFailure until the remote copies could be updated.
124 /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
125 /// different watchtower and cannot update with all watchtowers that were previously informed
126 /// of this channel). This will force-close the channel in question (which will generate one
127 /// final ChannelMonitorUpdate which must be delivered to at least one ChannelMonitor copy).
129 /// Should also be used to indicate a failure to update the local persisted copy of the channel
134 /// General Err type for ChannelMonitor actions. Generally, this implies that the data provided is
135 /// inconsistent with the ChannelMonitor being called. eg for ChannelMonitor::update_monitor this
136 /// means you tried to update a monitor for a different channel or the ChannelMonitorUpdate was
138 /// Contains a human-readable error message.
140 pub struct MonitorUpdateError(pub &'static str);
142 /// Simple structure send back by ManyChannelMonitor in case of HTLC detected onchain from a
143 /// forward channel and from which info are needed to update HTLC in a backward channel.
144 #[derive(Clone, PartialEq)]
145 pub struct HTLCUpdate {
146 pub(super) payment_hash: PaymentHash,
147 pub(super) payment_preimage: Option<PaymentPreimage>,
148 pub(super) source: HTLCSource
150 impl_writeable!(HTLCUpdate, 0, { payment_hash, payment_preimage, source });
152 /// A simple implementation of a ManyChannelMonitor and ChainListener. Can be used to create a
153 /// watchtower or watch our own channels.
155 /// Note that you must provide your own key by which to refer to channels.
157 /// If you're accepting remote monitors (ie are implementing a watchtower), you must verify that
158 /// users cannot overwrite a given channel by providing a duplicate key. ie you should probably
159 /// index by a PublicKey which is required to sign any updates.
161 /// If you're using this for local monitoring of your own channels, you probably want to use
162 /// `OutPoint` as the key, which will give you a ManyChannelMonitor implementation.
163 pub struct SimpleManyChannelMonitor<Key, ChanSigner: ChannelKeys, T: Deref, F: Deref, L: Deref, C: Deref>
164 where T::Target: BroadcasterInterface,
165 F::Target: FeeEstimator,
167 C::Target: ChainWatchInterface,
169 #[cfg(test)] // Used in ChannelManager tests to manipulate channels directly
170 pub monitors: Mutex<HashMap<Key, ChannelMonitor<ChanSigner>>>,
172 monitors: Mutex<HashMap<Key, ChannelMonitor<ChanSigner>>>,
179 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>
180 ChainListener for SimpleManyChannelMonitor<Key, ChanSigner, T, F, L, C>
181 where T::Target: BroadcasterInterface,
182 F::Target: FeeEstimator,
184 C::Target: ChainWatchInterface,
186 fn block_connected(&self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], _indexes_of_txn_matched: &[usize]) {
187 let block_hash = header.bitcoin_hash();
189 let mut monitors = self.monitors.lock().unwrap();
190 for monitor in monitors.values_mut() {
191 let txn_outputs = monitor.block_connected(txn_matched, height, &block_hash, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
193 for (ref txid, ref outputs) in txn_outputs {
194 for (idx, output) in outputs.iter().enumerate() {
195 self.chain_monitor.install_watch_outpoint((txid.clone(), idx as u32), &output.script_pubkey);
202 fn block_disconnected(&self, header: &BlockHeader, disconnected_height: u32) {
203 let block_hash = header.bitcoin_hash();
204 let mut monitors = self.monitors.lock().unwrap();
205 for monitor in monitors.values_mut() {
206 monitor.block_disconnected(disconnected_height, &block_hash, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
211 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>
212 where T::Target: BroadcasterInterface,
213 F::Target: FeeEstimator,
215 C::Target: ChainWatchInterface,
217 /// Creates a new object which can be used to monitor several channels given the chain
218 /// interface with which to register to receive notifications.
219 pub fn new(chain_monitor: C, broadcaster: T, logger: L, feeest: F) -> SimpleManyChannelMonitor<Key, ChanSigner, T, F, L, C> {
220 let res = SimpleManyChannelMonitor {
221 monitors: Mutex::new(HashMap::new()),
225 fee_estimator: feeest,
231 /// Adds or updates the monitor which monitors the channel referred to by the given key.
232 pub fn add_monitor_by_key(&self, key: Key, monitor: ChannelMonitor<ChanSigner>) -> Result<(), MonitorUpdateError> {
233 let mut monitors = self.monitors.lock().unwrap();
234 let entry = match monitors.entry(key) {
235 hash_map::Entry::Occupied(_) => return Err(MonitorUpdateError("Channel monitor for given key is already present")),
236 hash_map::Entry::Vacant(e) => e,
239 let funding_txo = monitor.get_funding_txo();
240 log_trace!(self.logger, "Got new Channel Monitor for channel {}", log_bytes!(funding_txo.0.to_channel_id()[..]));
241 self.chain_monitor.install_watch_tx(&funding_txo.0.txid, &funding_txo.1);
242 self.chain_monitor.install_watch_outpoint((funding_txo.0.txid, funding_txo.0.index as u32), &funding_txo.1);
243 for (txid, outputs) in monitor.get_outputs_to_watch().iter() {
244 for (idx, script) in outputs.iter().enumerate() {
245 self.chain_monitor.install_watch_outpoint((*txid, idx as u32), script);
249 entry.insert(monitor);
253 /// Updates the monitor which monitors the channel referred to by the given key.
254 pub fn update_monitor_by_key(&self, key: Key, update: ChannelMonitorUpdate) -> Result<(), MonitorUpdateError> {
255 let mut monitors = self.monitors.lock().unwrap();
256 match monitors.get_mut(&key) {
257 Some(orig_monitor) => {
258 log_trace!(self.logger, "Updating Channel Monitor for channel {}", log_funding_info!(orig_monitor));
259 orig_monitor.update_monitor(update, &self.broadcaster, &self.logger)
261 None => Err(MonitorUpdateError("No such monitor registered"))
266 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>
267 where T::Target: BroadcasterInterface,
268 F::Target: FeeEstimator,
270 C::Target: ChainWatchInterface,
272 type Keys = ChanSigner;
274 fn add_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor<ChanSigner>) -> Result<(), ChannelMonitorUpdateErr> {
275 match self.add_monitor_by_key(funding_txo, monitor) {
277 Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
281 fn update_monitor(&self, funding_txo: OutPoint, update: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr> {
282 match self.update_monitor_by_key(funding_txo, update) {
284 Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
288 fn get_and_clear_pending_htlcs_updated(&self) -> Vec<HTLCUpdate> {
289 let mut pending_htlcs_updated = Vec::new();
290 for chan in self.monitors.lock().unwrap().values_mut() {
291 pending_htlcs_updated.append(&mut chan.get_and_clear_pending_htlcs_updated());
293 pending_htlcs_updated
297 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>
298 where T::Target: BroadcasterInterface,
299 F::Target: FeeEstimator,
301 C::Target: ChainWatchInterface,
303 fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
304 let mut pending_events = Vec::new();
305 for chan in self.monitors.lock().unwrap().values_mut() {
306 pending_events.append(&mut chan.get_and_clear_pending_events());
312 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
313 /// instead claiming it in its own individual transaction.
314 pub(crate) const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
315 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
316 /// HTLC-Success transaction.
317 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
318 /// transaction confirmed (and we use it in a few more, equivalent, places).
319 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 6;
320 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
321 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
322 /// copies of ChannelMonitors, including watchtowers). We could enforce the contract by failing
323 /// at CLTV expiration height but giving a grace period to our peer may be profitable for us if he
324 /// can provide an over-late preimage. Nevertheless, grace period has to be accounted in our
325 /// CLTV_EXPIRY_DELTA to be secure. Following this policy we may decrease the rate of channel failures
326 /// due to expiration but increase the cost of funds being locked longuer in case of failure.
327 /// This delay also cover a low-power peer being slow to process blocks and so being behind us on
328 /// accurate block height.
329 /// In case of onchain failure to be pass backward we may see the last block of ANTI_REORG_DELAY
330 /// with at worst this delay, so we are not only using this value as a mercy for them but also
331 /// us as a safeguard to delay with enough time.
332 pub(crate) const LATENCY_GRACE_PERIOD_BLOCKS: u32 = 3;
333 /// Number of blocks we wait on seeing a HTLC output being solved before we fail corresponding inbound
334 /// HTLCs. This prevents us from failing backwards and then getting a reorg resulting in us losing money.
335 /// We use also this delay to be sure we can remove our in-flight claim txn from bump candidates buffer.
336 /// It may cause spurrious generation of bumped claim txn but that's allright given the outpoint is already
337 /// solved by a previous claim tx. What we want to avoid is reorg evicting our claim tx and us not
338 /// keeping bumping another claim tx to solve the outpoint.
339 pub(crate) const ANTI_REORG_DELAY: u32 = 6;
340 /// Number of blocks before confirmation at which we fail back an un-relayed HTLC or at which we
341 /// refuse to accept a new HTLC.
343 /// This is used for a few separate purposes:
344 /// 1) if we've received an MPP HTLC to us and it expires within this many blocks and we are
345 /// waiting on additional parts (or waiting on the preimage for any HTLC from the user), we will
347 /// 2) if we receive an HTLC within this many blocks of its expiry (plus one to avoid a race
348 /// condition with the above), we will fail this HTLC without telling the user we received it,
349 /// 3) if we are waiting on a connection or a channel state update to send an HTLC to a peer, and
350 /// that HTLC expires within this many blocks, we will simply fail the HTLC instead.
352 /// (1) is all about protecting us - we need enough time to update the channel state before we hit
353 /// CLTV_CLAIM_BUFFER, at which point we'd go on chain to claim the HTLC with the preimage.
355 /// (2) is the same, but with an additional buffer to avoid accepting an HTLC which is immediately
356 /// in a race condition between the user connecting a block (which would fail it) and the user
357 /// providing us the preimage (which would claim it).
359 /// (3) is about our counterparty - we don't want to relay an HTLC to a counterparty when they may
360 /// end up force-closing the channel on us to claim it.
361 pub(crate) const HTLC_FAIL_BACK_BUFFER: u32 = CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS;
363 #[derive(Clone, PartialEq)]
364 struct LocalSignedTx {
365 /// txid of the transaction in tx, just used to make comparison faster
367 revocation_key: PublicKey,
368 a_htlc_key: PublicKey,
369 b_htlc_key: PublicKey,
370 delayed_payment_key: PublicKey,
371 per_commitment_point: PublicKey,
373 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
376 /// We use this to track remote commitment transactions and htlcs outputs and
377 /// use it to generate any justice or 2nd-stage preimage/timeout transactions.
379 struct RemoteCommitmentTransaction {
380 remote_delayed_payment_base_key: PublicKey,
381 remote_htlc_base_key: PublicKey,
382 on_remote_tx_csv: u16,
383 per_htlc: HashMap<Txid, Vec<HTLCOutputInCommitment>>
386 impl Writeable for RemoteCommitmentTransaction {
387 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
388 self.remote_delayed_payment_base_key.write(w)?;
389 self.remote_htlc_base_key.write(w)?;
390 w.write_all(&byte_utils::be16_to_array(self.on_remote_tx_csv))?;
391 w.write_all(&byte_utils::be64_to_array(self.per_htlc.len() as u64))?;
392 for (ref txid, ref htlcs) in self.per_htlc.iter() {
393 w.write_all(&txid[..])?;
394 w.write_all(&byte_utils::be64_to_array(htlcs.len() as u64))?;
395 for &ref htlc in htlcs.iter() {
402 impl Readable for RemoteCommitmentTransaction {
403 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
404 let remote_commitment_transaction = {
405 let remote_delayed_payment_base_key = Readable::read(r)?;
406 let remote_htlc_base_key = Readable::read(r)?;
407 let on_remote_tx_csv: u16 = Readable::read(r)?;
408 let per_htlc_len: u64 = Readable::read(r)?;
409 let mut per_htlc = HashMap::with_capacity(cmp::min(per_htlc_len as usize, MAX_ALLOC_SIZE / 64));
410 for _ in 0..per_htlc_len {
411 let txid: Txid = Readable::read(r)?;
412 let htlcs_count: u64 = Readable::read(r)?;
413 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
414 for _ in 0..htlcs_count {
415 let htlc = Readable::read(r)?;
418 if let Some(_) = per_htlc.insert(txid, htlcs) {
419 return Err(DecodeError::InvalidValue);
422 RemoteCommitmentTransaction {
423 remote_delayed_payment_base_key,
424 remote_htlc_base_key,
429 Ok(remote_commitment_transaction)
433 /// When ChannelMonitor discovers an onchain outpoint being a step of a channel and that it needs
434 /// to generate a tx to push channel state forward, we cache outpoint-solving tx material to build
435 /// a new bumped one in case of lenghty confirmation delay
436 #[derive(Clone, PartialEq)]
437 pub(crate) enum InputMaterial {
439 per_commitment_point: PublicKey,
440 remote_delayed_payment_base_key: PublicKey,
441 remote_htlc_base_key: PublicKey,
442 per_commitment_key: SecretKey,
443 input_descriptor: InputDescriptors,
445 htlc: Option<HTLCOutputInCommitment>,
446 on_remote_tx_csv: u16,
449 per_commitment_point: PublicKey,
450 remote_delayed_payment_base_key: PublicKey,
451 remote_htlc_base_key: PublicKey,
452 preimage: Option<PaymentPreimage>,
453 htlc: HTLCOutputInCommitment
456 preimage: Option<PaymentPreimage>,
460 funding_redeemscript: Script,
464 impl Writeable for InputMaterial {
465 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
467 &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} => {
468 writer.write_all(&[0; 1])?;
469 per_commitment_point.write(writer)?;
470 remote_delayed_payment_base_key.write(writer)?;
471 remote_htlc_base_key.write(writer)?;
472 writer.write_all(&per_commitment_key[..])?;
473 input_descriptor.write(writer)?;
474 writer.write_all(&byte_utils::be64_to_array(*amount))?;
476 on_remote_tx_csv.write(writer)?;
478 &InputMaterial::RemoteHTLC { ref per_commitment_point, ref remote_delayed_payment_base_key, ref remote_htlc_base_key, ref preimage, ref htlc} => {
479 writer.write_all(&[1; 1])?;
480 per_commitment_point.write(writer)?;
481 remote_delayed_payment_base_key.write(writer)?;
482 remote_htlc_base_key.write(writer)?;
483 preimage.write(writer)?;
486 &InputMaterial::LocalHTLC { ref preimage, ref amount } => {
487 writer.write_all(&[2; 1])?;
488 preimage.write(writer)?;
489 writer.write_all(&byte_utils::be64_to_array(*amount))?;
491 &InputMaterial::Funding { ref funding_redeemscript } => {
492 writer.write_all(&[3; 1])?;
493 funding_redeemscript.write(writer)?;
500 impl Readable for InputMaterial {
501 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
502 let input_material = match <u8 as Readable>::read(reader)? {
504 let per_commitment_point = Readable::read(reader)?;
505 let remote_delayed_payment_base_key = Readable::read(reader)?;
506 let remote_htlc_base_key = Readable::read(reader)?;
507 let per_commitment_key = Readable::read(reader)?;
508 let input_descriptor = Readable::read(reader)?;
509 let amount = Readable::read(reader)?;
510 let htlc = Readable::read(reader)?;
511 let on_remote_tx_csv = Readable::read(reader)?;
512 InputMaterial::Revoked {
513 per_commitment_point,
514 remote_delayed_payment_base_key,
515 remote_htlc_base_key,
524 let per_commitment_point = Readable::read(reader)?;
525 let remote_delayed_payment_base_key = Readable::read(reader)?;
526 let remote_htlc_base_key = Readable::read(reader)?;
527 let preimage = Readable::read(reader)?;
528 let htlc = Readable::read(reader)?;
529 InputMaterial::RemoteHTLC {
530 per_commitment_point,
531 remote_delayed_payment_base_key,
532 remote_htlc_base_key,
538 let preimage = Readable::read(reader)?;
539 let amount = Readable::read(reader)?;
540 InputMaterial::LocalHTLC {
546 InputMaterial::Funding {
547 funding_redeemscript: Readable::read(reader)?,
550 _ => return Err(DecodeError::InvalidValue),
556 /// ClaimRequest is a descriptor structure to communicate between detection
557 /// and reaction module. They are generated by ChannelMonitor while parsing
558 /// onchain txn leaked from a channel and handed over to OnchainTxHandler which
559 /// is responsible for opportunistic aggregation, selecting and enforcing
560 /// bumping logic, building and signing transactions.
561 pub(crate) struct ClaimRequest {
562 // Block height before which claiming is exclusive to one party,
563 // after reaching it, claiming may be contentious.
564 pub(crate) absolute_timelock: u32,
565 // Timeout tx must have nLocktime set which means aggregating multiple
566 // ones must take the higher nLocktime among them to satisfy all of them.
567 // Sadly it has few pitfalls, a) it takes longuer to get fund back b) CLTV_DELTA
568 // of a sooner-HTLC could be swallowed by the highest nLocktime of the HTLC set.
569 // Do simplify we mark them as non-aggregable.
570 pub(crate) aggregable: bool,
571 // Basic bitcoin outpoint (txid, vout)
572 pub(crate) outpoint: BitcoinOutPoint,
573 // Following outpoint type, set of data needed to generate transaction digest
574 // and satisfy witness program.
575 pub(crate) witness_data: InputMaterial
578 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
579 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
580 #[derive(Clone, PartialEq)]
582 /// HTLC output getting solved by a timeout, at maturation we pass upstream payment source information to solve
583 /// inbound HTLC in backward channel. Note, in case of preimage, we pass info to upstream without delay as we can
584 /// only win from it, so it's never an OnchainEvent
586 htlc_update: (HTLCSource, PaymentHash),
589 descriptor: SpendableOutputDescriptor,
593 const SERIALIZATION_VERSION: u8 = 1;
594 const MIN_SERIALIZATION_VERSION: u8 = 1;
596 #[cfg_attr(test, derive(PartialEq))]
598 pub(super) enum ChannelMonitorUpdateStep {
599 LatestLocalCommitmentTXInfo {
600 commitment_tx: LocalCommitmentTransaction,
601 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
603 LatestRemoteCommitmentTXInfo {
604 unsigned_commitment_tx: Transaction, // TODO: We should actually only need the txid here
605 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
606 commitment_number: u64,
607 their_revocation_point: PublicKey,
610 payment_preimage: PaymentPreimage,
616 /// Used to indicate that the no future updates will occur, and likely that the latest local
617 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
619 /// If set to false, we shouldn't broadcast the latest local commitment transaction as we
620 /// think we've fallen behind!
621 should_broadcast: bool,
625 impl Writeable for ChannelMonitorUpdateStep {
626 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
628 &ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { ref commitment_tx, ref htlc_outputs } => {
630 commitment_tx.write(w)?;
631 (htlc_outputs.len() as u64).write(w)?;
632 for &(ref output, ref signature, ref source) in htlc_outputs.iter() {
638 &ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { ref unsigned_commitment_tx, ref htlc_outputs, ref commitment_number, ref their_revocation_point } => {
640 unsigned_commitment_tx.write(w)?;
641 commitment_number.write(w)?;
642 their_revocation_point.write(w)?;
643 (htlc_outputs.len() as u64).write(w)?;
644 for &(ref output, ref source) in htlc_outputs.iter() {
646 source.as_ref().map(|b| b.as_ref()).write(w)?;
649 &ChannelMonitorUpdateStep::PaymentPreimage { ref payment_preimage } => {
651 payment_preimage.write(w)?;
653 &ChannelMonitorUpdateStep::CommitmentSecret { ref idx, ref secret } => {
658 &ChannelMonitorUpdateStep::ChannelForceClosed { ref should_broadcast } => {
660 should_broadcast.write(w)?;
666 impl Readable for ChannelMonitorUpdateStep {
667 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
668 match Readable::read(r)? {
670 Ok(ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo {
671 commitment_tx: Readable::read(r)?,
673 let len: u64 = Readable::read(r)?;
674 let mut res = Vec::new();
676 res.push((Readable::read(r)?, Readable::read(r)?, Readable::read(r)?));
683 Ok(ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo {
684 unsigned_commitment_tx: Readable::read(r)?,
685 commitment_number: Readable::read(r)?,
686 their_revocation_point: Readable::read(r)?,
688 let len: u64 = Readable::read(r)?;
689 let mut res = Vec::new();
691 res.push((Readable::read(r)?, <Option<HTLCSource> as Readable>::read(r)?.map(|o| Box::new(o))));
698 Ok(ChannelMonitorUpdateStep::PaymentPreimage {
699 payment_preimage: Readable::read(r)?,
703 Ok(ChannelMonitorUpdateStep::CommitmentSecret {
704 idx: Readable::read(r)?,
705 secret: Readable::read(r)?,
709 Ok(ChannelMonitorUpdateStep::ChannelForceClosed {
710 should_broadcast: Readable::read(r)?
713 _ => Err(DecodeError::InvalidValue),
718 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
719 /// on-chain transactions to ensure no loss of funds occurs.
721 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
722 /// information and are actively monitoring the chain.
724 /// Pending Events or updated HTLCs which have not yet been read out by
725 /// get_and_clear_pending_htlcs_updated or get_and_clear_pending_events are serialized to disk and
726 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
727 /// gotten are fully handled before re-serializing the new state.
728 pub struct ChannelMonitor<ChanSigner: ChannelKeys> {
729 latest_update_id: u64,
730 commitment_transaction_number_obscure_factor: u64,
732 destination_script: Script,
733 broadcasted_local_revokable_script: Option<(Script, PublicKey, PublicKey)>,
734 remote_payment_script: Script,
735 shutdown_script: Script,
738 funding_info: (OutPoint, Script),
739 current_remote_commitment_txid: Option<Txid>,
740 prev_remote_commitment_txid: Option<Txid>,
742 remote_tx_cache: RemoteCommitmentTransaction,
743 funding_redeemscript: Script,
744 channel_value_satoshis: u64,
745 // first is the idx of the first of the two revocation points
746 their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
748 on_local_tx_csv: u16,
750 commitment_secrets: CounterpartyCommitmentSecrets,
751 remote_claimable_outpoints: HashMap<Txid, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
752 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
753 /// Nor can we figure out their commitment numbers without the commitment transaction they are
754 /// spending. Thus, in order to claim them via revocation key, we track all the remote
755 /// commitment transactions which we find on-chain, mapping them to the commitment number which
756 /// can be used to derive the revocation key and claim the transactions.
757 remote_commitment_txn_on_chain: HashMap<Txid, (u64, Vec<Script>)>,
758 /// Cache used to make pruning of payment_preimages faster.
759 /// Maps payment_hash values to commitment numbers for remote transactions for non-revoked
760 /// remote transactions (ie should remain pretty small).
761 /// Serialized to disk but should generally not be sent to Watchtowers.
762 remote_hash_commitment_number: HashMap<PaymentHash, u64>,
764 // We store two local commitment transactions to avoid any race conditions where we may update
765 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
766 // various monitors for one channel being out of sync, and us broadcasting a local
767 // transaction for which we have deleted claim information on some watchtowers.
768 prev_local_signed_commitment_tx: Option<LocalSignedTx>,
769 current_local_commitment_tx: LocalSignedTx,
771 // Used just for ChannelManager to make sure it has the latest channel data during
773 current_remote_commitment_number: u64,
774 // Used just for ChannelManager to make sure it has the latest channel data during
776 current_local_commitment_number: u64,
778 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
780 pending_htlcs_updated: Vec<HTLCUpdate>,
781 pending_events: Vec<events::Event>,
783 // Used to track onchain events, i.e transactions parts of channels confirmed on chain, on which
784 // we have to take actions once they reach enough confs. Key is a block height timer, i.e we enforce
785 // actions when we receive a block with given height. Actions depend on OnchainEvent type.
786 onchain_events_waiting_threshold_conf: HashMap<u32, Vec<OnchainEvent>>,
788 // If we get serialized out and re-read, we need to make sure that the chain monitoring
789 // interface knows about the TXOs that we want to be notified of spends of. We could probably
790 // be smart and derive them from the above storage fields, but its much simpler and more
791 // Obviously Correct (tm) if we just keep track of them explicitly.
792 outputs_to_watch: HashMap<Txid, Vec<Script>>,
795 pub onchain_tx_handler: OnchainTxHandler<ChanSigner>,
797 onchain_tx_handler: OnchainTxHandler<ChanSigner>,
799 // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
800 // channel has been force-closed. After this is set, no further local commitment transaction
801 // updates may occur, and we panic!() if one is provided.
802 lockdown_from_offchain: bool,
804 // Set once we've signed a local commitment transaction and handed it over to our
805 // OnchainTxHandler. After this is set, no future updates to our local commitment transactions
806 // may occur, and we fail any such monitor updates.
807 local_tx_signed: bool,
809 // We simply modify last_block_hash in Channel's block_connected so that serialization is
810 // consistent but hopefully the users' copy handles block_connected in a consistent way.
811 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
812 // their last_block_hash from its state and not based on updated copies that didn't run through
813 // the full block_connected).
814 pub(crate) last_block_hash: BlockHash,
815 secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
818 /// Simple trait indicating ability to track a set of ChannelMonitors and multiplex events between
819 /// them. Generally should be implemented by keeping a local SimpleManyChannelMonitor and passing
820 /// events to it, while also taking any add/update_monitor events and passing them to some remote
823 /// In general, you must always have at least one local copy in memory, which must never fail to
824 /// update (as it is responsible for broadcasting the latest state in case the channel is closed),
825 /// and then persist it to various on-disk locations. If, for some reason, the in-memory copy fails
826 /// to update (eg out-of-memory or some other condition), you must immediately shut down without
827 /// taking any further action such as writing the current state to disk. This should likely be
828 /// accomplished via panic!() or abort().
830 /// Note that any updates to a channel's monitor *must* be applied to each instance of the
831 /// channel's monitor everywhere (including remote watchtowers) *before* this function returns. If
832 /// an update occurs and a remote watchtower is left with old state, it may broadcast transactions
833 /// which we have revoked, allowing our counterparty to claim all funds in the channel!
835 /// User needs to notify implementors of ManyChannelMonitor when a new block is connected or
836 /// disconnected using their `block_connected` and `block_disconnected` methods. However, rather
837 /// than calling these methods directly, the user should register implementors as listeners to the
838 /// BlockNotifier and call the BlockNotifier's `block_(dis)connected` methods, which will notify
839 /// all registered listeners in one go.
840 pub trait ManyChannelMonitor: Send + Sync {
841 /// The concrete type which signs for transactions and provides access to our channel public
843 type Keys: ChannelKeys;
845 /// Adds a monitor for the given `funding_txo`.
847 /// Implementer must also ensure that the funding_txo txid *and* outpoint are registered with
848 /// any relevant ChainWatchInterfaces such that the provided monitor receives block_connected
849 /// callbacks with the funding transaction, or any spends of it.
851 /// Further, the implementer must also ensure that each output returned in
852 /// monitor.get_outputs_to_watch() is registered to ensure that the provided monitor learns about
853 /// any spends of any of the outputs.
855 /// Any spends of outputs which should have been registered which aren't passed to
856 /// ChannelMonitors via block_connected may result in FUNDS LOSS.
857 fn add_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor<Self::Keys>) -> Result<(), ChannelMonitorUpdateErr>;
859 /// Updates a monitor for the given `funding_txo`.
861 /// Implementer must also ensure that the funding_txo txid *and* outpoint are registered with
862 /// any relevant ChainWatchInterfaces such that the provided monitor receives block_connected
863 /// callbacks with the funding transaction, or any spends of it.
865 /// Further, the implementer must also ensure that each output returned in
866 /// monitor.get_watch_outputs() is registered to ensure that the provided monitor learns about
867 /// any spends of any of the outputs.
869 /// Any spends of outputs which should have been registered which aren't passed to
870 /// ChannelMonitors via block_connected may result in FUNDS LOSS.
871 fn update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr>;
873 /// Used by ChannelManager to get list of HTLC resolved onchain and which needed to be updated
874 /// with success or failure.
876 /// You should probably just call through to
877 /// ChannelMonitor::get_and_clear_pending_htlcs_updated() for each ChannelMonitor and return
879 fn get_and_clear_pending_htlcs_updated(&self) -> Vec<HTLCUpdate>;
882 #[cfg(any(test, feature = "fuzztarget"))]
883 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
884 /// underlying object
885 impl<ChanSigner: ChannelKeys> PartialEq for ChannelMonitor<ChanSigner> {
886 fn eq(&self, other: &Self) -> bool {
887 if self.latest_update_id != other.latest_update_id ||
888 self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
889 self.destination_script != other.destination_script ||
890 self.broadcasted_local_revokable_script != other.broadcasted_local_revokable_script ||
891 self.remote_payment_script != other.remote_payment_script ||
892 self.keys.pubkeys() != other.keys.pubkeys() ||
893 self.funding_info != other.funding_info ||
894 self.current_remote_commitment_txid != other.current_remote_commitment_txid ||
895 self.prev_remote_commitment_txid != other.prev_remote_commitment_txid ||
896 self.remote_tx_cache != other.remote_tx_cache ||
897 self.funding_redeemscript != other.funding_redeemscript ||
898 self.channel_value_satoshis != other.channel_value_satoshis ||
899 self.their_cur_revocation_points != other.their_cur_revocation_points ||
900 self.on_local_tx_csv != other.on_local_tx_csv ||
901 self.commitment_secrets != other.commitment_secrets ||
902 self.remote_claimable_outpoints != other.remote_claimable_outpoints ||
903 self.remote_commitment_txn_on_chain != other.remote_commitment_txn_on_chain ||
904 self.remote_hash_commitment_number != other.remote_hash_commitment_number ||
905 self.prev_local_signed_commitment_tx != other.prev_local_signed_commitment_tx ||
906 self.current_remote_commitment_number != other.current_remote_commitment_number ||
907 self.current_local_commitment_number != other.current_local_commitment_number ||
908 self.current_local_commitment_tx != other.current_local_commitment_tx ||
909 self.payment_preimages != other.payment_preimages ||
910 self.pending_htlcs_updated != other.pending_htlcs_updated ||
911 self.pending_events.len() != other.pending_events.len() || // We trust events to round-trip properly
912 self.onchain_events_waiting_threshold_conf != other.onchain_events_waiting_threshold_conf ||
913 self.outputs_to_watch != other.outputs_to_watch ||
914 self.lockdown_from_offchain != other.lockdown_from_offchain ||
915 self.local_tx_signed != other.local_tx_signed
924 impl<ChanSigner: ChannelKeys + Writeable> ChannelMonitor<ChanSigner> {
925 /// Writes this monitor into the given writer, suitable for writing to disk.
927 /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
928 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
929 /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
930 /// returned block hash and the the current chain and then reconnecting blocks to get to the
931 /// best chain) upon deserializing the object!
932 pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
933 //TODO: We still write out all the serialization here manually instead of using the fancy
934 //serialization framework we have, we should migrate things over to it.
935 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
936 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
938 self.latest_update_id.write(writer)?;
940 // Set in initial Channel-object creation, so should always be set by now:
941 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
943 self.destination_script.write(writer)?;
944 if let Some(ref broadcasted_local_revokable_script) = self.broadcasted_local_revokable_script {
945 writer.write_all(&[0; 1])?;
946 broadcasted_local_revokable_script.0.write(writer)?;
947 broadcasted_local_revokable_script.1.write(writer)?;
948 broadcasted_local_revokable_script.2.write(writer)?;
950 writer.write_all(&[1; 1])?;
953 self.remote_payment_script.write(writer)?;
954 self.shutdown_script.write(writer)?;
956 self.keys.write(writer)?;
957 writer.write_all(&self.funding_info.0.txid[..])?;
958 writer.write_all(&byte_utils::be16_to_array(self.funding_info.0.index))?;
959 self.funding_info.1.write(writer)?;
960 self.current_remote_commitment_txid.write(writer)?;
961 self.prev_remote_commitment_txid.write(writer)?;
963 self.remote_tx_cache.write(writer)?;
964 self.funding_redeemscript.write(writer)?;
965 self.channel_value_satoshis.write(writer)?;
967 match self.their_cur_revocation_points {
968 Some((idx, pubkey, second_option)) => {
969 writer.write_all(&byte_utils::be48_to_array(idx))?;
970 writer.write_all(&pubkey.serialize())?;
971 match second_option {
972 Some(second_pubkey) => {
973 writer.write_all(&second_pubkey.serialize())?;
976 writer.write_all(&[0; 33])?;
981 writer.write_all(&byte_utils::be48_to_array(0))?;
985 writer.write_all(&byte_utils::be16_to_array(self.on_local_tx_csv))?;
987 self.commitment_secrets.write(writer)?;
989 macro_rules! serialize_htlc_in_commitment {
990 ($htlc_output: expr) => {
991 writer.write_all(&[$htlc_output.offered as u8; 1])?;
992 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
993 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
994 writer.write_all(&$htlc_output.payment_hash.0[..])?;
995 $htlc_output.transaction_output_index.write(writer)?;
999 writer.write_all(&byte_utils::be64_to_array(self.remote_claimable_outpoints.len() as u64))?;
1000 for (ref txid, ref htlc_infos) in self.remote_claimable_outpoints.iter() {
1001 writer.write_all(&txid[..])?;
1002 writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
1003 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
1004 serialize_htlc_in_commitment!(htlc_output);
1005 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
1009 writer.write_all(&byte_utils::be64_to_array(self.remote_commitment_txn_on_chain.len() as u64))?;
1010 for (ref txid, &(commitment_number, ref txouts)) in self.remote_commitment_txn_on_chain.iter() {
1011 writer.write_all(&txid[..])?;
1012 writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
1013 (txouts.len() as u64).write(writer)?;
1014 for script in txouts.iter() {
1015 script.write(writer)?;
1019 writer.write_all(&byte_utils::be64_to_array(self.remote_hash_commitment_number.len() as u64))?;
1020 for (ref payment_hash, commitment_number) in self.remote_hash_commitment_number.iter() {
1021 writer.write_all(&payment_hash.0[..])?;
1022 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
1025 macro_rules! serialize_local_tx {
1026 ($local_tx: expr) => {
1027 $local_tx.txid.write(writer)?;
1028 writer.write_all(&$local_tx.revocation_key.serialize())?;
1029 writer.write_all(&$local_tx.a_htlc_key.serialize())?;
1030 writer.write_all(&$local_tx.b_htlc_key.serialize())?;
1031 writer.write_all(&$local_tx.delayed_payment_key.serialize())?;
1032 writer.write_all(&$local_tx.per_commitment_point.serialize())?;
1034 writer.write_all(&byte_utils::be32_to_array($local_tx.feerate_per_kw))?;
1035 writer.write_all(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64))?;
1036 for &(ref htlc_output, ref sig, ref htlc_source) in $local_tx.htlc_outputs.iter() {
1037 serialize_htlc_in_commitment!(htlc_output);
1038 if let &Some(ref their_sig) = sig {
1040 writer.write_all(&their_sig.serialize_compact())?;
1044 htlc_source.write(writer)?;
1049 if let Some(ref prev_local_tx) = self.prev_local_signed_commitment_tx {
1050 writer.write_all(&[1; 1])?;
1051 serialize_local_tx!(prev_local_tx);
1053 writer.write_all(&[0; 1])?;
1056 serialize_local_tx!(self.current_local_commitment_tx);
1058 writer.write_all(&byte_utils::be48_to_array(self.current_remote_commitment_number))?;
1059 writer.write_all(&byte_utils::be48_to_array(self.current_local_commitment_number))?;
1061 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
1062 for payment_preimage in self.payment_preimages.values() {
1063 writer.write_all(&payment_preimage.0[..])?;
1066 writer.write_all(&byte_utils::be64_to_array(self.pending_htlcs_updated.len() as u64))?;
1067 for data in self.pending_htlcs_updated.iter() {
1068 data.write(writer)?;
1071 writer.write_all(&byte_utils::be64_to_array(self.pending_events.len() as u64))?;
1072 for event in self.pending_events.iter() {
1073 event.write(writer)?;
1076 self.last_block_hash.write(writer)?;
1078 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_waiting_threshold_conf.len() as u64))?;
1079 for (ref target, ref events) in self.onchain_events_waiting_threshold_conf.iter() {
1080 writer.write_all(&byte_utils::be32_to_array(**target))?;
1081 writer.write_all(&byte_utils::be64_to_array(events.len() as u64))?;
1082 for ev in events.iter() {
1084 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1086 htlc_update.0.write(writer)?;
1087 htlc_update.1.write(writer)?;
1089 OnchainEvent::MaturingOutput { ref descriptor } => {
1091 descriptor.write(writer)?;
1097 (self.outputs_to_watch.len() as u64).write(writer)?;
1098 for (txid, output_scripts) in self.outputs_to_watch.iter() {
1099 txid.write(writer)?;
1100 (output_scripts.len() as u64).write(writer)?;
1101 for script in output_scripts.iter() {
1102 script.write(writer)?;
1105 self.onchain_tx_handler.write(writer)?;
1107 self.lockdown_from_offchain.write(writer)?;
1108 self.local_tx_signed.write(writer)?;
1114 impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
1115 pub(super) fn new(keys: ChanSigner, shutdown_pubkey: &PublicKey,
1116 on_remote_tx_csv: u16, destination_script: &Script, funding_info: (OutPoint, Script),
1117 remote_htlc_base_key: &PublicKey, remote_delayed_payment_base_key: &PublicKey,
1118 on_local_tx_csv: u16, funding_redeemscript: Script, channel_value_satoshis: u64,
1119 commitment_transaction_number_obscure_factor: u64,
1120 initial_local_commitment_tx: LocalCommitmentTransaction) -> ChannelMonitor<ChanSigner> {
1122 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
1123 let our_channel_close_key_hash = WPubkeyHash::hash(&shutdown_pubkey.serialize());
1124 let shutdown_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
1125 let payment_key_hash = WPubkeyHash::hash(&keys.pubkeys().payment_point.serialize());
1126 let remote_payment_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_key_hash[..]).into_script();
1128 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() };
1130 let mut onchain_tx_handler = OnchainTxHandler::new(destination_script.clone(), keys.clone(), on_local_tx_csv);
1132 let local_tx_sequence = initial_local_commitment_tx.unsigned_tx.input[0].sequence as u64;
1133 let local_tx_locktime = initial_local_commitment_tx.unsigned_tx.lock_time as u64;
1134 let local_commitment_tx = LocalSignedTx {
1135 txid: initial_local_commitment_tx.txid(),
1136 revocation_key: initial_local_commitment_tx.local_keys.revocation_key,
1137 a_htlc_key: initial_local_commitment_tx.local_keys.a_htlc_key,
1138 b_htlc_key: initial_local_commitment_tx.local_keys.b_htlc_key,
1139 delayed_payment_key: initial_local_commitment_tx.local_keys.a_delayed_payment_key,
1140 per_commitment_point: initial_local_commitment_tx.local_keys.per_commitment_point,
1141 feerate_per_kw: initial_local_commitment_tx.feerate_per_kw,
1142 htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
1144 // Returning a monitor error before updating tracking points means in case of using
1145 // a concurrent watchtower implementation for same channel, if this one doesn't
1146 // reject update as we do, you MAY have the latest local valid commitment tx onchain
1147 // for which you want to spend outputs. We're NOT robust again this scenario right
1148 // now but we should consider it later.
1149 onchain_tx_handler.provide_latest_local_tx(initial_local_commitment_tx).unwrap();
1152 latest_update_id: 0,
1153 commitment_transaction_number_obscure_factor,
1155 destination_script: destination_script.clone(),
1156 broadcasted_local_revokable_script: None,
1157 remote_payment_script,
1162 current_remote_commitment_txid: None,
1163 prev_remote_commitment_txid: None,
1166 funding_redeemscript,
1167 channel_value_satoshis: channel_value_satoshis,
1168 their_cur_revocation_points: None,
1172 commitment_secrets: CounterpartyCommitmentSecrets::new(),
1173 remote_claimable_outpoints: HashMap::new(),
1174 remote_commitment_txn_on_chain: HashMap::new(),
1175 remote_hash_commitment_number: HashMap::new(),
1177 prev_local_signed_commitment_tx: None,
1178 current_local_commitment_tx: local_commitment_tx,
1179 current_remote_commitment_number: 1 << 48,
1180 current_local_commitment_number: 0xffff_ffff_ffff - ((((local_tx_sequence & 0xffffff) << 3*8) | (local_tx_locktime as u64 & 0xffffff)) ^ commitment_transaction_number_obscure_factor),
1182 payment_preimages: HashMap::new(),
1183 pending_htlcs_updated: Vec::new(),
1184 pending_events: Vec::new(),
1186 onchain_events_waiting_threshold_conf: HashMap::new(),
1187 outputs_to_watch: HashMap::new(),
1191 lockdown_from_offchain: false,
1192 local_tx_signed: false,
1194 last_block_hash: Default::default(),
1195 secp_ctx: Secp256k1::new(),
1199 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
1200 /// needed by local commitment transactions HTCLs nor by remote ones. Unless we haven't already seen remote
1201 /// commitment transaction's secret, they are de facto pruned (we can use revocation key).
1202 pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
1203 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
1204 return Err(MonitorUpdateError("Previous secret did not match new one"));
1207 // Prune HTLCs from the previous remote commitment tx so we don't generate failure/fulfill
1208 // events for now-revoked/fulfilled HTLCs.
1209 if let Some(txid) = self.prev_remote_commitment_txid.take() {
1210 for &mut (_, ref mut source) in self.remote_claimable_outpoints.get_mut(&txid).unwrap() {
1215 if !self.payment_preimages.is_empty() {
1216 let cur_local_signed_commitment_tx = &self.current_local_commitment_tx;
1217 let prev_local_signed_commitment_tx = self.prev_local_signed_commitment_tx.as_ref();
1218 let min_idx = self.get_min_seen_secret();
1219 let remote_hash_commitment_number = &mut self.remote_hash_commitment_number;
1221 self.payment_preimages.retain(|&k, _| {
1222 for &(ref htlc, _, _) in cur_local_signed_commitment_tx.htlc_outputs.iter() {
1223 if k == htlc.payment_hash {
1227 if let Some(prev_local_commitment_tx) = prev_local_signed_commitment_tx {
1228 for &(ref htlc, _, _) in prev_local_commitment_tx.htlc_outputs.iter() {
1229 if k == htlc.payment_hash {
1234 let contains = if let Some(cn) = remote_hash_commitment_number.get(&k) {
1241 remote_hash_commitment_number.remove(&k);
1250 /// Informs this monitor of the latest remote (ie non-broadcastable) commitment transaction.
1251 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
1252 /// possibly future revocation/preimage information) to claim outputs where possible.
1253 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
1254 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 {
1255 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
1256 // so that a remote monitor doesn't learn anything unless there is a malicious close.
1257 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
1259 for &(ref htlc, _) in &htlc_outputs {
1260 self.remote_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
1263 let new_txid = unsigned_commitment_tx.txid();
1264 log_trace!(logger, "Tracking new remote commitment transaction with txid {} at commitment number {} with {} HTLC outputs", new_txid, commitment_number, htlc_outputs.len());
1265 log_trace!(logger, "New potential remote commitment transaction: {}", encode::serialize_hex(unsigned_commitment_tx));
1266 self.prev_remote_commitment_txid = self.current_remote_commitment_txid.take();
1267 self.current_remote_commitment_txid = Some(new_txid);
1268 self.remote_claimable_outpoints.insert(new_txid, htlc_outputs.clone());
1269 self.current_remote_commitment_number = commitment_number;
1270 //TODO: Merge this into the other per-remote-transaction output storage stuff
1271 match self.their_cur_revocation_points {
1272 Some(old_points) => {
1273 if old_points.0 == commitment_number + 1 {
1274 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
1275 } else if old_points.0 == commitment_number + 2 {
1276 if let Some(old_second_point) = old_points.2 {
1277 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
1279 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1282 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1286 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1289 let mut htlcs = Vec::with_capacity(htlc_outputs.len());
1290 for htlc in htlc_outputs {
1291 if htlc.0.transaction_output_index.is_some() {
1295 self.remote_tx_cache.per_htlc.insert(new_txid, htlcs);
1298 /// Informs this monitor of the latest local (ie broadcastable) commitment transaction. The
1299 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
1300 /// is important that any clones of this channel monitor (including remote clones) by kept
1301 /// up-to-date as our local commitment transaction is updated.
1302 /// Panics if set_on_local_tx_csv has never been called.
1303 pub(super) fn provide_latest_local_commitment_tx_info(&mut self, commitment_tx: LocalCommitmentTransaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), MonitorUpdateError> {
1304 if self.local_tx_signed {
1305 return Err(MonitorUpdateError("A local commitment tx has already been signed, no new local commitment txn can be sent to our counterparty"));
1307 let txid = commitment_tx.txid();
1308 let sequence = commitment_tx.unsigned_tx.input[0].sequence as u64;
1309 let locktime = commitment_tx.unsigned_tx.lock_time as u64;
1310 let mut new_local_commitment_tx = LocalSignedTx {
1312 revocation_key: commitment_tx.local_keys.revocation_key,
1313 a_htlc_key: commitment_tx.local_keys.a_htlc_key,
1314 b_htlc_key: commitment_tx.local_keys.b_htlc_key,
1315 delayed_payment_key: commitment_tx.local_keys.a_delayed_payment_key,
1316 per_commitment_point: commitment_tx.local_keys.per_commitment_point,
1317 feerate_per_kw: commitment_tx.feerate_per_kw,
1318 htlc_outputs: htlc_outputs,
1320 // Returning a monitor error before updating tracking points means in case of using
1321 // a concurrent watchtower implementation for same channel, if this one doesn't
1322 // reject update as we do, you MAY have the latest local valid commitment tx onchain
1323 // for which you want to spend outputs. We're NOT robust again this scenario right
1324 // now but we should consider it later.
1325 if let Err(_) = self.onchain_tx_handler.provide_latest_local_tx(commitment_tx) {
1326 return Err(MonitorUpdateError("Local commitment signed has already been signed, no further update of LOCAL commitment transaction is allowed"));
1328 self.current_local_commitment_number = 0xffff_ffff_ffff - ((((sequence & 0xffffff) << 3*8) | (locktime as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
1329 mem::swap(&mut new_local_commitment_tx, &mut self.current_local_commitment_tx);
1330 self.prev_local_signed_commitment_tx = Some(new_local_commitment_tx);
1334 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
1335 /// commitment_tx_infos which contain the payment hash have been revoked.
1336 pub(super) fn provide_payment_preimage(&mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage) {
1337 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
1340 pub(super) fn broadcast_latest_local_commitment_txn<B: Deref, L: Deref>(&mut self, broadcaster: &B, logger: &L)
1341 where B::Target: BroadcasterInterface,
1344 for tx in self.get_latest_local_commitment_txn(logger).iter() {
1345 broadcaster.broadcast_transaction(tx);
1349 /// Used in Channel to cheat wrt the update_ids since it plays games, will be removed soon!
1350 pub(super) fn update_monitor_ooo<L: Deref>(&mut self, mut updates: ChannelMonitorUpdate, logger: &L) -> Result<(), MonitorUpdateError> where L::Target: Logger {
1351 for update in updates.updates.drain(..) {
1353 ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { commitment_tx, htlc_outputs } => {
1354 if self.lockdown_from_offchain { panic!(); }
1355 self.provide_latest_local_commitment_tx_info(commitment_tx, htlc_outputs)?
1357 ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
1358 self.provide_latest_remote_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point, logger),
1359 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
1360 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
1361 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
1362 self.provide_secret(idx, secret)?,
1363 ChannelMonitorUpdateStep::ChannelForceClosed { .. } => {},
1366 self.latest_update_id = updates.update_id;
1370 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
1373 /// panics if the given update is not the next update by update_id.
1374 pub fn update_monitor<B: Deref, L: Deref>(&mut self, mut updates: ChannelMonitorUpdate, broadcaster: &B, logger: &L) -> Result<(), MonitorUpdateError>
1375 where B::Target: BroadcasterInterface,
1378 if self.latest_update_id + 1 != updates.update_id {
1379 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
1381 for update in updates.updates.drain(..) {
1383 ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { commitment_tx, htlc_outputs } => {
1384 if self.lockdown_from_offchain { panic!(); }
1385 self.provide_latest_local_commitment_tx_info(commitment_tx, htlc_outputs)?
1387 ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
1388 self.provide_latest_remote_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point, logger),
1389 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
1390 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
1391 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
1392 self.provide_secret(idx, secret)?,
1393 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
1394 self.lockdown_from_offchain = true;
1395 if should_broadcast {
1396 self.broadcast_latest_local_commitment_txn(broadcaster, logger);
1398 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");
1403 self.latest_update_id = updates.update_id;
1407 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
1409 pub fn get_latest_update_id(&self) -> u64 {
1410 self.latest_update_id
1413 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
1414 pub fn get_funding_txo(&self) -> &(OutPoint, Script) {
1418 /// Gets a list of txids, with their output scripts (in the order they appear in the
1419 /// transaction), which we must learn about spends of via block_connected().
1420 pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<Script>> {
1421 &self.outputs_to_watch
1424 /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
1425 /// Generally useful when deserializing as during normal operation the return values of
1426 /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
1427 /// that the get_funding_txo outpoint and transaction must also be monitored for!).
1428 pub fn get_monitored_outpoints(&self) -> Vec<(Txid, u32, &Script)> {
1429 let mut res = Vec::with_capacity(self.remote_commitment_txn_on_chain.len() * 2);
1430 for (ref txid, &(_, ref outputs)) in self.remote_commitment_txn_on_chain.iter() {
1431 for (idx, output) in outputs.iter().enumerate() {
1432 res.push(((*txid).clone(), idx as u32, output));
1438 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1439 /// ChannelManager via ManyChannelMonitor::get_and_clear_pending_htlcs_updated().
1440 pub fn get_and_clear_pending_htlcs_updated(&mut self) -> Vec<HTLCUpdate> {
1441 let mut ret = Vec::new();
1442 mem::swap(&mut ret, &mut self.pending_htlcs_updated);
1446 /// Gets the list of pending events which were generated by previous actions, clearing the list
1449 /// This is called by ManyChannelMonitor::get_and_clear_pending_events() and is equivalent to
1450 /// EventsProvider::get_and_clear_pending_events() except that it requires &mut self as we do
1451 /// no internal locking in ChannelMonitors.
1452 pub fn get_and_clear_pending_events(&mut self) -> Vec<events::Event> {
1453 let mut ret = Vec::new();
1454 mem::swap(&mut ret, &mut self.pending_events);
1458 /// Can only fail if idx is < get_min_seen_secret
1459 pub(super) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
1460 self.commitment_secrets.get_secret(idx)
1463 pub(super) fn get_min_seen_secret(&self) -> u64 {
1464 self.commitment_secrets.get_min_seen_secret()
1467 pub(super) fn get_cur_remote_commitment_number(&self) -> u64 {
1468 self.current_remote_commitment_number
1471 pub(super) fn get_cur_local_commitment_number(&self) -> u64 {
1472 self.current_local_commitment_number
1475 /// Attempts to claim a remote commitment transaction's outputs using the revocation key and
1476 /// data in remote_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
1477 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
1478 /// HTLC-Success/HTLC-Timeout transactions.
1479 /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
1480 /// revoked remote commitment tx
1481 fn check_spend_remote_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) where L::Target: Logger {
1482 // Most secp and related errors trying to create keys means we have no hope of constructing
1483 // a spend transaction...so we return no transactions to broadcast
1484 let mut claimable_outpoints = Vec::new();
1485 let mut watch_outputs = Vec::new();
1487 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1488 let per_commitment_option = self.remote_claimable_outpoints.get(&commitment_txid);
1490 macro_rules! ignore_error {
1491 ( $thing : expr ) => {
1494 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs))
1499 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);
1500 if commitment_number >= self.get_min_seen_secret() {
1501 let secret = self.get_secret(commitment_number).unwrap();
1502 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1503 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1504 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.keys.pubkeys().revocation_basepoint));
1505 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));
1507 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.remote_tx_cache.on_remote_tx_csv, &delayed_key);
1508 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1510 // First, process non-htlc outputs (to_local & to_remote)
1511 for (idx, outp) in tx.output.iter().enumerate() {
1512 if outp.script_pubkey == revokeable_p2wsh {
1513 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};
1514 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});
1518 // Then, try to find revoked htlc outputs
1519 if let Some(ref per_commitment_data) = per_commitment_option {
1520 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1521 if let Some(transaction_output_index) = htlc.transaction_output_index {
1522 if transaction_output_index as usize >= tx.output.len() ||
1523 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1524 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1526 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};
1527 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable: true, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1532 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
1533 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
1534 // We're definitely a remote commitment transaction!
1535 log_trace!(logger, "Got broadcast of revoked remote commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
1536 watch_outputs.append(&mut tx.output.clone());
1537 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1539 macro_rules! check_htlc_fails {
1540 ($txid: expr, $commitment_tx: expr) => {
1541 if let Some(ref outpoints) = self.remote_claimable_outpoints.get($txid) {
1542 for &(ref htlc, ref source_option) in outpoints.iter() {
1543 if let &Some(ref source) = source_option {
1544 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), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1545 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1546 hash_map::Entry::Occupied(mut entry) => {
1547 let e = entry.get_mut();
1548 e.retain(|ref event| {
1550 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1551 return htlc_update.0 != **source
1556 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1558 hash_map::Entry::Vacant(entry) => {
1559 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1567 if let Some(ref txid) = self.current_remote_commitment_txid {
1568 check_htlc_fails!(txid, "current");
1570 if let Some(ref txid) = self.prev_remote_commitment_txid {
1571 check_htlc_fails!(txid, "remote");
1573 // No need to check local commitment txn, symmetric HTLCSource must be present as per-htlc data on remote commitment tx
1575 } else if let Some(per_commitment_data) = per_commitment_option {
1576 // While this isn't useful yet, there is a potential race where if a counterparty
1577 // revokes a state at the same time as the commitment transaction for that state is
1578 // confirmed, and the watchtower receives the block before the user, the user could
1579 // upload a new ChannelMonitor with the revocation secret but the watchtower has
1580 // already processed the block, resulting in the remote_commitment_txn_on_chain entry
1581 // not being generated by the above conditional. Thus, to be safe, we go ahead and
1583 watch_outputs.append(&mut tx.output.clone());
1584 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1586 log_trace!(logger, "Got broadcast of non-revoked remote commitment transaction {}", commitment_txid);
1588 macro_rules! check_htlc_fails {
1589 ($txid: expr, $commitment_tx: expr, $id: tt) => {
1590 if let Some(ref latest_outpoints) = self.remote_claimable_outpoints.get($txid) {
1591 $id: for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1592 if let &Some(ref source) = source_option {
1593 // Check if the HTLC is present in the commitment transaction that was
1594 // broadcast, but not if it was below the dust limit, which we should
1595 // fail backwards immediately as there is no way for us to learn the
1596 // payment_preimage.
1597 // Note that if the dust limit were allowed to change between
1598 // commitment transactions we'd want to be check whether *any*
1599 // broadcastable commitment transaction has the HTLC in it, but it
1600 // cannot currently change after channel initialization, so we don't
1602 for &(ref broadcast_htlc, ref broadcast_source) in per_commitment_data.iter() {
1603 if broadcast_htlc.transaction_output_index.is_some() && Some(source) == broadcast_source.as_ref() {
1607 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);
1608 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1609 hash_map::Entry::Occupied(mut entry) => {
1610 let e = entry.get_mut();
1611 e.retain(|ref event| {
1613 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1614 return htlc_update.0 != **source
1619 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1621 hash_map::Entry::Vacant(entry) => {
1622 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1630 if let Some(ref txid) = self.current_remote_commitment_txid {
1631 check_htlc_fails!(txid, "current", 'current_loop);
1633 if let Some(ref txid) = self.prev_remote_commitment_txid {
1634 check_htlc_fails!(txid, "previous", 'prev_loop);
1637 if let Some(revocation_points) = self.their_cur_revocation_points {
1638 let revocation_point_option =
1639 if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1640 else if let Some(point) = revocation_points.2.as_ref() {
1641 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1643 if let Some(revocation_point) = revocation_point_option {
1644 self.remote_payment_script = {
1645 // Note that the Network here is ignored as we immediately drop the address for the
1646 // script_pubkey version
1647 let payment_hash160 = WPubkeyHash::hash(&self.keys.pubkeys().payment_point.serialize());
1648 Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_hash160[..]).into_script()
1651 // Then, try to find htlc outputs
1652 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1653 if let Some(transaction_output_index) = htlc.transaction_output_index {
1654 if transaction_output_index as usize >= tx.output.len() ||
1655 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1656 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1658 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
1659 let aggregable = if !htlc.offered { false } else { true };
1660 if preimage.is_some() || !htlc.offered {
1661 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() };
1662 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1669 (claimable_outpoints, (commitment_txid, watch_outputs))
1672 /// Attempts to claim a remote HTLC-Success/HTLC-Timeout's outputs using the revocation key
1673 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 {
1674 let htlc_txid = tx.txid();
1675 if tx.input.len() != 1 || tx.output.len() != 1 || tx.input[0].witness.len() != 5 {
1676 return (Vec::new(), None)
1679 macro_rules! ignore_error {
1680 ( $thing : expr ) => {
1683 Err(_) => return (Vec::new(), None)
1688 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
1689 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1690 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1692 log_trace!(logger, "Remote HTLC broadcast {}:{}", htlc_txid, 0);
1693 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 };
1694 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 });
1695 (claimable_outpoints, Some((htlc_txid, tx.output.clone())))
1698 fn broadcast_by_local_state(&self, commitment_tx: &Transaction, local_tx: &LocalSignedTx) -> (Vec<ClaimRequest>, Vec<TxOut>, Option<(Script, PublicKey, PublicKey)>) {
1699 let mut claim_requests = Vec::with_capacity(local_tx.htlc_outputs.len());
1700 let mut watch_outputs = Vec::with_capacity(local_tx.htlc_outputs.len());
1702 let redeemscript = chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.on_local_tx_csv, &local_tx.delayed_payment_key);
1703 let broadcasted_local_revokable_script = Some((redeemscript.to_v0_p2wsh(), local_tx.per_commitment_point.clone(), local_tx.revocation_key.clone()));
1705 for &(ref htlc, _, _) in local_tx.htlc_outputs.iter() {
1706 if let Some(transaction_output_index) = htlc.transaction_output_index {
1707 claim_requests.push(ClaimRequest { absolute_timelock: ::std::u32::MAX, aggregable: false, outpoint: BitcoinOutPoint { txid: local_tx.txid, vout: transaction_output_index as u32 },
1708 witness_data: InputMaterial::LocalHTLC {
1709 preimage: if !htlc.offered {
1710 if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1711 Some(preimage.clone())
1713 // We can't build an HTLC-Success transaction without the preimage
1717 amount: htlc.amount_msat,
1719 watch_outputs.push(commitment_tx.output[transaction_output_index as usize].clone());
1723 (claim_requests, watch_outputs, broadcasted_local_revokable_script)
1726 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1727 /// revoked using data in local_claimable_outpoints.
1728 /// Should not be used if check_spend_revoked_transaction succeeds.
1729 fn check_spend_local_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) where L::Target: Logger {
1730 let commitment_txid = tx.txid();
1731 let mut claim_requests = Vec::new();
1732 let mut watch_outputs = Vec::new();
1734 macro_rules! wait_threshold_conf {
1735 ($height: expr, $source: expr, $commitment_tx: expr, $payment_hash: expr) => {
1736 log_trace!(logger, "Failing HTLC with payment_hash {} from {} local commitment tx due to broadcast of transaction, waiting confirmation (at height{})", log_bytes!($payment_hash.0), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1737 match self.onchain_events_waiting_threshold_conf.entry($height + ANTI_REORG_DELAY - 1) {
1738 hash_map::Entry::Occupied(mut entry) => {
1739 let e = entry.get_mut();
1740 e.retain(|ref event| {
1742 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1743 return htlc_update.0 != $source
1748 e.push(OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)});
1750 hash_map::Entry::Vacant(entry) => {
1751 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)}]);
1757 macro_rules! append_onchain_update {
1758 ($updates: expr) => {
1759 claim_requests = $updates.0;
1760 watch_outputs.append(&mut $updates.1);
1761 self.broadcasted_local_revokable_script = $updates.2;
1765 // HTLCs set may differ between last and previous local commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
1766 let mut is_local_tx = false;
1768 if self.current_local_commitment_tx.txid == commitment_txid {
1770 log_trace!(logger, "Got latest local commitment tx broadcast, searching for available HTLCs to claim");
1771 let mut res = self.broadcast_by_local_state(tx, &self.current_local_commitment_tx);
1772 append_onchain_update!(res);
1773 } else if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1774 if local_tx.txid == commitment_txid {
1776 log_trace!(logger, "Got previous local commitment tx broadcast, searching for available HTLCs to claim");
1777 let mut res = self.broadcast_by_local_state(tx, local_tx);
1778 append_onchain_update!(res);
1782 macro_rules! fail_dust_htlcs_after_threshold_conf {
1783 ($local_tx: expr) => {
1784 for &(ref htlc, _, ref source) in &$local_tx.htlc_outputs {
1785 if htlc.transaction_output_index.is_none() {
1786 if let &Some(ref source) = source {
1787 wait_threshold_conf!(height, source.clone(), "lastest", htlc.payment_hash.clone());
1795 fail_dust_htlcs_after_threshold_conf!(self.current_local_commitment_tx);
1796 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1797 fail_dust_htlcs_after_threshold_conf!(local_tx);
1801 (claim_requests, (commitment_txid, watch_outputs))
1804 /// Used by ChannelManager deserialization to broadcast the latest local state if its copy of
1805 /// the Channel was out-of-date. You may use it to get a broadcastable local toxic tx in case of
1806 /// fallen-behind, i.e when receiving a channel_reestablish with a proof that our remote side knows
1807 /// a higher revocation secret than the local commitment number we are aware of. Broadcasting these
1808 /// transactions are UNSAFE, as they allow remote side to punish you. Nevertheless you may want to
1809 /// broadcast them if remote don't close channel with his higher commitment transaction after a
1810 /// substantial amount of time (a month or even a year) to get back funds. Best may be to contact
1811 /// out-of-band the other node operator to coordinate with him if option is available to you.
1812 /// In any-case, choice is up to the user.
1813 pub fn get_latest_local_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1814 log_trace!(logger, "Getting signed latest local commitment transaction!");
1815 self.local_tx_signed = true;
1816 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_local_tx(&self.funding_redeemscript) {
1817 let txid = commitment_tx.txid();
1818 let mut res = vec![commitment_tx];
1819 for htlc in self.current_local_commitment_tx.htlc_outputs.iter() {
1820 if let Some(vout) = htlc.0.transaction_output_index {
1821 let preimage = if !htlc.0.offered {
1822 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1823 // We can't build an HTLC-Success transaction without the preimage
1827 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
1828 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1833 // 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.
1834 // The data will be re-generated and tracked in check_spend_local_transaction if we get a confirmation.
1840 /// Unsafe test-only version of get_latest_local_commitment_txn used by our test framework
1841 /// to bypass LocalCommitmentTransaction state update lockdown after signature and generate
1842 /// revoked commitment transaction.
1844 pub fn unsafe_get_latest_local_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1845 log_trace!(logger, "Getting signed copy of latest local commitment transaction!");
1846 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_copy_local_tx(&self.funding_redeemscript) {
1847 let txid = commitment_tx.txid();
1848 let mut res = vec![commitment_tx];
1849 for htlc in self.current_local_commitment_tx.htlc_outputs.iter() {
1850 if let Some(vout) = htlc.0.transaction_output_index {
1851 let preimage = if !htlc.0.offered {
1852 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1853 // We can't build an HTLC-Success transaction without the preimage
1857 if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
1858 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1868 /// Called by SimpleManyChannelMonitor::block_connected, which implements
1869 /// ChainListener::block_connected.
1870 /// Eventually this should be pub and, roughly, implement ChainListener, however this requires
1871 /// &mut self, as well as returns new spendable outputs and outpoints to watch for spending of
1873 fn block_connected<B: Deref, F: Deref, L: Deref>(&mut self, txn_matched: &[&Transaction], height: u32, block_hash: &BlockHash, broadcaster: B, fee_estimator: F, logger: L)-> Vec<(Txid, Vec<TxOut>)>
1874 where B::Target: BroadcasterInterface,
1875 F::Target: FeeEstimator,
1878 for tx in txn_matched {
1879 let mut output_val = 0;
1880 for out in tx.output.iter() {
1881 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1882 output_val += out.value;
1883 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1887 log_trace!(logger, "Block {} at height {} connected with {} txn matched", block_hash, height, txn_matched.len());
1888 let mut watch_outputs = Vec::new();
1889 let mut claimable_outpoints = Vec::new();
1890 for tx in txn_matched {
1891 if tx.input.len() == 1 {
1892 // Assuming our keys were not leaked (in which case we're screwed no matter what),
1893 // commitment transactions and HTLC transactions will all only ever have one input,
1894 // which is an easy way to filter out any potential non-matching txn for lazy
1896 let prevout = &tx.input[0].previous_output;
1897 if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
1898 if (tx.input[0].sequence >> 8*3) as u8 == 0x80 && (tx.lock_time >> 8*3) as u8 == 0x20 {
1899 let (mut new_outpoints, new_outputs) = self.check_spend_remote_transaction(&tx, height, &logger);
1900 if !new_outputs.1.is_empty() {
1901 watch_outputs.push(new_outputs);
1903 if new_outpoints.is_empty() {
1904 let (mut new_outpoints, new_outputs) = self.check_spend_local_transaction(&tx, height, &logger);
1905 if !new_outputs.1.is_empty() {
1906 watch_outputs.push(new_outputs);
1908 claimable_outpoints.append(&mut new_outpoints);
1910 claimable_outpoints.append(&mut new_outpoints);
1913 if let Some(&(commitment_number, _)) = self.remote_commitment_txn_on_chain.get(&prevout.txid) {
1914 let (mut new_outpoints, new_outputs_option) = self.check_spend_remote_htlc(&tx, commitment_number, height, &logger);
1915 claimable_outpoints.append(&mut new_outpoints);
1916 if let Some(new_outputs) = new_outputs_option {
1917 watch_outputs.push(new_outputs);
1922 // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
1923 // can also be resolved in a few other ways which can have more than one output. Thus,
1924 // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
1925 self.is_resolving_htlc_output(&tx, height, &logger);
1927 self.is_paying_spendable_output(&tx, height, &logger);
1929 let should_broadcast = self.would_broadcast_at_height(height, &logger);
1930 if should_broadcast {
1931 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() }});
1933 if should_broadcast {
1934 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_local_tx(&self.funding_redeemscript) {
1935 let (mut new_outpoints, new_outputs, _) = self.broadcast_by_local_state(&commitment_tx, &self.current_local_commitment_tx);
1936 if !new_outputs.is_empty() {
1937 watch_outputs.push((self.current_local_commitment_tx.txid.clone(), new_outputs));
1939 claimable_outpoints.append(&mut new_outpoints);
1942 if let Some(events) = self.onchain_events_waiting_threshold_conf.remove(&height) {
1945 OnchainEvent::HTLCUpdate { htlc_update } => {
1946 log_trace!(logger, "HTLC {} failure update has got enough confirmations to be passed upstream", log_bytes!((htlc_update.1).0));
1947 self.pending_htlcs_updated.push(HTLCUpdate {
1948 payment_hash: htlc_update.1,
1949 payment_preimage: None,
1950 source: htlc_update.0,
1953 OnchainEvent::MaturingOutput { descriptor } => {
1954 log_trace!(logger, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
1955 self.pending_events.push(events::Event::SpendableOutputs {
1956 outputs: vec![descriptor]
1962 self.onchain_tx_handler.block_connected(txn_matched, claimable_outpoints, height, &*broadcaster, &*fee_estimator, &*logger);
1964 self.last_block_hash = block_hash.clone();
1965 for &(ref txid, ref output_scripts) in watch_outputs.iter() {
1966 self.outputs_to_watch.insert(txid.clone(), output_scripts.iter().map(|o| o.script_pubkey.clone()).collect());
1972 fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, height: u32, block_hash: &BlockHash, broadcaster: B, fee_estimator: F, logger: L)
1973 where B::Target: BroadcasterInterface,
1974 F::Target: FeeEstimator,
1977 log_trace!(logger, "Block {} at height {} disconnected", block_hash, height);
1978 if let Some(_) = self.onchain_events_waiting_threshold_conf.remove(&(height + ANTI_REORG_DELAY - 1)) {
1980 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
1981 //- maturing spendable output has transaction paying us has been disconnected
1984 self.onchain_tx_handler.block_disconnected(height, broadcaster, fee_estimator, logger);
1986 self.last_block_hash = block_hash.clone();
1989 pub(super) fn would_broadcast_at_height<L: Deref>(&self, height: u32, logger: &L) -> bool where L::Target: Logger {
1990 // We need to consider all HTLCs which are:
1991 // * in any unrevoked remote commitment transaction, as they could broadcast said
1992 // transactions and we'd end up in a race, or
1993 // * are in our latest local commitment transaction, as this is the thing we will
1994 // broadcast if we go on-chain.
1995 // Note that we consider HTLCs which were below dust threshold here - while they don't
1996 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
1997 // to the source, and if we don't fail the channel we will have to ensure that the next
1998 // updates that peer sends us are update_fails, failing the channel if not. It's probably
1999 // easier to just fail the channel as this case should be rare enough anyway.
2000 macro_rules! scan_commitment {
2001 ($htlcs: expr, $local_tx: expr) => {
2002 for ref htlc in $htlcs {
2003 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
2004 // chain with enough room to claim the HTLC without our counterparty being able to
2005 // time out the HTLC first.
2006 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
2007 // concern is being able to claim the corresponding inbound HTLC (on another
2008 // channel) before it expires. In fact, we don't even really care if our
2009 // counterparty here claims such an outbound HTLC after it expired as long as we
2010 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
2011 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
2012 // we give ourselves a few blocks of headroom after expiration before going
2013 // on-chain for an expired HTLC.
2014 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
2015 // from us until we've reached the point where we go on-chain with the
2016 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
2017 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
2018 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
2019 // inbound_cltv == height + CLTV_CLAIM_BUFFER
2020 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
2021 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
2022 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
2023 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
2024 // The final, above, condition is checked for statically in channelmanager
2025 // with CHECK_CLTV_EXPIRY_SANITY_2.
2026 let htlc_outbound = $local_tx == htlc.offered;
2027 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
2028 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
2029 log_info!(logger, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
2036 scan_commitment!(self.current_local_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
2038 if let Some(ref txid) = self.current_remote_commitment_txid {
2039 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(txid) {
2040 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2043 if let Some(ref txid) = self.prev_remote_commitment_txid {
2044 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(txid) {
2045 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2052 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a local
2053 /// or remote commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
2054 fn is_resolving_htlc_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2055 'outer_loop: for input in &tx.input {
2056 let mut payment_data = None;
2057 let revocation_sig_claim = (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && input.witness[1].len() == 33)
2058 || (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && input.witness[1].len() == 33);
2059 let accepted_preimage_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::AcceptedHTLC);
2060 let offered_preimage_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC);
2062 macro_rules! log_claim {
2063 ($tx_info: expr, $local_tx: expr, $htlc: expr, $source_avail: expr) => {
2064 // We found the output in question, but aren't failing it backwards
2065 // as we have no corresponding source and no valid remote commitment txid
2066 // to try a weak source binding with same-hash, same-value still-valid offered HTLC.
2067 // This implies either it is an inbound HTLC or an outbound HTLC on a revoked transaction.
2068 let outbound_htlc = $local_tx == $htlc.offered;
2069 if ($local_tx && revocation_sig_claim) ||
2070 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
2071 log_error!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
2072 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2073 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2074 if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back" });
2076 log_info!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
2077 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2078 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2079 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
2084 macro_rules! check_htlc_valid_remote {
2085 ($remote_txid: expr, $htlc_output: expr) => {
2086 if let Some(txid) = $remote_txid {
2087 for &(ref pending_htlc, ref pending_source) in self.remote_claimable_outpoints.get(&txid).unwrap() {
2088 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
2089 if let &Some(ref source) = pending_source {
2090 log_claim!("revoked remote commitment tx", false, pending_htlc, true);
2091 payment_data = Some(((**source).clone(), $htlc_output.payment_hash));
2100 macro_rules! scan_commitment {
2101 ($htlcs: expr, $tx_info: expr, $local_tx: expr) => {
2102 for (ref htlc_output, source_option) in $htlcs {
2103 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
2104 if let Some(ref source) = source_option {
2105 log_claim!($tx_info, $local_tx, htlc_output, true);
2106 // We have a resolution of an HTLC either from one of our latest
2107 // local commitment transactions or an unrevoked remote commitment
2108 // transaction. This implies we either learned a preimage, the HTLC
2109 // has timed out, or we screwed up. In any case, we should now
2110 // resolve the source HTLC with the original sender.
2111 payment_data = Some(((*source).clone(), htlc_output.payment_hash));
2112 } else if !$local_tx {
2113 check_htlc_valid_remote!(self.current_remote_commitment_txid, htlc_output);
2114 if payment_data.is_none() {
2115 check_htlc_valid_remote!(self.prev_remote_commitment_txid, htlc_output);
2118 if payment_data.is_none() {
2119 log_claim!($tx_info, $local_tx, htlc_output, false);
2120 continue 'outer_loop;
2127 if input.previous_output.txid == self.current_local_commitment_tx.txid {
2128 scan_commitment!(self.current_local_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2129 "our latest local commitment tx", true);
2131 if let Some(ref prev_local_signed_commitment_tx) = self.prev_local_signed_commitment_tx {
2132 if input.previous_output.txid == prev_local_signed_commitment_tx.txid {
2133 scan_commitment!(prev_local_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2134 "our previous local commitment tx", true);
2137 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(&input.previous_output.txid) {
2138 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
2139 "remote commitment tx", false);
2142 // Check that scan_commitment, above, decided there is some source worth relaying an
2143 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
2144 if let Some((source, payment_hash)) = payment_data {
2145 let mut payment_preimage = PaymentPreimage([0; 32]);
2146 if accepted_preimage_claim {
2147 if !self.pending_htlcs_updated.iter().any(|update| update.source == source) {
2148 payment_preimage.0.copy_from_slice(&input.witness[3]);
2149 self.pending_htlcs_updated.push(HTLCUpdate {
2151 payment_preimage: Some(payment_preimage),
2155 } else if offered_preimage_claim {
2156 if !self.pending_htlcs_updated.iter().any(|update| update.source == source) {
2157 payment_preimage.0.copy_from_slice(&input.witness[1]);
2158 self.pending_htlcs_updated.push(HTLCUpdate {
2160 payment_preimage: Some(payment_preimage),
2165 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);
2166 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2167 hash_map::Entry::Occupied(mut entry) => {
2168 let e = entry.get_mut();
2169 e.retain(|ref event| {
2171 OnchainEvent::HTLCUpdate { ref htlc_update } => {
2172 return htlc_update.0 != source
2177 e.push(OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)});
2179 hash_map::Entry::Vacant(entry) => {
2180 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)}]);
2188 /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
2189 fn is_paying_spendable_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2190 let mut spendable_output = None;
2191 for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
2192 if outp.script_pubkey == self.destination_script {
2193 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2194 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2195 output: outp.clone(),
2198 } else if let Some(ref broadcasted_local_revokable_script) = self.broadcasted_local_revokable_script {
2199 if broadcasted_local_revokable_script.0 == outp.script_pubkey {
2200 spendable_output = Some(SpendableOutputDescriptor::DynamicOutputP2WSH {
2201 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2202 per_commitment_point: broadcasted_local_revokable_script.1,
2203 to_self_delay: self.on_local_tx_csv,
2204 output: outp.clone(),
2205 key_derivation_params: self.keys.key_derivation_params(),
2206 remote_revocation_pubkey: broadcasted_local_revokable_script.2.clone(),
2210 } else if self.remote_payment_script == outp.script_pubkey {
2211 spendable_output = Some(SpendableOutputDescriptor::StaticOutputRemotePayment {
2212 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2213 output: outp.clone(),
2214 key_derivation_params: self.keys.key_derivation_params(),
2217 } else if outp.script_pubkey == self.shutdown_script {
2218 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2219 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2220 output: outp.clone(),
2224 if let Some(spendable_output) = spendable_output {
2225 log_trace!(logger, "Maturing {} until {}", log_spendable!(spendable_output), height + ANTI_REORG_DELAY - 1);
2226 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2227 hash_map::Entry::Occupied(mut entry) => {
2228 let e = entry.get_mut();
2229 e.push(OnchainEvent::MaturingOutput { descriptor: spendable_output });
2231 hash_map::Entry::Vacant(entry) => {
2232 entry.insert(vec![OnchainEvent::MaturingOutput { descriptor: spendable_output }]);
2239 const MAX_ALLOC_SIZE: usize = 64*1024;
2241 impl<ChanSigner: ChannelKeys + Readable> Readable for (BlockHash, ChannelMonitor<ChanSigner>) {
2242 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
2243 macro_rules! unwrap_obj {
2247 Err(_) => return Err(DecodeError::InvalidValue),
2252 let _ver: u8 = Readable::read(reader)?;
2253 let min_ver: u8 = Readable::read(reader)?;
2254 if min_ver > SERIALIZATION_VERSION {
2255 return Err(DecodeError::UnknownVersion);
2258 let latest_update_id: u64 = Readable::read(reader)?;
2259 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
2261 let destination_script = Readable::read(reader)?;
2262 let broadcasted_local_revokable_script = match <u8 as Readable>::read(reader)? {
2264 let revokable_address = Readable::read(reader)?;
2265 let per_commitment_point = Readable::read(reader)?;
2266 let revokable_script = Readable::read(reader)?;
2267 Some((revokable_address, per_commitment_point, revokable_script))
2270 _ => return Err(DecodeError::InvalidValue),
2272 let remote_payment_script = Readable::read(reader)?;
2273 let shutdown_script = Readable::read(reader)?;
2275 let keys = Readable::read(reader)?;
2276 // Technically this can fail and serialize fail a round-trip, but only for serialization of
2277 // barely-init'd ChannelMonitors that we can't do anything with.
2278 let outpoint = OutPoint {
2279 txid: Readable::read(reader)?,
2280 index: Readable::read(reader)?,
2282 let funding_info = (outpoint, Readable::read(reader)?);
2283 let current_remote_commitment_txid = Readable::read(reader)?;
2284 let prev_remote_commitment_txid = Readable::read(reader)?;
2286 let remote_tx_cache = Readable::read(reader)?;
2287 let funding_redeemscript = Readable::read(reader)?;
2288 let channel_value_satoshis = Readable::read(reader)?;
2290 let their_cur_revocation_points = {
2291 let first_idx = <U48 as Readable>::read(reader)?.0;
2295 let first_point = Readable::read(reader)?;
2296 let second_point_slice: [u8; 33] = Readable::read(reader)?;
2297 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
2298 Some((first_idx, first_point, None))
2300 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
2305 let on_local_tx_csv: u16 = Readable::read(reader)?;
2307 let commitment_secrets = Readable::read(reader)?;
2309 macro_rules! read_htlc_in_commitment {
2312 let offered: bool = Readable::read(reader)?;
2313 let amount_msat: u64 = Readable::read(reader)?;
2314 let cltv_expiry: u32 = Readable::read(reader)?;
2315 let payment_hash: PaymentHash = Readable::read(reader)?;
2316 let transaction_output_index: Option<u32> = Readable::read(reader)?;
2318 HTLCOutputInCommitment {
2319 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
2325 let remote_claimable_outpoints_len: u64 = Readable::read(reader)?;
2326 let mut remote_claimable_outpoints = HashMap::with_capacity(cmp::min(remote_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
2327 for _ in 0..remote_claimable_outpoints_len {
2328 let txid: Txid = Readable::read(reader)?;
2329 let htlcs_count: u64 = Readable::read(reader)?;
2330 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
2331 for _ in 0..htlcs_count {
2332 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
2334 if let Some(_) = remote_claimable_outpoints.insert(txid, htlcs) {
2335 return Err(DecodeError::InvalidValue);
2339 let remote_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
2340 let mut remote_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(remote_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
2341 for _ in 0..remote_commitment_txn_on_chain_len {
2342 let txid: Txid = Readable::read(reader)?;
2343 let commitment_number = <U48 as Readable>::read(reader)?.0;
2344 let outputs_count = <u64 as Readable>::read(reader)?;
2345 let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 8));
2346 for _ in 0..outputs_count {
2347 outputs.push(Readable::read(reader)?);
2349 if let Some(_) = remote_commitment_txn_on_chain.insert(txid, (commitment_number, outputs)) {
2350 return Err(DecodeError::InvalidValue);
2354 let remote_hash_commitment_number_len: u64 = Readable::read(reader)?;
2355 let mut remote_hash_commitment_number = HashMap::with_capacity(cmp::min(remote_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
2356 for _ in 0..remote_hash_commitment_number_len {
2357 let payment_hash: PaymentHash = Readable::read(reader)?;
2358 let commitment_number = <U48 as Readable>::read(reader)?.0;
2359 if let Some(_) = remote_hash_commitment_number.insert(payment_hash, commitment_number) {
2360 return Err(DecodeError::InvalidValue);
2364 macro_rules! read_local_tx {
2367 let txid = Readable::read(reader)?;
2368 let revocation_key = Readable::read(reader)?;
2369 let a_htlc_key = Readable::read(reader)?;
2370 let b_htlc_key = Readable::read(reader)?;
2371 let delayed_payment_key = Readable::read(reader)?;
2372 let per_commitment_point = Readable::read(reader)?;
2373 let feerate_per_kw: u32 = Readable::read(reader)?;
2375 let htlcs_len: u64 = Readable::read(reader)?;
2376 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_len as usize, MAX_ALLOC_SIZE / 128));
2377 for _ in 0..htlcs_len {
2378 let htlc = read_htlc_in_commitment!();
2379 let sigs = match <u8 as Readable>::read(reader)? {
2381 1 => Some(Readable::read(reader)?),
2382 _ => return Err(DecodeError::InvalidValue),
2384 htlcs.push((htlc, sigs, Readable::read(reader)?));
2389 revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, per_commitment_point, feerate_per_kw,
2396 let prev_local_signed_commitment_tx = match <u8 as Readable>::read(reader)? {
2399 Some(read_local_tx!())
2401 _ => return Err(DecodeError::InvalidValue),
2403 let current_local_commitment_tx = read_local_tx!();
2405 let current_remote_commitment_number = <U48 as Readable>::read(reader)?.0;
2406 let current_local_commitment_number = <U48 as Readable>::read(reader)?.0;
2408 let payment_preimages_len: u64 = Readable::read(reader)?;
2409 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
2410 for _ in 0..payment_preimages_len {
2411 let preimage: PaymentPreimage = Readable::read(reader)?;
2412 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2413 if let Some(_) = payment_preimages.insert(hash, preimage) {
2414 return Err(DecodeError::InvalidValue);
2418 let pending_htlcs_updated_len: u64 = Readable::read(reader)?;
2419 let mut pending_htlcs_updated = Vec::with_capacity(cmp::min(pending_htlcs_updated_len as usize, MAX_ALLOC_SIZE / (32 + 8*3)));
2420 for _ in 0..pending_htlcs_updated_len {
2421 pending_htlcs_updated.push(Readable::read(reader)?);
2424 let pending_events_len: u64 = Readable::read(reader)?;
2425 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<events::Event>()));
2426 for _ in 0..pending_events_len {
2427 if let Some(event) = MaybeReadable::read(reader)? {
2428 pending_events.push(event);
2432 let last_block_hash: BlockHash = Readable::read(reader)?;
2434 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
2435 let mut onchain_events_waiting_threshold_conf = HashMap::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
2436 for _ in 0..waiting_threshold_conf_len {
2437 let height_target = Readable::read(reader)?;
2438 let events_len: u64 = Readable::read(reader)?;
2439 let mut events = Vec::with_capacity(cmp::min(events_len as usize, MAX_ALLOC_SIZE / 128));
2440 for _ in 0..events_len {
2441 let ev = match <u8 as Readable>::read(reader)? {
2443 let htlc_source = Readable::read(reader)?;
2444 let hash = Readable::read(reader)?;
2445 OnchainEvent::HTLCUpdate {
2446 htlc_update: (htlc_source, hash)
2450 let descriptor = Readable::read(reader)?;
2451 OnchainEvent::MaturingOutput {
2455 _ => return Err(DecodeError::InvalidValue),
2459 onchain_events_waiting_threshold_conf.insert(height_target, events);
2462 let outputs_to_watch_len: u64 = Readable::read(reader)?;
2463 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>>())));
2464 for _ in 0..outputs_to_watch_len {
2465 let txid = Readable::read(reader)?;
2466 let outputs_len: u64 = Readable::read(reader)?;
2467 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Script>()));
2468 for _ in 0..outputs_len {
2469 outputs.push(Readable::read(reader)?);
2471 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
2472 return Err(DecodeError::InvalidValue);
2475 let onchain_tx_handler = Readable::read(reader)?;
2477 let lockdown_from_offchain = Readable::read(reader)?;
2478 let local_tx_signed = Readable::read(reader)?;
2480 Ok((last_block_hash.clone(), ChannelMonitor {
2482 commitment_transaction_number_obscure_factor,
2485 broadcasted_local_revokable_script,
2486 remote_payment_script,
2491 current_remote_commitment_txid,
2492 prev_remote_commitment_txid,
2495 funding_redeemscript,
2496 channel_value_satoshis,
2497 their_cur_revocation_points,
2502 remote_claimable_outpoints,
2503 remote_commitment_txn_on_chain,
2504 remote_hash_commitment_number,
2506 prev_local_signed_commitment_tx,
2507 current_local_commitment_tx,
2508 current_remote_commitment_number,
2509 current_local_commitment_number,
2512 pending_htlcs_updated,
2515 onchain_events_waiting_threshold_conf,
2520 lockdown_from_offchain,
2524 secp_ctx: Secp256k1::new(),
2531 use bitcoin::blockdata::script::{Script, Builder};
2532 use bitcoin::blockdata::opcodes;
2533 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, SigHashType};
2534 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
2535 use bitcoin::util::bip143;
2536 use bitcoin::hashes::Hash;
2537 use bitcoin::hashes::sha256::Hash as Sha256;
2538 use bitcoin::hashes::hex::FromHex;
2539 use bitcoin::hash_types::Txid;
2541 use chain::transaction::OutPoint;
2542 use ln::channelmanager::{PaymentPreimage, PaymentHash};
2543 use ln::channelmonitor::ChannelMonitor;
2544 use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
2546 use ln::chan_utils::{HTLCOutputInCommitment, LocalCommitmentTransaction};
2547 use util::test_utils::TestLogger;
2548 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
2549 use bitcoin::secp256k1::Secp256k1;
2551 use chain::keysinterface::InMemoryChannelKeys;
2554 fn test_prune_preimages() {
2555 let secp_ctx = Secp256k1::new();
2556 let logger = Arc::new(TestLogger::new());
2558 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
2559 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2561 let mut preimages = Vec::new();
2564 let preimage = PaymentPreimage([i; 32]);
2565 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2566 preimages.push((preimage, hash));
2570 macro_rules! preimages_slice_to_htlc_outputs {
2571 ($preimages_slice: expr) => {
2573 let mut res = Vec::new();
2574 for (idx, preimage) in $preimages_slice.iter().enumerate() {
2575 res.push((HTLCOutputInCommitment {
2579 payment_hash: preimage.1.clone(),
2580 transaction_output_index: Some(idx as u32),
2587 macro_rules! preimages_to_local_htlcs {
2588 ($preimages_slice: expr) => {
2590 let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2591 let res: Vec<_> = inp.drain(..).map(|e| { (e.0, None, e.1) }).collect();
2597 macro_rules! test_preimages_exist {
2598 ($preimages_slice: expr, $monitor: expr) => {
2599 for preimage in $preimages_slice {
2600 assert!($monitor.payment_preimages.contains_key(&preimage.1));
2605 let keys = InMemoryChannelKeys::new(
2607 SecretKey::from_slice(&[41; 32]).unwrap(),
2608 SecretKey::from_slice(&[41; 32]).unwrap(),
2609 SecretKey::from_slice(&[41; 32]).unwrap(),
2610 SecretKey::from_slice(&[41; 32]).unwrap(),
2611 SecretKey::from_slice(&[41; 32]).unwrap(),
2617 // Prune with one old state and a local commitment tx holding a few overlaps with the
2619 let mut monitor = ChannelMonitor::new(keys,
2620 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()), 0, &Script::new(),
2621 (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
2622 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
2623 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
2624 10, Script::new(), 46, 0, LocalCommitmentTransaction::dummy());
2626 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..10])).unwrap();
2627 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
2628 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
2629 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
2630 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
2631 for &(ref preimage, ref hash) in preimages.iter() {
2632 monitor.provide_payment_preimage(hash, preimage);
2635 // Now provide a secret, pruning preimages 10-15
2636 let mut secret = [0; 32];
2637 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2638 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2639 assert_eq!(monitor.payment_preimages.len(), 15);
2640 test_preimages_exist!(&preimages[0..10], monitor);
2641 test_preimages_exist!(&preimages[15..20], monitor);
2643 // Now provide a further secret, pruning preimages 15-17
2644 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2645 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2646 assert_eq!(monitor.payment_preimages.len(), 13);
2647 test_preimages_exist!(&preimages[0..10], monitor);
2648 test_preimages_exist!(&preimages[17..20], monitor);
2650 // Now update local commitment tx info, pruning only element 18 as we still care about the
2651 // previous commitment tx's preimages too
2652 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..5])).unwrap();
2653 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2654 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2655 assert_eq!(monitor.payment_preimages.len(), 12);
2656 test_preimages_exist!(&preimages[0..10], monitor);
2657 test_preimages_exist!(&preimages[18..20], monitor);
2659 // But if we do it again, we'll prune 5-10
2660 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..3])).unwrap();
2661 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2662 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2663 assert_eq!(monitor.payment_preimages.len(), 5);
2664 test_preimages_exist!(&preimages[0..5], monitor);
2668 fn test_claim_txn_weight_computation() {
2669 // We test Claim txn weight, knowing that we want expected weigth and
2670 // not actual case to avoid sigs and time-lock delays hell variances.
2672 let secp_ctx = Secp256k1::new();
2673 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
2674 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
2675 let mut sum_actual_sigs = 0;
2677 macro_rules! sign_input {
2678 ($sighash_parts: expr, $input: expr, $idx: expr, $amount: expr, $input_type: expr, $sum_actual_sigs: expr) => {
2679 let htlc = HTLCOutputInCommitment {
2680 offered: if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::OfferedHTLC { true } else { false },
2682 cltv_expiry: 2 << 16,
2683 payment_hash: PaymentHash([1; 32]),
2684 transaction_output_index: Some($idx),
2686 let redeem_script = if *$input_type == InputDescriptors::RevokedOutput { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &pubkey, &pubkey, &pubkey) };
2687 let sighash = hash_to_message!(&$sighash_parts.sighash_all(&$input, &redeem_script, $amount)[..]);
2688 let sig = secp_ctx.sign(&sighash, &privkey);
2689 $input.witness.push(sig.serialize_der().to_vec());
2690 $input.witness[0].push(SigHashType::All as u8);
2691 sum_actual_sigs += $input.witness[0].len();
2692 if *$input_type == InputDescriptors::RevokedOutput {
2693 $input.witness.push(vec!(1));
2694 } else if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::RevokedReceivedHTLC {
2695 $input.witness.push(pubkey.clone().serialize().to_vec());
2696 } else if *$input_type == InputDescriptors::ReceivedHTLC {
2697 $input.witness.push(vec![0]);
2699 $input.witness.push(PaymentPreimage([1; 32]).0.to_vec());
2701 $input.witness.push(redeem_script.into_bytes());
2702 println!("witness[0] {}", $input.witness[0].len());
2703 println!("witness[1] {}", $input.witness[1].len());
2704 println!("witness[2] {}", $input.witness[2].len());
2708 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
2709 let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
2711 // Justice tx with 1 to_local, 2 revoked offered HTLCs, 1 revoked received HTLCs
2712 let mut claim_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2714 claim_tx.input.push(TxIn {
2715 previous_output: BitcoinOutPoint {
2719 script_sig: Script::new(),
2720 sequence: 0xfffffffd,
2721 witness: Vec::new(),
2724 claim_tx.output.push(TxOut {
2725 script_pubkey: script_pubkey.clone(),
2728 let base_weight = claim_tx.get_weight();
2729 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2730 let inputs_des = vec![InputDescriptors::RevokedOutput, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedReceivedHTLC];
2731 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2732 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2734 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));
2736 // Claim tx with 1 offered HTLCs, 3 received HTLCs
2737 claim_tx.input.clear();
2738 sum_actual_sigs = 0;
2740 claim_tx.input.push(TxIn {
2741 previous_output: BitcoinOutPoint {
2745 script_sig: Script::new(),
2746 sequence: 0xfffffffd,
2747 witness: Vec::new(),
2750 let base_weight = claim_tx.get_weight();
2751 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2752 let inputs_des = vec![InputDescriptors::OfferedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC];
2753 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2754 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2756 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));
2758 // Justice tx with 1 revoked HTLC-Success tx output
2759 claim_tx.input.clear();
2760 sum_actual_sigs = 0;
2761 claim_tx.input.push(TxIn {
2762 previous_output: BitcoinOutPoint {
2766 script_sig: Script::new(),
2767 sequence: 0xfffffffd,
2768 witness: Vec::new(),
2770 let base_weight = claim_tx.get_weight();
2771 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2772 let inputs_des = vec![InputDescriptors::RevokedOutput];
2773 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2774 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2776 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));
2779 // Further testing is done in the ChannelManager integration tests.