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 latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date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, RemoteTxCache};
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 /// Simple trait indicating ability to track a set of ChannelMonitors and multiplex events between
153 /// them. Generally should be implemented by keeping a local SimpleManyChannelMonitor and passing
154 /// events to it, while also taking any add/update_monitor events and passing them to some remote
157 /// In general, you must always have at least one local copy in memory, which must never fail to
158 /// update (as it is responsible for broadcasting the latest state in case the channel is closed),
159 /// and then persist it to various on-disk locations. If, for some reason, the in-memory copy fails
160 /// to update (eg out-of-memory or some other condition), you must immediately shut down without
161 /// taking any further action such as writing the current state to disk. This should likely be
162 /// accomplished via panic!() or abort().
164 /// Note that any updates to a channel's monitor *must* be applied to each instance of the
165 /// channel's monitor everywhere (including remote watchtowers) *before* this function returns. If
166 /// an update occurs and a remote watchtower is left with old state, it may broadcast transactions
167 /// which we have revoked, allowing our counterparty to claim all funds in the channel!
169 /// User needs to notify implementors of ManyChannelMonitor when a new block is connected or
170 /// disconnected using their `block_connected` and `block_disconnected` methods. However, rather
171 /// than calling these methods directly, the user should register implementors as listeners to the
172 /// BlockNotifier and call the BlockNotifier's `block_(dis)connected` methods, which will notify
173 /// all registered listeners in one go.
174 pub trait ManyChannelMonitor<ChanSigner: ChannelKeys>: Send + Sync {
175 /// Adds a monitor for the given `funding_txo`.
177 /// Implementer must also ensure that the funding_txo txid *and* outpoint are registered with
178 /// any relevant ChainWatchInterfaces such that the provided monitor receives block_connected
179 /// callbacks with the funding transaction, or any spends of it.
181 /// Further, the implementer must also ensure that each output returned in
182 /// monitor.get_outputs_to_watch() is registered to ensure that the provided monitor learns about
183 /// any spends of any of the outputs.
185 /// Any spends of outputs which should have been registered which aren't passed to
186 /// ChannelMonitors via block_connected may result in FUNDS LOSS.
187 fn add_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor<ChanSigner>) -> Result<(), ChannelMonitorUpdateErr>;
189 /// Updates a monitor for the given `funding_txo`.
191 /// Implementer must also ensure that the funding_txo txid *and* outpoint are registered with
192 /// any relevant ChainWatchInterfaces such that the provided monitor receives block_connected
193 /// callbacks with the funding transaction, or any spends of it.
195 /// Further, the implementer must also ensure that each output returned in
196 /// monitor.get_watch_outputs() is registered to ensure that the provided monitor learns about
197 /// any spends of any of the outputs.
199 /// Any spends of outputs which should have been registered which aren't passed to
200 /// ChannelMonitors via block_connected may result in FUNDS LOSS.
201 fn update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr>;
203 /// Used by ChannelManager to get list of HTLC resolved onchain and which needed to be updated
204 /// with success or failure.
206 /// You should probably just call through to
207 /// ChannelMonitor::get_and_clear_pending_htlcs_updated() for each ChannelMonitor and return
209 fn get_and_clear_pending_htlcs_updated(&self) -> Vec<HTLCUpdate>;
212 /// A simple implementation of a ManyChannelMonitor and ChainListener. Can be used to create a
213 /// watchtower or watch our own channels.
215 /// Note that you must provide your own key by which to refer to channels.
217 /// If you're accepting remote monitors (ie are implementing a watchtower), you must verify that
218 /// users cannot overwrite a given channel by providing a duplicate key. ie you should probably
219 /// index by a PublicKey which is required to sign any updates.
221 /// If you're using this for local monitoring of your own channels, you probably want to use
222 /// `OutPoint` as the key, which will give you a ManyChannelMonitor implementation.
223 pub struct SimpleManyChannelMonitor<Key, ChanSigner: ChannelKeys, T: Deref, F: Deref, L: Deref, C: Deref>
224 where T::Target: BroadcasterInterface,
225 F::Target: FeeEstimator,
227 C::Target: ChainWatchInterface,
229 #[cfg(test)] // Used in ChannelManager tests to manipulate channels directly
230 pub monitors: Mutex<HashMap<Key, ChannelMonitor<ChanSigner>>>,
232 monitors: Mutex<HashMap<Key, ChannelMonitor<ChanSigner>>>,
239 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>
240 ChainListener for SimpleManyChannelMonitor<Key, ChanSigner, T, F, L, C>
241 where T::Target: BroadcasterInterface,
242 F::Target: FeeEstimator,
244 C::Target: ChainWatchInterface,
246 fn block_connected(&self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], _indexes_of_txn_matched: &[u32]) {
247 let block_hash = header.bitcoin_hash();
249 let mut monitors = self.monitors.lock().unwrap();
250 for monitor in monitors.values_mut() {
251 let txn_outputs = monitor.block_connected(txn_matched, height, &block_hash, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
253 for (ref txid, ref outputs) in txn_outputs {
254 for (idx, output) in outputs.iter().enumerate() {
255 self.chain_monitor.install_watch_outpoint((txid.clone(), idx as u32), &output.script_pubkey);
262 fn block_disconnected(&self, header: &BlockHeader, disconnected_height: u32) {
263 let block_hash = header.bitcoin_hash();
264 let mut monitors = self.monitors.lock().unwrap();
265 for monitor in monitors.values_mut() {
266 monitor.block_disconnected(disconnected_height, &block_hash, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
271 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>
272 where T::Target: BroadcasterInterface,
273 F::Target: FeeEstimator,
275 C::Target: ChainWatchInterface,
277 /// Creates a new object which can be used to monitor several channels given the chain
278 /// interface with which to register to receive notifications.
279 pub fn new(chain_monitor: C, broadcaster: T, logger: L, feeest: F) -> SimpleManyChannelMonitor<Key, ChanSigner, T, F, L, C> {
280 let res = SimpleManyChannelMonitor {
281 monitors: Mutex::new(HashMap::new()),
285 fee_estimator: feeest,
291 /// Adds or updates the monitor which monitors the channel referred to by the given key.
292 pub fn add_monitor_by_key(&self, key: Key, monitor: ChannelMonitor<ChanSigner>) -> Result<(), MonitorUpdateError> {
293 let mut monitors = self.monitors.lock().unwrap();
294 let entry = match monitors.entry(key) {
295 hash_map::Entry::Occupied(_) => return Err(MonitorUpdateError("Channel monitor for given key is already present")),
296 hash_map::Entry::Vacant(e) => e,
298 log_trace!(self.logger, "Got new Channel Monitor for channel {}", log_bytes!(monitor.funding_info.0.to_channel_id()[..]));
299 self.chain_monitor.install_watch_tx(&monitor.funding_info.0.txid, &monitor.funding_info.1);
300 self.chain_monitor.install_watch_outpoint((monitor.funding_info.0.txid, monitor.funding_info.0.index as u32), &monitor.funding_info.1);
301 for (txid, outputs) in monitor.get_outputs_to_watch().iter() {
302 for (idx, script) in outputs.iter().enumerate() {
303 self.chain_monitor.install_watch_outpoint((*txid, idx as u32), script);
306 entry.insert(monitor);
310 /// Updates the monitor which monitors the channel referred to by the given key.
311 pub fn update_monitor_by_key(&self, key: Key, update: ChannelMonitorUpdate) -> Result<(), MonitorUpdateError> {
312 let mut monitors = self.monitors.lock().unwrap();
313 match monitors.get_mut(&key) {
314 Some(orig_monitor) => {
315 log_trace!(self.logger, "Updating Channel Monitor for channel {}", log_funding_info!(orig_monitor));
316 orig_monitor.update_monitor(update, &self.broadcaster, &self.logger)
318 None => Err(MonitorUpdateError("No such monitor registered"))
323 impl<ChanSigner: ChannelKeys, T: Deref + Sync + Send, F: Deref + Sync + Send, L: Deref + Sync + Send, C: Deref + Sync + Send> ManyChannelMonitor<ChanSigner> for SimpleManyChannelMonitor<OutPoint, ChanSigner, T, F, L, C>
324 where T::Target: BroadcasterInterface,
325 F::Target: FeeEstimator,
327 C::Target: ChainWatchInterface,
329 fn add_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor<ChanSigner>) -> Result<(), ChannelMonitorUpdateErr> {
330 match self.add_monitor_by_key(funding_txo, monitor) {
332 Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
336 fn update_monitor(&self, funding_txo: OutPoint, update: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr> {
337 match self.update_monitor_by_key(funding_txo, update) {
339 Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
343 fn get_and_clear_pending_htlcs_updated(&self) -> Vec<HTLCUpdate> {
344 let mut pending_htlcs_updated = Vec::new();
345 for chan in self.monitors.lock().unwrap().values_mut() {
346 pending_htlcs_updated.append(&mut chan.get_and_clear_pending_htlcs_updated());
348 pending_htlcs_updated
352 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>
353 where T::Target: BroadcasterInterface,
354 F::Target: FeeEstimator,
356 C::Target: ChainWatchInterface,
358 fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
359 let mut pending_events = Vec::new();
360 for chan in self.monitors.lock().unwrap().values_mut() {
361 pending_events.append(&mut chan.get_and_clear_pending_events());
367 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
368 /// instead claiming it in its own individual transaction.
369 pub(crate) const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
370 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
371 /// HTLC-Success transaction.
372 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
373 /// transaction confirmed (and we use it in a few more, equivalent, places).
374 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 6;
375 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
376 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
377 /// copies of ChannelMonitors, including watchtowers). We could enforce the contract by failing
378 /// at CLTV expiration height but giving a grace period to our peer may be profitable for us if he
379 /// can provide an over-late preimage. Nevertheless, grace period has to be accounted in our
380 /// CLTV_EXPIRY_DELTA to be secure. Following this policy we may decrease the rate of channel failures
381 /// due to expiration but increase the cost of funds being locked longuer in case of failure.
382 /// This delay also cover a low-power peer being slow to process blocks and so being behind us on
383 /// accurate block height.
384 /// In case of onchain failure to be pass backward we may see the last block of ANTI_REORG_DELAY
385 /// with at worst this delay, so we are not only using this value as a mercy for them but also
386 /// us as a safeguard to delay with enough time.
387 pub(crate) const LATENCY_GRACE_PERIOD_BLOCKS: u32 = 3;
388 /// Number of blocks we wait on seeing a HTLC output being solved before we fail corresponding inbound
389 /// HTLCs. This prevents us from failing backwards and then getting a reorg resulting in us losing money.
390 /// We use also this delay to be sure we can remove our in-flight claim txn from bump candidates buffer.
391 /// It may cause spurrious generation of bumped claim txn but that's allright given the outpoint is already
392 /// solved by a previous claim tx. What we want to avoid is reorg evicting our claim tx and us not
393 /// keeping bumping another claim tx to solve the outpoint.
394 pub(crate) const ANTI_REORG_DELAY: u32 = 6;
395 /// Number of blocks before confirmation at which we fail back an un-relayed HTLC or at which we
396 /// refuse to accept a new HTLC.
398 /// This is used for a few separate purposes:
399 /// 1) if we've received an MPP HTLC to us and it expires within this many blocks and we are
400 /// waiting on additional parts (or waiting on the preimage for any HTLC from the user), we will
402 /// 2) if we receive an HTLC within this many blocks of its expiry (plus one to avoid a race
403 /// condition with the above), we will fail this HTLC without telling the user we received it,
404 /// 3) if we are waiting on a connection or a channel state update to send an HTLC to a peer, and
405 /// that HTLC expires within this many blocks, we will simply fail the HTLC instead.
407 /// (1) is all about protecting us - we need enough time to update the channel state before we hit
408 /// CLTV_CLAIM_BUFFER, at which point we'd go on chain to claim the HTLC with the preimage.
410 /// (2) is the same, but with an additional buffer to avoid accepting an HTLC which is immediately
411 /// in a race condition between the user connecting a block (which would fail it) and the user
412 /// providing us the preimage (which would claim it).
414 /// (3) is about our counterparty - we don't want to relay an HTLC to a counterparty when they may
415 /// end up force-closing the channel on us to claim it.
416 pub(crate) const HTLC_FAIL_BACK_BUFFER: u32 = CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS;
418 #[derive(Clone, PartialEq)]
419 struct LocalSignedTx {
420 /// txid of the transaction in tx, just used to make comparison faster
422 revocation_key: PublicKey,
423 a_htlc_key: PublicKey,
424 b_htlc_key: PublicKey,
425 delayed_payment_key: PublicKey,
426 per_commitment_point: PublicKey,
428 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
431 /// When ChannelMonitor discovers an onchain outpoint being a step of a channel and that it needs
432 /// to generate a tx to push channel state forward, we cache outpoint-solving tx material to build
433 /// a new bumped one in case of lenghty confirmation delay
434 #[derive(Clone, PartialEq)]
435 pub(crate) enum InputMaterial {
437 per_commitment_point: PublicKey,
438 remote_delayed_payment_base_key: PublicKey,
439 remote_htlc_base_key: PublicKey,
440 per_commitment_key: SecretKey,
441 input_descriptor: InputDescriptors,
443 htlc: Option<HTLCOutputInCommitment>
446 per_commitment_point: PublicKey,
447 remote_delayed_payment_base_key: PublicKey,
448 remote_htlc_base_key: PublicKey,
449 preimage: Option<PaymentPreimage>,
450 htlc: HTLCOutputInCommitment
453 preimage: Option<PaymentPreimage>,
457 funding_redeemscript: Script,
461 impl Writeable for InputMaterial {
462 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
464 &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} => {
465 writer.write_all(&[0; 1])?;
466 per_commitment_point.write(writer)?;
467 remote_delayed_payment_base_key.write(writer)?;
468 remote_htlc_base_key.write(writer)?;
469 writer.write_all(&per_commitment_key[..])?;
470 input_descriptor.write(writer)?;
471 writer.write_all(&byte_utils::be64_to_array(*amount))?;
474 &InputMaterial::RemoteHTLC { ref per_commitment_point, ref remote_delayed_payment_base_key, ref remote_htlc_base_key, ref preimage, ref htlc} => {
475 writer.write_all(&[1; 1])?;
476 per_commitment_point.write(writer)?;
477 remote_delayed_payment_base_key.write(writer)?;
478 remote_htlc_base_key.write(writer)?;
479 preimage.write(writer)?;
482 &InputMaterial::LocalHTLC { ref preimage, ref amount } => {
483 writer.write_all(&[2; 1])?;
484 preimage.write(writer)?;
485 writer.write_all(&byte_utils::be64_to_array(*amount))?;
487 &InputMaterial::Funding { ref funding_redeemscript } => {
488 writer.write_all(&[3; 1])?;
489 funding_redeemscript.write(writer)?;
496 impl Readable for InputMaterial {
497 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
498 let input_material = match <u8 as Readable>::read(reader)? {
500 let per_commitment_point = Readable::read(reader)?;
501 let remote_delayed_payment_base_key = Readable::read(reader)?;
502 let remote_htlc_base_key = Readable::read(reader)?;
503 let per_commitment_key = Readable::read(reader)?;
504 let input_descriptor = Readable::read(reader)?;
505 let amount = Readable::read(reader)?;
506 let htlc = Readable::read(reader)?;
507 InputMaterial::Revoked {
508 per_commitment_point,
509 remote_delayed_payment_base_key,
510 remote_htlc_base_key,
518 let per_commitment_point = Readable::read(reader)?;
519 let remote_delayed_payment_base_key = Readable::read(reader)?;
520 let remote_htlc_base_key = Readable::read(reader)?;
521 let preimage = Readable::read(reader)?;
522 let htlc = Readable::read(reader)?;
523 InputMaterial::RemoteHTLC {
524 per_commitment_point,
525 remote_delayed_payment_base_key,
526 remote_htlc_base_key,
532 let preimage = Readable::read(reader)?;
533 let amount = Readable::read(reader)?;
534 InputMaterial::LocalHTLC {
540 InputMaterial::Funding {
541 funding_redeemscript: Readable::read(reader)?,
544 _ => return Err(DecodeError::InvalidValue),
550 /// ClaimRequest is a descriptor structure to communicate between detection
551 /// and reaction module. They are generated by ChannelMonitor while parsing
552 /// onchain txn leaked from a channel and handed over to OnchainTxHandler which
553 /// is responsible for opportunistic aggregation, selecting and enforcing
554 /// bumping logic, building and signing transactions.
555 pub(crate) struct ClaimRequest {
556 // Block height before which claiming is exclusive to one party,
557 // after reaching it, claiming may be contentious.
558 pub(crate) absolute_timelock: u32,
559 // Timeout tx must have nLocktime set which means aggregating multiple
560 // ones must take the higher nLocktime among them to satisfy all of them.
561 // Sadly it has few pitfalls, a) it takes longuer to get fund back b) CLTV_DELTA
562 // of a sooner-HTLC could be swallowed by the highest nLocktime of the HTLC set.
563 // Do simplify we mark them as non-aggregable.
564 pub(crate) aggregable: bool,
565 // Basic bitcoin outpoint (txid, vout)
566 pub(crate) outpoint: BitcoinOutPoint,
567 // Following outpoint type, set of data needed to generate transaction digest
568 // and satisfy witness program.
569 pub(crate) witness_data: InputMaterial
572 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
573 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
574 #[derive(Clone, PartialEq)]
576 /// HTLC output getting solved by a timeout, at maturation we pass upstream payment source information to solve
577 /// inbound HTLC in backward channel. Note, in case of preimage, we pass info to upstream without delay as we can
578 /// only win from it, so it's never an OnchainEvent
580 htlc_update: (HTLCSource, PaymentHash),
583 descriptor: SpendableOutputDescriptor,
587 const SERIALIZATION_VERSION: u8 = 1;
588 const MIN_SERIALIZATION_VERSION: u8 = 1;
590 #[cfg_attr(test, derive(PartialEq))]
592 pub(super) enum ChannelMonitorUpdateStep {
593 LatestLocalCommitmentTXInfo {
594 commitment_tx: LocalCommitmentTransaction,
595 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
597 LatestRemoteCommitmentTXInfo {
598 unsigned_commitment_tx: Transaction, // TODO: We should actually only need the txid here
599 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
600 commitment_number: u64,
601 their_revocation_point: PublicKey,
604 payment_preimage: PaymentPreimage,
610 /// Used to indicate that the no future updates will occur, and likely that the latest local
611 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
613 /// If set to false, we shouldn't broadcast the latest local commitment transaction as we
614 /// think we've fallen behind!
615 should_broadcast: bool,
619 impl Writeable for ChannelMonitorUpdateStep {
620 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
622 &ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { ref commitment_tx, ref htlc_outputs } => {
624 commitment_tx.write(w)?;
625 (htlc_outputs.len() as u64).write(w)?;
626 for &(ref output, ref signature, ref source) in htlc_outputs.iter() {
632 &ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { ref unsigned_commitment_tx, ref htlc_outputs, ref commitment_number, ref their_revocation_point } => {
634 unsigned_commitment_tx.write(w)?;
635 commitment_number.write(w)?;
636 their_revocation_point.write(w)?;
637 (htlc_outputs.len() as u64).write(w)?;
638 for &(ref output, ref source) in htlc_outputs.iter() {
640 source.as_ref().map(|b| b.as_ref()).write(w)?;
643 &ChannelMonitorUpdateStep::PaymentPreimage { ref payment_preimage } => {
645 payment_preimage.write(w)?;
647 &ChannelMonitorUpdateStep::CommitmentSecret { ref idx, ref secret } => {
652 &ChannelMonitorUpdateStep::ChannelForceClosed { ref should_broadcast } => {
654 should_broadcast.write(w)?;
660 impl Readable for ChannelMonitorUpdateStep {
661 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
662 match Readable::read(r)? {
664 Ok(ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo {
665 commitment_tx: Readable::read(r)?,
667 let len: u64 = Readable::read(r)?;
668 let mut res = Vec::new();
670 res.push((Readable::read(r)?, Readable::read(r)?, Readable::read(r)?));
677 Ok(ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo {
678 unsigned_commitment_tx: Readable::read(r)?,
679 commitment_number: Readable::read(r)?,
680 their_revocation_point: Readable::read(r)?,
682 let len: u64 = Readable::read(r)?;
683 let mut res = Vec::new();
685 res.push((Readable::read(r)?, <Option<HTLCSource> as Readable>::read(r)?.map(|o| Box::new(o))));
692 Ok(ChannelMonitorUpdateStep::PaymentPreimage {
693 payment_preimage: Readable::read(r)?,
697 Ok(ChannelMonitorUpdateStep::CommitmentSecret {
698 idx: Readable::read(r)?,
699 secret: Readable::read(r)?,
703 Ok(ChannelMonitorUpdateStep::ChannelForceClosed {
704 should_broadcast: Readable::read(r)?
707 _ => Err(DecodeError::InvalidValue),
712 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
713 /// on-chain transactions to ensure no loss of funds occurs.
715 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
716 /// information and are actively monitoring the chain.
718 /// Pending Events or updated HTLCs which have not yet been read out by
719 /// get_and_clear_pending_htlcs_updated or get_and_clear_pending_events are serialized to disk and
720 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
721 /// gotten are fully handled before re-serializing the new state.
722 pub struct ChannelMonitor<ChanSigner: ChannelKeys> {
723 latest_update_id: u64,
724 commitment_transaction_number_obscure_factor: u64,
726 destination_script: Script,
727 broadcasted_local_revokable_script: Option<(Script, PublicKey, PublicKey)>,
728 remote_payment_script: Script,
729 shutdown_script: Script,
732 funding_info: (OutPoint, Script),
733 current_remote_commitment_txid: Option<Txid>,
734 prev_remote_commitment_txid: Option<Txid>,
736 remote_tx_cache: RemoteTxCache,
737 funding_redeemscript: Script,
738 channel_value_satoshis: u64,
739 // first is the idx of the first of the two revocation points
740 their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
742 our_to_self_delay: u16,
743 their_to_self_delay: u16,
745 commitment_secrets: CounterpartyCommitmentSecrets,
746 remote_claimable_outpoints: HashMap<Txid, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
747 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
748 /// Nor can we figure out their commitment numbers without the commitment transaction they are
749 /// spending. Thus, in order to claim them via revocation key, we track all the remote
750 /// commitment transactions which we find on-chain, mapping them to the commitment number which
751 /// can be used to derive the revocation key and claim the transactions.
752 remote_commitment_txn_on_chain: HashMap<Txid, (u64, Vec<Script>)>,
753 /// Cache used to make pruning of payment_preimages faster.
754 /// Maps payment_hash values to commitment numbers for remote transactions for non-revoked
755 /// remote transactions (ie should remain pretty small).
756 /// Serialized to disk but should generally not be sent to Watchtowers.
757 remote_hash_commitment_number: HashMap<PaymentHash, u64>,
759 // We store two local commitment transactions to avoid any race conditions where we may update
760 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
761 // various monitors for one channel being out of sync, and us broadcasting a local
762 // transaction for which we have deleted claim information on some watchtowers.
763 prev_local_signed_commitment_tx: Option<LocalSignedTx>,
764 current_local_commitment_tx: LocalSignedTx,
766 // Used just for ChannelManager to make sure it has the latest channel data during
768 current_remote_commitment_number: u64,
769 // Used just for ChannelManager to make sure it has the latest channel data during
771 current_local_commitment_number: u64,
773 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
775 pending_htlcs_updated: Vec<HTLCUpdate>,
776 pending_events: Vec<events::Event>,
778 // Used to track onchain events, i.e transactions parts of channels confirmed on chain, on which
779 // we have to take actions once they reach enough confs. Key is a block height timer, i.e we enforce
780 // actions when we receive a block with given height. Actions depend on OnchainEvent type.
781 onchain_events_waiting_threshold_conf: HashMap<u32, Vec<OnchainEvent>>,
783 // If we get serialized out and re-read, we need to make sure that the chain monitoring
784 // interface knows about the TXOs that we want to be notified of spends of. We could probably
785 // be smart and derive them from the above storage fields, but its much simpler and more
786 // Obviously Correct (tm) if we just keep track of them explicitly.
787 outputs_to_watch: HashMap<Txid, Vec<Script>>,
790 pub onchain_tx_handler: OnchainTxHandler<ChanSigner>,
792 onchain_tx_handler: OnchainTxHandler<ChanSigner>,
794 // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
795 // channel has been force-closed. After this is set, no further local commitment transaction
796 // updates may occur, and we panic!() if one is provided.
797 lockdown_from_offchain: bool,
799 // Set once we've signed a local commitment transaction and handed it over to our
800 // OnchainTxHandler. After this is set, no future updates to our local commitment transactions
801 // may occur, and we fail any such monitor updates.
802 local_tx_signed: bool,
804 // We simply modify last_block_hash in Channel's block_connected so that serialization is
805 // consistent but hopefully the users' copy handles block_connected in a consistent way.
806 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
807 // their last_block_hash from its state and not based on updated copies that didn't run through
808 // the full block_connected).
809 pub(crate) last_block_hash: BlockHash,
810 secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
813 #[cfg(any(test, feature = "fuzztarget"))]
814 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
815 /// underlying object
816 impl<ChanSigner: ChannelKeys> PartialEq for ChannelMonitor<ChanSigner> {
817 fn eq(&self, other: &Self) -> bool {
818 if self.latest_update_id != other.latest_update_id ||
819 self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
820 self.destination_script != other.destination_script ||
821 self.broadcasted_local_revokable_script != other.broadcasted_local_revokable_script ||
822 self.remote_payment_script != other.remote_payment_script ||
823 self.keys.pubkeys() != other.keys.pubkeys() ||
824 self.funding_info != other.funding_info ||
825 self.current_remote_commitment_txid != other.current_remote_commitment_txid ||
826 self.prev_remote_commitment_txid != other.prev_remote_commitment_txid ||
827 self.remote_tx_cache != other.remote_tx_cache ||
828 self.funding_redeemscript != other.funding_redeemscript ||
829 self.channel_value_satoshis != other.channel_value_satoshis ||
830 self.their_cur_revocation_points != other.their_cur_revocation_points ||
831 self.our_to_self_delay != other.our_to_self_delay ||
832 self.their_to_self_delay != other.their_to_self_delay ||
833 self.commitment_secrets != other.commitment_secrets ||
834 self.remote_claimable_outpoints != other.remote_claimable_outpoints ||
835 self.remote_commitment_txn_on_chain != other.remote_commitment_txn_on_chain ||
836 self.remote_hash_commitment_number != other.remote_hash_commitment_number ||
837 self.prev_local_signed_commitment_tx != other.prev_local_signed_commitment_tx ||
838 self.current_remote_commitment_number != other.current_remote_commitment_number ||
839 self.current_local_commitment_number != other.current_local_commitment_number ||
840 self.current_local_commitment_tx != other.current_local_commitment_tx ||
841 self.payment_preimages != other.payment_preimages ||
842 self.pending_htlcs_updated != other.pending_htlcs_updated ||
843 self.pending_events.len() != other.pending_events.len() || // We trust events to round-trip properly
844 self.onchain_events_waiting_threshold_conf != other.onchain_events_waiting_threshold_conf ||
845 self.outputs_to_watch != other.outputs_to_watch ||
846 self.lockdown_from_offchain != other.lockdown_from_offchain ||
847 self.local_tx_signed != other.local_tx_signed
856 impl<ChanSigner: ChannelKeys + Writeable> ChannelMonitor<ChanSigner> {
857 /// Writes this monitor into the given writer, suitable for writing to disk.
859 /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
860 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
861 /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
862 /// returned block hash and the the current chain and then reconnecting blocks to get to the
863 /// best chain) upon deserializing the object!
864 pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
865 //TODO: We still write out all the serialization here manually instead of using the fancy
866 //serialization framework we have, we should migrate things over to it.
867 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
868 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
870 self.latest_update_id.write(writer)?;
872 // Set in initial Channel-object creation, so should always be set by now:
873 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
875 self.destination_script.write(writer)?;
876 if let Some(ref broadcasted_local_revokable_script) = self.broadcasted_local_revokable_script {
877 writer.write_all(&[0; 1])?;
878 broadcasted_local_revokable_script.0.write(writer)?;
879 broadcasted_local_revokable_script.1.write(writer)?;
880 broadcasted_local_revokable_script.2.write(writer)?;
882 writer.write_all(&[1; 1])?;
885 self.remote_payment_script.write(writer)?;
886 self.shutdown_script.write(writer)?;
888 self.keys.write(writer)?;
889 writer.write_all(&self.funding_info.0.txid[..])?;
890 writer.write_all(&byte_utils::be16_to_array(self.funding_info.0.index))?;
891 self.funding_info.1.write(writer)?;
892 self.current_remote_commitment_txid.write(writer)?;
893 self.prev_remote_commitment_txid.write(writer)?;
895 self.remote_tx_cache.remote_delayed_payment_base_key.write(writer)?;
896 self.remote_tx_cache.remote_htlc_base_key.write(writer)?;
897 writer.write_all(&byte_utils::be64_to_array(self.remote_tx_cache.per_htlc.len() as u64))?;
898 for (ref txid, ref htlcs) in self.remote_tx_cache.per_htlc.iter() {
899 writer.write_all(&txid[..])?;
900 writer.write_all(&byte_utils::be64_to_array(htlcs.len() as u64))?;
901 for &ref htlc in htlcs.iter() {
905 self.funding_redeemscript.write(writer)?;
906 self.channel_value_satoshis.write(writer)?;
908 match self.their_cur_revocation_points {
909 Some((idx, pubkey, second_option)) => {
910 writer.write_all(&byte_utils::be48_to_array(idx))?;
911 writer.write_all(&pubkey.serialize())?;
912 match second_option {
913 Some(second_pubkey) => {
914 writer.write_all(&second_pubkey.serialize())?;
917 writer.write_all(&[0; 33])?;
922 writer.write_all(&byte_utils::be48_to_array(0))?;
926 writer.write_all(&byte_utils::be16_to_array(self.our_to_self_delay))?;
927 writer.write_all(&byte_utils::be16_to_array(self.their_to_self_delay))?;
929 self.commitment_secrets.write(writer)?;
931 macro_rules! serialize_htlc_in_commitment {
932 ($htlc_output: expr) => {
933 writer.write_all(&[$htlc_output.offered as u8; 1])?;
934 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
935 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
936 writer.write_all(&$htlc_output.payment_hash.0[..])?;
937 $htlc_output.transaction_output_index.write(writer)?;
941 writer.write_all(&byte_utils::be64_to_array(self.remote_claimable_outpoints.len() as u64))?;
942 for (ref txid, ref htlc_infos) in self.remote_claimable_outpoints.iter() {
943 writer.write_all(&txid[..])?;
944 writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
945 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
946 serialize_htlc_in_commitment!(htlc_output);
947 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
951 writer.write_all(&byte_utils::be64_to_array(self.remote_commitment_txn_on_chain.len() as u64))?;
952 for (ref txid, &(commitment_number, ref txouts)) in self.remote_commitment_txn_on_chain.iter() {
953 writer.write_all(&txid[..])?;
954 writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
955 (txouts.len() as u64).write(writer)?;
956 for script in txouts.iter() {
957 script.write(writer)?;
961 writer.write_all(&byte_utils::be64_to_array(self.remote_hash_commitment_number.len() as u64))?;
962 for (ref payment_hash, commitment_number) in self.remote_hash_commitment_number.iter() {
963 writer.write_all(&payment_hash.0[..])?;
964 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
967 macro_rules! serialize_local_tx {
968 ($local_tx: expr) => {
969 $local_tx.txid.write(writer)?;
970 writer.write_all(&$local_tx.revocation_key.serialize())?;
971 writer.write_all(&$local_tx.a_htlc_key.serialize())?;
972 writer.write_all(&$local_tx.b_htlc_key.serialize())?;
973 writer.write_all(&$local_tx.delayed_payment_key.serialize())?;
974 writer.write_all(&$local_tx.per_commitment_point.serialize())?;
976 writer.write_all(&byte_utils::be64_to_array($local_tx.feerate_per_kw))?;
977 writer.write_all(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64))?;
978 for &(ref htlc_output, ref sig, ref htlc_source) in $local_tx.htlc_outputs.iter() {
979 serialize_htlc_in_commitment!(htlc_output);
980 if let &Some(ref their_sig) = sig {
982 writer.write_all(&their_sig.serialize_compact())?;
986 htlc_source.write(writer)?;
991 if let Some(ref prev_local_tx) = self.prev_local_signed_commitment_tx {
992 writer.write_all(&[1; 1])?;
993 serialize_local_tx!(prev_local_tx);
995 writer.write_all(&[0; 1])?;
998 serialize_local_tx!(self.current_local_commitment_tx);
1000 writer.write_all(&byte_utils::be48_to_array(self.current_remote_commitment_number))?;
1001 writer.write_all(&byte_utils::be48_to_array(self.current_local_commitment_number))?;
1003 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
1004 for payment_preimage in self.payment_preimages.values() {
1005 writer.write_all(&payment_preimage.0[..])?;
1008 writer.write_all(&byte_utils::be64_to_array(self.pending_htlcs_updated.len() as u64))?;
1009 for data in self.pending_htlcs_updated.iter() {
1010 data.write(writer)?;
1013 writer.write_all(&byte_utils::be64_to_array(self.pending_events.len() as u64))?;
1014 for event in self.pending_events.iter() {
1015 event.write(writer)?;
1018 self.last_block_hash.write(writer)?;
1020 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_waiting_threshold_conf.len() as u64))?;
1021 for (ref target, ref events) in self.onchain_events_waiting_threshold_conf.iter() {
1022 writer.write_all(&byte_utils::be32_to_array(**target))?;
1023 writer.write_all(&byte_utils::be64_to_array(events.len() as u64))?;
1024 for ev in events.iter() {
1026 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1028 htlc_update.0.write(writer)?;
1029 htlc_update.1.write(writer)?;
1031 OnchainEvent::MaturingOutput { ref descriptor } => {
1033 descriptor.write(writer)?;
1039 (self.outputs_to_watch.len() as u64).write(writer)?;
1040 for (txid, output_scripts) in self.outputs_to_watch.iter() {
1041 txid.write(writer)?;
1042 (output_scripts.len() as u64).write(writer)?;
1043 for script in output_scripts.iter() {
1044 script.write(writer)?;
1047 self.onchain_tx_handler.write(writer)?;
1049 self.lockdown_from_offchain.write(writer)?;
1050 self.local_tx_signed.write(writer)?;
1056 impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
1057 pub(super) fn new(keys: ChanSigner, shutdown_pubkey: &PublicKey,
1058 our_to_self_delay: u16, destination_script: &Script, funding_info: (OutPoint, Script),
1059 remote_htlc_base_key: &PublicKey, remote_delayed_payment_base_key: &PublicKey,
1060 their_to_self_delay: u16, funding_redeemscript: Script, channel_value_satoshis: u64,
1061 commitment_transaction_number_obscure_factor: u64,
1062 initial_local_commitment_tx: LocalCommitmentTransaction) -> ChannelMonitor<ChanSigner> {
1064 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
1065 let our_channel_close_key_hash = WPubkeyHash::hash(&shutdown_pubkey.serialize());
1066 let shutdown_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
1067 let payment_key_hash = WPubkeyHash::hash(&keys.pubkeys().payment_point.serialize());
1068 let remote_payment_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_key_hash[..]).into_script();
1070 let remote_tx_cache = RemoteTxCache { remote_delayed_payment_base_key: *remote_delayed_payment_base_key, remote_htlc_base_key: *remote_htlc_base_key, per_htlc: HashMap::new() };
1072 let mut onchain_tx_handler = OnchainTxHandler::new(destination_script.clone(), keys.clone(), their_to_self_delay, *remote_delayed_payment_base_key, *remote_htlc_base_key ,our_to_self_delay);
1074 let local_tx_sequence = initial_local_commitment_tx.unsigned_tx.input[0].sequence as u64;
1075 let local_tx_locktime = initial_local_commitment_tx.unsigned_tx.lock_time as u64;
1076 let local_commitment_tx = LocalSignedTx {
1077 txid: initial_local_commitment_tx.txid(),
1078 revocation_key: initial_local_commitment_tx.local_keys.revocation_key,
1079 a_htlc_key: initial_local_commitment_tx.local_keys.a_htlc_key,
1080 b_htlc_key: initial_local_commitment_tx.local_keys.b_htlc_key,
1081 delayed_payment_key: initial_local_commitment_tx.local_keys.a_delayed_payment_key,
1082 per_commitment_point: initial_local_commitment_tx.local_keys.per_commitment_point,
1083 feerate_per_kw: initial_local_commitment_tx.feerate_per_kw,
1084 htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
1086 // Returning a monitor error before updating tracking points means in case of using
1087 // a concurrent watchtower implementation for same channel, if this one doesn't
1088 // reject update as we do, you MAY have the latest local valid commitment tx onchain
1089 // for which you want to spend outputs. We're NOT robust again this scenario right
1090 // now but we should consider it later.
1091 onchain_tx_handler.provide_latest_local_tx(initial_local_commitment_tx).unwrap();
1094 latest_update_id: 0,
1095 commitment_transaction_number_obscure_factor,
1097 destination_script: destination_script.clone(),
1098 broadcasted_local_revokable_script: None,
1099 remote_payment_script,
1104 current_remote_commitment_txid: None,
1105 prev_remote_commitment_txid: None,
1108 funding_redeemscript,
1109 channel_value_satoshis: channel_value_satoshis,
1110 their_cur_revocation_points: None,
1113 their_to_self_delay,
1115 commitment_secrets: CounterpartyCommitmentSecrets::new(),
1116 remote_claimable_outpoints: HashMap::new(),
1117 remote_commitment_txn_on_chain: HashMap::new(),
1118 remote_hash_commitment_number: HashMap::new(),
1120 prev_local_signed_commitment_tx: None,
1121 current_local_commitment_tx: local_commitment_tx,
1122 current_remote_commitment_number: 1 << 48,
1123 current_local_commitment_number: 0xffff_ffff_ffff - ((((local_tx_sequence & 0xffffff) << 3*8) | (local_tx_locktime as u64 & 0xffffff)) ^ commitment_transaction_number_obscure_factor),
1125 payment_preimages: HashMap::new(),
1126 pending_htlcs_updated: Vec::new(),
1127 pending_events: Vec::new(),
1129 onchain_events_waiting_threshold_conf: HashMap::new(),
1130 outputs_to_watch: HashMap::new(),
1134 lockdown_from_offchain: false,
1135 local_tx_signed: false,
1137 last_block_hash: Default::default(),
1138 secp_ctx: Secp256k1::new(),
1142 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
1143 /// needed by local commitment transactions HTCLs nor by remote ones. Unless we haven't already seen remote
1144 /// commitment transaction's secret, they are de facto pruned (we can use revocation key).
1145 pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
1146 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
1147 return Err(MonitorUpdateError("Previous secret did not match new one"));
1150 // Prune HTLCs from the previous remote commitment tx so we don't generate failure/fulfill
1151 // events for now-revoked/fulfilled HTLCs.
1152 if let Some(txid) = self.prev_remote_commitment_txid.take() {
1153 for &mut (_, ref mut source) in self.remote_claimable_outpoints.get_mut(&txid).unwrap() {
1158 if !self.payment_preimages.is_empty() {
1159 let cur_local_signed_commitment_tx = &self.current_local_commitment_tx;
1160 let prev_local_signed_commitment_tx = self.prev_local_signed_commitment_tx.as_ref();
1161 let min_idx = self.get_min_seen_secret();
1162 let remote_hash_commitment_number = &mut self.remote_hash_commitment_number;
1164 self.payment_preimages.retain(|&k, _| {
1165 for &(ref htlc, _, _) in cur_local_signed_commitment_tx.htlc_outputs.iter() {
1166 if k == htlc.payment_hash {
1170 if let Some(prev_local_commitment_tx) = prev_local_signed_commitment_tx {
1171 for &(ref htlc, _, _) in prev_local_commitment_tx.htlc_outputs.iter() {
1172 if k == htlc.payment_hash {
1177 let contains = if let Some(cn) = remote_hash_commitment_number.get(&k) {
1184 remote_hash_commitment_number.remove(&k);
1193 /// Informs this monitor of the latest remote (ie non-broadcastable) commitment transaction.
1194 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
1195 /// possibly future revocation/preimage information) to claim outputs where possible.
1196 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
1197 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 {
1198 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
1199 // so that a remote monitor doesn't learn anything unless there is a malicious close.
1200 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
1202 for &(ref htlc, _) in &htlc_outputs {
1203 self.remote_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
1206 let new_txid = unsigned_commitment_tx.txid();
1207 log_trace!(logger, "Tracking new remote commitment transaction with txid {} at commitment number {} with {} HTLC outputs", new_txid, commitment_number, htlc_outputs.len());
1208 log_trace!(logger, "New potential remote commitment transaction: {}", encode::serialize_hex(unsigned_commitment_tx));
1209 self.prev_remote_commitment_txid = self.current_remote_commitment_txid.take();
1210 self.current_remote_commitment_txid = Some(new_txid);
1211 self.remote_claimable_outpoints.insert(new_txid, htlc_outputs.clone());
1212 self.current_remote_commitment_number = commitment_number;
1213 //TODO: Merge this into the other per-remote-transaction output storage stuff
1214 match self.their_cur_revocation_points {
1215 Some(old_points) => {
1216 if old_points.0 == commitment_number + 1 {
1217 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
1218 } else if old_points.0 == commitment_number + 2 {
1219 if let Some(old_second_point) = old_points.2 {
1220 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
1222 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1225 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1229 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1232 let mut htlcs = Vec::with_capacity(htlc_outputs.len());
1233 for htlc in htlc_outputs {
1234 if htlc.0.transaction_output_index.is_some() {
1238 self.remote_tx_cache.per_htlc.insert(new_txid, htlcs.clone());
1239 self.onchain_tx_handler.provide_latest_remote_tx(new_txid, htlcs);
1242 /// Informs this monitor of the latest local (ie broadcastable) commitment transaction. The
1243 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
1244 /// is important that any clones of this channel monitor (including remote clones) by kept
1245 /// up-to-date as our local commitment transaction is updated.
1246 /// Panics if set_their_to_self_delay has never been called.
1247 pub(super) fn provide_latest_local_commitment_tx_info(&mut self, commitment_tx: LocalCommitmentTransaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), MonitorUpdateError> {
1248 if self.local_tx_signed {
1249 return Err(MonitorUpdateError("A local commitment tx has already been signed, no new local commitment txn can be sent to our counterparty"));
1251 let txid = commitment_tx.txid();
1252 let sequence = commitment_tx.unsigned_tx.input[0].sequence as u64;
1253 let locktime = commitment_tx.unsigned_tx.lock_time as u64;
1254 let mut new_local_commitment_tx = LocalSignedTx {
1256 revocation_key: commitment_tx.local_keys.revocation_key,
1257 a_htlc_key: commitment_tx.local_keys.a_htlc_key,
1258 b_htlc_key: commitment_tx.local_keys.b_htlc_key,
1259 delayed_payment_key: commitment_tx.local_keys.a_delayed_payment_key,
1260 per_commitment_point: commitment_tx.local_keys.per_commitment_point,
1261 feerate_per_kw: commitment_tx.feerate_per_kw,
1262 htlc_outputs: htlc_outputs,
1264 // Returning a monitor error before updating tracking points means in case of using
1265 // a concurrent watchtower implementation for same channel, if this one doesn't
1266 // reject update as we do, you MAY have the latest local valid commitment tx onchain
1267 // for which you want to spend outputs. We're NOT robust again this scenario right
1268 // now but we should consider it later.
1269 if let Err(_) = self.onchain_tx_handler.provide_latest_local_tx(commitment_tx) {
1270 return Err(MonitorUpdateError("Local commitment signed has already been signed, no further update of LOCAL commitment transaction is allowed"));
1272 self.current_local_commitment_number = 0xffff_ffff_ffff - ((((sequence & 0xffffff) << 3*8) | (locktime as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
1273 mem::swap(&mut new_local_commitment_tx, &mut self.current_local_commitment_tx);
1274 self.prev_local_signed_commitment_tx = Some(new_local_commitment_tx);
1278 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
1279 /// commitment_tx_infos which contain the payment hash have been revoked.
1280 pub(super) fn provide_payment_preimage(&mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage) {
1281 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
1284 pub(super) fn broadcast_latest_local_commitment_txn<B: Deref, L: Deref>(&mut self, broadcaster: &B, logger: &L)
1285 where B::Target: BroadcasterInterface,
1288 for tx in self.get_latest_local_commitment_txn(logger).iter() {
1289 broadcaster.broadcast_transaction(tx);
1293 /// Used in Channel to cheat wrt the update_ids since it plays games, will be removed soon!
1294 pub(super) fn update_monitor_ooo<L: Deref>(&mut self, mut updates: ChannelMonitorUpdate, logger: &L) -> Result<(), MonitorUpdateError> where L::Target: Logger {
1295 for update in updates.updates.drain(..) {
1297 ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { commitment_tx, htlc_outputs } => {
1298 if self.lockdown_from_offchain { panic!(); }
1299 self.provide_latest_local_commitment_tx_info(commitment_tx, htlc_outputs)?
1301 ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
1302 self.provide_latest_remote_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point, logger),
1303 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
1304 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
1305 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
1306 self.provide_secret(idx, secret)?,
1307 ChannelMonitorUpdateStep::ChannelForceClosed { .. } => {},
1310 self.latest_update_id = updates.update_id;
1314 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
1317 /// panics if the given update is not the next update by update_id.
1318 pub fn update_monitor<B: Deref, L: Deref>(&mut self, mut updates: ChannelMonitorUpdate, broadcaster: &B, logger: &L) -> Result<(), MonitorUpdateError>
1319 where B::Target: BroadcasterInterface,
1322 if self.latest_update_id + 1 != updates.update_id {
1323 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
1325 for update in updates.updates.drain(..) {
1327 ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { commitment_tx, htlc_outputs } => {
1328 if self.lockdown_from_offchain { panic!(); }
1329 self.provide_latest_local_commitment_tx_info(commitment_tx, htlc_outputs)?
1331 ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
1332 self.provide_latest_remote_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point, logger),
1333 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
1334 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
1335 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
1336 self.provide_secret(idx, secret)?,
1337 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
1338 self.lockdown_from_offchain = true;
1339 if should_broadcast {
1340 self.broadcast_latest_local_commitment_txn(broadcaster, logger);
1342 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");
1347 self.latest_update_id = updates.update_id;
1351 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
1353 pub fn get_latest_update_id(&self) -> u64 {
1354 self.latest_update_id
1357 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
1358 pub fn get_funding_txo(&self) -> OutPoint {
1362 /// Gets a list of txids, with their output scripts (in the order they appear in the
1363 /// transaction), which we must learn about spends of via block_connected().
1364 pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<Script>> {
1365 &self.outputs_to_watch
1368 /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
1369 /// Generally useful when deserializing as during normal operation the return values of
1370 /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
1371 /// that the get_funding_txo outpoint and transaction must also be monitored for!).
1372 pub fn get_monitored_outpoints(&self) -> Vec<(Txid, u32, &Script)> {
1373 let mut res = Vec::with_capacity(self.remote_commitment_txn_on_chain.len() * 2);
1374 for (ref txid, &(_, ref outputs)) in self.remote_commitment_txn_on_chain.iter() {
1375 for (idx, output) in outputs.iter().enumerate() {
1376 res.push(((*txid).clone(), idx as u32, output));
1382 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1383 /// ChannelManager via ManyChannelMonitor::get_and_clear_pending_htlcs_updated().
1384 pub fn get_and_clear_pending_htlcs_updated(&mut self) -> Vec<HTLCUpdate> {
1385 let mut ret = Vec::new();
1386 mem::swap(&mut ret, &mut self.pending_htlcs_updated);
1390 /// Gets the list of pending events which were generated by previous actions, clearing the list
1393 /// This is called by ManyChannelMonitor::get_and_clear_pending_events() and is equivalent to
1394 /// EventsProvider::get_and_clear_pending_events() except that it requires &mut self as we do
1395 /// no internal locking in ChannelMonitors.
1396 pub fn get_and_clear_pending_events(&mut self) -> Vec<events::Event> {
1397 let mut ret = Vec::new();
1398 mem::swap(&mut ret, &mut self.pending_events);
1402 /// Can only fail if idx is < get_min_seen_secret
1403 pub(super) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
1404 self.commitment_secrets.get_secret(idx)
1407 pub(super) fn get_min_seen_secret(&self) -> u64 {
1408 self.commitment_secrets.get_min_seen_secret()
1411 pub(super) fn get_cur_remote_commitment_number(&self) -> u64 {
1412 self.current_remote_commitment_number
1415 pub(super) fn get_cur_local_commitment_number(&self) -> u64 {
1416 self.current_local_commitment_number
1419 /// Attempts to claim a remote commitment transaction's outputs using the revocation key and
1420 /// data in remote_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
1421 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
1422 /// HTLC-Success/HTLC-Timeout transactions.
1423 /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
1424 /// revoked remote commitment tx
1425 fn check_spend_remote_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) where L::Target: Logger {
1426 // Most secp and related errors trying to create keys means we have no hope of constructing
1427 // a spend transaction...so we return no transactions to broadcast
1428 let mut claimable_outpoints = Vec::new();
1429 let mut watch_outputs = Vec::new();
1431 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1432 let per_commitment_option = self.remote_claimable_outpoints.get(&commitment_txid);
1434 macro_rules! ignore_error {
1435 ( $thing : expr ) => {
1438 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs))
1443 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);
1444 if commitment_number >= self.get_min_seen_secret() {
1445 let secret = self.get_secret(commitment_number).unwrap();
1446 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1447 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1448 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.keys.pubkeys().revocation_basepoint));
1449 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));
1451 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.our_to_self_delay, &delayed_key);
1452 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1454 // First, process non-htlc outputs (to_local & to_remote)
1455 for (idx, outp) in tx.output.iter().enumerate() {
1456 if outp.script_pubkey == revokeable_p2wsh {
1457 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 };
1458 claimable_outpoints.push(ClaimRequest { absolute_timelock: height + self.our_to_self_delay as u32, aggregable: true, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: idx as u32 }, witness_data});
1462 // Then, try to find revoked htlc outputs
1463 if let Some(ref per_commitment_data) = per_commitment_option {
1464 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1465 if let Some(transaction_output_index) = htlc.transaction_output_index {
1466 if transaction_output_index as usize >= tx.output.len() ||
1467 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1468 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1470 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()) };
1471 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable: true, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1476 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
1477 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
1478 // We're definitely a remote commitment transaction!
1479 log_trace!(logger, "Got broadcast of revoked remote commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
1480 watch_outputs.append(&mut tx.output.clone());
1481 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1483 macro_rules! check_htlc_fails {
1484 ($txid: expr, $commitment_tx: expr) => {
1485 if let Some(ref outpoints) = self.remote_claimable_outpoints.get($txid) {
1486 for &(ref htlc, ref source_option) in outpoints.iter() {
1487 if let &Some(ref source) = source_option {
1488 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), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1489 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1490 hash_map::Entry::Occupied(mut entry) => {
1491 let e = entry.get_mut();
1492 e.retain(|ref event| {
1494 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1495 return htlc_update.0 != **source
1500 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1502 hash_map::Entry::Vacant(entry) => {
1503 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1511 if let Some(ref txid) = self.current_remote_commitment_txid {
1512 check_htlc_fails!(txid, "current");
1514 if let Some(ref txid) = self.prev_remote_commitment_txid {
1515 check_htlc_fails!(txid, "remote");
1517 // No need to check local commitment txn, symmetric HTLCSource must be present as per-htlc data on remote commitment tx
1519 } else if let Some(per_commitment_data) = per_commitment_option {
1520 // While this isn't useful yet, there is a potential race where if a counterparty
1521 // revokes a state at the same time as the commitment transaction for that state is
1522 // confirmed, and the watchtower receives the block before the user, the user could
1523 // upload a new ChannelMonitor with the revocation secret but the watchtower has
1524 // already processed the block, resulting in the remote_commitment_txn_on_chain entry
1525 // not being generated by the above conditional. Thus, to be safe, we go ahead and
1527 watch_outputs.append(&mut tx.output.clone());
1528 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1530 log_trace!(logger, "Got broadcast of non-revoked remote commitment transaction {}", commitment_txid);
1532 macro_rules! check_htlc_fails {
1533 ($txid: expr, $commitment_tx: expr, $id: tt) => {
1534 if let Some(ref latest_outpoints) = self.remote_claimable_outpoints.get($txid) {
1535 $id: for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1536 if let &Some(ref source) = source_option {
1537 // Check if the HTLC is present in the commitment transaction that was
1538 // broadcast, but not if it was below the dust limit, which we should
1539 // fail backwards immediately as there is no way for us to learn the
1540 // payment_preimage.
1541 // Note that if the dust limit were allowed to change between
1542 // commitment transactions we'd want to be check whether *any*
1543 // broadcastable commitment transaction has the HTLC in it, but it
1544 // cannot currently change after channel initialization, so we don't
1546 for &(ref broadcast_htlc, ref broadcast_source) in per_commitment_data.iter() {
1547 if broadcast_htlc.transaction_output_index.is_some() && Some(source) == broadcast_source.as_ref() {
1551 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);
1552 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1553 hash_map::Entry::Occupied(mut entry) => {
1554 let e = entry.get_mut();
1555 e.retain(|ref event| {
1557 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1558 return htlc_update.0 != **source
1563 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1565 hash_map::Entry::Vacant(entry) => {
1566 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1574 if let Some(ref txid) = self.current_remote_commitment_txid {
1575 check_htlc_fails!(txid, "current", 'current_loop);
1577 if let Some(ref txid) = self.prev_remote_commitment_txid {
1578 check_htlc_fails!(txid, "previous", 'prev_loop);
1581 if let Some(revocation_points) = self.their_cur_revocation_points {
1582 let revocation_point_option =
1583 if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1584 else if let Some(point) = revocation_points.2.as_ref() {
1585 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1587 if let Some(revocation_point) = revocation_point_option {
1588 self.remote_payment_script = {
1589 // Note that the Network here is ignored as we immediately drop the address for the
1590 // script_pubkey version
1591 let payment_hash160 = WPubkeyHash::hash(&PublicKey::from_secret_key(&self.secp_ctx, &self.keys.payment_key()).serialize());
1592 Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_hash160[..]).into_script()
1595 // Then, try to find htlc outputs
1596 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1597 if let Some(transaction_output_index) = htlc.transaction_output_index {
1598 if transaction_output_index as usize >= tx.output.len() ||
1599 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1600 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1602 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
1603 let aggregable = if !htlc.offered { false } else { true };
1604 if preimage.is_some() || !htlc.offered {
1605 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() };
1606 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1613 (claimable_outpoints, (commitment_txid, watch_outputs))
1616 /// Attempts to claim a remote HTLC-Success/HTLC-Timeout's outputs using the revocation key
1617 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 {
1618 let htlc_txid = tx.txid();
1619 if tx.input.len() != 1 || tx.output.len() != 1 || tx.input[0].witness.len() != 5 {
1620 return (Vec::new(), None)
1623 macro_rules! ignore_error {
1624 ( $thing : expr ) => {
1627 Err(_) => return (Vec::new(), None)
1632 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
1633 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1634 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1636 log_trace!(logger, "Remote HTLC broadcast {}:{}", htlc_txid, 0);
1637 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 };
1638 let claimable_outpoints = vec!(ClaimRequest { absolute_timelock: height + self.our_to_self_delay as u32, aggregable: true, outpoint: BitcoinOutPoint { txid: htlc_txid, vout: 0}, witness_data });
1639 (claimable_outpoints, Some((htlc_txid, tx.output.clone())))
1642 fn broadcast_by_local_state(&self, commitment_tx: &Transaction, local_tx: &LocalSignedTx) -> (Vec<ClaimRequest>, Vec<TxOut>, Option<(Script, PublicKey, PublicKey)>) {
1643 let mut claim_requests = Vec::with_capacity(local_tx.htlc_outputs.len());
1644 let mut watch_outputs = Vec::with_capacity(local_tx.htlc_outputs.len());
1646 let redeemscript = chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.their_to_self_delay, &local_tx.delayed_payment_key);
1647 let broadcasted_local_revokable_script = Some((redeemscript.to_v0_p2wsh(), local_tx.per_commitment_point.clone(), local_tx.revocation_key.clone()));
1649 for &(ref htlc, _, _) in local_tx.htlc_outputs.iter() {
1650 if let Some(transaction_output_index) = htlc.transaction_output_index {
1651 claim_requests.push(ClaimRequest { absolute_timelock: ::std::u32::MAX, aggregable: false, outpoint: BitcoinOutPoint { txid: local_tx.txid, vout: transaction_output_index as u32 },
1652 witness_data: InputMaterial::LocalHTLC {
1653 preimage: if !htlc.offered {
1654 if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1655 Some(preimage.clone())
1657 // We can't build an HTLC-Success transaction without the preimage
1661 amount: htlc.amount_msat,
1663 watch_outputs.push(commitment_tx.output[transaction_output_index as usize].clone());
1667 (claim_requests, watch_outputs, broadcasted_local_revokable_script)
1670 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1671 /// revoked using data in local_claimable_outpoints.
1672 /// Should not be used if check_spend_revoked_transaction succeeds.
1673 fn check_spend_local_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) where L::Target: Logger {
1674 let commitment_txid = tx.txid();
1675 let mut claim_requests = Vec::new();
1676 let mut watch_outputs = Vec::new();
1678 macro_rules! wait_threshold_conf {
1679 ($height: expr, $source: expr, $commitment_tx: expr, $payment_hash: expr) => {
1680 log_trace!(logger, "Failing HTLC with payment_hash {} from {} local commitment tx due to broadcast of transaction, waiting confirmation (at height{})", log_bytes!($payment_hash.0), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1681 match self.onchain_events_waiting_threshold_conf.entry($height + ANTI_REORG_DELAY - 1) {
1682 hash_map::Entry::Occupied(mut entry) => {
1683 let e = entry.get_mut();
1684 e.retain(|ref event| {
1686 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1687 return htlc_update.0 != $source
1692 e.push(OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)});
1694 hash_map::Entry::Vacant(entry) => {
1695 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)}]);
1701 macro_rules! append_onchain_update {
1702 ($updates: expr) => {
1703 claim_requests = $updates.0;
1704 watch_outputs.append(&mut $updates.1);
1705 self.broadcasted_local_revokable_script = $updates.2;
1709 // HTLCs set may differ between last and previous local commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
1710 let mut is_local_tx = false;
1712 if self.current_local_commitment_tx.txid == commitment_txid {
1714 log_trace!(logger, "Got latest local commitment tx broadcast, searching for available HTLCs to claim");
1715 let mut res = self.broadcast_by_local_state(tx, &self.current_local_commitment_tx);
1716 append_onchain_update!(res);
1717 } else if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1718 if local_tx.txid == commitment_txid {
1720 log_trace!(logger, "Got previous local commitment tx broadcast, searching for available HTLCs to claim");
1721 let mut res = self.broadcast_by_local_state(tx, local_tx);
1722 append_onchain_update!(res);
1726 macro_rules! fail_dust_htlcs_after_threshold_conf {
1727 ($local_tx: expr) => {
1728 for &(ref htlc, _, ref source) in &$local_tx.htlc_outputs {
1729 if htlc.transaction_output_index.is_none() {
1730 if let &Some(ref source) = source {
1731 wait_threshold_conf!(height, source.clone(), "lastest", htlc.payment_hash.clone());
1739 fail_dust_htlcs_after_threshold_conf!(self.current_local_commitment_tx);
1740 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1741 fail_dust_htlcs_after_threshold_conf!(local_tx);
1745 (claim_requests, (commitment_txid, watch_outputs))
1748 /// Used by ChannelManager deserialization to broadcast the latest local state if its copy of
1749 /// the Channel was out-of-date. You may use it to get a broadcastable local toxic tx in case of
1750 /// fallen-behind, i.e when receiving a channel_reestablish with a proof that our remote side knows
1751 /// a higher revocation secret than the local commitment number we are aware of. Broadcasting these
1752 /// transactions are UNSAFE, as they allow remote side to punish you. Nevertheless you may want to
1753 /// broadcast them if remote don't close channel with his higher commitment transaction after a
1754 /// substantial amount of time (a month or even a year) to get back funds. Best may be to contact
1755 /// out-of-band the other node operator to coordinate with him if option is available to you.
1756 /// In any-case, choice is up to the user.
1757 pub fn get_latest_local_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1758 log_trace!(logger, "Getting signed latest local commitment transaction!");
1759 self.local_tx_signed = true;
1760 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_local_tx(&self.funding_redeemscript) {
1761 let txid = commitment_tx.txid();
1762 let mut res = vec![commitment_tx];
1763 for htlc in self.current_local_commitment_tx.htlc_outputs.iter() {
1764 if let Some(vout) = htlc.0.transaction_output_index {
1765 let preimage = if !htlc.0.offered {
1766 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1767 // We can't build an HTLC-Success transaction without the preimage
1771 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
1772 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1777 // 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.
1778 // The data will be re-generated and tracked in check_spend_local_transaction if we get a confirmation.
1784 /// Unsafe test-only version of get_latest_local_commitment_txn used by our test framework
1785 /// to bypass LocalCommitmentTransaction state update lockdown after signature and generate
1786 /// revoked commitment transaction.
1788 pub fn unsafe_get_latest_local_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1789 log_trace!(logger, "Getting signed copy of latest local commitment transaction!");
1790 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_copy_local_tx(&self.funding_redeemscript) {
1791 let txid = commitment_tx.txid();
1792 let mut res = vec![commitment_tx];
1793 for htlc in self.current_local_commitment_tx.htlc_outputs.iter() {
1794 if let Some(vout) = htlc.0.transaction_output_index {
1795 let preimage = if !htlc.0.offered {
1796 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1797 // We can't build an HTLC-Success transaction without the preimage
1801 if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
1802 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1812 /// Called by SimpleManyChannelMonitor::block_connected, which implements
1813 /// ChainListener::block_connected.
1814 /// Eventually this should be pub and, roughly, implement ChainListener, however this requires
1815 /// &mut self, as well as returns new spendable outputs and outpoints to watch for spending of
1817 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>)>
1818 where B::Target: BroadcasterInterface,
1819 F::Target: FeeEstimator,
1822 for tx in txn_matched {
1823 let mut output_val = 0;
1824 for out in tx.output.iter() {
1825 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1826 output_val += out.value;
1827 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1831 log_trace!(logger, "Block {} at height {} connected with {} txn matched", block_hash, height, txn_matched.len());
1832 let mut watch_outputs = Vec::new();
1833 let mut claimable_outpoints = Vec::new();
1834 for tx in txn_matched {
1835 if tx.input.len() == 1 {
1836 // Assuming our keys were not leaked (in which case we're screwed no matter what),
1837 // commitment transactions and HTLC transactions will all only ever have one input,
1838 // which is an easy way to filter out any potential non-matching txn for lazy
1840 let prevout = &tx.input[0].previous_output;
1841 if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
1842 if (tx.input[0].sequence >> 8*3) as u8 == 0x80 && (tx.lock_time >> 8*3) as u8 == 0x20 {
1843 let (mut new_outpoints, new_outputs) = self.check_spend_remote_transaction(&tx, height, &logger);
1844 if !new_outputs.1.is_empty() {
1845 watch_outputs.push(new_outputs);
1847 if new_outpoints.is_empty() {
1848 let (mut new_outpoints, new_outputs) = self.check_spend_local_transaction(&tx, height, &logger);
1849 if !new_outputs.1.is_empty() {
1850 watch_outputs.push(new_outputs);
1852 claimable_outpoints.append(&mut new_outpoints);
1854 claimable_outpoints.append(&mut new_outpoints);
1857 if let Some(&(commitment_number, _)) = self.remote_commitment_txn_on_chain.get(&prevout.txid) {
1858 let (mut new_outpoints, new_outputs_option) = self.check_spend_remote_htlc(&tx, commitment_number, height, &logger);
1859 claimable_outpoints.append(&mut new_outpoints);
1860 if let Some(new_outputs) = new_outputs_option {
1861 watch_outputs.push(new_outputs);
1866 // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
1867 // can also be resolved in a few other ways which can have more than one output. Thus,
1868 // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
1869 self.is_resolving_htlc_output(&tx, height, &logger);
1871 self.is_paying_spendable_output(&tx, height, &logger);
1873 let should_broadcast = self.would_broadcast_at_height(height, &logger);
1874 if should_broadcast {
1875 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() }});
1877 if should_broadcast {
1878 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_local_tx(&self.funding_redeemscript) {
1879 let (mut new_outpoints, new_outputs, _) = self.broadcast_by_local_state(&commitment_tx, &self.current_local_commitment_tx);
1880 if !new_outputs.is_empty() {
1881 watch_outputs.push((self.current_local_commitment_tx.txid.clone(), new_outputs));
1883 claimable_outpoints.append(&mut new_outpoints);
1886 if let Some(events) = self.onchain_events_waiting_threshold_conf.remove(&height) {
1889 OnchainEvent::HTLCUpdate { htlc_update } => {
1890 log_trace!(logger, "HTLC {} failure update has got enough confirmations to be passed upstream", log_bytes!((htlc_update.1).0));
1891 self.pending_htlcs_updated.push(HTLCUpdate {
1892 payment_hash: htlc_update.1,
1893 payment_preimage: None,
1894 source: htlc_update.0,
1897 OnchainEvent::MaturingOutput { descriptor } => {
1898 log_trace!(logger, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
1899 self.pending_events.push(events::Event::SpendableOutputs {
1900 outputs: vec![descriptor]
1906 self.onchain_tx_handler.block_connected(txn_matched, claimable_outpoints, height, &*broadcaster, &*fee_estimator, &*logger);
1908 self.last_block_hash = block_hash.clone();
1909 for &(ref txid, ref output_scripts) in watch_outputs.iter() {
1910 self.outputs_to_watch.insert(txid.clone(), output_scripts.iter().map(|o| o.script_pubkey.clone()).collect());
1916 fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, height: u32, block_hash: &BlockHash, broadcaster: B, fee_estimator: F, logger: L)
1917 where B::Target: BroadcasterInterface,
1918 F::Target: FeeEstimator,
1921 log_trace!(logger, "Block {} at height {} disconnected", block_hash, height);
1922 if let Some(_) = self.onchain_events_waiting_threshold_conf.remove(&(height + ANTI_REORG_DELAY - 1)) {
1924 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
1925 //- maturing spendable output has transaction paying us has been disconnected
1928 self.onchain_tx_handler.block_disconnected(height, broadcaster, fee_estimator, logger);
1930 self.last_block_hash = block_hash.clone();
1933 pub(super) fn would_broadcast_at_height<L: Deref>(&self, height: u32, logger: &L) -> bool where L::Target: Logger {
1934 // We need to consider all HTLCs which are:
1935 // * in any unrevoked remote commitment transaction, as they could broadcast said
1936 // transactions and we'd end up in a race, or
1937 // * are in our latest local commitment transaction, as this is the thing we will
1938 // broadcast if we go on-chain.
1939 // Note that we consider HTLCs which were below dust threshold here - while they don't
1940 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
1941 // to the source, and if we don't fail the channel we will have to ensure that the next
1942 // updates that peer sends us are update_fails, failing the channel if not. It's probably
1943 // easier to just fail the channel as this case should be rare enough anyway.
1944 macro_rules! scan_commitment {
1945 ($htlcs: expr, $local_tx: expr) => {
1946 for ref htlc in $htlcs {
1947 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
1948 // chain with enough room to claim the HTLC without our counterparty being able to
1949 // time out the HTLC first.
1950 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
1951 // concern is being able to claim the corresponding inbound HTLC (on another
1952 // channel) before it expires. In fact, we don't even really care if our
1953 // counterparty here claims such an outbound HTLC after it expired as long as we
1954 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
1955 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
1956 // we give ourselves a few blocks of headroom after expiration before going
1957 // on-chain for an expired HTLC.
1958 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
1959 // from us until we've reached the point where we go on-chain with the
1960 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
1961 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
1962 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
1963 // inbound_cltv == height + CLTV_CLAIM_BUFFER
1964 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
1965 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
1966 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
1967 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
1968 // The final, above, condition is checked for statically in channelmanager
1969 // with CHECK_CLTV_EXPIRY_SANITY_2.
1970 let htlc_outbound = $local_tx == htlc.offered;
1971 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
1972 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
1973 log_info!(logger, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
1980 scan_commitment!(self.current_local_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
1982 if let Some(ref txid) = self.current_remote_commitment_txid {
1983 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(txid) {
1984 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
1987 if let Some(ref txid) = self.prev_remote_commitment_txid {
1988 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(txid) {
1989 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
1996 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a local
1997 /// or remote commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
1998 fn is_resolving_htlc_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
1999 'outer_loop: for input in &tx.input {
2000 let mut payment_data = None;
2001 let revocation_sig_claim = (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && input.witness[1].len() == 33)
2002 || (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && input.witness[1].len() == 33);
2003 let accepted_preimage_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::AcceptedHTLC);
2004 let offered_preimage_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC);
2006 macro_rules! log_claim {
2007 ($tx_info: expr, $local_tx: expr, $htlc: expr, $source_avail: expr) => {
2008 // We found the output in question, but aren't failing it backwards
2009 // as we have no corresponding source and no valid remote commitment txid
2010 // to try a weak source binding with same-hash, same-value still-valid offered HTLC.
2011 // This implies either it is an inbound HTLC or an outbound HTLC on a revoked transaction.
2012 let outbound_htlc = $local_tx == $htlc.offered;
2013 if ($local_tx && revocation_sig_claim) ||
2014 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
2015 log_error!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
2016 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2017 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2018 if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back" });
2020 log_info!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
2021 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2022 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2023 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
2028 macro_rules! check_htlc_valid_remote {
2029 ($remote_txid: expr, $htlc_output: expr) => {
2030 if let Some(txid) = $remote_txid {
2031 for &(ref pending_htlc, ref pending_source) in self.remote_claimable_outpoints.get(&txid).unwrap() {
2032 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
2033 if let &Some(ref source) = pending_source {
2034 log_claim!("revoked remote commitment tx", false, pending_htlc, true);
2035 payment_data = Some(((**source).clone(), $htlc_output.payment_hash));
2044 macro_rules! scan_commitment {
2045 ($htlcs: expr, $tx_info: expr, $local_tx: expr) => {
2046 for (ref htlc_output, source_option) in $htlcs {
2047 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
2048 if let Some(ref source) = source_option {
2049 log_claim!($tx_info, $local_tx, htlc_output, true);
2050 // We have a resolution of an HTLC either from one of our latest
2051 // local commitment transactions or an unrevoked remote commitment
2052 // transaction. This implies we either learned a preimage, the HTLC
2053 // has timed out, or we screwed up. In any case, we should now
2054 // resolve the source HTLC with the original sender.
2055 payment_data = Some(((*source).clone(), htlc_output.payment_hash));
2056 } else if !$local_tx {
2057 check_htlc_valid_remote!(self.current_remote_commitment_txid, htlc_output);
2058 if payment_data.is_none() {
2059 check_htlc_valid_remote!(self.prev_remote_commitment_txid, htlc_output);
2062 if payment_data.is_none() {
2063 log_claim!($tx_info, $local_tx, htlc_output, false);
2064 continue 'outer_loop;
2071 if input.previous_output.txid == self.current_local_commitment_tx.txid {
2072 scan_commitment!(self.current_local_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2073 "our latest local commitment tx", true);
2075 if let Some(ref prev_local_signed_commitment_tx) = self.prev_local_signed_commitment_tx {
2076 if input.previous_output.txid == prev_local_signed_commitment_tx.txid {
2077 scan_commitment!(prev_local_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2078 "our previous local commitment tx", true);
2081 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(&input.previous_output.txid) {
2082 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
2083 "remote commitment tx", false);
2086 // Check that scan_commitment, above, decided there is some source worth relaying an
2087 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
2088 if let Some((source, payment_hash)) = payment_data {
2089 let mut payment_preimage = PaymentPreimage([0; 32]);
2090 if accepted_preimage_claim {
2091 if !self.pending_htlcs_updated.iter().any(|update| update.source == source) {
2092 payment_preimage.0.copy_from_slice(&input.witness[3]);
2093 self.pending_htlcs_updated.push(HTLCUpdate {
2095 payment_preimage: Some(payment_preimage),
2099 } else if offered_preimage_claim {
2100 if !self.pending_htlcs_updated.iter().any(|update| update.source == source) {
2101 payment_preimage.0.copy_from_slice(&input.witness[1]);
2102 self.pending_htlcs_updated.push(HTLCUpdate {
2104 payment_preimage: Some(payment_preimage),
2109 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);
2110 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2111 hash_map::Entry::Occupied(mut entry) => {
2112 let e = entry.get_mut();
2113 e.retain(|ref event| {
2115 OnchainEvent::HTLCUpdate { ref htlc_update } => {
2116 return htlc_update.0 != source
2121 e.push(OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)});
2123 hash_map::Entry::Vacant(entry) => {
2124 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)}]);
2132 /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
2133 fn is_paying_spendable_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2134 let mut spendable_output = None;
2135 for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
2136 if outp.script_pubkey == self.destination_script {
2137 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2138 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2139 output: outp.clone(),
2142 } else if let Some(ref broadcasted_local_revokable_script) = self.broadcasted_local_revokable_script {
2143 if broadcasted_local_revokable_script.0 == outp.script_pubkey {
2144 spendable_output = Some(SpendableOutputDescriptor::DynamicOutputP2WSH {
2145 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2146 per_commitment_point: broadcasted_local_revokable_script.1,
2147 to_self_delay: self.their_to_self_delay,
2148 output: outp.clone(),
2149 key_derivation_params: self.keys.key_derivation_params(),
2150 remote_revocation_pubkey: broadcasted_local_revokable_script.2.clone(),
2154 } else if self.remote_payment_script == outp.script_pubkey {
2155 spendable_output = Some(SpendableOutputDescriptor::DynamicOutputP2WPKH {
2156 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2157 output: outp.clone(),
2158 key_derivation_params: self.keys.key_derivation_params(),
2161 } else if outp.script_pubkey == self.shutdown_script {
2162 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2163 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2164 output: outp.clone(),
2168 if let Some(spendable_output) = spendable_output {
2169 log_trace!(logger, "Maturing {} until {}", log_spendable!(spendable_output), height + ANTI_REORG_DELAY - 1);
2170 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2171 hash_map::Entry::Occupied(mut entry) => {
2172 let e = entry.get_mut();
2173 e.push(OnchainEvent::MaturingOutput { descriptor: spendable_output });
2175 hash_map::Entry::Vacant(entry) => {
2176 entry.insert(vec![OnchainEvent::MaturingOutput { descriptor: spendable_output }]);
2183 const MAX_ALLOC_SIZE: usize = 64*1024;
2185 impl<ChanSigner: ChannelKeys + Readable> Readable for (BlockHash, ChannelMonitor<ChanSigner>) {
2186 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
2187 macro_rules! unwrap_obj {
2191 Err(_) => return Err(DecodeError::InvalidValue),
2196 let _ver: u8 = Readable::read(reader)?;
2197 let min_ver: u8 = Readable::read(reader)?;
2198 if min_ver > SERIALIZATION_VERSION {
2199 return Err(DecodeError::UnknownVersion);
2202 let latest_update_id: u64 = Readable::read(reader)?;
2203 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
2205 let destination_script = Readable::read(reader)?;
2206 let broadcasted_local_revokable_script = match <u8 as Readable>::read(reader)? {
2208 let revokable_address = Readable::read(reader)?;
2209 let per_commitment_point = Readable::read(reader)?;
2210 let revokable_script = Readable::read(reader)?;
2211 Some((revokable_address, per_commitment_point, revokable_script))
2214 _ => return Err(DecodeError::InvalidValue),
2216 let remote_payment_script = Readable::read(reader)?;
2217 let shutdown_script = Readable::read(reader)?;
2219 let keys = Readable::read(reader)?;
2220 // Technically this can fail and serialize fail a round-trip, but only for serialization of
2221 // barely-init'd ChannelMonitors that we can't do anything with.
2222 let outpoint = OutPoint {
2223 txid: Readable::read(reader)?,
2224 index: Readable::read(reader)?,
2226 let funding_info = (outpoint, Readable::read(reader)?);
2227 let current_remote_commitment_txid = Readable::read(reader)?;
2228 let prev_remote_commitment_txid = Readable::read(reader)?;
2230 let remote_tx_cache = {
2231 let remote_delayed_payment_base_key = Readable::read(reader)?;
2232 let remote_htlc_base_key = Readable::read(reader)?;
2233 let per_htlc_len: u64 = Readable::read(reader)?;
2234 let mut per_htlc = HashMap::with_capacity(cmp::min(per_htlc_len as usize, MAX_ALLOC_SIZE / 64));
2235 for _ in 0..per_htlc_len {
2236 let txid: Txid = Readable::read(reader)?;
2237 let htlcs_count: u64 = Readable::read(reader)?;
2238 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
2239 for _ in 0..htlcs_count {
2240 let htlc = Readable::read(reader)?;
2243 if let Some(_) = per_htlc.insert(txid, htlcs) {
2244 return Err(DecodeError::InvalidValue);
2248 remote_delayed_payment_base_key,
2249 remote_htlc_base_key,
2253 let funding_redeemscript = Readable::read(reader)?;
2254 let channel_value_satoshis = Readable::read(reader)?;
2256 let their_cur_revocation_points = {
2257 let first_idx = <U48 as Readable>::read(reader)?.0;
2261 let first_point = Readable::read(reader)?;
2262 let second_point_slice: [u8; 33] = Readable::read(reader)?;
2263 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
2264 Some((first_idx, first_point, None))
2266 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
2271 let our_to_self_delay: u16 = Readable::read(reader)?;
2272 let their_to_self_delay: u16 = Readable::read(reader)?;
2274 let commitment_secrets = Readable::read(reader)?;
2276 macro_rules! read_htlc_in_commitment {
2279 let offered: bool = Readable::read(reader)?;
2280 let amount_msat: u64 = Readable::read(reader)?;
2281 let cltv_expiry: u32 = Readable::read(reader)?;
2282 let payment_hash: PaymentHash = Readable::read(reader)?;
2283 let transaction_output_index: Option<u32> = Readable::read(reader)?;
2285 HTLCOutputInCommitment {
2286 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
2292 let remote_claimable_outpoints_len: u64 = Readable::read(reader)?;
2293 let mut remote_claimable_outpoints = HashMap::with_capacity(cmp::min(remote_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
2294 for _ in 0..remote_claimable_outpoints_len {
2295 let txid: Txid = Readable::read(reader)?;
2296 let htlcs_count: u64 = Readable::read(reader)?;
2297 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
2298 for _ in 0..htlcs_count {
2299 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
2301 if let Some(_) = remote_claimable_outpoints.insert(txid, htlcs) {
2302 return Err(DecodeError::InvalidValue);
2306 let remote_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
2307 let mut remote_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(remote_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
2308 for _ in 0..remote_commitment_txn_on_chain_len {
2309 let txid: Txid = Readable::read(reader)?;
2310 let commitment_number = <U48 as Readable>::read(reader)?.0;
2311 let outputs_count = <u64 as Readable>::read(reader)?;
2312 let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 8));
2313 for _ in 0..outputs_count {
2314 outputs.push(Readable::read(reader)?);
2316 if let Some(_) = remote_commitment_txn_on_chain.insert(txid, (commitment_number, outputs)) {
2317 return Err(DecodeError::InvalidValue);
2321 let remote_hash_commitment_number_len: u64 = Readable::read(reader)?;
2322 let mut remote_hash_commitment_number = HashMap::with_capacity(cmp::min(remote_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
2323 for _ in 0..remote_hash_commitment_number_len {
2324 let payment_hash: PaymentHash = Readable::read(reader)?;
2325 let commitment_number = <U48 as Readable>::read(reader)?.0;
2326 if let Some(_) = remote_hash_commitment_number.insert(payment_hash, commitment_number) {
2327 return Err(DecodeError::InvalidValue);
2331 macro_rules! read_local_tx {
2334 let txid = Readable::read(reader)?;
2335 let revocation_key = Readable::read(reader)?;
2336 let a_htlc_key = Readable::read(reader)?;
2337 let b_htlc_key = Readable::read(reader)?;
2338 let delayed_payment_key = Readable::read(reader)?;
2339 let per_commitment_point = Readable::read(reader)?;
2340 let feerate_per_kw: u64 = Readable::read(reader)?;
2342 let htlcs_len: u64 = Readable::read(reader)?;
2343 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_len as usize, MAX_ALLOC_SIZE / 128));
2344 for _ in 0..htlcs_len {
2345 let htlc = read_htlc_in_commitment!();
2346 let sigs = match <u8 as Readable>::read(reader)? {
2348 1 => Some(Readable::read(reader)?),
2349 _ => return Err(DecodeError::InvalidValue),
2351 htlcs.push((htlc, sigs, Readable::read(reader)?));
2356 revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, per_commitment_point, feerate_per_kw,
2363 let prev_local_signed_commitment_tx = match <u8 as Readable>::read(reader)? {
2366 Some(read_local_tx!())
2368 _ => return Err(DecodeError::InvalidValue),
2370 let current_local_commitment_tx = read_local_tx!();
2372 let current_remote_commitment_number = <U48 as Readable>::read(reader)?.0;
2373 let current_local_commitment_number = <U48 as Readable>::read(reader)?.0;
2375 let payment_preimages_len: u64 = Readable::read(reader)?;
2376 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
2377 for _ in 0..payment_preimages_len {
2378 let preimage: PaymentPreimage = Readable::read(reader)?;
2379 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2380 if let Some(_) = payment_preimages.insert(hash, preimage) {
2381 return Err(DecodeError::InvalidValue);
2385 let pending_htlcs_updated_len: u64 = Readable::read(reader)?;
2386 let mut pending_htlcs_updated = Vec::with_capacity(cmp::min(pending_htlcs_updated_len as usize, MAX_ALLOC_SIZE / (32 + 8*3)));
2387 for _ in 0..pending_htlcs_updated_len {
2388 pending_htlcs_updated.push(Readable::read(reader)?);
2391 let pending_events_len: u64 = Readable::read(reader)?;
2392 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<events::Event>()));
2393 for _ in 0..pending_events_len {
2394 if let Some(event) = MaybeReadable::read(reader)? {
2395 pending_events.push(event);
2399 let last_block_hash: BlockHash = Readable::read(reader)?;
2401 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
2402 let mut onchain_events_waiting_threshold_conf = HashMap::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
2403 for _ in 0..waiting_threshold_conf_len {
2404 let height_target = Readable::read(reader)?;
2405 let events_len: u64 = Readable::read(reader)?;
2406 let mut events = Vec::with_capacity(cmp::min(events_len as usize, MAX_ALLOC_SIZE / 128));
2407 for _ in 0..events_len {
2408 let ev = match <u8 as Readable>::read(reader)? {
2410 let htlc_source = Readable::read(reader)?;
2411 let hash = Readable::read(reader)?;
2412 OnchainEvent::HTLCUpdate {
2413 htlc_update: (htlc_source, hash)
2417 let descriptor = Readable::read(reader)?;
2418 OnchainEvent::MaturingOutput {
2422 _ => return Err(DecodeError::InvalidValue),
2426 onchain_events_waiting_threshold_conf.insert(height_target, events);
2429 let outputs_to_watch_len: u64 = Readable::read(reader)?;
2430 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>>())));
2431 for _ in 0..outputs_to_watch_len {
2432 let txid = Readable::read(reader)?;
2433 let outputs_len: u64 = Readable::read(reader)?;
2434 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Script>()));
2435 for _ in 0..outputs_len {
2436 outputs.push(Readable::read(reader)?);
2438 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
2439 return Err(DecodeError::InvalidValue);
2442 let onchain_tx_handler = Readable::read(reader)?;
2444 let lockdown_from_offchain = Readable::read(reader)?;
2445 let local_tx_signed = Readable::read(reader)?;
2447 Ok((last_block_hash.clone(), ChannelMonitor {
2449 commitment_transaction_number_obscure_factor,
2452 broadcasted_local_revokable_script,
2453 remote_payment_script,
2458 current_remote_commitment_txid,
2459 prev_remote_commitment_txid,
2462 funding_redeemscript,
2463 channel_value_satoshis,
2464 their_cur_revocation_points,
2467 their_to_self_delay,
2470 remote_claimable_outpoints,
2471 remote_commitment_txn_on_chain,
2472 remote_hash_commitment_number,
2474 prev_local_signed_commitment_tx,
2475 current_local_commitment_tx,
2476 current_remote_commitment_number,
2477 current_local_commitment_number,
2480 pending_htlcs_updated,
2483 onchain_events_waiting_threshold_conf,
2488 lockdown_from_offchain,
2492 secp_ctx: Secp256k1::new(),
2499 use bitcoin::blockdata::script::{Script, Builder};
2500 use bitcoin::blockdata::opcodes;
2501 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, SigHashType};
2502 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
2503 use bitcoin::util::bip143;
2504 use bitcoin::hashes::Hash;
2505 use bitcoin::hashes::sha256::Hash as Sha256;
2506 use bitcoin::hashes::hex::FromHex;
2507 use bitcoin::hash_types::Txid;
2509 use chain::transaction::OutPoint;
2510 use ln::channelmanager::{PaymentPreimage, PaymentHash};
2511 use ln::channelmonitor::ChannelMonitor;
2512 use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
2514 use ln::chan_utils::{HTLCOutputInCommitment, LocalCommitmentTransaction};
2515 use util::test_utils::TestLogger;
2516 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
2517 use bitcoin::secp256k1::Secp256k1;
2518 use rand::{thread_rng,Rng};
2520 use chain::keysinterface::InMemoryChannelKeys;
2523 fn test_prune_preimages() {
2524 let secp_ctx = Secp256k1::new();
2525 let logger = Arc::new(TestLogger::new());
2527 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
2528 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2530 let mut preimages = Vec::new();
2532 let mut rng = thread_rng();
2534 let mut preimage = PaymentPreimage([0; 32]);
2535 rng.fill_bytes(&mut preimage.0[..]);
2536 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2537 preimages.push((preimage, hash));
2541 macro_rules! preimages_slice_to_htlc_outputs {
2542 ($preimages_slice: expr) => {
2544 let mut res = Vec::new();
2545 for (idx, preimage) in $preimages_slice.iter().enumerate() {
2546 res.push((HTLCOutputInCommitment {
2550 payment_hash: preimage.1.clone(),
2551 transaction_output_index: Some(idx as u32),
2558 macro_rules! preimages_to_local_htlcs {
2559 ($preimages_slice: expr) => {
2561 let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2562 let res: Vec<_> = inp.drain(..).map(|e| { (e.0, None, e.1) }).collect();
2568 macro_rules! test_preimages_exist {
2569 ($preimages_slice: expr, $monitor: expr) => {
2570 for preimage in $preimages_slice {
2571 assert!($monitor.payment_preimages.contains_key(&preimage.1));
2576 let keys = InMemoryChannelKeys::new(
2578 SecretKey::from_slice(&[41; 32]).unwrap(),
2579 SecretKey::from_slice(&[41; 32]).unwrap(),
2580 SecretKey::from_slice(&[41; 32]).unwrap(),
2581 SecretKey::from_slice(&[41; 32]).unwrap(),
2582 SecretKey::from_slice(&[41; 32]).unwrap(),
2588 // Prune with one old state and a local commitment tx holding a few overlaps with the
2590 let mut monitor = ChannelMonitor::new(keys,
2591 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()), 0, &Script::new(),
2592 (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
2593 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
2594 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
2595 10, Script::new(), 46, 0, LocalCommitmentTransaction::dummy());
2597 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..10])).unwrap();
2598 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
2599 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
2600 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
2601 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
2602 for &(ref preimage, ref hash) in preimages.iter() {
2603 monitor.provide_payment_preimage(hash, preimage);
2606 // Now provide a secret, pruning preimages 10-15
2607 let mut secret = [0; 32];
2608 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2609 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2610 assert_eq!(monitor.payment_preimages.len(), 15);
2611 test_preimages_exist!(&preimages[0..10], monitor);
2612 test_preimages_exist!(&preimages[15..20], monitor);
2614 // Now provide a further secret, pruning preimages 15-17
2615 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2616 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2617 assert_eq!(monitor.payment_preimages.len(), 13);
2618 test_preimages_exist!(&preimages[0..10], monitor);
2619 test_preimages_exist!(&preimages[17..20], monitor);
2621 // Now update local commitment tx info, pruning only element 18 as we still care about the
2622 // previous commitment tx's preimages too
2623 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..5])).unwrap();
2624 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2625 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2626 assert_eq!(monitor.payment_preimages.len(), 12);
2627 test_preimages_exist!(&preimages[0..10], monitor);
2628 test_preimages_exist!(&preimages[18..20], monitor);
2630 // But if we do it again, we'll prune 5-10
2631 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..3])).unwrap();
2632 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2633 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2634 assert_eq!(monitor.payment_preimages.len(), 5);
2635 test_preimages_exist!(&preimages[0..5], monitor);
2639 fn test_claim_txn_weight_computation() {
2640 // We test Claim txn weight, knowing that we want expected weigth and
2641 // not actual case to avoid sigs and time-lock delays hell variances.
2643 let secp_ctx = Secp256k1::new();
2644 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
2645 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
2646 let mut sum_actual_sigs = 0;
2648 macro_rules! sign_input {
2649 ($sighash_parts: expr, $input: expr, $idx: expr, $amount: expr, $input_type: expr, $sum_actual_sigs: expr) => {
2650 let htlc = HTLCOutputInCommitment {
2651 offered: if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::OfferedHTLC { true } else { false },
2653 cltv_expiry: 2 << 16,
2654 payment_hash: PaymentHash([1; 32]),
2655 transaction_output_index: Some($idx),
2657 let redeem_script = if *$input_type == InputDescriptors::RevokedOutput { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &pubkey, &pubkey, &pubkey) };
2658 let sighash = hash_to_message!(&$sighash_parts.sighash_all(&$input, &redeem_script, $amount)[..]);
2659 let sig = secp_ctx.sign(&sighash, &privkey);
2660 $input.witness.push(sig.serialize_der().to_vec());
2661 $input.witness[0].push(SigHashType::All as u8);
2662 sum_actual_sigs += $input.witness[0].len();
2663 if *$input_type == InputDescriptors::RevokedOutput {
2664 $input.witness.push(vec!(1));
2665 } else if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::RevokedReceivedHTLC {
2666 $input.witness.push(pubkey.clone().serialize().to_vec());
2667 } else if *$input_type == InputDescriptors::ReceivedHTLC {
2668 $input.witness.push(vec![0]);
2670 $input.witness.push(PaymentPreimage([1; 32]).0.to_vec());
2672 $input.witness.push(redeem_script.into_bytes());
2673 println!("witness[0] {}", $input.witness[0].len());
2674 println!("witness[1] {}", $input.witness[1].len());
2675 println!("witness[2] {}", $input.witness[2].len());
2679 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
2680 let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
2682 // Justice tx with 1 to_local, 2 revoked offered HTLCs, 1 revoked received HTLCs
2683 let mut claim_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2685 claim_tx.input.push(TxIn {
2686 previous_output: BitcoinOutPoint {
2690 script_sig: Script::new(),
2691 sequence: 0xfffffffd,
2692 witness: Vec::new(),
2695 claim_tx.output.push(TxOut {
2696 script_pubkey: script_pubkey.clone(),
2699 let base_weight = claim_tx.get_weight();
2700 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2701 let inputs_des = vec![InputDescriptors::RevokedOutput, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedReceivedHTLC];
2702 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2703 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2705 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));
2707 // Claim tx with 1 offered HTLCs, 3 received HTLCs
2708 claim_tx.input.clear();
2709 sum_actual_sigs = 0;
2711 claim_tx.input.push(TxIn {
2712 previous_output: BitcoinOutPoint {
2716 script_sig: Script::new(),
2717 sequence: 0xfffffffd,
2718 witness: Vec::new(),
2721 let base_weight = claim_tx.get_weight();
2722 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2723 let inputs_des = vec![InputDescriptors::OfferedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC];
2724 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2725 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2727 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));
2729 // Justice tx with 1 revoked HTLC-Success tx output
2730 claim_tx.input.clear();
2731 sum_actual_sigs = 0;
2732 claim_tx.input.push(TxIn {
2733 previous_output: BitcoinOutPoint {
2737 script_sig: Script::new(),
2738 sequence: 0xfffffffd,
2739 witness: Vec::new(),
2741 let base_weight = claim_tx.get_weight();
2742 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2743 let inputs_des = vec![InputDescriptors::RevokedOutput];
2744 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2745 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2747 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));
2750 // Further testing is done in the ChannelManager integration tests.