1 //! The logic to monitor for on-chain transactions and create the relevant claim responses lives
4 //! ChannelMonitor objects are generated by ChannelManager in response to relevant
5 //! messages/actions, and MUST be persisted to disk (and, preferably, remotely) before progress can
6 //! be made in responding to certain messages, see ManyChannelMonitor for more.
8 //! Note that ChannelMonitors are an important part of the lightning trust model and a copy of the
9 //! latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date
10 //! ChannelMonitors should do so). Thus, if you're building rust-lightning into an HSM or other
11 //! security-domain-separated system design, you should consider having multiple paths for
12 //! ChannelMonitors to get out of the HSM and onto monitoring devices.
14 use bitcoin::blockdata::block::BlockHeader;
15 use bitcoin::blockdata::transaction::{TxOut,Transaction};
16 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
17 use bitcoin::blockdata::script::{Script, Builder};
18 use bitcoin::blockdata::opcodes;
19 use bitcoin::consensus::encode;
20 use bitcoin::util::hash::BitcoinHash;
22 use bitcoin::hashes::Hash;
23 use bitcoin::hashes::sha256::Hash as Sha256;
24 use bitcoin::hash_types::{Txid, BlockHash, WPubkeyHash};
26 use bitcoin::secp256k1::{Secp256k1,Signature};
27 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
28 use bitcoin::secp256k1;
30 use ln::msgs::DecodeError;
32 use ln::chan_utils::{CounterpartyCommitmentSecrets, HTLCOutputInCommitment, LocalCommitmentTransaction, HTLCType};
33 use ln::channelmanager::{HTLCSource, PaymentPreimage, PaymentHash};
34 use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
35 use chain::chaininterface::{ChainListener, ChainWatchInterface, BroadcasterInterface, FeeEstimator};
36 use chain::transaction::OutPoint;
37 use chain::keysinterface::{SpendableOutputDescriptor, ChannelKeys};
38 use util::logger::Logger;
39 use util::ser::{Readable, MaybeReadable, Writer, Writeable, U48};
40 use util::{byte_utils, events};
42 use std::collections::{HashMap, hash_map};
44 use std::{hash,cmp, mem};
47 /// An update generated by the underlying Channel itself which contains some new information the
48 /// ChannelMonitor should be made aware of.
49 #[cfg_attr(test, derive(PartialEq))]
52 pub struct ChannelMonitorUpdate {
53 pub(super) updates: Vec<ChannelMonitorUpdateStep>,
54 /// The sequence number of this update. Updates *must* be replayed in-order according to this
55 /// sequence number (and updates may panic if they are not). The update_id values are strictly
56 /// increasing and increase by one for each new update.
58 /// This sequence number is also used to track up to which points updates which returned
59 /// ChannelMonitorUpdateErr::TemporaryFailure have been applied to all copies of a given
60 /// ChannelMonitor when ChannelManager::channel_monitor_updated is called.
64 impl Writeable for ChannelMonitorUpdate {
65 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
66 self.update_id.write(w)?;
67 (self.updates.len() as u64).write(w)?;
68 for update_step in self.updates.iter() {
69 update_step.write(w)?;
74 impl Readable for ChannelMonitorUpdate {
75 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
76 let update_id: u64 = Readable::read(r)?;
77 let len: u64 = Readable::read(r)?;
78 let mut updates = Vec::with_capacity(cmp::min(len as usize, MAX_ALLOC_SIZE / ::std::mem::size_of::<ChannelMonitorUpdateStep>()));
80 updates.push(Readable::read(r)?);
82 Ok(Self { update_id, updates })
86 /// An error enum representing a failure to persist a channel monitor update.
88 pub enum ChannelMonitorUpdateErr {
89 /// Used to indicate a temporary failure (eg connection to a watchtower or remote backup of
90 /// our state failed, but is expected to succeed at some point in the future).
92 /// Such a failure will "freeze" a channel, preventing us from revoking old states or
93 /// submitting new commitment transactions to the remote party. Once the update(s) which failed
94 /// have been successfully applied, ChannelManager::channel_monitor_updated can be used to
95 /// restore the channel to an operational state.
97 /// Note that a given ChannelManager will *never* re-generate a given ChannelMonitorUpdate. If
98 /// you return a TemporaryFailure you must ensure that it is written to disk safely before
99 /// writing out the latest ChannelManager state.
101 /// Even when a channel has been "frozen" updates to the ChannelMonitor can continue to occur
102 /// (eg if an inbound HTLC which we forwarded was claimed upstream resulting in us attempting
103 /// to claim it on this channel) and those updates must be applied wherever they can be. At
104 /// least one such updated ChannelMonitor must be persisted otherwise PermanentFailure should
105 /// be returned to get things on-chain ASAP using only the in-memory copy. Obviously updates to
106 /// the channel which would invalidate previous ChannelMonitors are not made when a channel has
109 /// Note that even if updates made after TemporaryFailure succeed you must still call
110 /// channel_monitor_updated to ensure you have the latest monitor and re-enable normal channel
113 /// Note that the update being processed here will not be replayed for you when you call
114 /// ChannelManager::channel_monitor_updated, so you must store the update itself along
115 /// with the persisted ChannelMonitor on your own local disk prior to returning a
116 /// TemporaryFailure. You may, of course, employ a journaling approach, storing only the
117 /// ChannelMonitorUpdate on disk without updating the monitor itself, replaying the journal at
120 /// For deployments where a copy of ChannelMonitors and other local state are backed up in a
121 /// remote location (with local copies persisted immediately), it is anticipated that all
122 /// updates will return TemporaryFailure until the remote copies could be updated.
124 /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
125 /// different watchtower and cannot update with all watchtowers that were previously informed
126 /// of this channel). This will force-close the channel in question (which will generate one
127 /// final ChannelMonitorUpdate which must be delivered to at least one ChannelMonitor copy).
129 /// Should also be used to indicate a failure to update the local persisted copy of the channel
134 /// General Err type for ChannelMonitor actions. Generally, this implies that the data provided is
135 /// inconsistent with the ChannelMonitor being called. eg for ChannelMonitor::update_monitor this
136 /// means you tried to update a monitor for a different channel or the ChannelMonitorUpdate was
138 /// Contains a human-readable error message.
140 pub struct MonitorUpdateError(pub &'static str);
142 /// Simple structure send back by ManyChannelMonitor in case of HTLC detected onchain from a
143 /// forward channel and from which info are needed to update HTLC in a backward channel.
144 #[derive(Clone, PartialEq)]
145 pub struct HTLCUpdate {
146 pub(super) payment_hash: PaymentHash,
147 pub(super) payment_preimage: Option<PaymentPreimage>,
148 pub(super) source: HTLCSource
150 impl_writeable!(HTLCUpdate, 0, { payment_hash, payment_preimage, source });
152 /// 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 /// Cache remote basepoint to compute any transaction on
432 /// remote outputs, either justice or preimage/timeout transactions.
434 struct RemoteTxCache {
435 remote_delayed_payment_base_key: PublicKey,
436 remote_htlc_base_key: PublicKey,
437 per_htlc: HashMap<Txid, Vec<HTLCOutputInCommitment>>
440 /// When ChannelMonitor discovers an onchain outpoint being a step of a channel and that it needs
441 /// to generate a tx to push channel state forward, we cache outpoint-solving tx material to build
442 /// a new bumped one in case of lenghty confirmation delay
443 #[derive(Clone, PartialEq)]
444 pub(crate) enum InputMaterial {
446 per_commitment_point: PublicKey,
447 remote_delayed_payment_base_key: PublicKey,
448 remote_htlc_base_key: PublicKey,
449 per_commitment_key: SecretKey,
450 input_descriptor: InputDescriptors,
452 htlc: Option<HTLCOutputInCommitment>
455 per_commitment_point: PublicKey,
456 remote_delayed_payment_base_key: PublicKey,
457 remote_htlc_base_key: PublicKey,
458 preimage: Option<PaymentPreimage>,
459 htlc: HTLCOutputInCommitment
462 preimage: Option<PaymentPreimage>,
466 funding_redeemscript: Script,
470 impl Writeable for InputMaterial {
471 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
473 &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} => {
474 writer.write_all(&[0; 1])?;
475 per_commitment_point.write(writer)?;
476 remote_delayed_payment_base_key.write(writer)?;
477 remote_htlc_base_key.write(writer)?;
478 writer.write_all(&per_commitment_key[..])?;
479 input_descriptor.write(writer)?;
480 writer.write_all(&byte_utils::be64_to_array(*amount))?;
483 &InputMaterial::RemoteHTLC { ref per_commitment_point, ref remote_delayed_payment_base_key, ref remote_htlc_base_key, ref preimage, ref htlc} => {
484 writer.write_all(&[1; 1])?;
485 per_commitment_point.write(writer)?;
486 remote_delayed_payment_base_key.write(writer)?;
487 remote_htlc_base_key.write(writer)?;
488 preimage.write(writer)?;
491 &InputMaterial::LocalHTLC { ref preimage, ref amount } => {
492 writer.write_all(&[2; 1])?;
493 preimage.write(writer)?;
494 writer.write_all(&byte_utils::be64_to_array(*amount))?;
496 &InputMaterial::Funding { ref funding_redeemscript } => {
497 writer.write_all(&[3; 1])?;
498 funding_redeemscript.write(writer)?;
505 impl Readable for InputMaterial {
506 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
507 let input_material = match <u8 as Readable>::read(reader)? {
509 let per_commitment_point = Readable::read(reader)?;
510 let remote_delayed_payment_base_key = Readable::read(reader)?;
511 let remote_htlc_base_key = Readable::read(reader)?;
512 let per_commitment_key = Readable::read(reader)?;
513 let input_descriptor = Readable::read(reader)?;
514 let amount = Readable::read(reader)?;
515 let htlc = Readable::read(reader)?;
516 InputMaterial::Revoked {
517 per_commitment_point,
518 remote_delayed_payment_base_key,
519 remote_htlc_base_key,
527 let per_commitment_point = Readable::read(reader)?;
528 let remote_delayed_payment_base_key = Readable::read(reader)?;
529 let remote_htlc_base_key = Readable::read(reader)?;
530 let preimage = Readable::read(reader)?;
531 let htlc = Readable::read(reader)?;
532 InputMaterial::RemoteHTLC {
533 per_commitment_point,
534 remote_delayed_payment_base_key,
535 remote_htlc_base_key,
541 let preimage = Readable::read(reader)?;
542 let amount = Readable::read(reader)?;
543 InputMaterial::LocalHTLC {
549 InputMaterial::Funding {
550 funding_redeemscript: Readable::read(reader)?,
553 _ => return Err(DecodeError::InvalidValue),
559 /// ClaimRequest is a descriptor structure to communicate between detection
560 /// and reaction module. They are generated by ChannelMonitor while parsing
561 /// onchain txn leaked from a channel and handed over to OnchainTxHandler which
562 /// is responsible for opportunistic aggregation, selecting and enforcing
563 /// bumping logic, building and signing transactions.
564 pub(crate) struct ClaimRequest {
565 // Block height before which claiming is exclusive to one party,
566 // after reaching it, claiming may be contentious.
567 pub(crate) absolute_timelock: u32,
568 // Timeout tx must have nLocktime set which means aggregating multiple
569 // ones must take the higher nLocktime among them to satisfy all of them.
570 // Sadly it has few pitfalls, a) it takes longuer to get fund back b) CLTV_DELTA
571 // of a sooner-HTLC could be swallowed by the highest nLocktime of the HTLC set.
572 // Do simplify we mark them as non-aggregable.
573 pub(crate) aggregable: bool,
574 // Basic bitcoin outpoint (txid, vout)
575 pub(crate) outpoint: BitcoinOutPoint,
576 // Following outpoint type, set of data needed to generate transaction digest
577 // and satisfy witness program.
578 pub(crate) witness_data: InputMaterial
581 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
582 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
583 #[derive(Clone, PartialEq)]
585 /// HTLC output getting solved by a timeout, at maturation we pass upstream payment source information to solve
586 /// inbound HTLC in backward channel. Note, in case of preimage, we pass info to upstream without delay as we can
587 /// only win from it, so it's never an OnchainEvent
589 htlc_update: (HTLCSource, PaymentHash),
592 descriptor: SpendableOutputDescriptor,
596 const SERIALIZATION_VERSION: u8 = 1;
597 const MIN_SERIALIZATION_VERSION: u8 = 1;
599 #[cfg_attr(test, derive(PartialEq))]
601 pub(super) enum ChannelMonitorUpdateStep {
602 LatestLocalCommitmentTXInfo {
603 commitment_tx: LocalCommitmentTransaction,
604 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
606 LatestRemoteCommitmentTXInfo {
607 unsigned_commitment_tx: Transaction, // TODO: We should actually only need the txid here
608 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
609 commitment_number: u64,
610 their_revocation_point: PublicKey,
613 payment_preimage: PaymentPreimage,
619 /// Used to indicate that the no future updates will occur, and likely that the latest local
620 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
622 /// If set to false, we shouldn't broadcast the latest local commitment transaction as we
623 /// think we've fallen behind!
624 should_broadcast: bool,
628 impl Writeable for ChannelMonitorUpdateStep {
629 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
631 &ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { ref commitment_tx, ref htlc_outputs } => {
633 commitment_tx.write(w)?;
634 (htlc_outputs.len() as u64).write(w)?;
635 for &(ref output, ref signature, ref source) in htlc_outputs.iter() {
641 &ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { ref unsigned_commitment_tx, ref htlc_outputs, ref commitment_number, ref their_revocation_point } => {
643 unsigned_commitment_tx.write(w)?;
644 commitment_number.write(w)?;
645 their_revocation_point.write(w)?;
646 (htlc_outputs.len() as u64).write(w)?;
647 for &(ref output, ref source) in htlc_outputs.iter() {
649 source.as_ref().map(|b| b.as_ref()).write(w)?;
652 &ChannelMonitorUpdateStep::PaymentPreimage { ref payment_preimage } => {
654 payment_preimage.write(w)?;
656 &ChannelMonitorUpdateStep::CommitmentSecret { ref idx, ref secret } => {
661 &ChannelMonitorUpdateStep::ChannelForceClosed { ref should_broadcast } => {
663 should_broadcast.write(w)?;
669 impl Readable for ChannelMonitorUpdateStep {
670 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
671 match Readable::read(r)? {
673 Ok(ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo {
674 commitment_tx: Readable::read(r)?,
676 let len: u64 = Readable::read(r)?;
677 let mut res = Vec::new();
679 res.push((Readable::read(r)?, Readable::read(r)?, Readable::read(r)?));
686 Ok(ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo {
687 unsigned_commitment_tx: Readable::read(r)?,
688 commitment_number: Readable::read(r)?,
689 their_revocation_point: Readable::read(r)?,
691 let len: u64 = Readable::read(r)?;
692 let mut res = Vec::new();
694 res.push((Readable::read(r)?, <Option<HTLCSource> as Readable>::read(r)?.map(|o| Box::new(o))));
701 Ok(ChannelMonitorUpdateStep::PaymentPreimage {
702 payment_preimage: Readable::read(r)?,
706 Ok(ChannelMonitorUpdateStep::CommitmentSecret {
707 idx: Readable::read(r)?,
708 secret: Readable::read(r)?,
712 Ok(ChannelMonitorUpdateStep::ChannelForceClosed {
713 should_broadcast: Readable::read(r)?
716 _ => Err(DecodeError::InvalidValue),
721 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
722 /// on-chain transactions to ensure no loss of funds occurs.
724 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
725 /// information and are actively monitoring the chain.
727 /// Pending Events or updated HTLCs which have not yet been read out by
728 /// get_and_clear_pending_htlcs_updated or get_and_clear_pending_events are serialized to disk and
729 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
730 /// gotten are fully handled before re-serializing the new state.
731 pub struct ChannelMonitor<ChanSigner: ChannelKeys> {
732 latest_update_id: u64,
733 commitment_transaction_number_obscure_factor: u64,
735 destination_script: Script,
736 broadcasted_local_revokable_script: Option<(Script, PublicKey, PublicKey)>,
737 remote_payment_script: Script,
738 shutdown_script: Script,
741 funding_info: (OutPoint, Script),
742 current_remote_commitment_txid: Option<Txid>,
743 prev_remote_commitment_txid: Option<Txid>,
745 remote_tx_cache: RemoteTxCache,
746 funding_redeemscript: Script,
747 channel_value_satoshis: u64,
748 // first is the idx of the first of the two revocation points
749 their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
751 our_to_self_delay: u16,
752 their_to_self_delay: u16,
754 commitment_secrets: CounterpartyCommitmentSecrets,
755 remote_claimable_outpoints: HashMap<Txid, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
756 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
757 /// Nor can we figure out their commitment numbers without the commitment transaction they are
758 /// spending. Thus, in order to claim them via revocation key, we track all the remote
759 /// commitment transactions which we find on-chain, mapping them to the commitment number which
760 /// can be used to derive the revocation key and claim the transactions.
761 remote_commitment_txn_on_chain: HashMap<Txid, (u64, Vec<Script>)>,
762 /// Cache used to make pruning of payment_preimages faster.
763 /// Maps payment_hash values to commitment numbers for remote transactions for non-revoked
764 /// remote transactions (ie should remain pretty small).
765 /// Serialized to disk but should generally not be sent to Watchtowers.
766 remote_hash_commitment_number: HashMap<PaymentHash, u64>,
768 // We store two local commitment transactions to avoid any race conditions where we may update
769 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
770 // various monitors for one channel being out of sync, and us broadcasting a local
771 // transaction for which we have deleted claim information on some watchtowers.
772 prev_local_signed_commitment_tx: Option<LocalSignedTx>,
773 current_local_commitment_tx: LocalSignedTx,
775 // Used just for ChannelManager to make sure it has the latest channel data during
777 current_remote_commitment_number: u64,
778 // Used just for ChannelManager to make sure it has the latest channel data during
780 current_local_commitment_number: u64,
782 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
784 pending_htlcs_updated: Vec<HTLCUpdate>,
785 pending_events: Vec<events::Event>,
787 // Used to track onchain events, i.e transactions parts of channels confirmed on chain, on which
788 // we have to take actions once they reach enough confs. Key is a block height timer, i.e we enforce
789 // actions when we receive a block with given height. Actions depend on OnchainEvent type.
790 onchain_events_waiting_threshold_conf: HashMap<u32, Vec<OnchainEvent>>,
792 // If we get serialized out and re-read, we need to make sure that the chain monitoring
793 // interface knows about the TXOs that we want to be notified of spends of. We could probably
794 // be smart and derive them from the above storage fields, but its much simpler and more
795 // Obviously Correct (tm) if we just keep track of them explicitly.
796 outputs_to_watch: HashMap<Txid, Vec<Script>>,
799 pub onchain_tx_handler: OnchainTxHandler<ChanSigner>,
801 onchain_tx_handler: OnchainTxHandler<ChanSigner>,
803 // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
804 // channel has been force-closed. After this is set, no further local commitment transaction
805 // updates may occur, and we panic!() if one is provided.
806 lockdown_from_offchain: bool,
808 // Set once we've signed a local commitment transaction and handed it over to our
809 // OnchainTxHandler. After this is set, no future updates to our local commitment transactions
810 // may occur, and we fail any such monitor updates.
811 local_tx_signed: bool,
813 // We simply modify last_block_hash in Channel's block_connected so that serialization is
814 // consistent but hopefully the users' copy handles block_connected in a consistent way.
815 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
816 // their last_block_hash from its state and not based on updated copies that didn't run through
817 // the full block_connected).
818 pub(crate) last_block_hash: BlockHash,
819 secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
822 #[cfg(any(test, feature = "fuzztarget"))]
823 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
824 /// underlying object
825 impl<ChanSigner: ChannelKeys> PartialEq for ChannelMonitor<ChanSigner> {
826 fn eq(&self, other: &Self) -> bool {
827 if self.latest_update_id != other.latest_update_id ||
828 self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
829 self.destination_script != other.destination_script ||
830 self.broadcasted_local_revokable_script != other.broadcasted_local_revokable_script ||
831 self.remote_payment_script != other.remote_payment_script ||
832 self.keys.pubkeys() != other.keys.pubkeys() ||
833 self.funding_info != other.funding_info ||
834 self.current_remote_commitment_txid != other.current_remote_commitment_txid ||
835 self.prev_remote_commitment_txid != other.prev_remote_commitment_txid ||
836 self.remote_tx_cache != other.remote_tx_cache ||
837 self.funding_redeemscript != other.funding_redeemscript ||
838 self.channel_value_satoshis != other.channel_value_satoshis ||
839 self.their_cur_revocation_points != other.their_cur_revocation_points ||
840 self.our_to_self_delay != other.our_to_self_delay ||
841 self.their_to_self_delay != other.their_to_self_delay ||
842 self.commitment_secrets != other.commitment_secrets ||
843 self.remote_claimable_outpoints != other.remote_claimable_outpoints ||
844 self.remote_commitment_txn_on_chain != other.remote_commitment_txn_on_chain ||
845 self.remote_hash_commitment_number != other.remote_hash_commitment_number ||
846 self.prev_local_signed_commitment_tx != other.prev_local_signed_commitment_tx ||
847 self.current_remote_commitment_number != other.current_remote_commitment_number ||
848 self.current_local_commitment_number != other.current_local_commitment_number ||
849 self.current_local_commitment_tx != other.current_local_commitment_tx ||
850 self.payment_preimages != other.payment_preimages ||
851 self.pending_htlcs_updated != other.pending_htlcs_updated ||
852 self.pending_events.len() != other.pending_events.len() || // We trust events to round-trip properly
853 self.onchain_events_waiting_threshold_conf != other.onchain_events_waiting_threshold_conf ||
854 self.outputs_to_watch != other.outputs_to_watch ||
855 self.lockdown_from_offchain != other.lockdown_from_offchain ||
856 self.local_tx_signed != other.local_tx_signed
865 impl<ChanSigner: ChannelKeys + Writeable> ChannelMonitor<ChanSigner> {
866 /// Writes this monitor into the given writer, suitable for writing to disk.
868 /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
869 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
870 /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
871 /// returned block hash and the the current chain and then reconnecting blocks to get to the
872 /// best chain) upon deserializing the object!
873 pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
874 //TODO: We still write out all the serialization here manually instead of using the fancy
875 //serialization framework we have, we should migrate things over to it.
876 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
877 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
879 self.latest_update_id.write(writer)?;
881 // Set in initial Channel-object creation, so should always be set by now:
882 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
884 self.destination_script.write(writer)?;
885 if let Some(ref broadcasted_local_revokable_script) = self.broadcasted_local_revokable_script {
886 writer.write_all(&[0; 1])?;
887 broadcasted_local_revokable_script.0.write(writer)?;
888 broadcasted_local_revokable_script.1.write(writer)?;
889 broadcasted_local_revokable_script.2.write(writer)?;
891 writer.write_all(&[1; 1])?;
894 self.remote_payment_script.write(writer)?;
895 self.shutdown_script.write(writer)?;
897 self.keys.write(writer)?;
898 writer.write_all(&self.funding_info.0.txid[..])?;
899 writer.write_all(&byte_utils::be16_to_array(self.funding_info.0.index))?;
900 self.funding_info.1.write(writer)?;
901 self.current_remote_commitment_txid.write(writer)?;
902 self.prev_remote_commitment_txid.write(writer)?;
904 self.remote_tx_cache.remote_delayed_payment_base_key.write(writer)?;
905 self.remote_tx_cache.remote_htlc_base_key.write(writer)?;
906 writer.write_all(&byte_utils::be64_to_array(self.remote_tx_cache.per_htlc.len() as u64))?;
907 for (ref txid, ref htlcs) in self.remote_tx_cache.per_htlc.iter() {
908 writer.write_all(&txid[..])?;
909 writer.write_all(&byte_utils::be64_to_array(htlcs.len() as u64))?;
910 for &ref htlc in htlcs.iter() {
914 self.funding_redeemscript.write(writer)?;
915 self.channel_value_satoshis.write(writer)?;
917 match self.their_cur_revocation_points {
918 Some((idx, pubkey, second_option)) => {
919 writer.write_all(&byte_utils::be48_to_array(idx))?;
920 writer.write_all(&pubkey.serialize())?;
921 match second_option {
922 Some(second_pubkey) => {
923 writer.write_all(&second_pubkey.serialize())?;
926 writer.write_all(&[0; 33])?;
931 writer.write_all(&byte_utils::be48_to_array(0))?;
935 writer.write_all(&byte_utils::be16_to_array(self.our_to_self_delay))?;
936 writer.write_all(&byte_utils::be16_to_array(self.their_to_self_delay))?;
938 self.commitment_secrets.write(writer)?;
940 macro_rules! serialize_htlc_in_commitment {
941 ($htlc_output: expr) => {
942 writer.write_all(&[$htlc_output.offered as u8; 1])?;
943 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
944 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
945 writer.write_all(&$htlc_output.payment_hash.0[..])?;
946 $htlc_output.transaction_output_index.write(writer)?;
950 writer.write_all(&byte_utils::be64_to_array(self.remote_claimable_outpoints.len() as u64))?;
951 for (ref txid, ref htlc_infos) in self.remote_claimable_outpoints.iter() {
952 writer.write_all(&txid[..])?;
953 writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
954 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
955 serialize_htlc_in_commitment!(htlc_output);
956 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
960 writer.write_all(&byte_utils::be64_to_array(self.remote_commitment_txn_on_chain.len() as u64))?;
961 for (ref txid, &(commitment_number, ref txouts)) in self.remote_commitment_txn_on_chain.iter() {
962 writer.write_all(&txid[..])?;
963 writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
964 (txouts.len() as u64).write(writer)?;
965 for script in txouts.iter() {
966 script.write(writer)?;
970 writer.write_all(&byte_utils::be64_to_array(self.remote_hash_commitment_number.len() as u64))?;
971 for (ref payment_hash, commitment_number) in self.remote_hash_commitment_number.iter() {
972 writer.write_all(&payment_hash.0[..])?;
973 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
976 macro_rules! serialize_local_tx {
977 ($local_tx: expr) => {
978 $local_tx.txid.write(writer)?;
979 writer.write_all(&$local_tx.revocation_key.serialize())?;
980 writer.write_all(&$local_tx.a_htlc_key.serialize())?;
981 writer.write_all(&$local_tx.b_htlc_key.serialize())?;
982 writer.write_all(&$local_tx.delayed_payment_key.serialize())?;
983 writer.write_all(&$local_tx.per_commitment_point.serialize())?;
985 writer.write_all(&byte_utils::be64_to_array($local_tx.feerate_per_kw))?;
986 writer.write_all(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64))?;
987 for &(ref htlc_output, ref sig, ref htlc_source) in $local_tx.htlc_outputs.iter() {
988 serialize_htlc_in_commitment!(htlc_output);
989 if let &Some(ref their_sig) = sig {
991 writer.write_all(&their_sig.serialize_compact())?;
995 htlc_source.write(writer)?;
1000 if let Some(ref prev_local_tx) = self.prev_local_signed_commitment_tx {
1001 writer.write_all(&[1; 1])?;
1002 serialize_local_tx!(prev_local_tx);
1004 writer.write_all(&[0; 1])?;
1007 serialize_local_tx!(self.current_local_commitment_tx);
1009 writer.write_all(&byte_utils::be48_to_array(self.current_remote_commitment_number))?;
1010 writer.write_all(&byte_utils::be48_to_array(self.current_local_commitment_number))?;
1012 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
1013 for payment_preimage in self.payment_preimages.values() {
1014 writer.write_all(&payment_preimage.0[..])?;
1017 writer.write_all(&byte_utils::be64_to_array(self.pending_htlcs_updated.len() as u64))?;
1018 for data in self.pending_htlcs_updated.iter() {
1019 data.write(writer)?;
1022 writer.write_all(&byte_utils::be64_to_array(self.pending_events.len() as u64))?;
1023 for event in self.pending_events.iter() {
1024 event.write(writer)?;
1027 self.last_block_hash.write(writer)?;
1029 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_waiting_threshold_conf.len() as u64))?;
1030 for (ref target, ref events) in self.onchain_events_waiting_threshold_conf.iter() {
1031 writer.write_all(&byte_utils::be32_to_array(**target))?;
1032 writer.write_all(&byte_utils::be64_to_array(events.len() as u64))?;
1033 for ev in events.iter() {
1035 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1037 htlc_update.0.write(writer)?;
1038 htlc_update.1.write(writer)?;
1040 OnchainEvent::MaturingOutput { ref descriptor } => {
1042 descriptor.write(writer)?;
1048 (self.outputs_to_watch.len() as u64).write(writer)?;
1049 for (txid, output_scripts) in self.outputs_to_watch.iter() {
1050 txid.write(writer)?;
1051 (output_scripts.len() as u64).write(writer)?;
1052 for script in output_scripts.iter() {
1053 script.write(writer)?;
1056 self.onchain_tx_handler.write(writer)?;
1058 self.lockdown_from_offchain.write(writer)?;
1059 self.local_tx_signed.write(writer)?;
1065 impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
1066 pub(super) fn new(keys: ChanSigner, shutdown_pubkey: &PublicKey,
1067 our_to_self_delay: u16, destination_script: &Script, funding_info: (OutPoint, Script),
1068 remote_htlc_base_key: &PublicKey, remote_delayed_payment_base_key: &PublicKey,
1069 their_to_self_delay: u16, funding_redeemscript: Script, channel_value_satoshis: u64,
1070 commitment_transaction_number_obscure_factor: u64,
1071 initial_local_commitment_tx: LocalCommitmentTransaction) -> ChannelMonitor<ChanSigner> {
1073 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
1074 let our_channel_close_key_hash = WPubkeyHash::hash(&shutdown_pubkey.serialize());
1075 let shutdown_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
1076 let payment_key_hash = WPubkeyHash::hash(&keys.pubkeys().payment_point.serialize());
1077 let remote_payment_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_key_hash[..]).into_script();
1079 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() };
1081 let mut onchain_tx_handler = OnchainTxHandler::new(destination_script.clone(), keys.clone(), their_to_self_delay, our_to_self_delay);
1083 let local_tx_sequence = initial_local_commitment_tx.unsigned_tx.input[0].sequence as u64;
1084 let local_tx_locktime = initial_local_commitment_tx.unsigned_tx.lock_time as u64;
1085 let local_commitment_tx = LocalSignedTx {
1086 txid: initial_local_commitment_tx.txid(),
1087 revocation_key: initial_local_commitment_tx.local_keys.revocation_key,
1088 a_htlc_key: initial_local_commitment_tx.local_keys.a_htlc_key,
1089 b_htlc_key: initial_local_commitment_tx.local_keys.b_htlc_key,
1090 delayed_payment_key: initial_local_commitment_tx.local_keys.a_delayed_payment_key,
1091 per_commitment_point: initial_local_commitment_tx.local_keys.per_commitment_point,
1092 feerate_per_kw: initial_local_commitment_tx.feerate_per_kw,
1093 htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
1095 // Returning a monitor error before updating tracking points means in case of using
1096 // a concurrent watchtower implementation for same channel, if this one doesn't
1097 // reject update as we do, you MAY have the latest local valid commitment tx onchain
1098 // for which you want to spend outputs. We're NOT robust again this scenario right
1099 // now but we should consider it later.
1100 onchain_tx_handler.provide_latest_local_tx(initial_local_commitment_tx).unwrap();
1103 latest_update_id: 0,
1104 commitment_transaction_number_obscure_factor,
1106 destination_script: destination_script.clone(),
1107 broadcasted_local_revokable_script: None,
1108 remote_payment_script,
1113 current_remote_commitment_txid: None,
1114 prev_remote_commitment_txid: None,
1117 funding_redeemscript,
1118 channel_value_satoshis: channel_value_satoshis,
1119 their_cur_revocation_points: None,
1122 their_to_self_delay,
1124 commitment_secrets: CounterpartyCommitmentSecrets::new(),
1125 remote_claimable_outpoints: HashMap::new(),
1126 remote_commitment_txn_on_chain: HashMap::new(),
1127 remote_hash_commitment_number: HashMap::new(),
1129 prev_local_signed_commitment_tx: None,
1130 current_local_commitment_tx: local_commitment_tx,
1131 current_remote_commitment_number: 1 << 48,
1132 current_local_commitment_number: 0xffff_ffff_ffff - ((((local_tx_sequence & 0xffffff) << 3*8) | (local_tx_locktime as u64 & 0xffffff)) ^ commitment_transaction_number_obscure_factor),
1134 payment_preimages: HashMap::new(),
1135 pending_htlcs_updated: Vec::new(),
1136 pending_events: Vec::new(),
1138 onchain_events_waiting_threshold_conf: HashMap::new(),
1139 outputs_to_watch: HashMap::new(),
1143 lockdown_from_offchain: false,
1144 local_tx_signed: false,
1146 last_block_hash: Default::default(),
1147 secp_ctx: Secp256k1::new(),
1151 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
1152 /// needed by local commitment transactions HTCLs nor by remote ones. Unless we haven't already seen remote
1153 /// commitment transaction's secret, they are de facto pruned (we can use revocation key).
1154 pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
1155 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
1156 return Err(MonitorUpdateError("Previous secret did not match new one"));
1159 // Prune HTLCs from the previous remote commitment tx so we don't generate failure/fulfill
1160 // events for now-revoked/fulfilled HTLCs.
1161 if let Some(txid) = self.prev_remote_commitment_txid.take() {
1162 for &mut (_, ref mut source) in self.remote_claimable_outpoints.get_mut(&txid).unwrap() {
1167 if !self.payment_preimages.is_empty() {
1168 let cur_local_signed_commitment_tx = &self.current_local_commitment_tx;
1169 let prev_local_signed_commitment_tx = self.prev_local_signed_commitment_tx.as_ref();
1170 let min_idx = self.get_min_seen_secret();
1171 let remote_hash_commitment_number = &mut self.remote_hash_commitment_number;
1173 self.payment_preimages.retain(|&k, _| {
1174 for &(ref htlc, _, _) in cur_local_signed_commitment_tx.htlc_outputs.iter() {
1175 if k == htlc.payment_hash {
1179 if let Some(prev_local_commitment_tx) = prev_local_signed_commitment_tx {
1180 for &(ref htlc, _, _) in prev_local_commitment_tx.htlc_outputs.iter() {
1181 if k == htlc.payment_hash {
1186 let contains = if let Some(cn) = remote_hash_commitment_number.get(&k) {
1193 remote_hash_commitment_number.remove(&k);
1202 /// Informs this monitor of the latest remote (ie non-broadcastable) commitment transaction.
1203 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
1204 /// possibly future revocation/preimage information) to claim outputs where possible.
1205 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
1206 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 {
1207 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
1208 // so that a remote monitor doesn't learn anything unless there is a malicious close.
1209 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
1211 for &(ref htlc, _) in &htlc_outputs {
1212 self.remote_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
1215 let new_txid = unsigned_commitment_tx.txid();
1216 log_trace!(logger, "Tracking new remote commitment transaction with txid {} at commitment number {} with {} HTLC outputs", new_txid, commitment_number, htlc_outputs.len());
1217 log_trace!(logger, "New potential remote commitment transaction: {}", encode::serialize_hex(unsigned_commitment_tx));
1218 self.prev_remote_commitment_txid = self.current_remote_commitment_txid.take();
1219 self.current_remote_commitment_txid = Some(new_txid);
1220 self.remote_claimable_outpoints.insert(new_txid, htlc_outputs.clone());
1221 self.current_remote_commitment_number = commitment_number;
1222 //TODO: Merge this into the other per-remote-transaction output storage stuff
1223 match self.their_cur_revocation_points {
1224 Some(old_points) => {
1225 if old_points.0 == commitment_number + 1 {
1226 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
1227 } else if old_points.0 == commitment_number + 2 {
1228 if let Some(old_second_point) = old_points.2 {
1229 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
1231 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1234 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1238 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1241 let mut htlcs = Vec::with_capacity(htlc_outputs.len());
1242 for htlc in htlc_outputs {
1243 if htlc.0.transaction_output_index.is_some() {
1247 self.remote_tx_cache.per_htlc.insert(new_txid, htlcs);
1250 /// Informs this monitor of the latest local (ie broadcastable) commitment transaction. The
1251 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
1252 /// is important that any clones of this channel monitor (including remote clones) by kept
1253 /// up-to-date as our local commitment transaction is updated.
1254 /// Panics if set_their_to_self_delay has never been called.
1255 pub(super) fn provide_latest_local_commitment_tx_info(&mut self, commitment_tx: LocalCommitmentTransaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), MonitorUpdateError> {
1256 if self.local_tx_signed {
1257 return Err(MonitorUpdateError("A local commitment tx has already been signed, no new local commitment txn can be sent to our counterparty"));
1259 let txid = commitment_tx.txid();
1260 let sequence = commitment_tx.unsigned_tx.input[0].sequence as u64;
1261 let locktime = commitment_tx.unsigned_tx.lock_time as u64;
1262 let mut new_local_commitment_tx = LocalSignedTx {
1264 revocation_key: commitment_tx.local_keys.revocation_key,
1265 a_htlc_key: commitment_tx.local_keys.a_htlc_key,
1266 b_htlc_key: commitment_tx.local_keys.b_htlc_key,
1267 delayed_payment_key: commitment_tx.local_keys.a_delayed_payment_key,
1268 per_commitment_point: commitment_tx.local_keys.per_commitment_point,
1269 feerate_per_kw: commitment_tx.feerate_per_kw,
1270 htlc_outputs: htlc_outputs,
1272 // Returning a monitor error before updating tracking points means in case of using
1273 // a concurrent watchtower implementation for same channel, if this one doesn't
1274 // reject update as we do, you MAY have the latest local valid commitment tx onchain
1275 // for which you want to spend outputs. We're NOT robust again this scenario right
1276 // now but we should consider it later.
1277 if let Err(_) = self.onchain_tx_handler.provide_latest_local_tx(commitment_tx) {
1278 return Err(MonitorUpdateError("Local commitment signed has already been signed, no further update of LOCAL commitment transaction is allowed"));
1280 self.current_local_commitment_number = 0xffff_ffff_ffff - ((((sequence & 0xffffff) << 3*8) | (locktime as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
1281 mem::swap(&mut new_local_commitment_tx, &mut self.current_local_commitment_tx);
1282 self.prev_local_signed_commitment_tx = Some(new_local_commitment_tx);
1286 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
1287 /// commitment_tx_infos which contain the payment hash have been revoked.
1288 pub(super) fn provide_payment_preimage(&mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage) {
1289 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
1292 pub(super) fn broadcast_latest_local_commitment_txn<B: Deref, L: Deref>(&mut self, broadcaster: &B, logger: &L)
1293 where B::Target: BroadcasterInterface,
1296 for tx in self.get_latest_local_commitment_txn(logger).iter() {
1297 broadcaster.broadcast_transaction(tx);
1301 /// Used in Channel to cheat wrt the update_ids since it plays games, will be removed soon!
1302 pub(super) fn update_monitor_ooo<L: Deref>(&mut self, mut updates: ChannelMonitorUpdate, logger: &L) -> Result<(), MonitorUpdateError> where L::Target: Logger {
1303 for update in updates.updates.drain(..) {
1305 ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { commitment_tx, htlc_outputs } => {
1306 if self.lockdown_from_offchain { panic!(); }
1307 self.provide_latest_local_commitment_tx_info(commitment_tx, htlc_outputs)?
1309 ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
1310 self.provide_latest_remote_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point, logger),
1311 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
1312 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
1313 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
1314 self.provide_secret(idx, secret)?,
1315 ChannelMonitorUpdateStep::ChannelForceClosed { .. } => {},
1318 self.latest_update_id = updates.update_id;
1322 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
1325 /// panics if the given update is not the next update by update_id.
1326 pub fn update_monitor<B: Deref, L: Deref>(&mut self, mut updates: ChannelMonitorUpdate, broadcaster: &B, logger: &L) -> Result<(), MonitorUpdateError>
1327 where B::Target: BroadcasterInterface,
1330 if self.latest_update_id + 1 != updates.update_id {
1331 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
1333 for update in updates.updates.drain(..) {
1335 ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { commitment_tx, htlc_outputs } => {
1336 if self.lockdown_from_offchain { panic!(); }
1337 self.provide_latest_local_commitment_tx_info(commitment_tx, htlc_outputs)?
1339 ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
1340 self.provide_latest_remote_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point, logger),
1341 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
1342 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
1343 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
1344 self.provide_secret(idx, secret)?,
1345 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
1346 self.lockdown_from_offchain = true;
1347 if should_broadcast {
1348 self.broadcast_latest_local_commitment_txn(broadcaster, logger);
1350 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");
1355 self.latest_update_id = updates.update_id;
1359 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
1361 pub fn get_latest_update_id(&self) -> u64 {
1362 self.latest_update_id
1365 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
1366 pub fn get_funding_txo(&self) -> OutPoint {
1370 /// Gets a list of txids, with their output scripts (in the order they appear in the
1371 /// transaction), which we must learn about spends of via block_connected().
1372 pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<Script>> {
1373 &self.outputs_to_watch
1376 /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
1377 /// Generally useful when deserializing as during normal operation the return values of
1378 /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
1379 /// that the get_funding_txo outpoint and transaction must also be monitored for!).
1380 pub fn get_monitored_outpoints(&self) -> Vec<(Txid, u32, &Script)> {
1381 let mut res = Vec::with_capacity(self.remote_commitment_txn_on_chain.len() * 2);
1382 for (ref txid, &(_, ref outputs)) in self.remote_commitment_txn_on_chain.iter() {
1383 for (idx, output) in outputs.iter().enumerate() {
1384 res.push(((*txid).clone(), idx as u32, output));
1390 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1391 /// ChannelManager via ManyChannelMonitor::get_and_clear_pending_htlcs_updated().
1392 pub fn get_and_clear_pending_htlcs_updated(&mut self) -> Vec<HTLCUpdate> {
1393 let mut ret = Vec::new();
1394 mem::swap(&mut ret, &mut self.pending_htlcs_updated);
1398 /// Gets the list of pending events which were generated by previous actions, clearing the list
1401 /// This is called by ManyChannelMonitor::get_and_clear_pending_events() and is equivalent to
1402 /// EventsProvider::get_and_clear_pending_events() except that it requires &mut self as we do
1403 /// no internal locking in ChannelMonitors.
1404 pub fn get_and_clear_pending_events(&mut self) -> Vec<events::Event> {
1405 let mut ret = Vec::new();
1406 mem::swap(&mut ret, &mut self.pending_events);
1410 /// Can only fail if idx is < get_min_seen_secret
1411 pub(super) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
1412 self.commitment_secrets.get_secret(idx)
1415 pub(super) fn get_min_seen_secret(&self) -> u64 {
1416 self.commitment_secrets.get_min_seen_secret()
1419 pub(super) fn get_cur_remote_commitment_number(&self) -> u64 {
1420 self.current_remote_commitment_number
1423 pub(super) fn get_cur_local_commitment_number(&self) -> u64 {
1424 self.current_local_commitment_number
1427 /// Attempts to claim a remote commitment transaction's outputs using the revocation key and
1428 /// data in remote_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
1429 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
1430 /// HTLC-Success/HTLC-Timeout transactions.
1431 /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
1432 /// revoked remote commitment tx
1433 fn check_spend_remote_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) where L::Target: Logger {
1434 // Most secp and related errors trying to create keys means we have no hope of constructing
1435 // a spend transaction...so we return no transactions to broadcast
1436 let mut claimable_outpoints = Vec::new();
1437 let mut watch_outputs = Vec::new();
1439 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1440 let per_commitment_option = self.remote_claimable_outpoints.get(&commitment_txid);
1442 macro_rules! ignore_error {
1443 ( $thing : expr ) => {
1446 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs))
1451 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);
1452 if commitment_number >= self.get_min_seen_secret() {
1453 let secret = self.get_secret(commitment_number).unwrap();
1454 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1455 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1456 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.keys.pubkeys().revocation_basepoint));
1457 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));
1459 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.our_to_self_delay, &delayed_key);
1460 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1462 // First, process non-htlc outputs (to_local & to_remote)
1463 for (idx, outp) in tx.output.iter().enumerate() {
1464 if outp.script_pubkey == revokeable_p2wsh {
1465 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 };
1466 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});
1470 // Then, try to find revoked htlc outputs
1471 if let Some(ref per_commitment_data) = per_commitment_option {
1472 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1473 if let Some(transaction_output_index) = htlc.transaction_output_index {
1474 if transaction_output_index as usize >= tx.output.len() ||
1475 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1476 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1478 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()) };
1479 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable: true, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1484 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
1485 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
1486 // We're definitely a remote commitment transaction!
1487 log_trace!(logger, "Got broadcast of revoked remote commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
1488 watch_outputs.append(&mut tx.output.clone());
1489 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1491 macro_rules! check_htlc_fails {
1492 ($txid: expr, $commitment_tx: expr) => {
1493 if let Some(ref outpoints) = self.remote_claimable_outpoints.get($txid) {
1494 for &(ref htlc, ref source_option) in outpoints.iter() {
1495 if let &Some(ref source) = source_option {
1496 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), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1497 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1498 hash_map::Entry::Occupied(mut entry) => {
1499 let e = entry.get_mut();
1500 e.retain(|ref event| {
1502 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1503 return htlc_update.0 != **source
1508 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1510 hash_map::Entry::Vacant(entry) => {
1511 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1519 if let Some(ref txid) = self.current_remote_commitment_txid {
1520 check_htlc_fails!(txid, "current");
1522 if let Some(ref txid) = self.prev_remote_commitment_txid {
1523 check_htlc_fails!(txid, "remote");
1525 // No need to check local commitment txn, symmetric HTLCSource must be present as per-htlc data on remote commitment tx
1527 } else if let Some(per_commitment_data) = per_commitment_option {
1528 // While this isn't useful yet, there is a potential race where if a counterparty
1529 // revokes a state at the same time as the commitment transaction for that state is
1530 // confirmed, and the watchtower receives the block before the user, the user could
1531 // upload a new ChannelMonitor with the revocation secret but the watchtower has
1532 // already processed the block, resulting in the remote_commitment_txn_on_chain entry
1533 // not being generated by the above conditional. Thus, to be safe, we go ahead and
1535 watch_outputs.append(&mut tx.output.clone());
1536 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1538 log_trace!(logger, "Got broadcast of non-revoked remote commitment transaction {}", commitment_txid);
1540 macro_rules! check_htlc_fails {
1541 ($txid: expr, $commitment_tx: expr, $id: tt) => {
1542 if let Some(ref latest_outpoints) = self.remote_claimable_outpoints.get($txid) {
1543 $id: for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1544 if let &Some(ref source) = source_option {
1545 // Check if the HTLC is present in the commitment transaction that was
1546 // broadcast, but not if it was below the dust limit, which we should
1547 // fail backwards immediately as there is no way for us to learn the
1548 // payment_preimage.
1549 // Note that if the dust limit were allowed to change between
1550 // commitment transactions we'd want to be check whether *any*
1551 // broadcastable commitment transaction has the HTLC in it, but it
1552 // cannot currently change after channel initialization, so we don't
1554 for &(ref broadcast_htlc, ref broadcast_source) in per_commitment_data.iter() {
1555 if broadcast_htlc.transaction_output_index.is_some() && Some(source) == broadcast_source.as_ref() {
1559 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);
1560 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1561 hash_map::Entry::Occupied(mut entry) => {
1562 let e = entry.get_mut();
1563 e.retain(|ref event| {
1565 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1566 return htlc_update.0 != **source
1571 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1573 hash_map::Entry::Vacant(entry) => {
1574 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1582 if let Some(ref txid) = self.current_remote_commitment_txid {
1583 check_htlc_fails!(txid, "current", 'current_loop);
1585 if let Some(ref txid) = self.prev_remote_commitment_txid {
1586 check_htlc_fails!(txid, "previous", 'prev_loop);
1589 if let Some(revocation_points) = self.their_cur_revocation_points {
1590 let revocation_point_option =
1591 if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1592 else if let Some(point) = revocation_points.2.as_ref() {
1593 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1595 if let Some(revocation_point) = revocation_point_option {
1596 self.remote_payment_script = {
1597 // Note that the Network here is ignored as we immediately drop the address for the
1598 // script_pubkey version
1599 let payment_hash160 = WPubkeyHash::hash(&PublicKey::from_secret_key(&self.secp_ctx, &self.keys.payment_key()).serialize());
1600 Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_hash160[..]).into_script()
1603 // Then, try to find htlc outputs
1604 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1605 if let Some(transaction_output_index) = htlc.transaction_output_index {
1606 if transaction_output_index as usize >= tx.output.len() ||
1607 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1608 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1610 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
1611 let aggregable = if !htlc.offered { false } else { true };
1612 if preimage.is_some() || !htlc.offered {
1613 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() };
1614 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1621 (claimable_outpoints, (commitment_txid, watch_outputs))
1624 /// Attempts to claim a remote HTLC-Success/HTLC-Timeout's outputs using the revocation key
1625 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 {
1626 let htlc_txid = tx.txid();
1627 if tx.input.len() != 1 || tx.output.len() != 1 || tx.input[0].witness.len() != 5 {
1628 return (Vec::new(), None)
1631 macro_rules! ignore_error {
1632 ( $thing : expr ) => {
1635 Err(_) => return (Vec::new(), None)
1640 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
1641 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1642 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1644 log_trace!(logger, "Remote HTLC broadcast {}:{}", htlc_txid, 0);
1645 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 };
1646 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 });
1647 (claimable_outpoints, Some((htlc_txid, tx.output.clone())))
1650 fn broadcast_by_local_state(&self, commitment_tx: &Transaction, local_tx: &LocalSignedTx) -> (Vec<ClaimRequest>, Vec<TxOut>, Option<(Script, PublicKey, PublicKey)>) {
1651 let mut claim_requests = Vec::with_capacity(local_tx.htlc_outputs.len());
1652 let mut watch_outputs = Vec::with_capacity(local_tx.htlc_outputs.len());
1654 let redeemscript = chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.their_to_self_delay, &local_tx.delayed_payment_key);
1655 let broadcasted_local_revokable_script = Some((redeemscript.to_v0_p2wsh(), local_tx.per_commitment_point.clone(), local_tx.revocation_key.clone()));
1657 for &(ref htlc, _, _) in local_tx.htlc_outputs.iter() {
1658 if let Some(transaction_output_index) = htlc.transaction_output_index {
1659 claim_requests.push(ClaimRequest { absolute_timelock: ::std::u32::MAX, aggregable: false, outpoint: BitcoinOutPoint { txid: local_tx.txid, vout: transaction_output_index as u32 },
1660 witness_data: InputMaterial::LocalHTLC {
1661 preimage: if !htlc.offered {
1662 if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1663 Some(preimage.clone())
1665 // We can't build an HTLC-Success transaction without the preimage
1669 amount: htlc.amount_msat,
1671 watch_outputs.push(commitment_tx.output[transaction_output_index as usize].clone());
1675 (claim_requests, watch_outputs, broadcasted_local_revokable_script)
1678 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1679 /// revoked using data in local_claimable_outpoints.
1680 /// Should not be used if check_spend_revoked_transaction succeeds.
1681 fn check_spend_local_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) where L::Target: Logger {
1682 let commitment_txid = tx.txid();
1683 let mut claim_requests = Vec::new();
1684 let mut watch_outputs = Vec::new();
1686 macro_rules! wait_threshold_conf {
1687 ($height: expr, $source: expr, $commitment_tx: expr, $payment_hash: expr) => {
1688 log_trace!(logger, "Failing HTLC with payment_hash {} from {} local commitment tx due to broadcast of transaction, waiting confirmation (at height{})", log_bytes!($payment_hash.0), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1689 match self.onchain_events_waiting_threshold_conf.entry($height + ANTI_REORG_DELAY - 1) {
1690 hash_map::Entry::Occupied(mut entry) => {
1691 let e = entry.get_mut();
1692 e.retain(|ref event| {
1694 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1695 return htlc_update.0 != $source
1700 e.push(OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)});
1702 hash_map::Entry::Vacant(entry) => {
1703 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)}]);
1709 macro_rules! append_onchain_update {
1710 ($updates: expr) => {
1711 claim_requests = $updates.0;
1712 watch_outputs.append(&mut $updates.1);
1713 self.broadcasted_local_revokable_script = $updates.2;
1717 // HTLCs set may differ between last and previous local commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
1718 let mut is_local_tx = false;
1720 if self.current_local_commitment_tx.txid == commitment_txid {
1722 log_trace!(logger, "Got latest local commitment tx broadcast, searching for available HTLCs to claim");
1723 let mut res = self.broadcast_by_local_state(tx, &self.current_local_commitment_tx);
1724 append_onchain_update!(res);
1725 } else if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1726 if local_tx.txid == commitment_txid {
1728 log_trace!(logger, "Got previous local commitment tx broadcast, searching for available HTLCs to claim");
1729 let mut res = self.broadcast_by_local_state(tx, local_tx);
1730 append_onchain_update!(res);
1734 macro_rules! fail_dust_htlcs_after_threshold_conf {
1735 ($local_tx: expr) => {
1736 for &(ref htlc, _, ref source) in &$local_tx.htlc_outputs {
1737 if htlc.transaction_output_index.is_none() {
1738 if let &Some(ref source) = source {
1739 wait_threshold_conf!(height, source.clone(), "lastest", htlc.payment_hash.clone());
1747 fail_dust_htlcs_after_threshold_conf!(self.current_local_commitment_tx);
1748 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1749 fail_dust_htlcs_after_threshold_conf!(local_tx);
1753 (claim_requests, (commitment_txid, watch_outputs))
1756 /// Used by ChannelManager deserialization to broadcast the latest local state if its copy of
1757 /// the Channel was out-of-date. You may use it to get a broadcastable local toxic tx in case of
1758 /// fallen-behind, i.e when receiving a channel_reestablish with a proof that our remote side knows
1759 /// a higher revocation secret than the local commitment number we are aware of. Broadcasting these
1760 /// transactions are UNSAFE, as they allow remote side to punish you. Nevertheless you may want to
1761 /// broadcast them if remote don't close channel with his higher commitment transaction after a
1762 /// substantial amount of time (a month or even a year) to get back funds. Best may be to contact
1763 /// out-of-band the other node operator to coordinate with him if option is available to you.
1764 /// In any-case, choice is up to the user.
1765 pub fn get_latest_local_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1766 log_trace!(logger, "Getting signed latest local commitment transaction!");
1767 self.local_tx_signed = true;
1768 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_local_tx(&self.funding_redeemscript) {
1769 let txid = commitment_tx.txid();
1770 let mut res = vec![commitment_tx];
1771 for htlc in self.current_local_commitment_tx.htlc_outputs.iter() {
1772 if let Some(vout) = htlc.0.transaction_output_index {
1773 let preimage = if !htlc.0.offered {
1774 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1775 // We can't build an HTLC-Success transaction without the preimage
1779 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
1780 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1785 // 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.
1786 // The data will be re-generated and tracked in check_spend_local_transaction if we get a confirmation.
1792 /// Unsafe test-only version of get_latest_local_commitment_txn used by our test framework
1793 /// to bypass LocalCommitmentTransaction state update lockdown after signature and generate
1794 /// revoked commitment transaction.
1796 pub fn unsafe_get_latest_local_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
1797 log_trace!(logger, "Getting signed copy of latest local commitment transaction!");
1798 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_copy_local_tx(&self.funding_redeemscript) {
1799 let txid = commitment_tx.txid();
1800 let mut res = vec![commitment_tx];
1801 for htlc in self.current_local_commitment_tx.htlc_outputs.iter() {
1802 if let Some(vout) = htlc.0.transaction_output_index {
1803 let preimage = if !htlc.0.offered {
1804 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1805 // We can't build an HTLC-Success transaction without the preimage
1809 if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
1810 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1820 /// Called by SimpleManyChannelMonitor::block_connected, which implements
1821 /// ChainListener::block_connected.
1822 /// Eventually this should be pub and, roughly, implement ChainListener, however this requires
1823 /// &mut self, as well as returns new spendable outputs and outpoints to watch for spending of
1825 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>)>
1826 where B::Target: BroadcasterInterface,
1827 F::Target: FeeEstimator,
1830 for tx in txn_matched {
1831 let mut output_val = 0;
1832 for out in tx.output.iter() {
1833 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1834 output_val += out.value;
1835 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1839 log_trace!(logger, "Block {} at height {} connected with {} txn matched", block_hash, height, txn_matched.len());
1840 let mut watch_outputs = Vec::new();
1841 let mut claimable_outpoints = Vec::new();
1842 for tx in txn_matched {
1843 if tx.input.len() == 1 {
1844 // Assuming our keys were not leaked (in which case we're screwed no matter what),
1845 // commitment transactions and HTLC transactions will all only ever have one input,
1846 // which is an easy way to filter out any potential non-matching txn for lazy
1848 let prevout = &tx.input[0].previous_output;
1849 if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
1850 if (tx.input[0].sequence >> 8*3) as u8 == 0x80 && (tx.lock_time >> 8*3) as u8 == 0x20 {
1851 let (mut new_outpoints, new_outputs) = self.check_spend_remote_transaction(&tx, height, &logger);
1852 if !new_outputs.1.is_empty() {
1853 watch_outputs.push(new_outputs);
1855 if new_outpoints.is_empty() {
1856 let (mut new_outpoints, new_outputs) = self.check_spend_local_transaction(&tx, height, &logger);
1857 if !new_outputs.1.is_empty() {
1858 watch_outputs.push(new_outputs);
1860 claimable_outpoints.append(&mut new_outpoints);
1862 claimable_outpoints.append(&mut new_outpoints);
1865 if let Some(&(commitment_number, _)) = self.remote_commitment_txn_on_chain.get(&prevout.txid) {
1866 let (mut new_outpoints, new_outputs_option) = self.check_spend_remote_htlc(&tx, commitment_number, height, &logger);
1867 claimable_outpoints.append(&mut new_outpoints);
1868 if let Some(new_outputs) = new_outputs_option {
1869 watch_outputs.push(new_outputs);
1874 // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
1875 // can also be resolved in a few other ways which can have more than one output. Thus,
1876 // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
1877 self.is_resolving_htlc_output(&tx, height, &logger);
1879 self.is_paying_spendable_output(&tx, height, &logger);
1881 let should_broadcast = self.would_broadcast_at_height(height, &logger);
1882 if should_broadcast {
1883 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() }});
1885 if should_broadcast {
1886 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_local_tx(&self.funding_redeemscript) {
1887 let (mut new_outpoints, new_outputs, _) = self.broadcast_by_local_state(&commitment_tx, &self.current_local_commitment_tx);
1888 if !new_outputs.is_empty() {
1889 watch_outputs.push((self.current_local_commitment_tx.txid.clone(), new_outputs));
1891 claimable_outpoints.append(&mut new_outpoints);
1894 if let Some(events) = self.onchain_events_waiting_threshold_conf.remove(&height) {
1897 OnchainEvent::HTLCUpdate { htlc_update } => {
1898 log_trace!(logger, "HTLC {} failure update has got enough confirmations to be passed upstream", log_bytes!((htlc_update.1).0));
1899 self.pending_htlcs_updated.push(HTLCUpdate {
1900 payment_hash: htlc_update.1,
1901 payment_preimage: None,
1902 source: htlc_update.0,
1905 OnchainEvent::MaturingOutput { descriptor } => {
1906 log_trace!(logger, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
1907 self.pending_events.push(events::Event::SpendableOutputs {
1908 outputs: vec![descriptor]
1914 self.onchain_tx_handler.block_connected(txn_matched, claimable_outpoints, height, &*broadcaster, &*fee_estimator, &*logger);
1916 self.last_block_hash = block_hash.clone();
1917 for &(ref txid, ref output_scripts) in watch_outputs.iter() {
1918 self.outputs_to_watch.insert(txid.clone(), output_scripts.iter().map(|o| o.script_pubkey.clone()).collect());
1924 fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, height: u32, block_hash: &BlockHash, broadcaster: B, fee_estimator: F, logger: L)
1925 where B::Target: BroadcasterInterface,
1926 F::Target: FeeEstimator,
1929 log_trace!(logger, "Block {} at height {} disconnected", block_hash, height);
1930 if let Some(_) = self.onchain_events_waiting_threshold_conf.remove(&(height + ANTI_REORG_DELAY - 1)) {
1932 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
1933 //- maturing spendable output has transaction paying us has been disconnected
1936 self.onchain_tx_handler.block_disconnected(height, broadcaster, fee_estimator, logger);
1938 self.last_block_hash = block_hash.clone();
1941 pub(super) fn would_broadcast_at_height<L: Deref>(&self, height: u32, logger: &L) -> bool where L::Target: Logger {
1942 // We need to consider all HTLCs which are:
1943 // * in any unrevoked remote commitment transaction, as they could broadcast said
1944 // transactions and we'd end up in a race, or
1945 // * are in our latest local commitment transaction, as this is the thing we will
1946 // broadcast if we go on-chain.
1947 // Note that we consider HTLCs which were below dust threshold here - while they don't
1948 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
1949 // to the source, and if we don't fail the channel we will have to ensure that the next
1950 // updates that peer sends us are update_fails, failing the channel if not. It's probably
1951 // easier to just fail the channel as this case should be rare enough anyway.
1952 macro_rules! scan_commitment {
1953 ($htlcs: expr, $local_tx: expr) => {
1954 for ref htlc in $htlcs {
1955 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
1956 // chain with enough room to claim the HTLC without our counterparty being able to
1957 // time out the HTLC first.
1958 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
1959 // concern is being able to claim the corresponding inbound HTLC (on another
1960 // channel) before it expires. In fact, we don't even really care if our
1961 // counterparty here claims such an outbound HTLC after it expired as long as we
1962 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
1963 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
1964 // we give ourselves a few blocks of headroom after expiration before going
1965 // on-chain for an expired HTLC.
1966 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
1967 // from us until we've reached the point where we go on-chain with the
1968 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
1969 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
1970 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
1971 // inbound_cltv == height + CLTV_CLAIM_BUFFER
1972 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
1973 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
1974 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
1975 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
1976 // The final, above, condition is checked for statically in channelmanager
1977 // with CHECK_CLTV_EXPIRY_SANITY_2.
1978 let htlc_outbound = $local_tx == htlc.offered;
1979 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
1980 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
1981 log_info!(logger, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
1988 scan_commitment!(self.current_local_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
1990 if let Some(ref txid) = self.current_remote_commitment_txid {
1991 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(txid) {
1992 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
1995 if let Some(ref txid) = self.prev_remote_commitment_txid {
1996 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(txid) {
1997 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2004 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a local
2005 /// or remote commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
2006 fn is_resolving_htlc_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2007 'outer_loop: for input in &tx.input {
2008 let mut payment_data = None;
2009 let revocation_sig_claim = (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && input.witness[1].len() == 33)
2010 || (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && input.witness[1].len() == 33);
2011 let accepted_preimage_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::AcceptedHTLC);
2012 let offered_preimage_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC);
2014 macro_rules! log_claim {
2015 ($tx_info: expr, $local_tx: expr, $htlc: expr, $source_avail: expr) => {
2016 // We found the output in question, but aren't failing it backwards
2017 // as we have no corresponding source and no valid remote commitment txid
2018 // to try a weak source binding with same-hash, same-value still-valid offered HTLC.
2019 // This implies either it is an inbound HTLC or an outbound HTLC on a revoked transaction.
2020 let outbound_htlc = $local_tx == $htlc.offered;
2021 if ($local_tx && revocation_sig_claim) ||
2022 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
2023 log_error!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
2024 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2025 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2026 if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back" });
2028 log_info!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
2029 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2030 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2031 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
2036 macro_rules! check_htlc_valid_remote {
2037 ($remote_txid: expr, $htlc_output: expr) => {
2038 if let Some(txid) = $remote_txid {
2039 for &(ref pending_htlc, ref pending_source) in self.remote_claimable_outpoints.get(&txid).unwrap() {
2040 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
2041 if let &Some(ref source) = pending_source {
2042 log_claim!("revoked remote commitment tx", false, pending_htlc, true);
2043 payment_data = Some(((**source).clone(), $htlc_output.payment_hash));
2052 macro_rules! scan_commitment {
2053 ($htlcs: expr, $tx_info: expr, $local_tx: expr) => {
2054 for (ref htlc_output, source_option) in $htlcs {
2055 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
2056 if let Some(ref source) = source_option {
2057 log_claim!($tx_info, $local_tx, htlc_output, true);
2058 // We have a resolution of an HTLC either from one of our latest
2059 // local commitment transactions or an unrevoked remote commitment
2060 // transaction. This implies we either learned a preimage, the HTLC
2061 // has timed out, or we screwed up. In any case, we should now
2062 // resolve the source HTLC with the original sender.
2063 payment_data = Some(((*source).clone(), htlc_output.payment_hash));
2064 } else if !$local_tx {
2065 check_htlc_valid_remote!(self.current_remote_commitment_txid, htlc_output);
2066 if payment_data.is_none() {
2067 check_htlc_valid_remote!(self.prev_remote_commitment_txid, htlc_output);
2070 if payment_data.is_none() {
2071 log_claim!($tx_info, $local_tx, htlc_output, false);
2072 continue 'outer_loop;
2079 if input.previous_output.txid == self.current_local_commitment_tx.txid {
2080 scan_commitment!(self.current_local_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2081 "our latest local commitment tx", true);
2083 if let Some(ref prev_local_signed_commitment_tx) = self.prev_local_signed_commitment_tx {
2084 if input.previous_output.txid == prev_local_signed_commitment_tx.txid {
2085 scan_commitment!(prev_local_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2086 "our previous local commitment tx", true);
2089 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(&input.previous_output.txid) {
2090 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
2091 "remote commitment tx", false);
2094 // Check that scan_commitment, above, decided there is some source worth relaying an
2095 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
2096 if let Some((source, payment_hash)) = payment_data {
2097 let mut payment_preimage = PaymentPreimage([0; 32]);
2098 if accepted_preimage_claim {
2099 if !self.pending_htlcs_updated.iter().any(|update| update.source == source) {
2100 payment_preimage.0.copy_from_slice(&input.witness[3]);
2101 self.pending_htlcs_updated.push(HTLCUpdate {
2103 payment_preimage: Some(payment_preimage),
2107 } else if offered_preimage_claim {
2108 if !self.pending_htlcs_updated.iter().any(|update| update.source == source) {
2109 payment_preimage.0.copy_from_slice(&input.witness[1]);
2110 self.pending_htlcs_updated.push(HTLCUpdate {
2112 payment_preimage: Some(payment_preimage),
2117 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);
2118 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2119 hash_map::Entry::Occupied(mut entry) => {
2120 let e = entry.get_mut();
2121 e.retain(|ref event| {
2123 OnchainEvent::HTLCUpdate { ref htlc_update } => {
2124 return htlc_update.0 != source
2129 e.push(OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)});
2131 hash_map::Entry::Vacant(entry) => {
2132 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)}]);
2140 /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
2141 fn is_paying_spendable_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2142 let mut spendable_output = None;
2143 for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
2144 if outp.script_pubkey == self.destination_script {
2145 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2146 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2147 output: outp.clone(),
2150 } else if let Some(ref broadcasted_local_revokable_script) = self.broadcasted_local_revokable_script {
2151 if broadcasted_local_revokable_script.0 == outp.script_pubkey {
2152 spendable_output = Some(SpendableOutputDescriptor::DynamicOutputP2WSH {
2153 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2154 per_commitment_point: broadcasted_local_revokable_script.1,
2155 to_self_delay: self.their_to_self_delay,
2156 output: outp.clone(),
2157 key_derivation_params: self.keys.key_derivation_params(),
2158 remote_revocation_pubkey: broadcasted_local_revokable_script.2.clone(),
2162 } else if self.remote_payment_script == outp.script_pubkey {
2163 spendable_output = Some(SpendableOutputDescriptor::DynamicOutputP2WPKH {
2164 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2165 output: outp.clone(),
2166 key_derivation_params: self.keys.key_derivation_params(),
2169 } else if outp.script_pubkey == self.shutdown_script {
2170 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2171 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2172 output: outp.clone(),
2176 if let Some(spendable_output) = spendable_output {
2177 log_trace!(logger, "Maturing {} until {}", log_spendable!(spendable_output), height + ANTI_REORG_DELAY - 1);
2178 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2179 hash_map::Entry::Occupied(mut entry) => {
2180 let e = entry.get_mut();
2181 e.push(OnchainEvent::MaturingOutput { descriptor: spendable_output });
2183 hash_map::Entry::Vacant(entry) => {
2184 entry.insert(vec![OnchainEvent::MaturingOutput { descriptor: spendable_output }]);
2191 const MAX_ALLOC_SIZE: usize = 64*1024;
2193 impl<ChanSigner: ChannelKeys + Readable> Readable for (BlockHash, ChannelMonitor<ChanSigner>) {
2194 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
2195 macro_rules! unwrap_obj {
2199 Err(_) => return Err(DecodeError::InvalidValue),
2204 let _ver: u8 = Readable::read(reader)?;
2205 let min_ver: u8 = Readable::read(reader)?;
2206 if min_ver > SERIALIZATION_VERSION {
2207 return Err(DecodeError::UnknownVersion);
2210 let latest_update_id: u64 = Readable::read(reader)?;
2211 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
2213 let destination_script = Readable::read(reader)?;
2214 let broadcasted_local_revokable_script = match <u8 as Readable>::read(reader)? {
2216 let revokable_address = Readable::read(reader)?;
2217 let per_commitment_point = Readable::read(reader)?;
2218 let revokable_script = Readable::read(reader)?;
2219 Some((revokable_address, per_commitment_point, revokable_script))
2222 _ => return Err(DecodeError::InvalidValue),
2224 let remote_payment_script = Readable::read(reader)?;
2225 let shutdown_script = Readable::read(reader)?;
2227 let keys = Readable::read(reader)?;
2228 // Technically this can fail and serialize fail a round-trip, but only for serialization of
2229 // barely-init'd ChannelMonitors that we can't do anything with.
2230 let outpoint = OutPoint {
2231 txid: Readable::read(reader)?,
2232 index: Readable::read(reader)?,
2234 let funding_info = (outpoint, Readable::read(reader)?);
2235 let current_remote_commitment_txid = Readable::read(reader)?;
2236 let prev_remote_commitment_txid = Readable::read(reader)?;
2238 let remote_tx_cache = {
2239 let remote_delayed_payment_base_key = Readable::read(reader)?;
2240 let remote_htlc_base_key = Readable::read(reader)?;
2241 let per_htlc_len: u64 = Readable::read(reader)?;
2242 let mut per_htlc = HashMap::with_capacity(cmp::min(per_htlc_len as usize, MAX_ALLOC_SIZE / 64));
2243 for _ in 0..per_htlc_len {
2244 let txid: Txid = Readable::read(reader)?;
2245 let htlcs_count: u64 = Readable::read(reader)?;
2246 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
2247 for _ in 0..htlcs_count {
2248 let htlc = Readable::read(reader)?;
2251 if let Some(_) = per_htlc.insert(txid, htlcs) {
2252 return Err(DecodeError::InvalidValue);
2256 remote_delayed_payment_base_key,
2257 remote_htlc_base_key,
2261 let funding_redeemscript = Readable::read(reader)?;
2262 let channel_value_satoshis = Readable::read(reader)?;
2264 let their_cur_revocation_points = {
2265 let first_idx = <U48 as Readable>::read(reader)?.0;
2269 let first_point = Readable::read(reader)?;
2270 let second_point_slice: [u8; 33] = Readable::read(reader)?;
2271 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
2272 Some((first_idx, first_point, None))
2274 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
2279 let our_to_self_delay: u16 = Readable::read(reader)?;
2280 let their_to_self_delay: u16 = Readable::read(reader)?;
2282 let commitment_secrets = Readable::read(reader)?;
2284 macro_rules! read_htlc_in_commitment {
2287 let offered: bool = Readable::read(reader)?;
2288 let amount_msat: u64 = Readable::read(reader)?;
2289 let cltv_expiry: u32 = Readable::read(reader)?;
2290 let payment_hash: PaymentHash = Readable::read(reader)?;
2291 let transaction_output_index: Option<u32> = Readable::read(reader)?;
2293 HTLCOutputInCommitment {
2294 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
2300 let remote_claimable_outpoints_len: u64 = Readable::read(reader)?;
2301 let mut remote_claimable_outpoints = HashMap::with_capacity(cmp::min(remote_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
2302 for _ in 0..remote_claimable_outpoints_len {
2303 let txid: Txid = Readable::read(reader)?;
2304 let htlcs_count: u64 = Readable::read(reader)?;
2305 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
2306 for _ in 0..htlcs_count {
2307 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
2309 if let Some(_) = remote_claimable_outpoints.insert(txid, htlcs) {
2310 return Err(DecodeError::InvalidValue);
2314 let remote_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
2315 let mut remote_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(remote_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
2316 for _ in 0..remote_commitment_txn_on_chain_len {
2317 let txid: Txid = Readable::read(reader)?;
2318 let commitment_number = <U48 as Readable>::read(reader)?.0;
2319 let outputs_count = <u64 as Readable>::read(reader)?;
2320 let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 8));
2321 for _ in 0..outputs_count {
2322 outputs.push(Readable::read(reader)?);
2324 if let Some(_) = remote_commitment_txn_on_chain.insert(txid, (commitment_number, outputs)) {
2325 return Err(DecodeError::InvalidValue);
2329 let remote_hash_commitment_number_len: u64 = Readable::read(reader)?;
2330 let mut remote_hash_commitment_number = HashMap::with_capacity(cmp::min(remote_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
2331 for _ in 0..remote_hash_commitment_number_len {
2332 let payment_hash: PaymentHash = Readable::read(reader)?;
2333 let commitment_number = <U48 as Readable>::read(reader)?.0;
2334 if let Some(_) = remote_hash_commitment_number.insert(payment_hash, commitment_number) {
2335 return Err(DecodeError::InvalidValue);
2339 macro_rules! read_local_tx {
2342 let txid = Readable::read(reader)?;
2343 let revocation_key = Readable::read(reader)?;
2344 let a_htlc_key = Readable::read(reader)?;
2345 let b_htlc_key = Readable::read(reader)?;
2346 let delayed_payment_key = Readable::read(reader)?;
2347 let per_commitment_point = Readable::read(reader)?;
2348 let feerate_per_kw: u64 = Readable::read(reader)?;
2350 let htlcs_len: u64 = Readable::read(reader)?;
2351 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_len as usize, MAX_ALLOC_SIZE / 128));
2352 for _ in 0..htlcs_len {
2353 let htlc = read_htlc_in_commitment!();
2354 let sigs = match <u8 as Readable>::read(reader)? {
2356 1 => Some(Readable::read(reader)?),
2357 _ => return Err(DecodeError::InvalidValue),
2359 htlcs.push((htlc, sigs, Readable::read(reader)?));
2364 revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, per_commitment_point, feerate_per_kw,
2371 let prev_local_signed_commitment_tx = match <u8 as Readable>::read(reader)? {
2374 Some(read_local_tx!())
2376 _ => return Err(DecodeError::InvalidValue),
2378 let current_local_commitment_tx = read_local_tx!();
2380 let current_remote_commitment_number = <U48 as Readable>::read(reader)?.0;
2381 let current_local_commitment_number = <U48 as Readable>::read(reader)?.0;
2383 let payment_preimages_len: u64 = Readable::read(reader)?;
2384 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
2385 for _ in 0..payment_preimages_len {
2386 let preimage: PaymentPreimage = Readable::read(reader)?;
2387 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2388 if let Some(_) = payment_preimages.insert(hash, preimage) {
2389 return Err(DecodeError::InvalidValue);
2393 let pending_htlcs_updated_len: u64 = Readable::read(reader)?;
2394 let mut pending_htlcs_updated = Vec::with_capacity(cmp::min(pending_htlcs_updated_len as usize, MAX_ALLOC_SIZE / (32 + 8*3)));
2395 for _ in 0..pending_htlcs_updated_len {
2396 pending_htlcs_updated.push(Readable::read(reader)?);
2399 let pending_events_len: u64 = Readable::read(reader)?;
2400 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<events::Event>()));
2401 for _ in 0..pending_events_len {
2402 if let Some(event) = MaybeReadable::read(reader)? {
2403 pending_events.push(event);
2407 let last_block_hash: BlockHash = Readable::read(reader)?;
2409 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
2410 let mut onchain_events_waiting_threshold_conf = HashMap::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
2411 for _ in 0..waiting_threshold_conf_len {
2412 let height_target = Readable::read(reader)?;
2413 let events_len: u64 = Readable::read(reader)?;
2414 let mut events = Vec::with_capacity(cmp::min(events_len as usize, MAX_ALLOC_SIZE / 128));
2415 for _ in 0..events_len {
2416 let ev = match <u8 as Readable>::read(reader)? {
2418 let htlc_source = Readable::read(reader)?;
2419 let hash = Readable::read(reader)?;
2420 OnchainEvent::HTLCUpdate {
2421 htlc_update: (htlc_source, hash)
2425 let descriptor = Readable::read(reader)?;
2426 OnchainEvent::MaturingOutput {
2430 _ => return Err(DecodeError::InvalidValue),
2434 onchain_events_waiting_threshold_conf.insert(height_target, events);
2437 let outputs_to_watch_len: u64 = Readable::read(reader)?;
2438 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>>())));
2439 for _ in 0..outputs_to_watch_len {
2440 let txid = Readable::read(reader)?;
2441 let outputs_len: u64 = Readable::read(reader)?;
2442 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Script>()));
2443 for _ in 0..outputs_len {
2444 outputs.push(Readable::read(reader)?);
2446 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
2447 return Err(DecodeError::InvalidValue);
2450 let onchain_tx_handler = Readable::read(reader)?;
2452 let lockdown_from_offchain = Readable::read(reader)?;
2453 let local_tx_signed = Readable::read(reader)?;
2455 Ok((last_block_hash.clone(), ChannelMonitor {
2457 commitment_transaction_number_obscure_factor,
2460 broadcasted_local_revokable_script,
2461 remote_payment_script,
2466 current_remote_commitment_txid,
2467 prev_remote_commitment_txid,
2470 funding_redeemscript,
2471 channel_value_satoshis,
2472 their_cur_revocation_points,
2475 their_to_self_delay,
2478 remote_claimable_outpoints,
2479 remote_commitment_txn_on_chain,
2480 remote_hash_commitment_number,
2482 prev_local_signed_commitment_tx,
2483 current_local_commitment_tx,
2484 current_remote_commitment_number,
2485 current_local_commitment_number,
2488 pending_htlcs_updated,
2491 onchain_events_waiting_threshold_conf,
2496 lockdown_from_offchain,
2500 secp_ctx: Secp256k1::new(),
2507 use bitcoin::blockdata::script::{Script, Builder};
2508 use bitcoin::blockdata::opcodes;
2509 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, SigHashType};
2510 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
2511 use bitcoin::util::bip143;
2512 use bitcoin::hashes::Hash;
2513 use bitcoin::hashes::sha256::Hash as Sha256;
2514 use bitcoin::hashes::hex::FromHex;
2515 use bitcoin::hash_types::Txid;
2517 use chain::transaction::OutPoint;
2518 use ln::channelmanager::{PaymentPreimage, PaymentHash};
2519 use ln::channelmonitor::ChannelMonitor;
2520 use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
2522 use ln::chan_utils::{HTLCOutputInCommitment, LocalCommitmentTransaction};
2523 use util::test_utils::TestLogger;
2524 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
2525 use bitcoin::secp256k1::Secp256k1;
2526 use rand::{thread_rng,Rng};
2528 use chain::keysinterface::InMemoryChannelKeys;
2531 fn test_prune_preimages() {
2532 let secp_ctx = Secp256k1::new();
2533 let logger = Arc::new(TestLogger::new());
2535 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
2536 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2538 let mut preimages = Vec::new();
2540 let mut rng = thread_rng();
2542 let mut preimage = PaymentPreimage([0; 32]);
2543 rng.fill_bytes(&mut preimage.0[..]);
2544 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2545 preimages.push((preimage, hash));
2549 macro_rules! preimages_slice_to_htlc_outputs {
2550 ($preimages_slice: expr) => {
2552 let mut res = Vec::new();
2553 for (idx, preimage) in $preimages_slice.iter().enumerate() {
2554 res.push((HTLCOutputInCommitment {
2558 payment_hash: preimage.1.clone(),
2559 transaction_output_index: Some(idx as u32),
2566 macro_rules! preimages_to_local_htlcs {
2567 ($preimages_slice: expr) => {
2569 let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2570 let res: Vec<_> = inp.drain(..).map(|e| { (e.0, None, e.1) }).collect();
2576 macro_rules! test_preimages_exist {
2577 ($preimages_slice: expr, $monitor: expr) => {
2578 for preimage in $preimages_slice {
2579 assert!($monitor.payment_preimages.contains_key(&preimage.1));
2584 let keys = InMemoryChannelKeys::new(
2586 SecretKey::from_slice(&[41; 32]).unwrap(),
2587 SecretKey::from_slice(&[41; 32]).unwrap(),
2588 SecretKey::from_slice(&[41; 32]).unwrap(),
2589 SecretKey::from_slice(&[41; 32]).unwrap(),
2590 SecretKey::from_slice(&[41; 32]).unwrap(),
2596 // Prune with one old state and a local commitment tx holding a few overlaps with the
2598 let mut monitor = ChannelMonitor::new(keys,
2599 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()), 0, &Script::new(),
2600 (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
2601 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
2602 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
2603 10, Script::new(), 46, 0, LocalCommitmentTransaction::dummy());
2605 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..10])).unwrap();
2606 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
2607 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
2608 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
2609 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
2610 for &(ref preimage, ref hash) in preimages.iter() {
2611 monitor.provide_payment_preimage(hash, preimage);
2614 // Now provide a secret, pruning preimages 10-15
2615 let mut secret = [0; 32];
2616 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2617 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2618 assert_eq!(monitor.payment_preimages.len(), 15);
2619 test_preimages_exist!(&preimages[0..10], monitor);
2620 test_preimages_exist!(&preimages[15..20], monitor);
2622 // Now provide a further secret, pruning preimages 15-17
2623 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2624 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2625 assert_eq!(monitor.payment_preimages.len(), 13);
2626 test_preimages_exist!(&preimages[0..10], monitor);
2627 test_preimages_exist!(&preimages[17..20], monitor);
2629 // Now update local commitment tx info, pruning only element 18 as we still care about the
2630 // previous commitment tx's preimages too
2631 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..5])).unwrap();
2632 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2633 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2634 assert_eq!(monitor.payment_preimages.len(), 12);
2635 test_preimages_exist!(&preimages[0..10], monitor);
2636 test_preimages_exist!(&preimages[18..20], monitor);
2638 // But if we do it again, we'll prune 5-10
2639 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..3])).unwrap();
2640 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2641 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2642 assert_eq!(monitor.payment_preimages.len(), 5);
2643 test_preimages_exist!(&preimages[0..5], monitor);
2647 fn test_claim_txn_weight_computation() {
2648 // We test Claim txn weight, knowing that we want expected weigth and
2649 // not actual case to avoid sigs and time-lock delays hell variances.
2651 let secp_ctx = Secp256k1::new();
2652 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
2653 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
2654 let mut sum_actual_sigs = 0;
2656 macro_rules! sign_input {
2657 ($sighash_parts: expr, $input: expr, $idx: expr, $amount: expr, $input_type: expr, $sum_actual_sigs: expr) => {
2658 let htlc = HTLCOutputInCommitment {
2659 offered: if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::OfferedHTLC { true } else { false },
2661 cltv_expiry: 2 << 16,
2662 payment_hash: PaymentHash([1; 32]),
2663 transaction_output_index: Some($idx),
2665 let redeem_script = if *$input_type == InputDescriptors::RevokedOutput { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &pubkey, &pubkey, &pubkey) };
2666 let sighash = hash_to_message!(&$sighash_parts.sighash_all(&$input, &redeem_script, $amount)[..]);
2667 let sig = secp_ctx.sign(&sighash, &privkey);
2668 $input.witness.push(sig.serialize_der().to_vec());
2669 $input.witness[0].push(SigHashType::All as u8);
2670 sum_actual_sigs += $input.witness[0].len();
2671 if *$input_type == InputDescriptors::RevokedOutput {
2672 $input.witness.push(vec!(1));
2673 } else if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::RevokedReceivedHTLC {
2674 $input.witness.push(pubkey.clone().serialize().to_vec());
2675 } else if *$input_type == InputDescriptors::ReceivedHTLC {
2676 $input.witness.push(vec![0]);
2678 $input.witness.push(PaymentPreimage([1; 32]).0.to_vec());
2680 $input.witness.push(redeem_script.into_bytes());
2681 println!("witness[0] {}", $input.witness[0].len());
2682 println!("witness[1] {}", $input.witness[1].len());
2683 println!("witness[2] {}", $input.witness[2].len());
2687 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
2688 let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
2690 // Justice tx with 1 to_local, 2 revoked offered HTLCs, 1 revoked received HTLCs
2691 let mut claim_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2693 claim_tx.input.push(TxIn {
2694 previous_output: BitcoinOutPoint {
2698 script_sig: Script::new(),
2699 sequence: 0xfffffffd,
2700 witness: Vec::new(),
2703 claim_tx.output.push(TxOut {
2704 script_pubkey: script_pubkey.clone(),
2707 let base_weight = claim_tx.get_weight();
2708 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2709 let inputs_des = vec![InputDescriptors::RevokedOutput, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedReceivedHTLC];
2710 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2711 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2713 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));
2715 // Claim tx with 1 offered HTLCs, 3 received HTLCs
2716 claim_tx.input.clear();
2717 sum_actual_sigs = 0;
2719 claim_tx.input.push(TxIn {
2720 previous_output: BitcoinOutPoint {
2724 script_sig: Script::new(),
2725 sequence: 0xfffffffd,
2726 witness: Vec::new(),
2729 let base_weight = claim_tx.get_weight();
2730 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2731 let inputs_des = vec![InputDescriptors::OfferedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC];
2732 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2733 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2735 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));
2737 // Justice tx with 1 revoked HTLC-Success tx output
2738 claim_tx.input.clear();
2739 sum_actual_sigs = 0;
2740 claim_tx.input.push(TxIn {
2741 previous_output: BitcoinOutPoint {
2745 script_sig: Script::new(),
2746 sequence: 0xfffffffd,
2747 witness: Vec::new(),
2749 let base_weight = claim_tx.get_weight();
2750 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2751 let inputs_des = vec![InputDescriptors::RevokedOutput];
2752 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2753 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2755 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));
2758 // Further testing is done in the ChannelManager integration tests.