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 latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date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_hashes::hash160::Hash as Hash160;
25 use bitcoin_hashes::sha256d::Hash as Sha256dHash;
27 use secp256k1::{Secp256k1,Signature};
28 use secp256k1::key::{SecretKey,PublicKey};
31 use ln::msgs::DecodeError;
33 use ln::chan_utils::{CounterpartyCommitmentSecrets, HTLCOutputInCommitment, LocalCommitmentTransaction, HTLCType};
34 use ln::channelmanager::{HTLCSource, PaymentPreimage, PaymentHash};
35 use ln::onchaintx::OnchainTxHandler;
36 use chain::chaininterface::{ChainListener, ChainWatchInterface, BroadcasterInterface, FeeEstimator};
37 use chain::transaction::OutPoint;
38 use chain::keysinterface::{SpendableOutputDescriptor, ChannelKeys};
39 use util::logger::Logger;
40 use util::ser::{ReadableArgs, Readable, MaybeReadable, Writer, Writeable, U48};
41 use util::{byte_utils, events};
43 use std::collections::{HashMap, hash_map};
44 use std::sync::{Arc,Mutex};
45 use std::{hash,cmp, mem};
48 /// An update generated by the underlying Channel itself which contains some new information the
49 /// ChannelMonitor should be made aware of.
50 #[cfg_attr(test, derive(PartialEq))]
53 pub struct ChannelMonitorUpdate {
54 pub(super) updates: Vec<ChannelMonitorUpdateStep>,
55 /// The sequence number of this update. Updates *must* be replayed in-order according to this
56 /// sequence number (and updates may panic if they are not). The update_id values are strictly
57 /// increasing and increase by one for each new update.
59 /// This sequence number is also used to track up to which points updates which returned
60 /// ChannelMonitorUpdateErr::TemporaryFailure have been applied to all copies of a given
61 /// ChannelMonitor when ChannelManager::channel_monitor_updated is called.
65 impl Writeable for ChannelMonitorUpdate {
66 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
67 self.update_id.write(w)?;
68 (self.updates.len() as u64).write(w)?;
69 for update_step in self.updates.iter() {
70 update_step.write(w)?;
75 impl Readable for ChannelMonitorUpdate {
76 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
77 let update_id: u64 = Readable::read(r)?;
78 let len: u64 = Readable::read(r)?;
79 let mut updates = Vec::with_capacity(cmp::min(len as usize, MAX_ALLOC_SIZE / ::std::mem::size_of::<ChannelMonitorUpdateStep>()));
81 updates.push(Readable::read(r)?);
83 Ok(Self { update_id, updates })
87 /// An error enum representing a failure to persist a channel monitor update.
89 pub enum ChannelMonitorUpdateErr {
90 /// Used to indicate a temporary failure (eg connection to a watchtower or remote backup of
91 /// our state failed, but is expected to succeed at some point in the future).
93 /// Such a failure will "freeze" a channel, preventing us from revoking old states or
94 /// submitting new commitment transactions to the remote party. Once the update(s) which failed
95 /// have been successfully applied, ChannelManager::channel_monitor_updated can be used to
96 /// restore the channel to an operational state.
98 /// Note that a given ChannelManager will *never* re-generate a given ChannelMonitorUpdate. If
99 /// you return a TemporaryFailure you must ensure that it is written to disk safely before
100 /// writing out the latest ChannelManager state.
102 /// Even when a channel has been "frozen" updates to the ChannelMonitor can continue to occur
103 /// (eg if an inbound HTLC which we forwarded was claimed upstream resulting in us attempting
104 /// to claim it on this channel) and those updates must be applied wherever they can be. At
105 /// least one such updated ChannelMonitor must be persisted otherwise PermanentFailure should
106 /// be returned to get things on-chain ASAP using only the in-memory copy. Obviously updates to
107 /// the channel which would invalidate previous ChannelMonitors are not made when a channel has
110 /// Note that even if updates made after TemporaryFailure succeed you must still call
111 /// channel_monitor_updated to ensure you have the latest monitor and re-enable normal channel
114 /// Note that the update being processed here will not be replayed for you when you call
115 /// ChannelManager::channel_monitor_updated, so you must store the update itself along
116 /// with the persisted ChannelMonitor on your own local disk prior to returning a
117 /// TemporaryFailure. You may, of course, employ a journaling approach, storing only the
118 /// ChannelMonitorUpdate on disk without updating the monitor itself, replaying the journal at
121 /// For deployments where a copy of ChannelMonitors and other local state are backed up in a
122 /// remote location (with local copies persisted immediately), it is anticipated that all
123 /// updates will return TemporaryFailure until the remote copies could be updated.
125 /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
126 /// different watchtower and cannot update with all watchtowers that were previously informed
127 /// of this channel). This will force-close the channel in question (which will generate one
128 /// final ChannelMonitorUpdate which must be delivered to at least one ChannelMonitor copy).
130 /// Should also be used to indicate a failure to update the local persisted copy of the channel
135 /// General Err type for ChannelMonitor actions. Generally, this implies that the data provided is
136 /// inconsistent with the ChannelMonitor being called. eg for ChannelMonitor::update_monitor this
137 /// means you tried to update a monitor for a different channel or the ChannelMonitorUpdate was
139 /// Contains a human-readable error message.
141 pub struct MonitorUpdateError(pub &'static str);
143 /// Simple structure send back by ManyChannelMonitor in case of HTLC detected onchain from a
144 /// forward channel and from which info are needed to update HTLC in a backward channel.
145 #[derive(Clone, PartialEq)]
146 pub struct HTLCUpdate {
147 pub(super) payment_hash: PaymentHash,
148 pub(super) payment_preimage: Option<PaymentPreimage>,
149 pub(super) source: HTLCSource
151 impl_writeable!(HTLCUpdate, 0, { payment_hash, payment_preimage, source });
153 /// Simple trait indicating ability to track a set of ChannelMonitors and multiplex events between
154 /// them. Generally should be implemented by keeping a local SimpleManyChannelMonitor and passing
155 /// events to it, while also taking any add/update_monitor events and passing them to some remote
158 /// In general, you must always have at least one local copy in memory, which must never fail to
159 /// update (as it is responsible for broadcasting the latest state in case the channel is closed),
160 /// and then persist it to various on-disk locations. If, for some reason, the in-memory copy fails
161 /// to update (eg out-of-memory or some other condition), you must immediately shut down without
162 /// taking any further action such as writing the current state to disk. This should likely be
163 /// accomplished via panic!() or abort().
165 /// Note that any updates to a channel's monitor *must* be applied to each instance of the
166 /// channel's monitor everywhere (including remote watchtowers) *before* this function returns. If
167 /// an update occurs and a remote watchtower is left with old state, it may broadcast transactions
168 /// which we have revoked, allowing our counterparty to claim all funds in the channel!
170 /// User needs to notify implementors of ManyChannelMonitor when a new block is connected or
171 /// disconnected using their `block_connected` and `block_disconnected` methods. However, rather
172 /// than calling these methods directly, the user should register implementors as listeners to the
173 /// BlockNotifier and call the BlockNotifier's `block_(dis)connected` methods, which will notify
174 /// all registered listeners in one go.
175 pub trait ManyChannelMonitor<ChanSigner: ChannelKeys>: Send + Sync {
176 /// Adds a monitor for the given `funding_txo`.
178 /// Implementer must also ensure that the funding_txo txid *and* outpoint are registered with
179 /// any relevant ChainWatchInterfaces such that the provided monitor receives block_connected
180 /// callbacks with the funding transaction, or any spends of it.
182 /// Further, the implementer must also ensure that each output returned in
183 /// monitor.get_outputs_to_watch() is registered to ensure that the provided monitor learns about
184 /// any spends of any of the outputs.
186 /// Any spends of outputs which should have been registered which aren't passed to
187 /// ChannelMonitors via block_connected may result in FUNDS LOSS.
188 fn add_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor<ChanSigner>) -> Result<(), ChannelMonitorUpdateErr>;
190 /// Updates a monitor for the given `funding_txo`.
192 /// Implementer must also ensure that the funding_txo txid *and* outpoint are registered with
193 /// any relevant ChainWatchInterfaces such that the provided monitor receives block_connected
194 /// callbacks with the funding transaction, or any spends of it.
196 /// Further, the implementer must also ensure that each output returned in
197 /// monitor.get_watch_outputs() is registered to ensure that the provided monitor learns about
198 /// any spends of any of the outputs.
200 /// Any spends of outputs which should have been registered which aren't passed to
201 /// ChannelMonitors via block_connected may result in FUNDS LOSS.
202 fn update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr>;
204 /// Used by ChannelManager to get list of HTLC resolved onchain and which needed to be updated
205 /// with success or failure.
207 /// You should probably just call through to
208 /// ChannelMonitor::get_and_clear_pending_htlcs_updated() for each ChannelMonitor and return
210 fn get_and_clear_pending_htlcs_updated(&self) -> Vec<HTLCUpdate>;
213 /// A simple implementation of a ManyChannelMonitor and ChainListener. Can be used to create a
214 /// watchtower or watch our own channels.
216 /// Note that you must provide your own key by which to refer to channels.
218 /// If you're accepting remote monitors (ie are implementing a watchtower), you must verify that
219 /// users cannot overwrite a given channel by providing a duplicate key. ie you should probably
220 /// index by a PublicKey which is required to sign any updates.
222 /// If you're using this for local monitoring of your own channels, you probably want to use
223 /// `OutPoint` as the key, which will give you a ManyChannelMonitor implementation.
224 pub struct SimpleManyChannelMonitor<Key, ChanSigner: ChannelKeys, T: Deref, F: Deref>
225 where T::Target: BroadcasterInterface,
226 F::Target: FeeEstimator
228 #[cfg(test)] // Used in ChannelManager tests to manipulate channels directly
229 pub monitors: Mutex<HashMap<Key, ChannelMonitor<ChanSigner>>>,
231 monitors: Mutex<HashMap<Key, ChannelMonitor<ChanSigner>>>,
232 chain_monitor: Arc<ChainWatchInterface>,
238 impl<'a, Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys, T: Deref + Sync + Send, F: Deref + Sync + Send>
239 ChainListener for SimpleManyChannelMonitor<Key, ChanSigner, T, F>
240 where T::Target: BroadcasterInterface,
241 F::Target: FeeEstimator
243 fn block_connected(&self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], _indexes_of_txn_matched: &[u32]) {
244 let block_hash = header.bitcoin_hash();
246 let mut monitors = self.monitors.lock().unwrap();
247 for monitor in monitors.values_mut() {
248 let txn_outputs = monitor.block_connected(txn_matched, height, &block_hash, &*self.broadcaster, &*self.fee_estimator);
250 for (ref txid, ref outputs) in txn_outputs {
251 for (idx, output) in outputs.iter().enumerate() {
252 self.chain_monitor.install_watch_outpoint((txid.clone(), idx as u32), &output.script_pubkey);
259 fn block_disconnected(&self, header: &BlockHeader, disconnected_height: u32) {
260 let block_hash = header.bitcoin_hash();
261 let mut monitors = self.monitors.lock().unwrap();
262 for monitor in monitors.values_mut() {
263 monitor.block_disconnected(disconnected_height, &block_hash, &*self.broadcaster, &*self.fee_estimator);
268 impl<Key : Send + cmp::Eq + hash::Hash + 'static, ChanSigner: ChannelKeys, T: Deref, F: Deref> SimpleManyChannelMonitor<Key, ChanSigner, T, F>
269 where T::Target: BroadcasterInterface,
270 F::Target: FeeEstimator
272 /// Creates a new object which can be used to monitor several channels given the chain
273 /// interface with which to register to receive notifications.
274 pub fn new(chain_monitor: Arc<ChainWatchInterface>, broadcaster: T, logger: Arc<Logger>, feeest: F) -> SimpleManyChannelMonitor<Key, ChanSigner, T, F> {
275 let res = SimpleManyChannelMonitor {
276 monitors: Mutex::new(HashMap::new()),
280 fee_estimator: feeest,
286 /// Adds or updates the monitor which monitors the channel referred to by the given key.
287 pub fn add_monitor_by_key(&self, key: Key, monitor: ChannelMonitor<ChanSigner>) -> Result<(), MonitorUpdateError> {
288 let mut monitors = self.monitors.lock().unwrap();
289 let entry = match monitors.entry(key) {
290 hash_map::Entry::Occupied(_) => return Err(MonitorUpdateError("Channel monitor for given key is already present")),
291 hash_map::Entry::Vacant(e) => e,
293 match monitor.onchain_detection.funding_info {
295 return Err(MonitorUpdateError("Try to update a useless monitor without funding_txo !"));
297 Some((ref outpoint, ref script)) => {
298 log_trace!(self, "Got new Channel Monitor for channel {}", log_bytes!(outpoint.to_channel_id()[..]));
299 self.chain_monitor.install_watch_tx(&outpoint.txid, script);
300 self.chain_monitor.install_watch_outpoint((outpoint.txid, outpoint.index as u32), script);
303 for (txid, outputs) in monitor.get_outputs_to_watch().iter() {
304 for (idx, script) in outputs.iter().enumerate() {
305 self.chain_monitor.install_watch_outpoint((*txid, idx as u32), script);
308 entry.insert(monitor);
312 /// Updates the monitor which monitors the channel referred to by the given key.
313 pub fn update_monitor_by_key(&self, key: Key, update: ChannelMonitorUpdate) -> Result<(), MonitorUpdateError> {
314 let mut monitors = self.monitors.lock().unwrap();
315 match monitors.get_mut(&key) {
316 Some(orig_monitor) => {
317 log_trace!(self, "Updating Channel Monitor for channel {}", log_funding_info!(orig_monitor.onchain_detection));
318 orig_monitor.update_monitor(update, &self.broadcaster)
320 None => Err(MonitorUpdateError("No such monitor registered"))
325 impl<ChanSigner: ChannelKeys, T: Deref + Sync + Send, F: Deref + Sync + Send> ManyChannelMonitor<ChanSigner> for SimpleManyChannelMonitor<OutPoint, ChanSigner, T, F>
326 where T::Target: BroadcasterInterface,
327 F::Target: FeeEstimator
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> events::EventsProvider for SimpleManyChannelMonitor<Key, ChanSigner, T, F>
353 where T::Target: BroadcasterInterface,
354 F::Target: FeeEstimator
356 fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
357 let mut pending_events = Vec::new();
358 for chan in self.monitors.lock().unwrap().values_mut() {
359 pending_events.append(&mut chan.get_and_clear_pending_events());
365 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
366 /// instead claiming it in its own individual transaction.
367 pub(crate) const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
368 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
369 /// HTLC-Success transaction.
370 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
371 /// transaction confirmed (and we use it in a few more, equivalent, places).
372 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 6;
373 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
374 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
375 /// copies of ChannelMonitors, including watchtowers). We could enforce the contract by failing
376 /// at CLTV expiration height but giving a grace period to our peer may be profitable for us if he
377 /// can provide an over-late preimage. Nevertheless, grace period has to be accounted in our
378 /// CLTV_EXPIRY_DELTA to be secure. Following this policy we may decrease the rate of channel failures
379 /// due to expiration but increase the cost of funds being locked longuer in case of failure.
380 /// This delay also cover a low-power peer being slow to process blocks and so being behind us on
381 /// accurate block height.
382 /// In case of onchain failure to be pass backward we may see the last block of ANTI_REORG_DELAY
383 /// with at worst this delay, so we are not only using this value as a mercy for them but also
384 /// us as a safeguard to delay with enough time.
385 pub(crate) const LATENCY_GRACE_PERIOD_BLOCKS: u32 = 3;
386 /// Number of blocks we wait on seeing a HTLC output being solved before we fail corresponding inbound
387 /// HTLCs. This prevents us from failing backwards and then getting a reorg resulting in us losing money.
388 /// We use also this delay to be sure we can remove our in-flight claim txn from bump candidates buffer.
389 /// It may cause spurrious generation of bumped claim txn but that's allright given the outpoint is already
390 /// solved by a previous claim tx. What we want to avoid is reorg evicting our claim tx and us not
391 /// keeping bumping another claim tx to solve the outpoint.
392 pub(crate) const ANTI_REORG_DELAY: u32 = 6;
394 struct OnchainDetection<ChanSigner: ChannelKeys> {
396 funding_info: Option<(OutPoint, Script)>,
397 current_remote_commitment_txid: Option<Sha256dHash>,
398 prev_remote_commitment_txid: Option<Sha256dHash>,
401 #[cfg(any(test, feature = "fuzztarget"))]
402 impl<ChanSigner: ChannelKeys> PartialEq for OnchainDetection<ChanSigner> {
403 fn eq(&self, other: &Self) -> bool {
404 self.keys.pubkeys() == other.keys.pubkeys()
408 #[derive(Clone, PartialEq)]
409 struct LocalSignedTx {
410 /// txid of the transaction in tx, just used to make comparison faster
412 revocation_key: PublicKey,
413 a_htlc_key: PublicKey,
414 b_htlc_key: PublicKey,
415 delayed_payment_key: PublicKey,
416 per_commitment_point: PublicKey,
418 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
421 /// When ChannelMonitor discovers an onchain outpoint being a step of a channel and that it needs
422 /// to generate a tx to push channel state forward, we cache outpoint-solving tx material to build
423 /// a new bumped one in case of lenghty confirmation delay
424 #[derive(Clone, PartialEq)]
425 pub(crate) enum InputMaterial {
427 witness_script: Script,
428 pubkey: Option<PublicKey>,
434 witness_script: Script,
436 preimage: Option<PaymentPreimage>,
441 preimage: Option<PaymentPreimage>,
449 impl Writeable for InputMaterial {
450 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
452 &InputMaterial::Revoked { ref witness_script, ref pubkey, ref key, ref is_htlc, ref amount} => {
453 writer.write_all(&[0; 1])?;
454 witness_script.write(writer)?;
455 pubkey.write(writer)?;
456 writer.write_all(&key[..])?;
457 is_htlc.write(writer)?;
458 writer.write_all(&byte_utils::be64_to_array(*amount))?;
460 &InputMaterial::RemoteHTLC { ref witness_script, ref key, ref preimage, ref amount, ref locktime } => {
461 writer.write_all(&[1; 1])?;
462 witness_script.write(writer)?;
464 preimage.write(writer)?;
465 writer.write_all(&byte_utils::be64_to_array(*amount))?;
466 writer.write_all(&byte_utils::be32_to_array(*locktime))?;
468 &InputMaterial::LocalHTLC { ref preimage, ref amount } => {
469 writer.write_all(&[2; 1])?;
470 preimage.write(writer)?;
471 writer.write_all(&byte_utils::be64_to_array(*amount))?;
473 &InputMaterial::Funding { ref channel_value } => {
474 writer.write_all(&[3; 1])?;
475 channel_value.write(writer)?;
482 impl Readable for InputMaterial {
483 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
484 let input_material = match <u8 as Readable>::read(reader)? {
486 let witness_script = Readable::read(reader)?;
487 let pubkey = Readable::read(reader)?;
488 let key = Readable::read(reader)?;
489 let is_htlc = Readable::read(reader)?;
490 let amount = Readable::read(reader)?;
491 InputMaterial::Revoked {
500 let witness_script = Readable::read(reader)?;
501 let key = Readable::read(reader)?;
502 let preimage = Readable::read(reader)?;
503 let amount = Readable::read(reader)?;
504 let locktime = Readable::read(reader)?;
505 InputMaterial::RemoteHTLC {
514 let preimage = Readable::read(reader)?;
515 let amount = Readable::read(reader)?;
516 InputMaterial::LocalHTLC {
522 let channel_value = Readable::read(reader)?;
523 InputMaterial::Funding {
527 _ => return Err(DecodeError::InvalidValue),
533 /// ClaimRequest is a descriptor structure to communicate between detection
534 /// and reaction module. They are generated by ChannelMonitor while parsing
535 /// onchain txn leaked from a channel and handed over to OnchainTxHandler which
536 /// is responsible for opportunistic aggregation, selecting and enforcing
537 /// bumping logic, building and signing transactions.
538 pub(crate) struct ClaimRequest {
539 // Block height before which claiming is exclusive to one party,
540 // after reaching it, claiming may be contentious.
541 pub(crate) absolute_timelock: u32,
542 // Timeout tx must have nLocktime set which means aggregating multiple
543 // ones must take the higher nLocktime among them to satisfy all of them.
544 // Sadly it has few pitfalls, a) it takes longuer to get fund back b) CLTV_DELTA
545 // of a sooner-HTLC could be swallowed by the highest nLocktime of the HTLC set.
546 // Do simplify we mark them as non-aggregable.
547 pub(crate) aggregable: bool,
548 // Basic bitcoin outpoint (txid, vout)
549 pub(crate) outpoint: BitcoinOutPoint,
550 // Following outpoint type, set of data needed to generate transaction digest
551 // and satisfy witness program.
552 pub(crate) witness_data: InputMaterial
555 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
556 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
557 #[derive(Clone, PartialEq)]
559 /// HTLC output getting solved by a timeout, at maturation we pass upstream payment source information to solve
560 /// inbound HTLC in backward channel. Note, in case of preimage, we pass info to upstream without delay as we can
561 /// only win from it, so it's never an OnchainEvent
563 htlc_update: (HTLCSource, PaymentHash),
566 descriptor: SpendableOutputDescriptor,
570 const SERIALIZATION_VERSION: u8 = 1;
571 const MIN_SERIALIZATION_VERSION: u8 = 1;
573 #[cfg_attr(test, derive(PartialEq))]
575 pub(super) enum ChannelMonitorUpdateStep {
576 LatestLocalCommitmentTXInfo {
577 // TODO: We really need to not be generating a fully-signed transaction in Channel and
578 // passing it here, we need to hold off so that the ChanSigner can enforce a
579 // only-sign-local-state-for-broadcast once invariant:
580 commitment_tx: LocalCommitmentTransaction,
581 local_keys: chan_utils::TxCreationKeys,
583 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
585 LatestRemoteCommitmentTXInfo {
586 unsigned_commitment_tx: Transaction, // TODO: We should actually only need the txid here
587 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
588 commitment_number: u64,
589 their_revocation_point: PublicKey,
592 payment_preimage: PaymentPreimage,
598 /// Indicates our channel is likely a stale version, we're closing, but this update should
599 /// allow us to spend what is ours if our counterparty broadcasts their latest state.
600 RescueRemoteCommitmentTXInfo {
601 their_current_per_commitment_point: PublicKey,
603 /// Used to indicate that the no future updates will occur, and likely that the latest local
604 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
606 /// If set to false, we shouldn't broadcast the latest local commitment transaction as we
607 /// think we've fallen behind!
608 should_broadcast: bool,
612 impl Writeable for ChannelMonitorUpdateStep {
613 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
615 &ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { ref commitment_tx, ref local_keys, ref feerate_per_kw, ref htlc_outputs } => {
617 commitment_tx.write(w)?;
618 local_keys.write(w)?;
619 feerate_per_kw.write(w)?;
620 (htlc_outputs.len() as u64).write(w)?;
621 for &(ref output, ref signature, ref source) in htlc_outputs.iter() {
627 &ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { ref unsigned_commitment_tx, ref htlc_outputs, ref commitment_number, ref their_revocation_point } => {
629 unsigned_commitment_tx.write(w)?;
630 commitment_number.write(w)?;
631 their_revocation_point.write(w)?;
632 (htlc_outputs.len() as u64).write(w)?;
633 for &(ref output, ref source) in htlc_outputs.iter() {
635 source.as_ref().map(|b| b.as_ref()).write(w)?;
638 &ChannelMonitorUpdateStep::PaymentPreimage { ref payment_preimage } => {
640 payment_preimage.write(w)?;
642 &ChannelMonitorUpdateStep::CommitmentSecret { ref idx, ref secret } => {
647 &ChannelMonitorUpdateStep::RescueRemoteCommitmentTXInfo { ref their_current_per_commitment_point } => {
649 their_current_per_commitment_point.write(w)?;
651 &ChannelMonitorUpdateStep::ChannelForceClosed { ref should_broadcast } => {
653 should_broadcast.write(w)?;
659 impl Readable for ChannelMonitorUpdateStep {
660 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
661 match Readable::read(r)? {
663 Ok(ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo {
664 commitment_tx: Readable::read(r)?,
665 local_keys: Readable::read(r)?,
666 feerate_per_kw: Readable::read(r)?,
668 let len: u64 = Readable::read(r)?;
669 let mut res = Vec::new();
671 res.push((Readable::read(r)?, Readable::read(r)?, Readable::read(r)?));
678 Ok(ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo {
679 unsigned_commitment_tx: Readable::read(r)?,
680 commitment_number: Readable::read(r)?,
681 their_revocation_point: Readable::read(r)?,
683 let len: u64 = Readable::read(r)?;
684 let mut res = Vec::new();
686 res.push((Readable::read(r)?, <Option<HTLCSource> as Readable>::read(r)?.map(|o| Box::new(o))));
693 Ok(ChannelMonitorUpdateStep::PaymentPreimage {
694 payment_preimage: Readable::read(r)?,
698 Ok(ChannelMonitorUpdateStep::CommitmentSecret {
699 idx: Readable::read(r)?,
700 secret: Readable::read(r)?,
704 Ok(ChannelMonitorUpdateStep::RescueRemoteCommitmentTXInfo {
705 their_current_per_commitment_point: Readable::read(r)?,
709 Ok(ChannelMonitorUpdateStep::ChannelForceClosed {
710 should_broadcast: Readable::read(r)?
713 _ => Err(DecodeError::InvalidValue),
718 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
719 /// on-chain transactions to ensure no loss of funds occurs.
721 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
722 /// information and are actively monitoring the chain.
724 /// Pending Events or updated HTLCs which have not yet been read out by
725 /// get_and_clear_pending_htlcs_updated or get_and_clear_pending_events are serialized to disk and
726 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
727 /// gotten are fully handled before re-serializing the new state.
728 pub struct ChannelMonitor<ChanSigner: ChannelKeys> {
729 latest_update_id: u64,
730 commitment_transaction_number_obscure_factor: u64,
732 destination_script: Script,
733 broadcasted_local_revokable_script: Option<(Script, SecretKey, Script)>,
734 broadcasted_remote_payment_script: Option<(Script, SecretKey)>,
735 shutdown_script: Script,
737 onchain_detection: OnchainDetection<ChanSigner>,
738 their_htlc_base_key: Option<PublicKey>,
739 their_delayed_payment_base_key: Option<PublicKey>,
740 funding_redeemscript: Option<Script>,
741 channel_value_satoshis: Option<u64>,
742 // first is the idx of the first of the two revocation points
743 their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
745 our_to_self_delay: u16,
746 their_to_self_delay: Option<u16>,
748 commitment_secrets: CounterpartyCommitmentSecrets,
749 remote_claimable_outpoints: HashMap<Sha256dHash, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
750 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
751 /// Nor can we figure out their commitment numbers without the commitment transaction they are
752 /// spending. Thus, in order to claim them via revocation key, we track all the remote
753 /// commitment transactions which we find on-chain, mapping them to the commitment number which
754 /// can be used to derive the revocation key and claim the transactions.
755 remote_commitment_txn_on_chain: HashMap<Sha256dHash, (u64, Vec<Script>)>,
756 /// Cache used to make pruning of payment_preimages faster.
757 /// Maps payment_hash values to commitment numbers for remote transactions for non-revoked
758 /// remote transactions (ie should remain pretty small).
759 /// Serialized to disk but should generally not be sent to Watchtowers.
760 remote_hash_commitment_number: HashMap<PaymentHash, u64>,
762 // We store two local commitment transactions to avoid any race conditions where we may update
763 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
764 // various monitors for one channel being out of sync, and us broadcasting a local
765 // transaction for which we have deleted claim information on some watchtowers.
766 prev_local_signed_commitment_tx: Option<LocalSignedTx>,
767 current_local_signed_commitment_tx: Option<LocalSignedTx>,
769 // Used just for ChannelManager to make sure it has the latest channel data during
771 current_remote_commitment_number: u64,
772 // Used just for ChannelManager to make sure it has the latest channel data during
774 current_local_commitment_number: u64,
776 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
778 pending_htlcs_updated: Vec<HTLCUpdate>,
779 pending_events: Vec<events::Event>,
781 // Used to track onchain events, i.e transactions parts of channels confirmed on chain, on which
782 // we have to take actions once they reach enough confs. Key is a block height timer, i.e we enforce
783 // actions when we receive a block with given height. Actions depend on OnchainEvent type.
784 onchain_events_waiting_threshold_conf: HashMap<u32, Vec<OnchainEvent>>,
786 // If we get serialized out and re-read, we need to make sure that the chain monitoring
787 // interface knows about the TXOs that we want to be notified of spends of. We could probably
788 // be smart and derive them from the above storage fields, but its much simpler and more
789 // Obviously Correct (tm) if we just keep track of them explicitly.
790 outputs_to_watch: HashMap<Sha256dHash, Vec<Script>>,
793 pub onchain_tx_handler: OnchainTxHandler<ChanSigner>,
795 onchain_tx_handler: OnchainTxHandler<ChanSigner>,
797 // Used to detect programming bug due to unsafe monitor update sequence { ChannelForceClosed, LatestLocalCommitmentTXInfo }
798 lockdown_from_offchain: bool,
800 // We simply modify last_block_hash in Channel's block_connected so that serialization is
801 // consistent but hopefully the users' copy handles block_connected in a consistent way.
802 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
803 // their last_block_hash from its state and not based on updated copies that didn't run through
804 // the full block_connected).
805 pub(crate) last_block_hash: Sha256dHash,
806 secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
810 #[cfg(any(test, feature = "fuzztarget"))]
811 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
812 /// underlying object
813 impl<ChanSigner: ChannelKeys> PartialEq for ChannelMonitor<ChanSigner> {
814 fn eq(&self, other: &Self) -> bool {
815 if self.latest_update_id != other.latest_update_id ||
816 self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
817 self.destination_script != other.destination_script ||
818 self.broadcasted_local_revokable_script != other.broadcasted_local_revokable_script ||
819 self.broadcasted_remote_payment_script != other.broadcasted_remote_payment_script ||
820 self.onchain_detection != other.onchain_detection ||
821 self.their_htlc_base_key != other.their_htlc_base_key ||
822 self.their_delayed_payment_base_key != other.their_delayed_payment_base_key ||
823 self.funding_redeemscript != other.funding_redeemscript ||
824 self.channel_value_satoshis != other.channel_value_satoshis ||
825 self.their_cur_revocation_points != other.their_cur_revocation_points ||
826 self.our_to_self_delay != other.our_to_self_delay ||
827 self.their_to_self_delay != other.their_to_self_delay ||
828 self.commitment_secrets != other.commitment_secrets ||
829 self.remote_claimable_outpoints != other.remote_claimable_outpoints ||
830 self.remote_commitment_txn_on_chain != other.remote_commitment_txn_on_chain ||
831 self.remote_hash_commitment_number != other.remote_hash_commitment_number ||
832 self.prev_local_signed_commitment_tx != other.prev_local_signed_commitment_tx ||
833 self.current_remote_commitment_number != other.current_remote_commitment_number ||
834 self.current_local_commitment_number != other.current_local_commitment_number ||
835 self.current_local_signed_commitment_tx != other.current_local_signed_commitment_tx ||
836 self.payment_preimages != other.payment_preimages ||
837 self.pending_htlcs_updated != other.pending_htlcs_updated ||
838 self.pending_events.len() != other.pending_events.len() || // We trust events to round-trip properly
839 self.onchain_events_waiting_threshold_conf != other.onchain_events_waiting_threshold_conf ||
840 self.outputs_to_watch != other.outputs_to_watch
849 impl<ChanSigner: ChannelKeys + Writeable> ChannelMonitor<ChanSigner> {
850 /// Serializes into a vec, with various modes for the exposed pub fns
851 fn write<W: Writer>(&self, writer: &mut W, for_local_storage: bool) -> Result<(), ::std::io::Error> {
852 //TODO: We still write out all the serialization here manually instead of using the fancy
853 //serialization framework we have, we should migrate things over to it.
854 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
855 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
857 self.latest_update_id.write(writer)?;
859 // Set in initial Channel-object creation, so should always be set by now:
860 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
862 self.destination_script.write(writer)?;
863 if let Some(ref broadcasted_local_revokable_script) = self.broadcasted_local_revokable_script {
864 writer.write_all(&[0; 1])?;
865 broadcasted_local_revokable_script.0.write(writer)?;
866 broadcasted_local_revokable_script.1.write(writer)?;
867 broadcasted_local_revokable_script.2.write(writer)?;
869 writer.write_all(&[1; 1])?;
872 if let Some(ref broadcasted_remote_payment_script) = self.broadcasted_remote_payment_script {
873 writer.write_all(&[0; 1])?;
874 broadcasted_remote_payment_script.0.write(writer)?;
875 broadcasted_remote_payment_script.1.write(writer)?;
877 writer.write_all(&[1; 1])?;
879 self.shutdown_script.write(writer)?;
881 self.onchain_detection.keys.write(writer)?;
882 match self.onchain_detection.funding_info {
883 Some((ref outpoint, ref script)) => {
884 writer.write_all(&outpoint.txid[..])?;
885 writer.write_all(&byte_utils::be16_to_array(outpoint.index))?;
886 script.write(writer)?;
889 debug_assert!(false, "Try to serialize a useless Local monitor !");
892 self.onchain_detection.current_remote_commitment_txid.write(writer)?;
893 self.onchain_detection.prev_remote_commitment_txid.write(writer)?;
895 writer.write_all(&self.their_htlc_base_key.as_ref().unwrap().serialize())?;
896 writer.write_all(&self.their_delayed_payment_base_key.as_ref().unwrap().serialize())?;
897 self.funding_redeemscript.as_ref().unwrap().write(writer)?;
898 self.channel_value_satoshis.unwrap().write(writer)?;
900 match self.their_cur_revocation_points {
901 Some((idx, pubkey, second_option)) => {
902 writer.write_all(&byte_utils::be48_to_array(idx))?;
903 writer.write_all(&pubkey.serialize())?;
904 match second_option {
905 Some(second_pubkey) => {
906 writer.write_all(&second_pubkey.serialize())?;
909 writer.write_all(&[0; 33])?;
914 writer.write_all(&byte_utils::be48_to_array(0))?;
918 writer.write_all(&byte_utils::be16_to_array(self.our_to_self_delay))?;
919 writer.write_all(&byte_utils::be16_to_array(self.their_to_self_delay.unwrap()))?;
921 self.commitment_secrets.write(writer)?;
923 macro_rules! serialize_htlc_in_commitment {
924 ($htlc_output: expr) => {
925 writer.write_all(&[$htlc_output.offered as u8; 1])?;
926 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
927 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
928 writer.write_all(&$htlc_output.payment_hash.0[..])?;
929 $htlc_output.transaction_output_index.write(writer)?;
933 writer.write_all(&byte_utils::be64_to_array(self.remote_claimable_outpoints.len() as u64))?;
934 for (ref txid, ref htlc_infos) in self.remote_claimable_outpoints.iter() {
935 writer.write_all(&txid[..])?;
936 writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
937 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
938 serialize_htlc_in_commitment!(htlc_output);
939 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
943 writer.write_all(&byte_utils::be64_to_array(self.remote_commitment_txn_on_chain.len() as u64))?;
944 for (ref txid, &(commitment_number, ref txouts)) in self.remote_commitment_txn_on_chain.iter() {
945 writer.write_all(&txid[..])?;
946 writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
947 (txouts.len() as u64).write(writer)?;
948 for script in txouts.iter() {
949 script.write(writer)?;
953 if for_local_storage {
954 writer.write_all(&byte_utils::be64_to_array(self.remote_hash_commitment_number.len() as u64))?;
955 for (ref payment_hash, commitment_number) in self.remote_hash_commitment_number.iter() {
956 writer.write_all(&payment_hash.0[..])?;
957 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
960 writer.write_all(&byte_utils::be64_to_array(0))?;
963 macro_rules! serialize_local_tx {
964 ($local_tx: expr) => {
965 $local_tx.txid.write(writer)?;
966 writer.write_all(&$local_tx.revocation_key.serialize())?;
967 writer.write_all(&$local_tx.a_htlc_key.serialize())?;
968 writer.write_all(&$local_tx.b_htlc_key.serialize())?;
969 writer.write_all(&$local_tx.delayed_payment_key.serialize())?;
970 writer.write_all(&$local_tx.per_commitment_point.serialize())?;
972 writer.write_all(&byte_utils::be64_to_array($local_tx.feerate_per_kw))?;
973 writer.write_all(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64))?;
974 for &(ref htlc_output, ref sig, ref htlc_source) in $local_tx.htlc_outputs.iter() {
975 serialize_htlc_in_commitment!(htlc_output);
976 if let &Some(ref their_sig) = sig {
978 writer.write_all(&their_sig.serialize_compact())?;
982 htlc_source.write(writer)?;
987 if let Some(ref prev_local_tx) = self.prev_local_signed_commitment_tx {
988 writer.write_all(&[1; 1])?;
989 serialize_local_tx!(prev_local_tx);
991 writer.write_all(&[0; 1])?;
994 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
995 writer.write_all(&[1; 1])?;
996 serialize_local_tx!(cur_local_tx);
998 writer.write_all(&[0; 1])?;
1001 if for_local_storage {
1002 writer.write_all(&byte_utils::be48_to_array(self.current_remote_commitment_number))?;
1004 writer.write_all(&byte_utils::be48_to_array(0))?;
1007 if for_local_storage {
1008 writer.write_all(&byte_utils::be48_to_array(self.current_local_commitment_number))?;
1010 writer.write_all(&byte_utils::be48_to_array(0))?;
1013 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
1014 for payment_preimage in self.payment_preimages.values() {
1015 writer.write_all(&payment_preimage.0[..])?;
1018 writer.write_all(&byte_utils::be64_to_array(self.pending_htlcs_updated.len() as u64))?;
1019 for data in self.pending_htlcs_updated.iter() {
1020 data.write(writer)?;
1023 writer.write_all(&byte_utils::be64_to_array(self.pending_events.len() as u64))?;
1024 for event in self.pending_events.iter() {
1025 event.write(writer)?;
1028 self.last_block_hash.write(writer)?;
1030 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_waiting_threshold_conf.len() as u64))?;
1031 for (ref target, ref events) in self.onchain_events_waiting_threshold_conf.iter() {
1032 writer.write_all(&byte_utils::be32_to_array(**target))?;
1033 writer.write_all(&byte_utils::be64_to_array(events.len() as u64))?;
1034 for ev in events.iter() {
1036 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1038 htlc_update.0.write(writer)?;
1039 htlc_update.1.write(writer)?;
1041 OnchainEvent::MaturingOutput { ref descriptor } => {
1043 descriptor.write(writer)?;
1049 (self.outputs_to_watch.len() as u64).write(writer)?;
1050 for (txid, output_scripts) in self.outputs_to_watch.iter() {
1051 txid.write(writer)?;
1052 (output_scripts.len() as u64).write(writer)?;
1053 for script in output_scripts.iter() {
1054 script.write(writer)?;
1057 self.onchain_tx_handler.write(writer)?;
1059 self.lockdown_from_offchain.write(writer)?;
1064 /// Writes this monitor into the given writer, suitable for writing to disk.
1066 /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
1067 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
1068 /// the "reorg path" (ie not just starting at the same height but starting at the highest
1069 /// common block that appears on your best chain as well as on the chain which contains the
1070 /// last block hash returned) upon deserializing the object!
1071 pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
1072 self.write(writer, true)
1075 /// Encodes this monitor into the given writer, suitable for sending to a remote watchtower
1077 /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
1078 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
1079 /// the "reorg path" (ie not just starting at the same height but starting at the highest
1080 /// common block that appears on your best chain as well as on the chain which contains the
1081 /// last block hash returned) upon deserializing the object!
1082 pub fn write_for_watchtower<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
1083 self.write(writer, false)
1087 impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
1088 pub(super) fn new(keys: ChanSigner, shutdown_pubkey: &PublicKey,
1089 our_to_self_delay: u16, destination_script: &Script, funding_info: (OutPoint, Script),
1090 their_htlc_base_key: &PublicKey, their_delayed_payment_base_key: &PublicKey,
1091 their_to_self_delay: u16, funding_redeemscript: Script, channel_value_satoshis: u64,
1092 commitment_transaction_number_obscure_factor: u64,
1093 logger: Arc<Logger>) -> ChannelMonitor<ChanSigner> {
1095 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
1096 let our_channel_close_key_hash = Hash160::hash(&shutdown_pubkey.serialize());
1097 let shutdown_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
1099 let onchain_detection = OnchainDetection {
1101 funding_info: Some(funding_info.clone()),
1102 current_remote_commitment_txid: None,
1103 prev_remote_commitment_txid: None,
1107 latest_update_id: 0,
1108 commitment_transaction_number_obscure_factor,
1110 destination_script: destination_script.clone(),
1111 broadcasted_local_revokable_script: None,
1112 broadcasted_remote_payment_script: None,
1115 onchain_detection: onchain_detection,
1116 their_htlc_base_key: Some(their_htlc_base_key.clone()),
1117 their_delayed_payment_base_key: Some(their_delayed_payment_base_key.clone()),
1118 funding_redeemscript: Some(funding_redeemscript.clone()),
1119 channel_value_satoshis: Some(channel_value_satoshis),
1120 their_cur_revocation_points: None,
1122 our_to_self_delay: our_to_self_delay,
1123 their_to_self_delay: Some(their_to_self_delay),
1125 commitment_secrets: CounterpartyCommitmentSecrets::new(),
1126 remote_claimable_outpoints: HashMap::new(),
1127 remote_commitment_txn_on_chain: HashMap::new(),
1128 remote_hash_commitment_number: HashMap::new(),
1130 prev_local_signed_commitment_tx: None,
1131 current_local_signed_commitment_tx: None,
1132 current_remote_commitment_number: 1 << 48,
1133 current_local_commitment_number: 0xffff_ffff_ffff,
1135 payment_preimages: HashMap::new(),
1136 pending_htlcs_updated: Vec::new(),
1137 pending_events: Vec::new(),
1139 onchain_events_waiting_threshold_conf: HashMap::new(),
1140 outputs_to_watch: HashMap::new(),
1142 onchain_tx_handler: OnchainTxHandler::new(destination_script.clone(), keys, funding_redeemscript, their_to_self_delay, logger.clone()),
1144 lockdown_from_offchain: false,
1146 last_block_hash: Default::default(),
1147 secp_ctx: Secp256k1::new(),
1152 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
1153 /// needed by local commitment transactions HTCLs nor by remote ones. Unless we haven't already seen remote
1154 /// commitment transaction's secret, they are de facto pruned (we can use revocation key).
1155 pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
1156 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
1157 return Err(MonitorUpdateError("Previous secret did not match new one"));
1160 // Prune HTLCs from the previous remote commitment tx so we don't generate failure/fulfill
1161 // events for now-revoked/fulfilled HTLCs.
1162 if let Some(txid) = self.onchain_detection.prev_remote_commitment_txid.take() {
1163 for &mut (_, ref mut source) in self.remote_claimable_outpoints.get_mut(&txid).unwrap() {
1168 if !self.payment_preimages.is_empty() {
1169 let local_signed_commitment_tx = self.current_local_signed_commitment_tx.as_ref().expect("Channel needs at least an initial commitment tx !");
1170 let prev_local_signed_commitment_tx = self.prev_local_signed_commitment_tx.as_ref();
1171 let min_idx = self.get_min_seen_secret();
1172 let remote_hash_commitment_number = &mut self.remote_hash_commitment_number;
1174 self.payment_preimages.retain(|&k, _| {
1175 for &(ref htlc, _, _) in &local_signed_commitment_tx.htlc_outputs {
1176 if k == htlc.payment_hash {
1180 if let Some(prev_local_commitment_tx) = prev_local_signed_commitment_tx {
1181 for &(ref htlc, _, _) in prev_local_commitment_tx.htlc_outputs.iter() {
1182 if k == htlc.payment_hash {
1187 let contains = if let Some(cn) = remote_hash_commitment_number.get(&k) {
1194 remote_hash_commitment_number.remove(&k);
1203 /// Informs this monitor of the latest remote (ie non-broadcastable) commitment transaction.
1204 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
1205 /// possibly future revocation/preimage information) to claim outputs where possible.
1206 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
1207 pub(super) fn provide_latest_remote_commitment_tx_info(&mut self, unsigned_commitment_tx: &Transaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>, commitment_number: u64, their_revocation_point: PublicKey) {
1208 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
1209 // so that a remote monitor doesn't learn anything unless there is a malicious close.
1210 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
1212 for &(ref htlc, _) in &htlc_outputs {
1213 self.remote_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
1216 let new_txid = unsigned_commitment_tx.txid();
1217 log_trace!(self, "Tracking new remote commitment transaction with txid {} at commitment number {} with {} HTLC outputs", new_txid, commitment_number, htlc_outputs.len());
1218 log_trace!(self, "New potential remote commitment transaction: {}", encode::serialize_hex(unsigned_commitment_tx));
1219 self.onchain_detection.prev_remote_commitment_txid = self.onchain_detection.current_remote_commitment_txid.take();
1220 self.onchain_detection.current_remote_commitment_txid = Some(new_txid);
1221 self.remote_claimable_outpoints.insert(new_txid, htlc_outputs);
1222 self.current_remote_commitment_number = commitment_number;
1223 //TODO: Merge this into the other per-remote-transaction output storage stuff
1224 match self.their_cur_revocation_points {
1225 Some(old_points) => {
1226 if old_points.0 == commitment_number + 1 {
1227 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
1228 } else if old_points.0 == commitment_number + 2 {
1229 if let Some(old_second_point) = old_points.2 {
1230 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
1232 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1235 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1239 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1244 pub(super) fn provide_rescue_remote_commitment_tx_info(&mut self, their_revocation_point: PublicKey) {
1245 if let Ok(payment_key) = chan_utils::derive_public_key(&self.secp_ctx, &their_revocation_point, &self.onchain_detection.keys.pubkeys().payment_basepoint) {
1246 let to_remote_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0)
1247 .push_slice(&Hash160::hash(&payment_key.serialize())[..])
1249 if let Ok(to_remote_key) = chan_utils::derive_private_key(&self.secp_ctx, &their_revocation_point, &self.onchain_detection.keys.payment_base_key()) {
1250 self.broadcasted_remote_payment_script = Some((to_remote_script, to_remote_key));
1255 /// Informs this monitor of the latest local (ie broadcastable) commitment transaction. The
1256 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
1257 /// is important that any clones of this channel monitor (including remote clones) by kept
1258 /// up-to-date as our local commitment transaction is updated.
1259 /// Panics if set_their_to_self_delay has never been called.
1260 pub(super) fn provide_latest_local_commitment_tx_info(&mut self, mut commitment_tx: LocalCommitmentTransaction, local_keys: chan_utils::TxCreationKeys, feerate_per_kw: u64, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), MonitorUpdateError> {
1261 if self.their_to_self_delay.is_none() {
1262 return Err(MonitorUpdateError("Got a local commitment tx info update before we'd set basic information about the channel"));
1264 let txid = commitment_tx.txid();
1265 let sequence = commitment_tx.without_valid_witness().input[0].sequence as u64;
1266 let locktime = commitment_tx.without_valid_witness().lock_time as u64;
1267 let mut htlcs = Vec::with_capacity(htlc_outputs.len());
1268 for htlc in htlc_outputs.clone() {
1269 if let Some(_) = htlc.0.transaction_output_index {
1270 htlcs.push((htlc.0, htlc.1, None));
1273 commitment_tx.set_htlc_cache(local_keys.clone(), feerate_per_kw, htlcs);
1274 // Returning a monitor error before updating tracking points means in case of using
1275 // a concurrent watchtower implementation for same channel, if this one doesn't
1276 // reject update as we do, you MAY have the latest local valid commitment tx onchain
1277 // for which you want to spend outputs. We're NOT robust again this scenario right
1278 // now but we should consider it later.
1279 if let Err(_) = self.onchain_tx_handler.provide_latest_local_tx(commitment_tx) {
1280 return Err(MonitorUpdateError("Local commitment signed has already been signed, no further update of LOCAL commitment transaction is allowed"));
1282 self.current_local_commitment_number = 0xffff_ffff_ffff - ((((sequence & 0xffffff) << 3*8) | (locktime as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
1283 self.prev_local_signed_commitment_tx = self.current_local_signed_commitment_tx.take();
1284 self.current_local_signed_commitment_tx = Some(LocalSignedTx {
1286 revocation_key: local_keys.revocation_key,
1287 a_htlc_key: local_keys.a_htlc_key,
1288 b_htlc_key: local_keys.b_htlc_key,
1289 delayed_payment_key: local_keys.a_delayed_payment_key,
1290 per_commitment_point: local_keys.per_commitment_point,
1292 htlc_outputs: htlc_outputs,
1297 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
1298 /// commitment_tx_infos which contain the payment hash have been revoked.
1299 pub(super) fn provide_payment_preimage(&mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage) {
1300 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
1303 pub(super) fn broadcast_latest_local_commitment_txn<B: Deref>(&mut self, broadcaster: &B)
1304 where B::Target: BroadcasterInterface,
1306 for tx in self.get_latest_local_commitment_txn().iter() {
1307 broadcaster.broadcast_transaction(tx);
1311 /// Used in Channel to cheat wrt the update_ids since it plays games, will be removed soon!
1312 pub(super) fn update_monitor_ooo(&mut self, mut updates: ChannelMonitorUpdate) -> Result<(), MonitorUpdateError> {
1313 for update in updates.updates.drain(..) {
1315 ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { commitment_tx, local_keys, feerate_per_kw, htlc_outputs } => {
1316 if self.lockdown_from_offchain { panic!(); }
1317 self.provide_latest_local_commitment_tx_info(commitment_tx, local_keys, feerate_per_kw, htlc_outputs)?
1319 ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
1320 self.provide_latest_remote_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point),
1321 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
1322 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
1323 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
1324 self.provide_secret(idx, secret)?,
1325 ChannelMonitorUpdateStep::RescueRemoteCommitmentTXInfo { their_current_per_commitment_point } =>
1326 self.provide_rescue_remote_commitment_tx_info(their_current_per_commitment_point),
1327 ChannelMonitorUpdateStep::ChannelForceClosed { .. } => {},
1330 self.latest_update_id = updates.update_id;
1334 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
1337 /// panics if the given update is not the next update by update_id.
1338 pub fn update_monitor<B: Deref>(&mut self, mut updates: ChannelMonitorUpdate, broadcaster: &B) -> Result<(), MonitorUpdateError>
1339 where B::Target: BroadcasterInterface,
1341 if self.latest_update_id + 1 != updates.update_id {
1342 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
1344 for update in updates.updates.drain(..) {
1346 ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { commitment_tx, local_keys, feerate_per_kw, htlc_outputs } => {
1347 if self.lockdown_from_offchain { panic!(); }
1348 self.provide_latest_local_commitment_tx_info(commitment_tx, local_keys, feerate_per_kw, htlc_outputs)?
1350 ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
1351 self.provide_latest_remote_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point),
1352 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
1353 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
1354 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
1355 self.provide_secret(idx, secret)?,
1356 ChannelMonitorUpdateStep::RescueRemoteCommitmentTXInfo { their_current_per_commitment_point } =>
1357 self.provide_rescue_remote_commitment_tx_info(their_current_per_commitment_point),
1358 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
1359 self.lockdown_from_offchain = true;
1360 if should_broadcast {
1361 self.broadcast_latest_local_commitment_txn(broadcaster);
1363 log_error!(self, "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");
1368 self.latest_update_id = updates.update_id;
1372 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
1374 pub fn get_latest_update_id(&self) -> u64 {
1375 self.latest_update_id
1378 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
1379 pub fn get_funding_txo(&self) -> Option<OutPoint> {
1380 if let Some((outp, _)) = self.onchain_detection.funding_info {
1386 /// Gets a list of txids, with their output scripts (in the order they appear in the
1387 /// transaction), which we must learn about spends of via block_connected().
1388 pub fn get_outputs_to_watch(&self) -> &HashMap<Sha256dHash, Vec<Script>> {
1389 &self.outputs_to_watch
1392 /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
1393 /// Generally useful when deserializing as during normal operation the return values of
1394 /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
1395 /// that the get_funding_txo outpoint and transaction must also be monitored for!).
1396 pub fn get_monitored_outpoints(&self) -> Vec<(Sha256dHash, u32, &Script)> {
1397 let mut res = Vec::with_capacity(self.remote_commitment_txn_on_chain.len() * 2);
1398 for (ref txid, &(_, ref outputs)) in self.remote_commitment_txn_on_chain.iter() {
1399 for (idx, output) in outputs.iter().enumerate() {
1400 res.push(((*txid).clone(), idx as u32, output));
1406 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1407 /// ChannelManager via ManyChannelMonitor::get_and_clear_pending_htlcs_updated().
1408 pub fn get_and_clear_pending_htlcs_updated(&mut self) -> Vec<HTLCUpdate> {
1409 let mut ret = Vec::new();
1410 mem::swap(&mut ret, &mut self.pending_htlcs_updated);
1414 /// Gets the list of pending events which were generated by previous actions, clearing the list
1417 /// This is called by ManyChannelMonitor::get_and_clear_pending_events() and is equivalent to
1418 /// EventsProvider::get_and_clear_pending_events() except that it requires &mut self as we do
1419 /// no internal locking in ChannelMonitors.
1420 pub fn get_and_clear_pending_events(&mut self) -> Vec<events::Event> {
1421 let mut ret = Vec::new();
1422 mem::swap(&mut ret, &mut self.pending_events);
1426 /// Can only fail if idx is < get_min_seen_secret
1427 pub(super) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
1428 self.commitment_secrets.get_secret(idx)
1431 pub(super) fn get_min_seen_secret(&self) -> u64 {
1432 self.commitment_secrets.get_min_seen_secret()
1435 pub(super) fn get_cur_remote_commitment_number(&self) -> u64 {
1436 self.current_remote_commitment_number
1439 pub(super) fn get_cur_local_commitment_number(&self) -> u64 {
1440 self.current_local_commitment_number
1443 /// Attempts to claim a remote commitment transaction's outputs using the revocation key and
1444 /// data in remote_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
1445 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
1446 /// HTLC-Success/HTLC-Timeout transactions.
1447 /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
1448 /// revoked remote commitment tx
1449 fn check_spend_remote_transaction(&mut self, tx: &Transaction, height: u32) -> (Vec<ClaimRequest>, (Sha256dHash, Vec<TxOut>)) {
1450 // Most secp and related errors trying to create keys means we have no hope of constructing
1451 // a spend transaction...so we return no transactions to broadcast
1452 let mut claimable_outpoints = Vec::new();
1453 let mut watch_outputs = Vec::new();
1455 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1456 let per_commitment_option = self.remote_claimable_outpoints.get(&commitment_txid);
1458 macro_rules! ignore_error {
1459 ( $thing : expr ) => {
1462 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs))
1467 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);
1468 if commitment_number >= self.get_min_seen_secret() {
1469 let secret = self.get_secret(commitment_number).unwrap();
1470 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1471 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1472 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.onchain_detection.keys.pubkeys().revocation_basepoint));
1473 let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &self.onchain_detection.keys.revocation_base_key()));
1474 let b_htlc_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &self.onchain_detection.keys.pubkeys().htlc_basepoint));
1475 let local_payment_key = ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, &per_commitment_point, &self.onchain_detection.keys.payment_base_key()));
1476 let delayed_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key), &self.their_delayed_payment_base_key.unwrap()));
1477 let a_htlc_key = match self.their_htlc_base_key {
1478 None => return (claimable_outpoints, (commitment_txid, watch_outputs)),
1479 Some(their_htlc_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key), &their_htlc_base_key)),
1482 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.our_to_self_delay, &delayed_key);
1483 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1485 self.broadcasted_remote_payment_script = {
1486 // Note that the Network here is ignored as we immediately drop the address for the
1487 // script_pubkey version
1488 let payment_hash160 = Hash160::hash(&PublicKey::from_secret_key(&self.secp_ctx, &local_payment_key).serialize());
1489 Some((Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_hash160[..]).into_script(), local_payment_key))
1492 // First, process non-htlc outputs (to_local & to_remote)
1493 for (idx, outp) in tx.output.iter().enumerate() {
1494 if outp.script_pubkey == revokeable_p2wsh {
1495 let witness_data = InputMaterial::Revoked { witness_script: revokeable_redeemscript.clone(), pubkey: Some(revocation_pubkey), key: revocation_key, is_htlc: false, amount: outp.value };
1496 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});
1500 // Then, try to find revoked htlc outputs
1501 if let Some(ref per_commitment_data) = per_commitment_option {
1502 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1503 if let Some(transaction_output_index) = htlc.transaction_output_index {
1504 let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1505 if transaction_output_index as usize >= tx.output.len() ||
1506 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
1507 tx.output[transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
1508 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1510 let witness_data = InputMaterial::Revoked { witness_script: expected_script, pubkey: Some(revocation_pubkey), key: revocation_key, is_htlc: true, amount: tx.output[transaction_output_index as usize].value };
1511 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable: true, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1516 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
1517 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
1518 // We're definitely a remote commitment transaction!
1519 log_trace!(self, "Got broadcast of revoked remote commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
1520 watch_outputs.append(&mut tx.output.clone());
1521 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1523 macro_rules! check_htlc_fails {
1524 ($txid: expr, $commitment_tx: expr) => {
1525 if let Some(ref outpoints) = self.remote_claimable_outpoints.get($txid) {
1526 for &(ref htlc, ref source_option) in outpoints.iter() {
1527 if let &Some(ref source) = source_option {
1528 log_info!(self, "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), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1529 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1530 hash_map::Entry::Occupied(mut entry) => {
1531 let e = entry.get_mut();
1532 e.retain(|ref event| {
1534 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1535 return htlc_update.0 != **source
1540 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1542 hash_map::Entry::Vacant(entry) => {
1543 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1551 if let Some(ref txid) = self.onchain_detection.current_remote_commitment_txid {
1552 check_htlc_fails!(txid, "current");
1554 if let Some(ref txid) = self.onchain_detection.prev_remote_commitment_txid {
1555 check_htlc_fails!(txid, "remote");
1557 // No need to check local commitment txn, symmetric HTLCSource must be present as per-htlc data on remote commitment tx
1559 } else if let Some(per_commitment_data) = per_commitment_option {
1560 // While this isn't useful yet, there is a potential race where if a counterparty
1561 // revokes a state at the same time as the commitment transaction for that state is
1562 // confirmed, and the watchtower receives the block before the user, the user could
1563 // upload a new ChannelMonitor with the revocation secret but the watchtower has
1564 // already processed the block, resulting in the remote_commitment_txn_on_chain entry
1565 // not being generated by the above conditional. Thus, to be safe, we go ahead and
1567 watch_outputs.append(&mut tx.output.clone());
1568 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1570 log_trace!(self, "Got broadcast of non-revoked remote commitment transaction {}", commitment_txid);
1572 macro_rules! check_htlc_fails {
1573 ($txid: expr, $commitment_tx: expr, $id: tt) => {
1574 if let Some(ref latest_outpoints) = self.remote_claimable_outpoints.get($txid) {
1575 $id: for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1576 if let &Some(ref source) = source_option {
1577 // Check if the HTLC is present in the commitment transaction that was
1578 // broadcast, but not if it was below the dust limit, which we should
1579 // fail backwards immediately as there is no way for us to learn the
1580 // payment_preimage.
1581 // Note that if the dust limit were allowed to change between
1582 // commitment transactions we'd want to be check whether *any*
1583 // broadcastable commitment transaction has the HTLC in it, but it
1584 // cannot currently change after channel initialization, so we don't
1586 for &(ref broadcast_htlc, ref broadcast_source) in per_commitment_data.iter() {
1587 if broadcast_htlc.transaction_output_index.is_some() && Some(source) == broadcast_source.as_ref() {
1591 log_trace!(self, "Failing HTLC with payment_hash {} from {} remote commitment tx due to broadcast of remote commitment transaction", log_bytes!(htlc.payment_hash.0), $commitment_tx);
1592 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1593 hash_map::Entry::Occupied(mut entry) => {
1594 let e = entry.get_mut();
1595 e.retain(|ref event| {
1597 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1598 return htlc_update.0 != **source
1603 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1605 hash_map::Entry::Vacant(entry) => {
1606 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1614 if let Some(ref txid) = self.onchain_detection.current_remote_commitment_txid {
1615 check_htlc_fails!(txid, "current", 'current_loop);
1617 if let Some(ref txid) = self.onchain_detection.prev_remote_commitment_txid {
1618 check_htlc_fails!(txid, "previous", 'prev_loop);
1621 if let Some(revocation_points) = self.their_cur_revocation_points {
1622 let revocation_point_option =
1623 if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1624 else if let Some(point) = revocation_points.2.as_ref() {
1625 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1627 if let Some(revocation_point) = revocation_point_option {
1628 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &self.onchain_detection.keys.pubkeys().revocation_basepoint));
1629 let b_htlc_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &self.onchain_detection.keys.pubkeys().htlc_basepoint));
1630 let htlc_privkey = ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, revocation_point, &self.onchain_detection.keys.htlc_base_key()));
1631 let a_htlc_key = match self.their_htlc_base_key {
1632 None => return (claimable_outpoints, (commitment_txid, watch_outputs)),
1633 Some(their_htlc_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &their_htlc_base_key)),
1635 let local_payment_key = ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, revocation_point, &self.onchain_detection.keys.payment_base_key()));
1637 self.broadcasted_remote_payment_script = {
1638 // Note that the Network here is ignored as we immediately drop the address for the
1639 // script_pubkey version
1640 let payment_hash160 = Hash160::hash(&PublicKey::from_secret_key(&self.secp_ctx, &local_payment_key).serialize());
1641 Some((Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_hash160[..]).into_script(), local_payment_key))
1644 // Then, try to find htlc outputs
1645 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1646 if let Some(transaction_output_index) = htlc.transaction_output_index {
1647 let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1648 if transaction_output_index as usize >= tx.output.len() ||
1649 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
1650 tx.output[transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
1651 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1653 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
1654 let aggregable = if !htlc.offered { false } else { true };
1655 if preimage.is_some() || !htlc.offered {
1656 let witness_data = InputMaterial::RemoteHTLC { witness_script: expected_script, key: htlc_privkey, preimage, amount: htlc.amount_msat / 1000, locktime: htlc.cltv_expiry };
1657 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1664 (claimable_outpoints, (commitment_txid, watch_outputs))
1667 /// Attempts to claim a remote HTLC-Success/HTLC-Timeout's outputs using the revocation key
1668 fn check_spend_remote_htlc(&mut self, tx: &Transaction, commitment_number: u64, height: u32) -> (Vec<ClaimRequest>, Option<(Sha256dHash, Vec<TxOut>)>) {
1669 let htlc_txid = tx.txid();
1670 if tx.input.len() != 1 || tx.output.len() != 1 || tx.input[0].witness.len() != 5 {
1671 return (Vec::new(), None)
1674 macro_rules! ignore_error {
1675 ( $thing : expr ) => {
1678 Err(_) => return (Vec::new(), None)
1683 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
1684 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1685 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1686 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.onchain_detection.keys.pubkeys().revocation_basepoint));
1687 let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &self.onchain_detection.keys.revocation_base_key()));
1688 let delayed_key = match self.their_delayed_payment_base_key {
1689 None => return (Vec::new(), None),
1690 Some(their_delayed_payment_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &their_delayed_payment_base_key)),
1692 let redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.our_to_self_delay, &delayed_key);
1694 log_trace!(self, "Remote HTLC broadcast {}:{}", htlc_txid, 0);
1695 let witness_data = InputMaterial::Revoked { witness_script: redeemscript, pubkey: Some(revocation_pubkey), key: revocation_key, is_htlc: false, amount: tx.output[0].value };
1696 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 });
1697 (claimable_outpoints, Some((htlc_txid, tx.output.clone())))
1700 fn broadcast_by_local_state(&self, commitment_tx: &Transaction, local_tx: &LocalSignedTx) -> (Vec<ClaimRequest>, Vec<TxOut>, Option<(Script, SecretKey, Script)>) {
1701 let mut claim_requests = Vec::with_capacity(local_tx.htlc_outputs.len());
1702 let mut watch_outputs = Vec::with_capacity(local_tx.htlc_outputs.len());
1704 let redeemscript = chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.their_to_self_delay.unwrap(), &local_tx.delayed_payment_key);
1705 let broadcasted_local_revokable_script = if let Ok(local_delayedkey) = chan_utils::derive_private_key(&self.secp_ctx, &local_tx.per_commitment_point, self.onchain_detection.keys.delayed_payment_base_key()) {
1706 Some((redeemscript.to_v0_p2wsh(), local_delayedkey, redeemscript))
1709 for &(ref htlc, _, _) in local_tx.htlc_outputs.iter() {
1710 if let Some(transaction_output_index) = htlc.transaction_output_index {
1711 let preimage = if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) { Some(*preimage) } else { None };
1712 claim_requests.push(ClaimRequest { absolute_timelock: ::std::u32::MAX, aggregable: false, outpoint: BitcoinOutPoint { txid: local_tx.txid, vout: transaction_output_index as u32 }, witness_data: InputMaterial::LocalHTLC { preimage, amount: htlc.amount_msat / 1000 }});
1713 watch_outputs.push(commitment_tx.output[transaction_output_index as usize].clone());
1717 (claim_requests, watch_outputs, broadcasted_local_revokable_script)
1720 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1721 /// revoked using data in local_claimable_outpoints.
1722 /// Should not be used if check_spend_revoked_transaction succeeds.
1723 fn check_spend_local_transaction(&mut self, tx: &Transaction, height: u32) -> (Vec<ClaimRequest>, (Sha256dHash, Vec<TxOut>)) {
1724 let commitment_txid = tx.txid();
1725 let mut claim_requests = Vec::new();
1726 let mut watch_outputs = Vec::new();
1728 macro_rules! wait_threshold_conf {
1729 ($height: expr, $source: expr, $commitment_tx: expr, $payment_hash: expr) => {
1730 log_trace!(self, "Failing HTLC with payment_hash {} from {} local commitment tx due to broadcast of transaction, waiting confirmation (at height{})", log_bytes!($payment_hash.0), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1731 match self.onchain_events_waiting_threshold_conf.entry($height + ANTI_REORG_DELAY - 1) {
1732 hash_map::Entry::Occupied(mut entry) => {
1733 let e = entry.get_mut();
1734 e.retain(|ref event| {
1736 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1737 return htlc_update.0 != $source
1742 e.push(OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)});
1744 hash_map::Entry::Vacant(entry) => {
1745 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)}]);
1751 macro_rules! append_onchain_update {
1752 ($updates: expr) => {
1753 claim_requests = $updates.0;
1754 watch_outputs.append(&mut $updates.1);
1755 self.broadcasted_local_revokable_script = $updates.2;
1759 // HTLCs set may differ between last and previous local commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
1760 let mut is_local_tx = false;
1762 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1763 if local_tx.txid == commitment_txid {
1765 log_trace!(self, "Got latest local commitment tx broadcast, searching for available HTLCs to claim");
1766 let mut res = self.broadcast_by_local_state(tx, local_tx);
1767 append_onchain_update!(res);
1770 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1771 if local_tx.txid == commitment_txid {
1773 log_trace!(self, "Got previous local commitment tx broadcast, searching for available HTLCs to claim");
1774 let mut res = self.broadcast_by_local_state(tx, local_tx);
1775 append_onchain_update!(res);
1779 macro_rules! fail_dust_htlcs_after_threshold_conf {
1780 ($local_tx: expr) => {
1781 for &(ref htlc, _, ref source) in &$local_tx.htlc_outputs {
1782 if htlc.transaction_output_index.is_none() {
1783 if let &Some(ref source) = source {
1784 wait_threshold_conf!(height, source.clone(), "lastest", htlc.payment_hash.clone());
1792 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1793 fail_dust_htlcs_after_threshold_conf!(local_tx);
1795 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1796 fail_dust_htlcs_after_threshold_conf!(local_tx);
1800 (claim_requests, (commitment_txid, watch_outputs))
1803 /// Used by ChannelManager deserialization to broadcast the latest local state if its copy of
1804 /// the Channel was out-of-date. You may use it to get a broadcastable local toxic tx in case of
1805 /// fallen-behind, i.e when receiving a channel_reestablish with a proof that our remote side knows
1806 /// a higher revocation secret than the local commitment number we are aware of. Broadcasting these
1807 /// transactions are UNSAFE, as they allow remote side to punish you. Nevertheless you may want to
1808 /// broadcast them if remote don't close channel with his higher commitment transaction after a
1809 /// substantial amount of time (a month or even a year) to get back funds. Best may be to contact
1810 /// out-of-band the other node operator to coordinate with him if option is available to you.
1811 /// In any-case, choice is up to the user.
1812 pub fn get_latest_local_commitment_txn(&mut self) -> Vec<Transaction> {
1813 log_trace!(self, "Getting signed latest local commitment transaction!");
1814 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_local_tx(self.channel_value_satoshis.unwrap()) {
1815 let txid = commitment_tx.txid();
1816 let mut res = vec![commitment_tx];
1817 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1818 for htlc in local_tx.htlc_outputs.iter() {
1819 if let Some(htlc_index) = htlc.0.transaction_output_index {
1820 let preimage = if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(*preimage) } else { None };
1821 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(txid, htlc_index, preimage) {
1826 // 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.
1827 // The data will be re-generated and tracked in check_spend_local_transaction if we get a confirmation.
1834 /// Unsafe test-only version of get_latest_local_commitment_txn used by our test framework
1835 /// to bypass LocalCommitmentTransaction state update lockdown after signature and generate
1836 /// revoked commitment transaction.
1838 pub fn unsafe_get_latest_local_commitment_txn(&mut self) -> Vec<Transaction> {
1839 log_trace!(self, "Getting signed copy of latest local commitment transaction!");
1840 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_copy_local_tx(self.channel_value_satoshis.unwrap()) {
1841 let txid = commitment_tx.txid();
1842 let mut res = vec![commitment_tx];
1843 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1844 for htlc in local_tx.htlc_outputs.iter() {
1845 if let Some(htlc_index) = htlc.0.transaction_output_index {
1846 let preimage = if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(*preimage) } else { None };
1847 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(txid, htlc_index, preimage) {
1858 /// Called by SimpleManyChannelMonitor::block_connected, which implements
1859 /// ChainListener::block_connected.
1860 /// Eventually this should be pub and, roughly, implement ChainListener, however this requires
1861 /// &mut self, as well as returns new spendable outputs and outpoints to watch for spending of
1863 fn block_connected<B: Deref, F: Deref>(&mut self, txn_matched: &[&Transaction], height: u32, block_hash: &Sha256dHash, broadcaster: B, fee_estimator: F)-> Vec<(Sha256dHash, Vec<TxOut>)>
1864 where B::Target: BroadcasterInterface,
1865 F::Target: FeeEstimator
1867 for tx in txn_matched {
1868 let mut output_val = 0;
1869 for out in tx.output.iter() {
1870 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1871 output_val += out.value;
1872 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1876 log_trace!(self, "Block {} at height {} connected with {} txn matched", block_hash, height, txn_matched.len());
1877 let mut watch_outputs = Vec::new();
1878 let mut claimable_outpoints = Vec::new();
1879 for tx in txn_matched {
1880 if tx.input.len() == 1 {
1881 // Assuming our keys were not leaked (in which case we're screwed no matter what),
1882 // commitment transactions and HTLC transactions will all only ever have one input,
1883 // which is an easy way to filter out any potential non-matching txn for lazy
1885 let prevout = &tx.input[0].previous_output;
1886 let funding_txo = self.onchain_detection.funding_info.clone();
1887 if funding_txo.is_none() || (prevout.txid == funding_txo.as_ref().unwrap().0.txid && prevout.vout == funding_txo.as_ref().unwrap().0.index as u32) {
1888 if (tx.input[0].sequence >> 8*3) as u8 == 0x80 && (tx.lock_time >> 8*3) as u8 == 0x20 {
1889 let (mut new_outpoints, new_outputs) = self.check_spend_remote_transaction(&tx, height);
1890 if !new_outputs.1.is_empty() {
1891 watch_outputs.push(new_outputs);
1893 if new_outpoints.is_empty() {
1894 let (mut new_outpoints, new_outputs) = self.check_spend_local_transaction(&tx, height);
1895 if !new_outputs.1.is_empty() {
1896 watch_outputs.push(new_outputs);
1898 claimable_outpoints.append(&mut new_outpoints);
1900 claimable_outpoints.append(&mut new_outpoints);
1903 if let Some(&(commitment_number, _)) = self.remote_commitment_txn_on_chain.get(&prevout.txid) {
1904 let (mut new_outpoints, new_outputs_option) = self.check_spend_remote_htlc(&tx, commitment_number, height);
1905 claimable_outpoints.append(&mut new_outpoints);
1906 if let Some(new_outputs) = new_outputs_option {
1907 watch_outputs.push(new_outputs);
1912 // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
1913 // can also be resolved in a few other ways which can have more than one output. Thus,
1914 // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
1915 self.is_resolving_htlc_output(&tx, height);
1917 self.is_paying_spendable_output(&tx, height);
1919 let should_broadcast = if let Some(_) = self.current_local_signed_commitment_tx {
1920 self.would_broadcast_at_height(height)
1922 if should_broadcast {
1923 claimable_outpoints.push(ClaimRequest { absolute_timelock: height, aggregable: false, outpoint: BitcoinOutPoint { txid: self.onchain_detection.funding_info.as_ref().unwrap().0.txid.clone(), vout: self.onchain_detection.funding_info.as_ref().unwrap().0.index as u32 }, witness_data: InputMaterial::Funding { channel_value: self.channel_value_satoshis.unwrap() }});
1925 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
1926 if should_broadcast {
1927 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_local_tx(self.channel_value_satoshis.unwrap()) {
1928 let (mut new_outpoints, new_outputs, _) = self.broadcast_by_local_state(&commitment_tx, cur_local_tx);
1929 if !new_outputs.is_empty() {
1930 watch_outputs.push((cur_local_tx.txid.clone(), new_outputs));
1932 claimable_outpoints.append(&mut new_outpoints);
1936 if let Some(events) = self.onchain_events_waiting_threshold_conf.remove(&height) {
1939 OnchainEvent::HTLCUpdate { htlc_update } => {
1940 log_trace!(self, "HTLC {} failure update has got enough confirmations to be passed upstream", log_bytes!((htlc_update.1).0));
1941 self.pending_htlcs_updated.push(HTLCUpdate {
1942 payment_hash: htlc_update.1,
1943 payment_preimage: None,
1944 source: htlc_update.0,
1947 OnchainEvent::MaturingOutput { descriptor } => {
1948 log_trace!(self, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
1949 self.pending_events.push(events::Event::SpendableOutputs {
1950 outputs: vec![descriptor]
1956 self.onchain_tx_handler.block_connected(txn_matched, claimable_outpoints, height, &*broadcaster, &*fee_estimator);
1958 self.last_block_hash = block_hash.clone();
1959 for &(ref txid, ref output_scripts) in watch_outputs.iter() {
1960 self.outputs_to_watch.insert(txid.clone(), output_scripts.iter().map(|o| o.script_pubkey.clone()).collect());
1966 fn block_disconnected<B: Deref, F: Deref>(&mut self, height: u32, block_hash: &Sha256dHash, broadcaster: B, fee_estimator: F)
1967 where B::Target: BroadcasterInterface,
1968 F::Target: FeeEstimator
1970 log_trace!(self, "Block {} at height {} disconnected", block_hash, height);
1971 if let Some(_) = self.onchain_events_waiting_threshold_conf.remove(&(height + ANTI_REORG_DELAY - 1)) {
1973 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
1974 //- maturing spendable output has transaction paying us has been disconnected
1977 self.onchain_tx_handler.block_disconnected(height, broadcaster, fee_estimator);
1979 self.last_block_hash = block_hash.clone();
1982 pub(super) fn would_broadcast_at_height(&self, height: u32) -> bool {
1983 // We need to consider all HTLCs which are:
1984 // * in any unrevoked remote commitment transaction, as they could broadcast said
1985 // transactions and we'd end up in a race, or
1986 // * are in our latest local commitment transaction, as this is the thing we will
1987 // broadcast if we go on-chain.
1988 // Note that we consider HTLCs which were below dust threshold here - while they don't
1989 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
1990 // to the source, and if we don't fail the channel we will have to ensure that the next
1991 // updates that peer sends us are update_fails, failing the channel if not. It's probably
1992 // easier to just fail the channel as this case should be rare enough anyway.
1993 macro_rules! scan_commitment {
1994 ($htlcs: expr, $local_tx: expr) => {
1995 for ref htlc in $htlcs {
1996 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
1997 // chain with enough room to claim the HTLC without our counterparty being able to
1998 // time out the HTLC first.
1999 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
2000 // concern is being able to claim the corresponding inbound HTLC (on another
2001 // channel) before it expires. In fact, we don't even really care if our
2002 // counterparty here claims such an outbound HTLC after it expired as long as we
2003 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
2004 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
2005 // we give ourselves a few blocks of headroom after expiration before going
2006 // on-chain for an expired HTLC.
2007 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
2008 // from us until we've reached the point where we go on-chain with the
2009 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
2010 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
2011 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
2012 // inbound_cltv == height + CLTV_CLAIM_BUFFER
2013 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
2014 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
2015 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
2016 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
2017 // The final, above, condition is checked for statically in channelmanager
2018 // with CHECK_CLTV_EXPIRY_SANITY_2.
2019 let htlc_outbound = $local_tx == htlc.offered;
2020 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
2021 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
2022 log_info!(self, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
2029 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
2030 scan_commitment!(cur_local_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
2033 if let Some(ref txid) = self.onchain_detection.current_remote_commitment_txid {
2034 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(txid) {
2035 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2038 if let Some(ref txid) = self.onchain_detection.prev_remote_commitment_txid {
2039 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(txid) {
2040 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2047 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a local
2048 /// or remote commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
2049 fn is_resolving_htlc_output(&mut self, tx: &Transaction, height: u32) {
2050 'outer_loop: for input in &tx.input {
2051 let mut payment_data = None;
2052 let revocation_sig_claim = (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && input.witness[1].len() == 33)
2053 || (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && input.witness[1].len() == 33);
2054 let accepted_preimage_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::AcceptedHTLC);
2055 let offered_preimage_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC);
2057 macro_rules! log_claim {
2058 ($tx_info: expr, $local_tx: expr, $htlc: expr, $source_avail: expr) => {
2059 // We found the output in question, but aren't failing it backwards
2060 // as we have no corresponding source and no valid remote commitment txid
2061 // to try a weak source binding with same-hash, same-value still-valid offered HTLC.
2062 // This implies either it is an inbound HTLC or an outbound HTLC on a revoked transaction.
2063 let outbound_htlc = $local_tx == $htlc.offered;
2064 if ($local_tx && revocation_sig_claim) ||
2065 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
2066 log_error!(self, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
2067 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2068 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2069 if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back" });
2071 log_info!(self, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
2072 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2073 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2074 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
2079 macro_rules! check_htlc_valid_remote {
2080 ($remote_txid: expr, $htlc_output: expr) => {
2081 if let Some(txid) = $remote_txid {
2082 for &(ref pending_htlc, ref pending_source) in self.remote_claimable_outpoints.get(&txid).unwrap() {
2083 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
2084 if let &Some(ref source) = pending_source {
2085 log_claim!("revoked remote commitment tx", false, pending_htlc, true);
2086 payment_data = Some(((**source).clone(), $htlc_output.payment_hash));
2095 macro_rules! scan_commitment {
2096 ($htlcs: expr, $tx_info: expr, $local_tx: expr) => {
2097 for (ref htlc_output, source_option) in $htlcs {
2098 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
2099 if let Some(ref source) = source_option {
2100 log_claim!($tx_info, $local_tx, htlc_output, true);
2101 // We have a resolution of an HTLC either from one of our latest
2102 // local commitment transactions or an unrevoked remote commitment
2103 // transaction. This implies we either learned a preimage, the HTLC
2104 // has timed out, or we screwed up. In any case, we should now
2105 // resolve the source HTLC with the original sender.
2106 payment_data = Some(((*source).clone(), htlc_output.payment_hash));
2107 } else if !$local_tx {
2108 check_htlc_valid_remote!(self.onchain_detection.current_remote_commitment_txid, htlc_output);
2109 if payment_data.is_none() {
2110 check_htlc_valid_remote!(self.onchain_detection.prev_remote_commitment_txid, htlc_output);
2113 if payment_data.is_none() {
2114 log_claim!($tx_info, $local_tx, htlc_output, false);
2115 continue 'outer_loop;
2122 if let Some(ref current_local_signed_commitment_tx) = self.current_local_signed_commitment_tx {
2123 if input.previous_output.txid == current_local_signed_commitment_tx.txid {
2124 scan_commitment!(current_local_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2125 "our latest local commitment tx", true);
2128 if let Some(ref prev_local_signed_commitment_tx) = self.prev_local_signed_commitment_tx {
2129 if input.previous_output.txid == prev_local_signed_commitment_tx.txid {
2130 scan_commitment!(prev_local_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2131 "our previous local commitment tx", true);
2134 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(&input.previous_output.txid) {
2135 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
2136 "remote commitment tx", false);
2139 // Check that scan_commitment, above, decided there is some source worth relaying an
2140 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
2141 if let Some((source, payment_hash)) = payment_data {
2142 let mut payment_preimage = PaymentPreimage([0; 32]);
2143 if accepted_preimage_claim {
2144 if !self.pending_htlcs_updated.iter().any(|update| update.source == source) {
2145 payment_preimage.0.copy_from_slice(&input.witness[3]);
2146 self.pending_htlcs_updated.push(HTLCUpdate {
2148 payment_preimage: Some(payment_preimage),
2152 } else if offered_preimage_claim {
2153 if !self.pending_htlcs_updated.iter().any(|update| update.source == source) {
2154 payment_preimage.0.copy_from_slice(&input.witness[1]);
2155 self.pending_htlcs_updated.push(HTLCUpdate {
2157 payment_preimage: Some(payment_preimage),
2162 log_info!(self, "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);
2163 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2164 hash_map::Entry::Occupied(mut entry) => {
2165 let e = entry.get_mut();
2166 e.retain(|ref event| {
2168 OnchainEvent::HTLCUpdate { ref htlc_update } => {
2169 return htlc_update.0 != source
2174 e.push(OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)});
2176 hash_map::Entry::Vacant(entry) => {
2177 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)}]);
2185 /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
2186 fn is_paying_spendable_output(&mut self, tx: &Transaction, height: u32) {
2187 let mut spendable_output = None;
2188 for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
2189 if outp.script_pubkey == self.destination_script {
2190 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2191 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2192 output: outp.clone(),
2195 } else if let Some(ref broadcasted_local_revokable_script) = self.broadcasted_local_revokable_script {
2196 if broadcasted_local_revokable_script.0 == outp.script_pubkey {
2197 spendable_output = Some(SpendableOutputDescriptor::DynamicOutputP2WSH {
2198 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2199 key: broadcasted_local_revokable_script.1,
2200 witness_script: broadcasted_local_revokable_script.2.clone(),
2201 to_self_delay: self.their_to_self_delay.unwrap(),
2202 output: outp.clone(),
2206 } else if let Some(ref broadcasted_remote_payment_script) = self.broadcasted_remote_payment_script {
2207 if broadcasted_remote_payment_script.0 == outp.script_pubkey {
2208 spendable_output = Some(SpendableOutputDescriptor::DynamicOutputP2WPKH {
2209 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2210 key: broadcasted_remote_payment_script.1,
2211 output: outp.clone(),
2215 } else if outp.script_pubkey == self.shutdown_script {
2216 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2217 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2218 output: outp.clone(),
2222 if let Some(spendable_output) = spendable_output {
2223 log_trace!(self, "Maturing {} until {}", log_spendable!(spendable_output), height + ANTI_REORG_DELAY - 1);
2224 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2225 hash_map::Entry::Occupied(mut entry) => {
2226 let e = entry.get_mut();
2227 e.push(OnchainEvent::MaturingOutput { descriptor: spendable_output });
2229 hash_map::Entry::Vacant(entry) => {
2230 entry.insert(vec![OnchainEvent::MaturingOutput { descriptor: spendable_output }]);
2237 const MAX_ALLOC_SIZE: usize = 64*1024;
2239 impl<ChanSigner: ChannelKeys + Readable> ReadableArgs<Arc<Logger>> for (Sha256dHash, ChannelMonitor<ChanSigner>) {
2240 fn read<R: ::std::io::Read>(reader: &mut R, logger: Arc<Logger>) -> Result<Self, DecodeError> {
2241 macro_rules! unwrap_obj {
2245 Err(_) => return Err(DecodeError::InvalidValue),
2250 let _ver: u8 = Readable::read(reader)?;
2251 let min_ver: u8 = Readable::read(reader)?;
2252 if min_ver > SERIALIZATION_VERSION {
2253 return Err(DecodeError::UnknownVersion);
2256 let latest_update_id: u64 = Readable::read(reader)?;
2257 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
2259 let destination_script = Readable::read(reader)?;
2260 let broadcasted_local_revokable_script = match <u8 as Readable>::read(reader)? {
2262 let revokable_address = Readable::read(reader)?;
2263 let local_delayedkey = Readable::read(reader)?;
2264 let revokable_script = Readable::read(reader)?;
2265 Some((revokable_address, local_delayedkey, revokable_script))
2268 _ => return Err(DecodeError::InvalidValue),
2270 let broadcasted_remote_payment_script = match <u8 as Readable>::read(reader)? {
2272 let payment_address = Readable::read(reader)?;
2273 let payment_key = Readable::read(reader)?;
2274 Some((payment_address, payment_key))
2277 _ => return Err(DecodeError::InvalidValue),
2279 let shutdown_script = Readable::read(reader)?;
2281 let onchain_detection = {
2282 let keys = Readable::read(reader)?;
2283 // Technically this can fail and serialize fail a round-trip, but only for serialization of
2284 // barely-init'd ChannelMonitors that we can't do anything with.
2285 let outpoint = OutPoint {
2286 txid: Readable::read(reader)?,
2287 index: Readable::read(reader)?,
2289 let funding_info = Some((outpoint, Readable::read(reader)?));
2290 let current_remote_commitment_txid = Readable::read(reader)?;
2291 let prev_remote_commitment_txid = Readable::read(reader)?;
2295 current_remote_commitment_txid,
2296 prev_remote_commitment_txid,
2300 let their_htlc_base_key = Some(Readable::read(reader)?);
2301 let their_delayed_payment_base_key = Some(Readable::read(reader)?);
2302 let funding_redeemscript = Some(Readable::read(reader)?);
2303 let channel_value_satoshis = Some(Readable::read(reader)?);
2305 let their_cur_revocation_points = {
2306 let first_idx = <U48 as Readable>::read(reader)?.0;
2310 let first_point = Readable::read(reader)?;
2311 let second_point_slice: [u8; 33] = Readable::read(reader)?;
2312 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
2313 Some((first_idx, first_point, None))
2315 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
2320 let our_to_self_delay: u16 = Readable::read(reader)?;
2321 let their_to_self_delay: Option<u16> = Some(Readable::read(reader)?);
2323 let commitment_secrets = Readable::read(reader)?;
2325 macro_rules! read_htlc_in_commitment {
2328 let offered: bool = Readable::read(reader)?;
2329 let amount_msat: u64 = Readable::read(reader)?;
2330 let cltv_expiry: u32 = Readable::read(reader)?;
2331 let payment_hash: PaymentHash = Readable::read(reader)?;
2332 let transaction_output_index: Option<u32> = Readable::read(reader)?;
2334 HTLCOutputInCommitment {
2335 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
2341 let remote_claimable_outpoints_len: u64 = Readable::read(reader)?;
2342 let mut remote_claimable_outpoints = HashMap::with_capacity(cmp::min(remote_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
2343 for _ in 0..remote_claimable_outpoints_len {
2344 let txid: Sha256dHash = Readable::read(reader)?;
2345 let htlcs_count: u64 = Readable::read(reader)?;
2346 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
2347 for _ in 0..htlcs_count {
2348 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
2350 if let Some(_) = remote_claimable_outpoints.insert(txid, htlcs) {
2351 return Err(DecodeError::InvalidValue);
2355 let remote_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
2356 let mut remote_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(remote_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
2357 for _ in 0..remote_commitment_txn_on_chain_len {
2358 let txid: Sha256dHash = Readable::read(reader)?;
2359 let commitment_number = <U48 as Readable>::read(reader)?.0;
2360 let outputs_count = <u64 as Readable>::read(reader)?;
2361 let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 8));
2362 for _ in 0..outputs_count {
2363 outputs.push(Readable::read(reader)?);
2365 if let Some(_) = remote_commitment_txn_on_chain.insert(txid, (commitment_number, outputs)) {
2366 return Err(DecodeError::InvalidValue);
2370 let remote_hash_commitment_number_len: u64 = Readable::read(reader)?;
2371 let mut remote_hash_commitment_number = HashMap::with_capacity(cmp::min(remote_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
2372 for _ in 0..remote_hash_commitment_number_len {
2373 let payment_hash: PaymentHash = Readable::read(reader)?;
2374 let commitment_number = <U48 as Readable>::read(reader)?.0;
2375 if let Some(_) = remote_hash_commitment_number.insert(payment_hash, commitment_number) {
2376 return Err(DecodeError::InvalidValue);
2380 macro_rules! read_local_tx {
2383 let txid = Readable::read(reader)?;
2384 let revocation_key = Readable::read(reader)?;
2385 let a_htlc_key = Readable::read(reader)?;
2386 let b_htlc_key = Readable::read(reader)?;
2387 let delayed_payment_key = Readable::read(reader)?;
2388 let per_commitment_point = Readable::read(reader)?;
2389 let feerate_per_kw: u64 = Readable::read(reader)?;
2391 let htlcs_len: u64 = Readable::read(reader)?;
2392 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_len as usize, MAX_ALLOC_SIZE / 128));
2393 for _ in 0..htlcs_len {
2394 let htlc = read_htlc_in_commitment!();
2395 let sigs = match <u8 as Readable>::read(reader)? {
2397 1 => Some(Readable::read(reader)?),
2398 _ => return Err(DecodeError::InvalidValue),
2400 htlcs.push((htlc, sigs, Readable::read(reader)?));
2405 revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, per_commitment_point, feerate_per_kw,
2412 let prev_local_signed_commitment_tx = match <u8 as Readable>::read(reader)? {
2415 Some(read_local_tx!())
2417 _ => return Err(DecodeError::InvalidValue),
2420 let current_local_signed_commitment_tx = match <u8 as Readable>::read(reader)? {
2423 Some(read_local_tx!())
2425 _ => return Err(DecodeError::InvalidValue),
2428 let current_remote_commitment_number = <U48 as Readable>::read(reader)?.0;
2429 let current_local_commitment_number = <U48 as Readable>::read(reader)?.0;
2431 let payment_preimages_len: u64 = Readable::read(reader)?;
2432 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
2433 for _ in 0..payment_preimages_len {
2434 let preimage: PaymentPreimage = Readable::read(reader)?;
2435 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2436 if let Some(_) = payment_preimages.insert(hash, preimage) {
2437 return Err(DecodeError::InvalidValue);
2441 let pending_htlcs_updated_len: u64 = Readable::read(reader)?;
2442 let mut pending_htlcs_updated = Vec::with_capacity(cmp::min(pending_htlcs_updated_len as usize, MAX_ALLOC_SIZE / (32 + 8*3)));
2443 for _ in 0..pending_htlcs_updated_len {
2444 pending_htlcs_updated.push(Readable::read(reader)?);
2447 let pending_events_len: u64 = Readable::read(reader)?;
2448 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<events::Event>()));
2449 for _ in 0..pending_events_len {
2450 if let Some(event) = MaybeReadable::read(reader)? {
2451 pending_events.push(event);
2455 let last_block_hash: Sha256dHash = Readable::read(reader)?;
2457 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
2458 let mut onchain_events_waiting_threshold_conf = HashMap::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
2459 for _ in 0..waiting_threshold_conf_len {
2460 let height_target = Readable::read(reader)?;
2461 let events_len: u64 = Readable::read(reader)?;
2462 let mut events = Vec::with_capacity(cmp::min(events_len as usize, MAX_ALLOC_SIZE / 128));
2463 for _ in 0..events_len {
2464 let ev = match <u8 as Readable>::read(reader)? {
2466 let htlc_source = Readable::read(reader)?;
2467 let hash = Readable::read(reader)?;
2468 OnchainEvent::HTLCUpdate {
2469 htlc_update: (htlc_source, hash)
2473 let descriptor = Readable::read(reader)?;
2474 OnchainEvent::MaturingOutput {
2478 _ => return Err(DecodeError::InvalidValue),
2482 onchain_events_waiting_threshold_conf.insert(height_target, events);
2485 let outputs_to_watch_len: u64 = Readable::read(reader)?;
2486 let mut outputs_to_watch = HashMap::with_capacity(cmp::min(outputs_to_watch_len as usize, MAX_ALLOC_SIZE / (mem::size_of::<Sha256dHash>() + mem::size_of::<Vec<Script>>())));
2487 for _ in 0..outputs_to_watch_len {
2488 let txid = Readable::read(reader)?;
2489 let outputs_len: u64 = Readable::read(reader)?;
2490 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Script>()));
2491 for _ in 0..outputs_len {
2492 outputs.push(Readable::read(reader)?);
2494 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
2495 return Err(DecodeError::InvalidValue);
2498 let onchain_tx_handler = ReadableArgs::read(reader, logger.clone())?;
2500 let lockdown_from_offchain = Readable::read(reader)?;
2502 Ok((last_block_hash.clone(), ChannelMonitor {
2504 commitment_transaction_number_obscure_factor,
2507 broadcasted_local_revokable_script,
2508 broadcasted_remote_payment_script,
2512 their_htlc_base_key,
2513 their_delayed_payment_base_key,
2514 funding_redeemscript,
2515 channel_value_satoshis,
2516 their_cur_revocation_points,
2519 their_to_self_delay,
2522 remote_claimable_outpoints,
2523 remote_commitment_txn_on_chain,
2524 remote_hash_commitment_number,
2526 prev_local_signed_commitment_tx,
2527 current_local_signed_commitment_tx,
2528 current_remote_commitment_number,
2529 current_local_commitment_number,
2532 pending_htlcs_updated,
2535 onchain_events_waiting_threshold_conf,
2540 lockdown_from_offchain,
2543 secp_ctx: Secp256k1::new(),
2551 use bitcoin::blockdata::script::{Script, Builder};
2552 use bitcoin::blockdata::opcodes;
2553 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, SigHashType};
2554 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
2555 use bitcoin::util::bip143;
2556 use bitcoin_hashes::Hash;
2557 use bitcoin_hashes::sha256::Hash as Sha256;
2558 use bitcoin_hashes::sha256d::Hash as Sha256dHash;
2559 use bitcoin_hashes::hex::FromHex;
2561 use chain::transaction::OutPoint;
2562 use ln::channelmanager::{PaymentPreimage, PaymentHash};
2563 use ln::channelmonitor::ChannelMonitor;
2564 use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
2566 use ln::chan_utils::{HTLCOutputInCommitment, TxCreationKeys, LocalCommitmentTransaction};
2567 use util::test_utils::TestLogger;
2568 use secp256k1::key::{SecretKey,PublicKey};
2569 use secp256k1::Secp256k1;
2570 use rand::{thread_rng,Rng};
2572 use chain::keysinterface::InMemoryChannelKeys;
2575 fn test_prune_preimages() {
2576 let secp_ctx = Secp256k1::new();
2577 let logger = Arc::new(TestLogger::new());
2579 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
2580 macro_rules! dummy_keys {
2584 per_commitment_point: dummy_key.clone(),
2585 revocation_key: dummy_key.clone(),
2586 a_htlc_key: dummy_key.clone(),
2587 b_htlc_key: dummy_key.clone(),
2588 a_delayed_payment_key: dummy_key.clone(),
2589 b_payment_key: dummy_key.clone(),
2594 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2596 let mut preimages = Vec::new();
2598 let mut rng = thread_rng();
2600 let mut preimage = PaymentPreimage([0; 32]);
2601 rng.fill_bytes(&mut preimage.0[..]);
2602 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2603 preimages.push((preimage, hash));
2607 macro_rules! preimages_slice_to_htlc_outputs {
2608 ($preimages_slice: expr) => {
2610 let mut res = Vec::new();
2611 for (idx, preimage) in $preimages_slice.iter().enumerate() {
2612 res.push((HTLCOutputInCommitment {
2616 payment_hash: preimage.1.clone(),
2617 transaction_output_index: Some(idx as u32),
2624 macro_rules! preimages_to_local_htlcs {
2625 ($preimages_slice: expr) => {
2627 let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2628 let res: Vec<_> = inp.drain(..).map(|e| { (e.0, None, e.1) }).collect();
2634 macro_rules! test_preimages_exist {
2635 ($preimages_slice: expr, $monitor: expr) => {
2636 for preimage in $preimages_slice {
2637 assert!($monitor.payment_preimages.contains_key(&preimage.1));
2642 let keys = InMemoryChannelKeys::new(
2644 SecretKey::from_slice(&[41; 32]).unwrap(),
2645 SecretKey::from_slice(&[41; 32]).unwrap(),
2646 SecretKey::from_slice(&[41; 32]).unwrap(),
2647 SecretKey::from_slice(&[41; 32]).unwrap(),
2648 SecretKey::from_slice(&[41; 32]).unwrap(),
2653 // Prune with one old state and a local commitment tx holding a few overlaps with the
2655 let mut monitor = ChannelMonitor::new(keys,
2656 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()), 0, &Script::new(),
2657 (OutPoint { txid: Sha256dHash::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
2658 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
2659 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
2660 0, Script::new(), 46, 0, logger.clone());
2662 monitor.their_to_self_delay = Some(10);
2664 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..10])).unwrap();
2665 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key);
2666 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key);
2667 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key);
2668 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key);
2669 for &(ref preimage, ref hash) in preimages.iter() {
2670 monitor.provide_payment_preimage(hash, preimage);
2673 // Now provide a secret, pruning preimages 10-15
2674 let mut secret = [0; 32];
2675 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2676 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2677 assert_eq!(monitor.payment_preimages.len(), 15);
2678 test_preimages_exist!(&preimages[0..10], monitor);
2679 test_preimages_exist!(&preimages[15..20], monitor);
2681 // Now provide a further secret, pruning preimages 15-17
2682 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2683 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2684 assert_eq!(monitor.payment_preimages.len(), 13);
2685 test_preimages_exist!(&preimages[0..10], monitor);
2686 test_preimages_exist!(&preimages[17..20], monitor);
2688 // Now update local commitment tx info, pruning only element 18 as we still care about the
2689 // previous commitment tx's preimages too
2690 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..5])).unwrap();
2691 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2692 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2693 assert_eq!(monitor.payment_preimages.len(), 12);
2694 test_preimages_exist!(&preimages[0..10], monitor);
2695 test_preimages_exist!(&preimages[18..20], monitor);
2697 // But if we do it again, we'll prune 5-10
2698 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..3])).unwrap();
2699 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2700 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2701 assert_eq!(monitor.payment_preimages.len(), 5);
2702 test_preimages_exist!(&preimages[0..5], monitor);
2706 fn test_claim_txn_weight_computation() {
2707 // We test Claim txn weight, knowing that we want expected weigth and
2708 // not actual case to avoid sigs and time-lock delays hell variances.
2710 let secp_ctx = Secp256k1::new();
2711 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
2712 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
2713 let mut sum_actual_sigs = 0;
2715 macro_rules! sign_input {
2716 ($sighash_parts: expr, $input: expr, $idx: expr, $amount: expr, $input_type: expr, $sum_actual_sigs: expr) => {
2717 let htlc = HTLCOutputInCommitment {
2718 offered: if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::OfferedHTLC { true } else { false },
2720 cltv_expiry: 2 << 16,
2721 payment_hash: PaymentHash([1; 32]),
2722 transaction_output_index: Some($idx),
2724 let redeem_script = if *$input_type == InputDescriptors::RevokedOutput { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &pubkey, &pubkey, &pubkey) };
2725 let sighash = hash_to_message!(&$sighash_parts.sighash_all(&$input, &redeem_script, $amount)[..]);
2726 let sig = secp_ctx.sign(&sighash, &privkey);
2727 $input.witness.push(sig.serialize_der().to_vec());
2728 $input.witness[0].push(SigHashType::All as u8);
2729 sum_actual_sigs += $input.witness[0].len();
2730 if *$input_type == InputDescriptors::RevokedOutput {
2731 $input.witness.push(vec!(1));
2732 } else if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::RevokedReceivedHTLC {
2733 $input.witness.push(pubkey.clone().serialize().to_vec());
2734 } else if *$input_type == InputDescriptors::ReceivedHTLC {
2735 $input.witness.push(vec![0]);
2737 $input.witness.push(PaymentPreimage([1; 32]).0.to_vec());
2739 $input.witness.push(redeem_script.into_bytes());
2740 println!("witness[0] {}", $input.witness[0].len());
2741 println!("witness[1] {}", $input.witness[1].len());
2742 println!("witness[2] {}", $input.witness[2].len());
2746 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
2747 let txid = Sha256dHash::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
2749 // Justice tx with 1 to_local, 2 revoked offered HTLCs, 1 revoked received HTLCs
2750 let mut claim_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2752 claim_tx.input.push(TxIn {
2753 previous_output: BitcoinOutPoint {
2757 script_sig: Script::new(),
2758 sequence: 0xfffffffd,
2759 witness: Vec::new(),
2762 claim_tx.output.push(TxOut {
2763 script_pubkey: script_pubkey.clone(),
2766 let base_weight = claim_tx.get_weight();
2767 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2768 let inputs_des = vec![InputDescriptors::RevokedOutput, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedReceivedHTLC];
2769 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2770 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2772 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));
2774 // Claim tx with 1 offered HTLCs, 3 received HTLCs
2775 claim_tx.input.clear();
2776 sum_actual_sigs = 0;
2778 claim_tx.input.push(TxIn {
2779 previous_output: BitcoinOutPoint {
2783 script_sig: Script::new(),
2784 sequence: 0xfffffffd,
2785 witness: Vec::new(),
2788 let base_weight = claim_tx.get_weight();
2789 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2790 let inputs_des = vec![InputDescriptors::OfferedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC];
2791 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2792 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2794 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));
2796 // Justice tx with 1 revoked HTLC-Success tx output
2797 claim_tx.input.clear();
2798 sum_actual_sigs = 0;
2799 claim_tx.input.push(TxIn {
2800 previous_output: BitcoinOutPoint {
2804 script_sig: Script::new(),
2805 sequence: 0xfffffffd,
2806 witness: Vec::new(),
2808 let base_weight = claim_tx.get_weight();
2809 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2810 let inputs_des = vec![InputDescriptors::RevokedOutput];
2811 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2812 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2814 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));
2817 // Further testing is done in the ChannelManager integration tests.