1 //! The logic to monitor for on-chain transactions and create the relevant claim responses lives
4 //! ChannelMonitor objects are generated by ChannelManager in response to relevant
5 //! messages/actions, and MUST be persisted to disk (and, preferably, remotely) before progress can
6 //! be made in responding to certain messages, see ManyChannelMonitor for more.
8 //! Note that ChannelMonitors are an important part of the lightning trust model and a copy of the
9 //! latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date
10 //! ChannelMonitors should do so). Thus, if you're building rust-lightning into an HSM or other
11 //! security-domain-separated system design, you should consider having multiple paths for
12 //! ChannelMonitors to get out of the HSM and onto monitoring devices.
14 use bitcoin::blockdata::block::BlockHeader;
15 use bitcoin::blockdata::transaction::{TxOut,Transaction};
16 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
17 use bitcoin::blockdata::script::{Script, Builder};
18 use bitcoin::blockdata::opcodes;
19 use bitcoin::consensus::encode;
20 use bitcoin::util::hash::BitcoinHash;
22 use bitcoin::hashes::Hash;
23 use bitcoin::hashes::sha256::Hash as Sha256;
24 use bitcoin::hash_types::{Txid, BlockHash, WPubkeyHash};
26 use bitcoin::secp256k1::{Secp256k1,Signature};
27 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
28 use bitcoin::secp256k1;
30 use ln::msgs::DecodeError;
32 use ln::chan_utils::{CounterpartyCommitmentSecrets, HTLCOutputInCommitment, LocalCommitmentTransaction, HTLCType};
33 use ln::channelmanager::{HTLCSource, PaymentPreimage, PaymentHash};
34 use ln::onchaintx::OnchainTxHandler;
35 use chain::chaininterface::{ChainListener, ChainWatchInterface, BroadcasterInterface, FeeEstimator};
36 use chain::transaction::OutPoint;
37 use chain::keysinterface::{SpendableOutputDescriptor, ChannelKeys};
38 use util::logger::Logger;
39 use util::ser::{ReadableArgs, Readable, MaybeReadable, Writer, Writeable, U48};
40 use util::{byte_utils, events};
42 use std::collections::{HashMap, hash_map};
43 use std::sync::{Arc,Mutex};
44 use std::{hash,cmp, mem};
47 /// An update generated by the underlying Channel itself which contains some new information the
48 /// ChannelMonitor should be made aware of.
49 #[cfg_attr(test, derive(PartialEq))]
52 pub struct ChannelMonitorUpdate {
53 pub(super) updates: Vec<ChannelMonitorUpdateStep>,
54 /// The sequence number of this update. Updates *must* be replayed in-order according to this
55 /// sequence number (and updates may panic if they are not). The update_id values are strictly
56 /// increasing and increase by one for each new update.
58 /// This sequence number is also used to track up to which points updates which returned
59 /// ChannelMonitorUpdateErr::TemporaryFailure have been applied to all copies of a given
60 /// ChannelMonitor when ChannelManager::channel_monitor_updated is called.
64 impl Writeable for ChannelMonitorUpdate {
65 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
66 self.update_id.write(w)?;
67 (self.updates.len() as u64).write(w)?;
68 for update_step in self.updates.iter() {
69 update_step.write(w)?;
74 impl Readable for ChannelMonitorUpdate {
75 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
76 let update_id: u64 = Readable::read(r)?;
77 let len: u64 = Readable::read(r)?;
78 let mut updates = Vec::with_capacity(cmp::min(len as usize, MAX_ALLOC_SIZE / ::std::mem::size_of::<ChannelMonitorUpdateStep>()));
80 updates.push(Readable::read(r)?);
82 Ok(Self { update_id, updates })
86 /// An error enum representing a failure to persist a channel monitor update.
88 pub enum ChannelMonitorUpdateErr {
89 /// Used to indicate a temporary failure (eg connection to a watchtower or remote backup of
90 /// our state failed, but is expected to succeed at some point in the future).
92 /// Such a failure will "freeze" a channel, preventing us from revoking old states or
93 /// submitting new commitment transactions to the remote party. Once the update(s) which failed
94 /// have been successfully applied, ChannelManager::channel_monitor_updated can be used to
95 /// restore the channel to an operational state.
97 /// Note that a given ChannelManager will *never* re-generate a given ChannelMonitorUpdate. If
98 /// you return a TemporaryFailure you must ensure that it is written to disk safely before
99 /// writing out the latest ChannelManager state.
101 /// Even when a channel has been "frozen" updates to the ChannelMonitor can continue to occur
102 /// (eg if an inbound HTLC which we forwarded was claimed upstream resulting in us attempting
103 /// to claim it on this channel) and those updates must be applied wherever they can be. At
104 /// least one such updated ChannelMonitor must be persisted otherwise PermanentFailure should
105 /// be returned to get things on-chain ASAP using only the in-memory copy. Obviously updates to
106 /// the channel which would invalidate previous ChannelMonitors are not made when a channel has
109 /// Note that even if updates made after TemporaryFailure succeed you must still call
110 /// channel_monitor_updated to ensure you have the latest monitor and re-enable normal channel
113 /// Note that the update being processed here will not be replayed for you when you call
114 /// ChannelManager::channel_monitor_updated, so you must store the update itself along
115 /// with the persisted ChannelMonitor on your own local disk prior to returning a
116 /// TemporaryFailure. You may, of course, employ a journaling approach, storing only the
117 /// ChannelMonitorUpdate on disk without updating the monitor itself, replaying the journal at
120 /// For deployments where a copy of ChannelMonitors and other local state are backed up in a
121 /// remote location (with local copies persisted immediately), it is anticipated that all
122 /// updates will return TemporaryFailure until the remote copies could be updated.
124 /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
125 /// different watchtower and cannot update with all watchtowers that were previously informed
126 /// of this channel). This will force-close the channel in question (which will generate one
127 /// final ChannelMonitorUpdate which must be delivered to at least one ChannelMonitor copy).
129 /// Should also be used to indicate a failure to update the local persisted copy of the channel
134 /// General Err type for ChannelMonitor actions. Generally, this implies that the data provided is
135 /// inconsistent with the ChannelMonitor being called. eg for ChannelMonitor::update_monitor this
136 /// means you tried to update a monitor for a different channel or the ChannelMonitorUpdate was
138 /// Contains a human-readable error message.
140 pub struct MonitorUpdateError(pub &'static str);
142 /// Simple structure send back by ManyChannelMonitor in case of HTLC detected onchain from a
143 /// forward channel and from which info are needed to update HTLC in a backward channel.
144 #[derive(Clone, PartialEq)]
145 pub struct HTLCUpdate {
146 pub(super) payment_hash: PaymentHash,
147 pub(super) payment_preimage: Option<PaymentPreimage>,
148 pub(super) source: HTLCSource
150 impl_writeable!(HTLCUpdate, 0, { payment_hash, payment_preimage, source });
152 /// Simple trait indicating ability to track a set of ChannelMonitors and multiplex events between
153 /// them. Generally should be implemented by keeping a local SimpleManyChannelMonitor and passing
154 /// events to it, while also taking any add/update_monitor events and passing them to some remote
157 /// In general, you must always have at least one local copy in memory, which must never fail to
158 /// update (as it is responsible for broadcasting the latest state in case the channel is closed),
159 /// and then persist it to various on-disk locations. If, for some reason, the in-memory copy fails
160 /// to update (eg out-of-memory or some other condition), you must immediately shut down without
161 /// taking any further action such as writing the current state to disk. This should likely be
162 /// accomplished via panic!() or abort().
164 /// Note that any updates to a channel's monitor *must* be applied to each instance of the
165 /// channel's monitor everywhere (including remote watchtowers) *before* this function returns. If
166 /// an update occurs and a remote watchtower is left with old state, it may broadcast transactions
167 /// which we have revoked, allowing our counterparty to claim all funds in the channel!
169 /// User needs to notify implementors of ManyChannelMonitor when a new block is connected or
170 /// disconnected using their `block_connected` and `block_disconnected` methods. However, rather
171 /// than calling these methods directly, the user should register implementors as listeners to the
172 /// BlockNotifier and call the BlockNotifier's `block_(dis)connected` methods, which will notify
173 /// all registered listeners in one go.
174 pub trait ManyChannelMonitor<ChanSigner: ChannelKeys>: Send + Sync {
175 /// Adds a monitor for the given `funding_txo`.
177 /// Implementer must also ensure that the funding_txo txid *and* outpoint are registered with
178 /// any relevant ChainWatchInterfaces such that the provided monitor receives block_connected
179 /// callbacks with the funding transaction, or any spends of it.
181 /// Further, the implementer must also ensure that each output returned in
182 /// monitor.get_outputs_to_watch() is registered to ensure that the provided monitor learns about
183 /// any spends of any of the outputs.
185 /// Any spends of outputs which should have been registered which aren't passed to
186 /// ChannelMonitors via block_connected may result in FUNDS LOSS.
187 fn add_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor<ChanSigner>) -> Result<(), ChannelMonitorUpdateErr>;
189 /// Updates a monitor for the given `funding_txo`.
191 /// Implementer must also ensure that the funding_txo txid *and* outpoint are registered with
192 /// any relevant ChainWatchInterfaces such that the provided monitor receives block_connected
193 /// callbacks with the funding transaction, or any spends of it.
195 /// Further, the implementer must also ensure that each output returned in
196 /// monitor.get_watch_outputs() is registered to ensure that the provided monitor learns about
197 /// any spends of any of the outputs.
199 /// Any spends of outputs which should have been registered which aren't passed to
200 /// ChannelMonitors via block_connected may result in FUNDS LOSS.
201 fn update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr>;
203 /// Used by ChannelManager to get list of HTLC resolved onchain and which needed to be updated
204 /// with success or failure.
206 /// You should probably just call through to
207 /// ChannelMonitor::get_and_clear_pending_htlcs_updated() for each ChannelMonitor and return
209 fn get_and_clear_pending_htlcs_updated(&self) -> Vec<HTLCUpdate>;
212 /// A simple implementation of a ManyChannelMonitor and ChainListener. Can be used to create a
213 /// watchtower or watch our own channels.
215 /// Note that you must provide your own key by which to refer to channels.
217 /// If you're accepting remote monitors (ie are implementing a watchtower), you must verify that
218 /// users cannot overwrite a given channel by providing a duplicate key. ie you should probably
219 /// index by a PublicKey which is required to sign any updates.
221 /// If you're using this for local monitoring of your own channels, you probably want to use
222 /// `OutPoint` as the key, which will give you a ManyChannelMonitor implementation.
223 pub struct SimpleManyChannelMonitor<Key, ChanSigner: ChannelKeys, T: Deref, F: Deref>
224 where T::Target: BroadcasterInterface,
225 F::Target: FeeEstimator
227 #[cfg(test)] // Used in ChannelManager tests to manipulate channels directly
228 pub monitors: Mutex<HashMap<Key, ChannelMonitor<ChanSigner>>>,
230 monitors: Mutex<HashMap<Key, ChannelMonitor<ChanSigner>>>,
231 chain_monitor: Arc<ChainWatchInterface>,
237 impl<'a, Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys, T: Deref + Sync + Send, F: Deref + Sync + Send>
238 ChainListener for SimpleManyChannelMonitor<Key, ChanSigner, T, F>
239 where T::Target: BroadcasterInterface,
240 F::Target: FeeEstimator
242 fn block_connected(&self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], _indexes_of_txn_matched: &[u32]) {
243 let block_hash = header.bitcoin_hash();
245 let mut monitors = self.monitors.lock().unwrap();
246 for monitor in monitors.values_mut() {
247 let txn_outputs = monitor.block_connected(txn_matched, height, &block_hash, &*self.broadcaster, &*self.fee_estimator);
249 for (ref txid, ref outputs) in txn_outputs {
250 for (idx, output) in outputs.iter().enumerate() {
251 self.chain_monitor.install_watch_outpoint((txid.clone(), idx as u32), &output.script_pubkey);
258 fn block_disconnected(&self, header: &BlockHeader, disconnected_height: u32) {
259 let block_hash = header.bitcoin_hash();
260 let mut monitors = self.monitors.lock().unwrap();
261 for monitor in monitors.values_mut() {
262 monitor.block_disconnected(disconnected_height, &block_hash, &*self.broadcaster, &*self.fee_estimator);
267 impl<Key : Send + cmp::Eq + hash::Hash + 'static, ChanSigner: ChannelKeys, T: Deref, F: Deref> SimpleManyChannelMonitor<Key, ChanSigner, T, F>
268 where T::Target: BroadcasterInterface,
269 F::Target: FeeEstimator
271 /// Creates a new object which can be used to monitor several channels given the chain
272 /// interface with which to register to receive notifications.
273 pub fn new(chain_monitor: Arc<ChainWatchInterface>, broadcaster: T, logger: Arc<Logger>, feeest: F) -> SimpleManyChannelMonitor<Key, ChanSigner, T, F> {
274 let res = SimpleManyChannelMonitor {
275 monitors: Mutex::new(HashMap::new()),
279 fee_estimator: feeest,
285 /// Adds or updates the monitor which monitors the channel referred to by the given key.
286 pub fn add_monitor_by_key(&self, key: Key, monitor: ChannelMonitor<ChanSigner>) -> Result<(), MonitorUpdateError> {
287 let mut monitors = self.monitors.lock().unwrap();
288 let entry = match monitors.entry(key) {
289 hash_map::Entry::Occupied(_) => return Err(MonitorUpdateError("Channel monitor for given key is already present")),
290 hash_map::Entry::Vacant(e) => e,
292 log_trace!(self, "Got new Channel Monitor for channel {}", log_bytes!(monitor.funding_info.0.to_channel_id()[..]));
293 self.chain_monitor.install_watch_tx(&monitor.funding_info.0.txid, &monitor.funding_info.1);
294 self.chain_monitor.install_watch_outpoint((monitor.funding_info.0.txid, monitor.funding_info.0.index as u32), &monitor.funding_info.1);
295 for (txid, outputs) in monitor.get_outputs_to_watch().iter() {
296 for (idx, script) in outputs.iter().enumerate() {
297 self.chain_monitor.install_watch_outpoint((*txid, idx as u32), script);
300 entry.insert(monitor);
304 /// Updates the monitor which monitors the channel referred to by the given key.
305 pub fn update_monitor_by_key(&self, key: Key, update: ChannelMonitorUpdate) -> Result<(), MonitorUpdateError> {
306 let mut monitors = self.monitors.lock().unwrap();
307 match monitors.get_mut(&key) {
308 Some(orig_monitor) => {
309 log_trace!(self, "Updating Channel Monitor for channel {}", log_funding_info!(orig_monitor));
310 orig_monitor.update_monitor(update, &self.broadcaster)
312 None => Err(MonitorUpdateError("No such monitor registered"))
317 impl<ChanSigner: ChannelKeys, T: Deref + Sync + Send, F: Deref + Sync + Send> ManyChannelMonitor<ChanSigner> for SimpleManyChannelMonitor<OutPoint, ChanSigner, T, F>
318 where T::Target: BroadcasterInterface,
319 F::Target: FeeEstimator
321 fn add_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor<ChanSigner>) -> Result<(), ChannelMonitorUpdateErr> {
322 match self.add_monitor_by_key(funding_txo, monitor) {
324 Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
328 fn update_monitor(&self, funding_txo: OutPoint, update: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr> {
329 match self.update_monitor_by_key(funding_txo, update) {
331 Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
335 fn get_and_clear_pending_htlcs_updated(&self) -> Vec<HTLCUpdate> {
336 let mut pending_htlcs_updated = Vec::new();
337 for chan in self.monitors.lock().unwrap().values_mut() {
338 pending_htlcs_updated.append(&mut chan.get_and_clear_pending_htlcs_updated());
340 pending_htlcs_updated
344 impl<Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys, T: Deref, F: Deref> events::EventsProvider for SimpleManyChannelMonitor<Key, ChanSigner, T, F>
345 where T::Target: BroadcasterInterface,
346 F::Target: FeeEstimator
348 fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
349 let mut pending_events = Vec::new();
350 for chan in self.monitors.lock().unwrap().values_mut() {
351 pending_events.append(&mut chan.get_and_clear_pending_events());
357 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
358 /// instead claiming it in its own individual transaction.
359 pub(crate) const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
360 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
361 /// HTLC-Success transaction.
362 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
363 /// transaction confirmed (and we use it in a few more, equivalent, places).
364 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 6;
365 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
366 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
367 /// copies of ChannelMonitors, including watchtowers). We could enforce the contract by failing
368 /// at CLTV expiration height but giving a grace period to our peer may be profitable for us if he
369 /// can provide an over-late preimage. Nevertheless, grace period has to be accounted in our
370 /// CLTV_EXPIRY_DELTA to be secure. Following this policy we may decrease the rate of channel failures
371 /// due to expiration but increase the cost of funds being locked longuer in case of failure.
372 /// This delay also cover a low-power peer being slow to process blocks and so being behind us on
373 /// accurate block height.
374 /// In case of onchain failure to be pass backward we may see the last block of ANTI_REORG_DELAY
375 /// with at worst this delay, so we are not only using this value as a mercy for them but also
376 /// us as a safeguard to delay with enough time.
377 pub(crate) const LATENCY_GRACE_PERIOD_BLOCKS: u32 = 3;
378 /// Number of blocks we wait on seeing a HTLC output being solved before we fail corresponding inbound
379 /// HTLCs. This prevents us from failing backwards and then getting a reorg resulting in us losing money.
380 /// We use also this delay to be sure we can remove our in-flight claim txn from bump candidates buffer.
381 /// It may cause spurrious generation of bumped claim txn but that's allright given the outpoint is already
382 /// solved by a previous claim tx. What we want to avoid is reorg evicting our claim tx and us not
383 /// keeping bumping another claim tx to solve the outpoint.
384 pub(crate) const ANTI_REORG_DELAY: u32 = 6;
385 /// Number of blocks before confirmation at which we fail back an un-relayed HTLC or at which we
386 /// refuse to accept a new HTLC.
388 /// This is used for a few separate purposes:
389 /// 1) if we've received an MPP HTLC to us and it expires within this many blocks and we are
390 /// waiting on additional parts (or waiting on the preimage for any HTLC from the user), we will
392 /// 2) if we receive an HTLC within this many blocks of its expiry (plus one to avoid a race
393 /// condition with the above), we will fail this HTLC without telling the user we received it,
394 /// 3) if we are waiting on a connection or a channel state update to send an HTLC to a peer, and
395 /// that HTLC expires within this many blocks, we will simply fail the HTLC instead.
397 /// (1) is all about protecting us - we need enough time to update the channel state before we hit
398 /// CLTV_CLAIM_BUFFER, at which point we'd go on chain to claim the HTLC with the preimage.
400 /// (2) is the same, but with an additional buffer to avoid accepting an HTLC which is immediately
401 /// in a race condition between the user connecting a block (which would fail it) and the user
402 /// providing us the preimage (which would claim it).
404 /// (3) is about our counterparty - we don't want to relay an HTLC to a counterparty when they may
405 /// end up force-closing the channel on us to claim it.
406 pub(crate) const HTLC_FAIL_BACK_BUFFER: u32 = CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS;
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>,
445 funding_redeemscript: Script,
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 funding_redeemscript } => {
474 writer.write_all(&[3; 1])?;
475 funding_redeemscript.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 InputMaterial::Funding {
523 funding_redeemscript: Readable::read(reader)?,
526 _ => return Err(DecodeError::InvalidValue),
532 /// ClaimRequest is a descriptor structure to communicate between detection
533 /// and reaction module. They are generated by ChannelMonitor while parsing
534 /// onchain txn leaked from a channel and handed over to OnchainTxHandler which
535 /// is responsible for opportunistic aggregation, selecting and enforcing
536 /// bumping logic, building and signing transactions.
537 pub(crate) struct ClaimRequest {
538 // Block height before which claiming is exclusive to one party,
539 // after reaching it, claiming may be contentious.
540 pub(crate) absolute_timelock: u32,
541 // Timeout tx must have nLocktime set which means aggregating multiple
542 // ones must take the higher nLocktime among them to satisfy all of them.
543 // Sadly it has few pitfalls, a) it takes longuer to get fund back b) CLTV_DELTA
544 // of a sooner-HTLC could be swallowed by the highest nLocktime of the HTLC set.
545 // Do simplify we mark them as non-aggregable.
546 pub(crate) aggregable: bool,
547 // Basic bitcoin outpoint (txid, vout)
548 pub(crate) outpoint: BitcoinOutPoint,
549 // Following outpoint type, set of data needed to generate transaction digest
550 // and satisfy witness program.
551 pub(crate) witness_data: InputMaterial
554 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
555 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
556 #[derive(Clone, PartialEq)]
558 /// HTLC output getting solved by a timeout, at maturation we pass upstream payment source information to solve
559 /// inbound HTLC in backward channel. Note, in case of preimage, we pass info to upstream without delay as we can
560 /// only win from it, so it's never an OnchainEvent
562 htlc_update: (HTLCSource, PaymentHash),
565 descriptor: SpendableOutputDescriptor,
569 const SERIALIZATION_VERSION: u8 = 1;
570 const MIN_SERIALIZATION_VERSION: u8 = 1;
572 #[cfg_attr(test, derive(PartialEq))]
574 pub(super) enum ChannelMonitorUpdateStep {
575 LatestLocalCommitmentTXInfo {
576 commitment_tx: LocalCommitmentTransaction,
577 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
579 LatestRemoteCommitmentTXInfo {
580 unsigned_commitment_tx: Transaction, // TODO: We should actually only need the txid here
581 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
582 commitment_number: u64,
583 their_revocation_point: PublicKey,
586 payment_preimage: PaymentPreimage,
592 /// Used to indicate that the no future updates will occur, and likely that the latest local
593 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
595 /// If set to false, we shouldn't broadcast the latest local commitment transaction as we
596 /// think we've fallen behind!
597 should_broadcast: bool,
601 impl Writeable for ChannelMonitorUpdateStep {
602 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
604 &ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { ref commitment_tx, ref htlc_outputs } => {
606 commitment_tx.write(w)?;
607 (htlc_outputs.len() as u64).write(w)?;
608 for &(ref output, ref signature, ref source) in htlc_outputs.iter() {
614 &ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { ref unsigned_commitment_tx, ref htlc_outputs, ref commitment_number, ref their_revocation_point } => {
616 unsigned_commitment_tx.write(w)?;
617 commitment_number.write(w)?;
618 their_revocation_point.write(w)?;
619 (htlc_outputs.len() as u64).write(w)?;
620 for &(ref output, ref source) in htlc_outputs.iter() {
622 source.as_ref().map(|b| b.as_ref()).write(w)?;
625 &ChannelMonitorUpdateStep::PaymentPreimage { ref payment_preimage } => {
627 payment_preimage.write(w)?;
629 &ChannelMonitorUpdateStep::CommitmentSecret { ref idx, ref secret } => {
634 &ChannelMonitorUpdateStep::ChannelForceClosed { ref should_broadcast } => {
636 should_broadcast.write(w)?;
642 impl Readable for ChannelMonitorUpdateStep {
643 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
644 match Readable::read(r)? {
646 Ok(ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo {
647 commitment_tx: Readable::read(r)?,
649 let len: u64 = Readable::read(r)?;
650 let mut res = Vec::new();
652 res.push((Readable::read(r)?, Readable::read(r)?, Readable::read(r)?));
659 Ok(ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo {
660 unsigned_commitment_tx: Readable::read(r)?,
661 commitment_number: Readable::read(r)?,
662 their_revocation_point: Readable::read(r)?,
664 let len: u64 = Readable::read(r)?;
665 let mut res = Vec::new();
667 res.push((Readable::read(r)?, <Option<HTLCSource> as Readable>::read(r)?.map(|o| Box::new(o))));
674 Ok(ChannelMonitorUpdateStep::PaymentPreimage {
675 payment_preimage: Readable::read(r)?,
679 Ok(ChannelMonitorUpdateStep::CommitmentSecret {
680 idx: Readable::read(r)?,
681 secret: Readable::read(r)?,
685 Ok(ChannelMonitorUpdateStep::ChannelForceClosed {
686 should_broadcast: Readable::read(r)?
689 _ => Err(DecodeError::InvalidValue),
694 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
695 /// on-chain transactions to ensure no loss of funds occurs.
697 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
698 /// information and are actively monitoring the chain.
700 /// Pending Events or updated HTLCs which have not yet been read out by
701 /// get_and_clear_pending_htlcs_updated or get_and_clear_pending_events are serialized to disk and
702 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
703 /// gotten are fully handled before re-serializing the new state.
704 pub struct ChannelMonitor<ChanSigner: ChannelKeys> {
705 latest_update_id: u64,
706 commitment_transaction_number_obscure_factor: u64,
708 destination_script: Script,
709 broadcasted_local_revokable_script: Option<(Script, SecretKey, Script)>,
710 remote_payment_script: Script,
711 shutdown_script: Script,
714 funding_info: (OutPoint, Script),
715 current_remote_commitment_txid: Option<Txid>,
716 prev_remote_commitment_txid: Option<Txid>,
718 their_htlc_base_key: PublicKey,
719 their_delayed_payment_base_key: PublicKey,
720 funding_redeemscript: Script,
721 channel_value_satoshis: u64,
722 // first is the idx of the first of the two revocation points
723 their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
725 our_to_self_delay: u16,
726 their_to_self_delay: u16,
728 commitment_secrets: CounterpartyCommitmentSecrets,
729 remote_claimable_outpoints: HashMap<Txid, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
730 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
731 /// Nor can we figure out their commitment numbers without the commitment transaction they are
732 /// spending. Thus, in order to claim them via revocation key, we track all the remote
733 /// commitment transactions which we find on-chain, mapping them to the commitment number which
734 /// can be used to derive the revocation key and claim the transactions.
735 remote_commitment_txn_on_chain: HashMap<Txid, (u64, Vec<Script>)>,
736 /// Cache used to make pruning of payment_preimages faster.
737 /// Maps payment_hash values to commitment numbers for remote transactions for non-revoked
738 /// remote transactions (ie should remain pretty small).
739 /// Serialized to disk but should generally not be sent to Watchtowers.
740 remote_hash_commitment_number: HashMap<PaymentHash, u64>,
742 // We store two local commitment transactions to avoid any race conditions where we may update
743 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
744 // various monitors for one channel being out of sync, and us broadcasting a local
745 // transaction for which we have deleted claim information on some watchtowers.
746 prev_local_signed_commitment_tx: Option<LocalSignedTx>,
747 current_local_commitment_tx: LocalSignedTx,
749 // Used just for ChannelManager to make sure it has the latest channel data during
751 current_remote_commitment_number: u64,
752 // Used just for ChannelManager to make sure it has the latest channel data during
754 current_local_commitment_number: u64,
756 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
758 pending_htlcs_updated: Vec<HTLCUpdate>,
759 pending_events: Vec<events::Event>,
761 // Used to track onchain events, i.e transactions parts of channels confirmed on chain, on which
762 // we have to take actions once they reach enough confs. Key is a block height timer, i.e we enforce
763 // actions when we receive a block with given height. Actions depend on OnchainEvent type.
764 onchain_events_waiting_threshold_conf: HashMap<u32, Vec<OnchainEvent>>,
766 // If we get serialized out and re-read, we need to make sure that the chain monitoring
767 // interface knows about the TXOs that we want to be notified of spends of. We could probably
768 // be smart and derive them from the above storage fields, but its much simpler and more
769 // Obviously Correct (tm) if we just keep track of them explicitly.
770 outputs_to_watch: HashMap<Txid, Vec<Script>>,
773 pub onchain_tx_handler: OnchainTxHandler<ChanSigner>,
775 onchain_tx_handler: OnchainTxHandler<ChanSigner>,
777 // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
778 // channel has been force-closed. After this is set, no further local commitment transaction
779 // updates may occur, and we panic!() if one is provided.
780 lockdown_from_offchain: bool,
782 // Set once we've signed a local commitment transaction and handed it over to our
783 // OnchainTxHandler. After this is set, no future updates to our local commitment transactions
784 // may occur, and we fail any such monitor updates.
785 local_tx_signed: bool,
787 // We simply modify last_block_hash in Channel's block_connected so that serialization is
788 // consistent but hopefully the users' copy handles block_connected in a consistent way.
789 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
790 // their last_block_hash from its state and not based on updated copies that didn't run through
791 // the full block_connected).
792 pub(crate) last_block_hash: BlockHash,
793 secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
797 #[cfg(any(test, feature = "fuzztarget"))]
798 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
799 /// underlying object
800 impl<ChanSigner: ChannelKeys> PartialEq for ChannelMonitor<ChanSigner> {
801 fn eq(&self, other: &Self) -> bool {
802 if self.latest_update_id != other.latest_update_id ||
803 self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
804 self.destination_script != other.destination_script ||
805 self.broadcasted_local_revokable_script != other.broadcasted_local_revokable_script ||
806 self.remote_payment_script != other.remote_payment_script ||
807 self.keys.pubkeys() != other.keys.pubkeys() ||
808 self.funding_info != other.funding_info ||
809 self.current_remote_commitment_txid != other.current_remote_commitment_txid ||
810 self.prev_remote_commitment_txid != other.prev_remote_commitment_txid ||
811 self.their_htlc_base_key != other.their_htlc_base_key ||
812 self.their_delayed_payment_base_key != other.their_delayed_payment_base_key ||
813 self.funding_redeemscript != other.funding_redeemscript ||
814 self.channel_value_satoshis != other.channel_value_satoshis ||
815 self.their_cur_revocation_points != other.their_cur_revocation_points ||
816 self.our_to_self_delay != other.our_to_self_delay ||
817 self.their_to_self_delay != other.their_to_self_delay ||
818 self.commitment_secrets != other.commitment_secrets ||
819 self.remote_claimable_outpoints != other.remote_claimable_outpoints ||
820 self.remote_commitment_txn_on_chain != other.remote_commitment_txn_on_chain ||
821 self.remote_hash_commitment_number != other.remote_hash_commitment_number ||
822 self.prev_local_signed_commitment_tx != other.prev_local_signed_commitment_tx ||
823 self.current_remote_commitment_number != other.current_remote_commitment_number ||
824 self.current_local_commitment_number != other.current_local_commitment_number ||
825 self.current_local_commitment_tx != other.current_local_commitment_tx ||
826 self.payment_preimages != other.payment_preimages ||
827 self.pending_htlcs_updated != other.pending_htlcs_updated ||
828 self.pending_events.len() != other.pending_events.len() || // We trust events to round-trip properly
829 self.onchain_events_waiting_threshold_conf != other.onchain_events_waiting_threshold_conf ||
830 self.outputs_to_watch != other.outputs_to_watch ||
831 self.lockdown_from_offchain != other.lockdown_from_offchain ||
832 self.local_tx_signed != other.local_tx_signed
841 impl<ChanSigner: ChannelKeys + Writeable> ChannelMonitor<ChanSigner> {
842 /// Writes this monitor into the given writer, suitable for writing to disk.
844 /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
845 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
846 /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
847 /// returned block hash and the the current chain and then reconnecting blocks to get to the
848 /// best chain) upon deserializing the object!
849 pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
850 //TODO: We still write out all the serialization here manually instead of using the fancy
851 //serialization framework we have, we should migrate things over to it.
852 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
853 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
855 self.latest_update_id.write(writer)?;
857 // Set in initial Channel-object creation, so should always be set by now:
858 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
860 self.destination_script.write(writer)?;
861 if let Some(ref broadcasted_local_revokable_script) = self.broadcasted_local_revokable_script {
862 writer.write_all(&[0; 1])?;
863 broadcasted_local_revokable_script.0.write(writer)?;
864 broadcasted_local_revokable_script.1.write(writer)?;
865 broadcasted_local_revokable_script.2.write(writer)?;
867 writer.write_all(&[1; 1])?;
870 self.remote_payment_script.write(writer)?;
871 self.shutdown_script.write(writer)?;
873 self.keys.write(writer)?;
874 writer.write_all(&self.funding_info.0.txid[..])?;
875 writer.write_all(&byte_utils::be16_to_array(self.funding_info.0.index))?;
876 self.funding_info.1.write(writer)?;
877 self.current_remote_commitment_txid.write(writer)?;
878 self.prev_remote_commitment_txid.write(writer)?;
880 writer.write_all(&self.their_htlc_base_key.serialize())?;
881 writer.write_all(&self.their_delayed_payment_base_key.serialize())?;
882 self.funding_redeemscript.write(writer)?;
883 self.channel_value_satoshis.write(writer)?;
885 match self.their_cur_revocation_points {
886 Some((idx, pubkey, second_option)) => {
887 writer.write_all(&byte_utils::be48_to_array(idx))?;
888 writer.write_all(&pubkey.serialize())?;
889 match second_option {
890 Some(second_pubkey) => {
891 writer.write_all(&second_pubkey.serialize())?;
894 writer.write_all(&[0; 33])?;
899 writer.write_all(&byte_utils::be48_to_array(0))?;
903 writer.write_all(&byte_utils::be16_to_array(self.our_to_self_delay))?;
904 writer.write_all(&byte_utils::be16_to_array(self.their_to_self_delay))?;
906 self.commitment_secrets.write(writer)?;
908 macro_rules! serialize_htlc_in_commitment {
909 ($htlc_output: expr) => {
910 writer.write_all(&[$htlc_output.offered as u8; 1])?;
911 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
912 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
913 writer.write_all(&$htlc_output.payment_hash.0[..])?;
914 $htlc_output.transaction_output_index.write(writer)?;
918 writer.write_all(&byte_utils::be64_to_array(self.remote_claimable_outpoints.len() as u64))?;
919 for (ref txid, ref htlc_infos) in self.remote_claimable_outpoints.iter() {
920 writer.write_all(&txid[..])?;
921 writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
922 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
923 serialize_htlc_in_commitment!(htlc_output);
924 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
928 writer.write_all(&byte_utils::be64_to_array(self.remote_commitment_txn_on_chain.len() as u64))?;
929 for (ref txid, &(commitment_number, ref txouts)) in self.remote_commitment_txn_on_chain.iter() {
930 writer.write_all(&txid[..])?;
931 writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
932 (txouts.len() as u64).write(writer)?;
933 for script in txouts.iter() {
934 script.write(writer)?;
938 writer.write_all(&byte_utils::be64_to_array(self.remote_hash_commitment_number.len() as u64))?;
939 for (ref payment_hash, commitment_number) in self.remote_hash_commitment_number.iter() {
940 writer.write_all(&payment_hash.0[..])?;
941 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
944 macro_rules! serialize_local_tx {
945 ($local_tx: expr) => {
946 $local_tx.txid.write(writer)?;
947 writer.write_all(&$local_tx.revocation_key.serialize())?;
948 writer.write_all(&$local_tx.a_htlc_key.serialize())?;
949 writer.write_all(&$local_tx.b_htlc_key.serialize())?;
950 writer.write_all(&$local_tx.delayed_payment_key.serialize())?;
951 writer.write_all(&$local_tx.per_commitment_point.serialize())?;
953 writer.write_all(&byte_utils::be64_to_array($local_tx.feerate_per_kw))?;
954 writer.write_all(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64))?;
955 for &(ref htlc_output, ref sig, ref htlc_source) in $local_tx.htlc_outputs.iter() {
956 serialize_htlc_in_commitment!(htlc_output);
957 if let &Some(ref their_sig) = sig {
959 writer.write_all(&their_sig.serialize_compact())?;
963 htlc_source.write(writer)?;
968 if let Some(ref prev_local_tx) = self.prev_local_signed_commitment_tx {
969 writer.write_all(&[1; 1])?;
970 serialize_local_tx!(prev_local_tx);
972 writer.write_all(&[0; 1])?;
975 serialize_local_tx!(self.current_local_commitment_tx);
977 writer.write_all(&byte_utils::be48_to_array(self.current_remote_commitment_number))?;
978 writer.write_all(&byte_utils::be48_to_array(self.current_local_commitment_number))?;
980 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
981 for payment_preimage in self.payment_preimages.values() {
982 writer.write_all(&payment_preimage.0[..])?;
985 writer.write_all(&byte_utils::be64_to_array(self.pending_htlcs_updated.len() as u64))?;
986 for data in self.pending_htlcs_updated.iter() {
990 writer.write_all(&byte_utils::be64_to_array(self.pending_events.len() as u64))?;
991 for event in self.pending_events.iter() {
992 event.write(writer)?;
995 self.last_block_hash.write(writer)?;
997 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_waiting_threshold_conf.len() as u64))?;
998 for (ref target, ref events) in self.onchain_events_waiting_threshold_conf.iter() {
999 writer.write_all(&byte_utils::be32_to_array(**target))?;
1000 writer.write_all(&byte_utils::be64_to_array(events.len() as u64))?;
1001 for ev in events.iter() {
1003 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1005 htlc_update.0.write(writer)?;
1006 htlc_update.1.write(writer)?;
1008 OnchainEvent::MaturingOutput { ref descriptor } => {
1010 descriptor.write(writer)?;
1016 (self.outputs_to_watch.len() as u64).write(writer)?;
1017 for (txid, output_scripts) in self.outputs_to_watch.iter() {
1018 txid.write(writer)?;
1019 (output_scripts.len() as u64).write(writer)?;
1020 for script in output_scripts.iter() {
1021 script.write(writer)?;
1024 self.onchain_tx_handler.write(writer)?;
1026 self.lockdown_from_offchain.write(writer)?;
1027 self.local_tx_signed.write(writer)?;
1033 impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
1034 pub(super) fn new(keys: ChanSigner, shutdown_pubkey: &PublicKey,
1035 our_to_self_delay: u16, destination_script: &Script, funding_info: (OutPoint, Script),
1036 their_htlc_base_key: &PublicKey, their_delayed_payment_base_key: &PublicKey,
1037 their_to_self_delay: u16, funding_redeemscript: Script, channel_value_satoshis: u64,
1038 commitment_transaction_number_obscure_factor: u64,
1039 initial_local_commitment_tx: LocalCommitmentTransaction,
1040 logger: Arc<Logger>) -> ChannelMonitor<ChanSigner> {
1042 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
1043 let our_channel_close_key_hash = WPubkeyHash::hash(&shutdown_pubkey.serialize());
1044 let shutdown_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
1045 let payment_key_hash = WPubkeyHash::hash(&keys.pubkeys().payment_point.serialize());
1046 let remote_payment_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_key_hash[..]).into_script();
1048 let mut onchain_tx_handler = OnchainTxHandler::new(destination_script.clone(), keys.clone(), their_to_self_delay, logger.clone());
1050 let local_tx_sequence = initial_local_commitment_tx.unsigned_tx.input[0].sequence as u64;
1051 let local_tx_locktime = initial_local_commitment_tx.unsigned_tx.lock_time as u64;
1052 let local_commitment_tx = LocalSignedTx {
1053 txid: initial_local_commitment_tx.txid(),
1054 revocation_key: initial_local_commitment_tx.local_keys.revocation_key,
1055 a_htlc_key: initial_local_commitment_tx.local_keys.a_htlc_key,
1056 b_htlc_key: initial_local_commitment_tx.local_keys.b_htlc_key,
1057 delayed_payment_key: initial_local_commitment_tx.local_keys.a_delayed_payment_key,
1058 per_commitment_point: initial_local_commitment_tx.local_keys.per_commitment_point,
1059 feerate_per_kw: initial_local_commitment_tx.feerate_per_kw,
1060 htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
1062 // Returning a monitor error before updating tracking points means in case of using
1063 // a concurrent watchtower implementation for same channel, if this one doesn't
1064 // reject update as we do, you MAY have the latest local valid commitment tx onchain
1065 // for which you want to spend outputs. We're NOT robust again this scenario right
1066 // now but we should consider it later.
1067 onchain_tx_handler.provide_latest_local_tx(initial_local_commitment_tx).unwrap();
1070 latest_update_id: 0,
1071 commitment_transaction_number_obscure_factor,
1073 destination_script: destination_script.clone(),
1074 broadcasted_local_revokable_script: None,
1075 remote_payment_script,
1080 current_remote_commitment_txid: None,
1081 prev_remote_commitment_txid: None,
1083 their_htlc_base_key: their_htlc_base_key.clone(),
1084 their_delayed_payment_base_key: their_delayed_payment_base_key.clone(),
1085 funding_redeemscript,
1086 channel_value_satoshis: channel_value_satoshis,
1087 their_cur_revocation_points: None,
1090 their_to_self_delay,
1092 commitment_secrets: CounterpartyCommitmentSecrets::new(),
1093 remote_claimable_outpoints: HashMap::new(),
1094 remote_commitment_txn_on_chain: HashMap::new(),
1095 remote_hash_commitment_number: HashMap::new(),
1097 prev_local_signed_commitment_tx: None,
1098 current_local_commitment_tx: local_commitment_tx,
1099 current_remote_commitment_number: 1 << 48,
1100 current_local_commitment_number: 0xffff_ffff_ffff - ((((local_tx_sequence & 0xffffff) << 3*8) | (local_tx_locktime as u64 & 0xffffff)) ^ commitment_transaction_number_obscure_factor),
1102 payment_preimages: HashMap::new(),
1103 pending_htlcs_updated: Vec::new(),
1104 pending_events: Vec::new(),
1106 onchain_events_waiting_threshold_conf: HashMap::new(),
1107 outputs_to_watch: HashMap::new(),
1111 lockdown_from_offchain: false,
1112 local_tx_signed: false,
1114 last_block_hash: Default::default(),
1115 secp_ctx: Secp256k1::new(),
1120 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
1121 /// needed by local commitment transactions HTCLs nor by remote ones. Unless we haven't already seen remote
1122 /// commitment transaction's secret, they are de facto pruned (we can use revocation key).
1123 pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
1124 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
1125 return Err(MonitorUpdateError("Previous secret did not match new one"));
1128 // Prune HTLCs from the previous remote commitment tx so we don't generate failure/fulfill
1129 // events for now-revoked/fulfilled HTLCs.
1130 if let Some(txid) = self.prev_remote_commitment_txid.take() {
1131 for &mut (_, ref mut source) in self.remote_claimable_outpoints.get_mut(&txid).unwrap() {
1136 if !self.payment_preimages.is_empty() {
1137 let cur_local_signed_commitment_tx = &self.current_local_commitment_tx;
1138 let prev_local_signed_commitment_tx = self.prev_local_signed_commitment_tx.as_ref();
1139 let min_idx = self.get_min_seen_secret();
1140 let remote_hash_commitment_number = &mut self.remote_hash_commitment_number;
1142 self.payment_preimages.retain(|&k, _| {
1143 for &(ref htlc, _, _) in cur_local_signed_commitment_tx.htlc_outputs.iter() {
1144 if k == htlc.payment_hash {
1148 if let Some(prev_local_commitment_tx) = prev_local_signed_commitment_tx {
1149 for &(ref htlc, _, _) in prev_local_commitment_tx.htlc_outputs.iter() {
1150 if k == htlc.payment_hash {
1155 let contains = if let Some(cn) = remote_hash_commitment_number.get(&k) {
1162 remote_hash_commitment_number.remove(&k);
1171 /// Informs this monitor of the latest remote (ie non-broadcastable) commitment transaction.
1172 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
1173 /// possibly future revocation/preimage information) to claim outputs where possible.
1174 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
1175 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) {
1176 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
1177 // so that a remote monitor doesn't learn anything unless there is a malicious close.
1178 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
1180 for &(ref htlc, _) in &htlc_outputs {
1181 self.remote_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
1184 let new_txid = unsigned_commitment_tx.txid();
1185 log_trace!(self, "Tracking new remote commitment transaction with txid {} at commitment number {} with {} HTLC outputs", new_txid, commitment_number, htlc_outputs.len());
1186 log_trace!(self, "New potential remote commitment transaction: {}", encode::serialize_hex(unsigned_commitment_tx));
1187 self.prev_remote_commitment_txid = self.current_remote_commitment_txid.take();
1188 self.current_remote_commitment_txid = Some(new_txid);
1189 self.remote_claimable_outpoints.insert(new_txid, htlc_outputs);
1190 self.current_remote_commitment_number = commitment_number;
1191 //TODO: Merge this into the other per-remote-transaction output storage stuff
1192 match self.their_cur_revocation_points {
1193 Some(old_points) => {
1194 if old_points.0 == commitment_number + 1 {
1195 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
1196 } else if old_points.0 == commitment_number + 2 {
1197 if let Some(old_second_point) = old_points.2 {
1198 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
1200 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1203 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1207 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1212 /// Informs this monitor of the latest local (ie broadcastable) commitment transaction. The
1213 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
1214 /// is important that any clones of this channel monitor (including remote clones) by kept
1215 /// up-to-date as our local commitment transaction is updated.
1216 /// Panics if set_their_to_self_delay has never been called.
1217 pub(super) fn provide_latest_local_commitment_tx_info(&mut self, commitment_tx: LocalCommitmentTransaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), MonitorUpdateError> {
1218 if self.local_tx_signed {
1219 return Err(MonitorUpdateError("A local commitment tx has already been signed, no new local commitment txn can be sent to our counterparty"));
1221 let txid = commitment_tx.txid();
1222 let sequence = commitment_tx.unsigned_tx.input[0].sequence as u64;
1223 let locktime = commitment_tx.unsigned_tx.lock_time as u64;
1224 let mut new_local_commitment_tx = LocalSignedTx {
1226 revocation_key: commitment_tx.local_keys.revocation_key,
1227 a_htlc_key: commitment_tx.local_keys.a_htlc_key,
1228 b_htlc_key: commitment_tx.local_keys.b_htlc_key,
1229 delayed_payment_key: commitment_tx.local_keys.a_delayed_payment_key,
1230 per_commitment_point: commitment_tx.local_keys.per_commitment_point,
1231 feerate_per_kw: commitment_tx.feerate_per_kw,
1232 htlc_outputs: htlc_outputs,
1234 // Returning a monitor error before updating tracking points means in case of using
1235 // a concurrent watchtower implementation for same channel, if this one doesn't
1236 // reject update as we do, you MAY have the latest local valid commitment tx onchain
1237 // for which you want to spend outputs. We're NOT robust again this scenario right
1238 // now but we should consider it later.
1239 if let Err(_) = self.onchain_tx_handler.provide_latest_local_tx(commitment_tx) {
1240 return Err(MonitorUpdateError("Local commitment signed has already been signed, no further update of LOCAL commitment transaction is allowed"));
1242 self.current_local_commitment_number = 0xffff_ffff_ffff - ((((sequence & 0xffffff) << 3*8) | (locktime as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
1243 mem::swap(&mut new_local_commitment_tx, &mut self.current_local_commitment_tx);
1244 self.prev_local_signed_commitment_tx = Some(new_local_commitment_tx);
1248 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
1249 /// commitment_tx_infos which contain the payment hash have been revoked.
1250 pub(super) fn provide_payment_preimage(&mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage) {
1251 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
1254 pub(super) fn broadcast_latest_local_commitment_txn<B: Deref>(&mut self, broadcaster: &B)
1255 where B::Target: BroadcasterInterface,
1257 for tx in self.get_latest_local_commitment_txn().iter() {
1258 broadcaster.broadcast_transaction(tx);
1262 /// Used in Channel to cheat wrt the update_ids since it plays games, will be removed soon!
1263 pub(super) fn update_monitor_ooo(&mut self, mut updates: ChannelMonitorUpdate) -> Result<(), MonitorUpdateError> {
1264 for update in updates.updates.drain(..) {
1266 ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { commitment_tx, htlc_outputs } => {
1267 if self.lockdown_from_offchain { panic!(); }
1268 self.provide_latest_local_commitment_tx_info(commitment_tx, htlc_outputs)?
1270 ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
1271 self.provide_latest_remote_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point),
1272 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
1273 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
1274 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
1275 self.provide_secret(idx, secret)?,
1276 ChannelMonitorUpdateStep::ChannelForceClosed { .. } => {},
1279 self.latest_update_id = updates.update_id;
1283 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
1286 /// panics if the given update is not the next update by update_id.
1287 pub fn update_monitor<B: Deref>(&mut self, mut updates: ChannelMonitorUpdate, broadcaster: &B) -> Result<(), MonitorUpdateError>
1288 where B::Target: BroadcasterInterface,
1290 if self.latest_update_id + 1 != updates.update_id {
1291 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
1293 for update in updates.updates.drain(..) {
1295 ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { commitment_tx, htlc_outputs } => {
1296 if self.lockdown_from_offchain { panic!(); }
1297 self.provide_latest_local_commitment_tx_info(commitment_tx, htlc_outputs)?
1299 ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
1300 self.provide_latest_remote_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point),
1301 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
1302 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
1303 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
1304 self.provide_secret(idx, secret)?,
1305 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
1306 self.lockdown_from_offchain = true;
1307 if should_broadcast {
1308 self.broadcast_latest_local_commitment_txn(broadcaster);
1310 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");
1315 self.latest_update_id = updates.update_id;
1319 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
1321 pub fn get_latest_update_id(&self) -> u64 {
1322 self.latest_update_id
1325 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
1326 pub fn get_funding_txo(&self) -> OutPoint {
1330 /// Gets a list of txids, with their output scripts (in the order they appear in the
1331 /// transaction), which we must learn about spends of via block_connected().
1332 pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<Script>> {
1333 &self.outputs_to_watch
1336 /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
1337 /// Generally useful when deserializing as during normal operation the return values of
1338 /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
1339 /// that the get_funding_txo outpoint and transaction must also be monitored for!).
1340 pub fn get_monitored_outpoints(&self) -> Vec<(Txid, u32, &Script)> {
1341 let mut res = Vec::with_capacity(self.remote_commitment_txn_on_chain.len() * 2);
1342 for (ref txid, &(_, ref outputs)) in self.remote_commitment_txn_on_chain.iter() {
1343 for (idx, output) in outputs.iter().enumerate() {
1344 res.push(((*txid).clone(), idx as u32, output));
1350 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1351 /// ChannelManager via ManyChannelMonitor::get_and_clear_pending_htlcs_updated().
1352 pub fn get_and_clear_pending_htlcs_updated(&mut self) -> Vec<HTLCUpdate> {
1353 let mut ret = Vec::new();
1354 mem::swap(&mut ret, &mut self.pending_htlcs_updated);
1358 /// Gets the list of pending events which were generated by previous actions, clearing the list
1361 /// This is called by ManyChannelMonitor::get_and_clear_pending_events() and is equivalent to
1362 /// EventsProvider::get_and_clear_pending_events() except that it requires &mut self as we do
1363 /// no internal locking in ChannelMonitors.
1364 pub fn get_and_clear_pending_events(&mut self) -> Vec<events::Event> {
1365 let mut ret = Vec::new();
1366 mem::swap(&mut ret, &mut self.pending_events);
1370 /// Can only fail if idx is < get_min_seen_secret
1371 pub(super) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
1372 self.commitment_secrets.get_secret(idx)
1375 pub(super) fn get_min_seen_secret(&self) -> u64 {
1376 self.commitment_secrets.get_min_seen_secret()
1379 pub(super) fn get_cur_remote_commitment_number(&self) -> u64 {
1380 self.current_remote_commitment_number
1383 pub(super) fn get_cur_local_commitment_number(&self) -> u64 {
1384 self.current_local_commitment_number
1387 /// Attempts to claim a remote commitment transaction's outputs using the revocation key and
1388 /// data in remote_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
1389 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
1390 /// HTLC-Success/HTLC-Timeout transactions.
1391 /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
1392 /// revoked remote commitment tx
1393 fn check_spend_remote_transaction(&mut self, tx: &Transaction, height: u32) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) {
1394 // Most secp and related errors trying to create keys means we have no hope of constructing
1395 // a spend transaction...so we return no transactions to broadcast
1396 let mut claimable_outpoints = Vec::new();
1397 let mut watch_outputs = Vec::new();
1399 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1400 let per_commitment_option = self.remote_claimable_outpoints.get(&commitment_txid);
1402 macro_rules! ignore_error {
1403 ( $thing : expr ) => {
1406 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs))
1411 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);
1412 if commitment_number >= self.get_min_seen_secret() {
1413 let secret = self.get_secret(commitment_number).unwrap();
1414 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1415 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1416 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.keys.pubkeys().revocation_basepoint));
1417 let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &self.keys.revocation_base_key()));
1418 let b_htlc_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &self.keys.pubkeys().htlc_basepoint));
1419 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));
1420 let a_htlc_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key), &self.their_htlc_base_key));
1422 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.our_to_self_delay, &delayed_key);
1423 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1425 // First, process non-htlc outputs (to_local & to_remote)
1426 for (idx, outp) in tx.output.iter().enumerate() {
1427 if outp.script_pubkey == revokeable_p2wsh {
1428 let witness_data = InputMaterial::Revoked { witness_script: revokeable_redeemscript.clone(), pubkey: Some(revocation_pubkey), key: revocation_key, is_htlc: false, amount: outp.value };
1429 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});
1433 // Then, try to find revoked htlc outputs
1434 if let Some(ref per_commitment_data) = per_commitment_option {
1435 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1436 if let Some(transaction_output_index) = htlc.transaction_output_index {
1437 let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1438 if transaction_output_index as usize >= tx.output.len() ||
1439 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
1440 tx.output[transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
1441 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1443 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 };
1444 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable: true, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1449 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
1450 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
1451 // We're definitely a remote commitment transaction!
1452 log_trace!(self, "Got broadcast of revoked remote commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
1453 watch_outputs.append(&mut tx.output.clone());
1454 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1456 macro_rules! check_htlc_fails {
1457 ($txid: expr, $commitment_tx: expr) => {
1458 if let Some(ref outpoints) = self.remote_claimable_outpoints.get($txid) {
1459 for &(ref htlc, ref source_option) in outpoints.iter() {
1460 if let &Some(ref source) = source_option {
1461 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), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1462 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1463 hash_map::Entry::Occupied(mut entry) => {
1464 let e = entry.get_mut();
1465 e.retain(|ref event| {
1467 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1468 return htlc_update.0 != **source
1473 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1475 hash_map::Entry::Vacant(entry) => {
1476 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1484 if let Some(ref txid) = self.current_remote_commitment_txid {
1485 check_htlc_fails!(txid, "current");
1487 if let Some(ref txid) = self.prev_remote_commitment_txid {
1488 check_htlc_fails!(txid, "remote");
1490 // No need to check local commitment txn, symmetric HTLCSource must be present as per-htlc data on remote commitment tx
1492 } else if let Some(per_commitment_data) = per_commitment_option {
1493 // While this isn't useful yet, there is a potential race where if a counterparty
1494 // revokes a state at the same time as the commitment transaction for that state is
1495 // confirmed, and the watchtower receives the block before the user, the user could
1496 // upload a new ChannelMonitor with the revocation secret but the watchtower has
1497 // already processed the block, resulting in the remote_commitment_txn_on_chain entry
1498 // not being generated by the above conditional. Thus, to be safe, we go ahead and
1500 watch_outputs.append(&mut tx.output.clone());
1501 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1503 log_trace!(self, "Got broadcast of non-revoked remote commitment transaction {}", commitment_txid);
1505 macro_rules! check_htlc_fails {
1506 ($txid: expr, $commitment_tx: expr, $id: tt) => {
1507 if let Some(ref latest_outpoints) = self.remote_claimable_outpoints.get($txid) {
1508 $id: for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1509 if let &Some(ref source) = source_option {
1510 // Check if the HTLC is present in the commitment transaction that was
1511 // broadcast, but not if it was below the dust limit, which we should
1512 // fail backwards immediately as there is no way for us to learn the
1513 // payment_preimage.
1514 // Note that if the dust limit were allowed to change between
1515 // commitment transactions we'd want to be check whether *any*
1516 // broadcastable commitment transaction has the HTLC in it, but it
1517 // cannot currently change after channel initialization, so we don't
1519 for &(ref broadcast_htlc, ref broadcast_source) in per_commitment_data.iter() {
1520 if broadcast_htlc.transaction_output_index.is_some() && Some(source) == broadcast_source.as_ref() {
1524 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);
1525 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1526 hash_map::Entry::Occupied(mut entry) => {
1527 let e = entry.get_mut();
1528 e.retain(|ref event| {
1530 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1531 return htlc_update.0 != **source
1536 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1538 hash_map::Entry::Vacant(entry) => {
1539 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1547 if let Some(ref txid) = self.current_remote_commitment_txid {
1548 check_htlc_fails!(txid, "current", 'current_loop);
1550 if let Some(ref txid) = self.prev_remote_commitment_txid {
1551 check_htlc_fails!(txid, "previous", 'prev_loop);
1554 if let Some(revocation_points) = self.their_cur_revocation_points {
1555 let revocation_point_option =
1556 if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1557 else if let Some(point) = revocation_points.2.as_ref() {
1558 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1560 if let Some(revocation_point) = revocation_point_option {
1561 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &self.keys.pubkeys().revocation_basepoint));
1562 let b_htlc_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &self.keys.pubkeys().htlc_basepoint));
1563 let htlc_privkey = ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, revocation_point, &self.keys.htlc_base_key()));
1564 let a_htlc_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &self.their_htlc_base_key));
1566 // Then, try to find htlc outputs
1567 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1568 if let Some(transaction_output_index) = htlc.transaction_output_index {
1569 let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1570 if transaction_output_index as usize >= tx.output.len() ||
1571 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
1572 tx.output[transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
1573 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1575 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
1576 let aggregable = if !htlc.offered { false } else { true };
1577 if preimage.is_some() || !htlc.offered {
1578 let witness_data = InputMaterial::RemoteHTLC { witness_script: expected_script, key: htlc_privkey, preimage, amount: htlc.amount_msat / 1000, locktime: htlc.cltv_expiry };
1579 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1586 (claimable_outpoints, (commitment_txid, watch_outputs))
1589 /// Attempts to claim a remote HTLC-Success/HTLC-Timeout's outputs using the revocation key
1590 fn check_spend_remote_htlc(&mut self, tx: &Transaction, commitment_number: u64, height: u32) -> (Vec<ClaimRequest>, Option<(Txid, Vec<TxOut>)>) {
1591 let htlc_txid = tx.txid();
1592 if tx.input.len() != 1 || tx.output.len() != 1 || tx.input[0].witness.len() != 5 {
1593 return (Vec::new(), None)
1596 macro_rules! ignore_error {
1597 ( $thing : expr ) => {
1600 Err(_) => return (Vec::new(), None)
1605 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
1606 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1607 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1608 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.keys.pubkeys().revocation_basepoint));
1609 let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &self.keys.revocation_base_key()));
1610 let delayed_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &self.their_delayed_payment_base_key));
1611 let redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.our_to_self_delay, &delayed_key);
1613 log_trace!(self, "Remote HTLC broadcast {}:{}", htlc_txid, 0);
1614 let witness_data = InputMaterial::Revoked { witness_script: redeemscript, pubkey: Some(revocation_pubkey), key: revocation_key, is_htlc: false, amount: tx.output[0].value };
1615 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 });
1616 (claimable_outpoints, Some((htlc_txid, tx.output.clone())))
1619 fn broadcast_by_local_state(&self, commitment_tx: &Transaction, local_tx: &LocalSignedTx) -> (Vec<ClaimRequest>, Vec<TxOut>, Option<(Script, SecretKey, Script)>) {
1620 let mut claim_requests = Vec::with_capacity(local_tx.htlc_outputs.len());
1621 let mut watch_outputs = Vec::with_capacity(local_tx.htlc_outputs.len());
1623 let redeemscript = chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.their_to_self_delay, &local_tx.delayed_payment_key);
1624 let broadcasted_local_revokable_script = if let Ok(local_delayedkey) = chan_utils::derive_private_key(&self.secp_ctx, &local_tx.per_commitment_point, self.keys.delayed_payment_base_key()) {
1625 Some((redeemscript.to_v0_p2wsh(), local_delayedkey, redeemscript))
1628 for &(ref htlc, _, _) in local_tx.htlc_outputs.iter() {
1629 if let Some(transaction_output_index) = htlc.transaction_output_index {
1630 claim_requests.push(ClaimRequest { absolute_timelock: ::std::u32::MAX, aggregable: false, outpoint: BitcoinOutPoint { txid: local_tx.txid, vout: transaction_output_index as u32 },
1631 witness_data: InputMaterial::LocalHTLC {
1632 preimage: if !htlc.offered {
1633 if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1634 Some(preimage.clone())
1636 // We can't build an HTLC-Success transaction without the preimage
1640 amount: htlc.amount_msat,
1642 watch_outputs.push(commitment_tx.output[transaction_output_index as usize].clone());
1646 (claim_requests, watch_outputs, broadcasted_local_revokable_script)
1649 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1650 /// revoked using data in local_claimable_outpoints.
1651 /// Should not be used if check_spend_revoked_transaction succeeds.
1652 fn check_spend_local_transaction(&mut self, tx: &Transaction, height: u32) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) {
1653 let commitment_txid = tx.txid();
1654 let mut claim_requests = Vec::new();
1655 let mut watch_outputs = Vec::new();
1657 macro_rules! wait_threshold_conf {
1658 ($height: expr, $source: expr, $commitment_tx: expr, $payment_hash: expr) => {
1659 log_trace!(self, "Failing HTLC with payment_hash {} from {} local commitment tx due to broadcast of transaction, waiting confirmation (at height{})", log_bytes!($payment_hash.0), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1660 match self.onchain_events_waiting_threshold_conf.entry($height + ANTI_REORG_DELAY - 1) {
1661 hash_map::Entry::Occupied(mut entry) => {
1662 let e = entry.get_mut();
1663 e.retain(|ref event| {
1665 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1666 return htlc_update.0 != $source
1671 e.push(OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)});
1673 hash_map::Entry::Vacant(entry) => {
1674 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)}]);
1680 macro_rules! append_onchain_update {
1681 ($updates: expr) => {
1682 claim_requests = $updates.0;
1683 watch_outputs.append(&mut $updates.1);
1684 self.broadcasted_local_revokable_script = $updates.2;
1688 // HTLCs set may differ between last and previous local commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
1689 let mut is_local_tx = false;
1691 if self.current_local_commitment_tx.txid == commitment_txid {
1693 log_trace!(self, "Got latest local commitment tx broadcast, searching for available HTLCs to claim");
1694 let mut res = self.broadcast_by_local_state(tx, &self.current_local_commitment_tx);
1695 append_onchain_update!(res);
1696 } else if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1697 if local_tx.txid == commitment_txid {
1699 log_trace!(self, "Got previous local commitment tx broadcast, searching for available HTLCs to claim");
1700 let mut res = self.broadcast_by_local_state(tx, local_tx);
1701 append_onchain_update!(res);
1705 macro_rules! fail_dust_htlcs_after_threshold_conf {
1706 ($local_tx: expr) => {
1707 for &(ref htlc, _, ref source) in &$local_tx.htlc_outputs {
1708 if htlc.transaction_output_index.is_none() {
1709 if let &Some(ref source) = source {
1710 wait_threshold_conf!(height, source.clone(), "lastest", htlc.payment_hash.clone());
1718 fail_dust_htlcs_after_threshold_conf!(self.current_local_commitment_tx);
1719 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1720 fail_dust_htlcs_after_threshold_conf!(local_tx);
1724 (claim_requests, (commitment_txid, watch_outputs))
1727 /// Used by ChannelManager deserialization to broadcast the latest local state if its copy of
1728 /// the Channel was out-of-date. You may use it to get a broadcastable local toxic tx in case of
1729 /// fallen-behind, i.e when receiving a channel_reestablish with a proof that our remote side knows
1730 /// a higher revocation secret than the local commitment number we are aware of. Broadcasting these
1731 /// transactions are UNSAFE, as they allow remote side to punish you. Nevertheless you may want to
1732 /// broadcast them if remote don't close channel with his higher commitment transaction after a
1733 /// substantial amount of time (a month or even a year) to get back funds. Best may be to contact
1734 /// out-of-band the other node operator to coordinate with him if option is available to you.
1735 /// In any-case, choice is up to the user.
1736 pub fn get_latest_local_commitment_txn(&mut self) -> Vec<Transaction> {
1737 log_trace!(self, "Getting signed latest local commitment transaction!");
1738 self.local_tx_signed = true;
1739 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_local_tx(&self.funding_redeemscript) {
1740 let txid = commitment_tx.txid();
1741 let mut res = vec![commitment_tx];
1742 for htlc in self.current_local_commitment_tx.htlc_outputs.iter() {
1743 if let Some(vout) = htlc.0.transaction_output_index {
1744 let preimage = if !htlc.0.offered {
1745 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1746 // We can't build an HTLC-Success transaction without the preimage
1750 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
1751 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1756 // 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.
1757 // The data will be re-generated and tracked in check_spend_local_transaction if we get a confirmation.
1763 /// Unsafe test-only version of get_latest_local_commitment_txn used by our test framework
1764 /// to bypass LocalCommitmentTransaction state update lockdown after signature and generate
1765 /// revoked commitment transaction.
1767 pub fn unsafe_get_latest_local_commitment_txn(&mut self) -> Vec<Transaction> {
1768 log_trace!(self, "Getting signed copy of latest local commitment transaction!");
1769 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_copy_local_tx(&self.funding_redeemscript) {
1770 let txid = commitment_tx.txid();
1771 let mut res = vec![commitment_tx];
1772 for htlc in self.current_local_commitment_tx.htlc_outputs.iter() {
1773 if let Some(vout) = htlc.0.transaction_output_index {
1774 let preimage = if !htlc.0.offered {
1775 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1776 // We can't build an HTLC-Success transaction without the preimage
1780 if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
1781 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1791 /// Called by SimpleManyChannelMonitor::block_connected, which implements
1792 /// ChainListener::block_connected.
1793 /// Eventually this should be pub and, roughly, implement ChainListener, however this requires
1794 /// &mut self, as well as returns new spendable outputs and outpoints to watch for spending of
1796 fn block_connected<B: Deref, F: Deref>(&mut self, txn_matched: &[&Transaction], height: u32, block_hash: &BlockHash, broadcaster: B, fee_estimator: F)-> Vec<(Txid, Vec<TxOut>)>
1797 where B::Target: BroadcasterInterface,
1798 F::Target: FeeEstimator
1800 for tx in txn_matched {
1801 let mut output_val = 0;
1802 for out in tx.output.iter() {
1803 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1804 output_val += out.value;
1805 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1809 log_trace!(self, "Block {} at height {} connected with {} txn matched", block_hash, height, txn_matched.len());
1810 let mut watch_outputs = Vec::new();
1811 let mut claimable_outpoints = Vec::new();
1812 for tx in txn_matched {
1813 if tx.input.len() == 1 {
1814 // Assuming our keys were not leaked (in which case we're screwed no matter what),
1815 // commitment transactions and HTLC transactions will all only ever have one input,
1816 // which is an easy way to filter out any potential non-matching txn for lazy
1818 let prevout = &tx.input[0].previous_output;
1819 if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
1820 if (tx.input[0].sequence >> 8*3) as u8 == 0x80 && (tx.lock_time >> 8*3) as u8 == 0x20 {
1821 let (mut new_outpoints, new_outputs) = self.check_spend_remote_transaction(&tx, height);
1822 if !new_outputs.1.is_empty() {
1823 watch_outputs.push(new_outputs);
1825 if new_outpoints.is_empty() {
1826 let (mut new_outpoints, new_outputs) = self.check_spend_local_transaction(&tx, height);
1827 if !new_outputs.1.is_empty() {
1828 watch_outputs.push(new_outputs);
1830 claimable_outpoints.append(&mut new_outpoints);
1832 claimable_outpoints.append(&mut new_outpoints);
1835 if let Some(&(commitment_number, _)) = self.remote_commitment_txn_on_chain.get(&prevout.txid) {
1836 let (mut new_outpoints, new_outputs_option) = self.check_spend_remote_htlc(&tx, commitment_number, height);
1837 claimable_outpoints.append(&mut new_outpoints);
1838 if let Some(new_outputs) = new_outputs_option {
1839 watch_outputs.push(new_outputs);
1844 // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
1845 // can also be resolved in a few other ways which can have more than one output. Thus,
1846 // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
1847 self.is_resolving_htlc_output(&tx, height);
1849 self.is_paying_spendable_output(&tx, height);
1851 let should_broadcast = self.would_broadcast_at_height(height);
1852 if should_broadcast {
1853 claimable_outpoints.push(ClaimRequest { absolute_timelock: height, aggregable: false, outpoint: BitcoinOutPoint { txid: self.funding_info.0.txid.clone(), vout: self.funding_info.0.index as u32 }, witness_data: InputMaterial::Funding { funding_redeemscript: self.funding_redeemscript.clone() }});
1855 if should_broadcast {
1856 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_local_tx(&self.funding_redeemscript) {
1857 let (mut new_outpoints, new_outputs, _) = self.broadcast_by_local_state(&commitment_tx, &self.current_local_commitment_tx);
1858 if !new_outputs.is_empty() {
1859 watch_outputs.push((self.current_local_commitment_tx.txid.clone(), new_outputs));
1861 claimable_outpoints.append(&mut new_outpoints);
1864 if let Some(events) = self.onchain_events_waiting_threshold_conf.remove(&height) {
1867 OnchainEvent::HTLCUpdate { htlc_update } => {
1868 log_trace!(self, "HTLC {} failure update has got enough confirmations to be passed upstream", log_bytes!((htlc_update.1).0));
1869 self.pending_htlcs_updated.push(HTLCUpdate {
1870 payment_hash: htlc_update.1,
1871 payment_preimage: None,
1872 source: htlc_update.0,
1875 OnchainEvent::MaturingOutput { descriptor } => {
1876 log_trace!(self, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
1877 self.pending_events.push(events::Event::SpendableOutputs {
1878 outputs: vec![descriptor]
1884 self.onchain_tx_handler.block_connected(txn_matched, claimable_outpoints, height, &*broadcaster, &*fee_estimator);
1886 self.last_block_hash = block_hash.clone();
1887 for &(ref txid, ref output_scripts) in watch_outputs.iter() {
1888 self.outputs_to_watch.insert(txid.clone(), output_scripts.iter().map(|o| o.script_pubkey.clone()).collect());
1894 fn block_disconnected<B: Deref, F: Deref>(&mut self, height: u32, block_hash: &BlockHash, broadcaster: B, fee_estimator: F)
1895 where B::Target: BroadcasterInterface,
1896 F::Target: FeeEstimator
1898 log_trace!(self, "Block {} at height {} disconnected", block_hash, height);
1899 if let Some(_) = self.onchain_events_waiting_threshold_conf.remove(&(height + ANTI_REORG_DELAY - 1)) {
1901 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
1902 //- maturing spendable output has transaction paying us has been disconnected
1905 self.onchain_tx_handler.block_disconnected(height, broadcaster, fee_estimator);
1907 self.last_block_hash = block_hash.clone();
1910 pub(super) fn would_broadcast_at_height(&self, height: u32) -> bool {
1911 // We need to consider all HTLCs which are:
1912 // * in any unrevoked remote commitment transaction, as they could broadcast said
1913 // transactions and we'd end up in a race, or
1914 // * are in our latest local commitment transaction, as this is the thing we will
1915 // broadcast if we go on-chain.
1916 // Note that we consider HTLCs which were below dust threshold here - while they don't
1917 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
1918 // to the source, and if we don't fail the channel we will have to ensure that the next
1919 // updates that peer sends us are update_fails, failing the channel if not. It's probably
1920 // easier to just fail the channel as this case should be rare enough anyway.
1921 macro_rules! scan_commitment {
1922 ($htlcs: expr, $local_tx: expr) => {
1923 for ref htlc in $htlcs {
1924 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
1925 // chain with enough room to claim the HTLC without our counterparty being able to
1926 // time out the HTLC first.
1927 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
1928 // concern is being able to claim the corresponding inbound HTLC (on another
1929 // channel) before it expires. In fact, we don't even really care if our
1930 // counterparty here claims such an outbound HTLC after it expired as long as we
1931 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
1932 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
1933 // we give ourselves a few blocks of headroom after expiration before going
1934 // on-chain for an expired HTLC.
1935 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
1936 // from us until we've reached the point where we go on-chain with the
1937 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
1938 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
1939 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
1940 // inbound_cltv == height + CLTV_CLAIM_BUFFER
1941 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
1942 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
1943 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
1944 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
1945 // The final, above, condition is checked for statically in channelmanager
1946 // with CHECK_CLTV_EXPIRY_SANITY_2.
1947 let htlc_outbound = $local_tx == htlc.offered;
1948 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
1949 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
1950 log_info!(self, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
1957 scan_commitment!(self.current_local_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
1959 if let Some(ref txid) = self.current_remote_commitment_txid {
1960 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(txid) {
1961 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
1964 if let Some(ref txid) = self.prev_remote_commitment_txid {
1965 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(txid) {
1966 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
1973 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a local
1974 /// or remote commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
1975 fn is_resolving_htlc_output(&mut self, tx: &Transaction, height: u32) {
1976 'outer_loop: for input in &tx.input {
1977 let mut payment_data = None;
1978 let revocation_sig_claim = (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && input.witness[1].len() == 33)
1979 || (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && input.witness[1].len() == 33);
1980 let accepted_preimage_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::AcceptedHTLC);
1981 let offered_preimage_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC);
1983 macro_rules! log_claim {
1984 ($tx_info: expr, $local_tx: expr, $htlc: expr, $source_avail: expr) => {
1985 // We found the output in question, but aren't failing it backwards
1986 // as we have no corresponding source and no valid remote commitment txid
1987 // to try a weak source binding with same-hash, same-value still-valid offered HTLC.
1988 // This implies either it is an inbound HTLC or an outbound HTLC on a revoked transaction.
1989 let outbound_htlc = $local_tx == $htlc.offered;
1990 if ($local_tx && revocation_sig_claim) ||
1991 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
1992 log_error!(self, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
1993 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
1994 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
1995 if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back" });
1997 log_info!(self, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
1998 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
1999 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2000 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
2005 macro_rules! check_htlc_valid_remote {
2006 ($remote_txid: expr, $htlc_output: expr) => {
2007 if let Some(txid) = $remote_txid {
2008 for &(ref pending_htlc, ref pending_source) in self.remote_claimable_outpoints.get(&txid).unwrap() {
2009 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
2010 if let &Some(ref source) = pending_source {
2011 log_claim!("revoked remote commitment tx", false, pending_htlc, true);
2012 payment_data = Some(((**source).clone(), $htlc_output.payment_hash));
2021 macro_rules! scan_commitment {
2022 ($htlcs: expr, $tx_info: expr, $local_tx: expr) => {
2023 for (ref htlc_output, source_option) in $htlcs {
2024 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
2025 if let Some(ref source) = source_option {
2026 log_claim!($tx_info, $local_tx, htlc_output, true);
2027 // We have a resolution of an HTLC either from one of our latest
2028 // local commitment transactions or an unrevoked remote commitment
2029 // transaction. This implies we either learned a preimage, the HTLC
2030 // has timed out, or we screwed up. In any case, we should now
2031 // resolve the source HTLC with the original sender.
2032 payment_data = Some(((*source).clone(), htlc_output.payment_hash));
2033 } else if !$local_tx {
2034 check_htlc_valid_remote!(self.current_remote_commitment_txid, htlc_output);
2035 if payment_data.is_none() {
2036 check_htlc_valid_remote!(self.prev_remote_commitment_txid, htlc_output);
2039 if payment_data.is_none() {
2040 log_claim!($tx_info, $local_tx, htlc_output, false);
2041 continue 'outer_loop;
2048 if input.previous_output.txid == self.current_local_commitment_tx.txid {
2049 scan_commitment!(self.current_local_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2050 "our latest local commitment tx", true);
2052 if let Some(ref prev_local_signed_commitment_tx) = self.prev_local_signed_commitment_tx {
2053 if input.previous_output.txid == prev_local_signed_commitment_tx.txid {
2054 scan_commitment!(prev_local_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2055 "our previous local commitment tx", true);
2058 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(&input.previous_output.txid) {
2059 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
2060 "remote commitment tx", false);
2063 // Check that scan_commitment, above, decided there is some source worth relaying an
2064 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
2065 if let Some((source, payment_hash)) = payment_data {
2066 let mut payment_preimage = PaymentPreimage([0; 32]);
2067 if accepted_preimage_claim {
2068 if !self.pending_htlcs_updated.iter().any(|update| update.source == source) {
2069 payment_preimage.0.copy_from_slice(&input.witness[3]);
2070 self.pending_htlcs_updated.push(HTLCUpdate {
2072 payment_preimage: Some(payment_preimage),
2076 } else if offered_preimage_claim {
2077 if !self.pending_htlcs_updated.iter().any(|update| update.source == source) {
2078 payment_preimage.0.copy_from_slice(&input.witness[1]);
2079 self.pending_htlcs_updated.push(HTLCUpdate {
2081 payment_preimage: Some(payment_preimage),
2086 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);
2087 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2088 hash_map::Entry::Occupied(mut entry) => {
2089 let e = entry.get_mut();
2090 e.retain(|ref event| {
2092 OnchainEvent::HTLCUpdate { ref htlc_update } => {
2093 return htlc_update.0 != source
2098 e.push(OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)});
2100 hash_map::Entry::Vacant(entry) => {
2101 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)}]);
2109 /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
2110 fn is_paying_spendable_output(&mut self, tx: &Transaction, height: u32) {
2111 let mut spendable_output = None;
2112 for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
2113 if outp.script_pubkey == self.destination_script {
2114 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2115 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2116 output: outp.clone(),
2119 } else if let Some(ref broadcasted_local_revokable_script) = self.broadcasted_local_revokable_script {
2120 if broadcasted_local_revokable_script.0 == outp.script_pubkey {
2121 spendable_output = Some(SpendableOutputDescriptor::DynamicOutputP2WSH {
2122 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2123 key: broadcasted_local_revokable_script.1,
2124 witness_script: broadcasted_local_revokable_script.2.clone(),
2125 to_self_delay: self.their_to_self_delay,
2126 output: outp.clone(),
2130 } else if self.remote_payment_script == outp.script_pubkey {
2131 spendable_output = Some(SpendableOutputDescriptor::DynamicOutputP2WPKH {
2132 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2133 key: self.keys.payment_key().clone(),
2134 output: outp.clone(),
2137 } else if outp.script_pubkey == self.shutdown_script {
2138 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2139 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2140 output: outp.clone(),
2144 if let Some(spendable_output) = spendable_output {
2145 log_trace!(self, "Maturing {} until {}", log_spendable!(spendable_output), height + ANTI_REORG_DELAY - 1);
2146 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2147 hash_map::Entry::Occupied(mut entry) => {
2148 let e = entry.get_mut();
2149 e.push(OnchainEvent::MaturingOutput { descriptor: spendable_output });
2151 hash_map::Entry::Vacant(entry) => {
2152 entry.insert(vec![OnchainEvent::MaturingOutput { descriptor: spendable_output }]);
2159 const MAX_ALLOC_SIZE: usize = 64*1024;
2161 impl<ChanSigner: ChannelKeys + Readable> ReadableArgs<Arc<Logger>> for (BlockHash, ChannelMonitor<ChanSigner>) {
2162 fn read<R: ::std::io::Read>(reader: &mut R, logger: Arc<Logger>) -> Result<Self, DecodeError> {
2163 macro_rules! unwrap_obj {
2167 Err(_) => return Err(DecodeError::InvalidValue),
2172 let _ver: u8 = Readable::read(reader)?;
2173 let min_ver: u8 = Readable::read(reader)?;
2174 if min_ver > SERIALIZATION_VERSION {
2175 return Err(DecodeError::UnknownVersion);
2178 let latest_update_id: u64 = Readable::read(reader)?;
2179 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
2181 let destination_script = Readable::read(reader)?;
2182 let broadcasted_local_revokable_script = match <u8 as Readable>::read(reader)? {
2184 let revokable_address = Readable::read(reader)?;
2185 let local_delayedkey = Readable::read(reader)?;
2186 let revokable_script = Readable::read(reader)?;
2187 Some((revokable_address, local_delayedkey, revokable_script))
2190 _ => return Err(DecodeError::InvalidValue),
2192 let remote_payment_script = Readable::read(reader)?;
2193 let shutdown_script = Readable::read(reader)?;
2195 let keys = Readable::read(reader)?;
2196 // Technically this can fail and serialize fail a round-trip, but only for serialization of
2197 // barely-init'd ChannelMonitors that we can't do anything with.
2198 let outpoint = OutPoint {
2199 txid: Readable::read(reader)?,
2200 index: Readable::read(reader)?,
2202 let funding_info = (outpoint, Readable::read(reader)?);
2203 let current_remote_commitment_txid = Readable::read(reader)?;
2204 let prev_remote_commitment_txid = Readable::read(reader)?;
2206 let their_htlc_base_key = Readable::read(reader)?;
2207 let their_delayed_payment_base_key = Readable::read(reader)?;
2208 let funding_redeemscript = Readable::read(reader)?;
2209 let channel_value_satoshis = Readable::read(reader)?;
2211 let their_cur_revocation_points = {
2212 let first_idx = <U48 as Readable>::read(reader)?.0;
2216 let first_point = Readable::read(reader)?;
2217 let second_point_slice: [u8; 33] = Readable::read(reader)?;
2218 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
2219 Some((first_idx, first_point, None))
2221 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
2226 let our_to_self_delay: u16 = Readable::read(reader)?;
2227 let their_to_self_delay: u16 = Readable::read(reader)?;
2229 let commitment_secrets = Readable::read(reader)?;
2231 macro_rules! read_htlc_in_commitment {
2234 let offered: bool = Readable::read(reader)?;
2235 let amount_msat: u64 = Readable::read(reader)?;
2236 let cltv_expiry: u32 = Readable::read(reader)?;
2237 let payment_hash: PaymentHash = Readable::read(reader)?;
2238 let transaction_output_index: Option<u32> = Readable::read(reader)?;
2240 HTLCOutputInCommitment {
2241 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
2247 let remote_claimable_outpoints_len: u64 = Readable::read(reader)?;
2248 let mut remote_claimable_outpoints = HashMap::with_capacity(cmp::min(remote_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
2249 for _ in 0..remote_claimable_outpoints_len {
2250 let txid: Txid = Readable::read(reader)?;
2251 let htlcs_count: u64 = Readable::read(reader)?;
2252 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
2253 for _ in 0..htlcs_count {
2254 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
2256 if let Some(_) = remote_claimable_outpoints.insert(txid, htlcs) {
2257 return Err(DecodeError::InvalidValue);
2261 let remote_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
2262 let mut remote_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(remote_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
2263 for _ in 0..remote_commitment_txn_on_chain_len {
2264 let txid: Txid = Readable::read(reader)?;
2265 let commitment_number = <U48 as Readable>::read(reader)?.0;
2266 let outputs_count = <u64 as Readable>::read(reader)?;
2267 let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 8));
2268 for _ in 0..outputs_count {
2269 outputs.push(Readable::read(reader)?);
2271 if let Some(_) = remote_commitment_txn_on_chain.insert(txid, (commitment_number, outputs)) {
2272 return Err(DecodeError::InvalidValue);
2276 let remote_hash_commitment_number_len: u64 = Readable::read(reader)?;
2277 let mut remote_hash_commitment_number = HashMap::with_capacity(cmp::min(remote_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
2278 for _ in 0..remote_hash_commitment_number_len {
2279 let payment_hash: PaymentHash = Readable::read(reader)?;
2280 let commitment_number = <U48 as Readable>::read(reader)?.0;
2281 if let Some(_) = remote_hash_commitment_number.insert(payment_hash, commitment_number) {
2282 return Err(DecodeError::InvalidValue);
2286 macro_rules! read_local_tx {
2289 let txid = Readable::read(reader)?;
2290 let revocation_key = Readable::read(reader)?;
2291 let a_htlc_key = Readable::read(reader)?;
2292 let b_htlc_key = Readable::read(reader)?;
2293 let delayed_payment_key = Readable::read(reader)?;
2294 let per_commitment_point = Readable::read(reader)?;
2295 let feerate_per_kw: u64 = Readable::read(reader)?;
2297 let htlcs_len: u64 = Readable::read(reader)?;
2298 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_len as usize, MAX_ALLOC_SIZE / 128));
2299 for _ in 0..htlcs_len {
2300 let htlc = read_htlc_in_commitment!();
2301 let sigs = match <u8 as Readable>::read(reader)? {
2303 1 => Some(Readable::read(reader)?),
2304 _ => return Err(DecodeError::InvalidValue),
2306 htlcs.push((htlc, sigs, Readable::read(reader)?));
2311 revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, per_commitment_point, feerate_per_kw,
2318 let prev_local_signed_commitment_tx = match <u8 as Readable>::read(reader)? {
2321 Some(read_local_tx!())
2323 _ => return Err(DecodeError::InvalidValue),
2325 let current_local_commitment_tx = read_local_tx!();
2327 let current_remote_commitment_number = <U48 as Readable>::read(reader)?.0;
2328 let current_local_commitment_number = <U48 as Readable>::read(reader)?.0;
2330 let payment_preimages_len: u64 = Readable::read(reader)?;
2331 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
2332 for _ in 0..payment_preimages_len {
2333 let preimage: PaymentPreimage = Readable::read(reader)?;
2334 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2335 if let Some(_) = payment_preimages.insert(hash, preimage) {
2336 return Err(DecodeError::InvalidValue);
2340 let pending_htlcs_updated_len: u64 = Readable::read(reader)?;
2341 let mut pending_htlcs_updated = Vec::with_capacity(cmp::min(pending_htlcs_updated_len as usize, MAX_ALLOC_SIZE / (32 + 8*3)));
2342 for _ in 0..pending_htlcs_updated_len {
2343 pending_htlcs_updated.push(Readable::read(reader)?);
2346 let pending_events_len: u64 = Readable::read(reader)?;
2347 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<events::Event>()));
2348 for _ in 0..pending_events_len {
2349 if let Some(event) = MaybeReadable::read(reader)? {
2350 pending_events.push(event);
2354 let last_block_hash: BlockHash = Readable::read(reader)?;
2356 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
2357 let mut onchain_events_waiting_threshold_conf = HashMap::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
2358 for _ in 0..waiting_threshold_conf_len {
2359 let height_target = Readable::read(reader)?;
2360 let events_len: u64 = Readable::read(reader)?;
2361 let mut events = Vec::with_capacity(cmp::min(events_len as usize, MAX_ALLOC_SIZE / 128));
2362 for _ in 0..events_len {
2363 let ev = match <u8 as Readable>::read(reader)? {
2365 let htlc_source = Readable::read(reader)?;
2366 let hash = Readable::read(reader)?;
2367 OnchainEvent::HTLCUpdate {
2368 htlc_update: (htlc_source, hash)
2372 let descriptor = Readable::read(reader)?;
2373 OnchainEvent::MaturingOutput {
2377 _ => return Err(DecodeError::InvalidValue),
2381 onchain_events_waiting_threshold_conf.insert(height_target, events);
2384 let outputs_to_watch_len: u64 = Readable::read(reader)?;
2385 let mut outputs_to_watch = HashMap::with_capacity(cmp::min(outputs_to_watch_len as usize, MAX_ALLOC_SIZE / (mem::size_of::<Txid>() + mem::size_of::<Vec<Script>>())));
2386 for _ in 0..outputs_to_watch_len {
2387 let txid = Readable::read(reader)?;
2388 let outputs_len: u64 = Readable::read(reader)?;
2389 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Script>()));
2390 for _ in 0..outputs_len {
2391 outputs.push(Readable::read(reader)?);
2393 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
2394 return Err(DecodeError::InvalidValue);
2397 let onchain_tx_handler = ReadableArgs::read(reader, logger.clone())?;
2399 let lockdown_from_offchain = Readable::read(reader)?;
2400 let local_tx_signed = Readable::read(reader)?;
2402 Ok((last_block_hash.clone(), ChannelMonitor {
2404 commitment_transaction_number_obscure_factor,
2407 broadcasted_local_revokable_script,
2408 remote_payment_script,
2413 current_remote_commitment_txid,
2414 prev_remote_commitment_txid,
2416 their_htlc_base_key,
2417 their_delayed_payment_base_key,
2418 funding_redeemscript,
2419 channel_value_satoshis,
2420 their_cur_revocation_points,
2423 their_to_self_delay,
2426 remote_claimable_outpoints,
2427 remote_commitment_txn_on_chain,
2428 remote_hash_commitment_number,
2430 prev_local_signed_commitment_tx,
2431 current_local_commitment_tx,
2432 current_remote_commitment_number,
2433 current_local_commitment_number,
2436 pending_htlcs_updated,
2439 onchain_events_waiting_threshold_conf,
2444 lockdown_from_offchain,
2448 secp_ctx: Secp256k1::new(),
2456 use bitcoin::blockdata::script::{Script, Builder};
2457 use bitcoin::blockdata::opcodes;
2458 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, SigHashType};
2459 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
2460 use bitcoin::util::bip143;
2461 use bitcoin::hashes::Hash;
2462 use bitcoin::hashes::sha256::Hash as Sha256;
2463 use bitcoin::hashes::hex::FromHex;
2464 use bitcoin::hash_types::Txid;
2466 use chain::transaction::OutPoint;
2467 use ln::channelmanager::{PaymentPreimage, PaymentHash};
2468 use ln::channelmonitor::ChannelMonitor;
2469 use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
2471 use ln::chan_utils::{HTLCOutputInCommitment, LocalCommitmentTransaction};
2472 use util::test_utils::TestLogger;
2473 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
2474 use bitcoin::secp256k1::Secp256k1;
2475 use rand::{thread_rng,Rng};
2477 use chain::keysinterface::InMemoryChannelKeys;
2480 fn test_prune_preimages() {
2481 let secp_ctx = Secp256k1::new();
2482 let logger = Arc::new(TestLogger::new());
2484 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
2485 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2487 let mut preimages = Vec::new();
2489 let mut rng = thread_rng();
2491 let mut preimage = PaymentPreimage([0; 32]);
2492 rng.fill_bytes(&mut preimage.0[..]);
2493 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2494 preimages.push((preimage, hash));
2498 macro_rules! preimages_slice_to_htlc_outputs {
2499 ($preimages_slice: expr) => {
2501 let mut res = Vec::new();
2502 for (idx, preimage) in $preimages_slice.iter().enumerate() {
2503 res.push((HTLCOutputInCommitment {
2507 payment_hash: preimage.1.clone(),
2508 transaction_output_index: Some(idx as u32),
2515 macro_rules! preimages_to_local_htlcs {
2516 ($preimages_slice: expr) => {
2518 let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2519 let res: Vec<_> = inp.drain(..).map(|e| { (e.0, None, e.1) }).collect();
2525 macro_rules! test_preimages_exist {
2526 ($preimages_slice: expr, $monitor: expr) => {
2527 for preimage in $preimages_slice {
2528 assert!($monitor.payment_preimages.contains_key(&preimage.1));
2533 let keys = InMemoryChannelKeys::new(
2535 SecretKey::from_slice(&[41; 32]).unwrap(),
2536 SecretKey::from_slice(&[41; 32]).unwrap(),
2537 SecretKey::from_slice(&[41; 32]).unwrap(),
2538 SecretKey::from_slice(&[41; 32]).unwrap(),
2539 SecretKey::from_slice(&[41; 32]).unwrap(),
2544 // Prune with one old state and a local commitment tx holding a few overlaps with the
2546 let mut monitor = ChannelMonitor::new(keys,
2547 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()), 0, &Script::new(),
2548 (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
2549 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
2550 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
2551 10, Script::new(), 46, 0, LocalCommitmentTransaction::dummy(), logger.clone());
2553 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..10])).unwrap();
2554 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key);
2555 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key);
2556 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key);
2557 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key);
2558 for &(ref preimage, ref hash) in preimages.iter() {
2559 monitor.provide_payment_preimage(hash, preimage);
2562 // Now provide a secret, pruning preimages 10-15
2563 let mut secret = [0; 32];
2564 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2565 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2566 assert_eq!(monitor.payment_preimages.len(), 15);
2567 test_preimages_exist!(&preimages[0..10], monitor);
2568 test_preimages_exist!(&preimages[15..20], monitor);
2570 // Now provide a further secret, pruning preimages 15-17
2571 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2572 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2573 assert_eq!(monitor.payment_preimages.len(), 13);
2574 test_preimages_exist!(&preimages[0..10], monitor);
2575 test_preimages_exist!(&preimages[17..20], monitor);
2577 // Now update local commitment tx info, pruning only element 18 as we still care about the
2578 // previous commitment tx's preimages too
2579 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..5])).unwrap();
2580 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2581 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2582 assert_eq!(monitor.payment_preimages.len(), 12);
2583 test_preimages_exist!(&preimages[0..10], monitor);
2584 test_preimages_exist!(&preimages[18..20], monitor);
2586 // But if we do it again, we'll prune 5-10
2587 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..3])).unwrap();
2588 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2589 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2590 assert_eq!(monitor.payment_preimages.len(), 5);
2591 test_preimages_exist!(&preimages[0..5], monitor);
2595 fn test_claim_txn_weight_computation() {
2596 // We test Claim txn weight, knowing that we want expected weigth and
2597 // not actual case to avoid sigs and time-lock delays hell variances.
2599 let secp_ctx = Secp256k1::new();
2600 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
2601 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
2602 let mut sum_actual_sigs = 0;
2604 macro_rules! sign_input {
2605 ($sighash_parts: expr, $input: expr, $idx: expr, $amount: expr, $input_type: expr, $sum_actual_sigs: expr) => {
2606 let htlc = HTLCOutputInCommitment {
2607 offered: if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::OfferedHTLC { true } else { false },
2609 cltv_expiry: 2 << 16,
2610 payment_hash: PaymentHash([1; 32]),
2611 transaction_output_index: Some($idx),
2613 let redeem_script = if *$input_type == InputDescriptors::RevokedOutput { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &pubkey, &pubkey, &pubkey) };
2614 let sighash = hash_to_message!(&$sighash_parts.sighash_all(&$input, &redeem_script, $amount)[..]);
2615 let sig = secp_ctx.sign(&sighash, &privkey);
2616 $input.witness.push(sig.serialize_der().to_vec());
2617 $input.witness[0].push(SigHashType::All as u8);
2618 sum_actual_sigs += $input.witness[0].len();
2619 if *$input_type == InputDescriptors::RevokedOutput {
2620 $input.witness.push(vec!(1));
2621 } else if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::RevokedReceivedHTLC {
2622 $input.witness.push(pubkey.clone().serialize().to_vec());
2623 } else if *$input_type == InputDescriptors::ReceivedHTLC {
2624 $input.witness.push(vec![0]);
2626 $input.witness.push(PaymentPreimage([1; 32]).0.to_vec());
2628 $input.witness.push(redeem_script.into_bytes());
2629 println!("witness[0] {}", $input.witness[0].len());
2630 println!("witness[1] {}", $input.witness[1].len());
2631 println!("witness[2] {}", $input.witness[2].len());
2635 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
2636 let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
2638 // Justice tx with 1 to_local, 2 revoked offered HTLCs, 1 revoked received HTLCs
2639 let mut claim_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2641 claim_tx.input.push(TxIn {
2642 previous_output: BitcoinOutPoint {
2646 script_sig: Script::new(),
2647 sequence: 0xfffffffd,
2648 witness: Vec::new(),
2651 claim_tx.output.push(TxOut {
2652 script_pubkey: script_pubkey.clone(),
2655 let base_weight = claim_tx.get_weight();
2656 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2657 let inputs_des = vec![InputDescriptors::RevokedOutput, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedReceivedHTLC];
2658 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2659 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2661 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));
2663 // Claim tx with 1 offered HTLCs, 3 received HTLCs
2664 claim_tx.input.clear();
2665 sum_actual_sigs = 0;
2667 claim_tx.input.push(TxIn {
2668 previous_output: BitcoinOutPoint {
2672 script_sig: Script::new(),
2673 sequence: 0xfffffffd,
2674 witness: Vec::new(),
2677 let base_weight = claim_tx.get_weight();
2678 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2679 let inputs_des = vec![InputDescriptors::OfferedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC];
2680 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2681 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2683 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));
2685 // Justice tx with 1 revoked HTLC-Success tx output
2686 claim_tx.input.clear();
2687 sum_actual_sigs = 0;
2688 claim_tx.input.push(TxIn {
2689 previous_output: BitcoinOutPoint {
2693 script_sig: Script::new(),
2694 sequence: 0xfffffffd,
2695 witness: Vec::new(),
2697 let base_weight = claim_tx.get_weight();
2698 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2699 let inputs_des = vec![InputDescriptors::RevokedOutput];
2700 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2701 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2703 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));
2706 // Further testing is done in the ChannelManager integration tests.