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 latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date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 /// Indicates our channel is likely a stale version, we're closing, but this update should
593 /// allow us to spend what is ours if our counterparty broadcasts their latest state.
594 RescueRemoteCommitmentTXInfo {
595 their_current_per_commitment_point: PublicKey,
597 /// Used to indicate that the no future updates will occur, and likely that the latest local
598 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
600 /// If set to false, we shouldn't broadcast the latest local commitment transaction as we
601 /// think we've fallen behind!
602 should_broadcast: bool,
606 impl Writeable for ChannelMonitorUpdateStep {
607 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
609 &ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { ref commitment_tx, ref htlc_outputs } => {
611 commitment_tx.write(w)?;
612 (htlc_outputs.len() as u64).write(w)?;
613 for &(ref output, ref signature, ref source) in htlc_outputs.iter() {
619 &ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { ref unsigned_commitment_tx, ref htlc_outputs, ref commitment_number, ref their_revocation_point } => {
621 unsigned_commitment_tx.write(w)?;
622 commitment_number.write(w)?;
623 their_revocation_point.write(w)?;
624 (htlc_outputs.len() as u64).write(w)?;
625 for &(ref output, ref source) in htlc_outputs.iter() {
627 source.as_ref().map(|b| b.as_ref()).write(w)?;
630 &ChannelMonitorUpdateStep::PaymentPreimage { ref payment_preimage } => {
632 payment_preimage.write(w)?;
634 &ChannelMonitorUpdateStep::CommitmentSecret { ref idx, ref secret } => {
639 &ChannelMonitorUpdateStep::RescueRemoteCommitmentTXInfo { ref their_current_per_commitment_point } => {
641 their_current_per_commitment_point.write(w)?;
643 &ChannelMonitorUpdateStep::ChannelForceClosed { ref should_broadcast } => {
645 should_broadcast.write(w)?;
651 impl Readable for ChannelMonitorUpdateStep {
652 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
653 match Readable::read(r)? {
655 Ok(ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo {
656 commitment_tx: Readable::read(r)?,
658 let len: u64 = Readable::read(r)?;
659 let mut res = Vec::new();
661 res.push((Readable::read(r)?, Readable::read(r)?, Readable::read(r)?));
668 Ok(ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo {
669 unsigned_commitment_tx: Readable::read(r)?,
670 commitment_number: Readable::read(r)?,
671 their_revocation_point: Readable::read(r)?,
673 let len: u64 = Readable::read(r)?;
674 let mut res = Vec::new();
676 res.push((Readable::read(r)?, <Option<HTLCSource> as Readable>::read(r)?.map(|o| Box::new(o))));
683 Ok(ChannelMonitorUpdateStep::PaymentPreimage {
684 payment_preimage: Readable::read(r)?,
688 Ok(ChannelMonitorUpdateStep::CommitmentSecret {
689 idx: Readable::read(r)?,
690 secret: Readable::read(r)?,
694 Ok(ChannelMonitorUpdateStep::RescueRemoteCommitmentTXInfo {
695 their_current_per_commitment_point: Readable::read(r)?,
699 Ok(ChannelMonitorUpdateStep::ChannelForceClosed {
700 should_broadcast: Readable::read(r)?
703 _ => Err(DecodeError::InvalidValue),
708 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
709 /// on-chain transactions to ensure no loss of funds occurs.
711 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
712 /// information and are actively monitoring the chain.
714 /// Pending Events or updated HTLCs which have not yet been read out by
715 /// get_and_clear_pending_htlcs_updated or get_and_clear_pending_events are serialized to disk and
716 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
717 /// gotten are fully handled before re-serializing the new state.
718 pub struct ChannelMonitor<ChanSigner: ChannelKeys> {
719 latest_update_id: u64,
720 commitment_transaction_number_obscure_factor: u64,
722 destination_script: Script,
723 broadcasted_local_revokable_script: Option<(Script, SecretKey, Script)>,
724 broadcasted_remote_payment_script: Option<(Script, SecretKey)>,
725 shutdown_script: Script,
728 funding_info: (OutPoint, Script),
729 current_remote_commitment_txid: Option<Txid>,
730 prev_remote_commitment_txid: Option<Txid>,
732 their_htlc_base_key: PublicKey,
733 their_delayed_payment_base_key: PublicKey,
734 funding_redeemscript: Script,
735 channel_value_satoshis: u64,
736 // first is the idx of the first of the two revocation points
737 their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
739 our_to_self_delay: u16,
740 their_to_self_delay: u16,
742 commitment_secrets: CounterpartyCommitmentSecrets,
743 remote_claimable_outpoints: HashMap<Txid, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
744 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
745 /// Nor can we figure out their commitment numbers without the commitment transaction they are
746 /// spending. Thus, in order to claim them via revocation key, we track all the remote
747 /// commitment transactions which we find on-chain, mapping them to the commitment number which
748 /// can be used to derive the revocation key and claim the transactions.
749 remote_commitment_txn_on_chain: HashMap<Txid, (u64, Vec<Script>)>,
750 /// Cache used to make pruning of payment_preimages faster.
751 /// Maps payment_hash values to commitment numbers for remote transactions for non-revoked
752 /// remote transactions (ie should remain pretty small).
753 /// Serialized to disk but should generally not be sent to Watchtowers.
754 remote_hash_commitment_number: HashMap<PaymentHash, u64>,
756 // We store two local commitment transactions to avoid any race conditions where we may update
757 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
758 // various monitors for one channel being out of sync, and us broadcasting a local
759 // transaction for which we have deleted claim information on some watchtowers.
760 prev_local_signed_commitment_tx: Option<LocalSignedTx>,
761 current_local_commitment_tx: LocalSignedTx,
763 // Used just for ChannelManager to make sure it has the latest channel data during
765 current_remote_commitment_number: u64,
766 // Used just for ChannelManager to make sure it has the latest channel data during
768 current_local_commitment_number: u64,
770 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
772 pending_htlcs_updated: Vec<HTLCUpdate>,
773 pending_events: Vec<events::Event>,
775 // Used to track onchain events, i.e transactions parts of channels confirmed on chain, on which
776 // we have to take actions once they reach enough confs. Key is a block height timer, i.e we enforce
777 // actions when we receive a block with given height. Actions depend on OnchainEvent type.
778 onchain_events_waiting_threshold_conf: HashMap<u32, Vec<OnchainEvent>>,
780 // If we get serialized out and re-read, we need to make sure that the chain monitoring
781 // interface knows about the TXOs that we want to be notified of spends of. We could probably
782 // be smart and derive them from the above storage fields, but its much simpler and more
783 // Obviously Correct (tm) if we just keep track of them explicitly.
784 outputs_to_watch: HashMap<Txid, Vec<Script>>,
787 pub onchain_tx_handler: OnchainTxHandler<ChanSigner>,
789 onchain_tx_handler: OnchainTxHandler<ChanSigner>,
791 // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
792 // channel has been force-closed. After this is set, no further local commitment transaction
793 // updates may occur, and we panic!() if one is provided.
794 lockdown_from_offchain: bool,
796 // Set once we've signed a local commitment transaction and handed it over to our
797 // OnchainTxHandler. After this is set, no future updates to our local commitment transactions
798 // may occur, and we fail any such monitor updates.
799 local_tx_signed: bool,
801 // We simply modify last_block_hash in Channel's block_connected so that serialization is
802 // consistent but hopefully the users' copy handles block_connected in a consistent way.
803 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
804 // their last_block_hash from its state and not based on updated copies that didn't run through
805 // the full block_connected).
806 pub(crate) last_block_hash: BlockHash,
807 secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
811 #[cfg(any(test, feature = "fuzztarget"))]
812 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
813 /// underlying object
814 impl<ChanSigner: ChannelKeys> PartialEq for ChannelMonitor<ChanSigner> {
815 fn eq(&self, other: &Self) -> bool {
816 if self.latest_update_id != other.latest_update_id ||
817 self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
818 self.destination_script != other.destination_script ||
819 self.broadcasted_local_revokable_script != other.broadcasted_local_revokable_script ||
820 self.broadcasted_remote_payment_script != other.broadcasted_remote_payment_script ||
821 self.keys.pubkeys() != other.keys.pubkeys() ||
822 self.funding_info != other.funding_info ||
823 self.current_remote_commitment_txid != other.current_remote_commitment_txid ||
824 self.prev_remote_commitment_txid != other.prev_remote_commitment_txid ||
825 self.their_htlc_base_key != other.their_htlc_base_key ||
826 self.their_delayed_payment_base_key != other.their_delayed_payment_base_key ||
827 self.funding_redeemscript != other.funding_redeemscript ||
828 self.channel_value_satoshis != other.channel_value_satoshis ||
829 self.their_cur_revocation_points != other.their_cur_revocation_points ||
830 self.our_to_self_delay != other.our_to_self_delay ||
831 self.their_to_self_delay != other.their_to_self_delay ||
832 self.commitment_secrets != other.commitment_secrets ||
833 self.remote_claimable_outpoints != other.remote_claimable_outpoints ||
834 self.remote_commitment_txn_on_chain != other.remote_commitment_txn_on_chain ||
835 self.remote_hash_commitment_number != other.remote_hash_commitment_number ||
836 self.prev_local_signed_commitment_tx != other.prev_local_signed_commitment_tx ||
837 self.current_remote_commitment_number != other.current_remote_commitment_number ||
838 self.current_local_commitment_number != other.current_local_commitment_number ||
839 self.current_local_commitment_tx != other.current_local_commitment_tx ||
840 self.payment_preimages != other.payment_preimages ||
841 self.pending_htlcs_updated != other.pending_htlcs_updated ||
842 self.pending_events.len() != other.pending_events.len() || // We trust events to round-trip properly
843 self.onchain_events_waiting_threshold_conf != other.onchain_events_waiting_threshold_conf ||
844 self.outputs_to_watch != other.outputs_to_watch ||
845 self.lockdown_from_offchain != other.lockdown_from_offchain ||
846 self.local_tx_signed != other.local_tx_signed
855 impl<ChanSigner: ChannelKeys + Writeable> ChannelMonitor<ChanSigner> {
856 /// Writes this monitor into the given writer, suitable for writing to disk.
858 /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
859 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
860 /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
861 /// returned block hash and the the current chain and then reconnecting blocks to get to the
862 /// best chain) upon deserializing the object!
863 pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
864 //TODO: We still write out all the serialization here manually instead of using the fancy
865 //serialization framework we have, we should migrate things over to it.
866 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
867 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
869 self.latest_update_id.write(writer)?;
871 // Set in initial Channel-object creation, so should always be set by now:
872 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
874 self.destination_script.write(writer)?;
875 if let Some(ref broadcasted_local_revokable_script) = self.broadcasted_local_revokable_script {
876 writer.write_all(&[0; 1])?;
877 broadcasted_local_revokable_script.0.write(writer)?;
878 broadcasted_local_revokable_script.1.write(writer)?;
879 broadcasted_local_revokable_script.2.write(writer)?;
881 writer.write_all(&[1; 1])?;
884 if let Some(ref broadcasted_remote_payment_script) = self.broadcasted_remote_payment_script {
885 writer.write_all(&[0; 1])?;
886 broadcasted_remote_payment_script.0.write(writer)?;
887 broadcasted_remote_payment_script.1.write(writer)?;
889 writer.write_all(&[1; 1])?;
891 self.shutdown_script.write(writer)?;
893 self.keys.write(writer)?;
894 writer.write_all(&self.funding_info.0.txid[..])?;
895 writer.write_all(&byte_utils::be16_to_array(self.funding_info.0.index))?;
896 self.funding_info.1.write(writer)?;
897 self.current_remote_commitment_txid.write(writer)?;
898 self.prev_remote_commitment_txid.write(writer)?;
900 writer.write_all(&self.their_htlc_base_key.serialize())?;
901 writer.write_all(&self.their_delayed_payment_base_key.serialize())?;
902 self.funding_redeemscript.write(writer)?;
903 self.channel_value_satoshis.write(writer)?;
905 match self.their_cur_revocation_points {
906 Some((idx, pubkey, second_option)) => {
907 writer.write_all(&byte_utils::be48_to_array(idx))?;
908 writer.write_all(&pubkey.serialize())?;
909 match second_option {
910 Some(second_pubkey) => {
911 writer.write_all(&second_pubkey.serialize())?;
914 writer.write_all(&[0; 33])?;
919 writer.write_all(&byte_utils::be48_to_array(0))?;
923 writer.write_all(&byte_utils::be16_to_array(self.our_to_self_delay))?;
924 writer.write_all(&byte_utils::be16_to_array(self.their_to_self_delay))?;
926 self.commitment_secrets.write(writer)?;
928 macro_rules! serialize_htlc_in_commitment {
929 ($htlc_output: expr) => {
930 writer.write_all(&[$htlc_output.offered as u8; 1])?;
931 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
932 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
933 writer.write_all(&$htlc_output.payment_hash.0[..])?;
934 $htlc_output.transaction_output_index.write(writer)?;
938 writer.write_all(&byte_utils::be64_to_array(self.remote_claimable_outpoints.len() as u64))?;
939 for (ref txid, ref htlc_infos) in self.remote_claimable_outpoints.iter() {
940 writer.write_all(&txid[..])?;
941 writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
942 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
943 serialize_htlc_in_commitment!(htlc_output);
944 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
948 writer.write_all(&byte_utils::be64_to_array(self.remote_commitment_txn_on_chain.len() as u64))?;
949 for (ref txid, &(commitment_number, ref txouts)) in self.remote_commitment_txn_on_chain.iter() {
950 writer.write_all(&txid[..])?;
951 writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
952 (txouts.len() as u64).write(writer)?;
953 for script in txouts.iter() {
954 script.write(writer)?;
958 writer.write_all(&byte_utils::be64_to_array(self.remote_hash_commitment_number.len() as u64))?;
959 for (ref payment_hash, commitment_number) in self.remote_hash_commitment_number.iter() {
960 writer.write_all(&payment_hash.0[..])?;
961 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
964 macro_rules! serialize_local_tx {
965 ($local_tx: expr) => {
966 $local_tx.txid.write(writer)?;
967 writer.write_all(&$local_tx.revocation_key.serialize())?;
968 writer.write_all(&$local_tx.a_htlc_key.serialize())?;
969 writer.write_all(&$local_tx.b_htlc_key.serialize())?;
970 writer.write_all(&$local_tx.delayed_payment_key.serialize())?;
971 writer.write_all(&$local_tx.per_commitment_point.serialize())?;
973 writer.write_all(&byte_utils::be64_to_array($local_tx.feerate_per_kw))?;
974 writer.write_all(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64))?;
975 for &(ref htlc_output, ref sig, ref htlc_source) in $local_tx.htlc_outputs.iter() {
976 serialize_htlc_in_commitment!(htlc_output);
977 if let &Some(ref their_sig) = sig {
979 writer.write_all(&their_sig.serialize_compact())?;
983 htlc_source.write(writer)?;
988 if let Some(ref prev_local_tx) = self.prev_local_signed_commitment_tx {
989 writer.write_all(&[1; 1])?;
990 serialize_local_tx!(prev_local_tx);
992 writer.write_all(&[0; 1])?;
995 serialize_local_tx!(self.current_local_commitment_tx);
997 writer.write_all(&byte_utils::be48_to_array(self.current_remote_commitment_number))?;
998 writer.write_all(&byte_utils::be48_to_array(self.current_local_commitment_number))?;
1000 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
1001 for payment_preimage in self.payment_preimages.values() {
1002 writer.write_all(&payment_preimage.0[..])?;
1005 writer.write_all(&byte_utils::be64_to_array(self.pending_htlcs_updated.len() as u64))?;
1006 for data in self.pending_htlcs_updated.iter() {
1007 data.write(writer)?;
1010 writer.write_all(&byte_utils::be64_to_array(self.pending_events.len() as u64))?;
1011 for event in self.pending_events.iter() {
1012 event.write(writer)?;
1015 self.last_block_hash.write(writer)?;
1017 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_waiting_threshold_conf.len() as u64))?;
1018 for (ref target, ref events) in self.onchain_events_waiting_threshold_conf.iter() {
1019 writer.write_all(&byte_utils::be32_to_array(**target))?;
1020 writer.write_all(&byte_utils::be64_to_array(events.len() as u64))?;
1021 for ev in events.iter() {
1023 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1025 htlc_update.0.write(writer)?;
1026 htlc_update.1.write(writer)?;
1028 OnchainEvent::MaturingOutput { ref descriptor } => {
1030 descriptor.write(writer)?;
1036 (self.outputs_to_watch.len() as u64).write(writer)?;
1037 for (txid, output_scripts) in self.outputs_to_watch.iter() {
1038 txid.write(writer)?;
1039 (output_scripts.len() as u64).write(writer)?;
1040 for script in output_scripts.iter() {
1041 script.write(writer)?;
1044 self.onchain_tx_handler.write(writer)?;
1046 self.lockdown_from_offchain.write(writer)?;
1047 self.local_tx_signed.write(writer)?;
1053 impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
1054 pub(super) fn new(keys: ChanSigner, shutdown_pubkey: &PublicKey,
1055 our_to_self_delay: u16, destination_script: &Script, funding_info: (OutPoint, Script),
1056 their_htlc_base_key: &PublicKey, their_delayed_payment_base_key: &PublicKey,
1057 their_to_self_delay: u16, funding_redeemscript: Script, channel_value_satoshis: u64,
1058 commitment_transaction_number_obscure_factor: u64,
1059 initial_local_commitment_tx: LocalCommitmentTransaction,
1060 logger: Arc<Logger>) -> ChannelMonitor<ChanSigner> {
1062 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
1063 let our_channel_close_key_hash = WPubkeyHash::hash(&shutdown_pubkey.serialize());
1064 let shutdown_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
1066 let mut onchain_tx_handler = OnchainTxHandler::new(destination_script.clone(), keys.clone(), their_to_self_delay, logger.clone());
1068 let local_tx_sequence = initial_local_commitment_tx.unsigned_tx.input[0].sequence as u64;
1069 let local_tx_locktime = initial_local_commitment_tx.unsigned_tx.lock_time as u64;
1070 let local_commitment_tx = LocalSignedTx {
1071 txid: initial_local_commitment_tx.txid(),
1072 revocation_key: initial_local_commitment_tx.local_keys.revocation_key,
1073 a_htlc_key: initial_local_commitment_tx.local_keys.a_htlc_key,
1074 b_htlc_key: initial_local_commitment_tx.local_keys.b_htlc_key,
1075 delayed_payment_key: initial_local_commitment_tx.local_keys.a_delayed_payment_key,
1076 per_commitment_point: initial_local_commitment_tx.local_keys.per_commitment_point,
1077 feerate_per_kw: initial_local_commitment_tx.feerate_per_kw,
1078 htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
1080 // Returning a monitor error before updating tracking points means in case of using
1081 // a concurrent watchtower implementation for same channel, if this one doesn't
1082 // reject update as we do, you MAY have the latest local valid commitment tx onchain
1083 // for which you want to spend outputs. We're NOT robust again this scenario right
1084 // now but we should consider it later.
1085 onchain_tx_handler.provide_latest_local_tx(initial_local_commitment_tx).unwrap();
1088 latest_update_id: 0,
1089 commitment_transaction_number_obscure_factor,
1091 destination_script: destination_script.clone(),
1092 broadcasted_local_revokable_script: None,
1093 broadcasted_remote_payment_script: None,
1098 current_remote_commitment_txid: None,
1099 prev_remote_commitment_txid: None,
1101 their_htlc_base_key: their_htlc_base_key.clone(),
1102 their_delayed_payment_base_key: their_delayed_payment_base_key.clone(),
1103 funding_redeemscript,
1104 channel_value_satoshis: channel_value_satoshis,
1105 their_cur_revocation_points: None,
1108 their_to_self_delay,
1110 commitment_secrets: CounterpartyCommitmentSecrets::new(),
1111 remote_claimable_outpoints: HashMap::new(),
1112 remote_commitment_txn_on_chain: HashMap::new(),
1113 remote_hash_commitment_number: HashMap::new(),
1115 prev_local_signed_commitment_tx: None,
1116 current_local_commitment_tx: local_commitment_tx,
1117 current_remote_commitment_number: 1 << 48,
1118 current_local_commitment_number: 0xffff_ffff_ffff - ((((local_tx_sequence & 0xffffff) << 3*8) | (local_tx_locktime as u64 & 0xffffff)) ^ commitment_transaction_number_obscure_factor),
1120 payment_preimages: HashMap::new(),
1121 pending_htlcs_updated: Vec::new(),
1122 pending_events: Vec::new(),
1124 onchain_events_waiting_threshold_conf: HashMap::new(),
1125 outputs_to_watch: HashMap::new(),
1129 lockdown_from_offchain: false,
1130 local_tx_signed: false,
1132 last_block_hash: Default::default(),
1133 secp_ctx: Secp256k1::new(),
1138 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
1139 /// needed by local commitment transactions HTCLs nor by remote ones. Unless we haven't already seen remote
1140 /// commitment transaction's secret, they are de facto pruned (we can use revocation key).
1141 pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
1142 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
1143 return Err(MonitorUpdateError("Previous secret did not match new one"));
1146 // Prune HTLCs from the previous remote commitment tx so we don't generate failure/fulfill
1147 // events for now-revoked/fulfilled HTLCs.
1148 if let Some(txid) = self.prev_remote_commitment_txid.take() {
1149 for &mut (_, ref mut source) in self.remote_claimable_outpoints.get_mut(&txid).unwrap() {
1154 if !self.payment_preimages.is_empty() {
1155 let cur_local_signed_commitment_tx = &self.current_local_commitment_tx;
1156 let prev_local_signed_commitment_tx = self.prev_local_signed_commitment_tx.as_ref();
1157 let min_idx = self.get_min_seen_secret();
1158 let remote_hash_commitment_number = &mut self.remote_hash_commitment_number;
1160 self.payment_preimages.retain(|&k, _| {
1161 for &(ref htlc, _, _) in cur_local_signed_commitment_tx.htlc_outputs.iter() {
1162 if k == htlc.payment_hash {
1166 if let Some(prev_local_commitment_tx) = prev_local_signed_commitment_tx {
1167 for &(ref htlc, _, _) in prev_local_commitment_tx.htlc_outputs.iter() {
1168 if k == htlc.payment_hash {
1173 let contains = if let Some(cn) = remote_hash_commitment_number.get(&k) {
1180 remote_hash_commitment_number.remove(&k);
1189 /// Informs this monitor of the latest remote (ie non-broadcastable) commitment transaction.
1190 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
1191 /// possibly future revocation/preimage information) to claim outputs where possible.
1192 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
1193 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) {
1194 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
1195 // so that a remote monitor doesn't learn anything unless there is a malicious close.
1196 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
1198 for &(ref htlc, _) in &htlc_outputs {
1199 self.remote_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
1202 let new_txid = unsigned_commitment_tx.txid();
1203 log_trace!(self, "Tracking new remote commitment transaction with txid {} at commitment number {} with {} HTLC outputs", new_txid, commitment_number, htlc_outputs.len());
1204 log_trace!(self, "New potential remote commitment transaction: {}", encode::serialize_hex(unsigned_commitment_tx));
1205 self.prev_remote_commitment_txid = self.current_remote_commitment_txid.take();
1206 self.current_remote_commitment_txid = Some(new_txid);
1207 self.remote_claimable_outpoints.insert(new_txid, htlc_outputs);
1208 self.current_remote_commitment_number = commitment_number;
1209 //TODO: Merge this into the other per-remote-transaction output storage stuff
1210 match self.their_cur_revocation_points {
1211 Some(old_points) => {
1212 if old_points.0 == commitment_number + 1 {
1213 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
1214 } else if old_points.0 == commitment_number + 2 {
1215 if let Some(old_second_point) = old_points.2 {
1216 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
1218 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1221 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1225 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1230 pub(super) fn provide_rescue_remote_commitment_tx_info(&mut self, their_revocation_point: PublicKey) {
1231 if let Ok(payment_key) = chan_utils::derive_public_key(&self.secp_ctx, &their_revocation_point, &self.keys.pubkeys().payment_basepoint) {
1232 let to_remote_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0)
1233 .push_slice(&WPubkeyHash::hash(&payment_key.serialize())[..])
1235 if let Ok(to_remote_key) = chan_utils::derive_private_key(&self.secp_ctx, &their_revocation_point, &self.keys.payment_base_key()) {
1236 self.broadcasted_remote_payment_script = Some((to_remote_script, to_remote_key));
1241 /// Informs this monitor of the latest local (ie broadcastable) commitment transaction. The
1242 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
1243 /// is important that any clones of this channel monitor (including remote clones) by kept
1244 /// up-to-date as our local commitment transaction is updated.
1245 /// Panics if set_their_to_self_delay has never been called.
1246 pub(super) fn provide_latest_local_commitment_tx_info(&mut self, commitment_tx: LocalCommitmentTransaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), MonitorUpdateError> {
1247 if self.local_tx_signed {
1248 return Err(MonitorUpdateError("A local commitment tx has already been signed, no new local commitment txn can be sent to our counterparty"));
1250 let txid = commitment_tx.txid();
1251 let sequence = commitment_tx.unsigned_tx.input[0].sequence as u64;
1252 let locktime = commitment_tx.unsigned_tx.lock_time as u64;
1253 let mut new_local_commitment_tx = LocalSignedTx {
1255 revocation_key: commitment_tx.local_keys.revocation_key,
1256 a_htlc_key: commitment_tx.local_keys.a_htlc_key,
1257 b_htlc_key: commitment_tx.local_keys.b_htlc_key,
1258 delayed_payment_key: commitment_tx.local_keys.a_delayed_payment_key,
1259 per_commitment_point: commitment_tx.local_keys.per_commitment_point,
1260 feerate_per_kw: commitment_tx.feerate_per_kw,
1261 htlc_outputs: htlc_outputs,
1263 // Returning a monitor error before updating tracking points means in case of using
1264 // a concurrent watchtower implementation for same channel, if this one doesn't
1265 // reject update as we do, you MAY have the latest local valid commitment tx onchain
1266 // for which you want to spend outputs. We're NOT robust again this scenario right
1267 // now but we should consider it later.
1268 if let Err(_) = self.onchain_tx_handler.provide_latest_local_tx(commitment_tx) {
1269 return Err(MonitorUpdateError("Local commitment signed has already been signed, no further update of LOCAL commitment transaction is allowed"));
1271 self.current_local_commitment_number = 0xffff_ffff_ffff - ((((sequence & 0xffffff) << 3*8) | (locktime as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
1272 mem::swap(&mut new_local_commitment_tx, &mut self.current_local_commitment_tx);
1273 self.prev_local_signed_commitment_tx = Some(new_local_commitment_tx);
1277 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
1278 /// commitment_tx_infos which contain the payment hash have been revoked.
1279 pub(super) fn provide_payment_preimage(&mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage) {
1280 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
1283 pub(super) fn broadcast_latest_local_commitment_txn<B: Deref>(&mut self, broadcaster: &B)
1284 where B::Target: BroadcasterInterface,
1286 for tx in self.get_latest_local_commitment_txn().iter() {
1287 broadcaster.broadcast_transaction(tx);
1291 /// Used in Channel to cheat wrt the update_ids since it plays games, will be removed soon!
1292 pub(super) fn update_monitor_ooo(&mut self, mut updates: ChannelMonitorUpdate) -> Result<(), MonitorUpdateError> {
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::RescueRemoteCommitmentTXInfo { their_current_per_commitment_point } =>
1306 self.provide_rescue_remote_commitment_tx_info(their_current_per_commitment_point),
1307 ChannelMonitorUpdateStep::ChannelForceClosed { .. } => {},
1310 self.latest_update_id = updates.update_id;
1314 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
1317 /// panics if the given update is not the next update by update_id.
1318 pub fn update_monitor<B: Deref>(&mut self, mut updates: ChannelMonitorUpdate, broadcaster: &B) -> Result<(), MonitorUpdateError>
1319 where B::Target: BroadcasterInterface,
1321 if self.latest_update_id + 1 != updates.update_id {
1322 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
1324 for update in updates.updates.drain(..) {
1326 ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { commitment_tx, htlc_outputs } => {
1327 if self.lockdown_from_offchain { panic!(); }
1328 self.provide_latest_local_commitment_tx_info(commitment_tx, htlc_outputs)?
1330 ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
1331 self.provide_latest_remote_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point),
1332 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
1333 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
1334 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
1335 self.provide_secret(idx, secret)?,
1336 ChannelMonitorUpdateStep::RescueRemoteCommitmentTXInfo { their_current_per_commitment_point } =>
1337 self.provide_rescue_remote_commitment_tx_info(their_current_per_commitment_point),
1338 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
1339 self.lockdown_from_offchain = true;
1340 if should_broadcast {
1341 self.broadcast_latest_local_commitment_txn(broadcaster);
1343 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");
1348 self.latest_update_id = updates.update_id;
1352 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
1354 pub fn get_latest_update_id(&self) -> u64 {
1355 self.latest_update_id
1358 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
1359 pub fn get_funding_txo(&self) -> OutPoint {
1363 /// Gets a list of txids, with their output scripts (in the order they appear in the
1364 /// transaction), which we must learn about spends of via block_connected().
1365 pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<Script>> {
1366 &self.outputs_to_watch
1369 /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
1370 /// Generally useful when deserializing as during normal operation the return values of
1371 /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
1372 /// that the get_funding_txo outpoint and transaction must also be monitored for!).
1373 pub fn get_monitored_outpoints(&self) -> Vec<(Txid, u32, &Script)> {
1374 let mut res = Vec::with_capacity(self.remote_commitment_txn_on_chain.len() * 2);
1375 for (ref txid, &(_, ref outputs)) in self.remote_commitment_txn_on_chain.iter() {
1376 for (idx, output) in outputs.iter().enumerate() {
1377 res.push(((*txid).clone(), idx as u32, output));
1383 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1384 /// ChannelManager via ManyChannelMonitor::get_and_clear_pending_htlcs_updated().
1385 pub fn get_and_clear_pending_htlcs_updated(&mut self) -> Vec<HTLCUpdate> {
1386 let mut ret = Vec::new();
1387 mem::swap(&mut ret, &mut self.pending_htlcs_updated);
1391 /// Gets the list of pending events which were generated by previous actions, clearing the list
1394 /// This is called by ManyChannelMonitor::get_and_clear_pending_events() and is equivalent to
1395 /// EventsProvider::get_and_clear_pending_events() except that it requires &mut self as we do
1396 /// no internal locking in ChannelMonitors.
1397 pub fn get_and_clear_pending_events(&mut self) -> Vec<events::Event> {
1398 let mut ret = Vec::new();
1399 mem::swap(&mut ret, &mut self.pending_events);
1403 /// Can only fail if idx is < get_min_seen_secret
1404 pub(super) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
1405 self.commitment_secrets.get_secret(idx)
1408 pub(super) fn get_min_seen_secret(&self) -> u64 {
1409 self.commitment_secrets.get_min_seen_secret()
1412 pub(super) fn get_cur_remote_commitment_number(&self) -> u64 {
1413 self.current_remote_commitment_number
1416 pub(super) fn get_cur_local_commitment_number(&self) -> u64 {
1417 self.current_local_commitment_number
1420 /// Attempts to claim a remote commitment transaction's outputs using the revocation key and
1421 /// data in remote_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
1422 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
1423 /// HTLC-Success/HTLC-Timeout transactions.
1424 /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
1425 /// revoked remote commitment tx
1426 fn check_spend_remote_transaction(&mut self, tx: &Transaction, height: u32) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) {
1427 // Most secp and related errors trying to create keys means we have no hope of constructing
1428 // a spend transaction...so we return no transactions to broadcast
1429 let mut claimable_outpoints = Vec::new();
1430 let mut watch_outputs = Vec::new();
1432 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1433 let per_commitment_option = self.remote_claimable_outpoints.get(&commitment_txid);
1435 macro_rules! ignore_error {
1436 ( $thing : expr ) => {
1439 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs))
1444 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);
1445 if commitment_number >= self.get_min_seen_secret() {
1446 let secret = self.get_secret(commitment_number).unwrap();
1447 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1448 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1449 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.keys.pubkeys().revocation_basepoint));
1450 let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &self.keys.revocation_base_key()));
1451 let b_htlc_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &self.keys.pubkeys().htlc_basepoint));
1452 let local_payment_key = ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, &per_commitment_point, &self.keys.payment_base_key()));
1453 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));
1454 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));
1456 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.our_to_self_delay, &delayed_key);
1457 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1459 self.broadcasted_remote_payment_script = {
1460 // Note that the Network here is ignored as we immediately drop the address for the
1461 // script_pubkey version
1462 let payment_hash160 = WPubkeyHash::hash(&PublicKey::from_secret_key(&self.secp_ctx, &local_payment_key).serialize());
1463 Some((Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_hash160[..]).into_script(), local_payment_key))
1466 // First, process non-htlc outputs (to_local & to_remote)
1467 for (idx, outp) in tx.output.iter().enumerate() {
1468 if outp.script_pubkey == revokeable_p2wsh {
1469 let witness_data = InputMaterial::Revoked { witness_script: revokeable_redeemscript.clone(), pubkey: Some(revocation_pubkey), key: revocation_key, is_htlc: false, amount: outp.value };
1470 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});
1474 // Then, try to find revoked htlc outputs
1475 if let Some(ref per_commitment_data) = per_commitment_option {
1476 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1477 if let Some(transaction_output_index) = htlc.transaction_output_index {
1478 let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1479 if transaction_output_index as usize >= tx.output.len() ||
1480 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
1481 tx.output[transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
1482 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1484 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 };
1485 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable: true, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1490 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
1491 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
1492 // We're definitely a remote commitment transaction!
1493 log_trace!(self, "Got broadcast of revoked remote commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
1494 watch_outputs.append(&mut tx.output.clone());
1495 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1497 macro_rules! check_htlc_fails {
1498 ($txid: expr, $commitment_tx: expr) => {
1499 if let Some(ref outpoints) = self.remote_claimable_outpoints.get($txid) {
1500 for &(ref htlc, ref source_option) in outpoints.iter() {
1501 if let &Some(ref source) = source_option {
1502 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), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1503 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1504 hash_map::Entry::Occupied(mut entry) => {
1505 let e = entry.get_mut();
1506 e.retain(|ref event| {
1508 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1509 return htlc_update.0 != **source
1514 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1516 hash_map::Entry::Vacant(entry) => {
1517 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1525 if let Some(ref txid) = self.current_remote_commitment_txid {
1526 check_htlc_fails!(txid, "current");
1528 if let Some(ref txid) = self.prev_remote_commitment_txid {
1529 check_htlc_fails!(txid, "remote");
1531 // No need to check local commitment txn, symmetric HTLCSource must be present as per-htlc data on remote commitment tx
1533 } else if let Some(per_commitment_data) = per_commitment_option {
1534 // While this isn't useful yet, there is a potential race where if a counterparty
1535 // revokes a state at the same time as the commitment transaction for that state is
1536 // confirmed, and the watchtower receives the block before the user, the user could
1537 // upload a new ChannelMonitor with the revocation secret but the watchtower has
1538 // already processed the block, resulting in the remote_commitment_txn_on_chain entry
1539 // not being generated by the above conditional. Thus, to be safe, we go ahead and
1541 watch_outputs.append(&mut tx.output.clone());
1542 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1544 log_trace!(self, "Got broadcast of non-revoked remote commitment transaction {}", commitment_txid);
1546 macro_rules! check_htlc_fails {
1547 ($txid: expr, $commitment_tx: expr, $id: tt) => {
1548 if let Some(ref latest_outpoints) = self.remote_claimable_outpoints.get($txid) {
1549 $id: for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1550 if let &Some(ref source) = source_option {
1551 // Check if the HTLC is present in the commitment transaction that was
1552 // broadcast, but not if it was below the dust limit, which we should
1553 // fail backwards immediately as there is no way for us to learn the
1554 // payment_preimage.
1555 // Note that if the dust limit were allowed to change between
1556 // commitment transactions we'd want to be check whether *any*
1557 // broadcastable commitment transaction has the HTLC in it, but it
1558 // cannot currently change after channel initialization, so we don't
1560 for &(ref broadcast_htlc, ref broadcast_source) in per_commitment_data.iter() {
1561 if broadcast_htlc.transaction_output_index.is_some() && Some(source) == broadcast_source.as_ref() {
1565 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);
1566 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1567 hash_map::Entry::Occupied(mut entry) => {
1568 let e = entry.get_mut();
1569 e.retain(|ref event| {
1571 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1572 return htlc_update.0 != **source
1577 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1579 hash_map::Entry::Vacant(entry) => {
1580 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1588 if let Some(ref txid) = self.current_remote_commitment_txid {
1589 check_htlc_fails!(txid, "current", 'current_loop);
1591 if let Some(ref txid) = self.prev_remote_commitment_txid {
1592 check_htlc_fails!(txid, "previous", 'prev_loop);
1595 if let Some(revocation_points) = self.their_cur_revocation_points {
1596 let revocation_point_option =
1597 if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1598 else if let Some(point) = revocation_points.2.as_ref() {
1599 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1601 if let Some(revocation_point) = revocation_point_option {
1602 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &self.keys.pubkeys().revocation_basepoint));
1603 let b_htlc_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &self.keys.pubkeys().htlc_basepoint));
1604 let htlc_privkey = ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, revocation_point, &self.keys.htlc_base_key()));
1605 let a_htlc_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &self.their_htlc_base_key));
1606 let local_payment_key = ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, revocation_point, &self.keys.payment_base_key()));
1608 self.broadcasted_remote_payment_script = {
1609 // Note that the Network here is ignored as we immediately drop the address for the
1610 // script_pubkey version
1611 let payment_hash160 = WPubkeyHash::hash(&PublicKey::from_secret_key(&self.secp_ctx, &local_payment_key).serialize());
1612 Some((Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_hash160[..]).into_script(), local_payment_key))
1615 // Then, try to find htlc outputs
1616 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1617 if let Some(transaction_output_index) = htlc.transaction_output_index {
1618 let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1619 if transaction_output_index as usize >= tx.output.len() ||
1620 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
1621 tx.output[transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
1622 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1624 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
1625 let aggregable = if !htlc.offered { false } else { true };
1626 if preimage.is_some() || !htlc.offered {
1627 let witness_data = InputMaterial::RemoteHTLC { witness_script: expected_script, key: htlc_privkey, preimage, amount: htlc.amount_msat / 1000, locktime: htlc.cltv_expiry };
1628 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1635 (claimable_outpoints, (commitment_txid, watch_outputs))
1638 /// Attempts to claim a remote HTLC-Success/HTLC-Timeout's outputs using the revocation key
1639 fn check_spend_remote_htlc(&mut self, tx: &Transaction, commitment_number: u64, height: u32) -> (Vec<ClaimRequest>, Option<(Txid, Vec<TxOut>)>) {
1640 let htlc_txid = tx.txid();
1641 if tx.input.len() != 1 || tx.output.len() != 1 || tx.input[0].witness.len() != 5 {
1642 return (Vec::new(), None)
1645 macro_rules! ignore_error {
1646 ( $thing : expr ) => {
1649 Err(_) => return (Vec::new(), None)
1654 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
1655 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1656 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1657 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.keys.pubkeys().revocation_basepoint));
1658 let revocation_key = ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &self.keys.revocation_base_key()));
1659 let delayed_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &self.their_delayed_payment_base_key));
1660 let redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.our_to_self_delay, &delayed_key);
1662 log_trace!(self, "Remote HTLC broadcast {}:{}", htlc_txid, 0);
1663 let witness_data = InputMaterial::Revoked { witness_script: redeemscript, pubkey: Some(revocation_pubkey), key: revocation_key, is_htlc: false, amount: tx.output[0].value };
1664 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 });
1665 (claimable_outpoints, Some((htlc_txid, tx.output.clone())))
1668 fn broadcast_by_local_state(&self, commitment_tx: &Transaction, local_tx: &LocalSignedTx) -> (Vec<ClaimRequest>, Vec<TxOut>, Option<(Script, SecretKey, Script)>) {
1669 let mut claim_requests = Vec::with_capacity(local_tx.htlc_outputs.len());
1670 let mut watch_outputs = Vec::with_capacity(local_tx.htlc_outputs.len());
1672 let redeemscript = chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.their_to_self_delay, &local_tx.delayed_payment_key);
1673 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()) {
1674 Some((redeemscript.to_v0_p2wsh(), local_delayedkey, redeemscript))
1677 for &(ref htlc, _, _) in local_tx.htlc_outputs.iter() {
1678 if let Some(transaction_output_index) = htlc.transaction_output_index {
1679 claim_requests.push(ClaimRequest { absolute_timelock: ::std::u32::MAX, aggregable: false, outpoint: BitcoinOutPoint { txid: local_tx.txid, vout: transaction_output_index as u32 },
1680 witness_data: InputMaterial::LocalHTLC {
1681 preimage: if !htlc.offered {
1682 if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1683 Some(preimage.clone())
1685 // We can't build an HTLC-Success transaction without the preimage
1689 amount: htlc.amount_msat,
1691 watch_outputs.push(commitment_tx.output[transaction_output_index as usize].clone());
1695 (claim_requests, watch_outputs, broadcasted_local_revokable_script)
1698 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1699 /// revoked using data in local_claimable_outpoints.
1700 /// Should not be used if check_spend_revoked_transaction succeeds.
1701 fn check_spend_local_transaction(&mut self, tx: &Transaction, height: u32) -> (Vec<ClaimRequest>, (Txid, Vec<TxOut>)) {
1702 let commitment_txid = tx.txid();
1703 let mut claim_requests = Vec::new();
1704 let mut watch_outputs = Vec::new();
1706 macro_rules! wait_threshold_conf {
1707 ($height: expr, $source: expr, $commitment_tx: expr, $payment_hash: expr) => {
1708 log_trace!(self, "Failing HTLC with payment_hash {} from {} local commitment tx due to broadcast of transaction, waiting confirmation (at height{})", log_bytes!($payment_hash.0), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1709 match self.onchain_events_waiting_threshold_conf.entry($height + ANTI_REORG_DELAY - 1) {
1710 hash_map::Entry::Occupied(mut entry) => {
1711 let e = entry.get_mut();
1712 e.retain(|ref event| {
1714 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1715 return htlc_update.0 != $source
1720 e.push(OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)});
1722 hash_map::Entry::Vacant(entry) => {
1723 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)}]);
1729 macro_rules! append_onchain_update {
1730 ($updates: expr) => {
1731 claim_requests = $updates.0;
1732 watch_outputs.append(&mut $updates.1);
1733 self.broadcasted_local_revokable_script = $updates.2;
1737 // HTLCs set may differ between last and previous local commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
1738 let mut is_local_tx = false;
1740 if self.current_local_commitment_tx.txid == commitment_txid {
1742 log_trace!(self, "Got latest local commitment tx broadcast, searching for available HTLCs to claim");
1743 let mut res = self.broadcast_by_local_state(tx, &self.current_local_commitment_tx);
1744 append_onchain_update!(res);
1745 } else if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1746 if local_tx.txid == commitment_txid {
1748 log_trace!(self, "Got previous local commitment tx broadcast, searching for available HTLCs to claim");
1749 let mut res = self.broadcast_by_local_state(tx, local_tx);
1750 append_onchain_update!(res);
1754 macro_rules! fail_dust_htlcs_after_threshold_conf {
1755 ($local_tx: expr) => {
1756 for &(ref htlc, _, ref source) in &$local_tx.htlc_outputs {
1757 if htlc.transaction_output_index.is_none() {
1758 if let &Some(ref source) = source {
1759 wait_threshold_conf!(height, source.clone(), "lastest", htlc.payment_hash.clone());
1767 fail_dust_htlcs_after_threshold_conf!(self.current_local_commitment_tx);
1768 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1769 fail_dust_htlcs_after_threshold_conf!(local_tx);
1773 (claim_requests, (commitment_txid, watch_outputs))
1776 /// Used by ChannelManager deserialization to broadcast the latest local state if its copy of
1777 /// the Channel was out-of-date. You may use it to get a broadcastable local toxic tx in case of
1778 /// fallen-behind, i.e when receiving a channel_reestablish with a proof that our remote side knows
1779 /// a higher revocation secret than the local commitment number we are aware of. Broadcasting these
1780 /// transactions are UNSAFE, as they allow remote side to punish you. Nevertheless you may want to
1781 /// broadcast them if remote don't close channel with his higher commitment transaction after a
1782 /// substantial amount of time (a month or even a year) to get back funds. Best may be to contact
1783 /// out-of-band the other node operator to coordinate with him if option is available to you.
1784 /// In any-case, choice is up to the user.
1785 pub fn get_latest_local_commitment_txn(&mut self) -> Vec<Transaction> {
1786 log_trace!(self, "Getting signed latest local commitment transaction!");
1787 self.local_tx_signed = true;
1788 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_local_tx(&self.funding_redeemscript) {
1789 let txid = commitment_tx.txid();
1790 let mut res = vec![commitment_tx];
1791 for htlc in self.current_local_commitment_tx.htlc_outputs.iter() {
1792 if let Some(vout) = htlc.0.transaction_output_index {
1793 let preimage = if !htlc.0.offered {
1794 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1795 // We can't build an HTLC-Success transaction without the preimage
1799 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
1800 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1805 // 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.
1806 // The data will be re-generated and tracked in check_spend_local_transaction if we get a confirmation.
1812 /// Unsafe test-only version of get_latest_local_commitment_txn used by our test framework
1813 /// to bypass LocalCommitmentTransaction state update lockdown after signature and generate
1814 /// revoked commitment transaction.
1816 pub fn unsafe_get_latest_local_commitment_txn(&mut self) -> Vec<Transaction> {
1817 log_trace!(self, "Getting signed copy of latest local commitment transaction!");
1818 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_copy_local_tx(&self.funding_redeemscript) {
1819 let txid = commitment_tx.txid();
1820 let mut res = vec![commitment_tx];
1821 for htlc in self.current_local_commitment_tx.htlc_outputs.iter() {
1822 if let Some(vout) = htlc.0.transaction_output_index {
1823 let preimage = if !htlc.0.offered {
1824 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
1825 // We can't build an HTLC-Success transaction without the preimage
1829 if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
1830 &::bitcoin::OutPoint { txid, vout }, &preimage) {
1840 /// Called when a new block has been connected to the best chain by <SimpleManyChannelMonitor
1841 /// as ChainListener>::block_connected, and should thus generally not be called during normal
1842 /// operation. It is exposed both for users who wish to use ChannelMonitors directly and to
1843 /// simplify rescans that occur at load-time.
1845 /// This is very similar to ChainListener::block_connected itself, but requires an &mut self,
1846 /// and an explicit reference to a transaction broadcaster and fee estimator.
1848 /// Returns a list of new (txid, outputs) pairs which spends of must be watched for. Note that
1849 /// after this call these are also available via get_outputs_to_watch().
1850 pub 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>)>
1851 where B::Target: BroadcasterInterface,
1852 F::Target: FeeEstimator
1854 for tx in txn_matched {
1855 let mut output_val = 0;
1856 for out in tx.output.iter() {
1857 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1858 output_val += out.value;
1859 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1863 log_trace!(self, "Block {} at height {} connected with {} txn matched", block_hash, height, txn_matched.len());
1864 let mut watch_outputs = Vec::new();
1865 let mut claimable_outpoints = Vec::new();
1866 for tx in txn_matched {
1867 if tx.input.len() == 1 {
1868 // Assuming our keys were not leaked (in which case we're screwed no matter what),
1869 // commitment transactions and HTLC transactions will all only ever have one input,
1870 // which is an easy way to filter out any potential non-matching txn for lazy
1872 let prevout = &tx.input[0].previous_output;
1873 if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
1874 if (tx.input[0].sequence >> 8*3) as u8 == 0x80 && (tx.lock_time >> 8*3) as u8 == 0x20 {
1875 let (mut new_outpoints, new_outputs) = self.check_spend_remote_transaction(&tx, height);
1876 if !new_outputs.1.is_empty() {
1877 watch_outputs.push(new_outputs);
1879 if new_outpoints.is_empty() {
1880 let (mut new_outpoints, new_outputs) = self.check_spend_local_transaction(&tx, height);
1881 if !new_outputs.1.is_empty() {
1882 watch_outputs.push(new_outputs);
1884 claimable_outpoints.append(&mut new_outpoints);
1886 claimable_outpoints.append(&mut new_outpoints);
1889 if let Some(&(commitment_number, _)) = self.remote_commitment_txn_on_chain.get(&prevout.txid) {
1890 let (mut new_outpoints, new_outputs_option) = self.check_spend_remote_htlc(&tx, commitment_number, height);
1891 claimable_outpoints.append(&mut new_outpoints);
1892 if let Some(new_outputs) = new_outputs_option {
1893 watch_outputs.push(new_outputs);
1898 // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
1899 // can also be resolved in a few other ways which can have more than one output. Thus,
1900 // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
1901 self.is_resolving_htlc_output(&tx, height);
1903 self.is_paying_spendable_output(&tx, height);
1905 let should_broadcast = self.would_broadcast_at_height(height);
1906 if should_broadcast {
1907 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() }});
1909 if should_broadcast {
1910 if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_local_tx(&self.funding_redeemscript) {
1911 let (mut new_outpoints, new_outputs, _) = self.broadcast_by_local_state(&commitment_tx, &self.current_local_commitment_tx);
1912 if !new_outputs.is_empty() {
1913 watch_outputs.push((self.current_local_commitment_tx.txid.clone(), new_outputs));
1915 claimable_outpoints.append(&mut new_outpoints);
1918 if let Some(events) = self.onchain_events_waiting_threshold_conf.remove(&height) {
1921 OnchainEvent::HTLCUpdate { htlc_update } => {
1922 log_trace!(self, "HTLC {} failure update has got enough confirmations to be passed upstream", log_bytes!((htlc_update.1).0));
1923 self.pending_htlcs_updated.push(HTLCUpdate {
1924 payment_hash: htlc_update.1,
1925 payment_preimage: None,
1926 source: htlc_update.0,
1929 OnchainEvent::MaturingOutput { descriptor } => {
1930 log_trace!(self, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
1931 self.pending_events.push(events::Event::SpendableOutputs {
1932 outputs: vec![descriptor]
1938 self.onchain_tx_handler.block_connected(txn_matched, claimable_outpoints, height, &*broadcaster, &*fee_estimator);
1940 self.last_block_hash = block_hash.clone();
1941 for &(ref txid, ref output_scripts) in watch_outputs.iter() {
1942 self.outputs_to_watch.insert(txid.clone(), output_scripts.iter().map(|o| o.script_pubkey.clone()).collect());
1948 /// Called when a block has been disconnected from the best chain by <SimpleManyChannelMonitor
1949 /// as ChainListener>::block_disconnected, and should thus generally not be called during
1950 /// normal operation. It is exposed both for users who wish to use ChannelMonitors directly and
1951 /// to simplify rescans that occur at load-time.
1953 /// This is very similar to ChainListener::block_disconnected itself, but requires an &mut self,
1954 /// and an explicit reference to a transaction broadcaster and fee estimator.
1955 pub fn block_disconnected<B: Deref, F: Deref>(&mut self, height: u32, block_hash: &BlockHash, broadcaster: B, fee_estimator: F)
1956 where B::Target: BroadcasterInterface,
1957 F::Target: FeeEstimator
1959 log_trace!(self, "Block {} at height {} disconnected", block_hash, height);
1960 if let Some(_) = self.onchain_events_waiting_threshold_conf.remove(&(height + ANTI_REORG_DELAY - 1)) {
1962 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
1963 //- maturing spendable output has transaction paying us has been disconnected
1966 self.onchain_tx_handler.block_disconnected(height, broadcaster, fee_estimator);
1968 self.last_block_hash = block_hash.clone();
1971 pub(super) fn would_broadcast_at_height(&self, height: u32) -> bool {
1972 // We need to consider all HTLCs which are:
1973 // * in any unrevoked remote commitment transaction, as they could broadcast said
1974 // transactions and we'd end up in a race, or
1975 // * are in our latest local commitment transaction, as this is the thing we will
1976 // broadcast if we go on-chain.
1977 // Note that we consider HTLCs which were below dust threshold here - while they don't
1978 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
1979 // to the source, and if we don't fail the channel we will have to ensure that the next
1980 // updates that peer sends us are update_fails, failing the channel if not. It's probably
1981 // easier to just fail the channel as this case should be rare enough anyway.
1982 macro_rules! scan_commitment {
1983 ($htlcs: expr, $local_tx: expr) => {
1984 for ref htlc in $htlcs {
1985 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
1986 // chain with enough room to claim the HTLC without our counterparty being able to
1987 // time out the HTLC first.
1988 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
1989 // concern is being able to claim the corresponding inbound HTLC (on another
1990 // channel) before it expires. In fact, we don't even really care if our
1991 // counterparty here claims such an outbound HTLC after it expired as long as we
1992 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
1993 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
1994 // we give ourselves a few blocks of headroom after expiration before going
1995 // on-chain for an expired HTLC.
1996 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
1997 // from us until we've reached the point where we go on-chain with the
1998 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
1999 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
2000 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
2001 // inbound_cltv == height + CLTV_CLAIM_BUFFER
2002 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
2003 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
2004 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
2005 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
2006 // The final, above, condition is checked for statically in channelmanager
2007 // with CHECK_CLTV_EXPIRY_SANITY_2.
2008 let htlc_outbound = $local_tx == htlc.offered;
2009 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
2010 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
2011 log_info!(self, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
2018 scan_commitment!(self.current_local_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
2020 if let Some(ref txid) = self.current_remote_commitment_txid {
2021 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(txid) {
2022 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2025 if let Some(ref txid) = self.prev_remote_commitment_txid {
2026 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(txid) {
2027 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2034 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a local
2035 /// or remote commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
2036 fn is_resolving_htlc_output(&mut self, tx: &Transaction, height: u32) {
2037 'outer_loop: for input in &tx.input {
2038 let mut payment_data = None;
2039 let revocation_sig_claim = (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && input.witness[1].len() == 33)
2040 || (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && input.witness[1].len() == 33);
2041 let accepted_preimage_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::AcceptedHTLC);
2042 let offered_preimage_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC);
2044 macro_rules! log_claim {
2045 ($tx_info: expr, $local_tx: expr, $htlc: expr, $source_avail: expr) => {
2046 // We found the output in question, but aren't failing it backwards
2047 // as we have no corresponding source and no valid remote commitment txid
2048 // to try a weak source binding with same-hash, same-value still-valid offered HTLC.
2049 // This implies either it is an inbound HTLC or an outbound HTLC on a revoked transaction.
2050 let outbound_htlc = $local_tx == $htlc.offered;
2051 if ($local_tx && revocation_sig_claim) ||
2052 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
2053 log_error!(self, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
2054 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2055 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2056 if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back" });
2058 log_info!(self, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
2059 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2060 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2061 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
2066 macro_rules! check_htlc_valid_remote {
2067 ($remote_txid: expr, $htlc_output: expr) => {
2068 if let Some(txid) = $remote_txid {
2069 for &(ref pending_htlc, ref pending_source) in self.remote_claimable_outpoints.get(&txid).unwrap() {
2070 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
2071 if let &Some(ref source) = pending_source {
2072 log_claim!("revoked remote commitment tx", false, pending_htlc, true);
2073 payment_data = Some(((**source).clone(), $htlc_output.payment_hash));
2082 macro_rules! scan_commitment {
2083 ($htlcs: expr, $tx_info: expr, $local_tx: expr) => {
2084 for (ref htlc_output, source_option) in $htlcs {
2085 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
2086 if let Some(ref source) = source_option {
2087 log_claim!($tx_info, $local_tx, htlc_output, true);
2088 // We have a resolution of an HTLC either from one of our latest
2089 // local commitment transactions or an unrevoked remote commitment
2090 // transaction. This implies we either learned a preimage, the HTLC
2091 // has timed out, or we screwed up. In any case, we should now
2092 // resolve the source HTLC with the original sender.
2093 payment_data = Some(((*source).clone(), htlc_output.payment_hash));
2094 } else if !$local_tx {
2095 check_htlc_valid_remote!(self.current_remote_commitment_txid, htlc_output);
2096 if payment_data.is_none() {
2097 check_htlc_valid_remote!(self.prev_remote_commitment_txid, htlc_output);
2100 if payment_data.is_none() {
2101 log_claim!($tx_info, $local_tx, htlc_output, false);
2102 continue 'outer_loop;
2109 if input.previous_output.txid == self.current_local_commitment_tx.txid {
2110 scan_commitment!(self.current_local_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2111 "our latest local commitment tx", true);
2113 if let Some(ref prev_local_signed_commitment_tx) = self.prev_local_signed_commitment_tx {
2114 if input.previous_output.txid == prev_local_signed_commitment_tx.txid {
2115 scan_commitment!(prev_local_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2116 "our previous local commitment tx", true);
2119 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(&input.previous_output.txid) {
2120 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
2121 "remote commitment tx", false);
2124 // Check that scan_commitment, above, decided there is some source worth relaying an
2125 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
2126 if let Some((source, payment_hash)) = payment_data {
2127 let mut payment_preimage = PaymentPreimage([0; 32]);
2128 if accepted_preimage_claim {
2129 if !self.pending_htlcs_updated.iter().any(|update| update.source == source) {
2130 payment_preimage.0.copy_from_slice(&input.witness[3]);
2131 self.pending_htlcs_updated.push(HTLCUpdate {
2133 payment_preimage: Some(payment_preimage),
2137 } else if offered_preimage_claim {
2138 if !self.pending_htlcs_updated.iter().any(|update| update.source == source) {
2139 payment_preimage.0.copy_from_slice(&input.witness[1]);
2140 self.pending_htlcs_updated.push(HTLCUpdate {
2142 payment_preimage: Some(payment_preimage),
2147 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);
2148 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2149 hash_map::Entry::Occupied(mut entry) => {
2150 let e = entry.get_mut();
2151 e.retain(|ref event| {
2153 OnchainEvent::HTLCUpdate { ref htlc_update } => {
2154 return htlc_update.0 != source
2159 e.push(OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)});
2161 hash_map::Entry::Vacant(entry) => {
2162 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)}]);
2170 /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
2171 fn is_paying_spendable_output(&mut self, tx: &Transaction, height: u32) {
2172 let mut spendable_output = None;
2173 for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
2174 if outp.script_pubkey == self.destination_script {
2175 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2176 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2177 output: outp.clone(),
2180 } else if let Some(ref broadcasted_local_revokable_script) = self.broadcasted_local_revokable_script {
2181 if broadcasted_local_revokable_script.0 == outp.script_pubkey {
2182 spendable_output = Some(SpendableOutputDescriptor::DynamicOutputP2WSH {
2183 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2184 key: broadcasted_local_revokable_script.1,
2185 witness_script: broadcasted_local_revokable_script.2.clone(),
2186 to_self_delay: self.their_to_self_delay,
2187 output: outp.clone(),
2191 } else if let Some(ref broadcasted_remote_payment_script) = self.broadcasted_remote_payment_script {
2192 if broadcasted_remote_payment_script.0 == outp.script_pubkey {
2193 spendable_output = Some(SpendableOutputDescriptor::DynamicOutputP2WPKH {
2194 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2195 key: broadcasted_remote_payment_script.1,
2196 output: outp.clone(),
2200 } else if outp.script_pubkey == self.shutdown_script {
2201 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2202 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2203 output: outp.clone(),
2207 if let Some(spendable_output) = spendable_output {
2208 log_trace!(self, "Maturing {} until {}", log_spendable!(spendable_output), height + ANTI_REORG_DELAY - 1);
2209 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2210 hash_map::Entry::Occupied(mut entry) => {
2211 let e = entry.get_mut();
2212 e.push(OnchainEvent::MaturingOutput { descriptor: spendable_output });
2214 hash_map::Entry::Vacant(entry) => {
2215 entry.insert(vec![OnchainEvent::MaturingOutput { descriptor: spendable_output }]);
2222 const MAX_ALLOC_SIZE: usize = 64*1024;
2224 impl<ChanSigner: ChannelKeys + Readable> ReadableArgs<Arc<Logger>> for (BlockHash, ChannelMonitor<ChanSigner>) {
2225 fn read<R: ::std::io::Read>(reader: &mut R, logger: Arc<Logger>) -> Result<Self, DecodeError> {
2226 macro_rules! unwrap_obj {
2230 Err(_) => return Err(DecodeError::InvalidValue),
2235 let _ver: u8 = Readable::read(reader)?;
2236 let min_ver: u8 = Readable::read(reader)?;
2237 if min_ver > SERIALIZATION_VERSION {
2238 return Err(DecodeError::UnknownVersion);
2241 let latest_update_id: u64 = Readable::read(reader)?;
2242 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
2244 let destination_script = Readable::read(reader)?;
2245 let broadcasted_local_revokable_script = match <u8 as Readable>::read(reader)? {
2247 let revokable_address = Readable::read(reader)?;
2248 let local_delayedkey = Readable::read(reader)?;
2249 let revokable_script = Readable::read(reader)?;
2250 Some((revokable_address, local_delayedkey, revokable_script))
2253 _ => return Err(DecodeError::InvalidValue),
2255 let broadcasted_remote_payment_script = match <u8 as Readable>::read(reader)? {
2257 let payment_address = Readable::read(reader)?;
2258 let payment_key = Readable::read(reader)?;
2259 Some((payment_address, payment_key))
2262 _ => return Err(DecodeError::InvalidValue),
2264 let shutdown_script = Readable::read(reader)?;
2266 let keys = Readable::read(reader)?;
2267 // Technically this can fail and serialize fail a round-trip, but only for serialization of
2268 // barely-init'd ChannelMonitors that we can't do anything with.
2269 let outpoint = OutPoint {
2270 txid: Readable::read(reader)?,
2271 index: Readable::read(reader)?,
2273 let funding_info = (outpoint, Readable::read(reader)?);
2274 let current_remote_commitment_txid = Readable::read(reader)?;
2275 let prev_remote_commitment_txid = Readable::read(reader)?;
2277 let their_htlc_base_key = Readable::read(reader)?;
2278 let their_delayed_payment_base_key = Readable::read(reader)?;
2279 let funding_redeemscript = Readable::read(reader)?;
2280 let channel_value_satoshis = Readable::read(reader)?;
2282 let their_cur_revocation_points = {
2283 let first_idx = <U48 as Readable>::read(reader)?.0;
2287 let first_point = Readable::read(reader)?;
2288 let second_point_slice: [u8; 33] = Readable::read(reader)?;
2289 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
2290 Some((first_idx, first_point, None))
2292 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
2297 let our_to_self_delay: u16 = Readable::read(reader)?;
2298 let their_to_self_delay: u16 = Readable::read(reader)?;
2300 let commitment_secrets = Readable::read(reader)?;
2302 macro_rules! read_htlc_in_commitment {
2305 let offered: bool = Readable::read(reader)?;
2306 let amount_msat: u64 = Readable::read(reader)?;
2307 let cltv_expiry: u32 = Readable::read(reader)?;
2308 let payment_hash: PaymentHash = Readable::read(reader)?;
2309 let transaction_output_index: Option<u32> = Readable::read(reader)?;
2311 HTLCOutputInCommitment {
2312 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
2318 let remote_claimable_outpoints_len: u64 = Readable::read(reader)?;
2319 let mut remote_claimable_outpoints = HashMap::with_capacity(cmp::min(remote_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
2320 for _ in 0..remote_claimable_outpoints_len {
2321 let txid: Txid = Readable::read(reader)?;
2322 let htlcs_count: u64 = Readable::read(reader)?;
2323 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
2324 for _ in 0..htlcs_count {
2325 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
2327 if let Some(_) = remote_claimable_outpoints.insert(txid, htlcs) {
2328 return Err(DecodeError::InvalidValue);
2332 let remote_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
2333 let mut remote_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(remote_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
2334 for _ in 0..remote_commitment_txn_on_chain_len {
2335 let txid: Txid = Readable::read(reader)?;
2336 let commitment_number = <U48 as Readable>::read(reader)?.0;
2337 let outputs_count = <u64 as Readable>::read(reader)?;
2338 let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 8));
2339 for _ in 0..outputs_count {
2340 outputs.push(Readable::read(reader)?);
2342 if let Some(_) = remote_commitment_txn_on_chain.insert(txid, (commitment_number, outputs)) {
2343 return Err(DecodeError::InvalidValue);
2347 let remote_hash_commitment_number_len: u64 = Readable::read(reader)?;
2348 let mut remote_hash_commitment_number = HashMap::with_capacity(cmp::min(remote_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
2349 for _ in 0..remote_hash_commitment_number_len {
2350 let payment_hash: PaymentHash = Readable::read(reader)?;
2351 let commitment_number = <U48 as Readable>::read(reader)?.0;
2352 if let Some(_) = remote_hash_commitment_number.insert(payment_hash, commitment_number) {
2353 return Err(DecodeError::InvalidValue);
2357 macro_rules! read_local_tx {
2360 let txid = Readable::read(reader)?;
2361 let revocation_key = Readable::read(reader)?;
2362 let a_htlc_key = Readable::read(reader)?;
2363 let b_htlc_key = Readable::read(reader)?;
2364 let delayed_payment_key = Readable::read(reader)?;
2365 let per_commitment_point = Readable::read(reader)?;
2366 let feerate_per_kw: u64 = Readable::read(reader)?;
2368 let htlcs_len: u64 = Readable::read(reader)?;
2369 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_len as usize, MAX_ALLOC_SIZE / 128));
2370 for _ in 0..htlcs_len {
2371 let htlc = read_htlc_in_commitment!();
2372 let sigs = match <u8 as Readable>::read(reader)? {
2374 1 => Some(Readable::read(reader)?),
2375 _ => return Err(DecodeError::InvalidValue),
2377 htlcs.push((htlc, sigs, Readable::read(reader)?));
2382 revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, per_commitment_point, feerate_per_kw,
2389 let prev_local_signed_commitment_tx = match <u8 as Readable>::read(reader)? {
2392 Some(read_local_tx!())
2394 _ => return Err(DecodeError::InvalidValue),
2396 let current_local_commitment_tx = read_local_tx!();
2398 let current_remote_commitment_number = <U48 as Readable>::read(reader)?.0;
2399 let current_local_commitment_number = <U48 as Readable>::read(reader)?.0;
2401 let payment_preimages_len: u64 = Readable::read(reader)?;
2402 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
2403 for _ in 0..payment_preimages_len {
2404 let preimage: PaymentPreimage = Readable::read(reader)?;
2405 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2406 if let Some(_) = payment_preimages.insert(hash, preimage) {
2407 return Err(DecodeError::InvalidValue);
2411 let pending_htlcs_updated_len: u64 = Readable::read(reader)?;
2412 let mut pending_htlcs_updated = Vec::with_capacity(cmp::min(pending_htlcs_updated_len as usize, MAX_ALLOC_SIZE / (32 + 8*3)));
2413 for _ in 0..pending_htlcs_updated_len {
2414 pending_htlcs_updated.push(Readable::read(reader)?);
2417 let pending_events_len: u64 = Readable::read(reader)?;
2418 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<events::Event>()));
2419 for _ in 0..pending_events_len {
2420 if let Some(event) = MaybeReadable::read(reader)? {
2421 pending_events.push(event);
2425 let last_block_hash: BlockHash = Readable::read(reader)?;
2427 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
2428 let mut onchain_events_waiting_threshold_conf = HashMap::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
2429 for _ in 0..waiting_threshold_conf_len {
2430 let height_target = Readable::read(reader)?;
2431 let events_len: u64 = Readable::read(reader)?;
2432 let mut events = Vec::with_capacity(cmp::min(events_len as usize, MAX_ALLOC_SIZE / 128));
2433 for _ in 0..events_len {
2434 let ev = match <u8 as Readable>::read(reader)? {
2436 let htlc_source = Readable::read(reader)?;
2437 let hash = Readable::read(reader)?;
2438 OnchainEvent::HTLCUpdate {
2439 htlc_update: (htlc_source, hash)
2443 let descriptor = Readable::read(reader)?;
2444 OnchainEvent::MaturingOutput {
2448 _ => return Err(DecodeError::InvalidValue),
2452 onchain_events_waiting_threshold_conf.insert(height_target, events);
2455 let outputs_to_watch_len: u64 = Readable::read(reader)?;
2456 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>>())));
2457 for _ in 0..outputs_to_watch_len {
2458 let txid = Readable::read(reader)?;
2459 let outputs_len: u64 = Readable::read(reader)?;
2460 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Script>()));
2461 for _ in 0..outputs_len {
2462 outputs.push(Readable::read(reader)?);
2464 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
2465 return Err(DecodeError::InvalidValue);
2468 let onchain_tx_handler = ReadableArgs::read(reader, logger.clone())?;
2470 let lockdown_from_offchain = Readable::read(reader)?;
2471 let local_tx_signed = Readable::read(reader)?;
2473 Ok((last_block_hash.clone(), ChannelMonitor {
2475 commitment_transaction_number_obscure_factor,
2478 broadcasted_local_revokable_script,
2479 broadcasted_remote_payment_script,
2484 current_remote_commitment_txid,
2485 prev_remote_commitment_txid,
2487 their_htlc_base_key,
2488 their_delayed_payment_base_key,
2489 funding_redeemscript,
2490 channel_value_satoshis,
2491 their_cur_revocation_points,
2494 their_to_self_delay,
2497 remote_claimable_outpoints,
2498 remote_commitment_txn_on_chain,
2499 remote_hash_commitment_number,
2501 prev_local_signed_commitment_tx,
2502 current_local_commitment_tx,
2503 current_remote_commitment_number,
2504 current_local_commitment_number,
2507 pending_htlcs_updated,
2510 onchain_events_waiting_threshold_conf,
2515 lockdown_from_offchain,
2519 secp_ctx: Secp256k1::new(),
2527 use bitcoin::blockdata::script::{Script, Builder};
2528 use bitcoin::blockdata::opcodes;
2529 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, SigHashType};
2530 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
2531 use bitcoin::util::bip143;
2532 use bitcoin::hashes::Hash;
2533 use bitcoin::hashes::sha256::Hash as Sha256;
2534 use bitcoin::hashes::hex::FromHex;
2535 use bitcoin::hash_types::Txid;
2537 use chain::transaction::OutPoint;
2538 use ln::channelmanager::{PaymentPreimage, PaymentHash};
2539 use ln::channelmonitor::ChannelMonitor;
2540 use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
2542 use ln::chan_utils::{HTLCOutputInCommitment, LocalCommitmentTransaction};
2543 use util::test_utils::TestLogger;
2544 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
2545 use bitcoin::secp256k1::Secp256k1;
2546 use rand::{thread_rng,Rng};
2548 use chain::keysinterface::InMemoryChannelKeys;
2551 fn test_prune_preimages() {
2552 let secp_ctx = Secp256k1::new();
2553 let logger = Arc::new(TestLogger::new());
2555 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
2556 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2558 let mut preimages = Vec::new();
2560 let mut rng = thread_rng();
2562 let mut preimage = PaymentPreimage([0; 32]);
2563 rng.fill_bytes(&mut preimage.0[..]);
2564 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2565 preimages.push((preimage, hash));
2569 macro_rules! preimages_slice_to_htlc_outputs {
2570 ($preimages_slice: expr) => {
2572 let mut res = Vec::new();
2573 for (idx, preimage) in $preimages_slice.iter().enumerate() {
2574 res.push((HTLCOutputInCommitment {
2578 payment_hash: preimage.1.clone(),
2579 transaction_output_index: Some(idx as u32),
2586 macro_rules! preimages_to_local_htlcs {
2587 ($preimages_slice: expr) => {
2589 let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2590 let res: Vec<_> = inp.drain(..).map(|e| { (e.0, None, e.1) }).collect();
2596 macro_rules! test_preimages_exist {
2597 ($preimages_slice: expr, $monitor: expr) => {
2598 for preimage in $preimages_slice {
2599 assert!($monitor.payment_preimages.contains_key(&preimage.1));
2604 let keys = InMemoryChannelKeys::new(
2606 SecretKey::from_slice(&[41; 32]).unwrap(),
2607 SecretKey::from_slice(&[41; 32]).unwrap(),
2608 SecretKey::from_slice(&[41; 32]).unwrap(),
2609 SecretKey::from_slice(&[41; 32]).unwrap(),
2610 SecretKey::from_slice(&[41; 32]).unwrap(),
2615 // Prune with one old state and a local commitment tx holding a few overlaps with the
2617 let mut monitor = ChannelMonitor::new(keys,
2618 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()), 0, &Script::new(),
2619 (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
2620 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
2621 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
2622 10, Script::new(), 46, 0, LocalCommitmentTransaction::dummy(), logger.clone());
2624 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..10])).unwrap();
2625 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key);
2626 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key);
2627 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key);
2628 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key);
2629 for &(ref preimage, ref hash) in preimages.iter() {
2630 monitor.provide_payment_preimage(hash, preimage);
2633 // Now provide a secret, pruning preimages 10-15
2634 let mut secret = [0; 32];
2635 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2636 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2637 assert_eq!(monitor.payment_preimages.len(), 15);
2638 test_preimages_exist!(&preimages[0..10], monitor);
2639 test_preimages_exist!(&preimages[15..20], monitor);
2641 // Now provide a further secret, pruning preimages 15-17
2642 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2643 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2644 assert_eq!(monitor.payment_preimages.len(), 13);
2645 test_preimages_exist!(&preimages[0..10], monitor);
2646 test_preimages_exist!(&preimages[17..20], monitor);
2648 // Now update local commitment tx info, pruning only element 18 as we still care about the
2649 // previous commitment tx's preimages too
2650 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..5])).unwrap();
2651 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2652 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2653 assert_eq!(monitor.payment_preimages.len(), 12);
2654 test_preimages_exist!(&preimages[0..10], monitor);
2655 test_preimages_exist!(&preimages[18..20], monitor);
2657 // But if we do it again, we'll prune 5-10
2658 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), preimages_to_local_htlcs!(preimages[0..3])).unwrap();
2659 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2660 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2661 assert_eq!(monitor.payment_preimages.len(), 5);
2662 test_preimages_exist!(&preimages[0..5], monitor);
2666 fn test_claim_txn_weight_computation() {
2667 // We test Claim txn weight, knowing that we want expected weigth and
2668 // not actual case to avoid sigs and time-lock delays hell variances.
2670 let secp_ctx = Secp256k1::new();
2671 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
2672 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
2673 let mut sum_actual_sigs = 0;
2675 macro_rules! sign_input {
2676 ($sighash_parts: expr, $input: expr, $idx: expr, $amount: expr, $input_type: expr, $sum_actual_sigs: expr) => {
2677 let htlc = HTLCOutputInCommitment {
2678 offered: if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::OfferedHTLC { true } else { false },
2680 cltv_expiry: 2 << 16,
2681 payment_hash: PaymentHash([1; 32]),
2682 transaction_output_index: Some($idx),
2684 let redeem_script = if *$input_type == InputDescriptors::RevokedOutput { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &pubkey, &pubkey, &pubkey) };
2685 let sighash = hash_to_message!(&$sighash_parts.sighash_all(&$input, &redeem_script, $amount)[..]);
2686 let sig = secp_ctx.sign(&sighash, &privkey);
2687 $input.witness.push(sig.serialize_der().to_vec());
2688 $input.witness[0].push(SigHashType::All as u8);
2689 sum_actual_sigs += $input.witness[0].len();
2690 if *$input_type == InputDescriptors::RevokedOutput {
2691 $input.witness.push(vec!(1));
2692 } else if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::RevokedReceivedHTLC {
2693 $input.witness.push(pubkey.clone().serialize().to_vec());
2694 } else if *$input_type == InputDescriptors::ReceivedHTLC {
2695 $input.witness.push(vec![0]);
2697 $input.witness.push(PaymentPreimage([1; 32]).0.to_vec());
2699 $input.witness.push(redeem_script.into_bytes());
2700 println!("witness[0] {}", $input.witness[0].len());
2701 println!("witness[1] {}", $input.witness[1].len());
2702 println!("witness[2] {}", $input.witness[2].len());
2706 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
2707 let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
2709 // Justice tx with 1 to_local, 2 revoked offered HTLCs, 1 revoked received HTLCs
2710 let mut claim_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2712 claim_tx.input.push(TxIn {
2713 previous_output: BitcoinOutPoint {
2717 script_sig: Script::new(),
2718 sequence: 0xfffffffd,
2719 witness: Vec::new(),
2722 claim_tx.output.push(TxOut {
2723 script_pubkey: script_pubkey.clone(),
2726 let base_weight = claim_tx.get_weight();
2727 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2728 let inputs_des = vec![InputDescriptors::RevokedOutput, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedReceivedHTLC];
2729 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2730 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2732 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));
2734 // Claim tx with 1 offered HTLCs, 3 received HTLCs
2735 claim_tx.input.clear();
2736 sum_actual_sigs = 0;
2738 claim_tx.input.push(TxIn {
2739 previous_output: BitcoinOutPoint {
2743 script_sig: Script::new(),
2744 sequence: 0xfffffffd,
2745 witness: Vec::new(),
2748 let base_weight = claim_tx.get_weight();
2749 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2750 let inputs_des = vec![InputDescriptors::OfferedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC];
2751 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2752 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2754 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));
2756 // Justice tx with 1 revoked HTLC-Success tx output
2757 claim_tx.input.clear();
2758 sum_actual_sigs = 0;
2759 claim_tx.input.push(TxIn {
2760 previous_output: BitcoinOutPoint {
2764 script_sig: Script::new(),
2765 sequence: 0xfffffffd,
2766 witness: Vec::new(),
2768 let base_weight = claim_tx.get_weight();
2769 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2770 let inputs_des = vec![InputDescriptors::RevokedOutput];
2771 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2772 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2774 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));
2777 // Further testing is done in the ChannelManager integration tests.