1 //! The logic to monitor for on-chain transactions and create the relevant claim responses lives
4 //! ChannelMonitor objects are generated by ChannelManager in response to relevant
5 //! messages/actions, and MUST be persisted to disk (and, preferably, remotely) before progress can
6 //! be made in responding to certain messages, see ManyChannelMonitor for more.
8 //! Note that ChannelMonitors are an important part of the lightning trust model and a copy of the
9 //! latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date
10 //! ChannelMonitors should do so). Thus, if you're building rust-lightning into an HSM or other
11 //! security-domain-separated system design, you should consider having multiple paths for
12 //! ChannelMonitors to get out of the HSM and onto monitoring devices.
14 use bitcoin::blockdata::block::BlockHeader;
15 use bitcoin::blockdata::transaction::{TxOut,Transaction};
16 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
17 use bitcoin::blockdata::script::{Script, Builder};
18 use bitcoin::blockdata::opcodes;
19 use bitcoin::consensus::encode;
20 use bitcoin::util::hash::BitcoinHash;
22 use bitcoin_hashes::Hash;
23 use bitcoin_hashes::sha256::Hash as Sha256;
24 use bitcoin_hashes::hash160::Hash as Hash160;
25 use bitcoin_hashes::sha256d::Hash as Sha256dHash;
27 use secp256k1::{Secp256k1,Signature};
28 use secp256k1::key::{SecretKey,PublicKey};
31 use ln::msgs::DecodeError;
33 use ln::chan_utils::{CounterpartyCommitmentSecrets, HTLCOutputInCommitment, LocalCommitmentTransaction, HTLCType};
34 use ln::channelmanager::{HTLCSource, PaymentPreimage, PaymentHash};
35 use ln::onchaintx::OnchainTxHandler;
36 use chain::chaininterface::{ChainListener, ChainWatchInterface, BroadcasterInterface, FeeEstimator};
37 use chain::transaction::OutPoint;
38 use chain::keysinterface::{SpendableOutputDescriptor, ChannelKeys};
39 use util::logger::Logger;
40 use util::ser::{ReadableArgs, Readable, MaybeReadable, Writer, Writeable, U48};
41 use util::{byte_utils, events};
43 use std::collections::{HashMap, hash_map};
44 use std::sync::{Arc,Mutex};
45 use std::{hash,cmp, mem};
48 /// An update generated by the underlying Channel itself which contains some new information the
49 /// ChannelMonitor should be made aware of.
50 #[cfg_attr(test, derive(PartialEq))]
53 pub struct ChannelMonitorUpdate {
54 pub(super) updates: Vec<ChannelMonitorUpdateStep>,
55 /// The sequence number of this update. Updates *must* be replayed in-order according to this
56 /// sequence number (and updates may panic if they are not). The update_id values are strictly
57 /// increasing and increase by one for each new update.
59 /// This sequence number is also used to track up to which points updates which returned
60 /// ChannelMonitorUpdateErr::TemporaryFailure have been applied to all copies of a given
61 /// ChannelMonitor when ChannelManager::channel_monitor_updated is called.
65 impl Writeable for ChannelMonitorUpdate {
66 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
67 self.update_id.write(w)?;
68 (self.updates.len() as u64).write(w)?;
69 for update_step in self.updates.iter() {
70 update_step.write(w)?;
75 impl Readable for ChannelMonitorUpdate {
76 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
77 let update_id: u64 = Readable::read(r)?;
78 let len: u64 = Readable::read(r)?;
79 let mut updates = Vec::with_capacity(cmp::min(len as usize, MAX_ALLOC_SIZE / ::std::mem::size_of::<ChannelMonitorUpdateStep>()));
81 updates.push(Readable::read(r)?);
83 Ok(Self { update_id, updates })
87 /// An error enum representing a failure to persist a channel monitor update.
89 pub enum ChannelMonitorUpdateErr {
90 /// Used to indicate a temporary failure (eg connection to a watchtower or remote backup of
91 /// our state failed, but is expected to succeed at some point in the future).
93 /// Such a failure will "freeze" a channel, preventing us from revoking old states or
94 /// submitting new commitment transactions to the remote party. Once the update(s) which failed
95 /// have been successfully applied, ChannelManager::channel_monitor_updated can be used to
96 /// restore the channel to an operational state.
98 /// Note that a given ChannelManager will *never* re-generate a given ChannelMonitorUpdate. If
99 /// you return a TemporaryFailure you must ensure that it is written to disk safely before
100 /// writing out the latest ChannelManager state.
102 /// Even when a channel has been "frozen" updates to the ChannelMonitor can continue to occur
103 /// (eg if an inbound HTLC which we forwarded was claimed upstream resulting in us attempting
104 /// to claim it on this channel) and those updates must be applied wherever they can be. At
105 /// least one such updated ChannelMonitor must be persisted otherwise PermanentFailure should
106 /// be returned to get things on-chain ASAP using only the in-memory copy. Obviously updates to
107 /// the channel which would invalidate previous ChannelMonitors are not made when a channel has
110 /// Note that even if updates made after TemporaryFailure succeed you must still call
111 /// channel_monitor_updated to ensure you have the latest monitor and re-enable normal channel
114 /// Note that the update being processed here will not be replayed for you when you call
115 /// ChannelManager::channel_monitor_updated, so you must store the update itself along
116 /// with the persisted ChannelMonitor on your own local disk prior to returning a
117 /// TemporaryFailure. You may, of course, employ a journaling approach, storing only the
118 /// ChannelMonitorUpdate on disk without updating the monitor itself, replaying the journal at
121 /// For deployments where a copy of ChannelMonitors and other local state are backed up in a
122 /// remote location (with local copies persisted immediately), it is anticipated that all
123 /// updates will return TemporaryFailure until the remote copies could be updated.
125 /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
126 /// different watchtower and cannot update with all watchtowers that were previously informed
127 /// of this channel). This will force-close the channel in question (which will generate one
128 /// final ChannelMonitorUpdate which must be delivered to at least one ChannelMonitor copy).
130 /// Should also be used to indicate a failure to update the local persisted copy of the channel
135 /// General Err type for ChannelMonitor actions. Generally, this implies that the data provided is
136 /// inconsistent with the ChannelMonitor being called. eg for ChannelMonitor::update_monitor this
137 /// means you tried to update a monitor for a different channel or the ChannelMonitorUpdate was
139 /// Contains a human-readable error message.
141 pub struct MonitorUpdateError(pub &'static str);
143 /// Simple structure send back by ManyChannelMonitor in case of HTLC detected onchain from a
144 /// forward channel and from which info are needed to update HTLC in a backward channel.
145 #[derive(Clone, PartialEq)]
146 pub struct HTLCUpdate {
147 pub(super) payment_hash: PaymentHash,
148 pub(super) payment_preimage: Option<PaymentPreimage>,
149 pub(super) source: HTLCSource
151 impl_writeable!(HTLCUpdate, 0, { payment_hash, payment_preimage, source });
153 /// Simple trait indicating ability to track a set of ChannelMonitors and multiplex events between
154 /// them. Generally should be implemented by keeping a local SimpleManyChannelMonitor and passing
155 /// events to it, while also taking any add/update_monitor events and passing them to some remote
158 /// In general, you must always have at least one local copy in memory, which must never fail to
159 /// update (as it is responsible for broadcasting the latest state in case the channel is closed),
160 /// and then persist it to various on-disk locations. If, for some reason, the in-memory copy fails
161 /// to update (eg out-of-memory or some other condition), you must immediately shut down without
162 /// taking any further action such as writing the current state to disk. This should likely be
163 /// accomplished via panic!() or abort().
165 /// Note that any updates to a channel's monitor *must* be applied to each instance of the
166 /// channel's monitor everywhere (including remote watchtowers) *before* this function returns. If
167 /// an update occurs and a remote watchtower is left with old state, it may broadcast transactions
168 /// which we have revoked, allowing our counterparty to claim all funds in the channel!
170 /// User needs to notify implementors of ManyChannelMonitor when a new block is connected or
171 /// disconnected using their `block_connected` and `block_disconnected` methods. However, rather
172 /// than calling these methods directly, the user should register implementors as listeners to the
173 /// BlockNotifier and call the BlockNotifier's `block_(dis)connected` methods, which will notify
174 /// all registered listeners in one go.
175 pub trait ManyChannelMonitor<ChanSigner: ChannelKeys>: Send + Sync {
176 /// Adds a monitor for the given `funding_txo`.
178 /// Implementer must also ensure that the funding_txo txid *and* outpoint are registered with
179 /// any relevant ChainWatchInterfaces such that the provided monitor receives block_connected
180 /// callbacks with the funding transaction, or any spends of it.
182 /// Further, the implementer must also ensure that each output returned in
183 /// monitor.get_outputs_to_watch() is registered to ensure that the provided monitor learns about
184 /// any spends of any of the outputs.
186 /// Any spends of outputs which should have been registered which aren't passed to
187 /// ChannelMonitors via block_connected may result in FUNDS LOSS.
188 fn add_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor<ChanSigner>) -> Result<(), ChannelMonitorUpdateErr>;
190 /// Updates a monitor for the given `funding_txo`.
192 /// Implementer must also ensure that the funding_txo txid *and* outpoint are registered with
193 /// any relevant ChainWatchInterfaces such that the provided monitor receives block_connected
194 /// callbacks with the funding transaction, or any spends of it.
196 /// Further, the implementer must also ensure that each output returned in
197 /// monitor.get_watch_outputs() is registered to ensure that the provided monitor learns about
198 /// any spends of any of the outputs.
200 /// Any spends of outputs which should have been registered which aren't passed to
201 /// ChannelMonitors via block_connected may result in FUNDS LOSS.
202 fn update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr>;
204 /// Used by ChannelManager to get list of HTLC resolved onchain and which needed to be updated
205 /// with success or failure.
207 /// You should probably just call through to
208 /// ChannelMonitor::get_and_clear_pending_htlcs_updated() for each ChannelMonitor and return
210 fn get_and_clear_pending_htlcs_updated(&self) -> Vec<HTLCUpdate>;
213 /// A simple implementation of a ManyChannelMonitor and ChainListener. Can be used to create a
214 /// watchtower or watch our own channels.
216 /// Note that you must provide your own key by which to refer to channels.
218 /// If you're accepting remote monitors (ie are implementing a watchtower), you must verify that
219 /// users cannot overwrite a given channel by providing a duplicate key. ie you should probably
220 /// index by a PublicKey which is required to sign any updates.
222 /// If you're using this for local monitoring of your own channels, you probably want to use
223 /// `OutPoint` as the key, which will give you a ManyChannelMonitor implementation.
224 pub struct SimpleManyChannelMonitor<Key, ChanSigner: ChannelKeys, T: Deref, F: Deref>
225 where T::Target: BroadcasterInterface,
226 F::Target: FeeEstimator
228 #[cfg(test)] // Used in ChannelManager tests to manipulate channels directly
229 pub monitors: Mutex<HashMap<Key, ChannelMonitor<ChanSigner>>>,
231 monitors: Mutex<HashMap<Key, ChannelMonitor<ChanSigner>>>,
232 chain_monitor: Arc<ChainWatchInterface>,
238 impl<'a, Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys, T: Deref + Sync + Send, F: Deref + Sync + Send>
239 ChainListener for SimpleManyChannelMonitor<Key, ChanSigner, T, F>
240 where T::Target: BroadcasterInterface,
241 F::Target: FeeEstimator
243 fn block_connected(&self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], _indexes_of_txn_matched: &[u32]) {
244 let block_hash = header.bitcoin_hash();
246 let mut monitors = self.monitors.lock().unwrap();
247 for monitor in monitors.values_mut() {
248 let txn_outputs = monitor.block_connected(txn_matched, height, &block_hash, &*self.broadcaster, &*self.fee_estimator);
250 for (ref txid, ref outputs) in txn_outputs {
251 for (idx, output) in outputs.iter().enumerate() {
252 self.chain_monitor.install_watch_outpoint((txid.clone(), idx as u32), &output.script_pubkey);
259 fn block_disconnected(&self, header: &BlockHeader, disconnected_height: u32) {
260 let block_hash = header.bitcoin_hash();
261 let mut monitors = self.monitors.lock().unwrap();
262 for monitor in monitors.values_mut() {
263 monitor.block_disconnected(disconnected_height, &block_hash, &*self.broadcaster, &*self.fee_estimator);
268 impl<Key : Send + cmp::Eq + hash::Hash + 'static, ChanSigner: ChannelKeys, T: Deref, F: Deref> SimpleManyChannelMonitor<Key, ChanSigner, T, F>
269 where T::Target: BroadcasterInterface,
270 F::Target: FeeEstimator
272 /// Creates a new object which can be used to monitor several channels given the chain
273 /// interface with which to register to receive notifications.
274 pub fn new(chain_monitor: Arc<ChainWatchInterface>, broadcaster: T, logger: Arc<Logger>, feeest: F) -> SimpleManyChannelMonitor<Key, ChanSigner, T, F> {
275 let res = SimpleManyChannelMonitor {
276 monitors: Mutex::new(HashMap::new()),
280 fee_estimator: feeest,
286 /// Adds or updates the monitor which monitors the channel referred to by the given key.
287 pub fn add_monitor_by_key(&self, key: Key, monitor: ChannelMonitor<ChanSigner>) -> Result<(), MonitorUpdateError> {
288 let mut monitors = self.monitors.lock().unwrap();
289 let entry = match monitors.entry(key) {
290 hash_map::Entry::Occupied(_) => return Err(MonitorUpdateError("Channel monitor for given key is already present")),
291 hash_map::Entry::Vacant(e) => e,
293 match monitor.key_storage {
294 Storage::Local { ref funding_info, .. } => {
297 return Err(MonitorUpdateError("Try to update a useless monitor without funding_txo !"));
299 &Some((ref outpoint, ref script)) => {
300 log_trace!(self, "Got new Channel Monitor for channel {}", log_bytes!(outpoint.to_channel_id()[..]));
301 self.chain_monitor.install_watch_tx(&outpoint.txid, script);
302 self.chain_monitor.install_watch_outpoint((outpoint.txid, outpoint.index as u32), script);
306 Storage::Watchtower { .. } => {
307 self.chain_monitor.watch_all_txn();
310 for (txid, outputs) in monitor.get_outputs_to_watch().iter() {
311 for (idx, script) in outputs.iter().enumerate() {
312 self.chain_monitor.install_watch_outpoint((*txid, idx as u32), script);
315 entry.insert(monitor);
319 /// Updates the monitor which monitors the channel referred to by the given key.
320 pub fn update_monitor_by_key(&self, key: Key, update: ChannelMonitorUpdate) -> Result<(), MonitorUpdateError> {
321 let mut monitors = self.monitors.lock().unwrap();
322 match monitors.get_mut(&key) {
323 Some(orig_monitor) => {
324 log_trace!(self, "Updating Channel Monitor for channel {}", log_funding_info!(orig_monitor.key_storage));
325 orig_monitor.update_monitor(update, &self.broadcaster)
327 None => Err(MonitorUpdateError("No such monitor registered"))
332 impl<ChanSigner: ChannelKeys, T: Deref + Sync + Send, F: Deref + Sync + Send> ManyChannelMonitor<ChanSigner> for SimpleManyChannelMonitor<OutPoint, ChanSigner, T, F>
333 where T::Target: BroadcasterInterface,
334 F::Target: FeeEstimator
336 fn add_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor<ChanSigner>) -> Result<(), ChannelMonitorUpdateErr> {
337 match self.add_monitor_by_key(funding_txo, monitor) {
339 Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
343 fn update_monitor(&self, funding_txo: OutPoint, update: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr> {
344 match self.update_monitor_by_key(funding_txo, update) {
346 Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
350 fn get_and_clear_pending_htlcs_updated(&self) -> Vec<HTLCUpdate> {
351 let mut pending_htlcs_updated = Vec::new();
352 for chan in self.monitors.lock().unwrap().values_mut() {
353 pending_htlcs_updated.append(&mut chan.get_and_clear_pending_htlcs_updated());
355 pending_htlcs_updated
359 impl<Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys, T: Deref, F: Deref> events::EventsProvider for SimpleManyChannelMonitor<Key, ChanSigner, T, F>
360 where T::Target: BroadcasterInterface,
361 F::Target: FeeEstimator
363 fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
364 let mut pending_events = Vec::new();
365 for chan in self.monitors.lock().unwrap().values_mut() {
366 pending_events.append(&mut chan.get_and_clear_pending_events());
372 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
373 /// instead claiming it in its own individual transaction.
374 pub(crate) const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
375 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
376 /// HTLC-Success transaction.
377 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
378 /// transaction confirmed (and we use it in a few more, equivalent, places).
379 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 6;
380 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
381 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
382 /// copies of ChannelMonitors, including watchtowers). We could enforce the contract by failing
383 /// at CLTV expiration height but giving a grace period to our peer may be profitable for us if he
384 /// can provide an over-late preimage. Nevertheless, grace period has to be accounted in our
385 /// CLTV_EXPIRY_DELTA to be secure. Following this policy we may decrease the rate of channel failures
386 /// due to expiration but increase the cost of funds being locked longuer in case of failure.
387 /// This delay also cover a low-power peer being slow to process blocks and so being behind us on
388 /// accurate block height.
389 /// In case of onchain failure to be pass backward we may see the last block of ANTI_REORG_DELAY
390 /// with at worst this delay, so we are not only using this value as a mercy for them but also
391 /// us as a safeguard to delay with enough time.
392 pub(crate) const LATENCY_GRACE_PERIOD_BLOCKS: u32 = 3;
393 /// Number of blocks we wait on seeing a HTLC output being solved before we fail corresponding inbound
394 /// HTLCs. This prevents us from failing backwards and then getting a reorg resulting in us losing money.
395 /// We use also this delay to be sure we can remove our in-flight claim txn from bump candidates buffer.
396 /// It may cause spurrious generation of bumped claim txn but that's allright given the outpoint is already
397 /// solved by a previous claim tx. What we want to avoid is reorg evicting our claim tx and us not
398 /// keeping bumping another claim tx to solve the outpoint.
399 pub(crate) const ANTI_REORG_DELAY: u32 = 6;
401 enum Storage<ChanSigner: ChannelKeys> {
404 funding_key: SecretKey,
405 revocation_base_key: SecretKey,
406 htlc_base_key: SecretKey,
407 delayed_payment_base_key: SecretKey,
408 payment_base_key: SecretKey,
409 funding_info: Option<(OutPoint, Script)>,
410 current_remote_commitment_txid: Option<Sha256dHash>,
411 prev_remote_commitment_txid: Option<Sha256dHash>,
414 revocation_base_key: PublicKey,
415 htlc_base_key: PublicKey,
419 #[cfg(any(test, feature = "fuzztarget"))]
420 impl<ChanSigner: ChannelKeys> PartialEq for Storage<ChanSigner> {
421 fn eq(&self, other: &Self) -> bool {
423 Storage::Local { ref keys, .. } => {
426 Storage::Local { ref keys, .. } => keys.pubkeys() == k.pubkeys(),
427 Storage::Watchtower { .. } => false,
430 Storage::Watchtower {ref revocation_base_key, ref htlc_base_key} => {
431 let (rbk, hbk) = (revocation_base_key, htlc_base_key);
433 Storage::Local { .. } => false,
434 Storage::Watchtower {ref revocation_base_key, ref htlc_base_key} =>
435 revocation_base_key == rbk && htlc_base_key == hbk,
442 #[derive(Clone, PartialEq)]
443 struct LocalSignedTx {
444 /// txid of the transaction in tx, just used to make comparison faster
446 tx: LocalCommitmentTransaction,
447 revocation_key: PublicKey,
448 a_htlc_key: PublicKey,
449 b_htlc_key: PublicKey,
450 delayed_payment_key: PublicKey,
451 per_commitment_point: PublicKey,
453 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
456 /// When ChannelMonitor discovers an onchain outpoint being a step of a channel and that it needs
457 /// to generate a tx to push channel state forward, we cache outpoint-solving tx material to build
458 /// a new bumped one in case of lenghty confirmation delay
459 #[derive(Clone, PartialEq)]
460 pub(crate) enum InputMaterial {
462 witness_script: Script,
463 pubkey: Option<PublicKey>,
469 witness_script: Script,
471 preimage: Option<PaymentPreimage>,
476 witness_script: Script,
477 sigs: (Signature, Signature),
478 preimage: Option<PaymentPreimage>,
483 impl Writeable for InputMaterial {
484 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
486 &InputMaterial::Revoked { ref witness_script, ref pubkey, ref key, ref is_htlc, ref amount} => {
487 writer.write_all(&[0; 1])?;
488 witness_script.write(writer)?;
489 pubkey.write(writer)?;
490 writer.write_all(&key[..])?;
491 is_htlc.write(writer)?;
492 writer.write_all(&byte_utils::be64_to_array(*amount))?;
494 &InputMaterial::RemoteHTLC { ref witness_script, ref key, ref preimage, ref amount, ref locktime } => {
495 writer.write_all(&[1; 1])?;
496 witness_script.write(writer)?;
498 preimage.write(writer)?;
499 writer.write_all(&byte_utils::be64_to_array(*amount))?;
500 writer.write_all(&byte_utils::be32_to_array(*locktime))?;
502 &InputMaterial::LocalHTLC { ref witness_script, ref sigs, ref preimage, ref amount } => {
503 writer.write_all(&[2; 1])?;
504 witness_script.write(writer)?;
505 sigs.0.write(writer)?;
506 sigs.1.write(writer)?;
507 preimage.write(writer)?;
508 writer.write_all(&byte_utils::be64_to_array(*amount))?;
515 impl Readable for InputMaterial {
516 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
517 let input_material = match <u8 as Readable>::read(reader)? {
519 let witness_script = Readable::read(reader)?;
520 let pubkey = Readable::read(reader)?;
521 let key = Readable::read(reader)?;
522 let is_htlc = Readable::read(reader)?;
523 let amount = Readable::read(reader)?;
524 InputMaterial::Revoked {
533 let witness_script = Readable::read(reader)?;
534 let key = Readable::read(reader)?;
535 let preimage = Readable::read(reader)?;
536 let amount = Readable::read(reader)?;
537 let locktime = Readable::read(reader)?;
538 InputMaterial::RemoteHTLC {
547 let witness_script = Readable::read(reader)?;
548 let their_sig = Readable::read(reader)?;
549 let our_sig = Readable::read(reader)?;
550 let preimage = Readable::read(reader)?;
551 let amount = Readable::read(reader)?;
552 InputMaterial::LocalHTLC {
554 sigs: (their_sig, our_sig),
559 _ => return Err(DecodeError::InvalidValue),
565 /// ClaimRequest is a descriptor structure to communicate between detection
566 /// and reaction module. They are generated by ChannelMonitor while parsing
567 /// onchain txn leaked from a channel and handed over to OnchainTxHandler which
568 /// is responsible for opportunistic aggregation, selecting and enforcing
569 /// bumping logic, building and signing transactions.
570 pub(crate) struct ClaimRequest {
571 // Block height before which claiming is exclusive to one party,
572 // after reaching it, claiming may be contentious.
573 pub(crate) absolute_timelock: u32,
574 // Timeout tx must have nLocktime set which means aggregating multiple
575 // ones must take the higher nLocktime among them to satisfy all of them.
576 // Sadly it has few pitfalls, a) it takes longuer to get fund back b) CLTV_DELTA
577 // of a sooner-HTLC could be swallowed by the highest nLocktime of the HTLC set.
578 // Do simplify we mark them as non-aggregable.
579 pub(crate) aggregable: bool,
580 // Basic bitcoin outpoint (txid, vout)
581 pub(crate) outpoint: BitcoinOutPoint,
582 // Following outpoint type, set of data needed to generate transaction digest
583 // and satisfy witness program.
584 pub(crate) witness_data: InputMaterial
587 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
588 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
589 #[derive(Clone, PartialEq)]
591 /// HTLC output getting solved by a timeout, at maturation we pass upstream payment source information to solve
592 /// inbound HTLC in backward channel. Note, in case of preimage, we pass info to upstream without delay as we can
593 /// only win from it, so it's never an OnchainEvent
595 htlc_update: (HTLCSource, PaymentHash),
598 descriptor: SpendableOutputDescriptor,
602 const SERIALIZATION_VERSION: u8 = 1;
603 const MIN_SERIALIZATION_VERSION: u8 = 1;
605 #[cfg_attr(test, derive(PartialEq))]
607 pub(super) enum ChannelMonitorUpdateStep {
608 LatestLocalCommitmentTXInfo {
609 // TODO: We really need to not be generating a fully-signed transaction in Channel and
610 // passing it here, we need to hold off so that the ChanSigner can enforce a
611 // only-sign-local-state-for-broadcast once invariant:
612 commitment_tx: LocalCommitmentTransaction,
613 local_keys: chan_utils::TxCreationKeys,
615 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
617 LatestRemoteCommitmentTXInfo {
618 unsigned_commitment_tx: Transaction, // TODO: We should actually only need the txid here
619 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
620 commitment_number: u64,
621 their_revocation_point: PublicKey,
624 payment_preimage: PaymentPreimage,
630 /// Indicates our channel is likely a stale version, we're closing, but this update should
631 /// allow us to spend what is ours if our counterparty broadcasts their latest state.
632 RescueRemoteCommitmentTXInfo {
633 their_current_per_commitment_point: PublicKey,
635 /// Used to indicate that the no future updates will occur, and likely that the latest local
636 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
638 /// If set to false, we shouldn't broadcast the latest local commitment transaction as we
639 /// think we've fallen behind!
640 should_broadcast: bool,
644 impl Writeable for ChannelMonitorUpdateStep {
645 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
647 &ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { ref commitment_tx, ref local_keys, ref feerate_per_kw, ref htlc_outputs } => {
649 commitment_tx.write(w)?;
650 local_keys.write(w)?;
651 feerate_per_kw.write(w)?;
652 (htlc_outputs.len() as u64).write(w)?;
653 for &(ref output, ref signature, ref source) in htlc_outputs.iter() {
659 &ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { ref unsigned_commitment_tx, ref htlc_outputs, ref commitment_number, ref their_revocation_point } => {
661 unsigned_commitment_tx.write(w)?;
662 commitment_number.write(w)?;
663 their_revocation_point.write(w)?;
664 (htlc_outputs.len() as u64).write(w)?;
665 for &(ref output, ref source) in htlc_outputs.iter() {
667 source.as_ref().map(|b| b.as_ref()).write(w)?;
670 &ChannelMonitorUpdateStep::PaymentPreimage { ref payment_preimage } => {
672 payment_preimage.write(w)?;
674 &ChannelMonitorUpdateStep::CommitmentSecret { ref idx, ref secret } => {
679 &ChannelMonitorUpdateStep::RescueRemoteCommitmentTXInfo { ref their_current_per_commitment_point } => {
681 their_current_per_commitment_point.write(w)?;
683 &ChannelMonitorUpdateStep::ChannelForceClosed { ref should_broadcast } => {
685 should_broadcast.write(w)?;
691 impl Readable for ChannelMonitorUpdateStep {
692 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
693 match Readable::read(r)? {
695 Ok(ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo {
696 commitment_tx: Readable::read(r)?,
697 local_keys: Readable::read(r)?,
698 feerate_per_kw: Readable::read(r)?,
700 let len: u64 = Readable::read(r)?;
701 let mut res = Vec::new();
703 res.push((Readable::read(r)?, Readable::read(r)?, Readable::read(r)?));
710 Ok(ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo {
711 unsigned_commitment_tx: Readable::read(r)?,
712 commitment_number: Readable::read(r)?,
713 their_revocation_point: Readable::read(r)?,
715 let len: u64 = Readable::read(r)?;
716 let mut res = Vec::new();
718 res.push((Readable::read(r)?, <Option<HTLCSource> as Readable>::read(r)?.map(|o| Box::new(o))));
725 Ok(ChannelMonitorUpdateStep::PaymentPreimage {
726 payment_preimage: Readable::read(r)?,
730 Ok(ChannelMonitorUpdateStep::CommitmentSecret {
731 idx: Readable::read(r)?,
732 secret: Readable::read(r)?,
736 Ok(ChannelMonitorUpdateStep::RescueRemoteCommitmentTXInfo {
737 their_current_per_commitment_point: Readable::read(r)?,
741 Ok(ChannelMonitorUpdateStep::ChannelForceClosed {
742 should_broadcast: Readable::read(r)?
745 _ => Err(DecodeError::InvalidValue),
750 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
751 /// on-chain transactions to ensure no loss of funds occurs.
753 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
754 /// information and are actively monitoring the chain.
756 /// Pending Events or updated HTLCs which have not yet been read out by
757 /// get_and_clear_pending_htlcs_updated or get_and_clear_pending_events are serialized to disk and
758 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
759 /// gotten are fully handled before re-serializing the new state.
760 pub struct ChannelMonitor<ChanSigner: ChannelKeys> {
761 latest_update_id: u64,
762 commitment_transaction_number_obscure_factor: u64,
764 destination_script: Script,
765 broadcasted_local_revokable_script: Option<(Script, SecretKey, Script)>,
766 broadcasted_remote_payment_script: Option<(Script, SecretKey)>,
767 shutdown_script: Script,
769 key_storage: Storage<ChanSigner>,
770 their_htlc_base_key: Option<PublicKey>,
771 their_delayed_payment_base_key: Option<PublicKey>,
772 funding_redeemscript: Option<Script>,
773 channel_value_satoshis: Option<u64>,
774 // first is the idx of the first of the two revocation points
775 their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
777 our_to_self_delay: u16,
778 their_to_self_delay: Option<u16>,
780 commitment_secrets: CounterpartyCommitmentSecrets,
781 remote_claimable_outpoints: HashMap<Sha256dHash, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
782 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
783 /// Nor can we figure out their commitment numbers without the commitment transaction they are
784 /// spending. Thus, in order to claim them via revocation key, we track all the remote
785 /// commitment transactions which we find on-chain, mapping them to the commitment number which
786 /// can be used to derive the revocation key and claim the transactions.
787 remote_commitment_txn_on_chain: HashMap<Sha256dHash, (u64, Vec<Script>)>,
788 /// Cache used to make pruning of payment_preimages faster.
789 /// Maps payment_hash values to commitment numbers for remote transactions for non-revoked
790 /// remote transactions (ie should remain pretty small).
791 /// Serialized to disk but should generally not be sent to Watchtowers.
792 remote_hash_commitment_number: HashMap<PaymentHash, u64>,
794 // We store two local commitment transactions to avoid any race conditions where we may update
795 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
796 // various monitors for one channel being out of sync, and us broadcasting a local
797 // transaction for which we have deleted claim information on some watchtowers.
798 prev_local_signed_commitment_tx: Option<LocalSignedTx>,
799 current_local_signed_commitment_tx: Option<LocalSignedTx>,
801 // Used just for ChannelManager to make sure it has the latest channel data during
803 current_remote_commitment_number: u64,
805 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
807 pending_htlcs_updated: Vec<HTLCUpdate>,
808 pending_events: Vec<events::Event>,
810 // Used to track onchain events, i.e transactions parts of channels confirmed on chain, on which
811 // we have to take actions once they reach enough confs. Key is a block height timer, i.e we enforce
812 // actions when we receive a block with given height. Actions depend on OnchainEvent type.
813 onchain_events_waiting_threshold_conf: HashMap<u32, Vec<OnchainEvent>>,
815 // If we get serialized out and re-read, we need to make sure that the chain monitoring
816 // interface knows about the TXOs that we want to be notified of spends of. We could probably
817 // be smart and derive them from the above storage fields, but its much simpler and more
818 // Obviously Correct (tm) if we just keep track of them explicitly.
819 outputs_to_watch: HashMap<Sha256dHash, Vec<Script>>,
822 pub onchain_tx_handler: OnchainTxHandler,
824 onchain_tx_handler: OnchainTxHandler,
826 // We simply modify last_block_hash in Channel's block_connected so that serialization is
827 // consistent but hopefully the users' copy handles block_connected in a consistent way.
828 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
829 // their last_block_hash from its state and not based on updated copies that didn't run through
830 // the full block_connected).
831 pub(crate) last_block_hash: Sha256dHash,
832 secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
836 #[cfg(any(test, feature = "fuzztarget"))]
837 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
838 /// underlying object
839 impl<ChanSigner: ChannelKeys> PartialEq for ChannelMonitor<ChanSigner> {
840 fn eq(&self, other: &Self) -> bool {
841 if self.latest_update_id != other.latest_update_id ||
842 self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
843 self.destination_script != other.destination_script ||
844 self.broadcasted_local_revokable_script != other.broadcasted_local_revokable_script ||
845 self.broadcasted_remote_payment_script != other.broadcasted_remote_payment_script ||
846 self.key_storage != other.key_storage ||
847 self.their_htlc_base_key != other.their_htlc_base_key ||
848 self.their_delayed_payment_base_key != other.their_delayed_payment_base_key ||
849 self.funding_redeemscript != other.funding_redeemscript ||
850 self.channel_value_satoshis != other.channel_value_satoshis ||
851 self.their_cur_revocation_points != other.their_cur_revocation_points ||
852 self.our_to_self_delay != other.our_to_self_delay ||
853 self.their_to_self_delay != other.their_to_self_delay ||
854 self.commitment_secrets != other.commitment_secrets ||
855 self.remote_claimable_outpoints != other.remote_claimable_outpoints ||
856 self.remote_commitment_txn_on_chain != other.remote_commitment_txn_on_chain ||
857 self.remote_hash_commitment_number != other.remote_hash_commitment_number ||
858 self.prev_local_signed_commitment_tx != other.prev_local_signed_commitment_tx ||
859 self.current_remote_commitment_number != other.current_remote_commitment_number ||
860 self.current_local_signed_commitment_tx != other.current_local_signed_commitment_tx ||
861 self.payment_preimages != other.payment_preimages ||
862 self.pending_htlcs_updated != other.pending_htlcs_updated ||
863 self.pending_events.len() != other.pending_events.len() || // We trust events to round-trip properly
864 self.onchain_events_waiting_threshold_conf != other.onchain_events_waiting_threshold_conf ||
865 self.outputs_to_watch != other.outputs_to_watch
874 impl<ChanSigner: ChannelKeys + Writeable> ChannelMonitor<ChanSigner> {
875 /// Serializes into a vec, with various modes for the exposed pub fns
876 fn write<W: Writer>(&self, writer: &mut W, for_local_storage: bool) -> Result<(), ::std::io::Error> {
877 //TODO: We still write out all the serialization here manually instead of using the fancy
878 //serialization framework we have, we should migrate things over to it.
879 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
880 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
882 self.latest_update_id.write(writer)?;
884 // Set in initial Channel-object creation, so should always be set by now:
885 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
887 self.destination_script.write(writer)?;
888 if let Some(ref broadcasted_local_revokable_script) = self.broadcasted_local_revokable_script {
889 writer.write_all(&[0; 1])?;
890 broadcasted_local_revokable_script.0.write(writer)?;
891 broadcasted_local_revokable_script.1.write(writer)?;
892 broadcasted_local_revokable_script.2.write(writer)?;
894 writer.write_all(&[1; 1])?;
897 if let Some(ref broadcasted_remote_payment_script) = self.broadcasted_remote_payment_script {
898 writer.write_all(&[0; 1])?;
899 broadcasted_remote_payment_script.0.write(writer)?;
900 broadcasted_remote_payment_script.1.write(writer)?;
902 writer.write_all(&[1; 1])?;
904 self.shutdown_script.write(writer)?;
906 match self.key_storage {
907 Storage::Local { ref keys, ref funding_key, ref revocation_base_key, ref htlc_base_key, ref delayed_payment_base_key, ref payment_base_key, ref funding_info, ref current_remote_commitment_txid, ref prev_remote_commitment_txid } => {
908 writer.write_all(&[0; 1])?;
910 writer.write_all(&funding_key[..])?;
911 writer.write_all(&revocation_base_key[..])?;
912 writer.write_all(&htlc_base_key[..])?;
913 writer.write_all(&delayed_payment_base_key[..])?;
914 writer.write_all(&payment_base_key[..])?;
916 &Some((ref outpoint, ref script)) => {
917 writer.write_all(&outpoint.txid[..])?;
918 writer.write_all(&byte_utils::be16_to_array(outpoint.index))?;
919 script.write(writer)?;
922 debug_assert!(false, "Try to serialize a useless Local monitor !");
925 current_remote_commitment_txid.write(writer)?;
926 prev_remote_commitment_txid.write(writer)?;
928 Storage::Watchtower { .. } => unimplemented!(),
931 writer.write_all(&self.their_htlc_base_key.as_ref().unwrap().serialize())?;
932 writer.write_all(&self.their_delayed_payment_base_key.as_ref().unwrap().serialize())?;
933 self.funding_redeemscript.as_ref().unwrap().write(writer)?;
934 self.channel_value_satoshis.unwrap().write(writer)?;
936 match self.their_cur_revocation_points {
937 Some((idx, pubkey, second_option)) => {
938 writer.write_all(&byte_utils::be48_to_array(idx))?;
939 writer.write_all(&pubkey.serialize())?;
940 match second_option {
941 Some(second_pubkey) => {
942 writer.write_all(&second_pubkey.serialize())?;
945 writer.write_all(&[0; 33])?;
950 writer.write_all(&byte_utils::be48_to_array(0))?;
954 writer.write_all(&byte_utils::be16_to_array(self.our_to_self_delay))?;
955 writer.write_all(&byte_utils::be16_to_array(self.their_to_self_delay.unwrap()))?;
957 self.commitment_secrets.write(writer)?;
959 macro_rules! serialize_htlc_in_commitment {
960 ($htlc_output: expr) => {
961 writer.write_all(&[$htlc_output.offered as u8; 1])?;
962 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
963 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
964 writer.write_all(&$htlc_output.payment_hash.0[..])?;
965 $htlc_output.transaction_output_index.write(writer)?;
969 writer.write_all(&byte_utils::be64_to_array(self.remote_claimable_outpoints.len() as u64))?;
970 for (ref txid, ref htlc_infos) in self.remote_claimable_outpoints.iter() {
971 writer.write_all(&txid[..])?;
972 writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
973 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
974 serialize_htlc_in_commitment!(htlc_output);
975 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
979 writer.write_all(&byte_utils::be64_to_array(self.remote_commitment_txn_on_chain.len() as u64))?;
980 for (ref txid, &(commitment_number, ref txouts)) in self.remote_commitment_txn_on_chain.iter() {
981 writer.write_all(&txid[..])?;
982 writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
983 (txouts.len() as u64).write(writer)?;
984 for script in txouts.iter() {
985 script.write(writer)?;
989 if for_local_storage {
990 writer.write_all(&byte_utils::be64_to_array(self.remote_hash_commitment_number.len() as u64))?;
991 for (ref payment_hash, commitment_number) in self.remote_hash_commitment_number.iter() {
992 writer.write_all(&payment_hash.0[..])?;
993 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
996 writer.write_all(&byte_utils::be64_to_array(0))?;
999 macro_rules! serialize_local_tx {
1000 ($local_tx: expr) => {
1001 $local_tx.tx.write(writer)?;
1002 writer.write_all(&$local_tx.revocation_key.serialize())?;
1003 writer.write_all(&$local_tx.a_htlc_key.serialize())?;
1004 writer.write_all(&$local_tx.b_htlc_key.serialize())?;
1005 writer.write_all(&$local_tx.delayed_payment_key.serialize())?;
1006 writer.write_all(&$local_tx.per_commitment_point.serialize())?;
1008 writer.write_all(&byte_utils::be64_to_array($local_tx.feerate_per_kw))?;
1009 writer.write_all(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64))?;
1010 for &(ref htlc_output, ref sig, ref htlc_source) in $local_tx.htlc_outputs.iter() {
1011 serialize_htlc_in_commitment!(htlc_output);
1012 if let &Some(ref their_sig) = sig {
1014 writer.write_all(&their_sig.serialize_compact())?;
1018 htlc_source.write(writer)?;
1023 if let Some(ref prev_local_tx) = self.prev_local_signed_commitment_tx {
1024 writer.write_all(&[1; 1])?;
1025 serialize_local_tx!(prev_local_tx);
1027 writer.write_all(&[0; 1])?;
1030 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
1031 writer.write_all(&[1; 1])?;
1032 serialize_local_tx!(cur_local_tx);
1034 writer.write_all(&[0; 1])?;
1037 if for_local_storage {
1038 writer.write_all(&byte_utils::be48_to_array(self.current_remote_commitment_number))?;
1040 writer.write_all(&byte_utils::be48_to_array(0))?;
1043 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
1044 for payment_preimage in self.payment_preimages.values() {
1045 writer.write_all(&payment_preimage.0[..])?;
1048 writer.write_all(&byte_utils::be64_to_array(self.pending_htlcs_updated.len() as u64))?;
1049 for data in self.pending_htlcs_updated.iter() {
1050 data.write(writer)?;
1053 writer.write_all(&byte_utils::be64_to_array(self.pending_events.len() as u64))?;
1054 for event in self.pending_events.iter() {
1055 event.write(writer)?;
1058 self.last_block_hash.write(writer)?;
1060 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_waiting_threshold_conf.len() as u64))?;
1061 for (ref target, ref events) in self.onchain_events_waiting_threshold_conf.iter() {
1062 writer.write_all(&byte_utils::be32_to_array(**target))?;
1063 writer.write_all(&byte_utils::be64_to_array(events.len() as u64))?;
1064 for ev in events.iter() {
1066 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1068 htlc_update.0.write(writer)?;
1069 htlc_update.1.write(writer)?;
1071 OnchainEvent::MaturingOutput { ref descriptor } => {
1073 descriptor.write(writer)?;
1079 (self.outputs_to_watch.len() as u64).write(writer)?;
1080 for (txid, output_scripts) in self.outputs_to_watch.iter() {
1081 txid.write(writer)?;
1082 (output_scripts.len() as u64).write(writer)?;
1083 for script in output_scripts.iter() {
1084 script.write(writer)?;
1087 self.onchain_tx_handler.write(writer)?;
1092 /// Writes this monitor into the given writer, suitable for writing to disk.
1094 /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
1095 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
1096 /// the "reorg path" (ie not just starting at the same height but starting at the highest
1097 /// common block that appears on your best chain as well as on the chain which contains the
1098 /// last block hash returned) upon deserializing the object!
1099 pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
1100 self.write(writer, true)
1103 /// Encodes this monitor into the given writer, suitable for sending to a remote watchtower
1105 /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
1106 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
1107 /// the "reorg path" (ie not just starting at the same height but starting at the highest
1108 /// common block that appears on your best chain as well as on the chain which contains the
1109 /// last block hash returned) upon deserializing the object!
1110 pub fn write_for_watchtower<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
1111 self.write(writer, false)
1115 impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
1116 pub(super) fn new(keys: ChanSigner, shutdown_pubkey: &PublicKey,
1117 our_to_self_delay: u16, destination_script: &Script, funding_info: (OutPoint, Script),
1118 their_htlc_base_key: &PublicKey, their_delayed_payment_base_key: &PublicKey,
1119 their_to_self_delay: u16, funding_redeemscript: Script, channel_value_satoshis: u64,
1120 commitment_transaction_number_obscure_factor: u64,
1121 logger: Arc<Logger>) -> ChannelMonitor<ChanSigner> {
1123 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
1124 let funding_key = keys.funding_key().clone();
1125 let revocation_base_key = keys.revocation_base_key().clone();
1126 let htlc_base_key = keys.htlc_base_key().clone();
1127 let delayed_payment_base_key = keys.delayed_payment_base_key().clone();
1128 let payment_base_key = keys.payment_base_key().clone();
1129 let our_channel_close_key_hash = Hash160::hash(&shutdown_pubkey.serialize());
1130 let shutdown_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
1132 latest_update_id: 0,
1133 commitment_transaction_number_obscure_factor,
1135 destination_script: destination_script.clone(),
1136 broadcasted_local_revokable_script: None,
1137 broadcasted_remote_payment_script: None,
1140 key_storage: Storage::Local {
1143 revocation_base_key,
1145 delayed_payment_base_key,
1147 funding_info: Some(funding_info),
1148 current_remote_commitment_txid: None,
1149 prev_remote_commitment_txid: None,
1151 their_htlc_base_key: Some(their_htlc_base_key.clone()),
1152 their_delayed_payment_base_key: Some(their_delayed_payment_base_key.clone()),
1153 funding_redeemscript: Some(funding_redeemscript),
1154 channel_value_satoshis: Some(channel_value_satoshis),
1155 their_cur_revocation_points: None,
1157 our_to_self_delay: our_to_self_delay,
1158 their_to_self_delay: Some(their_to_self_delay),
1160 commitment_secrets: CounterpartyCommitmentSecrets::new(),
1161 remote_claimable_outpoints: HashMap::new(),
1162 remote_commitment_txn_on_chain: HashMap::new(),
1163 remote_hash_commitment_number: HashMap::new(),
1165 prev_local_signed_commitment_tx: None,
1166 current_local_signed_commitment_tx: None,
1167 current_remote_commitment_number: 1 << 48,
1169 payment_preimages: HashMap::new(),
1170 pending_htlcs_updated: Vec::new(),
1171 pending_events: Vec::new(),
1173 onchain_events_waiting_threshold_conf: HashMap::new(),
1174 outputs_to_watch: HashMap::new(),
1176 onchain_tx_handler: OnchainTxHandler::new(destination_script.clone(), logger.clone()),
1178 last_block_hash: Default::default(),
1179 secp_ctx: Secp256k1::new(),
1184 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
1185 /// needed by local commitment transactions HTCLs nor by remote ones. Unless we haven't already seen remote
1186 /// commitment transaction's secret, they are de facto pruned (we can use revocation key).
1187 pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
1188 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
1189 return Err(MonitorUpdateError("Previous secret did not match new one"));
1192 // Prune HTLCs from the previous remote commitment tx so we don't generate failure/fulfill
1193 // events for now-revoked/fulfilled HTLCs.
1194 if let Storage::Local { ref mut prev_remote_commitment_txid, .. } = self.key_storage {
1195 if let Some(txid) = prev_remote_commitment_txid.take() {
1196 for &mut (_, ref mut source) in self.remote_claimable_outpoints.get_mut(&txid).unwrap() {
1202 if !self.payment_preimages.is_empty() {
1203 let local_signed_commitment_tx = self.current_local_signed_commitment_tx.as_ref().expect("Channel needs at least an initial commitment tx !");
1204 let prev_local_signed_commitment_tx = self.prev_local_signed_commitment_tx.as_ref();
1205 let min_idx = self.get_min_seen_secret();
1206 let remote_hash_commitment_number = &mut self.remote_hash_commitment_number;
1208 self.payment_preimages.retain(|&k, _| {
1209 for &(ref htlc, _, _) in &local_signed_commitment_tx.htlc_outputs {
1210 if k == htlc.payment_hash {
1214 if let Some(prev_local_commitment_tx) = prev_local_signed_commitment_tx {
1215 for &(ref htlc, _, _) in prev_local_commitment_tx.htlc_outputs.iter() {
1216 if k == htlc.payment_hash {
1221 let contains = if let Some(cn) = remote_hash_commitment_number.get(&k) {
1228 remote_hash_commitment_number.remove(&k);
1237 /// Informs this monitor of the latest remote (ie non-broadcastable) commitment transaction.
1238 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
1239 /// possibly future revocation/preimage information) to claim outputs where possible.
1240 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
1241 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) {
1242 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
1243 // so that a remote monitor doesn't learn anything unless there is a malicious close.
1244 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
1246 for &(ref htlc, _) in &htlc_outputs {
1247 self.remote_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
1250 let new_txid = unsigned_commitment_tx.txid();
1251 log_trace!(self, "Tracking new remote commitment transaction with txid {} at commitment number {} with {} HTLC outputs", new_txid, commitment_number, htlc_outputs.len());
1252 log_trace!(self, "New potential remote commitment transaction: {}", encode::serialize_hex(unsigned_commitment_tx));
1253 if let Storage::Local { ref mut current_remote_commitment_txid, ref mut prev_remote_commitment_txid, .. } = self.key_storage {
1254 *prev_remote_commitment_txid = current_remote_commitment_txid.take();
1255 *current_remote_commitment_txid = Some(new_txid);
1257 self.remote_claimable_outpoints.insert(new_txid, htlc_outputs);
1258 self.current_remote_commitment_number = commitment_number;
1259 //TODO: Merge this into the other per-remote-transaction output storage stuff
1260 match self.their_cur_revocation_points {
1261 Some(old_points) => {
1262 if old_points.0 == commitment_number + 1 {
1263 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
1264 } else if old_points.0 == commitment_number + 2 {
1265 if let Some(old_second_point) = old_points.2 {
1266 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
1268 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1271 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1275 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1280 pub(super) fn provide_rescue_remote_commitment_tx_info(&mut self, their_revocation_point: PublicKey) {
1281 match self.key_storage {
1282 Storage::Local { ref payment_base_key, ref keys, .. } => {
1283 if let Ok(payment_key) = chan_utils::derive_public_key(&self.secp_ctx, &their_revocation_point, &keys.pubkeys().payment_basepoint) {
1284 let to_remote_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0)
1285 .push_slice(&Hash160::hash(&payment_key.serialize())[..])
1287 if let Ok(to_remote_key) = chan_utils::derive_private_key(&self.secp_ctx, &their_revocation_point, &payment_base_key) {
1288 self.broadcasted_remote_payment_script = Some((to_remote_script, to_remote_key));
1292 Storage::Watchtower { .. } => {}
1296 /// Informs this monitor of the latest local (ie broadcastable) commitment transaction. The
1297 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
1298 /// is important that any clones of this channel monitor (including remote clones) by kept
1299 /// up-to-date as our local commitment transaction is updated.
1300 /// Panics if set_their_to_self_delay has never been called.
1301 pub(super) fn provide_latest_local_commitment_tx_info(&mut self, commitment_tx: LocalCommitmentTransaction, local_keys: chan_utils::TxCreationKeys, feerate_per_kw: u64, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), MonitorUpdateError> {
1302 if self.their_to_self_delay.is_none() {
1303 return Err(MonitorUpdateError("Got a local commitment tx info update before we'd set basic information about the channel"));
1305 self.prev_local_signed_commitment_tx = self.current_local_signed_commitment_tx.take();
1306 self.current_local_signed_commitment_tx = Some(LocalSignedTx {
1307 txid: commitment_tx.txid(),
1309 revocation_key: local_keys.revocation_key,
1310 a_htlc_key: local_keys.a_htlc_key,
1311 b_htlc_key: local_keys.b_htlc_key,
1312 delayed_payment_key: local_keys.a_delayed_payment_key,
1313 per_commitment_point: local_keys.per_commitment_point,
1320 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
1321 /// commitment_tx_infos which contain the payment hash have been revoked.
1322 pub(super) fn provide_payment_preimage(&mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage) {
1323 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
1326 pub(super) fn broadcast_latest_local_commitment_txn<B: Deref>(&mut self, broadcaster: &B)
1327 where B::Target: BroadcasterInterface,
1329 for tx in self.get_latest_local_commitment_txn().iter() {
1330 broadcaster.broadcast_transaction(tx);
1334 /// Used in Channel to cheat wrt the update_ids since it plays games, will be removed soon!
1335 pub(super) fn update_monitor_ooo(&mut self, mut updates: ChannelMonitorUpdate) -> Result<(), MonitorUpdateError> {
1336 for update in updates.updates.drain(..) {
1338 ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { commitment_tx, local_keys, feerate_per_kw, htlc_outputs } =>
1339 self.provide_latest_local_commitment_tx_info(commitment_tx, local_keys, feerate_per_kw, htlc_outputs)?,
1340 ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
1341 self.provide_latest_remote_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point),
1342 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
1343 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
1344 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
1345 self.provide_secret(idx, secret)?,
1346 ChannelMonitorUpdateStep::RescueRemoteCommitmentTXInfo { their_current_per_commitment_point } =>
1347 self.provide_rescue_remote_commitment_tx_info(their_current_per_commitment_point),
1348 ChannelMonitorUpdateStep::ChannelForceClosed { .. } => {},
1351 self.latest_update_id = updates.update_id;
1355 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
1358 /// panics if the given update is not the next update by update_id.
1359 pub fn update_monitor<B: Deref>(&mut self, mut updates: ChannelMonitorUpdate, broadcaster: &B) -> Result<(), MonitorUpdateError>
1360 where B::Target: BroadcasterInterface,
1362 if self.latest_update_id + 1 != updates.update_id {
1363 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
1365 for update in updates.updates.drain(..) {
1367 ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { commitment_tx, local_keys, feerate_per_kw, htlc_outputs } =>
1368 self.provide_latest_local_commitment_tx_info(commitment_tx, local_keys, feerate_per_kw, htlc_outputs)?,
1369 ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
1370 self.provide_latest_remote_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point),
1371 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
1372 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
1373 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
1374 self.provide_secret(idx, secret)?,
1375 ChannelMonitorUpdateStep::RescueRemoteCommitmentTXInfo { their_current_per_commitment_point } =>
1376 self.provide_rescue_remote_commitment_tx_info(their_current_per_commitment_point),
1377 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
1378 if should_broadcast {
1379 self.broadcast_latest_local_commitment_txn(broadcaster);
1381 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");
1386 self.latest_update_id = updates.update_id;
1390 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
1392 pub fn get_latest_update_id(&self) -> u64 {
1393 self.latest_update_id
1396 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
1397 pub fn get_funding_txo(&self) -> Option<OutPoint> {
1398 match self.key_storage {
1399 Storage::Local { ref funding_info, .. } => {
1400 match funding_info {
1401 &Some((outpoint, _)) => Some(outpoint),
1405 Storage::Watchtower { .. } => {
1411 /// Gets a list of txids, with their output scripts (in the order they appear in the
1412 /// transaction), which we must learn about spends of via block_connected().
1413 pub fn get_outputs_to_watch(&self) -> &HashMap<Sha256dHash, Vec<Script>> {
1414 &self.outputs_to_watch
1417 /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
1418 /// Generally useful when deserializing as during normal operation the return values of
1419 /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
1420 /// that the get_funding_txo outpoint and transaction must also be monitored for!).
1421 pub fn get_monitored_outpoints(&self) -> Vec<(Sha256dHash, u32, &Script)> {
1422 let mut res = Vec::with_capacity(self.remote_commitment_txn_on_chain.len() * 2);
1423 for (ref txid, &(_, ref outputs)) in self.remote_commitment_txn_on_chain.iter() {
1424 for (idx, output) in outputs.iter().enumerate() {
1425 res.push(((*txid).clone(), idx as u32, output));
1431 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1432 /// ChannelManager via ManyChannelMonitor::get_and_clear_pending_htlcs_updated().
1433 pub fn get_and_clear_pending_htlcs_updated(&mut self) -> Vec<HTLCUpdate> {
1434 let mut ret = Vec::new();
1435 mem::swap(&mut ret, &mut self.pending_htlcs_updated);
1439 /// Gets the list of pending events which were generated by previous actions, clearing the list
1442 /// This is called by ManyChannelMonitor::get_and_clear_pending_events() and is equivalent to
1443 /// EventsProvider::get_and_clear_pending_events() except that it requires &mut self as we do
1444 /// no internal locking in ChannelMonitors.
1445 pub fn get_and_clear_pending_events(&mut self) -> Vec<events::Event> {
1446 let mut ret = Vec::new();
1447 mem::swap(&mut ret, &mut self.pending_events);
1451 /// Can only fail if idx is < get_min_seen_secret
1452 pub(super) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
1453 self.commitment_secrets.get_secret(idx)
1456 pub(super) fn get_min_seen_secret(&self) -> u64 {
1457 self.commitment_secrets.get_min_seen_secret()
1460 pub(super) fn get_cur_remote_commitment_number(&self) -> u64 {
1461 self.current_remote_commitment_number
1464 pub(super) fn get_cur_local_commitment_number(&self) -> u64 {
1465 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1466 0xffff_ffff_ffff - ((((local_tx.tx.without_valid_witness().input[0].sequence as u64 & 0xffffff) << 3*8) | (local_tx.tx.without_valid_witness().lock_time as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor)
1467 } else { 0xffff_ffff_ffff }
1470 /// Attempts to claim a remote commitment transaction's outputs using the revocation key and
1471 /// data in remote_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
1472 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
1473 /// HTLC-Success/HTLC-Timeout transactions.
1474 /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
1475 /// revoked remote commitment tx
1476 fn check_spend_remote_transaction(&mut self, tx: &Transaction, height: u32) -> (Vec<ClaimRequest>, (Sha256dHash, Vec<TxOut>)) {
1477 // Most secp and related errors trying to create keys means we have no hope of constructing
1478 // a spend transaction...so we return no transactions to broadcast
1479 let mut claimable_outpoints = Vec::new();
1480 let mut watch_outputs = Vec::new();
1482 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1483 let per_commitment_option = self.remote_claimable_outpoints.get(&commitment_txid);
1485 macro_rules! ignore_error {
1486 ( $thing : expr ) => {
1489 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs))
1494 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);
1495 if commitment_number >= self.get_min_seen_secret() {
1496 let secret = self.get_secret(commitment_number).unwrap();
1497 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1498 let (revocation_pubkey, revocation_key, b_htlc_key, local_payment_key) = match self.key_storage {
1499 Storage::Local { ref keys, ref revocation_base_key, ref payment_base_key, .. } => {
1500 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1501 (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &keys.pubkeys().revocation_basepoint)),
1502 ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &revocation_base_key)),
1503 ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &keys.pubkeys().htlc_basepoint)),
1504 ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, &per_commitment_point, &payment_base_key)))
1506 Storage::Watchtower { .. } => {
1510 let delayed_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key), &self.their_delayed_payment_base_key.unwrap()));
1511 let a_htlc_key = match self.their_htlc_base_key {
1512 None => return (claimable_outpoints, (commitment_txid, watch_outputs)),
1513 Some(their_htlc_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key), &their_htlc_base_key)),
1516 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.our_to_self_delay, &delayed_key);
1517 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1519 self.broadcasted_remote_payment_script = {
1520 // Note that the Network here is ignored as we immediately drop the address for the
1521 // script_pubkey version
1522 let payment_hash160 = Hash160::hash(&PublicKey::from_secret_key(&self.secp_ctx, &local_payment_key).serialize());
1523 Some((Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_hash160[..]).into_script(), local_payment_key))
1526 // First, process non-htlc outputs (to_local & to_remote)
1527 for (idx, outp) in tx.output.iter().enumerate() {
1528 if outp.script_pubkey == revokeable_p2wsh {
1529 let witness_data = InputMaterial::Revoked { witness_script: revokeable_redeemscript.clone(), pubkey: Some(revocation_pubkey), key: revocation_key, is_htlc: false, amount: outp.value };
1530 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});
1534 // Then, try to find revoked htlc outputs
1535 if let Some(ref per_commitment_data) = per_commitment_option {
1536 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1537 if let Some(transaction_output_index) = htlc.transaction_output_index {
1538 let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1539 if transaction_output_index as usize >= tx.output.len() ||
1540 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
1541 tx.output[transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
1542 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1544 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 };
1545 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable: true, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1550 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
1551 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
1552 // We're definitely a remote commitment transaction!
1553 log_trace!(self, "Got broadcast of revoked remote commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
1554 watch_outputs.append(&mut tx.output.clone());
1555 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1557 macro_rules! check_htlc_fails {
1558 ($txid: expr, $commitment_tx: expr) => {
1559 if let Some(ref outpoints) = self.remote_claimable_outpoints.get($txid) {
1560 for &(ref htlc, ref source_option) in outpoints.iter() {
1561 if let &Some(ref source) = source_option {
1562 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);
1563 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1564 hash_map::Entry::Occupied(mut entry) => {
1565 let e = entry.get_mut();
1566 e.retain(|ref event| {
1568 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1569 return htlc_update.0 != **source
1574 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1576 hash_map::Entry::Vacant(entry) => {
1577 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1585 if let Storage::Local { ref current_remote_commitment_txid, ref prev_remote_commitment_txid, .. } = self.key_storage {
1586 if let &Some(ref txid) = current_remote_commitment_txid {
1587 check_htlc_fails!(txid, "current");
1589 if let &Some(ref txid) = prev_remote_commitment_txid {
1590 check_htlc_fails!(txid, "remote");
1593 // No need to check local commitment txn, symmetric HTLCSource must be present as per-htlc data on remote commitment tx
1595 } else if let Some(per_commitment_data) = per_commitment_option {
1596 // While this isn't useful yet, there is a potential race where if a counterparty
1597 // revokes a state at the same time as the commitment transaction for that state is
1598 // confirmed, and the watchtower receives the block before the user, the user could
1599 // upload a new ChannelMonitor with the revocation secret but the watchtower has
1600 // already processed the block, resulting in the remote_commitment_txn_on_chain entry
1601 // not being generated by the above conditional. Thus, to be safe, we go ahead and
1603 watch_outputs.append(&mut tx.output.clone());
1604 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1606 log_trace!(self, "Got broadcast of non-revoked remote commitment transaction {}", commitment_txid);
1608 macro_rules! check_htlc_fails {
1609 ($txid: expr, $commitment_tx: expr, $id: tt) => {
1610 if let Some(ref latest_outpoints) = self.remote_claimable_outpoints.get($txid) {
1611 $id: for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1612 if let &Some(ref source) = source_option {
1613 // Check if the HTLC is present in the commitment transaction that was
1614 // broadcast, but not if it was below the dust limit, which we should
1615 // fail backwards immediately as there is no way for us to learn the
1616 // payment_preimage.
1617 // Note that if the dust limit were allowed to change between
1618 // commitment transactions we'd want to be check whether *any*
1619 // broadcastable commitment transaction has the HTLC in it, but it
1620 // cannot currently change after channel initialization, so we don't
1622 for &(ref broadcast_htlc, ref broadcast_source) in per_commitment_data.iter() {
1623 if broadcast_htlc.transaction_output_index.is_some() && Some(source) == broadcast_source.as_ref() {
1627 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);
1628 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1629 hash_map::Entry::Occupied(mut entry) => {
1630 let e = entry.get_mut();
1631 e.retain(|ref event| {
1633 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1634 return htlc_update.0 != **source
1639 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1641 hash_map::Entry::Vacant(entry) => {
1642 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1650 if let Storage::Local { ref current_remote_commitment_txid, ref prev_remote_commitment_txid, .. } = self.key_storage {
1651 if let &Some(ref txid) = current_remote_commitment_txid {
1652 check_htlc_fails!(txid, "current", 'current_loop);
1654 if let &Some(ref txid) = prev_remote_commitment_txid {
1655 check_htlc_fails!(txid, "previous", 'prev_loop);
1659 if let Some(revocation_points) = self.their_cur_revocation_points {
1660 let revocation_point_option =
1661 if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1662 else if let Some(point) = revocation_points.2.as_ref() {
1663 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1665 if let Some(revocation_point) = revocation_point_option {
1666 let (revocation_pubkey, b_htlc_key, htlc_privkey, local_payment_key) = match self.key_storage {
1667 Storage::Local { ref keys, ref htlc_base_key, ref payment_base_key, .. } => {
1668 (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &keys.pubkeys().revocation_basepoint)),
1669 ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &keys.pubkeys().htlc_basepoint)),
1670 ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, revocation_point, &htlc_base_key)),
1671 ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, revocation_point, &payment_base_key)))
1673 Storage::Watchtower { .. } => { unimplemented!() }
1675 let a_htlc_key = match self.their_htlc_base_key {
1676 None => return (claimable_outpoints, (commitment_txid, watch_outputs)),
1677 Some(their_htlc_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &their_htlc_base_key)),
1680 self.broadcasted_remote_payment_script = {
1681 // Note that the Network here is ignored as we immediately drop the address for the
1682 // script_pubkey version
1683 let payment_hash160 = Hash160::hash(&PublicKey::from_secret_key(&self.secp_ctx, &local_payment_key).serialize());
1684 Some((Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_hash160[..]).into_script(), local_payment_key))
1687 // Then, try to find htlc outputs
1688 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1689 if let Some(transaction_output_index) = htlc.transaction_output_index {
1690 let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1691 if transaction_output_index as usize >= tx.output.len() ||
1692 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
1693 tx.output[transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
1694 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1696 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
1697 let aggregable = if !htlc.offered { false } else { true };
1698 if preimage.is_some() || !htlc.offered {
1699 let witness_data = InputMaterial::RemoteHTLC { witness_script: expected_script, key: htlc_privkey, preimage, amount: htlc.amount_msat / 1000, locktime: htlc.cltv_expiry };
1700 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1707 (claimable_outpoints, (commitment_txid, watch_outputs))
1710 /// Attempts to claim a remote HTLC-Success/HTLC-Timeout's outputs using the revocation key
1711 fn check_spend_remote_htlc(&mut self, tx: &Transaction, commitment_number: u64, height: u32) -> (Vec<ClaimRequest>, Option<(Sha256dHash, Vec<TxOut>)>) {
1712 let htlc_txid = tx.txid();
1713 if tx.input.len() != 1 || tx.output.len() != 1 || tx.input[0].witness.len() != 5 {
1714 return (Vec::new(), None)
1717 macro_rules! ignore_error {
1718 ( $thing : expr ) => {
1721 Err(_) => return (Vec::new(), None)
1726 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
1727 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1728 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1729 let (revocation_pubkey, revocation_key) = match self.key_storage {
1730 Storage::Local { ref keys, ref revocation_base_key, .. } => {
1731 (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &keys.pubkeys().revocation_basepoint)),
1732 ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, revocation_base_key)))
1734 Storage::Watchtower { .. } => { unimplemented!() }
1736 let delayed_key = match self.their_delayed_payment_base_key {
1737 None => return (Vec::new(), None),
1738 Some(their_delayed_payment_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &their_delayed_payment_base_key)),
1740 let redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.our_to_self_delay, &delayed_key);
1742 log_trace!(self, "Remote HTLC broadcast {}:{}", htlc_txid, 0);
1743 let witness_data = InputMaterial::Revoked { witness_script: redeemscript, pubkey: Some(revocation_pubkey), key: revocation_key, is_htlc: false, amount: tx.output[0].value };
1744 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 });
1745 (claimable_outpoints, Some((htlc_txid, tx.output.clone())))
1748 fn broadcast_by_local_state(&self, local_tx: &LocalSignedTx, delayed_payment_base_key: &SecretKey) -> (Vec<Transaction>, Vec<TxOut>, Option<(Script, SecretKey, Script)>) {
1749 let mut res = Vec::with_capacity(local_tx.htlc_outputs.len());
1750 let mut watch_outputs = Vec::with_capacity(local_tx.htlc_outputs.len());
1752 let redeemscript = chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.their_to_self_delay.unwrap(), &local_tx.delayed_payment_key);
1753 let broadcasted_local_revokable_script = if let Ok(local_delayedkey) = chan_utils::derive_private_key(&self.secp_ctx, &local_tx.per_commitment_point, delayed_payment_base_key) {
1754 Some((redeemscript.to_v0_p2wsh(), local_delayedkey, redeemscript))
1757 if let &Storage::Local { ref htlc_base_key, .. } = &self.key_storage {
1758 for &(ref htlc, ref sigs, _) in local_tx.htlc_outputs.iter() {
1759 if let Some(transaction_output_index) = htlc.transaction_output_index {
1760 if let &Some(ref their_sig) = sigs {
1762 log_trace!(self, "Broadcasting HTLC-Timeout transaction against local commitment transactions");
1763 let mut htlc_timeout_tx = chan_utils::build_htlc_transaction(&local_tx.txid, local_tx.feerate_per_kw, self.their_to_self_delay.unwrap(), htlc, &local_tx.delayed_payment_key, &local_tx.revocation_key);
1764 let (our_sig, htlc_script) = match
1765 chan_utils::sign_htlc_transaction(&mut htlc_timeout_tx, their_sig, &None, htlc, &local_tx.a_htlc_key, &local_tx.b_htlc_key, &local_tx.revocation_key, &local_tx.per_commitment_point, htlc_base_key, &self.secp_ctx) {
1770 let mut per_input_material = HashMap::with_capacity(1);
1771 per_input_material.insert(htlc_timeout_tx.input[0].previous_output, InputMaterial::LocalHTLC { witness_script: htlc_script, sigs: (*their_sig, our_sig), preimage: None, amount: htlc.amount_msat / 1000});
1772 //TODO: with option_simplified_commitment track outpoint too
1773 log_trace!(self, "Outpoint {}:{} is being being claimed", htlc_timeout_tx.input[0].previous_output.vout, htlc_timeout_tx.input[0].previous_output.txid);
1774 res.push(htlc_timeout_tx);
1776 if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1777 log_trace!(self, "Broadcasting HTLC-Success transaction against local commitment transactions");
1778 let mut htlc_success_tx = chan_utils::build_htlc_transaction(&local_tx.txid, local_tx.feerate_per_kw, self.their_to_self_delay.unwrap(), htlc, &local_tx.delayed_payment_key, &local_tx.revocation_key);
1779 let (our_sig, htlc_script) = match
1780 chan_utils::sign_htlc_transaction(&mut htlc_success_tx, their_sig, &Some(*payment_preimage), htlc, &local_tx.a_htlc_key, &local_tx.b_htlc_key, &local_tx.revocation_key, &local_tx.per_commitment_point, htlc_base_key, &self.secp_ctx) {
1785 let mut per_input_material = HashMap::with_capacity(1);
1786 per_input_material.insert(htlc_success_tx.input[0].previous_output, InputMaterial::LocalHTLC { witness_script: htlc_script, sigs: (*their_sig, our_sig), preimage: Some(*payment_preimage), amount: htlc.amount_msat / 1000});
1787 //TODO: with option_simplified_commitment track outpoint too
1788 log_trace!(self, "Outpoint {}:{} is being being claimed", htlc_success_tx.input[0].previous_output.vout, htlc_success_tx.input[0].previous_output.txid);
1789 res.push(htlc_success_tx);
1792 watch_outputs.push(local_tx.tx.without_valid_witness().output[transaction_output_index as usize].clone());
1793 } else { panic!("Should have sigs for non-dust local tx outputs!") }
1798 (res, watch_outputs, broadcasted_local_revokable_script)
1801 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1802 /// revoked using data in local_claimable_outpoints.
1803 /// Should not be used if check_spend_revoked_transaction succeeds.
1804 fn check_spend_local_transaction(&mut self, tx: &Transaction, height: u32) -> (Vec<Transaction>, (Sha256dHash, Vec<TxOut>)) {
1805 let commitment_txid = tx.txid();
1806 let mut local_txn = Vec::new();
1807 let mut watch_outputs = Vec::new();
1809 macro_rules! wait_threshold_conf {
1810 ($height: expr, $source: expr, $commitment_tx: expr, $payment_hash: expr) => {
1811 log_trace!(self, "Failing HTLC with payment_hash {} from {} local commitment tx due to broadcast of transaction, waiting confirmation (at height{})", log_bytes!($payment_hash.0), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1812 match self.onchain_events_waiting_threshold_conf.entry($height + ANTI_REORG_DELAY - 1) {
1813 hash_map::Entry::Occupied(mut entry) => {
1814 let e = entry.get_mut();
1815 e.retain(|ref event| {
1817 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1818 return htlc_update.0 != $source
1823 e.push(OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)});
1825 hash_map::Entry::Vacant(entry) => {
1826 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)}]);
1832 macro_rules! append_onchain_update {
1833 ($updates: expr) => {
1834 local_txn.append(&mut $updates.0);
1835 watch_outputs.append(&mut $updates.1);
1836 self.broadcasted_local_revokable_script = $updates.2;
1840 // HTLCs set may differ between last and previous local commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
1841 let mut is_local_tx = false;
1843 if let &mut Some(ref mut local_tx) = &mut self.current_local_signed_commitment_tx {
1844 if local_tx.txid == commitment_txid {
1845 match self.key_storage {
1846 Storage::Local { ref funding_key, .. } => {
1847 local_tx.tx.add_local_sig(funding_key, self.funding_redeemscript.as_ref().unwrap(), self.channel_value_satoshis.unwrap(), &self.secp_ctx);
1853 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1854 if local_tx.txid == commitment_txid {
1856 log_trace!(self, "Got latest local commitment tx broadcast, searching for available HTLCs to claim");
1857 assert!(local_tx.tx.has_local_sig());
1858 match self.key_storage {
1859 Storage::Local { ref delayed_payment_base_key, .. } => {
1860 let mut res = self.broadcast_by_local_state(local_tx, delayed_payment_base_key);
1861 append_onchain_update!(res);
1863 Storage::Watchtower { .. } => { }
1867 if let &mut Some(ref mut local_tx) = &mut self.prev_local_signed_commitment_tx {
1868 if local_tx.txid == commitment_txid {
1869 match self.key_storage {
1870 Storage::Local { ref funding_key, .. } => {
1871 local_tx.tx.add_local_sig(funding_key, self.funding_redeemscript.as_ref().unwrap(), self.channel_value_satoshis.unwrap(), &self.secp_ctx);
1877 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1878 if local_tx.txid == commitment_txid {
1880 log_trace!(self, "Got previous local commitment tx broadcast, searching for available HTLCs to claim");
1881 assert!(local_tx.tx.has_local_sig());
1882 match self.key_storage {
1883 Storage::Local { ref delayed_payment_base_key, .. } => {
1884 let mut res = self.broadcast_by_local_state(local_tx, delayed_payment_base_key);
1885 append_onchain_update!(res);
1887 Storage::Watchtower { .. } => { }
1892 macro_rules! fail_dust_htlcs_after_threshold_conf {
1893 ($local_tx: expr) => {
1894 for &(ref htlc, _, ref source) in &$local_tx.htlc_outputs {
1895 if htlc.transaction_output_index.is_none() {
1896 if let &Some(ref source) = source {
1897 wait_threshold_conf!(height, source.clone(), "lastest", htlc.payment_hash.clone());
1905 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1906 fail_dust_htlcs_after_threshold_conf!(local_tx);
1908 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1909 fail_dust_htlcs_after_threshold_conf!(local_tx);
1913 (local_txn, (commitment_txid, watch_outputs))
1916 /// Used by ChannelManager deserialization to broadcast the latest local state if its copy of
1917 /// the Channel was out-of-date. You may use it to get a broadcastable local toxic tx in case of
1918 /// fallen-behind, i.e when receiving a channel_reestablish with a proof that our remote side knows
1919 /// a higher revocation secret than the local commitment number we are aware of. Broadcasting these
1920 /// transactions are UNSAFE, as they allow remote side to punish you. Nevertheless you may want to
1921 /// broadcast them if remote don't close channel with his higher commitment transaction after a
1922 /// substantial amount of time (a month or even a year) to get back funds. Best may be to contact
1923 /// out-of-band the other node operator to coordinate with him if option is available to you.
1924 /// In any-case, choice is up to the user.
1925 pub fn get_latest_local_commitment_txn(&mut self) -> Vec<Transaction> {
1926 // TODO: We should likely move all of the logic in here into OnChainTxHandler and unify it
1927 // to ensure add_local_sig is only ever called once no matter what. This likely includes
1928 // tracking state and panic!()ing if we get an update after force-closure/local-tx signing.
1929 log_trace!(self, "Getting signed latest local commitment transaction!");
1930 if let &mut Some(ref mut local_tx) = &mut self.current_local_signed_commitment_tx {
1931 match self.key_storage {
1932 Storage::Local { ref funding_key, .. } => {
1933 local_tx.tx.add_local_sig(funding_key, self.funding_redeemscript.as_ref().unwrap(), self.channel_value_satoshis.unwrap(), &self.secp_ctx);
1938 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1939 let mut res = vec![local_tx.tx.with_valid_witness().clone()];
1940 match self.key_storage {
1941 Storage::Local { ref delayed_payment_base_key, .. } => {
1942 res.append(&mut self.broadcast_by_local_state(local_tx, delayed_payment_base_key).0);
1943 // 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.
1944 // The data will be re-generated and tracked in check_spend_local_transaction if we get a confirmation.
1946 _ => panic!("Can only broadcast by local channelmonitor"),
1954 /// Called by SimpleManyChannelMonitor::block_connected, which implements
1955 /// ChainListener::block_connected.
1956 /// Eventually this should be pub and, roughly, implement ChainListener, however this requires
1957 /// &mut self, as well as returns new spendable outputs and outpoints to watch for spending of
1959 fn block_connected<B: Deref, F: Deref>(&mut self, txn_matched: &[&Transaction], height: u32, block_hash: &Sha256dHash, broadcaster: B, fee_estimator: F)-> Vec<(Sha256dHash, Vec<TxOut>)>
1960 where B::Target: BroadcasterInterface,
1961 F::Target: FeeEstimator
1963 for tx in txn_matched {
1964 let mut output_val = 0;
1965 for out in tx.output.iter() {
1966 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1967 output_val += out.value;
1968 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
1972 log_trace!(self, "Block {} at height {} connected with {} txn matched", block_hash, height, txn_matched.len());
1973 let mut watch_outputs = Vec::new();
1974 let mut claimable_outpoints = Vec::new();
1975 for tx in txn_matched {
1976 if tx.input.len() == 1 {
1977 // Assuming our keys were not leaked (in which case we're screwed no matter what),
1978 // commitment transactions and HTLC transactions will all only ever have one input,
1979 // which is an easy way to filter out any potential non-matching txn for lazy
1981 let prevout = &tx.input[0].previous_output;
1982 let funding_txo = match self.key_storage {
1983 Storage::Local { ref funding_info, .. } => {
1984 funding_info.clone()
1986 Storage::Watchtower { .. } => {
1990 if funding_txo.is_none() || (prevout.txid == funding_txo.as_ref().unwrap().0.txid && prevout.vout == funding_txo.as_ref().unwrap().0.index as u32) {
1991 if (tx.input[0].sequence >> 8*3) as u8 == 0x80 && (tx.lock_time >> 8*3) as u8 == 0x20 {
1992 let (mut new_outpoints, new_outputs) = self.check_spend_remote_transaction(&tx, height);
1993 if !new_outputs.1.is_empty() {
1994 watch_outputs.push(new_outputs);
1996 if new_outpoints.is_empty() {
1997 let (local_txn, new_outputs) = self.check_spend_local_transaction(&tx, height);
1998 for tx in local_txn.iter() {
1999 log_trace!(self, "Broadcast onchain {}", log_tx!(tx));
2000 broadcaster.broadcast_transaction(tx);
2002 if !new_outputs.1.is_empty() {
2003 watch_outputs.push(new_outputs);
2006 claimable_outpoints.append(&mut new_outpoints);
2009 if let Some(&(commitment_number, _)) = self.remote_commitment_txn_on_chain.get(&prevout.txid) {
2010 let (mut new_outpoints, new_outputs_option) = self.check_spend_remote_htlc(&tx, commitment_number, height);
2011 claimable_outpoints.append(&mut new_outpoints);
2012 if let Some(new_outputs) = new_outputs_option {
2013 watch_outputs.push(new_outputs);
2018 // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
2019 // can also be resolved in a few other ways which can have more than one output. Thus,
2020 // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
2021 self.is_resolving_htlc_output(&tx, height);
2023 self.is_paying_spendable_output(&tx, height);
2025 let should_broadcast = if let Some(_) = self.current_local_signed_commitment_tx {
2026 self.would_broadcast_at_height(height)
2028 if let Some(ref mut cur_local_tx) = self.current_local_signed_commitment_tx {
2029 if should_broadcast {
2030 match self.key_storage {
2031 Storage::Local { ref funding_key, .. } => {
2032 cur_local_tx.tx.add_local_sig(funding_key, self.funding_redeemscript.as_ref().unwrap(), self.channel_value_satoshis.unwrap(), &self.secp_ctx);
2038 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
2039 if should_broadcast {
2040 log_trace!(self, "Broadcast onchain {}", log_tx!(cur_local_tx.tx.with_valid_witness()));
2041 broadcaster.broadcast_transaction(&cur_local_tx.tx.with_valid_witness());
2042 match self.key_storage {
2043 Storage::Local { ref delayed_payment_base_key, .. } => {
2044 let (txs, new_outputs, _) = self.broadcast_by_local_state(&cur_local_tx, delayed_payment_base_key);
2045 if !new_outputs.is_empty() {
2046 watch_outputs.push((cur_local_tx.txid.clone(), new_outputs));
2049 log_trace!(self, "Broadcast onchain {}", log_tx!(tx));
2050 broadcaster.broadcast_transaction(&tx);
2053 Storage::Watchtower { .. } => { },
2057 if let Some(events) = self.onchain_events_waiting_threshold_conf.remove(&height) {
2060 OnchainEvent::HTLCUpdate { htlc_update } => {
2061 log_trace!(self, "HTLC {} failure update has got enough confirmations to be passed upstream", log_bytes!((htlc_update.1).0));
2062 self.pending_htlcs_updated.push(HTLCUpdate {
2063 payment_hash: htlc_update.1,
2064 payment_preimage: None,
2065 source: htlc_update.0,
2068 OnchainEvent::MaturingOutput { descriptor } => {
2069 log_trace!(self, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
2070 self.pending_events.push(events::Event::SpendableOutputs {
2071 outputs: vec![descriptor]
2077 self.onchain_tx_handler.block_connected(txn_matched, claimable_outpoints, height, &*broadcaster, &*fee_estimator);
2079 self.last_block_hash = block_hash.clone();
2080 for &(ref txid, ref output_scripts) in watch_outputs.iter() {
2081 self.outputs_to_watch.insert(txid.clone(), output_scripts.iter().map(|o| o.script_pubkey.clone()).collect());
2087 fn block_disconnected<B: Deref, F: Deref>(&mut self, height: u32, block_hash: &Sha256dHash, broadcaster: B, fee_estimator: F)
2088 where B::Target: BroadcasterInterface,
2089 F::Target: FeeEstimator
2091 log_trace!(self, "Block {} at height {} disconnected", block_hash, height);
2092 if let Some(_) = self.onchain_events_waiting_threshold_conf.remove(&(height + ANTI_REORG_DELAY - 1)) {
2094 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
2095 //- maturing spendable output has transaction paying us has been disconnected
2098 self.onchain_tx_handler.block_disconnected(height, broadcaster, fee_estimator);
2100 self.last_block_hash = block_hash.clone();
2103 pub(super) fn would_broadcast_at_height(&self, height: u32) -> bool {
2104 // We need to consider all HTLCs which are:
2105 // * in any unrevoked remote commitment transaction, as they could broadcast said
2106 // transactions and we'd end up in a race, or
2107 // * are in our latest local commitment transaction, as this is the thing we will
2108 // broadcast if we go on-chain.
2109 // Note that we consider HTLCs which were below dust threshold here - while they don't
2110 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
2111 // to the source, and if we don't fail the channel we will have to ensure that the next
2112 // updates that peer sends us are update_fails, failing the channel if not. It's probably
2113 // easier to just fail the channel as this case should be rare enough anyway.
2114 macro_rules! scan_commitment {
2115 ($htlcs: expr, $local_tx: expr) => {
2116 for ref htlc in $htlcs {
2117 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
2118 // chain with enough room to claim the HTLC without our counterparty being able to
2119 // time out the HTLC first.
2120 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
2121 // concern is being able to claim the corresponding inbound HTLC (on another
2122 // channel) before it expires. In fact, we don't even really care if our
2123 // counterparty here claims such an outbound HTLC after it expired as long as we
2124 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
2125 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
2126 // we give ourselves a few blocks of headroom after expiration before going
2127 // on-chain for an expired HTLC.
2128 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
2129 // from us until we've reached the point where we go on-chain with the
2130 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
2131 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
2132 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
2133 // inbound_cltv == height + CLTV_CLAIM_BUFFER
2134 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
2135 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
2136 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
2137 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
2138 // The final, above, condition is checked for statically in channelmanager
2139 // with CHECK_CLTV_EXPIRY_SANITY_2.
2140 let htlc_outbound = $local_tx == htlc.offered;
2141 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
2142 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
2143 log_info!(self, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
2150 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
2151 scan_commitment!(cur_local_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
2154 if let Storage::Local { ref current_remote_commitment_txid, ref prev_remote_commitment_txid, .. } = self.key_storage {
2155 if let &Some(ref txid) = current_remote_commitment_txid {
2156 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(txid) {
2157 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2160 if let &Some(ref txid) = prev_remote_commitment_txid {
2161 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(txid) {
2162 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2170 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a local
2171 /// or remote commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
2172 fn is_resolving_htlc_output(&mut self, tx: &Transaction, height: u32) {
2173 'outer_loop: for input in &tx.input {
2174 let mut payment_data = None;
2175 let revocation_sig_claim = (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && input.witness[1].len() == 33)
2176 || (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && input.witness[1].len() == 33);
2177 let accepted_preimage_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::AcceptedHTLC);
2178 let offered_preimage_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC);
2180 macro_rules! log_claim {
2181 ($tx_info: expr, $local_tx: expr, $htlc: expr, $source_avail: expr) => {
2182 // We found the output in question, but aren't failing it backwards
2183 // as we have no corresponding source and no valid remote commitment txid
2184 // to try a weak source binding with same-hash, same-value still-valid offered HTLC.
2185 // This implies either it is an inbound HTLC or an outbound HTLC on a revoked transaction.
2186 let outbound_htlc = $local_tx == $htlc.offered;
2187 if ($local_tx && revocation_sig_claim) ||
2188 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
2189 log_error!(self, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
2190 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2191 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2192 if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back" });
2194 log_info!(self, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
2195 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2196 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2197 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
2202 macro_rules! check_htlc_valid_remote {
2203 ($remote_txid: expr, $htlc_output: expr) => {
2204 if let &Some(txid) = $remote_txid {
2205 for &(ref pending_htlc, ref pending_source) in self.remote_claimable_outpoints.get(&txid).unwrap() {
2206 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
2207 if let &Some(ref source) = pending_source {
2208 log_claim!("revoked remote commitment tx", false, pending_htlc, true);
2209 payment_data = Some(((**source).clone(), $htlc_output.payment_hash));
2218 macro_rules! scan_commitment {
2219 ($htlcs: expr, $tx_info: expr, $local_tx: expr) => {
2220 for (ref htlc_output, source_option) in $htlcs {
2221 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
2222 if let Some(ref source) = source_option {
2223 log_claim!($tx_info, $local_tx, htlc_output, true);
2224 // We have a resolution of an HTLC either from one of our latest
2225 // local commitment transactions or an unrevoked remote commitment
2226 // transaction. This implies we either learned a preimage, the HTLC
2227 // has timed out, or we screwed up. In any case, we should now
2228 // resolve the source HTLC with the original sender.
2229 payment_data = Some(((*source).clone(), htlc_output.payment_hash));
2230 } else if !$local_tx {
2231 if let Storage::Local { ref current_remote_commitment_txid, .. } = self.key_storage {
2232 check_htlc_valid_remote!(current_remote_commitment_txid, htlc_output);
2234 if payment_data.is_none() {
2235 if let Storage::Local { ref prev_remote_commitment_txid, .. } = self.key_storage {
2236 check_htlc_valid_remote!(prev_remote_commitment_txid, htlc_output);
2240 if payment_data.is_none() {
2241 log_claim!($tx_info, $local_tx, htlc_output, false);
2242 continue 'outer_loop;
2249 if let Some(ref current_local_signed_commitment_tx) = self.current_local_signed_commitment_tx {
2250 if input.previous_output.txid == current_local_signed_commitment_tx.txid {
2251 scan_commitment!(current_local_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2252 "our latest local commitment tx", true);
2255 if let Some(ref prev_local_signed_commitment_tx) = self.prev_local_signed_commitment_tx {
2256 if input.previous_output.txid == prev_local_signed_commitment_tx.txid {
2257 scan_commitment!(prev_local_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2258 "our previous local commitment tx", true);
2261 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(&input.previous_output.txid) {
2262 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
2263 "remote commitment tx", false);
2266 // Check that scan_commitment, above, decided there is some source worth relaying an
2267 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
2268 if let Some((source, payment_hash)) = payment_data {
2269 let mut payment_preimage = PaymentPreimage([0; 32]);
2270 if accepted_preimage_claim {
2271 if !self.pending_htlcs_updated.iter().any(|update| update.source == source) {
2272 payment_preimage.0.copy_from_slice(&input.witness[3]);
2273 self.pending_htlcs_updated.push(HTLCUpdate {
2275 payment_preimage: Some(payment_preimage),
2279 } else if offered_preimage_claim {
2280 if !self.pending_htlcs_updated.iter().any(|update| update.source == source) {
2281 payment_preimage.0.copy_from_slice(&input.witness[1]);
2282 self.pending_htlcs_updated.push(HTLCUpdate {
2284 payment_preimage: Some(payment_preimage),
2289 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);
2290 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2291 hash_map::Entry::Occupied(mut entry) => {
2292 let e = entry.get_mut();
2293 e.retain(|ref event| {
2295 OnchainEvent::HTLCUpdate { ref htlc_update } => {
2296 return htlc_update.0 != source
2301 e.push(OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)});
2303 hash_map::Entry::Vacant(entry) => {
2304 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)}]);
2312 /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
2313 fn is_paying_spendable_output(&mut self, tx: &Transaction, height: u32) {
2314 let mut spendable_output = None;
2315 for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
2316 if outp.script_pubkey == self.destination_script {
2317 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2318 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2319 output: outp.clone(),
2322 } else if let Some(ref broadcasted_local_revokable_script) = self.broadcasted_local_revokable_script {
2323 if broadcasted_local_revokable_script.0 == outp.script_pubkey {
2324 spendable_output = Some(SpendableOutputDescriptor::DynamicOutputP2WSH {
2325 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2326 key: broadcasted_local_revokable_script.1,
2327 witness_script: broadcasted_local_revokable_script.2.clone(),
2328 to_self_delay: self.their_to_self_delay.unwrap(),
2329 output: outp.clone(),
2333 } else if let Some(ref broadcasted_remote_payment_script) = self.broadcasted_remote_payment_script {
2334 if broadcasted_remote_payment_script.0 == outp.script_pubkey {
2335 spendable_output = Some(SpendableOutputDescriptor::DynamicOutputP2WPKH {
2336 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2337 key: broadcasted_remote_payment_script.1,
2338 output: outp.clone(),
2342 } else if outp.script_pubkey == self.shutdown_script {
2343 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2344 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: i as u32 },
2345 output: outp.clone(),
2349 if let Some(spendable_output) = spendable_output {
2350 log_trace!(self, "Maturing {} until {}", log_spendable!(spendable_output), height + ANTI_REORG_DELAY - 1);
2351 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2352 hash_map::Entry::Occupied(mut entry) => {
2353 let e = entry.get_mut();
2354 e.push(OnchainEvent::MaturingOutput { descriptor: spendable_output });
2356 hash_map::Entry::Vacant(entry) => {
2357 entry.insert(vec![OnchainEvent::MaturingOutput { descriptor: spendable_output }]);
2364 const MAX_ALLOC_SIZE: usize = 64*1024;
2366 impl<ChanSigner: ChannelKeys + Readable> ReadableArgs<Arc<Logger>> for (Sha256dHash, ChannelMonitor<ChanSigner>) {
2367 fn read<R: ::std::io::Read>(reader: &mut R, logger: Arc<Logger>) -> Result<Self, DecodeError> {
2368 macro_rules! unwrap_obj {
2372 Err(_) => return Err(DecodeError::InvalidValue),
2377 let _ver: u8 = Readable::read(reader)?;
2378 let min_ver: u8 = Readable::read(reader)?;
2379 if min_ver > SERIALIZATION_VERSION {
2380 return Err(DecodeError::UnknownVersion);
2383 let latest_update_id: u64 = Readable::read(reader)?;
2384 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
2386 let destination_script = Readable::read(reader)?;
2387 let broadcasted_local_revokable_script = match <u8 as Readable>::read(reader)? {
2389 let revokable_address = Readable::read(reader)?;
2390 let local_delayedkey = Readable::read(reader)?;
2391 let revokable_script = Readable::read(reader)?;
2392 Some((revokable_address, local_delayedkey, revokable_script))
2395 _ => return Err(DecodeError::InvalidValue),
2397 let broadcasted_remote_payment_script = match <u8 as Readable>::read(reader)? {
2399 let payment_address = Readable::read(reader)?;
2400 let payment_key = Readable::read(reader)?;
2401 Some((payment_address, payment_key))
2404 _ => return Err(DecodeError::InvalidValue),
2406 let shutdown_script = Readable::read(reader)?;
2408 let key_storage = match <u8 as Readable>::read(reader)? {
2410 let keys = Readable::read(reader)?;
2411 let funding_key = Readable::read(reader)?;
2412 let revocation_base_key = Readable::read(reader)?;
2413 let htlc_base_key = Readable::read(reader)?;
2414 let delayed_payment_base_key = Readable::read(reader)?;
2415 let payment_base_key = Readable::read(reader)?;
2416 // Technically this can fail and serialize fail a round-trip, but only for serialization of
2417 // barely-init'd ChannelMonitors that we can't do anything with.
2418 let outpoint = OutPoint {
2419 txid: Readable::read(reader)?,
2420 index: Readable::read(reader)?,
2422 let funding_info = Some((outpoint, Readable::read(reader)?));
2423 let current_remote_commitment_txid = Readable::read(reader)?;
2424 let prev_remote_commitment_txid = Readable::read(reader)?;
2428 revocation_base_key,
2430 delayed_payment_base_key,
2433 current_remote_commitment_txid,
2434 prev_remote_commitment_txid,
2437 _ => return Err(DecodeError::InvalidValue),
2440 let their_htlc_base_key = Some(Readable::read(reader)?);
2441 let their_delayed_payment_base_key = Some(Readable::read(reader)?);
2442 let funding_redeemscript = Some(Readable::read(reader)?);
2443 let channel_value_satoshis = Some(Readable::read(reader)?);
2445 let their_cur_revocation_points = {
2446 let first_idx = <U48 as Readable>::read(reader)?.0;
2450 let first_point = Readable::read(reader)?;
2451 let second_point_slice: [u8; 33] = Readable::read(reader)?;
2452 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
2453 Some((first_idx, first_point, None))
2455 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
2460 let our_to_self_delay: u16 = Readable::read(reader)?;
2461 let their_to_self_delay: Option<u16> = Some(Readable::read(reader)?);
2463 let commitment_secrets = Readable::read(reader)?;
2465 macro_rules! read_htlc_in_commitment {
2468 let offered: bool = Readable::read(reader)?;
2469 let amount_msat: u64 = Readable::read(reader)?;
2470 let cltv_expiry: u32 = Readable::read(reader)?;
2471 let payment_hash: PaymentHash = Readable::read(reader)?;
2472 let transaction_output_index: Option<u32> = Readable::read(reader)?;
2474 HTLCOutputInCommitment {
2475 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
2481 let remote_claimable_outpoints_len: u64 = Readable::read(reader)?;
2482 let mut remote_claimable_outpoints = HashMap::with_capacity(cmp::min(remote_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
2483 for _ in 0..remote_claimable_outpoints_len {
2484 let txid: Sha256dHash = Readable::read(reader)?;
2485 let htlcs_count: u64 = Readable::read(reader)?;
2486 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
2487 for _ in 0..htlcs_count {
2488 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
2490 if let Some(_) = remote_claimable_outpoints.insert(txid, htlcs) {
2491 return Err(DecodeError::InvalidValue);
2495 let remote_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
2496 let mut remote_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(remote_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
2497 for _ in 0..remote_commitment_txn_on_chain_len {
2498 let txid: Sha256dHash = Readable::read(reader)?;
2499 let commitment_number = <U48 as Readable>::read(reader)?.0;
2500 let outputs_count = <u64 as Readable>::read(reader)?;
2501 let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 8));
2502 for _ in 0..outputs_count {
2503 outputs.push(Readable::read(reader)?);
2505 if let Some(_) = remote_commitment_txn_on_chain.insert(txid, (commitment_number, outputs)) {
2506 return Err(DecodeError::InvalidValue);
2510 let remote_hash_commitment_number_len: u64 = Readable::read(reader)?;
2511 let mut remote_hash_commitment_number = HashMap::with_capacity(cmp::min(remote_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
2512 for _ in 0..remote_hash_commitment_number_len {
2513 let payment_hash: PaymentHash = Readable::read(reader)?;
2514 let commitment_number = <U48 as Readable>::read(reader)?.0;
2515 if let Some(_) = remote_hash_commitment_number.insert(payment_hash, commitment_number) {
2516 return Err(DecodeError::InvalidValue);
2520 macro_rules! read_local_tx {
2523 let tx = <LocalCommitmentTransaction as Readable>::read(reader)?;
2524 let revocation_key = Readable::read(reader)?;
2525 let a_htlc_key = Readable::read(reader)?;
2526 let b_htlc_key = Readable::read(reader)?;
2527 let delayed_payment_key = Readable::read(reader)?;
2528 let per_commitment_point = Readable::read(reader)?;
2529 let feerate_per_kw: u64 = Readable::read(reader)?;
2531 let htlcs_len: u64 = Readable::read(reader)?;
2532 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_len as usize, MAX_ALLOC_SIZE / 128));
2533 for _ in 0..htlcs_len {
2534 let htlc = read_htlc_in_commitment!();
2535 let sigs = match <u8 as Readable>::read(reader)? {
2537 1 => Some(Readable::read(reader)?),
2538 _ => return Err(DecodeError::InvalidValue),
2540 htlcs.push((htlc, sigs, Readable::read(reader)?));
2545 tx, revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, per_commitment_point, feerate_per_kw,
2552 let prev_local_signed_commitment_tx = match <u8 as Readable>::read(reader)? {
2555 Some(read_local_tx!())
2557 _ => return Err(DecodeError::InvalidValue),
2560 let current_local_signed_commitment_tx = match <u8 as Readable>::read(reader)? {
2563 Some(read_local_tx!())
2565 _ => return Err(DecodeError::InvalidValue),
2568 let current_remote_commitment_number = <U48 as Readable>::read(reader)?.0;
2570 let payment_preimages_len: u64 = Readable::read(reader)?;
2571 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
2572 for _ in 0..payment_preimages_len {
2573 let preimage: PaymentPreimage = Readable::read(reader)?;
2574 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2575 if let Some(_) = payment_preimages.insert(hash, preimage) {
2576 return Err(DecodeError::InvalidValue);
2580 let pending_htlcs_updated_len: u64 = Readable::read(reader)?;
2581 let mut pending_htlcs_updated = Vec::with_capacity(cmp::min(pending_htlcs_updated_len as usize, MAX_ALLOC_SIZE / (32 + 8*3)));
2582 for _ in 0..pending_htlcs_updated_len {
2583 pending_htlcs_updated.push(Readable::read(reader)?);
2586 let pending_events_len: u64 = Readable::read(reader)?;
2587 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<events::Event>()));
2588 for _ in 0..pending_events_len {
2589 if let Some(event) = MaybeReadable::read(reader)? {
2590 pending_events.push(event);
2594 let last_block_hash: Sha256dHash = Readable::read(reader)?;
2596 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
2597 let mut onchain_events_waiting_threshold_conf = HashMap::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
2598 for _ in 0..waiting_threshold_conf_len {
2599 let height_target = Readable::read(reader)?;
2600 let events_len: u64 = Readable::read(reader)?;
2601 let mut events = Vec::with_capacity(cmp::min(events_len as usize, MAX_ALLOC_SIZE / 128));
2602 for _ in 0..events_len {
2603 let ev = match <u8 as Readable>::read(reader)? {
2605 let htlc_source = Readable::read(reader)?;
2606 let hash = Readable::read(reader)?;
2607 OnchainEvent::HTLCUpdate {
2608 htlc_update: (htlc_source, hash)
2612 let descriptor = Readable::read(reader)?;
2613 OnchainEvent::MaturingOutput {
2617 _ => return Err(DecodeError::InvalidValue),
2621 onchain_events_waiting_threshold_conf.insert(height_target, events);
2624 let outputs_to_watch_len: u64 = Readable::read(reader)?;
2625 let mut outputs_to_watch = HashMap::with_capacity(cmp::min(outputs_to_watch_len as usize, MAX_ALLOC_SIZE / (mem::size_of::<Sha256dHash>() + mem::size_of::<Vec<Script>>())));
2626 for _ in 0..outputs_to_watch_len {
2627 let txid = Readable::read(reader)?;
2628 let outputs_len: u64 = Readable::read(reader)?;
2629 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Script>()));
2630 for _ in 0..outputs_len {
2631 outputs.push(Readable::read(reader)?);
2633 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
2634 return Err(DecodeError::InvalidValue);
2637 let onchain_tx_handler = ReadableArgs::read(reader, logger.clone())?;
2639 Ok((last_block_hash.clone(), ChannelMonitor {
2641 commitment_transaction_number_obscure_factor,
2644 broadcasted_local_revokable_script,
2645 broadcasted_remote_payment_script,
2649 their_htlc_base_key,
2650 their_delayed_payment_base_key,
2651 funding_redeemscript,
2652 channel_value_satoshis,
2653 their_cur_revocation_points,
2656 their_to_self_delay,
2659 remote_claimable_outpoints,
2660 remote_commitment_txn_on_chain,
2661 remote_hash_commitment_number,
2663 prev_local_signed_commitment_tx,
2664 current_local_signed_commitment_tx,
2665 current_remote_commitment_number,
2668 pending_htlcs_updated,
2671 onchain_events_waiting_threshold_conf,
2677 secp_ctx: Secp256k1::new(),
2685 use bitcoin::blockdata::script::{Script, Builder};
2686 use bitcoin::blockdata::opcodes;
2687 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, SigHashType};
2688 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
2689 use bitcoin::util::bip143;
2690 use bitcoin_hashes::Hash;
2691 use bitcoin_hashes::sha256::Hash as Sha256;
2692 use bitcoin_hashes::sha256d::Hash as Sha256dHash;
2693 use bitcoin_hashes::hex::FromHex;
2695 use chain::transaction::OutPoint;
2696 use ln::channelmanager::{PaymentPreimage, PaymentHash};
2697 use ln::channelmonitor::ChannelMonitor;
2698 use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
2700 use ln::chan_utils::{HTLCOutputInCommitment, TxCreationKeys, LocalCommitmentTransaction};
2701 use util::test_utils::TestLogger;
2702 use secp256k1::key::{SecretKey,PublicKey};
2703 use secp256k1::Secp256k1;
2704 use rand::{thread_rng,Rng};
2706 use chain::keysinterface::InMemoryChannelKeys;
2709 fn test_prune_preimages() {
2710 let secp_ctx = Secp256k1::new();
2711 let logger = Arc::new(TestLogger::new());
2713 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
2714 macro_rules! dummy_keys {
2718 per_commitment_point: dummy_key.clone(),
2719 revocation_key: dummy_key.clone(),
2720 a_htlc_key: dummy_key.clone(),
2721 b_htlc_key: dummy_key.clone(),
2722 a_delayed_payment_key: dummy_key.clone(),
2723 b_payment_key: dummy_key.clone(),
2728 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2730 let mut preimages = Vec::new();
2732 let mut rng = thread_rng();
2734 let mut preimage = PaymentPreimage([0; 32]);
2735 rng.fill_bytes(&mut preimage.0[..]);
2736 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2737 preimages.push((preimage, hash));
2741 macro_rules! preimages_slice_to_htlc_outputs {
2742 ($preimages_slice: expr) => {
2744 let mut res = Vec::new();
2745 for (idx, preimage) in $preimages_slice.iter().enumerate() {
2746 res.push((HTLCOutputInCommitment {
2750 payment_hash: preimage.1.clone(),
2751 transaction_output_index: Some(idx as u32),
2758 macro_rules! preimages_to_local_htlcs {
2759 ($preimages_slice: expr) => {
2761 let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2762 let res: Vec<_> = inp.drain(..).map(|e| { (e.0, None, e.1) }).collect();
2768 macro_rules! test_preimages_exist {
2769 ($preimages_slice: expr, $monitor: expr) => {
2770 for preimage in $preimages_slice {
2771 assert!($monitor.payment_preimages.contains_key(&preimage.1));
2776 let keys = InMemoryChannelKeys::new(
2778 SecretKey::from_slice(&[41; 32]).unwrap(),
2779 SecretKey::from_slice(&[41; 32]).unwrap(),
2780 SecretKey::from_slice(&[41; 32]).unwrap(),
2781 SecretKey::from_slice(&[41; 32]).unwrap(),
2782 SecretKey::from_slice(&[41; 32]).unwrap(),
2787 // Prune with one old state and a local commitment tx holding a few overlaps with the
2789 let mut monitor = ChannelMonitor::new(keys,
2790 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()), 0, &Script::new(),
2791 (OutPoint { txid: Sha256dHash::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
2792 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
2793 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
2794 0, Script::new(), 46, 0, logger.clone());
2796 monitor.their_to_self_delay = Some(10);
2798 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..10])).unwrap();
2799 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key);
2800 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key);
2801 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key);
2802 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key);
2803 for &(ref preimage, ref hash) in preimages.iter() {
2804 monitor.provide_payment_preimage(hash, preimage);
2807 // Now provide a secret, pruning preimages 10-15
2808 let mut secret = [0; 32];
2809 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2810 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2811 assert_eq!(monitor.payment_preimages.len(), 15);
2812 test_preimages_exist!(&preimages[0..10], monitor);
2813 test_preimages_exist!(&preimages[15..20], monitor);
2815 // Now provide a further secret, pruning preimages 15-17
2816 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2817 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2818 assert_eq!(monitor.payment_preimages.len(), 13);
2819 test_preimages_exist!(&preimages[0..10], monitor);
2820 test_preimages_exist!(&preimages[17..20], monitor);
2822 // Now update local commitment tx info, pruning only element 18 as we still care about the
2823 // previous commitment tx's preimages too
2824 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..5])).unwrap();
2825 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2826 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2827 assert_eq!(monitor.payment_preimages.len(), 12);
2828 test_preimages_exist!(&preimages[0..10], monitor);
2829 test_preimages_exist!(&preimages[18..20], monitor);
2831 // But if we do it again, we'll prune 5-10
2832 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..3])).unwrap();
2833 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2834 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2835 assert_eq!(monitor.payment_preimages.len(), 5);
2836 test_preimages_exist!(&preimages[0..5], monitor);
2840 fn test_claim_txn_weight_computation() {
2841 // We test Claim txn weight, knowing that we want expected weigth and
2842 // not actual case to avoid sigs and time-lock delays hell variances.
2844 let secp_ctx = Secp256k1::new();
2845 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
2846 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
2847 let mut sum_actual_sigs = 0;
2849 macro_rules! sign_input {
2850 ($sighash_parts: expr, $input: expr, $idx: expr, $amount: expr, $input_type: expr, $sum_actual_sigs: expr) => {
2851 let htlc = HTLCOutputInCommitment {
2852 offered: if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::OfferedHTLC { true } else { false },
2854 cltv_expiry: 2 << 16,
2855 payment_hash: PaymentHash([1; 32]),
2856 transaction_output_index: Some($idx),
2858 let redeem_script = if *$input_type == InputDescriptors::RevokedOutput { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &pubkey, &pubkey, &pubkey) };
2859 let sighash = hash_to_message!(&$sighash_parts.sighash_all(&$input, &redeem_script, $amount)[..]);
2860 let sig = secp_ctx.sign(&sighash, &privkey);
2861 $input.witness.push(sig.serialize_der().to_vec());
2862 $input.witness[0].push(SigHashType::All as u8);
2863 sum_actual_sigs += $input.witness[0].len();
2864 if *$input_type == InputDescriptors::RevokedOutput {
2865 $input.witness.push(vec!(1));
2866 } else if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::RevokedReceivedHTLC {
2867 $input.witness.push(pubkey.clone().serialize().to_vec());
2868 } else if *$input_type == InputDescriptors::ReceivedHTLC {
2869 $input.witness.push(vec![0]);
2871 $input.witness.push(PaymentPreimage([1; 32]).0.to_vec());
2873 $input.witness.push(redeem_script.into_bytes());
2874 println!("witness[0] {}", $input.witness[0].len());
2875 println!("witness[1] {}", $input.witness[1].len());
2876 println!("witness[2] {}", $input.witness[2].len());
2880 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
2881 let txid = Sha256dHash::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
2883 // Justice tx with 1 to_local, 2 revoked offered HTLCs, 1 revoked received HTLCs
2884 let mut claim_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2886 claim_tx.input.push(TxIn {
2887 previous_output: BitcoinOutPoint {
2891 script_sig: Script::new(),
2892 sequence: 0xfffffffd,
2893 witness: Vec::new(),
2896 claim_tx.output.push(TxOut {
2897 script_pubkey: script_pubkey.clone(),
2900 let base_weight = claim_tx.get_weight();
2901 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2902 let inputs_des = vec![InputDescriptors::RevokedOutput, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedReceivedHTLC];
2903 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2904 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2906 assert_eq!(base_weight + OnchainTxHandler::get_witnesses_weight(&inputs_des[..]), claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_des.len() - sum_actual_sigs));
2908 // Claim tx with 1 offered HTLCs, 3 received HTLCs
2909 claim_tx.input.clear();
2910 sum_actual_sigs = 0;
2912 claim_tx.input.push(TxIn {
2913 previous_output: BitcoinOutPoint {
2917 script_sig: Script::new(),
2918 sequence: 0xfffffffd,
2919 witness: Vec::new(),
2922 let base_weight = claim_tx.get_weight();
2923 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2924 let inputs_des = vec![InputDescriptors::OfferedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC];
2925 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2926 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2928 assert_eq!(base_weight + OnchainTxHandler::get_witnesses_weight(&inputs_des[..]), claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_des.len() - sum_actual_sigs));
2930 // Justice tx with 1 revoked HTLC-Success tx output
2931 claim_tx.input.clear();
2932 sum_actual_sigs = 0;
2933 claim_tx.input.push(TxIn {
2934 previous_output: BitcoinOutPoint {
2938 script_sig: Script::new(),
2939 sequence: 0xfffffffd,
2940 witness: Vec::new(),
2942 let base_weight = claim_tx.get_weight();
2943 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2944 let inputs_des = vec![InputDescriptors::RevokedOutput];
2945 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2946 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2948 assert_eq!(base_weight + OnchainTxHandler::get_witnesses_weight(&inputs_des[..]), claim_tx.get_weight() + /* max_length_isg */ (73 * inputs_des.len() - sum_actual_sigs));
2951 // Further testing is done in the ChannelManager integration tests.