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 latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date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 shutdown_pubkey: PublicKey,
410 funding_info: Option<(OutPoint, Script)>,
411 current_remote_commitment_txid: Option<Sha256dHash>,
412 prev_remote_commitment_txid: Option<Sha256dHash>,
415 revocation_base_key: PublicKey,
416 htlc_base_key: PublicKey,
420 #[cfg(any(test, feature = "fuzztarget"))]
421 impl<ChanSigner: ChannelKeys> PartialEq for Storage<ChanSigner> {
422 fn eq(&self, other: &Self) -> bool {
424 Storage::Local { ref keys, .. } => {
427 Storage::Local { ref keys, .. } => keys.pubkeys() == k.pubkeys(),
428 Storage::Watchtower { .. } => false,
431 Storage::Watchtower {ref revocation_base_key, ref htlc_base_key} => {
432 let (rbk, hbk) = (revocation_base_key, htlc_base_key);
434 Storage::Local { .. } => false,
435 Storage::Watchtower {ref revocation_base_key, ref htlc_base_key} =>
436 revocation_base_key == rbk && htlc_base_key == hbk,
443 #[derive(Clone, PartialEq)]
444 struct LocalSignedTx {
445 /// txid of the transaction in tx, just used to make comparison faster
447 tx: LocalCommitmentTransaction,
448 revocation_key: PublicKey,
449 a_htlc_key: PublicKey,
450 b_htlc_key: PublicKey,
451 delayed_payment_key: PublicKey,
452 per_commitment_point: PublicKey,
454 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
457 /// When ChannelMonitor discovers an onchain outpoint being a step of a channel and that it needs
458 /// to generate a tx to push channel state forward, we cache outpoint-solving tx material to build
459 /// a new bumped one in case of lenghty confirmation delay
460 #[derive(Clone, PartialEq)]
461 pub(crate) enum InputMaterial {
463 witness_script: Script,
464 pubkey: Option<PublicKey>,
470 witness_script: Script,
472 preimage: Option<PaymentPreimage>,
477 witness_script: Script,
478 sigs: (Signature, Signature),
479 preimage: Option<PaymentPreimage>,
484 impl Writeable for InputMaterial {
485 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
487 &InputMaterial::Revoked { ref witness_script, ref pubkey, ref key, ref is_htlc, ref amount} => {
488 writer.write_all(&[0; 1])?;
489 witness_script.write(writer)?;
490 pubkey.write(writer)?;
491 writer.write_all(&key[..])?;
492 is_htlc.write(writer)?;
493 writer.write_all(&byte_utils::be64_to_array(*amount))?;
495 &InputMaterial::RemoteHTLC { ref witness_script, ref key, ref preimage, ref amount, ref locktime } => {
496 writer.write_all(&[1; 1])?;
497 witness_script.write(writer)?;
499 preimage.write(writer)?;
500 writer.write_all(&byte_utils::be64_to_array(*amount))?;
501 writer.write_all(&byte_utils::be32_to_array(*locktime))?;
503 &InputMaterial::LocalHTLC { ref witness_script, ref sigs, ref preimage, ref amount } => {
504 writer.write_all(&[2; 1])?;
505 witness_script.write(writer)?;
506 sigs.0.write(writer)?;
507 sigs.1.write(writer)?;
508 preimage.write(writer)?;
509 writer.write_all(&byte_utils::be64_to_array(*amount))?;
516 impl Readable for InputMaterial {
517 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
518 let input_material = match <u8 as Readable>::read(reader)? {
520 let witness_script = Readable::read(reader)?;
521 let pubkey = Readable::read(reader)?;
522 let key = Readable::read(reader)?;
523 let is_htlc = Readable::read(reader)?;
524 let amount = Readable::read(reader)?;
525 InputMaterial::Revoked {
534 let witness_script = Readable::read(reader)?;
535 let key = Readable::read(reader)?;
536 let preimage = Readable::read(reader)?;
537 let amount = Readable::read(reader)?;
538 let locktime = Readable::read(reader)?;
539 InputMaterial::RemoteHTLC {
548 let witness_script = Readable::read(reader)?;
549 let their_sig = Readable::read(reader)?;
550 let our_sig = Readable::read(reader)?;
551 let preimage = Readable::read(reader)?;
552 let amount = Readable::read(reader)?;
553 InputMaterial::LocalHTLC {
555 sigs: (their_sig, our_sig),
560 _ => return Err(DecodeError::InvalidValue),
566 /// ClaimRequest is a descriptor structure to communicate between detection
567 /// and reaction module. They are generated by ChannelMonitor while parsing
568 /// onchain txn leaked from a channel and handed over to OnchainTxHandler which
569 /// is responsible for opportunistic aggregation, selecting and enforcing
570 /// bumping logic, building and signing transactions.
571 pub(crate) struct ClaimRequest {
572 // Block height before which claiming is exclusive to one party,
573 // after reaching it, claiming may be contentious.
574 pub(crate) absolute_timelock: u32,
575 // Timeout tx must have nLocktime set which means aggregating multiple
576 // ones must take the higher nLocktime among them to satisfy all of them.
577 // Sadly it has few pitfalls, a) it takes longuer to get fund back b) CLTV_DELTA
578 // of a sooner-HTLC could be swallowed by the highest nLocktime of the HTLC set.
579 // Do simplify we mark them as non-aggregable.
580 pub(crate) aggregable: bool,
581 // Basic bitcoin outpoint (txid, vout)
582 pub(crate) outpoint: BitcoinOutPoint,
583 // Following outpoint type, set of data needed to generate transaction digest
584 // and satisfy witness program.
585 pub(crate) witness_data: InputMaterial
588 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
589 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
590 #[derive(Clone, PartialEq)]
592 /// HTLC output getting solved by a timeout, at maturation we pass upstream payment source information to solve
593 /// inbound HTLC in backward channel. Note, in case of preimage, we pass info to upstream without delay as we can
594 /// only win from it, so it's never an OnchainEvent
596 htlc_update: (HTLCSource, PaymentHash),
600 const SERIALIZATION_VERSION: u8 = 1;
601 const MIN_SERIALIZATION_VERSION: u8 = 1;
603 #[cfg_attr(test, derive(PartialEq))]
605 pub(super) enum ChannelMonitorUpdateStep {
606 LatestLocalCommitmentTXInfo {
607 // TODO: We really need to not be generating a fully-signed transaction in Channel and
608 // passing it here, we need to hold off so that the ChanSigner can enforce a
609 // only-sign-local-state-for-broadcast once invariant:
610 commitment_tx: LocalCommitmentTransaction,
611 local_keys: chan_utils::TxCreationKeys,
613 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
615 LatestRemoteCommitmentTXInfo {
616 unsigned_commitment_tx: Transaction, // TODO: We should actually only need the txid here
617 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
618 commitment_number: u64,
619 their_revocation_point: PublicKey,
622 payment_preimage: PaymentPreimage,
628 /// Indicates our channel is likely a stale version, we're closing, but this update should
629 /// allow us to spend what is ours if our counterparty broadcasts their latest state.
630 RescueRemoteCommitmentTXInfo {
631 their_current_per_commitment_point: PublicKey,
633 /// Used to indicate that the no future updates will occur, and likely that the latest local
634 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
636 /// If set to false, we shouldn't broadcast the latest local commitment transaction as we
637 /// think we've fallen behind!
638 should_broadcast: bool,
642 impl Writeable for ChannelMonitorUpdateStep {
643 fn write<W: Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {
645 &ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { ref commitment_tx, ref local_keys, ref feerate_per_kw, ref htlc_outputs } => {
647 commitment_tx.write(w)?;
648 local_keys.write(w)?;
649 feerate_per_kw.write(w)?;
650 (htlc_outputs.len() as u64).write(w)?;
651 for &(ref output, ref signature, ref source) in htlc_outputs.iter() {
657 &ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { ref unsigned_commitment_tx, ref htlc_outputs, ref commitment_number, ref their_revocation_point } => {
659 unsigned_commitment_tx.write(w)?;
660 commitment_number.write(w)?;
661 their_revocation_point.write(w)?;
662 (htlc_outputs.len() as u64).write(w)?;
663 for &(ref output, ref source) in htlc_outputs.iter() {
665 source.as_ref().map(|b| b.as_ref()).write(w)?;
668 &ChannelMonitorUpdateStep::PaymentPreimage { ref payment_preimage } => {
670 payment_preimage.write(w)?;
672 &ChannelMonitorUpdateStep::CommitmentSecret { ref idx, ref secret } => {
677 &ChannelMonitorUpdateStep::RescueRemoteCommitmentTXInfo { ref their_current_per_commitment_point } => {
679 their_current_per_commitment_point.write(w)?;
681 &ChannelMonitorUpdateStep::ChannelForceClosed { ref should_broadcast } => {
683 should_broadcast.write(w)?;
689 impl Readable for ChannelMonitorUpdateStep {
690 fn read<R: ::std::io::Read>(r: &mut R) -> Result<Self, DecodeError> {
691 match Readable::read(r)? {
693 Ok(ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo {
694 commitment_tx: Readable::read(r)?,
695 local_keys: Readable::read(r)?,
696 feerate_per_kw: Readable::read(r)?,
698 let len: u64 = Readable::read(r)?;
699 let mut res = Vec::new();
701 res.push((Readable::read(r)?, Readable::read(r)?, Readable::read(r)?));
708 Ok(ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo {
709 unsigned_commitment_tx: Readable::read(r)?,
710 commitment_number: Readable::read(r)?,
711 their_revocation_point: Readable::read(r)?,
713 let len: u64 = Readable::read(r)?;
714 let mut res = Vec::new();
716 res.push((Readable::read(r)?, <Option<HTLCSource> as Readable>::read(r)?.map(|o| Box::new(o))));
723 Ok(ChannelMonitorUpdateStep::PaymentPreimage {
724 payment_preimage: Readable::read(r)?,
728 Ok(ChannelMonitorUpdateStep::CommitmentSecret {
729 idx: Readable::read(r)?,
730 secret: Readable::read(r)?,
734 Ok(ChannelMonitorUpdateStep::RescueRemoteCommitmentTXInfo {
735 their_current_per_commitment_point: Readable::read(r)?,
739 Ok(ChannelMonitorUpdateStep::ChannelForceClosed {
740 should_broadcast: Readable::read(r)?
743 _ => Err(DecodeError::InvalidValue),
748 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
749 /// on-chain transactions to ensure no loss of funds occurs.
751 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
752 /// information and are actively monitoring the chain.
754 /// Pending Events or updated HTLCs which have not yet been read out by
755 /// get_and_clear_pending_htlcs_updated or get_and_clear_pending_events are serialized to disk and
756 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
757 /// gotten are fully handled before re-serializing the new state.
758 pub struct ChannelMonitor<ChanSigner: ChannelKeys> {
759 latest_update_id: u64,
760 commitment_transaction_number_obscure_factor: u64,
762 key_storage: Storage<ChanSigner>,
763 their_htlc_base_key: Option<PublicKey>,
764 their_delayed_payment_base_key: Option<PublicKey>,
765 funding_redeemscript: Option<Script>,
766 channel_value_satoshis: Option<u64>,
767 // first is the idx of the first of the two revocation points
768 their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
770 our_to_self_delay: u16,
771 their_to_self_delay: Option<u16>,
773 commitment_secrets: CounterpartyCommitmentSecrets,
774 remote_claimable_outpoints: HashMap<Sha256dHash, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
775 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
776 /// Nor can we figure out their commitment numbers without the commitment transaction they are
777 /// spending. Thus, in order to claim them via revocation key, we track all the remote
778 /// commitment transactions which we find on-chain, mapping them to the commitment number which
779 /// can be used to derive the revocation key and claim the transactions.
780 remote_commitment_txn_on_chain: HashMap<Sha256dHash, (u64, Vec<Script>)>,
781 /// Cache used to make pruning of payment_preimages faster.
782 /// Maps payment_hash values to commitment numbers for remote transactions for non-revoked
783 /// remote transactions (ie should remain pretty small).
784 /// Serialized to disk but should generally not be sent to Watchtowers.
785 remote_hash_commitment_number: HashMap<PaymentHash, u64>,
787 // We store two local commitment transactions to avoid any race conditions where we may update
788 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
789 // various monitors for one channel being out of sync, and us broadcasting a local
790 // transaction for which we have deleted claim information on some watchtowers.
791 prev_local_signed_commitment_tx: Option<LocalSignedTx>,
792 current_local_signed_commitment_tx: Option<LocalSignedTx>,
794 // Used just for ChannelManager to make sure it has the latest channel data during
796 current_remote_commitment_number: u64,
798 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
800 pending_htlcs_updated: Vec<HTLCUpdate>,
801 pending_events: Vec<events::Event>,
803 // Thanks to data loss protection, we may be able to claim our non-htlc funds
804 // back, this is the script we have to spend from but we need to
805 // scan every commitment transaction for that
806 to_remote_rescue: Option<(Script, SecretKey)>,
808 // Used to track onchain events, i.e transactions parts of channels confirmed on chain, on which
809 // we have to take actions once they reach enough confs. Key is a block height timer, i.e we enforce
810 // actions when we receive a block with given height. Actions depend on OnchainEvent type.
811 onchain_events_waiting_threshold_conf: HashMap<u32, Vec<OnchainEvent>>,
813 // If we get serialized out and re-read, we need to make sure that the chain monitoring
814 // interface knows about the TXOs that we want to be notified of spends of. We could probably
815 // be smart and derive them from the above storage fields, but its much simpler and more
816 // Obviously Correct (tm) if we just keep track of them explicitly.
817 outputs_to_watch: HashMap<Sha256dHash, Vec<Script>>,
820 pub onchain_tx_handler: OnchainTxHandler,
822 onchain_tx_handler: OnchainTxHandler,
824 // We simply modify last_block_hash in Channel's block_connected so that serialization is
825 // consistent but hopefully the users' copy handles block_connected in a consistent way.
826 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
827 // their last_block_hash from its state and not based on updated copies that didn't run through
828 // the full block_connected).
829 pub(crate) last_block_hash: Sha256dHash,
830 secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
834 #[cfg(any(test, feature = "fuzztarget"))]
835 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
836 /// underlying object
837 impl<ChanSigner: ChannelKeys> PartialEq for ChannelMonitor<ChanSigner> {
838 fn eq(&self, other: &Self) -> bool {
839 if self.latest_update_id != other.latest_update_id ||
840 self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
841 self.key_storage != other.key_storage ||
842 self.their_htlc_base_key != other.their_htlc_base_key ||
843 self.their_delayed_payment_base_key != other.their_delayed_payment_base_key ||
844 self.funding_redeemscript != other.funding_redeemscript ||
845 self.channel_value_satoshis != other.channel_value_satoshis ||
846 self.their_cur_revocation_points != other.their_cur_revocation_points ||
847 self.our_to_self_delay != other.our_to_self_delay ||
848 self.their_to_self_delay != other.their_to_self_delay ||
849 self.commitment_secrets != other.commitment_secrets ||
850 self.remote_claimable_outpoints != other.remote_claimable_outpoints ||
851 self.remote_commitment_txn_on_chain != other.remote_commitment_txn_on_chain ||
852 self.remote_hash_commitment_number != other.remote_hash_commitment_number ||
853 self.prev_local_signed_commitment_tx != other.prev_local_signed_commitment_tx ||
854 self.current_remote_commitment_number != other.current_remote_commitment_number ||
855 self.current_local_signed_commitment_tx != other.current_local_signed_commitment_tx ||
856 self.payment_preimages != other.payment_preimages ||
857 self.pending_htlcs_updated != other.pending_htlcs_updated ||
858 self.pending_events.len() != other.pending_events.len() || // We trust events to round-trip properly
859 self.to_remote_rescue != other.to_remote_rescue ||
860 self.onchain_events_waiting_threshold_conf != other.onchain_events_waiting_threshold_conf ||
861 self.outputs_to_watch != other.outputs_to_watch
870 impl<ChanSigner: ChannelKeys + Writeable> ChannelMonitor<ChanSigner> {
871 /// Serializes into a vec, with various modes for the exposed pub fns
872 fn write<W: Writer>(&self, writer: &mut W, for_local_storage: bool) -> Result<(), ::std::io::Error> {
873 //TODO: We still write out all the serialization here manually instead of using the fancy
874 //serialization framework we have, we should migrate things over to it.
875 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
876 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
878 self.latest_update_id.write(writer)?;
880 // Set in initial Channel-object creation, so should always be set by now:
881 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
883 match self.key_storage {
884 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 shutdown_pubkey, ref funding_info, ref current_remote_commitment_txid, ref prev_remote_commitment_txid } => {
885 writer.write_all(&[0; 1])?;
887 writer.write_all(&funding_key[..])?;
888 writer.write_all(&revocation_base_key[..])?;
889 writer.write_all(&htlc_base_key[..])?;
890 writer.write_all(&delayed_payment_base_key[..])?;
891 writer.write_all(&payment_base_key[..])?;
892 writer.write_all(&shutdown_pubkey.serialize())?;
894 &Some((ref outpoint, ref script)) => {
895 writer.write_all(&outpoint.txid[..])?;
896 writer.write_all(&byte_utils::be16_to_array(outpoint.index))?;
897 script.write(writer)?;
900 debug_assert!(false, "Try to serialize a useless Local monitor !");
903 current_remote_commitment_txid.write(writer)?;
904 prev_remote_commitment_txid.write(writer)?;
906 Storage::Watchtower { .. } => unimplemented!(),
909 writer.write_all(&self.their_htlc_base_key.as_ref().unwrap().serialize())?;
910 writer.write_all(&self.their_delayed_payment_base_key.as_ref().unwrap().serialize())?;
911 self.funding_redeemscript.as_ref().unwrap().write(writer)?;
912 self.channel_value_satoshis.unwrap().write(writer)?;
914 match self.their_cur_revocation_points {
915 Some((idx, pubkey, second_option)) => {
916 writer.write_all(&byte_utils::be48_to_array(idx))?;
917 writer.write_all(&pubkey.serialize())?;
918 match second_option {
919 Some(second_pubkey) => {
920 writer.write_all(&second_pubkey.serialize())?;
923 writer.write_all(&[0; 33])?;
928 writer.write_all(&byte_utils::be48_to_array(0))?;
932 writer.write_all(&byte_utils::be16_to_array(self.our_to_self_delay))?;
933 writer.write_all(&byte_utils::be16_to_array(self.their_to_self_delay.unwrap()))?;
935 self.commitment_secrets.write(writer)?;
937 macro_rules! serialize_htlc_in_commitment {
938 ($htlc_output: expr) => {
939 writer.write_all(&[$htlc_output.offered as u8; 1])?;
940 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
941 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
942 writer.write_all(&$htlc_output.payment_hash.0[..])?;
943 $htlc_output.transaction_output_index.write(writer)?;
947 writer.write_all(&byte_utils::be64_to_array(self.remote_claimable_outpoints.len() as u64))?;
948 for (ref txid, ref htlc_infos) in self.remote_claimable_outpoints.iter() {
949 writer.write_all(&txid[..])?;
950 writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
951 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
952 serialize_htlc_in_commitment!(htlc_output);
953 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
957 writer.write_all(&byte_utils::be64_to_array(self.remote_commitment_txn_on_chain.len() as u64))?;
958 for (ref txid, &(commitment_number, ref txouts)) in self.remote_commitment_txn_on_chain.iter() {
959 writer.write_all(&txid[..])?;
960 writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
961 (txouts.len() as u64).write(writer)?;
962 for script in txouts.iter() {
963 script.write(writer)?;
967 if for_local_storage {
968 writer.write_all(&byte_utils::be64_to_array(self.remote_hash_commitment_number.len() as u64))?;
969 for (ref payment_hash, commitment_number) in self.remote_hash_commitment_number.iter() {
970 writer.write_all(&payment_hash.0[..])?;
971 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
974 writer.write_all(&byte_utils::be64_to_array(0))?;
977 macro_rules! serialize_local_tx {
978 ($local_tx: expr) => {
979 $local_tx.tx.write(writer)?;
980 writer.write_all(&$local_tx.revocation_key.serialize())?;
981 writer.write_all(&$local_tx.a_htlc_key.serialize())?;
982 writer.write_all(&$local_tx.b_htlc_key.serialize())?;
983 writer.write_all(&$local_tx.delayed_payment_key.serialize())?;
984 writer.write_all(&$local_tx.per_commitment_point.serialize())?;
986 writer.write_all(&byte_utils::be64_to_array($local_tx.feerate_per_kw))?;
987 writer.write_all(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64))?;
988 for &(ref htlc_output, ref sig, ref htlc_source) in $local_tx.htlc_outputs.iter() {
989 serialize_htlc_in_commitment!(htlc_output);
990 if let &Some(ref their_sig) = sig {
992 writer.write_all(&their_sig.serialize_compact())?;
996 htlc_source.write(writer)?;
1001 if let Some(ref prev_local_tx) = self.prev_local_signed_commitment_tx {
1002 writer.write_all(&[1; 1])?;
1003 serialize_local_tx!(prev_local_tx);
1005 writer.write_all(&[0; 1])?;
1008 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
1009 writer.write_all(&[1; 1])?;
1010 serialize_local_tx!(cur_local_tx);
1012 writer.write_all(&[0; 1])?;
1015 if for_local_storage {
1016 writer.write_all(&byte_utils::be48_to_array(self.current_remote_commitment_number))?;
1018 writer.write_all(&byte_utils::be48_to_array(0))?;
1021 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
1022 for payment_preimage in self.payment_preimages.values() {
1023 writer.write_all(&payment_preimage.0[..])?;
1026 writer.write_all(&byte_utils::be64_to_array(self.pending_htlcs_updated.len() as u64))?;
1027 for data in self.pending_htlcs_updated.iter() {
1028 data.write(writer)?;
1031 writer.write_all(&byte_utils::be64_to_array(self.pending_events.len() as u64))?;
1032 for event in self.pending_events.iter() {
1033 event.write(writer)?;
1036 self.last_block_hash.write(writer)?;
1037 if let Some((ref to_remote_script, ref local_key)) = self.to_remote_rescue {
1038 writer.write_all(&[1; 1])?;
1039 to_remote_script.write(writer)?;
1040 local_key.write(writer)?;
1042 writer.write_all(&[0; 1])?;
1045 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_waiting_threshold_conf.len() as u64))?;
1046 for (ref target, ref events) in self.onchain_events_waiting_threshold_conf.iter() {
1047 writer.write_all(&byte_utils::be32_to_array(**target))?;
1048 writer.write_all(&byte_utils::be64_to_array(events.len() as u64))?;
1049 for ev in events.iter() {
1051 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1053 htlc_update.0.write(writer)?;
1054 htlc_update.1.write(writer)?;
1060 (self.outputs_to_watch.len() as u64).write(writer)?;
1061 for (txid, output_scripts) in self.outputs_to_watch.iter() {
1062 txid.write(writer)?;
1063 (output_scripts.len() as u64).write(writer)?;
1064 for script in output_scripts.iter() {
1065 script.write(writer)?;
1068 self.onchain_tx_handler.write(writer)?;
1073 /// Writes this monitor into the given writer, suitable for writing to disk.
1075 /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
1076 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
1077 /// the "reorg path" (ie not just starting at the same height but starting at the highest
1078 /// common block that appears on your best chain as well as on the chain which contains the
1079 /// last block hash returned) upon deserializing the object!
1080 pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
1081 self.write(writer, true)
1084 /// Encodes this monitor into the given writer, suitable for sending to a remote watchtower
1086 /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
1087 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
1088 /// the "reorg path" (ie not just starting at the same height but starting at the highest
1089 /// common block that appears on your best chain as well as on the chain which contains the
1090 /// last block hash returned) upon deserializing the object!
1091 pub fn write_for_watchtower<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
1092 self.write(writer, false)
1096 impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
1097 pub(super) fn new(keys: ChanSigner, shutdown_pubkey: &PublicKey,
1098 our_to_self_delay: u16, destination_script: &Script, funding_info: (OutPoint, Script),
1099 their_htlc_base_key: &PublicKey, their_delayed_payment_base_key: &PublicKey,
1100 their_to_self_delay: u16, funding_redeemscript: Script, channel_value_satoshis: u64,
1101 commitment_transaction_number_obscure_factor: u64,
1102 logger: Arc<Logger>) -> ChannelMonitor<ChanSigner> {
1104 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
1105 let funding_key = keys.funding_key().clone();
1106 let revocation_base_key = keys.revocation_base_key().clone();
1107 let htlc_base_key = keys.htlc_base_key().clone();
1108 let delayed_payment_base_key = keys.delayed_payment_base_key().clone();
1109 let payment_base_key = keys.payment_base_key().clone();
1111 latest_update_id: 0,
1112 commitment_transaction_number_obscure_factor,
1114 key_storage: Storage::Local {
1117 revocation_base_key,
1119 delayed_payment_base_key,
1121 shutdown_pubkey: shutdown_pubkey.clone(),
1122 funding_info: Some(funding_info),
1123 current_remote_commitment_txid: None,
1124 prev_remote_commitment_txid: None,
1126 their_htlc_base_key: Some(their_htlc_base_key.clone()),
1127 their_delayed_payment_base_key: Some(their_delayed_payment_base_key.clone()),
1128 funding_redeemscript: Some(funding_redeemscript),
1129 channel_value_satoshis: Some(channel_value_satoshis),
1130 their_cur_revocation_points: None,
1132 our_to_self_delay: our_to_self_delay,
1133 their_to_self_delay: Some(their_to_self_delay),
1135 commitment_secrets: CounterpartyCommitmentSecrets::new(),
1136 remote_claimable_outpoints: HashMap::new(),
1137 remote_commitment_txn_on_chain: HashMap::new(),
1138 remote_hash_commitment_number: HashMap::new(),
1140 prev_local_signed_commitment_tx: None,
1141 current_local_signed_commitment_tx: None,
1142 current_remote_commitment_number: 1 << 48,
1144 payment_preimages: HashMap::new(),
1145 pending_htlcs_updated: Vec::new(),
1146 pending_events: Vec::new(),
1148 to_remote_rescue: None,
1150 onchain_events_waiting_threshold_conf: HashMap::new(),
1151 outputs_to_watch: HashMap::new(),
1153 onchain_tx_handler: OnchainTxHandler::new(destination_script.clone(), logger.clone()),
1155 last_block_hash: Default::default(),
1156 secp_ctx: Secp256k1::new(),
1161 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
1162 /// needed by local commitment transactions HTCLs nor by remote ones. Unless we haven't already seen remote
1163 /// commitment transaction's secret, they are de facto pruned (we can use revocation key).
1164 pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
1165 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
1166 return Err(MonitorUpdateError("Previous secret did not match new one"));
1169 // Prune HTLCs from the previous remote commitment tx so we don't generate failure/fulfill
1170 // events for now-revoked/fulfilled HTLCs.
1171 if let Storage::Local { ref mut prev_remote_commitment_txid, .. } = self.key_storage {
1172 if let Some(txid) = prev_remote_commitment_txid.take() {
1173 for &mut (_, ref mut source) in self.remote_claimable_outpoints.get_mut(&txid).unwrap() {
1179 if !self.payment_preimages.is_empty() {
1180 let local_signed_commitment_tx = self.current_local_signed_commitment_tx.as_ref().expect("Channel needs at least an initial commitment tx !");
1181 let prev_local_signed_commitment_tx = self.prev_local_signed_commitment_tx.as_ref();
1182 let min_idx = self.get_min_seen_secret();
1183 let remote_hash_commitment_number = &mut self.remote_hash_commitment_number;
1185 self.payment_preimages.retain(|&k, _| {
1186 for &(ref htlc, _, _) in &local_signed_commitment_tx.htlc_outputs {
1187 if k == htlc.payment_hash {
1191 if let Some(prev_local_commitment_tx) = prev_local_signed_commitment_tx {
1192 for &(ref htlc, _, _) in prev_local_commitment_tx.htlc_outputs.iter() {
1193 if k == htlc.payment_hash {
1198 let contains = if let Some(cn) = remote_hash_commitment_number.get(&k) {
1205 remote_hash_commitment_number.remove(&k);
1214 /// Informs this monitor of the latest remote (ie non-broadcastable) commitment transaction.
1215 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
1216 /// possibly future revocation/preimage information) to claim outputs where possible.
1217 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
1218 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) {
1219 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
1220 // so that a remote monitor doesn't learn anything unless there is a malicious close.
1221 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
1223 for &(ref htlc, _) in &htlc_outputs {
1224 self.remote_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
1227 let new_txid = unsigned_commitment_tx.txid();
1228 log_trace!(self, "Tracking new remote commitment transaction with txid {} at commitment number {} with {} HTLC outputs", new_txid, commitment_number, htlc_outputs.len());
1229 log_trace!(self, "New potential remote commitment transaction: {}", encode::serialize_hex(unsigned_commitment_tx));
1230 if let Storage::Local { ref mut current_remote_commitment_txid, ref mut prev_remote_commitment_txid, .. } = self.key_storage {
1231 *prev_remote_commitment_txid = current_remote_commitment_txid.take();
1232 *current_remote_commitment_txid = Some(new_txid);
1234 self.remote_claimable_outpoints.insert(new_txid, htlc_outputs);
1235 self.current_remote_commitment_number = commitment_number;
1236 //TODO: Merge this into the other per-remote-transaction output storage stuff
1237 match self.their_cur_revocation_points {
1238 Some(old_points) => {
1239 if old_points.0 == commitment_number + 1 {
1240 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
1241 } else if old_points.0 == commitment_number + 2 {
1242 if let Some(old_second_point) = old_points.2 {
1243 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
1245 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1248 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1252 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1257 pub(super) fn provide_rescue_remote_commitment_tx_info(&mut self, their_revocation_point: PublicKey) {
1258 match self.key_storage {
1259 Storage::Local { ref payment_base_key, ref keys, .. } => {
1260 if let Ok(payment_key) = chan_utils::derive_public_key(&self.secp_ctx, &their_revocation_point, &keys.pubkeys().payment_basepoint) {
1261 let to_remote_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0)
1262 .push_slice(&Hash160::hash(&payment_key.serialize())[..])
1264 if let Ok(to_remote_key) = chan_utils::derive_private_key(&self.secp_ctx, &their_revocation_point, &payment_base_key) {
1265 self.to_remote_rescue = Some((to_remote_script, to_remote_key));
1269 Storage::Watchtower { .. } => {}
1273 /// Informs this monitor of the latest local (ie broadcastable) commitment transaction. The
1274 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
1275 /// is important that any clones of this channel monitor (including remote clones) by kept
1276 /// up-to-date as our local commitment transaction is updated.
1277 /// Panics if set_their_to_self_delay has never been called.
1278 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> {
1279 if self.their_to_self_delay.is_none() {
1280 return Err(MonitorUpdateError("Got a local commitment tx info update before we'd set basic information about the channel"));
1282 self.prev_local_signed_commitment_tx = self.current_local_signed_commitment_tx.take();
1283 self.current_local_signed_commitment_tx = Some(LocalSignedTx {
1284 txid: commitment_tx.txid(),
1286 revocation_key: local_keys.revocation_key,
1287 a_htlc_key: local_keys.a_htlc_key,
1288 b_htlc_key: local_keys.b_htlc_key,
1289 delayed_payment_key: local_keys.a_delayed_payment_key,
1290 per_commitment_point: local_keys.per_commitment_point,
1297 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
1298 /// commitment_tx_infos which contain the payment hash have been revoked.
1299 pub(super) fn provide_payment_preimage(&mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage) {
1300 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
1303 pub(super) fn broadcast_latest_local_commitment_txn<B: Deref>(&mut self, broadcaster: &B)
1304 where B::Target: BroadcasterInterface,
1306 for tx in self.get_latest_local_commitment_txn().iter() {
1307 broadcaster.broadcast_transaction(tx);
1311 /// Used in Channel to cheat wrt the update_ids since it plays games, will be removed soon!
1312 pub(super) fn update_monitor_ooo(&mut self, mut updates: ChannelMonitorUpdate) -> Result<(), MonitorUpdateError> {
1313 for update in updates.updates.drain(..) {
1315 ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { commitment_tx, local_keys, feerate_per_kw, htlc_outputs } =>
1316 self.provide_latest_local_commitment_tx_info(commitment_tx, local_keys, feerate_per_kw, htlc_outputs)?,
1317 ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
1318 self.provide_latest_remote_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point),
1319 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
1320 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
1321 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
1322 self.provide_secret(idx, secret)?,
1323 ChannelMonitorUpdateStep::RescueRemoteCommitmentTXInfo { their_current_per_commitment_point } =>
1324 self.provide_rescue_remote_commitment_tx_info(their_current_per_commitment_point),
1325 ChannelMonitorUpdateStep::ChannelForceClosed { .. } => {},
1328 self.latest_update_id = updates.update_id;
1332 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
1335 /// panics if the given update is not the next update by update_id.
1336 pub fn update_monitor<B: Deref>(&mut self, mut updates: ChannelMonitorUpdate, broadcaster: &B) -> Result<(), MonitorUpdateError>
1337 where B::Target: BroadcasterInterface,
1339 if self.latest_update_id + 1 != updates.update_id {
1340 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
1342 for update in updates.updates.drain(..) {
1344 ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo { commitment_tx, local_keys, feerate_per_kw, htlc_outputs } =>
1345 self.provide_latest_local_commitment_tx_info(commitment_tx, local_keys, feerate_per_kw, htlc_outputs)?,
1346 ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo { unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point } =>
1347 self.provide_latest_remote_commitment_tx_info(&unsigned_commitment_tx, htlc_outputs, commitment_number, their_revocation_point),
1348 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } =>
1349 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage),
1350 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } =>
1351 self.provide_secret(idx, secret)?,
1352 ChannelMonitorUpdateStep::RescueRemoteCommitmentTXInfo { their_current_per_commitment_point } =>
1353 self.provide_rescue_remote_commitment_tx_info(their_current_per_commitment_point),
1354 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
1355 if should_broadcast {
1356 self.broadcast_latest_local_commitment_txn(broadcaster);
1358 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");
1363 self.latest_update_id = updates.update_id;
1367 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
1369 pub fn get_latest_update_id(&self) -> u64 {
1370 self.latest_update_id
1373 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
1374 pub fn get_funding_txo(&self) -> Option<OutPoint> {
1375 match self.key_storage {
1376 Storage::Local { ref funding_info, .. } => {
1377 match funding_info {
1378 &Some((outpoint, _)) => Some(outpoint),
1382 Storage::Watchtower { .. } => {
1388 /// Gets a list of txids, with their output scripts (in the order they appear in the
1389 /// transaction), which we must learn about spends of via block_connected().
1390 pub fn get_outputs_to_watch(&self) -> &HashMap<Sha256dHash, Vec<Script>> {
1391 &self.outputs_to_watch
1394 /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
1395 /// Generally useful when deserializing as during normal operation the return values of
1396 /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
1397 /// that the get_funding_txo outpoint and transaction must also be monitored for!).
1398 pub fn get_monitored_outpoints(&self) -> Vec<(Sha256dHash, u32, &Script)> {
1399 let mut res = Vec::with_capacity(self.remote_commitment_txn_on_chain.len() * 2);
1400 for (ref txid, &(_, ref outputs)) in self.remote_commitment_txn_on_chain.iter() {
1401 for (idx, output) in outputs.iter().enumerate() {
1402 res.push(((*txid).clone(), idx as u32, output));
1408 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1409 /// ChannelManager via ManyChannelMonitor::get_and_clear_pending_htlcs_updated().
1410 pub fn get_and_clear_pending_htlcs_updated(&mut self) -> Vec<HTLCUpdate> {
1411 let mut ret = Vec::new();
1412 mem::swap(&mut ret, &mut self.pending_htlcs_updated);
1416 /// Gets the list of pending events which were generated by previous actions, clearing the list
1419 /// This is called by ManyChannelMonitor::get_and_clear_pending_events() and is equivalent to
1420 /// EventsProvider::get_and_clear_pending_events() except that it requires &mut self as we do
1421 /// no internal locking in ChannelMonitors.
1422 pub fn get_and_clear_pending_events(&mut self) -> Vec<events::Event> {
1423 let mut ret = Vec::new();
1424 mem::swap(&mut ret, &mut self.pending_events);
1428 /// Can only fail if idx is < get_min_seen_secret
1429 pub(super) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
1430 self.commitment_secrets.get_secret(idx)
1433 pub(super) fn get_min_seen_secret(&self) -> u64 {
1434 self.commitment_secrets.get_min_seen_secret()
1437 pub(super) fn get_cur_remote_commitment_number(&self) -> u64 {
1438 self.current_remote_commitment_number
1441 pub(super) fn get_cur_local_commitment_number(&self) -> u64 {
1442 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1443 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)
1444 } else { 0xffff_ffff_ffff }
1447 /// Attempts to claim a remote commitment transaction's outputs using the revocation key and
1448 /// data in remote_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
1449 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
1450 /// HTLC-Success/HTLC-Timeout transactions.
1451 /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
1452 /// revoked remote commitment tx
1453 fn check_spend_remote_transaction(&mut self, tx: &Transaction, height: u32) -> (Vec<ClaimRequest>, (Sha256dHash, Vec<TxOut>), Vec<SpendableOutputDescriptor>) {
1454 // Most secp and related errors trying to create keys means we have no hope of constructing
1455 // a spend transaction...so we return no transactions to broadcast
1456 let mut claimable_outpoints = Vec::new();
1457 let mut watch_outputs = Vec::new();
1458 let mut spendable_outputs = Vec::new();
1460 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1461 let per_commitment_option = self.remote_claimable_outpoints.get(&commitment_txid);
1463 macro_rules! ignore_error {
1464 ( $thing : expr ) => {
1467 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs), spendable_outputs)
1472 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);
1473 if commitment_number >= self.get_min_seen_secret() {
1474 let secret = self.get_secret(commitment_number).unwrap();
1475 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1476 let (revocation_pubkey, revocation_key, b_htlc_key, local_payment_key) = match self.key_storage {
1477 Storage::Local { ref keys, ref revocation_base_key, ref payment_base_key, .. } => {
1478 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1479 (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &keys.pubkeys().revocation_basepoint)),
1480 ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, &revocation_base_key)),
1481 ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &keys.pubkeys().htlc_basepoint)),
1482 Some(ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, &per_commitment_point, &payment_base_key))))
1484 Storage::Watchtower { .. } => {
1488 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()));
1489 let a_htlc_key = match self.their_htlc_base_key {
1490 None => return (claimable_outpoints, (commitment_txid, watch_outputs), spendable_outputs),
1491 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)),
1494 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.our_to_self_delay, &delayed_key);
1495 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1497 let local_payment_p2wpkh = if let Some(payment_key) = local_payment_key {
1498 // Note that the Network here is ignored as we immediately drop the address for the
1499 // script_pubkey version.
1500 let payment_hash160 = Hash160::hash(&PublicKey::from_secret_key(&self.secp_ctx, &payment_key).serialize());
1501 Some(Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_hash160[..]).into_script())
1504 // First, process non-htlc outputs (to_local & to_remote)
1505 for (idx, outp) in tx.output.iter().enumerate() {
1506 if outp.script_pubkey == revokeable_p2wsh {
1507 let witness_data = InputMaterial::Revoked { witness_script: revokeable_redeemscript.clone(), pubkey: Some(revocation_pubkey), key: revocation_key, is_htlc: false, amount: outp.value };
1508 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});
1509 } else if Some(&outp.script_pubkey) == local_payment_p2wpkh.as_ref() {
1510 spendable_outputs.push(SpendableOutputDescriptor::DynamicOutputP2WPKH {
1511 outpoint: BitcoinOutPoint { txid: commitment_txid, vout: idx as u32 },
1512 key: local_payment_key.unwrap(),
1513 output: outp.clone(),
1518 // Then, try to find revoked htlc outputs
1519 if let Some(ref per_commitment_data) = per_commitment_option {
1520 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1521 if let Some(transaction_output_index) = htlc.transaction_output_index {
1522 let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1523 if transaction_output_index as usize >= tx.output.len() ||
1524 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
1525 tx.output[transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
1526 return (claimable_outpoints, (commitment_txid, watch_outputs), spendable_outputs); // Corrupted per_commitment_data, fuck this user
1528 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 };
1529 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable: true, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1534 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
1535 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
1536 // We're definitely a remote commitment transaction!
1537 log_trace!(self, "Got broadcast of revoked remote commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
1538 watch_outputs.append(&mut tx.output.clone());
1539 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1541 macro_rules! check_htlc_fails {
1542 ($txid: expr, $commitment_tx: expr) => {
1543 if let Some(ref outpoints) = self.remote_claimable_outpoints.get($txid) {
1544 for &(ref htlc, ref source_option) in outpoints.iter() {
1545 if let &Some(ref source) = source_option {
1546 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);
1547 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1548 hash_map::Entry::Occupied(mut entry) => {
1549 let e = entry.get_mut();
1550 e.retain(|ref event| {
1552 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1553 return htlc_update.0 != **source
1557 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1559 hash_map::Entry::Vacant(entry) => {
1560 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1568 if let Storage::Local { ref current_remote_commitment_txid, ref prev_remote_commitment_txid, .. } = self.key_storage {
1569 if let &Some(ref txid) = current_remote_commitment_txid {
1570 check_htlc_fails!(txid, "current");
1572 if let &Some(ref txid) = prev_remote_commitment_txid {
1573 check_htlc_fails!(txid, "remote");
1576 // No need to check local commitment txn, symmetric HTLCSource must be present as per-htlc data on remote commitment tx
1578 } else if let Some(per_commitment_data) = per_commitment_option {
1579 // While this isn't useful yet, there is a potential race where if a counterparty
1580 // revokes a state at the same time as the commitment transaction for that state is
1581 // confirmed, and the watchtower receives the block before the user, the user could
1582 // upload a new ChannelMonitor with the revocation secret but the watchtower has
1583 // already processed the block, resulting in the remote_commitment_txn_on_chain entry
1584 // not being generated by the above conditional. Thus, to be safe, we go ahead and
1586 watch_outputs.append(&mut tx.output.clone());
1587 self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
1589 log_trace!(self, "Got broadcast of non-revoked remote commitment transaction {}", commitment_txid);
1591 macro_rules! check_htlc_fails {
1592 ($txid: expr, $commitment_tx: expr, $id: tt) => {
1593 if let Some(ref latest_outpoints) = self.remote_claimable_outpoints.get($txid) {
1594 $id: for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1595 if let &Some(ref source) = source_option {
1596 // Check if the HTLC is present in the commitment transaction that was
1597 // broadcast, but not if it was below the dust limit, which we should
1598 // fail backwards immediately as there is no way for us to learn the
1599 // payment_preimage.
1600 // Note that if the dust limit were allowed to change between
1601 // commitment transactions we'd want to be check whether *any*
1602 // broadcastable commitment transaction has the HTLC in it, but it
1603 // cannot currently change after channel initialization, so we don't
1605 for &(ref broadcast_htlc, ref broadcast_source) in per_commitment_data.iter() {
1606 if broadcast_htlc.transaction_output_index.is_some() && Some(source) == broadcast_source.as_ref() {
1610 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);
1611 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
1612 hash_map::Entry::Occupied(mut entry) => {
1613 let e = entry.get_mut();
1614 e.retain(|ref event| {
1616 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1617 return htlc_update.0 != **source
1621 e.push(OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())});
1623 hash_map::Entry::Vacant(entry) => {
1624 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ((**source).clone(), htlc.payment_hash.clone())}]);
1632 if let Storage::Local { ref current_remote_commitment_txid, ref prev_remote_commitment_txid, .. } = self.key_storage {
1633 if let &Some(ref txid) = current_remote_commitment_txid {
1634 check_htlc_fails!(txid, "current", 'current_loop);
1636 if let &Some(ref txid) = prev_remote_commitment_txid {
1637 check_htlc_fails!(txid, "previous", 'prev_loop);
1641 if let Some(revocation_points) = self.their_cur_revocation_points {
1642 let revocation_point_option =
1643 if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1644 else if let Some(point) = revocation_points.2.as_ref() {
1645 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1647 if let Some(revocation_point) = revocation_point_option {
1648 let (revocation_pubkey, b_htlc_key, htlc_privkey) = match self.key_storage {
1649 Storage::Local { ref keys, ref htlc_base_key, .. } => {
1650 (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &keys.pubkeys().revocation_basepoint)),
1651 ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &keys.pubkeys().htlc_basepoint)),
1652 ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, revocation_point, &htlc_base_key)))
1654 Storage::Watchtower { .. } => { unimplemented!() }
1656 let a_htlc_key = match self.their_htlc_base_key {
1657 None => return (claimable_outpoints, (commitment_txid, watch_outputs), spendable_outputs),
1658 Some(their_htlc_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &their_htlc_base_key)),
1661 // First, mark as spendable our to_remote output
1662 for (idx, outp) in tx.output.iter().enumerate() {
1663 if outp.script_pubkey.is_v0_p2wpkh() {
1664 match self.key_storage {
1665 Storage::Local { ref payment_base_key, .. } => {
1666 if let Ok(local_key) = chan_utils::derive_private_key(&self.secp_ctx, &revocation_point, &payment_base_key) {
1667 spendable_outputs.push(SpendableOutputDescriptor::DynamicOutputP2WPKH {
1668 outpoint: BitcoinOutPoint { txid: commitment_txid, vout: idx as u32 },
1670 output: outp.clone(),
1674 Storage::Watchtower { .. } => {}
1676 break; // Only to_remote ouput is claimable
1680 // Then, try to find htlc outputs
1681 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1682 if let Some(transaction_output_index) = htlc.transaction_output_index {
1683 let expected_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
1684 if transaction_output_index as usize >= tx.output.len() ||
1685 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 ||
1686 tx.output[transaction_output_index as usize].script_pubkey != expected_script.to_v0_p2wsh() {
1687 return (claimable_outpoints, (commitment_txid, watch_outputs), spendable_outputs); // Corrupted per_commitment_data, fuck this user
1689 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
1690 let aggregable = if !htlc.offered { false } else { true };
1691 if preimage.is_some() || !htlc.offered {
1692 let witness_data = InputMaterial::RemoteHTLC { witness_script: expected_script, key: htlc_privkey, preimage, amount: htlc.amount_msat / 1000, locktime: htlc.cltv_expiry };
1693 claimable_outpoints.push(ClaimRequest { absolute_timelock: htlc.cltv_expiry, aggregable, outpoint: BitcoinOutPoint { txid: commitment_txid, vout: transaction_output_index }, witness_data });
1699 } else if let Some((ref to_remote_rescue, ref local_key)) = self.to_remote_rescue {
1700 for (idx, outp) in tx.output.iter().enumerate() {
1701 if to_remote_rescue == &outp.script_pubkey {
1702 spendable_outputs.push(SpendableOutputDescriptor::DynamicOutputP2WPKH {
1703 outpoint: BitcoinOutPoint { txid: commitment_txid, vout: idx as u32 },
1704 key: local_key.clone(),
1705 output: outp.clone(),
1710 (claimable_outpoints, (commitment_txid, watch_outputs), spendable_outputs)
1713 /// Attempts to claim a remote HTLC-Success/HTLC-Timeout's outputs using the revocation key
1714 fn check_spend_remote_htlc(&mut self, tx: &Transaction, commitment_number: u64, height: u32) -> (Vec<ClaimRequest>, Option<(Sha256dHash, Vec<TxOut>)>) {
1715 let htlc_txid = tx.txid();
1716 if tx.input.len() != 1 || tx.output.len() != 1 || tx.input[0].witness.len() != 5 {
1717 return (Vec::new(), None)
1720 macro_rules! ignore_error {
1721 ( $thing : expr ) => {
1724 Err(_) => return (Vec::new(), None)
1729 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
1730 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1731 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1732 let (revocation_pubkey, revocation_key) = match self.key_storage {
1733 Storage::Local { ref keys, ref revocation_base_key, .. } => {
1734 (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &keys.pubkeys().revocation_basepoint)),
1735 ignore_error!(chan_utils::derive_private_revocation_key(&self.secp_ctx, &per_commitment_key, revocation_base_key)))
1737 Storage::Watchtower { .. } => { unimplemented!() }
1739 let delayed_key = match self.their_delayed_payment_base_key {
1740 None => return (Vec::new(), None),
1741 Some(their_delayed_payment_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &their_delayed_payment_base_key)),
1743 let redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.our_to_self_delay, &delayed_key);
1745 log_trace!(self, "Remote HTLC broadcast {}:{}", htlc_txid, 0);
1746 let witness_data = InputMaterial::Revoked { witness_script: redeemscript, pubkey: Some(revocation_pubkey), key: revocation_key, is_htlc: false, amount: tx.output[0].value };
1747 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 });
1748 (claimable_outpoints, Some((htlc_txid, tx.output.clone())))
1751 fn broadcast_by_local_state(&self, local_tx: &LocalSignedTx, delayed_payment_base_key: &SecretKey) -> (Vec<Transaction>, Vec<SpendableOutputDescriptor>, Vec<TxOut>) {
1752 let mut res = Vec::with_capacity(local_tx.htlc_outputs.len());
1753 let mut spendable_outputs = Vec::with_capacity(local_tx.htlc_outputs.len());
1754 let mut watch_outputs = Vec::with_capacity(local_tx.htlc_outputs.len());
1756 macro_rules! add_dynamic_output {
1757 ($father_tx: expr, $vout: expr) => {
1758 if let Ok(local_delayedkey) = chan_utils::derive_private_key(&self.secp_ctx, &local_tx.per_commitment_point, delayed_payment_base_key) {
1759 spendable_outputs.push(SpendableOutputDescriptor::DynamicOutputP2WSH {
1760 outpoint: BitcoinOutPoint { txid: $father_tx.txid(), vout: $vout },
1761 key: local_delayedkey,
1762 witness_script: chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.our_to_self_delay, &local_tx.delayed_payment_key),
1763 to_self_delay: self.our_to_self_delay,
1764 output: $father_tx.output[$vout as usize].clone(),
1770 let redeemscript = chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.their_to_self_delay.unwrap(), &local_tx.delayed_payment_key);
1771 let revokeable_p2wsh = redeemscript.to_v0_p2wsh();
1772 for (idx, output) in local_tx.tx.without_valid_witness().output.iter().enumerate() {
1773 if output.script_pubkey == revokeable_p2wsh {
1774 add_dynamic_output!(local_tx.tx.without_valid_witness(), idx as u32);
1779 if let &Storage::Local { ref htlc_base_key, .. } = &self.key_storage {
1780 for &(ref htlc, ref sigs, _) in local_tx.htlc_outputs.iter() {
1781 if let Some(transaction_output_index) = htlc.transaction_output_index {
1782 if let &Some(ref their_sig) = sigs {
1784 log_trace!(self, "Broadcasting HTLC-Timeout transaction against local commitment transactions");
1785 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);
1786 let (our_sig, htlc_script) = match
1787 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) {
1792 add_dynamic_output!(htlc_timeout_tx, 0);
1793 let mut per_input_material = HashMap::with_capacity(1);
1794 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});
1795 //TODO: with option_simplified_commitment track outpoint too
1796 log_trace!(self, "Outpoint {}:{} is being being claimed", htlc_timeout_tx.input[0].previous_output.vout, htlc_timeout_tx.input[0].previous_output.txid);
1797 res.push(htlc_timeout_tx);
1799 if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1800 log_trace!(self, "Broadcasting HTLC-Success transaction against local commitment transactions");
1801 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);
1802 let (our_sig, htlc_script) = match
1803 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) {
1808 add_dynamic_output!(htlc_success_tx, 0);
1809 let mut per_input_material = HashMap::with_capacity(1);
1810 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});
1811 //TODO: with option_simplified_commitment track outpoint too
1812 log_trace!(self, "Outpoint {}:{} is being being claimed", htlc_success_tx.input[0].previous_output.vout, htlc_success_tx.input[0].previous_output.txid);
1813 res.push(htlc_success_tx);
1816 watch_outputs.push(local_tx.tx.without_valid_witness().output[transaction_output_index as usize].clone());
1817 } else { panic!("Should have sigs for non-dust local tx outputs!") }
1822 (res, spendable_outputs, watch_outputs)
1825 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
1826 /// revoked using data in local_claimable_outpoints.
1827 /// Should not be used if check_spend_revoked_transaction succeeds.
1828 fn check_spend_local_transaction(&mut self, tx: &Transaction, height: u32) -> (Vec<Transaction>, Vec<SpendableOutputDescriptor>, (Sha256dHash, Vec<TxOut>)) {
1829 let commitment_txid = tx.txid();
1830 let mut local_txn = Vec::new();
1831 let mut spendable_outputs = Vec::new();
1832 let mut watch_outputs = Vec::new();
1834 macro_rules! wait_threshold_conf {
1835 ($height: expr, $source: expr, $commitment_tx: expr, $payment_hash: expr) => {
1836 log_trace!(self, "Failing HTLC with payment_hash {} from {} local commitment tx due to broadcast of transaction, waiting confirmation (at height{})", log_bytes!($payment_hash.0), $commitment_tx, height + ANTI_REORG_DELAY - 1);
1837 match self.onchain_events_waiting_threshold_conf.entry($height + ANTI_REORG_DELAY - 1) {
1838 hash_map::Entry::Occupied(mut entry) => {
1839 let e = entry.get_mut();
1840 e.retain(|ref event| {
1842 OnchainEvent::HTLCUpdate { ref htlc_update } => {
1843 return htlc_update.0 != $source
1847 e.push(OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)});
1849 hash_map::Entry::Vacant(entry) => {
1850 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: ($source, $payment_hash)}]);
1856 macro_rules! append_onchain_update {
1857 ($updates: expr) => {
1858 local_txn.append(&mut $updates.0);
1859 spendable_outputs.append(&mut $updates.1);
1860 watch_outputs.append(&mut $updates.2);
1864 // HTLCs set may differ between last and previous local commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
1865 let mut is_local_tx = false;
1867 if let &mut Some(ref mut local_tx) = &mut self.current_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.current_local_signed_commitment_tx {
1878 if local_tx.txid == commitment_txid {
1880 log_trace!(self, "Got latest 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 { .. } => { }
1891 if let &mut Some(ref mut local_tx) = &mut self.prev_local_signed_commitment_tx {
1892 if local_tx.txid == commitment_txid {
1893 match self.key_storage {
1894 Storage::Local { ref funding_key, .. } => {
1895 local_tx.tx.add_local_sig(funding_key, self.funding_redeemscript.as_ref().unwrap(), self.channel_value_satoshis.unwrap(), &self.secp_ctx);
1901 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1902 if local_tx.txid == commitment_txid {
1904 log_trace!(self, "Got previous local commitment tx broadcast, searching for available HTLCs to claim");
1905 assert!(local_tx.tx.has_local_sig());
1906 match self.key_storage {
1907 Storage::Local { ref delayed_payment_base_key, .. } => {
1908 let mut res = self.broadcast_by_local_state(local_tx, delayed_payment_base_key);
1909 append_onchain_update!(res);
1911 Storage::Watchtower { .. } => { }
1916 macro_rules! fail_dust_htlcs_after_threshold_conf {
1917 ($local_tx: expr) => {
1918 for &(ref htlc, _, ref source) in &$local_tx.htlc_outputs {
1919 if htlc.transaction_output_index.is_none() {
1920 if let &Some(ref source) = source {
1921 wait_threshold_conf!(height, source.clone(), "lastest", htlc.payment_hash.clone());
1929 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1930 fail_dust_htlcs_after_threshold_conf!(local_tx);
1932 if let &Some(ref local_tx) = &self.prev_local_signed_commitment_tx {
1933 fail_dust_htlcs_after_threshold_conf!(local_tx);
1937 (local_txn, spendable_outputs, (commitment_txid, watch_outputs))
1940 /// Generate a spendable output event when closing_transaction get registered onchain.
1941 fn check_spend_closing_transaction(&self, tx: &Transaction) -> Option<SpendableOutputDescriptor> {
1942 if tx.input[0].sequence == 0xFFFFFFFF && !tx.input[0].witness.is_empty() && tx.input[0].witness.last().unwrap().len() == 71 {
1943 match self.key_storage {
1944 Storage::Local { ref shutdown_pubkey, .. } => {
1945 let our_channel_close_key_hash = Hash160::hash(&shutdown_pubkey.serialize());
1946 let shutdown_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_close_key_hash[..]).into_script();
1947 for (idx, output) in tx.output.iter().enumerate() {
1948 if shutdown_script == output.script_pubkey {
1949 return Some(SpendableOutputDescriptor::StaticOutput {
1950 outpoint: BitcoinOutPoint { txid: tx.txid(), vout: idx as u32 },
1951 output: output.clone(),
1956 Storage::Watchtower { .. } => {
1957 //TODO: we need to ensure an offline client will generate the event when it
1958 // comes back online after only the watchtower saw the transaction
1965 /// Used by ChannelManager deserialization to broadcast the latest local state if its copy of
1966 /// the Channel was out-of-date. You may use it to get a broadcastable local toxic tx in case of
1967 /// fallen-behind, i.e when receiving a channel_reestablish with a proof that our remote side knows
1968 /// a higher revocation secret than the local commitment number we are aware of. Broadcasting these
1969 /// transactions are UNSAFE, as they allow remote side to punish you. Nevertheless you may want to
1970 /// broadcast them if remote don't close channel with his higher commitment transaction after a
1971 /// substantial amount of time (a month or even a year) to get back funds. Best may be to contact
1972 /// out-of-band the other node operator to coordinate with him if option is available to you.
1973 /// In any-case, choice is up to the user.
1974 pub fn get_latest_local_commitment_txn(&mut self) -> Vec<Transaction> {
1975 // TODO: We should likely move all of the logic in here into OnChainTxHandler and unify it
1976 // to ensure add_local_sig is only ever called once no matter what. This likely includes
1977 // tracking state and panic!()ing if we get an update after force-closure/local-tx signing.
1978 log_trace!(self, "Getting signed latest local commitment transaction!");
1979 if let &mut Some(ref mut local_tx) = &mut self.current_local_signed_commitment_tx {
1980 match self.key_storage {
1981 Storage::Local { ref funding_key, .. } => {
1982 local_tx.tx.add_local_sig(funding_key, self.funding_redeemscript.as_ref().unwrap(), self.channel_value_satoshis.unwrap(), &self.secp_ctx);
1987 if let &Some(ref local_tx) = &self.current_local_signed_commitment_tx {
1988 let mut res = vec![local_tx.tx.with_valid_witness().clone()];
1989 match self.key_storage {
1990 Storage::Local { ref delayed_payment_base_key, .. } => {
1991 res.append(&mut self.broadcast_by_local_state(local_tx, delayed_payment_base_key).0);
1992 // 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.
1993 // The data will be re-generated and tracked in check_spend_local_transaction if we get a confirmation.
1995 _ => panic!("Can only broadcast by local channelmonitor"),
2003 /// Called by SimpleManyChannelMonitor::block_connected, which implements
2004 /// ChainListener::block_connected.
2005 /// Eventually this should be pub and, roughly, implement ChainListener, however this requires
2006 /// &mut self, as well as returns new spendable outputs and outpoints to watch for spending of
2008 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>)>
2009 where B::Target: BroadcasterInterface,
2010 F::Target: FeeEstimator
2012 for tx in txn_matched {
2013 let mut output_val = 0;
2014 for out in tx.output.iter() {
2015 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
2016 output_val += out.value;
2017 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
2021 log_trace!(self, "Block {} at height {} connected with {} txn matched", block_hash, height, txn_matched.len());
2022 let mut watch_outputs = Vec::new();
2023 let mut spendable_outputs = Vec::new();
2024 let mut claimable_outpoints = Vec::new();
2025 for tx in txn_matched {
2026 if tx.input.len() == 1 {
2027 // Assuming our keys were not leaked (in which case we're screwed no matter what),
2028 // commitment transactions and HTLC transactions will all only ever have one input,
2029 // which is an easy way to filter out any potential non-matching txn for lazy
2031 let prevout = &tx.input[0].previous_output;
2032 let funding_txo = match self.key_storage {
2033 Storage::Local { ref funding_info, .. } => {
2034 funding_info.clone()
2036 Storage::Watchtower { .. } => {
2040 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) {
2041 if (tx.input[0].sequence >> 8*3) as u8 == 0x80 && (tx.lock_time >> 8*3) as u8 == 0x20 {
2042 let (mut new_outpoints, new_outputs, mut spendable_output) = self.check_spend_remote_transaction(&tx, height);
2043 spendable_outputs.append(&mut spendable_output);
2044 if !new_outputs.1.is_empty() {
2045 watch_outputs.push(new_outputs);
2047 if new_outpoints.is_empty() {
2048 let (local_txn, mut spendable_output, new_outputs) = self.check_spend_local_transaction(&tx, height);
2049 spendable_outputs.append(&mut spendable_output);
2050 for tx in local_txn.iter() {
2051 log_trace!(self, "Broadcast onchain {}", log_tx!(tx));
2052 broadcaster.broadcast_transaction(tx);
2054 if !new_outputs.1.is_empty() {
2055 watch_outputs.push(new_outputs);
2058 claimable_outpoints.append(&mut new_outpoints);
2060 if !funding_txo.is_none() && claimable_outpoints.is_empty() {
2061 if let Some(spendable_output) = self.check_spend_closing_transaction(&tx) {
2062 spendable_outputs.push(spendable_output);
2066 if let Some(&(commitment_number, _)) = self.remote_commitment_txn_on_chain.get(&prevout.txid) {
2067 let (mut new_outpoints, new_outputs_option) = self.check_spend_remote_htlc(&tx, commitment_number, height);
2068 claimable_outpoints.append(&mut new_outpoints);
2069 if let Some(new_outputs) = new_outputs_option {
2070 watch_outputs.push(new_outputs);
2075 // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
2076 // can also be resolved in a few other ways which can have more than one output. Thus,
2077 // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
2078 self.is_resolving_htlc_output(&tx, height);
2080 let should_broadcast = if let Some(_) = self.current_local_signed_commitment_tx {
2081 self.would_broadcast_at_height(height)
2083 if let Some(ref mut cur_local_tx) = self.current_local_signed_commitment_tx {
2084 if should_broadcast {
2085 match self.key_storage {
2086 Storage::Local { ref funding_key, .. } => {
2087 cur_local_tx.tx.add_local_sig(funding_key, self.funding_redeemscript.as_ref().unwrap(), self.channel_value_satoshis.unwrap(), &self.secp_ctx);
2093 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
2094 if should_broadcast {
2095 log_trace!(self, "Broadcast onchain {}", log_tx!(cur_local_tx.tx.with_valid_witness()));
2096 broadcaster.broadcast_transaction(&cur_local_tx.tx.with_valid_witness());
2097 match self.key_storage {
2098 Storage::Local { ref delayed_payment_base_key, .. } => {
2099 let (txs, mut spendable_output, new_outputs) = self.broadcast_by_local_state(&cur_local_tx, delayed_payment_base_key);
2100 spendable_outputs.append(&mut spendable_output);
2101 if !new_outputs.is_empty() {
2102 watch_outputs.push((cur_local_tx.txid.clone(), new_outputs));
2105 log_trace!(self, "Broadcast onchain {}", log_tx!(tx));
2106 broadcaster.broadcast_transaction(&tx);
2109 Storage::Watchtower { .. } => { },
2113 if let Some(events) = self.onchain_events_waiting_threshold_conf.remove(&height) {
2116 OnchainEvent::HTLCUpdate { htlc_update } => {
2117 log_trace!(self, "HTLC {} failure update has got enough confirmations to be passed upstream", log_bytes!((htlc_update.1).0));
2118 self.pending_htlcs_updated.push(HTLCUpdate {
2119 payment_hash: htlc_update.1,
2120 payment_preimage: None,
2121 source: htlc_update.0,
2127 let mut spendable_output = self.onchain_tx_handler.block_connected(txn_matched, claimable_outpoints, height, &*broadcaster, &*fee_estimator);
2128 spendable_outputs.append(&mut spendable_output);
2130 self.last_block_hash = block_hash.clone();
2131 for &(ref txid, ref output_scripts) in watch_outputs.iter() {
2132 self.outputs_to_watch.insert(txid.clone(), output_scripts.iter().map(|o| o.script_pubkey.clone()).collect());
2135 if spendable_outputs.len() > 0 {
2136 self.pending_events.push(events::Event::SpendableOutputs {
2137 outputs: spendable_outputs,
2144 fn block_disconnected<B: Deref, F: Deref>(&mut self, height: u32, block_hash: &Sha256dHash, broadcaster: B, fee_estimator: F)
2145 where B::Target: BroadcasterInterface,
2146 F::Target: FeeEstimator
2148 log_trace!(self, "Block {} at height {} disconnected", block_hash, height);
2149 if let Some(_) = self.onchain_events_waiting_threshold_conf.remove(&(height + ANTI_REORG_DELAY - 1)) {
2151 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
2154 self.onchain_tx_handler.block_disconnected(height, broadcaster, fee_estimator);
2156 self.last_block_hash = block_hash.clone();
2159 pub(super) fn would_broadcast_at_height(&self, height: u32) -> bool {
2160 // We need to consider all HTLCs which are:
2161 // * in any unrevoked remote commitment transaction, as they could broadcast said
2162 // transactions and we'd end up in a race, or
2163 // * are in our latest local commitment transaction, as this is the thing we will
2164 // broadcast if we go on-chain.
2165 // Note that we consider HTLCs which were below dust threshold here - while they don't
2166 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
2167 // to the source, and if we don't fail the channel we will have to ensure that the next
2168 // updates that peer sends us are update_fails, failing the channel if not. It's probably
2169 // easier to just fail the channel as this case should be rare enough anyway.
2170 macro_rules! scan_commitment {
2171 ($htlcs: expr, $local_tx: expr) => {
2172 for ref htlc in $htlcs {
2173 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
2174 // chain with enough room to claim the HTLC without our counterparty being able to
2175 // time out the HTLC first.
2176 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
2177 // concern is being able to claim the corresponding inbound HTLC (on another
2178 // channel) before it expires. In fact, we don't even really care if our
2179 // counterparty here claims such an outbound HTLC after it expired as long as we
2180 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
2181 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
2182 // we give ourselves a few blocks of headroom after expiration before going
2183 // on-chain for an expired HTLC.
2184 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
2185 // from us until we've reached the point where we go on-chain with the
2186 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
2187 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
2188 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
2189 // inbound_cltv == height + CLTV_CLAIM_BUFFER
2190 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
2191 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
2192 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
2193 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
2194 // The final, above, condition is checked for statically in channelmanager
2195 // with CHECK_CLTV_EXPIRY_SANITY_2.
2196 let htlc_outbound = $local_tx == htlc.offered;
2197 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
2198 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
2199 log_info!(self, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
2206 if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
2207 scan_commitment!(cur_local_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
2210 if let Storage::Local { ref current_remote_commitment_txid, ref prev_remote_commitment_txid, .. } = self.key_storage {
2211 if let &Some(ref txid) = current_remote_commitment_txid {
2212 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(txid) {
2213 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2216 if let &Some(ref txid) = prev_remote_commitment_txid {
2217 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(txid) {
2218 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2226 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a local
2227 /// or remote commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
2228 fn is_resolving_htlc_output(&mut self, tx: &Transaction, height: u32) {
2229 'outer_loop: for input in &tx.input {
2230 let mut payment_data = None;
2231 let revocation_sig_claim = (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && input.witness[1].len() == 33)
2232 || (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && input.witness[1].len() == 33);
2233 let accepted_preimage_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::AcceptedHTLC);
2234 let offered_preimage_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC);
2236 macro_rules! log_claim {
2237 ($tx_info: expr, $local_tx: expr, $htlc: expr, $source_avail: expr) => {
2238 // We found the output in question, but aren't failing it backwards
2239 // as we have no corresponding source and no valid remote commitment txid
2240 // to try a weak source binding with same-hash, same-value still-valid offered HTLC.
2241 // This implies either it is an inbound HTLC or an outbound HTLC on a revoked transaction.
2242 let outbound_htlc = $local_tx == $htlc.offered;
2243 if ($local_tx && revocation_sig_claim) ||
2244 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
2245 log_error!(self, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
2246 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2247 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2248 if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back" });
2250 log_info!(self, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
2251 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2252 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2253 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
2258 macro_rules! check_htlc_valid_remote {
2259 ($remote_txid: expr, $htlc_output: expr) => {
2260 if let &Some(txid) = $remote_txid {
2261 for &(ref pending_htlc, ref pending_source) in self.remote_claimable_outpoints.get(&txid).unwrap() {
2262 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
2263 if let &Some(ref source) = pending_source {
2264 log_claim!("revoked remote commitment tx", false, pending_htlc, true);
2265 payment_data = Some(((**source).clone(), $htlc_output.payment_hash));
2274 macro_rules! scan_commitment {
2275 ($htlcs: expr, $tx_info: expr, $local_tx: expr) => {
2276 for (ref htlc_output, source_option) in $htlcs {
2277 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
2278 if let Some(ref source) = source_option {
2279 log_claim!($tx_info, $local_tx, htlc_output, true);
2280 // We have a resolution of an HTLC either from one of our latest
2281 // local commitment transactions or an unrevoked remote commitment
2282 // transaction. This implies we either learned a preimage, the HTLC
2283 // has timed out, or we screwed up. In any case, we should now
2284 // resolve the source HTLC with the original sender.
2285 payment_data = Some(((*source).clone(), htlc_output.payment_hash));
2286 } else if !$local_tx {
2287 if let Storage::Local { ref current_remote_commitment_txid, .. } = self.key_storage {
2288 check_htlc_valid_remote!(current_remote_commitment_txid, htlc_output);
2290 if payment_data.is_none() {
2291 if let Storage::Local { ref prev_remote_commitment_txid, .. } = self.key_storage {
2292 check_htlc_valid_remote!(prev_remote_commitment_txid, htlc_output);
2296 if payment_data.is_none() {
2297 log_claim!($tx_info, $local_tx, htlc_output, false);
2298 continue 'outer_loop;
2305 if let Some(ref current_local_signed_commitment_tx) = self.current_local_signed_commitment_tx {
2306 if input.previous_output.txid == current_local_signed_commitment_tx.txid {
2307 scan_commitment!(current_local_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2308 "our latest local commitment tx", true);
2311 if let Some(ref prev_local_signed_commitment_tx) = self.prev_local_signed_commitment_tx {
2312 if input.previous_output.txid == prev_local_signed_commitment_tx.txid {
2313 scan_commitment!(prev_local_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2314 "our previous local commitment tx", true);
2317 if let Some(ref htlc_outputs) = self.remote_claimable_outpoints.get(&input.previous_output.txid) {
2318 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
2319 "remote commitment tx", false);
2322 // Check that scan_commitment, above, decided there is some source worth relaying an
2323 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
2324 if let Some((source, payment_hash)) = payment_data {
2325 let mut payment_preimage = PaymentPreimage([0; 32]);
2326 if accepted_preimage_claim {
2327 if !self.pending_htlcs_updated.iter().any(|update| update.source == source) {
2328 payment_preimage.0.copy_from_slice(&input.witness[3]);
2329 self.pending_htlcs_updated.push(HTLCUpdate {
2331 payment_preimage: Some(payment_preimage),
2335 } else if offered_preimage_claim {
2336 if !self.pending_htlcs_updated.iter().any(|update| update.source == source) {
2337 payment_preimage.0.copy_from_slice(&input.witness[1]);
2338 self.pending_htlcs_updated.push(HTLCUpdate {
2340 payment_preimage: Some(payment_preimage),
2345 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);
2346 match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
2347 hash_map::Entry::Occupied(mut entry) => {
2348 let e = entry.get_mut();
2349 e.retain(|ref event| {
2351 OnchainEvent::HTLCUpdate { ref htlc_update } => {
2352 return htlc_update.0 != source
2356 e.push(OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)});
2358 hash_map::Entry::Vacant(entry) => {
2359 entry.insert(vec![OnchainEvent::HTLCUpdate { htlc_update: (source, payment_hash)}]);
2368 const MAX_ALLOC_SIZE: usize = 64*1024;
2370 impl<ChanSigner: ChannelKeys + Readable> ReadableArgs<Arc<Logger>> for (Sha256dHash, ChannelMonitor<ChanSigner>) {
2371 fn read<R: ::std::io::Read>(reader: &mut R, logger: Arc<Logger>) -> Result<Self, DecodeError> {
2372 macro_rules! unwrap_obj {
2376 Err(_) => return Err(DecodeError::InvalidValue),
2381 let _ver: u8 = Readable::read(reader)?;
2382 let min_ver: u8 = Readable::read(reader)?;
2383 if min_ver > SERIALIZATION_VERSION {
2384 return Err(DecodeError::UnknownVersion);
2387 let latest_update_id: u64 = Readable::read(reader)?;
2388 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
2390 let key_storage = match <u8 as Readable>::read(reader)? {
2392 let keys = Readable::read(reader)?;
2393 let funding_key = Readable::read(reader)?;
2394 let revocation_base_key = Readable::read(reader)?;
2395 let htlc_base_key = Readable::read(reader)?;
2396 let delayed_payment_base_key = Readable::read(reader)?;
2397 let payment_base_key = Readable::read(reader)?;
2398 let shutdown_pubkey = Readable::read(reader)?;
2399 // Technically this can fail and serialize fail a round-trip, but only for serialization of
2400 // barely-init'd ChannelMonitors that we can't do anything with.
2401 let outpoint = OutPoint {
2402 txid: Readable::read(reader)?,
2403 index: Readable::read(reader)?,
2405 let funding_info = Some((outpoint, Readable::read(reader)?));
2406 let current_remote_commitment_txid = Readable::read(reader)?;
2407 let prev_remote_commitment_txid = Readable::read(reader)?;
2411 revocation_base_key,
2413 delayed_payment_base_key,
2417 current_remote_commitment_txid,
2418 prev_remote_commitment_txid,
2421 _ => return Err(DecodeError::InvalidValue),
2424 let their_htlc_base_key = Some(Readable::read(reader)?);
2425 let their_delayed_payment_base_key = Some(Readable::read(reader)?);
2426 let funding_redeemscript = Some(Readable::read(reader)?);
2427 let channel_value_satoshis = Some(Readable::read(reader)?);
2429 let their_cur_revocation_points = {
2430 let first_idx = <U48 as Readable>::read(reader)?.0;
2434 let first_point = Readable::read(reader)?;
2435 let second_point_slice: [u8; 33] = Readable::read(reader)?;
2436 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
2437 Some((first_idx, first_point, None))
2439 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
2444 let our_to_self_delay: u16 = Readable::read(reader)?;
2445 let their_to_self_delay: Option<u16> = Some(Readable::read(reader)?);
2447 let commitment_secrets = Readable::read(reader)?;
2449 macro_rules! read_htlc_in_commitment {
2452 let offered: bool = Readable::read(reader)?;
2453 let amount_msat: u64 = Readable::read(reader)?;
2454 let cltv_expiry: u32 = Readable::read(reader)?;
2455 let payment_hash: PaymentHash = Readable::read(reader)?;
2456 let transaction_output_index: Option<u32> = Readable::read(reader)?;
2458 HTLCOutputInCommitment {
2459 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
2465 let remote_claimable_outpoints_len: u64 = Readable::read(reader)?;
2466 let mut remote_claimable_outpoints = HashMap::with_capacity(cmp::min(remote_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
2467 for _ in 0..remote_claimable_outpoints_len {
2468 let txid: Sha256dHash = Readable::read(reader)?;
2469 let htlcs_count: u64 = Readable::read(reader)?;
2470 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
2471 for _ in 0..htlcs_count {
2472 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
2474 if let Some(_) = remote_claimable_outpoints.insert(txid, htlcs) {
2475 return Err(DecodeError::InvalidValue);
2479 let remote_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
2480 let mut remote_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(remote_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
2481 for _ in 0..remote_commitment_txn_on_chain_len {
2482 let txid: Sha256dHash = Readable::read(reader)?;
2483 let commitment_number = <U48 as Readable>::read(reader)?.0;
2484 let outputs_count = <u64 as Readable>::read(reader)?;
2485 let mut outputs = Vec::with_capacity(cmp::min(outputs_count as usize, MAX_ALLOC_SIZE / 8));
2486 for _ in 0..outputs_count {
2487 outputs.push(Readable::read(reader)?);
2489 if let Some(_) = remote_commitment_txn_on_chain.insert(txid, (commitment_number, outputs)) {
2490 return Err(DecodeError::InvalidValue);
2494 let remote_hash_commitment_number_len: u64 = Readable::read(reader)?;
2495 let mut remote_hash_commitment_number = HashMap::with_capacity(cmp::min(remote_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
2496 for _ in 0..remote_hash_commitment_number_len {
2497 let payment_hash: PaymentHash = Readable::read(reader)?;
2498 let commitment_number = <U48 as Readable>::read(reader)?.0;
2499 if let Some(_) = remote_hash_commitment_number.insert(payment_hash, commitment_number) {
2500 return Err(DecodeError::InvalidValue);
2504 macro_rules! read_local_tx {
2507 let tx = <LocalCommitmentTransaction as Readable>::read(reader)?;
2508 let revocation_key = Readable::read(reader)?;
2509 let a_htlc_key = Readable::read(reader)?;
2510 let b_htlc_key = Readable::read(reader)?;
2511 let delayed_payment_key = Readable::read(reader)?;
2512 let per_commitment_point = Readable::read(reader)?;
2513 let feerate_per_kw: u64 = Readable::read(reader)?;
2515 let htlcs_len: u64 = Readable::read(reader)?;
2516 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_len as usize, MAX_ALLOC_SIZE / 128));
2517 for _ in 0..htlcs_len {
2518 let htlc = read_htlc_in_commitment!();
2519 let sigs = match <u8 as Readable>::read(reader)? {
2521 1 => Some(Readable::read(reader)?),
2522 _ => return Err(DecodeError::InvalidValue),
2524 htlcs.push((htlc, sigs, Readable::read(reader)?));
2529 tx, revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, per_commitment_point, feerate_per_kw,
2536 let prev_local_signed_commitment_tx = match <u8 as Readable>::read(reader)? {
2539 Some(read_local_tx!())
2541 _ => return Err(DecodeError::InvalidValue),
2544 let current_local_signed_commitment_tx = match <u8 as Readable>::read(reader)? {
2547 Some(read_local_tx!())
2549 _ => return Err(DecodeError::InvalidValue),
2552 let current_remote_commitment_number = <U48 as Readable>::read(reader)?.0;
2554 let payment_preimages_len: u64 = Readable::read(reader)?;
2555 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
2556 for _ in 0..payment_preimages_len {
2557 let preimage: PaymentPreimage = Readable::read(reader)?;
2558 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2559 if let Some(_) = payment_preimages.insert(hash, preimage) {
2560 return Err(DecodeError::InvalidValue);
2564 let pending_htlcs_updated_len: u64 = Readable::read(reader)?;
2565 let mut pending_htlcs_updated = Vec::with_capacity(cmp::min(pending_htlcs_updated_len as usize, MAX_ALLOC_SIZE / (32 + 8*3)));
2566 for _ in 0..pending_htlcs_updated_len {
2567 pending_htlcs_updated.push(Readable::read(reader)?);
2570 let pending_events_len: u64 = Readable::read(reader)?;
2571 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<events::Event>()));
2572 for _ in 0..pending_events_len {
2573 if let Some(event) = MaybeReadable::read(reader)? {
2574 pending_events.push(event);
2578 let last_block_hash: Sha256dHash = Readable::read(reader)?;
2579 let to_remote_rescue = match <u8 as Readable>::read(reader)? {
2582 let to_remote_script = Readable::read(reader)?;
2583 let local_key = Readable::read(reader)?;
2584 Some((to_remote_script, local_key))
2586 _ => return Err(DecodeError::InvalidValue),
2589 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
2590 let mut onchain_events_waiting_threshold_conf = HashMap::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
2591 for _ in 0..waiting_threshold_conf_len {
2592 let height_target = Readable::read(reader)?;
2593 let events_len: u64 = Readable::read(reader)?;
2594 let mut events = Vec::with_capacity(cmp::min(events_len as usize, MAX_ALLOC_SIZE / 128));
2595 for _ in 0..events_len {
2596 let ev = match <u8 as Readable>::read(reader)? {
2598 let htlc_source = Readable::read(reader)?;
2599 let hash = Readable::read(reader)?;
2600 OnchainEvent::HTLCUpdate {
2601 htlc_update: (htlc_source, hash)
2604 _ => return Err(DecodeError::InvalidValue),
2608 onchain_events_waiting_threshold_conf.insert(height_target, events);
2611 let outputs_to_watch_len: u64 = Readable::read(reader)?;
2612 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>>())));
2613 for _ in 0..outputs_to_watch_len {
2614 let txid = Readable::read(reader)?;
2615 let outputs_len: u64 = Readable::read(reader)?;
2616 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Script>()));
2617 for _ in 0..outputs_len {
2618 outputs.push(Readable::read(reader)?);
2620 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
2621 return Err(DecodeError::InvalidValue);
2624 let onchain_tx_handler = ReadableArgs::read(reader, logger.clone())?;
2626 Ok((last_block_hash.clone(), ChannelMonitor {
2628 commitment_transaction_number_obscure_factor,
2631 their_htlc_base_key,
2632 their_delayed_payment_base_key,
2633 funding_redeemscript,
2634 channel_value_satoshis,
2635 their_cur_revocation_points,
2638 their_to_self_delay,
2641 remote_claimable_outpoints,
2642 remote_commitment_txn_on_chain,
2643 remote_hash_commitment_number,
2645 prev_local_signed_commitment_tx,
2646 current_local_signed_commitment_tx,
2647 current_remote_commitment_number,
2650 pending_htlcs_updated,
2655 onchain_events_waiting_threshold_conf,
2661 secp_ctx: Secp256k1::new(),
2669 use bitcoin::blockdata::script::{Script, Builder};
2670 use bitcoin::blockdata::opcodes;
2671 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, SigHashType};
2672 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
2673 use bitcoin::util::bip143;
2674 use bitcoin_hashes::Hash;
2675 use bitcoin_hashes::sha256::Hash as Sha256;
2676 use bitcoin_hashes::sha256d::Hash as Sha256dHash;
2677 use bitcoin_hashes::hex::FromHex;
2679 use chain::transaction::OutPoint;
2680 use ln::channelmanager::{PaymentPreimage, PaymentHash};
2681 use ln::channelmonitor::ChannelMonitor;
2682 use ln::onchaintx::{OnchainTxHandler, InputDescriptors};
2684 use ln::chan_utils::{HTLCOutputInCommitment, TxCreationKeys, LocalCommitmentTransaction};
2685 use util::test_utils::TestLogger;
2686 use secp256k1::key::{SecretKey,PublicKey};
2687 use secp256k1::Secp256k1;
2688 use rand::{thread_rng,Rng};
2690 use chain::keysinterface::InMemoryChannelKeys;
2693 fn test_prune_preimages() {
2694 let secp_ctx = Secp256k1::new();
2695 let logger = Arc::new(TestLogger::new());
2697 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
2698 macro_rules! dummy_keys {
2702 per_commitment_point: dummy_key.clone(),
2703 revocation_key: dummy_key.clone(),
2704 a_htlc_key: dummy_key.clone(),
2705 b_htlc_key: dummy_key.clone(),
2706 a_delayed_payment_key: dummy_key.clone(),
2707 b_payment_key: dummy_key.clone(),
2712 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2714 let mut preimages = Vec::new();
2716 let mut rng = thread_rng();
2718 let mut preimage = PaymentPreimage([0; 32]);
2719 rng.fill_bytes(&mut preimage.0[..]);
2720 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
2721 preimages.push((preimage, hash));
2725 macro_rules! preimages_slice_to_htlc_outputs {
2726 ($preimages_slice: expr) => {
2728 let mut res = Vec::new();
2729 for (idx, preimage) in $preimages_slice.iter().enumerate() {
2730 res.push((HTLCOutputInCommitment {
2734 payment_hash: preimage.1.clone(),
2735 transaction_output_index: Some(idx as u32),
2742 macro_rules! preimages_to_local_htlcs {
2743 ($preimages_slice: expr) => {
2745 let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
2746 let res: Vec<_> = inp.drain(..).map(|e| { (e.0, None, e.1) }).collect();
2752 macro_rules! test_preimages_exist {
2753 ($preimages_slice: expr, $monitor: expr) => {
2754 for preimage in $preimages_slice {
2755 assert!($monitor.payment_preimages.contains_key(&preimage.1));
2760 let keys = InMemoryChannelKeys::new(
2762 SecretKey::from_slice(&[41; 32]).unwrap(),
2763 SecretKey::from_slice(&[41; 32]).unwrap(),
2764 SecretKey::from_slice(&[41; 32]).unwrap(),
2765 SecretKey::from_slice(&[41; 32]).unwrap(),
2766 SecretKey::from_slice(&[41; 32]).unwrap(),
2771 // Prune with one old state and a local commitment tx holding a few overlaps with the
2773 let mut monitor = ChannelMonitor::new(keys,
2774 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()), 0, &Script::new(),
2775 (OutPoint { txid: Sha256dHash::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
2776 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
2777 &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
2778 0, Script::new(), 46, 0, logger.clone());
2780 monitor.their_to_self_delay = Some(10);
2782 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..10])).unwrap();
2783 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key);
2784 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key);
2785 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key);
2786 monitor.provide_latest_remote_commitment_tx_info(&dummy_tx, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key);
2787 for &(ref preimage, ref hash) in preimages.iter() {
2788 monitor.provide_payment_preimage(hash, preimage);
2791 // Now provide a secret, pruning preimages 10-15
2792 let mut secret = [0; 32];
2793 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
2794 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
2795 assert_eq!(monitor.payment_preimages.len(), 15);
2796 test_preimages_exist!(&preimages[0..10], monitor);
2797 test_preimages_exist!(&preimages[15..20], monitor);
2799 // Now provide a further secret, pruning preimages 15-17
2800 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
2801 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
2802 assert_eq!(monitor.payment_preimages.len(), 13);
2803 test_preimages_exist!(&preimages[0..10], monitor);
2804 test_preimages_exist!(&preimages[17..20], monitor);
2806 // Now update local commitment tx info, pruning only element 18 as we still care about the
2807 // previous commitment tx's preimages too
2808 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..5])).unwrap();
2809 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
2810 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
2811 assert_eq!(monitor.payment_preimages.len(), 12);
2812 test_preimages_exist!(&preimages[0..10], monitor);
2813 test_preimages_exist!(&preimages[18..20], monitor);
2815 // But if we do it again, we'll prune 5-10
2816 monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..3])).unwrap();
2817 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
2818 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
2819 assert_eq!(monitor.payment_preimages.len(), 5);
2820 test_preimages_exist!(&preimages[0..5], monitor);
2824 fn test_claim_txn_weight_computation() {
2825 // We test Claim txn weight, knowing that we want expected weigth and
2826 // not actual case to avoid sigs and time-lock delays hell variances.
2828 let secp_ctx = Secp256k1::new();
2829 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
2830 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
2831 let mut sum_actual_sigs = 0;
2833 macro_rules! sign_input {
2834 ($sighash_parts: expr, $input: expr, $idx: expr, $amount: expr, $input_type: expr, $sum_actual_sigs: expr) => {
2835 let htlc = HTLCOutputInCommitment {
2836 offered: if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::OfferedHTLC { true } else { false },
2838 cltv_expiry: 2 << 16,
2839 payment_hash: PaymentHash([1; 32]),
2840 transaction_output_index: Some($idx),
2842 let redeem_script = if *$input_type == InputDescriptors::RevokedOutput { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &pubkey, &pubkey, &pubkey) };
2843 let sighash = hash_to_message!(&$sighash_parts.sighash_all(&$input, &redeem_script, $amount)[..]);
2844 let sig = secp_ctx.sign(&sighash, &privkey);
2845 $input.witness.push(sig.serialize_der().to_vec());
2846 $input.witness[0].push(SigHashType::All as u8);
2847 sum_actual_sigs += $input.witness[0].len();
2848 if *$input_type == InputDescriptors::RevokedOutput {
2849 $input.witness.push(vec!(1));
2850 } else if *$input_type == InputDescriptors::RevokedOfferedHTLC || *$input_type == InputDescriptors::RevokedReceivedHTLC {
2851 $input.witness.push(pubkey.clone().serialize().to_vec());
2852 } else if *$input_type == InputDescriptors::ReceivedHTLC {
2853 $input.witness.push(vec![0]);
2855 $input.witness.push(PaymentPreimage([1; 32]).0.to_vec());
2857 $input.witness.push(redeem_script.into_bytes());
2858 println!("witness[0] {}", $input.witness[0].len());
2859 println!("witness[1] {}", $input.witness[1].len());
2860 println!("witness[2] {}", $input.witness[2].len());
2864 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
2865 let txid = Sha256dHash::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
2867 // Justice tx with 1 to_local, 2 revoked offered HTLCs, 1 revoked received HTLCs
2868 let mut claim_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
2870 claim_tx.input.push(TxIn {
2871 previous_output: BitcoinOutPoint {
2875 script_sig: Script::new(),
2876 sequence: 0xfffffffd,
2877 witness: Vec::new(),
2880 claim_tx.output.push(TxOut {
2881 script_pubkey: script_pubkey.clone(),
2884 let base_weight = claim_tx.get_weight();
2885 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2886 let inputs_des = vec![InputDescriptors::RevokedOutput, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedOfferedHTLC, InputDescriptors::RevokedReceivedHTLC];
2887 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2888 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2890 assert_eq!(base_weight + OnchainTxHandler::get_witnesses_weight(&inputs_des[..]), claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_des.len() - sum_actual_sigs));
2892 // Claim tx with 1 offered HTLCs, 3 received HTLCs
2893 claim_tx.input.clear();
2894 sum_actual_sigs = 0;
2896 claim_tx.input.push(TxIn {
2897 previous_output: BitcoinOutPoint {
2901 script_sig: Script::new(),
2902 sequence: 0xfffffffd,
2903 witness: Vec::new(),
2906 let base_weight = claim_tx.get_weight();
2907 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2908 let inputs_des = vec![InputDescriptors::OfferedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC, InputDescriptors::ReceivedHTLC];
2909 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2910 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2912 assert_eq!(base_weight + OnchainTxHandler::get_witnesses_weight(&inputs_des[..]), claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_des.len() - sum_actual_sigs));
2914 // Justice tx with 1 revoked HTLC-Success tx output
2915 claim_tx.input.clear();
2916 sum_actual_sigs = 0;
2917 claim_tx.input.push(TxIn {
2918 previous_output: BitcoinOutPoint {
2922 script_sig: Script::new(),
2923 sequence: 0xfffffffd,
2924 witness: Vec::new(),
2926 let base_weight = claim_tx.get_weight();
2927 let sighash_parts = bip143::SighashComponents::new(&claim_tx);
2928 let inputs_des = vec![InputDescriptors::RevokedOutput];
2929 for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
2930 sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
2932 assert_eq!(base_weight + OnchainTxHandler::get_witnesses_weight(&inputs_des[..]), claim_tx.get_weight() + /* max_length_isg */ (73 * inputs_des.len() - sum_actual_sigs));
2935 // Further testing is done in the ChannelManager integration tests.