1 // This file is Copyright its original authors, visible in version control
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
7 // You may not use this file except in accordance with one or both of these
10 //! Logic to connect off-chain channel management with on-chain transaction monitoring.
12 //! [`ChainMonitor`] is an implementation of [`chain::Watch`] used both to process blocks and to
13 //! update [`ChannelMonitor`]s accordingly. If any on-chain events need further processing, it will
14 //! make those available as [`MonitorEvent`]s to be consumed.
16 //! [`ChainMonitor`] is parameterized by an optional chain source, which must implement the
17 //! [`chain::Filter`] trait. This provides a mechanism to signal new relevant outputs back to light
18 //! clients, such that transactions spending those outputs are included in block data.
20 //! [`ChainMonitor`] may be used directly to monitor channels locally or as a part of a distributed
21 //! setup to monitor channels remotely. In the latter case, a custom [`chain::Watch`] implementation
22 //! would be responsible for routing each update to a remote server and for retrieving monitor
23 //! events. The remote server would make use of [`ChainMonitor`] for block processing and for
24 //! servicing [`ChannelMonitor`] updates from the client.
26 use bitcoin::blockdata::block::BlockHeader;
27 use bitcoin::hash_types::{Txid, BlockHash};
30 use crate::chain::{ChannelMonitorUpdateStatus, Filter, WatchedOutput};
31 use crate::chain::chaininterface::{BroadcasterInterface, FeeEstimator};
32 use crate::chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, Balance, MonitorEvent, TransactionOutputs, LATENCY_GRACE_PERIOD_BLOCKS};
33 use crate::chain::transaction::{OutPoint, TransactionData};
34 use crate::sign::WriteableEcdsaChannelSigner;
36 use crate::events::{Event, EventHandler};
37 use crate::util::atomic_counter::AtomicCounter;
38 use crate::util::logger::Logger;
39 use crate::util::errors::APIError;
40 use crate::util::wakers::{Future, Notifier};
41 use crate::ln::channelmanager::ChannelDetails;
43 use crate::prelude::*;
44 use crate::sync::{RwLock, RwLockReadGuard, Mutex, MutexGuard};
45 use core::iter::FromIterator;
47 use core::sync::atomic::{AtomicBool, AtomicUsize, Ordering};
48 use bitcoin::secp256k1::PublicKey;
50 #[derive(Clone, Copy, Hash, PartialEq, Eq)]
51 /// A specific update's ID stored in a `MonitorUpdateId`, separated out to make the contents
54 /// An update that was generated by the `ChannelManager` (via our `chain::Watch`
55 /// implementation). This corresponds to an actual [`ChannelMonitorUpdate::update_id`] field
56 /// and [`ChannelMonitor::get_latest_update_id`].
58 /// An update that was generated during blockchain processing. The ID here is specific to the
59 /// generating [`ChainMonitor`] and does *not* correspond to any on-disk IDs.
63 /// An opaque identifier describing a specific [`Persist`] method call.
64 #[derive(Clone, Copy, Hash, PartialEq, Eq)]
65 pub struct MonitorUpdateId {
66 contents: UpdateOrigin,
69 impl MonitorUpdateId {
70 pub(crate) fn from_monitor_update(update: &ChannelMonitorUpdate) -> Self {
71 Self { contents: UpdateOrigin::OffChain(update.update_id) }
73 pub(crate) fn from_new_monitor<ChannelSigner: WriteableEcdsaChannelSigner>(monitor: &ChannelMonitor<ChannelSigner>) -> Self {
74 Self { contents: UpdateOrigin::OffChain(monitor.get_latest_update_id()) }
78 /// `Persist` defines behavior for persisting channel monitors: this could mean
79 /// writing once to disk, and/or uploading to one or more backup services.
81 /// Each method can return two possible values:
82 /// * If persistence (including any relevant `fsync()` calls) happens immediately, the
83 /// implementation should return [`ChannelMonitorUpdateStatus::Completed`], indicating normal
84 /// channel operation should continue.
85 /// * If persistence happens asynchronously, implementations should first ensure the
86 /// [`ChannelMonitor`] or [`ChannelMonitorUpdate`] are written durably to disk, and then return
87 /// [`ChannelMonitorUpdateStatus::InProgress`] while the update continues in the background.
88 /// Once the update completes, [`ChainMonitor::channel_monitor_updated`] should be called with
89 /// the corresponding [`MonitorUpdateId`].
91 /// Note that unlike the direct [`chain::Watch`] interface,
92 /// [`ChainMonitor::channel_monitor_updated`] must be called once for *each* update which occurs.
94 /// If persistence fails for some reason, implementations should still return
95 /// [`ChannelMonitorUpdateStatus::InProgress`] and attempt to shut down or otherwise resolve the
98 /// Third-party watchtowers may be built as a part of an implementation of this trait, with the
99 /// advantage that you can control whether to resume channel operation depending on if an update
100 /// has been persisted to a watchtower. For this, you may find the following methods useful:
101 /// [`ChannelMonitor::initial_counterparty_commitment_tx`],
102 /// [`ChannelMonitor::counterparty_commitment_txs_from_update`],
103 /// [`ChannelMonitor::sign_to_local_justice_tx`], [`TrustedCommitmentTransaction::revokeable_output_index`],
104 /// [`TrustedCommitmentTransaction::build_to_local_justice_tx`].
106 /// [`TrustedCommitmentTransaction::revokeable_output_index`]: crate::ln::chan_utils::TrustedCommitmentTransaction::revokeable_output_index
107 /// [`TrustedCommitmentTransaction::build_to_local_justice_tx`]: crate::ln::chan_utils::TrustedCommitmentTransaction::build_to_local_justice_tx
108 pub trait Persist<ChannelSigner: WriteableEcdsaChannelSigner> {
109 /// Persist a new channel's data in response to a [`chain::Watch::watch_channel`] call. This is
110 /// called by [`ChannelManager`] for new channels, or may be called directly, e.g. on startup.
112 /// The data can be stored any way you want, but the identifier provided by LDK is the
113 /// channel's outpoint (and it is up to you to maintain a correct mapping between the outpoint
114 /// and the stored channel data). Note that you **must** persist every new monitor to disk.
116 /// The `update_id` is used to identify this call to [`ChainMonitor::channel_monitor_updated`],
117 /// if you return [`ChannelMonitorUpdateStatus::InProgress`].
119 /// See [`Writeable::write`] on [`ChannelMonitor`] for writing out a `ChannelMonitor`
120 /// and [`ChannelMonitorUpdateStatus`] for requirements when returning errors.
122 /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
123 /// [`Writeable::write`]: crate::util::ser::Writeable::write
124 fn persist_new_channel(&self, channel_id: OutPoint, data: &ChannelMonitor<ChannelSigner>, update_id: MonitorUpdateId) -> ChannelMonitorUpdateStatus;
126 /// Update one channel's data. The provided [`ChannelMonitor`] has already applied the given
129 /// Note that on every update, you **must** persist either the [`ChannelMonitorUpdate`] or the
130 /// updated monitor itself to disk/backups. See the [`Persist`] trait documentation for more
133 /// During blockchain synchronization operations, this may be called with no
134 /// [`ChannelMonitorUpdate`], in which case the full [`ChannelMonitor`] needs to be persisted.
135 /// Note that after the full [`ChannelMonitor`] is persisted any previous
136 /// [`ChannelMonitorUpdate`]s which were persisted should be discarded - they can no longer be
137 /// applied to the persisted [`ChannelMonitor`] as they were already applied.
139 /// If an implementer chooses to persist the updates only, they need to make
140 /// sure that all the updates are applied to the `ChannelMonitors` *before*
141 /// the set of channel monitors is given to the `ChannelManager`
142 /// deserialization routine. See [`ChannelMonitor::update_monitor`] for
143 /// applying a monitor update to a monitor. If full `ChannelMonitors` are
144 /// persisted, then there is no need to persist individual updates.
146 /// Note that there could be a performance tradeoff between persisting complete
147 /// channel monitors on every update vs. persisting only updates and applying
148 /// them in batches. The size of each monitor grows `O(number of state updates)`
149 /// whereas updates are small and `O(1)`.
151 /// The `update_id` is used to identify this call to [`ChainMonitor::channel_monitor_updated`],
152 /// if you return [`ChannelMonitorUpdateStatus::InProgress`].
154 /// See [`Writeable::write`] on [`ChannelMonitor`] for writing out a `ChannelMonitor`,
155 /// [`Writeable::write`] on [`ChannelMonitorUpdate`] for writing out an update, and
156 /// [`ChannelMonitorUpdateStatus`] for requirements when returning errors.
158 /// [`Writeable::write`]: crate::util::ser::Writeable::write
159 fn update_persisted_channel(&self, channel_id: OutPoint, update: Option<&ChannelMonitorUpdate>, data: &ChannelMonitor<ChannelSigner>, update_id: MonitorUpdateId) -> ChannelMonitorUpdateStatus;
162 struct MonitorHolder<ChannelSigner: WriteableEcdsaChannelSigner> {
163 monitor: ChannelMonitor<ChannelSigner>,
164 /// The full set of pending monitor updates for this Channel.
166 /// Note that this lock must be held during updates to prevent a race where we call
167 /// update_persisted_channel, the user returns a
168 /// [`ChannelMonitorUpdateStatus::InProgress`], and then calls channel_monitor_updated
169 /// immediately, racing our insertion of the pending update into the contained Vec.
171 /// Beyond the synchronization of updates themselves, we cannot handle user events until after
172 /// any chain updates have been stored on disk. Thus, we scan this list when returning updates
173 /// to the ChannelManager, refusing to return any updates for a ChannelMonitor which is still
174 /// being persisted fully to disk after a chain update.
176 /// This avoids the possibility of handling, e.g. an on-chain claim, generating a claim monitor
177 /// event, resulting in the relevant ChannelManager generating a PaymentSent event and dropping
178 /// the pending payment entry, and then reloading before the monitor is persisted, resulting in
179 /// the ChannelManager re-adding the same payment entry, before the same block is replayed,
180 /// resulting in a duplicate PaymentSent event.
181 pending_monitor_updates: Mutex<Vec<MonitorUpdateId>>,
182 /// When the user returns a PermanentFailure error from an update_persisted_channel call during
183 /// block processing, we inform the ChannelManager that the channel should be closed
184 /// asynchronously. In order to ensure no further changes happen before the ChannelManager has
185 /// processed the closure event, we set this to true and return PermanentFailure for any other
186 /// chain::Watch events.
187 channel_perm_failed: AtomicBool,
188 /// The last block height at which no [`UpdateOrigin::ChainSync`] monitor updates were present
189 /// in `pending_monitor_updates`.
190 /// If it's been more than [`LATENCY_GRACE_PERIOD_BLOCKS`] since we started waiting on a chain
191 /// sync event, we let monitor events return to `ChannelManager` because we cannot hold them up
192 /// forever or we'll end up with HTLC preimages waiting to feed back into an upstream channel
193 /// forever, risking funds loss.
194 last_chain_persist_height: AtomicUsize,
197 impl<ChannelSigner: WriteableEcdsaChannelSigner> MonitorHolder<ChannelSigner> {
198 fn has_pending_offchain_updates(&self, pending_monitor_updates_lock: &MutexGuard<Vec<MonitorUpdateId>>) -> bool {
199 pending_monitor_updates_lock.iter().any(|update_id|
200 if let UpdateOrigin::OffChain(_) = update_id.contents { true } else { false })
202 fn has_pending_chainsync_updates(&self, pending_monitor_updates_lock: &MutexGuard<Vec<MonitorUpdateId>>) -> bool {
203 pending_monitor_updates_lock.iter().any(|update_id|
204 if let UpdateOrigin::ChainSync(_) = update_id.contents { true } else { false })
208 /// A read-only reference to a current ChannelMonitor.
210 /// Note that this holds a mutex in [`ChainMonitor`] and may block other events until it is
212 pub struct LockedChannelMonitor<'a, ChannelSigner: WriteableEcdsaChannelSigner> {
213 lock: RwLockReadGuard<'a, HashMap<OutPoint, MonitorHolder<ChannelSigner>>>,
214 funding_txo: OutPoint,
217 impl<ChannelSigner: WriteableEcdsaChannelSigner> Deref for LockedChannelMonitor<'_, ChannelSigner> {
218 type Target = ChannelMonitor<ChannelSigner>;
219 fn deref(&self) -> &ChannelMonitor<ChannelSigner> {
220 &self.lock.get(&self.funding_txo).expect("Checked at construction").monitor
224 /// An implementation of [`chain::Watch`] for monitoring channels.
226 /// Connected and disconnected blocks must be provided to `ChainMonitor` as documented by
227 /// [`chain::Watch`]. May be used in conjunction with [`ChannelManager`] to monitor channels locally
228 /// or used independently to monitor channels remotely. See the [module-level documentation] for
231 /// Note that `ChainMonitor` should regularly trigger rebroadcasts/fee bumps of pending claims from
232 /// a force-closed channel. This is crucial in preventing certain classes of pinning attacks,
233 /// detecting substantial mempool feerate changes between blocks, and ensuring reliability if
234 /// broadcasting fails. We recommend invoking this every 30 seconds, or lower if running in an
235 /// environment with spotty connections, like on mobile.
237 /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
238 /// [module-level documentation]: crate::chain::chainmonitor
239 /// [`rebroadcast_pending_claims`]: Self::rebroadcast_pending_claims
240 pub struct ChainMonitor<ChannelSigner: WriteableEcdsaChannelSigner, C: Deref, T: Deref, F: Deref, L: Deref, P: Deref>
241 where C::Target: chain::Filter,
242 T::Target: BroadcasterInterface,
243 F::Target: FeeEstimator,
245 P::Target: Persist<ChannelSigner>,
247 monitors: RwLock<HashMap<OutPoint, MonitorHolder<ChannelSigner>>>,
248 /// When we generate a [`MonitorUpdateId`] for a chain-event monitor persistence, we need a
249 /// unique ID, which we calculate by simply getting the next value from this counter. Note that
250 /// the ID is never persisted so it's ok that they reset on restart.
251 sync_persistence_id: AtomicCounter,
252 chain_source: Option<C>,
257 /// "User-provided" (ie persistence-completion/-failed) [`MonitorEvent`]s. These came directly
258 /// from the user and not from a [`ChannelMonitor`].
259 pending_monitor_events: Mutex<Vec<(OutPoint, Vec<MonitorEvent>, Option<PublicKey>)>>,
260 /// The best block height seen, used as a proxy for the passage of time.
261 highest_chain_height: AtomicUsize,
263 event_notifier: Notifier,
266 impl<ChannelSigner: WriteableEcdsaChannelSigner, C: Deref, T: Deref, F: Deref, L: Deref, P: Deref> ChainMonitor<ChannelSigner, C, T, F, L, P>
267 where C::Target: chain::Filter,
268 T::Target: BroadcasterInterface,
269 F::Target: FeeEstimator,
271 P::Target: Persist<ChannelSigner>,
273 /// Dispatches to per-channel monitors, which are responsible for updating their on-chain view
274 /// of a channel and reacting accordingly based on transactions in the given chain data. See
275 /// [`ChannelMonitor::block_connected`] for details. Any HTLCs that were resolved on chain will
276 /// be returned by [`chain::Watch::release_pending_monitor_events`].
278 /// Calls back to [`chain::Filter`] if any monitor indicated new outputs to watch. Subsequent
279 /// calls must not exclude any transactions matching the new outputs nor any in-block
280 /// descendants of such transactions. It is not necessary to re-fetch the block to obtain
281 /// updated `txdata`.
283 /// Calls which represent a new blockchain tip height should set `best_height`.
284 fn process_chain_data<FN>(&self, header: &BlockHeader, best_height: Option<u32>, txdata: &TransactionData, process: FN)
286 FN: Fn(&ChannelMonitor<ChannelSigner>, &TransactionData) -> Vec<TransactionOutputs>
288 let funding_outpoints: HashSet<OutPoint> = HashSet::from_iter(self.monitors.read().unwrap().keys().cloned());
289 for funding_outpoint in funding_outpoints.iter() {
290 let monitor_lock = self.monitors.read().unwrap();
291 if let Some(monitor_state) = monitor_lock.get(funding_outpoint) {
292 self.update_monitor_with_chain_data(header, best_height, txdata, &process, funding_outpoint, &monitor_state);
296 // do some followup cleanup if any funding outpoints were added in between iterations
297 let monitor_states = self.monitors.write().unwrap();
298 for (funding_outpoint, monitor_state) in monitor_states.iter() {
299 if !funding_outpoints.contains(funding_outpoint) {
300 self.update_monitor_with_chain_data(header, best_height, txdata, &process, funding_outpoint, &monitor_state);
304 if let Some(height) = best_height {
305 // If the best block height is being updated, update highest_chain_height under the
306 // monitors write lock.
307 let old_height = self.highest_chain_height.load(Ordering::Acquire);
308 let new_height = height as usize;
309 if new_height > old_height {
310 self.highest_chain_height.store(new_height, Ordering::Release);
315 fn update_monitor_with_chain_data<FN>(&self, header: &BlockHeader, best_height: Option<u32>, txdata: &TransactionData, process: FN, funding_outpoint: &OutPoint, monitor_state: &MonitorHolder<ChannelSigner>) where FN: Fn(&ChannelMonitor<ChannelSigner>, &TransactionData) -> Vec<TransactionOutputs> {
316 let monitor = &monitor_state.monitor;
319 txn_outputs = process(monitor, txdata);
320 let update_id = MonitorUpdateId {
321 contents: UpdateOrigin::ChainSync(self.sync_persistence_id.get_increment()),
323 let mut pending_monitor_updates = monitor_state.pending_monitor_updates.lock().unwrap();
324 if let Some(height) = best_height {
325 if !monitor_state.has_pending_chainsync_updates(&pending_monitor_updates) {
326 // If there are not ChainSync persists awaiting completion, go ahead and
327 // set last_chain_persist_height here - we wouldn't want the first
328 // InProgress to always immediately be considered "overly delayed".
329 monitor_state.last_chain_persist_height.store(height as usize, Ordering::Release);
333 log_trace!(self.logger, "Syncing Channel Monitor for channel {}", log_funding_info!(monitor));
334 match self.persister.update_persisted_channel(*funding_outpoint, None, monitor, update_id) {
335 ChannelMonitorUpdateStatus::Completed =>
336 log_trace!(self.logger, "Finished syncing Channel Monitor for channel {}", log_funding_info!(monitor)),
337 ChannelMonitorUpdateStatus::InProgress => {
338 log_debug!(self.logger, "Channel Monitor sync for channel {} in progress, holding events until completion!", log_funding_info!(monitor));
339 pending_monitor_updates.push(update_id);
344 // Register any new outputs with the chain source for filtering, storing any dependent
345 // transactions from within the block that previously had not been included in txdata.
346 if let Some(ref chain_source) = self.chain_source {
347 let block_hash = header.block_hash();
348 for (txid, mut outputs) in txn_outputs.drain(..) {
349 for (idx, output) in outputs.drain(..) {
350 // Register any new outputs with the chain source for filtering
351 let output = WatchedOutput {
352 block_hash: Some(block_hash),
353 outpoint: OutPoint { txid, index: idx as u16 },
354 script_pubkey: output.script_pubkey,
356 chain_source.register_output(output)
362 /// Creates a new `ChainMonitor` used to watch on-chain activity pertaining to channels.
364 /// When an optional chain source implementing [`chain::Filter`] is provided, the chain monitor
365 /// will call back to it indicating transactions and outputs of interest. This allows clients to
366 /// pre-filter blocks or only fetch blocks matching a compact filter. Otherwise, clients may
367 /// always need to fetch full blocks absent another means for determining which blocks contain
368 /// transactions relevant to the watched channels.
369 pub fn new(chain_source: Option<C>, broadcaster: T, logger: L, feeest: F, persister: P) -> Self {
371 monitors: RwLock::new(HashMap::new()),
372 sync_persistence_id: AtomicCounter::new(),
376 fee_estimator: feeest,
378 pending_monitor_events: Mutex::new(Vec::new()),
379 highest_chain_height: AtomicUsize::new(0),
380 event_notifier: Notifier::new(),
384 /// Gets the balances in the contained [`ChannelMonitor`]s which are claimable on-chain or
385 /// claims which are awaiting confirmation.
387 /// Includes the balances from each [`ChannelMonitor`] *except* those included in
388 /// `ignored_channels`.
390 /// See [`ChannelMonitor::get_claimable_balances`] for more details on the exact criteria for
391 /// inclusion in the return value.
392 pub fn get_claimable_balances(&self, ignored_channels: &[&ChannelDetails]) -> Vec<Balance> {
393 let mut ret = Vec::new();
394 let monitor_states = self.monitors.read().unwrap();
395 for (_, monitor_state) in monitor_states.iter().filter(|(funding_outpoint, _)| {
396 for chan in ignored_channels {
397 if chan.funding_txo.as_ref() == Some(funding_outpoint) {
403 ret.append(&mut monitor_state.monitor.get_claimable_balances());
408 /// Gets the [`LockedChannelMonitor`] for a given funding outpoint, returning an `Err` if no
409 /// such [`ChannelMonitor`] is currently being monitored for.
411 /// Note that the result holds a mutex over our monitor set, and should not be held
413 pub fn get_monitor(&self, funding_txo: OutPoint) -> Result<LockedChannelMonitor<'_, ChannelSigner>, ()> {
414 let lock = self.monitors.read().unwrap();
415 if lock.get(&funding_txo).is_some() {
416 Ok(LockedChannelMonitor { lock, funding_txo })
422 /// Lists the funding outpoint of each [`ChannelMonitor`] being monitored.
424 /// Note that [`ChannelMonitor`]s are not removed when a channel is closed as they are always
425 /// monitoring for on-chain state resolutions.
426 pub fn list_monitors(&self) -> Vec<OutPoint> {
427 self.monitors.read().unwrap().keys().map(|outpoint| *outpoint).collect()
430 #[cfg(not(c_bindings))]
431 /// Lists the pending updates for each [`ChannelMonitor`] (by `OutPoint` being monitored).
432 pub fn list_pending_monitor_updates(&self) -> HashMap<OutPoint, Vec<MonitorUpdateId>> {
433 self.monitors.read().unwrap().iter().map(|(outpoint, holder)| {
434 (*outpoint, holder.pending_monitor_updates.lock().unwrap().clone())
439 /// Lists the pending updates for each [`ChannelMonitor`] (by `OutPoint` being monitored).
440 pub fn list_pending_monitor_updates(&self) -> Vec<(OutPoint, Vec<MonitorUpdateId>)> {
441 self.monitors.read().unwrap().iter().map(|(outpoint, holder)| {
442 (*outpoint, holder.pending_monitor_updates.lock().unwrap().clone())
448 pub fn remove_monitor(&self, funding_txo: &OutPoint) -> ChannelMonitor<ChannelSigner> {
449 self.monitors.write().unwrap().remove(funding_txo).unwrap().monitor
452 /// Indicates the persistence of a [`ChannelMonitor`] has completed after
453 /// [`ChannelMonitorUpdateStatus::InProgress`] was returned from an update operation.
455 /// Thus, the anticipated use is, at a high level:
456 /// 1) This [`ChainMonitor`] calls [`Persist::update_persisted_channel`] which stores the
457 /// update to disk and begins updating any remote (e.g. watchtower/backup) copies,
458 /// returning [`ChannelMonitorUpdateStatus::InProgress`],
459 /// 2) once all remote copies are updated, you call this function with the
460 /// `completed_update_id` that completed, and once all pending updates have completed the
461 /// channel will be re-enabled.
462 // Note that we re-enable only after `UpdateOrigin::OffChain` updates complete, we don't
463 // care about `UpdateOrigin::ChainSync` updates for the channel state being updated. We
464 // only care about `UpdateOrigin::ChainSync` for returning `MonitorEvent`s.
466 /// Returns an [`APIError::APIMisuseError`] if `funding_txo` does not match any currently
467 /// registered [`ChannelMonitor`]s.
468 pub fn channel_monitor_updated(&self, funding_txo: OutPoint, completed_update_id: MonitorUpdateId) -> Result<(), APIError> {
469 let monitors = self.monitors.read().unwrap();
470 let monitor_data = if let Some(mon) = monitors.get(&funding_txo) { mon } else {
471 return Err(APIError::APIMisuseError { err: format!("No ChannelMonitor matching funding outpoint {:?} found", funding_txo) });
473 let mut pending_monitor_updates = monitor_data.pending_monitor_updates.lock().unwrap();
474 pending_monitor_updates.retain(|update_id| *update_id != completed_update_id);
476 match completed_update_id {
477 MonitorUpdateId { contents: UpdateOrigin::OffChain(_) } => {
478 // Note that we only check for `UpdateOrigin::OffChain` failures here - if
479 // we're being told that a `UpdateOrigin::OffChain` monitor update completed,
480 // we only care about ensuring we don't tell the `ChannelManager` to restore
481 // the channel to normal operation until all `UpdateOrigin::OffChain` updates
483 // If there's some `UpdateOrigin::ChainSync` update still pending that's okay
484 // - we can still update our channel state, just as long as we don't return
485 // `MonitorEvent`s from the monitor back to the `ChannelManager` until they
487 let monitor_is_pending_updates = monitor_data.has_pending_offchain_updates(&pending_monitor_updates);
488 if monitor_is_pending_updates || monitor_data.channel_perm_failed.load(Ordering::Acquire) {
489 // If there are still monitor updates pending (or an old monitor update
490 // finished after a later one perm-failed), we cannot yet construct an
494 self.pending_monitor_events.lock().unwrap().push((funding_txo, vec![MonitorEvent::Completed {
496 monitor_update_id: monitor_data.monitor.get_latest_update_id(),
497 }], monitor_data.monitor.get_counterparty_node_id()));
499 MonitorUpdateId { contents: UpdateOrigin::ChainSync(_) } => {
500 if !monitor_data.has_pending_chainsync_updates(&pending_monitor_updates) {
501 monitor_data.last_chain_persist_height.store(self.highest_chain_height.load(Ordering::Acquire), Ordering::Release);
502 // The next time release_pending_monitor_events is called, any events for this
503 // ChannelMonitor will be returned.
507 self.event_notifier.notify();
511 /// This wrapper avoids having to update some of our tests for now as they assume the direct
512 /// chain::Watch API wherein we mark a monitor fully-updated by just calling
513 /// channel_monitor_updated once with the highest ID.
514 #[cfg(any(test, fuzzing))]
515 pub fn force_channel_monitor_updated(&self, funding_txo: OutPoint, monitor_update_id: u64) {
516 let monitors = self.monitors.read().unwrap();
517 let counterparty_node_id = monitors.get(&funding_txo).and_then(|m| m.monitor.get_counterparty_node_id());
518 self.pending_monitor_events.lock().unwrap().push((funding_txo, vec![MonitorEvent::Completed {
521 }], counterparty_node_id));
522 self.event_notifier.notify();
525 #[cfg(any(test, feature = "_test_utils"))]
526 pub fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
527 use crate::events::EventsProvider;
528 let events = core::cell::RefCell::new(Vec::new());
529 let event_handler = |event: events::Event| events.borrow_mut().push(event);
530 self.process_pending_events(&event_handler);
534 /// Processes any events asynchronously in the order they were generated since the last call
535 /// using the given event handler.
537 /// See the trait-level documentation of [`EventsProvider`] for requirements.
539 /// [`EventsProvider`]: crate::events::EventsProvider
540 pub async fn process_pending_events_async<Future: core::future::Future, H: Fn(Event) -> Future>(
543 // Sadly we can't hold the monitors read lock through an async call. Thus we have to do a
544 // crazy dance to process a monitor's events then only remove them once we've done so.
545 let mons_to_process = self.monitors.read().unwrap().keys().cloned().collect::<Vec<_>>();
546 for funding_txo in mons_to_process {
548 super::channelmonitor::process_events_body!(
549 self.monitors.read().unwrap().get(&funding_txo).map(|m| &m.monitor), ev, handler(ev).await);
553 /// Gets a [`Future`] that completes when an event is available either via
554 /// [`chain::Watch::release_pending_monitor_events`] or
555 /// [`EventsProvider::process_pending_events`].
557 /// Note that callbacks registered on the [`Future`] MUST NOT call back into this
558 /// [`ChainMonitor`] and should instead register actions to be taken later.
560 /// [`EventsProvider::process_pending_events`]: crate::events::EventsProvider::process_pending_events
561 pub fn get_update_future(&self) -> Future {
562 self.event_notifier.get_future()
565 /// Triggers rebroadcasts/fee-bumps of pending claims from a force-closed channel. This is
566 /// crucial in preventing certain classes of pinning attacks, detecting substantial mempool
567 /// feerate changes between blocks, and ensuring reliability if broadcasting fails. We recommend
568 /// invoking this every 30 seconds, or lower if running in an environment with spotty
569 /// connections, like on mobile.
570 pub fn rebroadcast_pending_claims(&self) {
571 let monitors = self.monitors.read().unwrap();
572 for (_, monitor_holder) in &*monitors {
573 monitor_holder.monitor.rebroadcast_pending_claims(
574 &*self.broadcaster, &*self.fee_estimator, &*self.logger
580 impl<ChannelSigner: WriteableEcdsaChannelSigner, C: Deref, T: Deref, F: Deref, L: Deref, P: Deref>
581 chain::Listen for ChainMonitor<ChannelSigner, C, T, F, L, P>
583 C::Target: chain::Filter,
584 T::Target: BroadcasterInterface,
585 F::Target: FeeEstimator,
587 P::Target: Persist<ChannelSigner>,
589 fn filtered_block_connected(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
590 log_debug!(self.logger, "New best block {} at height {} provided via block_connected", header.block_hash(), height);
591 self.process_chain_data(header, Some(height), &txdata, |monitor, txdata| {
592 monitor.block_connected(
593 header, txdata, height, &*self.broadcaster, &*self.fee_estimator, &*self.logger)
597 fn block_disconnected(&self, header: &BlockHeader, height: u32) {
598 let monitor_states = self.monitors.read().unwrap();
599 log_debug!(self.logger, "Latest block {} at height {} removed via block_disconnected", header.block_hash(), height);
600 for monitor_state in monitor_states.values() {
601 monitor_state.monitor.block_disconnected(
602 header, height, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
607 impl<ChannelSigner: WriteableEcdsaChannelSigner, C: Deref, T: Deref, F: Deref, L: Deref, P: Deref>
608 chain::Confirm for ChainMonitor<ChannelSigner, C, T, F, L, P>
610 C::Target: chain::Filter,
611 T::Target: BroadcasterInterface,
612 F::Target: FeeEstimator,
614 P::Target: Persist<ChannelSigner>,
616 fn transactions_confirmed(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
617 log_debug!(self.logger, "{} provided transactions confirmed at height {} in block {}", txdata.len(), height, header.block_hash());
618 self.process_chain_data(header, None, txdata, |monitor, txdata| {
619 monitor.transactions_confirmed(
620 header, txdata, height, &*self.broadcaster, &*self.fee_estimator, &*self.logger)
624 fn transaction_unconfirmed(&self, txid: &Txid) {
625 log_debug!(self.logger, "Transaction {} reorganized out of chain", txid);
626 let monitor_states = self.monitors.read().unwrap();
627 for monitor_state in monitor_states.values() {
628 monitor_state.monitor.transaction_unconfirmed(txid, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
632 fn best_block_updated(&self, header: &BlockHeader, height: u32) {
633 log_debug!(self.logger, "New best block {} at height {} provided via best_block_updated", header.block_hash(), height);
634 self.process_chain_data(header, Some(height), &[], |monitor, txdata| {
635 // While in practice there shouldn't be any recursive calls when given empty txdata,
636 // it's still possible if a chain::Filter implementation returns a transaction.
637 debug_assert!(txdata.is_empty());
638 monitor.best_block_updated(
639 header, height, &*self.broadcaster, &*self.fee_estimator, &*self.logger)
643 fn get_relevant_txids(&self) -> Vec<(Txid, Option<BlockHash>)> {
644 let mut txids = Vec::new();
645 let monitor_states = self.monitors.read().unwrap();
646 for monitor_state in monitor_states.values() {
647 txids.append(&mut monitor_state.monitor.get_relevant_txids());
650 txids.sort_unstable();
656 impl<ChannelSigner: WriteableEcdsaChannelSigner, C: Deref , T: Deref , F: Deref , L: Deref , P: Deref >
657 chain::Watch<ChannelSigner> for ChainMonitor<ChannelSigner, C, T, F, L, P>
658 where C::Target: chain::Filter,
659 T::Target: BroadcasterInterface,
660 F::Target: FeeEstimator,
662 P::Target: Persist<ChannelSigner>,
664 /// Adds the monitor that watches the channel referred to by the given outpoint.
666 /// Calls back to [`chain::Filter`] with the funding transaction and outputs to watch.
668 /// Note that we persist the given `ChannelMonitor` while holding the `ChainMonitor`
670 fn watch_channel(&self, funding_outpoint: OutPoint, monitor: ChannelMonitor<ChannelSigner>) -> Result<ChannelMonitorUpdateStatus, ()> {
671 let mut monitors = self.monitors.write().unwrap();
672 let entry = match monitors.entry(funding_outpoint) {
673 hash_map::Entry::Occupied(_) => {
674 log_error!(self.logger, "Failed to add new channel data: channel monitor for given outpoint is already present");
677 hash_map::Entry::Vacant(e) => e,
679 log_trace!(self.logger, "Got new ChannelMonitor for channel {}", log_funding_info!(monitor));
680 let update_id = MonitorUpdateId::from_new_monitor(&monitor);
681 let mut pending_monitor_updates = Vec::new();
682 let persist_res = self.persister.persist_new_channel(funding_outpoint, &monitor, update_id);
684 ChannelMonitorUpdateStatus::InProgress => {
685 log_info!(self.logger, "Persistence of new ChannelMonitor for channel {} in progress", log_funding_info!(monitor));
686 pending_monitor_updates.push(update_id);
688 ChannelMonitorUpdateStatus::Completed => {
689 log_info!(self.logger, "Persistence of new ChannelMonitor for channel {} completed", log_funding_info!(monitor));
692 if let Some(ref chain_source) = self.chain_source {
693 monitor.load_outputs_to_watch(chain_source);
695 entry.insert(MonitorHolder {
697 pending_monitor_updates: Mutex::new(pending_monitor_updates),
698 channel_perm_failed: AtomicBool::new(false),
699 last_chain_persist_height: AtomicUsize::new(self.highest_chain_height.load(Ordering::Acquire)),
704 /// Note that we persist the given `ChannelMonitor` update while holding the
705 /// `ChainMonitor` monitors lock.
706 fn update_channel(&self, funding_txo: OutPoint, update: &ChannelMonitorUpdate) -> ChannelMonitorUpdateStatus {
707 // Update the monitor that watches the channel referred to by the given outpoint.
708 let monitors = self.monitors.read().unwrap();
709 match monitors.get(&funding_txo) {
711 log_error!(self.logger, "Failed to update channel monitor: no such monitor registered");
713 // We should never ever trigger this from within ChannelManager. Technically a
714 // user could use this object with some proxying in between which makes this
715 // possible, but in tests and fuzzing, this should be a panic.
716 #[cfg(debug_assertions)]
717 panic!("ChannelManager generated a channel update for a channel that was not yet registered!");
718 #[cfg(not(debug_assertions))]
719 ChannelMonitorUpdateStatus::InProgress
721 Some(monitor_state) => {
722 let monitor = &monitor_state.monitor;
723 log_trace!(self.logger, "Updating ChannelMonitor for channel {}", log_funding_info!(monitor));
724 let update_res = monitor.update_monitor(update, &self.broadcaster, &*self.fee_estimator, &self.logger);
725 if update_res.is_err() {
726 log_error!(self.logger, "Failed to update ChannelMonitor for channel {}.", log_funding_info!(monitor));
728 // Even if updating the monitor returns an error, the monitor's state will
729 // still be changed. So, persist the updated monitor despite the error.
730 let update_id = MonitorUpdateId::from_monitor_update(update);
731 let mut pending_monitor_updates = monitor_state.pending_monitor_updates.lock().unwrap();
732 let persist_res = self.persister.update_persisted_channel(funding_txo, Some(update), monitor, update_id);
734 ChannelMonitorUpdateStatus::InProgress => {
735 pending_monitor_updates.push(update_id);
736 log_debug!(self.logger, "Persistence of ChannelMonitorUpdate for channel {} in progress", log_funding_info!(monitor));
738 ChannelMonitorUpdateStatus::Completed => {
739 log_debug!(self.logger, "Persistence of ChannelMonitorUpdate for channel {} completed", log_funding_info!(monitor));
742 if update_res.is_err() {
743 ChannelMonitorUpdateStatus::InProgress
744 } else if monitor_state.channel_perm_failed.load(Ordering::Acquire) {
745 ChannelMonitorUpdateStatus::InProgress
753 fn release_pending_monitor_events(&self) -> Vec<(OutPoint, Vec<MonitorEvent>, Option<PublicKey>)> {
754 let mut pending_monitor_events = self.pending_monitor_events.lock().unwrap().split_off(0);
755 for monitor_state in self.monitors.read().unwrap().values() {
756 let is_pending_monitor_update = monitor_state.has_pending_chainsync_updates(&monitor_state.pending_monitor_updates.lock().unwrap());
757 if is_pending_monitor_update &&
758 monitor_state.last_chain_persist_height.load(Ordering::Acquire) + LATENCY_GRACE_PERIOD_BLOCKS as usize
759 > self.highest_chain_height.load(Ordering::Acquire)
761 log_debug!(self.logger, "A Channel Monitor sync is still in progress, refusing to provide monitor events!");
763 if monitor_state.channel_perm_failed.load(Ordering::Acquire) {
764 // If a `UpdateOrigin::ChainSync` persistence failed with `PermanantFailure`,
765 // we don't really know if the latest `ChannelMonitor` state is on disk or not.
766 // We're supposed to hold monitor updates until the latest state is on disk to
767 // avoid duplicate events, but the user told us persistence is screw-y and may
768 // not complete. We can't hold events forever because we may learn some payment
769 // preimage, so instead we just log and hope the user complied with the
770 // `PermanentFailure` requirements of having at least the local-disk copy
772 log_info!(self.logger, "A Channel Monitor sync returned PermanentFailure. Returning monitor events but duplicate events may appear after reload!");
774 if is_pending_monitor_update {
775 log_error!(self.logger, "A ChannelMonitor sync took longer than {} blocks to complete.", LATENCY_GRACE_PERIOD_BLOCKS);
776 log_error!(self.logger, " To avoid funds-loss, we are allowing monitor updates to be released.");
777 log_error!(self.logger, " This may cause duplicate payment events to be generated.");
779 let monitor_events = monitor_state.monitor.get_and_clear_pending_monitor_events();
780 if monitor_events.len() > 0 {
781 let monitor_outpoint = monitor_state.monitor.get_funding_txo().0;
782 let counterparty_node_id = monitor_state.monitor.get_counterparty_node_id();
783 pending_monitor_events.push((monitor_outpoint, monitor_events, counterparty_node_id));
787 pending_monitor_events
791 impl<ChannelSigner: WriteableEcdsaChannelSigner, C: Deref, T: Deref, F: Deref, L: Deref, P: Deref> events::EventsProvider for ChainMonitor<ChannelSigner, C, T, F, L, P>
792 where C::Target: chain::Filter,
793 T::Target: BroadcasterInterface,
794 F::Target: FeeEstimator,
796 P::Target: Persist<ChannelSigner>,
798 /// Processes [`SpendableOutputs`] events produced from each [`ChannelMonitor`] upon maturity.
800 /// For channels featuring anchor outputs, this method will also process [`BumpTransaction`]
801 /// events produced from each [`ChannelMonitor`] while there is a balance to claim onchain
802 /// within each channel. As the confirmation of a commitment transaction may be critical to the
803 /// safety of funds, we recommend invoking this every 30 seconds, or lower if running in an
804 /// environment with spotty connections, like on mobile.
806 /// An [`EventHandler`] may safely call back to the provider, though this shouldn't be needed in
807 /// order to handle these events.
809 /// [`SpendableOutputs`]: events::Event::SpendableOutputs
810 /// [`BumpTransaction`]: events::Event::BumpTransaction
811 fn process_pending_events<H: Deref>(&self, handler: H) where H::Target: EventHandler {
812 for monitor_state in self.monitors.read().unwrap().values() {
813 monitor_state.monitor.process_pending_events(&handler);
820 use crate::check_added_monitors;
821 use crate::{expect_payment_claimed, expect_payment_path_successful, get_event_msg};
822 use crate::{get_htlc_update_msgs, get_local_commitment_txn, get_revoke_commit_msgs, get_route_and_payment_hash, unwrap_send_err};
823 use crate::chain::{ChannelMonitorUpdateStatus, Confirm, Watch};
824 use crate::chain::channelmonitor::LATENCY_GRACE_PERIOD_BLOCKS;
825 use crate::events::{Event, MessageSendEvent, MessageSendEventsProvider};
826 use crate::ln::channelmanager::{PaymentSendFailure, PaymentId, RecipientOnionFields};
827 use crate::ln::functional_test_utils::*;
828 use crate::ln::msgs::ChannelMessageHandler;
829 use crate::util::errors::APIError;
832 fn test_async_ooo_offchain_updates() {
833 // Test that if we have multiple offchain updates being persisted and they complete
834 // out-of-order, the ChainMonitor waits until all have completed before informing the
836 let chanmon_cfgs = create_chanmon_cfgs(2);
837 let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
838 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
839 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
840 create_announced_chan_between_nodes(&nodes, 0, 1);
842 // Route two payments to be claimed at the same time.
843 let (payment_preimage_1, payment_hash_1, ..) = route_payment(&nodes[0], &[&nodes[1]], 1_000_000);
844 let (payment_preimage_2, payment_hash_2, ..) = route_payment(&nodes[0], &[&nodes[1]], 1_000_000);
846 chanmon_cfgs[1].persister.offchain_monitor_updates.lock().unwrap().clear();
847 chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
848 chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
850 nodes[1].node.claim_funds(payment_preimage_1);
851 check_added_monitors!(nodes[1], 1);
852 nodes[1].node.claim_funds(payment_preimage_2);
853 check_added_monitors!(nodes[1], 1);
855 let persistences = chanmon_cfgs[1].persister.offchain_monitor_updates.lock().unwrap().clone();
856 assert_eq!(persistences.len(), 1);
857 let (funding_txo, updates) = persistences.iter().next().unwrap();
858 assert_eq!(updates.len(), 2);
860 // Note that updates is a HashMap so the ordering here is actually random. This shouldn't
861 // fail either way but if it fails intermittently it's depending on the ordering of updates.
862 let mut update_iter = updates.iter();
863 let next_update = update_iter.next().unwrap().clone();
864 // Should contain next_update when pending updates listed.
865 #[cfg(not(c_bindings))]
866 assert!(nodes[1].chain_monitor.chain_monitor.list_pending_monitor_updates().get(funding_txo)
867 .unwrap().contains(&next_update));
869 assert!(nodes[1].chain_monitor.chain_monitor.list_pending_monitor_updates().iter()
870 .find(|(txo, _)| txo == funding_txo).unwrap().1.contains(&next_update));
871 nodes[1].chain_monitor.chain_monitor.channel_monitor_updated(*funding_txo, next_update.clone()).unwrap();
872 // Should not contain the previously pending next_update when pending updates listed.
873 #[cfg(not(c_bindings))]
874 assert!(!nodes[1].chain_monitor.chain_monitor.list_pending_monitor_updates().get(funding_txo)
875 .unwrap().contains(&next_update));
877 assert!(!nodes[1].chain_monitor.chain_monitor.list_pending_monitor_updates().iter()
878 .find(|(txo, _)| txo == funding_txo).unwrap().1.contains(&next_update));
879 assert!(nodes[1].chain_monitor.release_pending_monitor_events().is_empty());
880 assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
881 assert!(nodes[1].node.get_and_clear_pending_events().is_empty());
882 nodes[1].chain_monitor.chain_monitor.channel_monitor_updated(*funding_txo, update_iter.next().unwrap().clone()).unwrap();
884 let claim_events = nodes[1].node.get_and_clear_pending_events();
885 assert_eq!(claim_events.len(), 2);
886 match claim_events[0] {
887 Event::PaymentClaimed { ref payment_hash, amount_msat: 1_000_000, .. } => {
888 assert_eq!(payment_hash_1, *payment_hash);
890 _ => panic!("Unexpected event"),
892 match claim_events[1] {
893 Event::PaymentClaimed { ref payment_hash, amount_msat: 1_000_000, .. } => {
894 assert_eq!(payment_hash_2, *payment_hash);
896 _ => panic!("Unexpected event"),
899 // Now manually walk the commitment signed dance - because we claimed two payments
900 // back-to-back it doesn't fit into the neat walk commitment_signed_dance does.
902 let updates = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
903 nodes[0].node.handle_update_fulfill_htlc(&nodes[1].node.get_our_node_id(), &updates.update_fulfill_htlcs[0]);
904 expect_payment_sent(&nodes[0], payment_preimage_1, None, false, false);
905 nodes[0].node.handle_commitment_signed(&nodes[1].node.get_our_node_id(), &updates.commitment_signed);
906 check_added_monitors!(nodes[0], 1);
907 let (as_first_raa, as_first_update) = get_revoke_commit_msgs!(nodes[0], nodes[1].node.get_our_node_id());
909 nodes[1].node.handle_revoke_and_ack(&nodes[0].node.get_our_node_id(), &as_first_raa);
910 check_added_monitors!(nodes[1], 1);
911 let bs_second_updates = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
912 nodes[1].node.handle_commitment_signed(&nodes[0].node.get_our_node_id(), &as_first_update);
913 check_added_monitors!(nodes[1], 1);
914 let bs_first_raa = get_event_msg!(nodes[1], MessageSendEvent::SendRevokeAndACK, nodes[0].node.get_our_node_id());
916 nodes[0].node.handle_update_fulfill_htlc(&nodes[1].node.get_our_node_id(), &bs_second_updates.update_fulfill_htlcs[0]);
917 expect_payment_sent(&nodes[0], payment_preimage_2, None, false, false);
918 nodes[0].node.handle_commitment_signed(&nodes[1].node.get_our_node_id(), &bs_second_updates.commitment_signed);
919 check_added_monitors!(nodes[0], 1);
920 nodes[0].node.handle_revoke_and_ack(&nodes[1].node.get_our_node_id(), &bs_first_raa);
921 expect_payment_path_successful!(nodes[0]);
922 check_added_monitors!(nodes[0], 1);
923 let (as_second_raa, as_second_update) = get_revoke_commit_msgs!(nodes[0], nodes[1].node.get_our_node_id());
925 nodes[1].node.handle_revoke_and_ack(&nodes[0].node.get_our_node_id(), &as_second_raa);
926 check_added_monitors!(nodes[1], 1);
927 nodes[1].node.handle_commitment_signed(&nodes[0].node.get_our_node_id(), &as_second_update);
928 check_added_monitors!(nodes[1], 1);
929 let bs_second_raa = get_event_msg!(nodes[1], MessageSendEvent::SendRevokeAndACK, nodes[0].node.get_our_node_id());
931 nodes[0].node.handle_revoke_and_ack(&nodes[1].node.get_our_node_id(), &bs_second_raa);
932 expect_payment_path_successful!(nodes[0]);
933 check_added_monitors!(nodes[0], 1);
936 fn do_chainsync_pauses_events(block_timeout: bool) {
937 // When a chainsync monitor update occurs, any MonitorUpdates should be held before being
938 // passed upstream to a `ChannelManager` via `Watch::release_pending_monitor_events`. This
939 // tests that behavior, as well as some ways it might go wrong.
940 let chanmon_cfgs = create_chanmon_cfgs(2);
941 let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
942 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
943 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
944 let channel = create_announced_chan_between_nodes(&nodes, 0, 1);
946 // Get a route for later and rebalance the channel somewhat
947 send_payment(&nodes[0], &[&nodes[1]], 10_000_000);
948 let (route, second_payment_hash, _, second_payment_secret) = get_route_and_payment_hash!(nodes[0], nodes[1], 100_000);
950 // First route a payment that we will claim on chain and give the recipient the preimage.
951 let (payment_preimage, payment_hash, ..) = route_payment(&nodes[0], &[&nodes[1]], 1_000_000);
952 nodes[1].node.claim_funds(payment_preimage);
953 expect_payment_claimed!(nodes[1], payment_hash, 1_000_000);
954 nodes[1].node.get_and_clear_pending_msg_events();
955 check_added_monitors!(nodes[1], 1);
956 let remote_txn = get_local_commitment_txn!(nodes[1], channel.2);
957 assert_eq!(remote_txn.len(), 2);
959 // Temp-fail the block connection which will hold the channel-closed event
960 chanmon_cfgs[0].persister.chain_sync_monitor_persistences.lock().unwrap().clear();
961 chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
963 // Connect B's commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
964 // channel is now closed, but the ChannelManager doesn't know that yet.
965 let new_header = create_dummy_header(nodes[0].best_block_info().0, 0);
966 nodes[0].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
967 &[(0, &remote_txn[0]), (1, &remote_txn[1])], nodes[0].best_block_info().1 + 1);
968 assert!(nodes[0].chain_monitor.release_pending_monitor_events().is_empty());
969 nodes[0].chain_monitor.chain_monitor.best_block_updated(&new_header, nodes[0].best_block_info().1 + 1);
970 assert!(nodes[0].chain_monitor.release_pending_monitor_events().is_empty());
972 // If the ChannelManager tries to update the channel, however, the ChainMonitor will pass
973 // the update through to the ChannelMonitor which will refuse it (as the channel is closed).
974 chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
975 unwrap_send_err!(nodes[0].node.send_payment_with_route(&route, second_payment_hash,
976 RecipientOnionFields::secret_only(second_payment_secret), PaymentId(second_payment_hash.0)
977 ), false, APIError::MonitorUpdateInProgress, {});
978 check_added_monitors!(nodes[0], 1);
980 // However, as the ChainMonitor is still waiting for the original persistence to complete,
981 // it won't yet release the MonitorEvents.
982 assert!(nodes[0].chain_monitor.release_pending_monitor_events().is_empty());
985 // After three blocks, pending MontiorEvents should be released either way.
986 let latest_header = create_dummy_header(nodes[0].best_block_info().0, 0);
987 nodes[0].chain_monitor.chain_monitor.best_block_updated(&latest_header, nodes[0].best_block_info().1 + LATENCY_GRACE_PERIOD_BLOCKS);
989 let persistences = chanmon_cfgs[0].persister.chain_sync_monitor_persistences.lock().unwrap().clone();
990 for (funding_outpoint, update_ids) in persistences {
991 for update_id in update_ids {
992 nodes[0].chain_monitor.chain_monitor.channel_monitor_updated(funding_outpoint, update_id).unwrap();
997 expect_payment_sent(&nodes[0], payment_preimage, None, true, false);
1001 fn chainsync_pauses_events() {
1002 do_chainsync_pauses_events(false);
1003 do_chainsync_pauses_events(true);