//! events. The remote server would make use of [`ChainMonitor`] for block processing and for
//! servicing [`ChannelMonitor`] updates from the client.
-use bitcoin::blockdata::block::{Block, BlockHeader};
-use bitcoin::hash_types::Txid;
-
-use chain;
-use chain::{Filter, WatchedOutput};
-use chain::chaininterface::{BroadcasterInterface, FeeEstimator};
-use chain::channelmonitor;
-use chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateErr, MonitorEvent, Persist, TransactionOutputs};
-use chain::transaction::{OutPoint, TransactionData};
-use chain::keysinterface::Sign;
-use util::logger::Logger;
-use util::events;
-use util::events::EventHandler;
-
-use prelude::*;
-use std::sync::RwLock;
+use bitcoin::blockdata::block::BlockHeader;
+use bitcoin::hash_types::{Txid, BlockHash};
+
+use crate::chain;
+use crate::chain::{ChannelMonitorUpdateStatus, Filter, WatchedOutput};
+use crate::chain::chaininterface::{BroadcasterInterface, FeeEstimator};
+use crate::chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, Balance, MonitorEvent, TransactionOutputs, LATENCY_GRACE_PERIOD_BLOCKS};
+use crate::chain::transaction::{OutPoint, TransactionData};
+use crate::sign::WriteableEcdsaChannelSigner;
+use crate::events;
+use crate::events::{Event, EventHandler};
+use crate::util::atomic_counter::AtomicCounter;
+use crate::util::logger::Logger;
+use crate::util::errors::APIError;
+use crate::util::wakers::{Future, Notifier};
+use crate::ln::channelmanager::ChannelDetails;
+
+use crate::prelude::*;
+use crate::sync::{RwLock, RwLockReadGuard, Mutex, MutexGuard};
+use core::iter::FromIterator;
use core::ops::Deref;
+use core::sync::atomic::{AtomicUsize, Ordering};
+use bitcoin::secp256k1::PublicKey;
+
+#[derive(Debug, Clone, Copy, Hash, PartialEq, Eq)]
+/// A specific update's ID stored in a `MonitorUpdateId`, separated out to make the contents
+/// entirely opaque.
+enum UpdateOrigin {
+ /// An update that was generated by the `ChannelManager` (via our `chain::Watch`
+ /// implementation). This corresponds to an actual [`ChannelMonitorUpdate::update_id`] field
+ /// and [`ChannelMonitor::get_latest_update_id`].
+ OffChain(u64),
+ /// An update that was generated during blockchain processing. The ID here is specific to the
+ /// generating [`ChainMonitor`] and does *not* correspond to any on-disk IDs.
+ ChainSync(u64),
+}
+
+/// An opaque identifier describing a specific [`Persist`] method call.
+#[derive(Debug, Clone, Copy, Hash, PartialEq, Eq)]
+pub struct MonitorUpdateId {
+ contents: UpdateOrigin,
+}
+
+impl MonitorUpdateId {
+ pub(crate) fn from_monitor_update(update: &ChannelMonitorUpdate) -> Self {
+ Self { contents: UpdateOrigin::OffChain(update.update_id) }
+ }
+ pub(crate) fn from_new_monitor<ChannelSigner: WriteableEcdsaChannelSigner>(monitor: &ChannelMonitor<ChannelSigner>) -> Self {
+ Self { contents: UpdateOrigin::OffChain(monitor.get_latest_update_id()) }
+ }
+}
+
+/// `Persist` defines behavior for persisting channel monitors: this could mean
+/// writing once to disk, and/or uploading to one or more backup services.
+///
+/// Persistence can happen in one of two ways - synchronously completing before the trait method
+/// calls return or asynchronously in the background.
+///
+/// # For those implementing synchronous persistence
+///
+/// * If persistence completes fully (including any relevant `fsync()` calls), the implementation
+/// should return [`ChannelMonitorUpdateStatus::Completed`], indicating normal channel operation
+/// should continue.
+///
+/// * If persistence fails for some reason, implementations should consider returning
+/// [`ChannelMonitorUpdateStatus::InProgress`] and retry all pending persistence operations in
+/// the background with [`ChainMonitor::list_pending_monitor_updates`] and
+/// [`ChainMonitor::get_monitor`].
+///
+/// Once a full [`ChannelMonitor`] has been persisted, all pending updates for that channel can
+/// be marked as complete via [`ChainMonitor::channel_monitor_updated`].
+///
+/// If at some point no further progress can be made towards persisting the pending updates, the
+/// node should simply shut down.
+///
+/// * If the persistence has failed and cannot be retried further (e.g. because of some timeout),
+/// [`ChannelMonitorUpdateStatus::UnrecoverableError`] can be used, though this will result in
+/// an immediate panic and future operations in LDK generally failing.
+///
+/// # For those implementing asynchronous persistence
+///
+/// All calls should generally spawn a background task and immediately return
+/// [`ChannelMonitorUpdateStatus::InProgress`]. Once the update completes,
+/// [`ChainMonitor::channel_monitor_updated`] should be called with the corresponding
+/// [`MonitorUpdateId`].
+///
+/// Note that unlike the direct [`chain::Watch`] interface,
+/// [`ChainMonitor::channel_monitor_updated`] must be called once for *each* update which occurs.
+///
+/// If at some point no further progress can be made towards persisting a pending update, the node
+/// should simply shut down.
+///
+/// # Using remote watchtowers
+///
+/// Watchtowers may be updated as a part of an implementation of this trait, utilizing the async
+/// update process described above while the watchtower is being updated. The following methods are
+/// provided for bulding transactions for a watchtower:
+/// [`ChannelMonitor::initial_counterparty_commitment_tx`],
+/// [`ChannelMonitor::counterparty_commitment_txs_from_update`],
+/// [`ChannelMonitor::sign_to_local_justice_tx`], [`TrustedCommitmentTransaction::revokeable_output_index`],
+/// [`TrustedCommitmentTransaction::build_to_local_justice_tx`].
+///
+/// [`TrustedCommitmentTransaction::revokeable_output_index`]: crate::ln::chan_utils::TrustedCommitmentTransaction::revokeable_output_index
+/// [`TrustedCommitmentTransaction::build_to_local_justice_tx`]: crate::ln::chan_utils::TrustedCommitmentTransaction::build_to_local_justice_tx
+pub trait Persist<ChannelSigner: WriteableEcdsaChannelSigner> {
+ /// Persist a new channel's data in response to a [`chain::Watch::watch_channel`] call. This is
+ /// called by [`ChannelManager`] for new channels, or may be called directly, e.g. on startup.
+ ///
+ /// The data can be stored any way you want, but the identifier provided by LDK is the
+ /// channel's outpoint (and it is up to you to maintain a correct mapping between the outpoint
+ /// and the stored channel data). Note that you **must** persist every new monitor to disk.
+ ///
+ /// The `update_id` is used to identify this call to [`ChainMonitor::channel_monitor_updated`],
+ /// if you return [`ChannelMonitorUpdateStatus::InProgress`].
+ ///
+ /// See [`Writeable::write`] on [`ChannelMonitor`] for writing out a `ChannelMonitor`
+ /// and [`ChannelMonitorUpdateStatus`] for requirements when returning errors.
+ ///
+ /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
+ /// [`Writeable::write`]: crate::util::ser::Writeable::write
+ fn persist_new_channel(&self, channel_id: OutPoint, data: &ChannelMonitor<ChannelSigner>, update_id: MonitorUpdateId) -> ChannelMonitorUpdateStatus;
+
+ /// Update one channel's data. The provided [`ChannelMonitor`] has already applied the given
+ /// update.
+ ///
+ /// Note that on every update, you **must** persist either the [`ChannelMonitorUpdate`] or the
+ /// updated monitor itself to disk/backups. See the [`Persist`] trait documentation for more
+ /// details.
+ ///
+ /// During blockchain synchronization operations, this may be called with no
+ /// [`ChannelMonitorUpdate`], in which case the full [`ChannelMonitor`] needs to be persisted.
+ /// Note that after the full [`ChannelMonitor`] is persisted any previous
+ /// [`ChannelMonitorUpdate`]s which were persisted should be discarded - they can no longer be
+ /// applied to the persisted [`ChannelMonitor`] as they were already applied.
+ ///
+ /// If an implementer chooses to persist the updates only, they need to make
+ /// sure that all the updates are applied to the `ChannelMonitors` *before*
+ /// the set of channel monitors is given to the `ChannelManager`
+ /// deserialization routine. See [`ChannelMonitor::update_monitor`] for
+ /// applying a monitor update to a monitor. If full `ChannelMonitors` are
+ /// persisted, then there is no need to persist individual updates.
+ ///
+ /// Note that there could be a performance tradeoff between persisting complete
+ /// channel monitors on every update vs. persisting only updates and applying
+ /// them in batches. The size of each monitor grows `O(number of state updates)`
+ /// whereas updates are small and `O(1)`.
+ ///
+ /// The `update_id` is used to identify this call to [`ChainMonitor::channel_monitor_updated`],
+ /// if you return [`ChannelMonitorUpdateStatus::InProgress`].
+ ///
+ /// See [`Writeable::write`] on [`ChannelMonitor`] for writing out a `ChannelMonitor`,
+ /// [`Writeable::write`] on [`ChannelMonitorUpdate`] for writing out an update, and
+ /// [`ChannelMonitorUpdateStatus`] for requirements when returning errors.
+ ///
+ /// [`Writeable::write`]: crate::util::ser::Writeable::write
+ fn update_persisted_channel(&self, channel_id: OutPoint, update: Option<&ChannelMonitorUpdate>, data: &ChannelMonitor<ChannelSigner>, update_id: MonitorUpdateId) -> ChannelMonitorUpdateStatus;
+}
+
+struct MonitorHolder<ChannelSigner: WriteableEcdsaChannelSigner> {
+ monitor: ChannelMonitor<ChannelSigner>,
+ /// The full set of pending monitor updates for this Channel.
+ ///
+ /// Note that this lock must be held during updates to prevent a race where we call
+ /// update_persisted_channel, the user returns a
+ /// [`ChannelMonitorUpdateStatus::InProgress`], and then calls channel_monitor_updated
+ /// immediately, racing our insertion of the pending update into the contained Vec.
+ ///
+ /// Beyond the synchronization of updates themselves, we cannot handle user events until after
+ /// any chain updates have been stored on disk. Thus, we scan this list when returning updates
+ /// to the ChannelManager, refusing to return any updates for a ChannelMonitor which is still
+ /// being persisted fully to disk after a chain update.
+ ///
+ /// This avoids the possibility of handling, e.g. an on-chain claim, generating a claim monitor
+ /// event, resulting in the relevant ChannelManager generating a PaymentSent event and dropping
+ /// the pending payment entry, and then reloading before the monitor is persisted, resulting in
+ /// the ChannelManager re-adding the same payment entry, before the same block is replayed,
+ /// resulting in a duplicate PaymentSent event.
+ pending_monitor_updates: Mutex<Vec<MonitorUpdateId>>,
+ /// The last block height at which no [`UpdateOrigin::ChainSync`] monitor updates were present
+ /// in `pending_monitor_updates`.
+ /// If it's been more than [`LATENCY_GRACE_PERIOD_BLOCKS`] since we started waiting on a chain
+ /// sync event, we let monitor events return to `ChannelManager` because we cannot hold them up
+ /// forever or we'll end up with HTLC preimages waiting to feed back into an upstream channel
+ /// forever, risking funds loss.
+ last_chain_persist_height: AtomicUsize,
+}
+
+impl<ChannelSigner: WriteableEcdsaChannelSigner> MonitorHolder<ChannelSigner> {
+ fn has_pending_offchain_updates(&self, pending_monitor_updates_lock: &MutexGuard<Vec<MonitorUpdateId>>) -> bool {
+ pending_monitor_updates_lock.iter().any(|update_id|
+ if let UpdateOrigin::OffChain(_) = update_id.contents { true } else { false })
+ }
+ fn has_pending_chainsync_updates(&self, pending_monitor_updates_lock: &MutexGuard<Vec<MonitorUpdateId>>) -> bool {
+ pending_monitor_updates_lock.iter().any(|update_id|
+ if let UpdateOrigin::ChainSync(_) = update_id.contents { true } else { false })
+ }
+}
+
+/// A read-only reference to a current ChannelMonitor.
+///
+/// Note that this holds a mutex in [`ChainMonitor`] and may block other events until it is
+/// released.
+pub struct LockedChannelMonitor<'a, ChannelSigner: WriteableEcdsaChannelSigner> {
+ lock: RwLockReadGuard<'a, HashMap<OutPoint, MonitorHolder<ChannelSigner>>>,
+ funding_txo: OutPoint,
+}
+
+impl<ChannelSigner: WriteableEcdsaChannelSigner> Deref for LockedChannelMonitor<'_, ChannelSigner> {
+ type Target = ChannelMonitor<ChannelSigner>;
+ fn deref(&self) -> &ChannelMonitor<ChannelSigner> {
+ &self.lock.get(&self.funding_txo).expect("Checked at construction").monitor
+ }
+}
/// An implementation of [`chain::Watch`] for monitoring channels.
///
/// or used independently to monitor channels remotely. See the [module-level documentation] for
/// details.
///
+/// Note that `ChainMonitor` should regularly trigger rebroadcasts/fee bumps of pending claims from
+/// a force-closed channel. This is crucial in preventing certain classes of pinning attacks,
+/// detecting substantial mempool feerate changes between blocks, and ensuring reliability if
+/// broadcasting fails. We recommend invoking this every 30 seconds, or lower if running in an
+/// environment with spotty connections, like on mobile.
+///
/// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
/// [module-level documentation]: crate::chain::chainmonitor
-pub struct ChainMonitor<ChannelSigner: Sign, C: Deref, T: Deref, F: Deref, L: Deref, P: Deref>
+/// [`rebroadcast_pending_claims`]: Self::rebroadcast_pending_claims
+pub struct ChainMonitor<ChannelSigner: WriteableEcdsaChannelSigner, C: Deref, T: Deref, F: Deref, L: Deref, P: Deref>
where C::Target: chain::Filter,
T::Target: BroadcasterInterface,
F::Target: FeeEstimator,
L::Target: Logger,
- P::Target: channelmonitor::Persist<ChannelSigner>,
+ P::Target: Persist<ChannelSigner>,
{
- /// The monitors
- pub monitors: RwLock<HashMap<OutPoint, ChannelMonitor<ChannelSigner>>>,
+ monitors: RwLock<HashMap<OutPoint, MonitorHolder<ChannelSigner>>>,
+ /// When we generate a [`MonitorUpdateId`] for a chain-event monitor persistence, we need a
+ /// unique ID, which we calculate by simply getting the next value from this counter. Note that
+ /// the ID is never persisted so it's ok that they reset on restart.
+ sync_persistence_id: AtomicCounter,
chain_source: Option<C>,
broadcaster: T,
logger: L,
fee_estimator: F,
persister: P,
+ /// "User-provided" (ie persistence-completion/-failed) [`MonitorEvent`]s. These came directly
+ /// from the user and not from a [`ChannelMonitor`].
+ pending_monitor_events: Mutex<Vec<(OutPoint, Vec<MonitorEvent>, Option<PublicKey>)>>,
+ /// The best block height seen, used as a proxy for the passage of time.
+ highest_chain_height: AtomicUsize,
+
+ event_notifier: Notifier,
}
-impl<ChannelSigner: Sign, C: Deref, T: Deref, F: Deref, L: Deref, P: Deref> ChainMonitor<ChannelSigner, C, T, F, L, P>
+impl<ChannelSigner: WriteableEcdsaChannelSigner, C: Deref, T: Deref, F: Deref, L: Deref, P: Deref> ChainMonitor<ChannelSigner, C, T, F, L, P>
where C::Target: chain::Filter,
T::Target: BroadcasterInterface,
F::Target: FeeEstimator,
L::Target: Logger,
- P::Target: channelmonitor::Persist<ChannelSigner>,
+ P::Target: Persist<ChannelSigner>,
{
/// Dispatches to per-channel monitors, which are responsible for updating their on-chain view
/// of a channel and reacting accordingly based on transactions in the given chain data. See
/// calls must not exclude any transactions matching the new outputs nor any in-block
/// descendants of such transactions. It is not necessary to re-fetch the block to obtain
/// updated `txdata`.
- fn process_chain_data<FN>(&self, header: &BlockHeader, txdata: &TransactionData, process: FN)
+ ///
+ /// Calls which represent a new blockchain tip height should set `best_height`.
+ fn process_chain_data<FN>(&self, header: &BlockHeader, best_height: Option<u32>, txdata: &TransactionData, process: FN)
where
FN: Fn(&ChannelMonitor<ChannelSigner>, &TransactionData) -> Vec<TransactionOutputs>
{
- let mut dependent_txdata = Vec::new();
- let monitors = self.monitors.read().unwrap();
- for monitor in monitors.values() {
- let mut txn_outputs = process(monitor, txdata);
-
- // Register any new outputs with the chain source for filtering, storing any dependent
- // transactions from within the block that previously had not been included in txdata.
- if let Some(ref chain_source) = self.chain_source {
- let block_hash = header.block_hash();
- for (txid, mut outputs) in txn_outputs.drain(..) {
- for (idx, output) in outputs.drain(..) {
- // Register any new outputs with the chain source for filtering and recurse
- // if it indicates that there are dependent transactions within the block
- // that had not been previously included in txdata.
- let output = WatchedOutput {
- block_hash: Some(block_hash),
- outpoint: OutPoint { txid, index: idx as u16 },
- script_pubkey: output.script_pubkey,
- };
- if let Some(tx) = chain_source.register_output(output) {
- dependent_txdata.push(tx);
- }
- }
+ let err_str = "ChannelMonitor[Update] persistence failed unrecoverably. This indicates we cannot continue normal operation and must shut down.";
+ let funding_outpoints: HashSet<OutPoint> = HashSet::from_iter(self.monitors.read().unwrap().keys().cloned());
+ for funding_outpoint in funding_outpoints.iter() {
+ let monitor_lock = self.monitors.read().unwrap();
+ if let Some(monitor_state) = monitor_lock.get(funding_outpoint) {
+ if self.update_monitor_with_chain_data(header, best_height, txdata, &process, funding_outpoint, &monitor_state).is_err() {
+ // Take the monitors lock for writing so that we poison it and any future
+ // operations going forward fail immediately.
+ core::mem::drop(monitor_state);
+ core::mem::drop(monitor_lock);
+ let _poison = self.monitors.write().unwrap();
+ log_error!(self.logger, "{}", err_str);
+ panic!("{}", err_str);
+ }
+ }
+ }
+
+ // do some followup cleanup if any funding outpoints were added in between iterations
+ let monitor_states = self.monitors.write().unwrap();
+ for (funding_outpoint, monitor_state) in monitor_states.iter() {
+ if !funding_outpoints.contains(funding_outpoint) {
+ if self.update_monitor_with_chain_data(header, best_height, txdata, &process, funding_outpoint, &monitor_state).is_err() {
+ log_error!(self.logger, "{}", err_str);
+ panic!("{}", err_str);
}
}
}
- // Recursively call for any dependent transactions that were identified by the chain source.
- if !dependent_txdata.is_empty() {
- dependent_txdata.sort_unstable_by_key(|(index, _tx)| *index);
- dependent_txdata.dedup_by_key(|(index, _tx)| *index);
- let txdata: Vec<_> = dependent_txdata.iter().map(|(index, tx)| (*index, tx)).collect();
- self.process_chain_data(header, &txdata, process);
+ if let Some(height) = best_height {
+ // If the best block height is being updated, update highest_chain_height under the
+ // monitors write lock.
+ let old_height = self.highest_chain_height.load(Ordering::Acquire);
+ let new_height = height as usize;
+ if new_height > old_height {
+ self.highest_chain_height.store(new_height, Ordering::Release);
+ }
+ }
+ }
+
+ 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>
+ ) -> Result<(), ()> where FN: Fn(&ChannelMonitor<ChannelSigner>, &TransactionData) -> Vec<TransactionOutputs> {
+ let monitor = &monitor_state.monitor;
+ let mut txn_outputs;
+ {
+ txn_outputs = process(monitor, txdata);
+ let update_id = MonitorUpdateId {
+ contents: UpdateOrigin::ChainSync(self.sync_persistence_id.get_increment()),
+ };
+ let mut pending_monitor_updates = monitor_state.pending_monitor_updates.lock().unwrap();
+ if let Some(height) = best_height {
+ if !monitor_state.has_pending_chainsync_updates(&pending_monitor_updates) {
+ // If there are not ChainSync persists awaiting completion, go ahead and
+ // set last_chain_persist_height here - we wouldn't want the first
+ // InProgress to always immediately be considered "overly delayed".
+ monitor_state.last_chain_persist_height.store(height as usize, Ordering::Release);
+ }
+ }
+
+ log_trace!(self.logger, "Syncing Channel Monitor for channel {}", log_funding_info!(monitor));
+ match self.persister.update_persisted_channel(*funding_outpoint, None, monitor, update_id) {
+ ChannelMonitorUpdateStatus::Completed =>
+ log_trace!(self.logger, "Finished syncing Channel Monitor for channel {}", log_funding_info!(monitor)),
+ ChannelMonitorUpdateStatus::InProgress => {
+ log_debug!(self.logger, "Channel Monitor sync for channel {} in progress, holding events until completion!", log_funding_info!(monitor));
+ pending_monitor_updates.push(update_id);
+ },
+ ChannelMonitorUpdateStatus::UnrecoverableError => {
+ return Err(());
+ },
+ }
+ }
+
+ // Register any new outputs with the chain source for filtering, storing any dependent
+ // transactions from within the block that previously had not been included in txdata.
+ if let Some(ref chain_source) = self.chain_source {
+ let block_hash = header.block_hash();
+ for (txid, mut outputs) in txn_outputs.drain(..) {
+ for (idx, output) in outputs.drain(..) {
+ // Register any new outputs with the chain source for filtering
+ let output = WatchedOutput {
+ block_hash: Some(block_hash),
+ outpoint: OutPoint { txid, index: idx as u16 },
+ script_pubkey: output.script_pubkey,
+ };
+ chain_source.register_output(output)
+ }
+ }
}
+ Ok(())
}
/// Creates a new `ChainMonitor` used to watch on-chain activity pertaining to channels.
pub fn new(chain_source: Option<C>, broadcaster: T, logger: L, feeest: F, persister: P) -> Self {
Self {
monitors: RwLock::new(HashMap::new()),
+ sync_persistence_id: AtomicCounter::new(),
chain_source,
broadcaster,
logger,
fee_estimator: feeest,
persister,
+ pending_monitor_events: Mutex::new(Vec::new()),
+ highest_chain_height: AtomicUsize::new(0),
+ event_notifier: Notifier::new(),
+ }
+ }
+
+ /// Gets the balances in the contained [`ChannelMonitor`]s which are claimable on-chain or
+ /// claims which are awaiting confirmation.
+ ///
+ /// Includes the balances from each [`ChannelMonitor`] *except* those included in
+ /// `ignored_channels`.
+ ///
+ /// See [`ChannelMonitor::get_claimable_balances`] for more details on the exact criteria for
+ /// inclusion in the return value.
+ pub fn get_claimable_balances(&self, ignored_channels: &[&ChannelDetails]) -> Vec<Balance> {
+ let mut ret = Vec::new();
+ let monitor_states = self.monitors.read().unwrap();
+ for (_, monitor_state) in monitor_states.iter().filter(|(funding_outpoint, _)| {
+ for chan in ignored_channels {
+ if chan.funding_txo.as_ref() == Some(funding_outpoint) {
+ return false;
+ }
+ }
+ true
+ }) {
+ ret.append(&mut monitor_state.monitor.get_claimable_balances());
+ }
+ ret
+ }
+
+ /// Gets the [`LockedChannelMonitor`] for a given funding outpoint, returning an `Err` if no
+ /// such [`ChannelMonitor`] is currently being monitored for.
+ ///
+ /// Note that the result holds a mutex over our monitor set, and should not be held
+ /// indefinitely.
+ pub fn get_monitor(&self, funding_txo: OutPoint) -> Result<LockedChannelMonitor<'_, ChannelSigner>, ()> {
+ let lock = self.monitors.read().unwrap();
+ if lock.get(&funding_txo).is_some() {
+ Ok(LockedChannelMonitor { lock, funding_txo })
+ } else {
+ Err(())
+ }
+ }
+
+ /// Lists the funding outpoint of each [`ChannelMonitor`] being monitored.
+ ///
+ /// Note that [`ChannelMonitor`]s are not removed when a channel is closed as they are always
+ /// monitoring for on-chain state resolutions.
+ pub fn list_monitors(&self) -> Vec<OutPoint> {
+ self.monitors.read().unwrap().keys().map(|outpoint| *outpoint).collect()
+ }
+
+ #[cfg(not(c_bindings))]
+ /// Lists the pending updates for each [`ChannelMonitor`] (by `OutPoint` being monitored).
+ pub fn list_pending_monitor_updates(&self) -> HashMap<OutPoint, Vec<MonitorUpdateId>> {
+ self.monitors.read().unwrap().iter().map(|(outpoint, holder)| {
+ (*outpoint, holder.pending_monitor_updates.lock().unwrap().clone())
+ }).collect()
+ }
+
+ #[cfg(c_bindings)]
+ /// Lists the pending updates for each [`ChannelMonitor`] (by `OutPoint` being monitored).
+ pub fn list_pending_monitor_updates(&self) -> Vec<(OutPoint, Vec<MonitorUpdateId>)> {
+ self.monitors.read().unwrap().iter().map(|(outpoint, holder)| {
+ (*outpoint, holder.pending_monitor_updates.lock().unwrap().clone())
+ }).collect()
+ }
+
+
+ #[cfg(test)]
+ pub fn remove_monitor(&self, funding_txo: &OutPoint) -> ChannelMonitor<ChannelSigner> {
+ self.monitors.write().unwrap().remove(funding_txo).unwrap().monitor
+ }
+
+ /// Indicates the persistence of a [`ChannelMonitor`] has completed after
+ /// [`ChannelMonitorUpdateStatus::InProgress`] was returned from an update operation.
+ ///
+ /// Thus, the anticipated use is, at a high level:
+ /// 1) This [`ChainMonitor`] calls [`Persist::update_persisted_channel`] which stores the
+ /// update to disk and begins updating any remote (e.g. watchtower/backup) copies,
+ /// returning [`ChannelMonitorUpdateStatus::InProgress`],
+ /// 2) once all remote copies are updated, you call this function with the
+ /// `completed_update_id` that completed, and once all pending updates have completed the
+ /// channel will be re-enabled.
+ // Note that we re-enable only after `UpdateOrigin::OffChain` updates complete, we don't
+ // care about `UpdateOrigin::ChainSync` updates for the channel state being updated. We
+ // only care about `UpdateOrigin::ChainSync` for returning `MonitorEvent`s.
+ ///
+ /// Returns an [`APIError::APIMisuseError`] if `funding_txo` does not match any currently
+ /// registered [`ChannelMonitor`]s.
+ pub fn channel_monitor_updated(&self, funding_txo: OutPoint, completed_update_id: MonitorUpdateId) -> Result<(), APIError> {
+ let monitors = self.monitors.read().unwrap();
+ let monitor_data = if let Some(mon) = monitors.get(&funding_txo) { mon } else {
+ return Err(APIError::APIMisuseError { err: format!("No ChannelMonitor matching funding outpoint {:?} found", funding_txo) });
+ };
+ let mut pending_monitor_updates = monitor_data.pending_monitor_updates.lock().unwrap();
+ pending_monitor_updates.retain(|update_id| *update_id != completed_update_id);
+
+ match completed_update_id {
+ MonitorUpdateId { contents: UpdateOrigin::OffChain(_) } => {
+ // Note that we only check for `UpdateOrigin::OffChain` failures here - if
+ // we're being told that a `UpdateOrigin::OffChain` monitor update completed,
+ // we only care about ensuring we don't tell the `ChannelManager` to restore
+ // the channel to normal operation until all `UpdateOrigin::OffChain` updates
+ // complete.
+ // If there's some `UpdateOrigin::ChainSync` update still pending that's okay
+ // - we can still update our channel state, just as long as we don't return
+ // `MonitorEvent`s from the monitor back to the `ChannelManager` until they
+ // complete.
+ let monitor_is_pending_updates = monitor_data.has_pending_offchain_updates(&pending_monitor_updates);
+ if monitor_is_pending_updates {
+ // If there are still monitor updates pending, we cannot yet construct a
+ // Completed event.
+ return Ok(());
+ }
+ self.pending_monitor_events.lock().unwrap().push((funding_txo, vec![MonitorEvent::Completed {
+ funding_txo,
+ monitor_update_id: monitor_data.monitor.get_latest_update_id(),
+ }], monitor_data.monitor.get_counterparty_node_id()));
+ },
+ MonitorUpdateId { contents: UpdateOrigin::ChainSync(_) } => {
+ if !monitor_data.has_pending_chainsync_updates(&pending_monitor_updates) {
+ monitor_data.last_chain_persist_height.store(self.highest_chain_height.load(Ordering::Acquire), Ordering::Release);
+ // The next time release_pending_monitor_events is called, any events for this
+ // ChannelMonitor will be returned.
+ }
+ },
}
+ self.event_notifier.notify();
+ Ok(())
}
- #[cfg(any(test, feature = "fuzztarget", feature = "_test_utils"))]
+ /// This wrapper avoids having to update some of our tests for now as they assume the direct
+ /// chain::Watch API wherein we mark a monitor fully-updated by just calling
+ /// channel_monitor_updated once with the highest ID.
+ #[cfg(any(test, fuzzing))]
+ pub fn force_channel_monitor_updated(&self, funding_txo: OutPoint, monitor_update_id: u64) {
+ let monitors = self.monitors.read().unwrap();
+ let counterparty_node_id = monitors.get(&funding_txo).and_then(|m| m.monitor.get_counterparty_node_id());
+ self.pending_monitor_events.lock().unwrap().push((funding_txo, vec![MonitorEvent::Completed {
+ funding_txo,
+ monitor_update_id,
+ }], counterparty_node_id));
+ self.event_notifier.notify();
+ }
+
+ #[cfg(any(test, feature = "_test_utils"))]
pub fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
- use util::events::EventsProvider;
+ use crate::events::EventsProvider;
let events = core::cell::RefCell::new(Vec::new());
- let event_handler = |event| events.borrow_mut().push(event);
+ let event_handler = |event: events::Event| events.borrow_mut().push(event);
self.process_pending_events(&event_handler);
events.into_inner()
}
+
+ /// Processes any events asynchronously in the order they were generated since the last call
+ /// using the given event handler.
+ ///
+ /// See the trait-level documentation of [`EventsProvider`] for requirements.
+ ///
+ /// [`EventsProvider`]: crate::events::EventsProvider
+ pub async fn process_pending_events_async<Future: core::future::Future, H: Fn(Event) -> Future>(
+ &self, handler: H
+ ) {
+ // Sadly we can't hold the monitors read lock through an async call. Thus we have to do a
+ // crazy dance to process a monitor's events then only remove them once we've done so.
+ let mons_to_process = self.monitors.read().unwrap().keys().cloned().collect::<Vec<_>>();
+ for funding_txo in mons_to_process {
+ let mut ev;
+ super::channelmonitor::process_events_body!(
+ self.monitors.read().unwrap().get(&funding_txo).map(|m| &m.monitor), ev, handler(ev).await);
+ }
+ }
+
+ /// Gets a [`Future`] that completes when an event is available either via
+ /// [`chain::Watch::release_pending_monitor_events`] or
+ /// [`EventsProvider::process_pending_events`].
+ ///
+ /// Note that callbacks registered on the [`Future`] MUST NOT call back into this
+ /// [`ChainMonitor`] and should instead register actions to be taken later.
+ ///
+ /// [`EventsProvider::process_pending_events`]: crate::events::EventsProvider::process_pending_events
+ pub fn get_update_future(&self) -> Future {
+ self.event_notifier.get_future()
+ }
+
+ /// Triggers rebroadcasts/fee-bumps of pending claims from a force-closed channel. This is
+ /// crucial in preventing certain classes of pinning attacks, detecting substantial mempool
+ /// feerate changes between blocks, and ensuring reliability if broadcasting fails. We recommend
+ /// invoking this every 30 seconds, or lower if running in an environment with spotty
+ /// connections, like on mobile.
+ pub fn rebroadcast_pending_claims(&self) {
+ let monitors = self.monitors.read().unwrap();
+ for (_, monitor_holder) in &*monitors {
+ monitor_holder.monitor.rebroadcast_pending_claims(
+ &*self.broadcaster, &*self.fee_estimator, &*self.logger
+ )
+ }
+ }
}
-impl<ChannelSigner: Sign, C: Deref, T: Deref, F: Deref, L: Deref, P: Deref>
+impl<ChannelSigner: WriteableEcdsaChannelSigner, C: Deref, T: Deref, F: Deref, L: Deref, P: Deref>
chain::Listen for ChainMonitor<ChannelSigner, C, T, F, L, P>
where
C::Target: chain::Filter,
T::Target: BroadcasterInterface,
F::Target: FeeEstimator,
L::Target: Logger,
- P::Target: channelmonitor::Persist<ChannelSigner>,
+ P::Target: Persist<ChannelSigner>,
{
- fn block_connected(&self, block: &Block, height: u32) {
- let header = &block.header;
- let txdata: Vec<_> = block.txdata.iter().enumerate().collect();
- self.process_chain_data(header, &txdata, |monitor, txdata| {
+ fn filtered_block_connected(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
+ log_debug!(self.logger, "New best block {} at height {} provided via block_connected", header.block_hash(), height);
+ self.process_chain_data(header, Some(height), &txdata, |monitor, txdata| {
monitor.block_connected(
header, txdata, height, &*self.broadcaster, &*self.fee_estimator, &*self.logger)
});
}
fn block_disconnected(&self, header: &BlockHeader, height: u32) {
- let monitors = self.monitors.read().unwrap();
- for monitor in monitors.values() {
- monitor.block_disconnected(
+ let monitor_states = self.monitors.read().unwrap();
+ log_debug!(self.logger, "Latest block {} at height {} removed via block_disconnected", header.block_hash(), height);
+ for monitor_state in monitor_states.values() {
+ monitor_state.monitor.block_disconnected(
header, height, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
}
}
}
-impl<ChannelSigner: Sign, C: Deref, T: Deref, F: Deref, L: Deref, P: Deref>
+impl<ChannelSigner: WriteableEcdsaChannelSigner, C: Deref, T: Deref, F: Deref, L: Deref, P: Deref>
chain::Confirm for ChainMonitor<ChannelSigner, C, T, F, L, P>
where
C::Target: chain::Filter,
T::Target: BroadcasterInterface,
F::Target: FeeEstimator,
L::Target: Logger,
- P::Target: channelmonitor::Persist<ChannelSigner>,
+ P::Target: Persist<ChannelSigner>,
{
fn transactions_confirmed(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
- self.process_chain_data(header, txdata, |monitor, txdata| {
+ log_debug!(self.logger, "{} provided transactions confirmed at height {} in block {}", txdata.len(), height, header.block_hash());
+ self.process_chain_data(header, None, txdata, |monitor, txdata| {
monitor.transactions_confirmed(
header, txdata, height, &*self.broadcaster, &*self.fee_estimator, &*self.logger)
});
}
fn transaction_unconfirmed(&self, txid: &Txid) {
- let monitors = self.monitors.read().unwrap();
- for monitor in monitors.values() {
- monitor.transaction_unconfirmed(txid, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
+ log_debug!(self.logger, "Transaction {} reorganized out of chain", txid);
+ let monitor_states = self.monitors.read().unwrap();
+ for monitor_state in monitor_states.values() {
+ monitor_state.monitor.transaction_unconfirmed(txid, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
}
}
fn best_block_updated(&self, header: &BlockHeader, height: u32) {
- self.process_chain_data(header, &[], |monitor, txdata| {
+ log_debug!(self.logger, "New best block {} at height {} provided via best_block_updated", header.block_hash(), height);
+ self.process_chain_data(header, Some(height), &[], |monitor, txdata| {
// While in practice there shouldn't be any recursive calls when given empty txdata,
// it's still possible if a chain::Filter implementation returns a transaction.
debug_assert!(txdata.is_empty());
});
}
- fn get_relevant_txids(&self) -> Vec<Txid> {
+ fn get_relevant_txids(&self) -> Vec<(Txid, Option<BlockHash>)> {
let mut txids = Vec::new();
- let monitors = self.monitors.read().unwrap();
- for monitor in monitors.values() {
- txids.append(&mut monitor.get_relevant_txids());
+ let monitor_states = self.monitors.read().unwrap();
+ for monitor_state in monitor_states.values() {
+ txids.append(&mut monitor_state.monitor.get_relevant_txids());
}
txids.sort_unstable();
}
}
-impl<ChannelSigner: Sign, C: Deref , T: Deref , F: Deref , L: Deref , P: Deref >
+impl<ChannelSigner: WriteableEcdsaChannelSigner, C: Deref , T: Deref , F: Deref , L: Deref , P: Deref >
chain::Watch<ChannelSigner> for ChainMonitor<ChannelSigner, C, T, F, L, P>
where C::Target: chain::Filter,
T::Target: BroadcasterInterface,
F::Target: FeeEstimator,
L::Target: Logger,
- P::Target: channelmonitor::Persist<ChannelSigner>,
+ P::Target: Persist<ChannelSigner>,
{
- /// Adds the monitor that watches the channel referred to by the given outpoint.
- ///
- /// Calls back to [`chain::Filter`] with the funding transaction and outputs to watch.
- ///
- /// Note that we persist the given `ChannelMonitor` while holding the `ChainMonitor`
- /// monitors lock.
- fn watch_channel(&self, funding_outpoint: OutPoint, monitor: ChannelMonitor<ChannelSigner>) -> Result<(), ChannelMonitorUpdateErr> {
+ fn watch_channel(&self, funding_outpoint: OutPoint, monitor: ChannelMonitor<ChannelSigner>) -> Result<ChannelMonitorUpdateStatus, ()> {
let mut monitors = self.monitors.write().unwrap();
let entry = match monitors.entry(funding_outpoint) {
hash_map::Entry::Occupied(_) => {
log_error!(self.logger, "Failed to add new channel data: channel monitor for given outpoint is already present");
- return Err(ChannelMonitorUpdateErr::PermanentFailure)},
+ return Err(());
+ },
hash_map::Entry::Vacant(e) => e,
};
- if let Err(e) = self.persister.persist_new_channel(funding_outpoint, &monitor) {
- log_error!(self.logger, "Failed to persist new channel data");
- return Err(e);
+ log_trace!(self.logger, "Got new ChannelMonitor for channel {}", log_funding_info!(monitor));
+ let update_id = MonitorUpdateId::from_new_monitor(&monitor);
+ let mut pending_monitor_updates = Vec::new();
+ let persist_res = self.persister.persist_new_channel(funding_outpoint, &monitor, update_id);
+ match persist_res {
+ ChannelMonitorUpdateStatus::InProgress => {
+ log_info!(self.logger, "Persistence of new ChannelMonitor for channel {} in progress", log_funding_info!(monitor));
+ pending_monitor_updates.push(update_id);
+ },
+ ChannelMonitorUpdateStatus::Completed => {
+ log_info!(self.logger, "Persistence of new ChannelMonitor for channel {} completed", log_funding_info!(monitor));
+ },
+ ChannelMonitorUpdateStatus::UnrecoverableError => {
+ let err_str = "ChannelMonitor[Update] persistence failed unrecoverably. This indicates we cannot continue normal operation and must shut down.";
+ log_error!(self.logger, "{}", err_str);
+ panic!("{}", err_str);
+ },
}
- {
- let funding_txo = monitor.get_funding_txo();
- log_trace!(self.logger, "Got new Channel Monitor for channel {}", log_bytes!(funding_txo.0.to_channel_id()[..]));
-
- if let Some(ref chain_source) = self.chain_source {
- monitor.load_outputs_to_watch(chain_source);
- }
+ if let Some(ref chain_source) = self.chain_source {
+ monitor.load_outputs_to_watch(chain_source);
}
- entry.insert(monitor);
- Ok(())
+ entry.insert(MonitorHolder {
+ monitor,
+ pending_monitor_updates: Mutex::new(pending_monitor_updates),
+ last_chain_persist_height: AtomicUsize::new(self.highest_chain_height.load(Ordering::Acquire)),
+ });
+ Ok(persist_res)
}
- /// Note that we persist the given `ChannelMonitor` update while holding the
- /// `ChainMonitor` monitors lock.
- fn update_channel(&self, funding_txo: OutPoint, update: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr> {
+ fn update_channel(&self, funding_txo: OutPoint, update: &ChannelMonitorUpdate) -> ChannelMonitorUpdateStatus {
// Update the monitor that watches the channel referred to by the given outpoint.
let monitors = self.monitors.read().unwrap();
- match monitors.get(&funding_txo) {
+ let ret = match monitors.get(&funding_txo) {
None => {
log_error!(self.logger, "Failed to update channel monitor: no such monitor registered");
// We should never ever trigger this from within ChannelManager. Technically a
// user could use this object with some proxying in between which makes this
// possible, but in tests and fuzzing, this should be a panic.
- #[cfg(any(test, feature = "fuzztarget"))]
+ #[cfg(debug_assertions)]
panic!("ChannelManager generated a channel update for a channel that was not yet registered!");
- #[cfg(not(any(test, feature = "fuzztarget")))]
- Err(ChannelMonitorUpdateErr::PermanentFailure)
+ #[cfg(not(debug_assertions))]
+ ChannelMonitorUpdateStatus::InProgress
},
- Some(monitor) => {
- log_trace!(self.logger, "Updating Channel Monitor for channel {}", log_funding_info!(monitor));
- let update_res = monitor.update_monitor(&update, &self.broadcaster, &self.fee_estimator, &self.logger);
- if let Err(e) = &update_res {
- log_error!(self.logger, "Failed to update channel monitor: {:?}", e);
+ Some(monitor_state) => {
+ let monitor = &monitor_state.monitor;
+ log_trace!(self.logger, "Updating ChannelMonitor for channel {}", log_funding_info!(monitor));
+ let update_res = monitor.update_monitor(update, &self.broadcaster, &*self.fee_estimator, &self.logger);
+ if update_res.is_err() {
+ log_error!(self.logger, "Failed to update ChannelMonitor for channel {}.", log_funding_info!(monitor));
}
// Even if updating the monitor returns an error, the monitor's state will
// still be changed. So, persist the updated monitor despite the error.
- let persist_res = self.persister.update_persisted_channel(funding_txo, &update, monitor);
- if let Err(ref e) = persist_res {
- log_error!(self.logger, "Failed to persist channel monitor update: {:?}", e);
+ let update_id = MonitorUpdateId::from_monitor_update(update);
+ let mut pending_monitor_updates = monitor_state.pending_monitor_updates.lock().unwrap();
+ let persist_res = self.persister.update_persisted_channel(funding_txo, Some(update), monitor, update_id);
+ match persist_res {
+ ChannelMonitorUpdateStatus::InProgress => {
+ pending_monitor_updates.push(update_id);
+ log_debug!(self.logger, "Persistence of ChannelMonitorUpdate for channel {} in progress", log_funding_info!(monitor));
+ },
+ ChannelMonitorUpdateStatus::Completed => {
+ log_debug!(self.logger, "Persistence of ChannelMonitorUpdate for channel {} completed", log_funding_info!(monitor));
+ },
+ ChannelMonitorUpdateStatus::UnrecoverableError => { /* we'll panic in a moment */ },
}
if update_res.is_err() {
- Err(ChannelMonitorUpdateErr::PermanentFailure)
+ ChannelMonitorUpdateStatus::InProgress
} else {
persist_res
}
}
+ };
+ if let ChannelMonitorUpdateStatus::UnrecoverableError = ret {
+ // Take the monitors lock for writing so that we poison it and any future
+ // operations going forward fail immediately.
+ core::mem::drop(monitors);
+ let _poison = self.monitors.write().unwrap();
+ let err_str = "ChannelMonitor[Update] persistence failed unrecoverably. This indicates we cannot continue normal operation and must shut down.";
+ log_error!(self.logger, "{}", err_str);
+ panic!("{}", err_str);
}
+ ret
}
- fn release_pending_monitor_events(&self) -> Vec<MonitorEvent> {
- let mut pending_monitor_events = Vec::new();
- for monitor in self.monitors.read().unwrap().values() {
- pending_monitor_events.append(&mut monitor.get_and_clear_pending_monitor_events());
+ fn release_pending_monitor_events(&self) -> Vec<(OutPoint, Vec<MonitorEvent>, Option<PublicKey>)> {
+ let mut pending_monitor_events = self.pending_monitor_events.lock().unwrap().split_off(0);
+ for monitor_state in self.monitors.read().unwrap().values() {
+ let is_pending_monitor_update = monitor_state.has_pending_chainsync_updates(&monitor_state.pending_monitor_updates.lock().unwrap());
+ if is_pending_monitor_update &&
+ monitor_state.last_chain_persist_height.load(Ordering::Acquire) + LATENCY_GRACE_PERIOD_BLOCKS as usize
+ > self.highest_chain_height.load(Ordering::Acquire)
+ {
+ log_debug!(self.logger, "A Channel Monitor sync is still in progress, refusing to provide monitor events!");
+ } else {
+ if is_pending_monitor_update {
+ log_error!(self.logger, "A ChannelMonitor sync took longer than {} blocks to complete.", LATENCY_GRACE_PERIOD_BLOCKS);
+ log_error!(self.logger, " To avoid funds-loss, we are allowing monitor updates to be released.");
+ log_error!(self.logger, " This may cause duplicate payment events to be generated.");
+ }
+ let monitor_events = monitor_state.monitor.get_and_clear_pending_monitor_events();
+ if monitor_events.len() > 0 {
+ let monitor_outpoint = monitor_state.monitor.get_funding_txo().0;
+ let counterparty_node_id = monitor_state.monitor.get_counterparty_node_id();
+ pending_monitor_events.push((monitor_outpoint, monitor_events, counterparty_node_id));
+ }
+ }
}
pending_monitor_events
}
}
-impl<ChannelSigner: Sign, C: Deref, T: Deref, F: Deref, L: Deref, P: Deref> events::EventsProvider for ChainMonitor<ChannelSigner, C, T, F, L, P>
+impl<ChannelSigner: WriteableEcdsaChannelSigner, C: Deref, T: Deref, F: Deref, L: Deref, P: Deref> events::EventsProvider for ChainMonitor<ChannelSigner, C, T, F, L, P>
where C::Target: chain::Filter,
T::Target: BroadcasterInterface,
F::Target: FeeEstimator,
L::Target: Logger,
- P::Target: channelmonitor::Persist<ChannelSigner>,
+ P::Target: Persist<ChannelSigner>,
{
/// Processes [`SpendableOutputs`] events produced from each [`ChannelMonitor`] upon maturity.
///
+ /// For channels featuring anchor outputs, this method will also process [`BumpTransaction`]
+ /// events produced from each [`ChannelMonitor`] while there is a balance to claim onchain
+ /// within each channel. As the confirmation of a commitment transaction may be critical to the
+ /// safety of funds, we recommend invoking this every 30 seconds, or lower if running in an
+ /// environment with spotty connections, like on mobile.
+ ///
/// An [`EventHandler`] may safely call back to the provider, though this shouldn't be needed in
/// order to handle these events.
///
/// [`SpendableOutputs`]: events::Event::SpendableOutputs
+ /// [`BumpTransaction`]: events::Event::BumpTransaction
fn process_pending_events<H: Deref>(&self, handler: H) where H::Target: EventHandler {
- let mut pending_events = Vec::new();
- for monitor in self.monitors.read().unwrap().values() {
- pending_events.append(&mut monitor.get_and_clear_pending_events());
- }
- for event in pending_events.drain(..) {
- handler.handle_event(event);
+ for monitor_state in self.monitors.read().unwrap().values() {
+ monitor_state.monitor.process_pending_events(&handler);
}
}
}
#[cfg(test)]
mod tests {
- use ::{check_added_monitors, get_local_commitment_txn};
- use ln::features::InitFeatures;
- use ln::functional_test_utils::*;
- use util::events::MessageSendEventsProvider;
- use util::test_utils::{OnRegisterOutput, TxOutReference};
-
- /// Tests that in-block dependent transactions are processed by `block_connected` when not
- /// included in `txdata` but returned by [`chain::Filter::register_output`]. For instance,
- /// a (non-anchor) commitment transaction's HTLC output may be spent in the same block as the
- /// commitment transaction itself. An Electrum client may filter the commitment transaction but
- /// needs to return the HTLC transaction so it can be processed.
+ use crate::check_added_monitors;
+ use crate::{expect_payment_claimed, expect_payment_path_successful, get_event_msg};
+ use crate::{get_htlc_update_msgs, get_local_commitment_txn, get_revoke_commit_msgs, get_route_and_payment_hash, unwrap_send_err};
+ use crate::chain::{ChannelMonitorUpdateStatus, Confirm, Watch};
+ use crate::chain::channelmonitor::LATENCY_GRACE_PERIOD_BLOCKS;
+ use crate::events::{Event, MessageSendEvent, MessageSendEventsProvider};
+ use crate::ln::channelmanager::{PaymentSendFailure, PaymentId, RecipientOnionFields};
+ use crate::ln::functional_test_utils::*;
+ use crate::ln::msgs::ChannelMessageHandler;
+ use crate::util::errors::APIError;
+
#[test]
- fn connect_block_checks_dependent_transactions() {
+ fn test_async_ooo_offchain_updates() {
+ // Test that if we have multiple offchain updates being persisted and they complete
+ // out-of-order, the ChainMonitor waits until all have completed before informing the
+ // ChannelManager.
let chanmon_cfgs = create_chanmon_cfgs(2);
let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
- let channel = create_announced_chan_between_nodes(
- &nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
+ create_announced_chan_between_nodes(&nodes, 0, 1);
- // Send a payment, saving nodes[0]'s revoked commitment and HTLC-Timeout transactions.
- let (commitment_tx, htlc_tx) = {
- let payment_preimage = route_payment(&nodes[0], &vec!(&nodes[1])[..], 5_000_000).0;
- let mut txn = get_local_commitment_txn!(nodes[0], channel.2);
- claim_payment(&nodes[0], &vec!(&nodes[1])[..], payment_preimage);
+ // Route two payments to be claimed at the same time.
+ let (payment_preimage_1, payment_hash_1, ..) = route_payment(&nodes[0], &[&nodes[1]], 1_000_000);
+ let (payment_preimage_2, payment_hash_2, ..) = route_payment(&nodes[0], &[&nodes[1]], 1_000_000);
- assert_eq!(txn.len(), 2);
- (txn.remove(0), txn.remove(0))
- };
+ chanmon_cfgs[1].persister.offchain_monitor_updates.lock().unwrap().clear();
+ chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
+ chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
+
+ nodes[1].node.claim_funds(payment_preimage_1);
+ check_added_monitors!(nodes[1], 1);
+ nodes[1].node.claim_funds(payment_preimage_2);
+ check_added_monitors!(nodes[1], 1);
+
+ let persistences = chanmon_cfgs[1].persister.offchain_monitor_updates.lock().unwrap().clone();
+ assert_eq!(persistences.len(), 1);
+ let (funding_txo, updates) = persistences.iter().next().unwrap();
+ assert_eq!(updates.len(), 2);
+
+ // Note that updates is a HashMap so the ordering here is actually random. This shouldn't
+ // fail either way but if it fails intermittently it's depending on the ordering of updates.
+ let mut update_iter = updates.iter();
+ let next_update = update_iter.next().unwrap().clone();
+ // Should contain next_update when pending updates listed.
+ #[cfg(not(c_bindings))]
+ assert!(nodes[1].chain_monitor.chain_monitor.list_pending_monitor_updates().get(funding_txo)
+ .unwrap().contains(&next_update));
+ #[cfg(c_bindings)]
+ assert!(nodes[1].chain_monitor.chain_monitor.list_pending_monitor_updates().iter()
+ .find(|(txo, _)| txo == funding_txo).unwrap().1.contains(&next_update));
+ nodes[1].chain_monitor.chain_monitor.channel_monitor_updated(*funding_txo, next_update.clone()).unwrap();
+ // Should not contain the previously pending next_update when pending updates listed.
+ #[cfg(not(c_bindings))]
+ assert!(!nodes[1].chain_monitor.chain_monitor.list_pending_monitor_updates().get(funding_txo)
+ .unwrap().contains(&next_update));
+ #[cfg(c_bindings)]
+ assert!(!nodes[1].chain_monitor.chain_monitor.list_pending_monitor_updates().iter()
+ .find(|(txo, _)| txo == funding_txo).unwrap().1.contains(&next_update));
+ assert!(nodes[1].chain_monitor.release_pending_monitor_events().is_empty());
+ assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
+ assert!(nodes[1].node.get_and_clear_pending_events().is_empty());
+ nodes[1].chain_monitor.chain_monitor.channel_monitor_updated(*funding_txo, update_iter.next().unwrap().clone()).unwrap();
+
+ let claim_events = nodes[1].node.get_and_clear_pending_events();
+ assert_eq!(claim_events.len(), 2);
+ match claim_events[0] {
+ Event::PaymentClaimed { ref payment_hash, amount_msat: 1_000_000, .. } => {
+ assert_eq!(payment_hash_1, *payment_hash);
+ },
+ _ => panic!("Unexpected event"),
+ }
+ match claim_events[1] {
+ Event::PaymentClaimed { ref payment_hash, amount_msat: 1_000_000, .. } => {
+ assert_eq!(payment_hash_2, *payment_hash);
+ },
+ _ => panic!("Unexpected event"),
+ }
- // Set expectations on nodes[1]'s chain source to return dependent transactions.
- let htlc_output = TxOutReference(commitment_tx.clone(), 0);
- let to_local_output = TxOutReference(commitment_tx.clone(), 1);
- let htlc_timeout_output = TxOutReference(htlc_tx.clone(), 0);
- nodes[1].chain_source
- .expect(OnRegisterOutput { with: htlc_output, returns: Some((1, htlc_tx)) })
- .expect(OnRegisterOutput { with: to_local_output, returns: None })
- .expect(OnRegisterOutput { with: htlc_timeout_output, returns: None });
+ // Now manually walk the commitment signed dance - because we claimed two payments
+ // back-to-back it doesn't fit into the neat walk commitment_signed_dance does.
- // Notify nodes[1] that nodes[0]'s revoked commitment transaction was mined. The chain
- // source should return the dependent HTLC transaction when the HTLC output is registered.
- mine_transaction(&nodes[1], &commitment_tx);
+ let updates = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
+ nodes[0].node.handle_update_fulfill_htlc(&nodes[1].node.get_our_node_id(), &updates.update_fulfill_htlcs[0]);
+ expect_payment_sent(&nodes[0], payment_preimage_1, None, false, false);
+ nodes[0].node.handle_commitment_signed(&nodes[1].node.get_our_node_id(), &updates.commitment_signed);
+ check_added_monitors!(nodes[0], 1);
+ let (as_first_raa, as_first_update) = get_revoke_commit_msgs!(nodes[0], nodes[1].node.get_our_node_id());
- // Clean up so uninteresting assertions don't fail.
+ nodes[1].node.handle_revoke_and_ack(&nodes[0].node.get_our_node_id(), &as_first_raa);
check_added_monitors!(nodes[1], 1);
+ let bs_second_updates = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
+ nodes[1].node.handle_commitment_signed(&nodes[0].node.get_our_node_id(), &as_first_update);
+ check_added_monitors!(nodes[1], 1);
+ let bs_first_raa = get_event_msg!(nodes[1], MessageSendEvent::SendRevokeAndACK, nodes[0].node.get_our_node_id());
+
+ nodes[0].node.handle_update_fulfill_htlc(&nodes[1].node.get_our_node_id(), &bs_second_updates.update_fulfill_htlcs[0]);
+ expect_payment_sent(&nodes[0], payment_preimage_2, None, false, false);
+ nodes[0].node.handle_commitment_signed(&nodes[1].node.get_our_node_id(), &bs_second_updates.commitment_signed);
+ check_added_monitors!(nodes[0], 1);
+ nodes[0].node.handle_revoke_and_ack(&nodes[1].node.get_our_node_id(), &bs_first_raa);
+ expect_payment_path_successful!(nodes[0]);
+ check_added_monitors!(nodes[0], 1);
+ let (as_second_raa, as_second_update) = get_revoke_commit_msgs!(nodes[0], nodes[1].node.get_our_node_id());
+
+ nodes[1].node.handle_revoke_and_ack(&nodes[0].node.get_our_node_id(), &as_second_raa);
+ check_added_monitors!(nodes[1], 1);
+ nodes[1].node.handle_commitment_signed(&nodes[0].node.get_our_node_id(), &as_second_update);
+ check_added_monitors!(nodes[1], 1);
+ let bs_second_raa = get_event_msg!(nodes[1], MessageSendEvent::SendRevokeAndACK, nodes[0].node.get_our_node_id());
+
+ nodes[0].node.handle_revoke_and_ack(&nodes[1].node.get_our_node_id(), &bs_second_raa);
+ expect_payment_path_successful!(nodes[0]);
+ check_added_monitors!(nodes[0], 1);
+ }
+
+ fn do_chainsync_pauses_events(block_timeout: bool) {
+ // When a chainsync monitor update occurs, any MonitorUpdates should be held before being
+ // passed upstream to a `ChannelManager` via `Watch::release_pending_monitor_events`. This
+ // tests that behavior, as well as some ways it might go wrong.
+ let chanmon_cfgs = create_chanmon_cfgs(2);
+ let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
+ let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
+ let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
+ let channel = create_announced_chan_between_nodes(&nodes, 0, 1);
+
+ // Get a route for later and rebalance the channel somewhat
+ send_payment(&nodes[0], &[&nodes[1]], 10_000_000);
+ let (route, second_payment_hash, _, second_payment_secret) = get_route_and_payment_hash!(nodes[0], nodes[1], 100_000);
+
+ // First route a payment that we will claim on chain and give the recipient the preimage.
+ let (payment_preimage, payment_hash, ..) = route_payment(&nodes[0], &[&nodes[1]], 1_000_000);
+ nodes[1].node.claim_funds(payment_preimage);
+ expect_payment_claimed!(nodes[1], payment_hash, 1_000_000);
nodes[1].node.get_and_clear_pending_msg_events();
- nodes[1].node.get_and_clear_pending_events();
+ check_added_monitors!(nodes[1], 1);
+ let remote_txn = get_local_commitment_txn!(nodes[1], channel.2);
+ assert_eq!(remote_txn.len(), 2);
+
+ // Temp-fail the block connection which will hold the channel-closed event
+ chanmon_cfgs[0].persister.chain_sync_monitor_persistences.lock().unwrap().clear();
+ chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
+
+ // Connect B's commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
+ // channel is now closed, but the ChannelManager doesn't know that yet.
+ let new_header = create_dummy_header(nodes[0].best_block_info().0, 0);
+ nodes[0].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
+ &[(0, &remote_txn[0]), (1, &remote_txn[1])], nodes[0].best_block_info().1 + 1);
+ assert!(nodes[0].chain_monitor.release_pending_monitor_events().is_empty());
+ nodes[0].chain_monitor.chain_monitor.best_block_updated(&new_header, nodes[0].best_block_info().1 + 1);
+ assert!(nodes[0].chain_monitor.release_pending_monitor_events().is_empty());
+
+ // If the ChannelManager tries to update the channel, however, the ChainMonitor will pass
+ // the update through to the ChannelMonitor which will refuse it (as the channel is closed).
+ chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::Completed);
+ unwrap_send_err!(nodes[0].node.send_payment_with_route(&route, second_payment_hash,
+ RecipientOnionFields::secret_only(second_payment_secret), PaymentId(second_payment_hash.0)
+ ), false, APIError::MonitorUpdateInProgress, {});
+ check_added_monitors!(nodes[0], 1);
+
+ // However, as the ChainMonitor is still waiting for the original persistence to complete,
+ // it won't yet release the MonitorEvents.
+ assert!(nodes[0].chain_monitor.release_pending_monitor_events().is_empty());
+
+ if block_timeout {
+ // After three blocks, pending MontiorEvents should be released either way.
+ let latest_header = create_dummy_header(nodes[0].best_block_info().0, 0);
+ nodes[0].chain_monitor.chain_monitor.best_block_updated(&latest_header, nodes[0].best_block_info().1 + LATENCY_GRACE_PERIOD_BLOCKS);
+ } else {
+ let persistences = chanmon_cfgs[0].persister.chain_sync_monitor_persistences.lock().unwrap().clone();
+ for (funding_outpoint, update_ids) in persistences {
+ for update_id in update_ids {
+ nodes[0].chain_monitor.chain_monitor.channel_monitor_updated(funding_outpoint, update_id).unwrap();
+ }
+ }
+ }
+
+ expect_payment_sent(&nodes[0], payment_preimage, None, true, false);
+ }
+
+ #[test]
+ fn chainsync_pauses_events() {
+ do_chainsync_pauses_events(false);
+ do_chainsync_pauses_events(true);
+ }
+
+ #[test]
+ #[cfg(feature = "std")]
+ fn update_during_chainsync_poisons_channel() {
+ let chanmon_cfgs = create_chanmon_cfgs(2);
+ let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
+ let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
+ let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
+ create_announced_chan_between_nodes(&nodes, 0, 1);
+
+ chanmon_cfgs[0].persister.chain_sync_monitor_persistences.lock().unwrap().clear();
+ chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::UnrecoverableError);
+
+ assert!(std::panic::catch_unwind(|| {
+ // Returning an UnrecoverableError should always panic immediately
+ connect_blocks(&nodes[0], 1);
+ }).is_err());
+ assert!(std::panic::catch_unwind(|| {
+ // ...and also poison our locks causing later use to panic as well
+ core::mem::drop(nodes);
+ }).is_err());
}
}