//! 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::blockdata::block::BlockHeader;
use bitcoin::hash_types::Txid;
use chain;
use chain::{ChannelMonitorUpdateErr, Filter, WatchedOutput};
use chain::chaininterface::{BroadcasterInterface, FeeEstimator};
-use chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, Balance, MonitorEvent, TransactionOutputs};
+use chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, Balance, MonitorEvent, TransactionOutputs, LATENCY_GRACE_PERIOD_BLOCKS};
use chain::transaction::{OutPoint, TransactionData};
use chain::keysinterface::Sign;
+use util::atomic_counter::AtomicCounter;
use util::logger::Logger;
+use util::errors::APIError;
use util::events;
use util::events::EventHandler;
use ln::channelmanager::ChannelDetails;
use prelude::*;
-use sync::{RwLock, RwLockReadGuard, Mutex};
+use sync::{RwLock, RwLockReadGuard, Mutex, MutexGuard};
use core::ops::Deref;
+use core::sync::atomic::{AtomicBool, AtomicUsize, Ordering};
+
+#[derive(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(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: Sign>(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.
///
-/// Note that for every new monitor, you **must** persist the new `ChannelMonitor`
-/// to disk/backups. And, on every update, you **must** persist either the
-/// `ChannelMonitorUpdate` or the updated monitor itself. Otherwise, there is risk
-/// of situations such as revoking a transaction, then crashing before this
-/// revocation can be persisted, then unintentionally broadcasting a revoked
-/// transaction and losing money. This is a risk because previous channel states
-/// are toxic, so it's important that whatever channel state is persisted is
-/// kept up-to-date.
+/// Each method can return three possible values:
+/// * If persistence (including any relevant `fsync()` calls) happens immediately, the
+/// implementation should return `Ok(())`, indicating normal channel operation should continue.
+/// * If persistence happens asynchronously, implementations should first ensure the
+/// [`ChannelMonitor`] or [`ChannelMonitorUpdate`] are written durably to disk, and then return
+/// `Err(ChannelMonitorUpdateErr::TemporaryFailure)` while the update continues in the
+/// background. 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 persistence fails for some reason, implementations should return
+/// `Err(ChannelMonitorUpdateErr::PermanentFailure)`, in which case the channel will likely be
+/// closed without broadcasting the latest state. See
+/// [`ChannelMonitorUpdateErr::PermanentFailure`] for more details.
pub trait Persist<ChannelSigner: Sign> {
- /// Persist a new channel's data. The data can be stored any way you want, but
- /// the identifier provided by Rust-Lightning 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. See the `Persist` trait documentation for more details.
+ /// 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 [`ChannelMonitorUpdateErr::TemporaryFailure`].
///
/// See [`Writeable::write`] on [`ChannelMonitor`] for writing out a `ChannelMonitor`
/// and [`ChannelMonitorUpdateErr`] for requirements when returning errors.
///
+ /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
/// [`Writeable::write`]: crate::util::ser::Writeable::write
- fn persist_new_channel(&self, id: OutPoint, data: &ChannelMonitor<ChannelSigner>) -> Result<(), ChannelMonitorUpdateErr>;
+ fn persist_new_channel(&self, channel_id: OutPoint, data: &ChannelMonitor<ChannelSigner>, update_id: MonitorUpdateId) -> Result<(), ChannelMonitorUpdateErr>;
- /// Update one channel's data. The provided `ChannelMonitor` has already
- /// applied the given update.
+ /// 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.
+ /// 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*
/// 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 [`ChannelMonitorUpdateErr::TemporaryFailure`].
+ ///
/// See [`Writeable::write`] on [`ChannelMonitor`] for writing out a `ChannelMonitor`,
/// [`Writeable::write`] on [`ChannelMonitorUpdate`] for writing out an update, and
/// [`ChannelMonitorUpdateErr`] for requirements when returning errors.
///
/// [`Writeable::write`]: crate::util::ser::Writeable::write
- fn update_persisted_channel(&self, id: OutPoint, update: &ChannelMonitorUpdate, data: &ChannelMonitor<ChannelSigner>) -> Result<(), ChannelMonitorUpdateErr>;
+ fn update_persisted_channel(&self, channel_id: OutPoint, update: &Option<ChannelMonitorUpdate>, data: &ChannelMonitor<ChannelSigner>, update_id: MonitorUpdateId) -> Result<(), ChannelMonitorUpdateErr>;
}
struct MonitorHolder<ChannelSigner: Sign> {
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 TemporaryFailure, 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>>,
+ /// When the user returns a PermanentFailure error from an update_persisted_channel call during
+ /// block processing, we inform the ChannelManager that the channel should be closed
+ /// asynchronously. In order to ensure no further changes happen before the ChannelManager has
+ /// processed the closure event, we set this to true and return PermanentFailure for any other
+ /// chain::Watch events.
+ channel_perm_failed: AtomicBool,
+ /// 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: Sign> 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.
P::Target: Persist<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<MonitorEvent>>,
+ /// The best block height seen, used as a proxy for the passage of time.
+ highest_chain_height: AtomicUsize,
}
impl<ChannelSigner: Sign, C: Deref, T: Deref, F: Deref, L: Deref, P: Deref> ChainMonitor<ChannelSigner, C, T, F, L, P>
/// 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 monitor_states = self.monitors.read().unwrap();
- for monitor_state in monitor_states.values() {
- let mut txn_outputs = process(&monitor_state.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 monitor_states = self.monitors.write().unwrap();
+ 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);
+ }
+ }
+
+ for (funding_outpoint, monitor_state) in monitor_states.iter() {
+ 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
+ // TemporaryFailure 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) {
+ Ok(()) =>
+ log_trace!(self.logger, "Finished syncing Channel Monitor for channel {}", log_funding_info!(monitor)),
+ Err(ChannelMonitorUpdateErr::PermanentFailure) => {
+ monitor_state.channel_perm_failed.store(true, Ordering::Release);
+ self.pending_monitor_events.lock().unwrap().push(MonitorEvent::UpdateFailed(*funding_outpoint));
+ },
+ Err(ChannelMonitorUpdateErr::TemporaryFailure) => {
+ 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);
+ },
+ }
+ }
+
+ // 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);
+ }
}
}
}
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);
+ self.process_chain_data(header, None, &txdata, process); // We skip the best height the second go-around
}
}
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),
}
}
/// Indicates the persistence of a [`ChannelMonitor`] has completed after
/// [`ChannelMonitorUpdateErr::TemporaryFailure`] was returned from an update operation.
///
- /// All ChannelMonitor updates up to and including highest_applied_update_id must have been
- /// fully committed in every copy of the given channels' ChannelMonitors.
- ///
- /// Note that there is no effect to calling with a highest_applied_update_id other than the
- /// current latest ChannelMonitorUpdate and one call to this function after multiple
- /// ChannelMonitorUpdateErr::TemporaryFailures is fine. The highest_applied_update_id field
- /// exists largely only to prevent races between this and concurrent update_monitor calls.
- ///
/// 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 [`ChannelMonitorUpdateErr::TemporaryFailure`],
- /// 2) once all remote copies are updated, you call this function with the update_id that
- /// completed, and once it is the latest the Channel will be re-enabled.
- pub fn channel_monitor_updated(&self, funding_txo: OutPoint, highest_applied_update_id: u64) {
+ /// 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 || monitor_data.channel_perm_failed.load(Ordering::Acquire) {
+ // If there are still monitor updates pending (or an old monitor update
+ // finished after a later one perm-failed), we cannot yet construct an
+ // UpdateCompleted event.
+ return Ok(());
+ }
+ self.pending_monitor_events.lock().unwrap().push(MonitorEvent::UpdateCompleted {
+ funding_txo,
+ monitor_update_id: monitor_data.monitor.get_latest_update_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.
+ }
+ },
+ }
+ Ok(())
+ }
+
+ /// 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) {
self.pending_monitor_events.lock().unwrap().push(MonitorEvent::UpdateCompleted {
- funding_txo, monitor_update_id: highest_applied_update_id
+ funding_txo,
+ monitor_update_id,
});
}
- #[cfg(any(test, feature = "fuzztarget", feature = "_test_utils"))]
+ #[cfg(any(test, fuzzing, feature = "_test_utils"))]
pub fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
use util::events::EventsProvider;
let events = core::cell::RefCell::new(Vec::new());
L::Target: Logger,
P::Target: Persist<ChannelSigner>,
{
- fn block_connected(&self, block: &Block, height: u32) {
- let header = &block.header;
- let txdata: Vec<_> = block.txdata.iter().enumerate().collect();
+ 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, &txdata, |monitor, txdata| {
+ self.process_chain_data(header, Some(height), &txdata, |monitor, txdata| {
monitor.block_connected(
header, txdata, height, &*self.broadcaster, &*self.fee_estimator, &*self.logger)
});
{
fn transactions_confirmed(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
log_debug!(self.logger, "{} provided transactions confirmed at height {} in block {}", txdata.len(), height, header.block_hash());
- self.process_chain_data(header, txdata, |monitor, txdata| {
+ self.process_chain_data(header, None, txdata, |monitor, txdata| {
monitor.transactions_confirmed(
header, txdata, height, &*self.broadcaster, &*self.fee_estimator, &*self.logger)
});
fn best_block_updated(&self, header: &BlockHeader, height: u32) {
log_debug!(self.logger, "New best block {} at height {} provided via best_block_updated", header.block_hash(), height);
- self.process_chain_data(header, &[], |monitor, txdata| {
+ 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());
return Err(ChannelMonitorUpdateErr::PermanentFailure)},
hash_map::Entry::Vacant(e) => e,
};
- let persist_res = self.persister.persist_new_channel(funding_outpoint, &monitor);
+ 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);
if persist_res.is_err() {
- log_error!(self.logger, "Failed to persist new channel data: {:?}", persist_res);
+ log_error!(self.logger, "Failed to persist new ChannelMonitor for channel {}: {:?}", log_funding_info!(monitor), persist_res);
+ } else {
+ log_trace!(self.logger, "Finished persisting new ChannelMonitor for channel {}", log_funding_info!(monitor));
}
if persist_res == Err(ChannelMonitorUpdateErr::PermanentFailure) {
return persist_res;
+ } else if persist_res.is_err() {
+ pending_monitor_updates.push(update_id);
}
- {
- 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(MonitorHolder { monitor });
+ entry.insert(MonitorHolder {
+ monitor,
+ pending_monitor_updates: Mutex::new(pending_monitor_updates),
+ channel_perm_failed: AtomicBool::new(false),
+ last_chain_persist_height: AtomicUsize::new(self.highest_chain_height.load(Ordering::Acquire)),
+ });
persist_res
}
// 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(any(test, fuzzing))]
panic!("ChannelManager generated a channel update for a channel that was not yet registered!");
- #[cfg(not(any(test, feature = "fuzztarget")))]
+ #[cfg(not(any(test, fuzzing)))]
Err(ChannelMonitorUpdateErr::PermanentFailure)
},
Some(monitor_state) => {
let monitor = &monitor_state.monitor;
- log_trace!(self.logger, "Updating Channel Monitor for channel {}", log_funding_info!(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 let Err(e) = &update_res {
- log_error!(self.logger, "Failed to update channel monitor: {:?}", e);
+ 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);
+ if let Err(e) = persist_res {
+ if e == ChannelMonitorUpdateErr::TemporaryFailure {
+ pending_monitor_updates.push(update_id);
+ } else {
+ monitor_state.channel_perm_failed.store(true, Ordering::Release);
+ }
+ log_error!(self.logger, "Failed to persist ChannelMonitor update for channel {}: {:?}", log_funding_info!(monitor), e);
+ } else {
+ log_trace!(self.logger, "Finished persisting ChannelMonitor update for channel {}", log_funding_info!(monitor));
}
if update_res.is_err() {
Err(ChannelMonitorUpdateErr::PermanentFailure)
+ } else if monitor_state.channel_perm_failed.load(Ordering::Acquire) {
+ Err(ChannelMonitorUpdateErr::PermanentFailure)
} else {
persist_res
}
fn release_pending_monitor_events(&self) -> Vec<MonitorEvent> {
let mut pending_monitor_events = self.pending_monitor_events.lock().unwrap().split_off(0);
for monitor_state in self.monitors.read().unwrap().values() {
- pending_monitor_events.append(&mut monitor_state.monitor.get_and_clear_pending_monitor_events());
+ 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_info!(self.logger, "A Channel Monitor sync is still in progress, refusing to provide monitor events!");
+ } else {
+ if monitor_state.channel_perm_failed.load(Ordering::Acquire) {
+ // If a `UpdateOrigin::ChainSync` persistence failed with `PermanantFailure`,
+ // we don't really know if the latest `ChannelMonitor` state is on disk or not.
+ // We're supposed to hold monitor updates until the latest state is on disk to
+ // avoid duplicate events, but the user told us persistence is screw-y and may
+ // not complete. We can't hold events forever because we may learn some payment
+ // preimage, so instead we just log and hope the user complied with the
+ // `PermanentFailure` requirements of having at least the local-disk copy
+ // updated.
+ log_info!(self.logger, "A Channel Monitor sync returned PermanentFailure. Returning monitor events but duplicate events may appear after reload!");
+ }
+ 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.");
+ }
+ pending_monitor_events.append(&mut monitor_state.monitor.get_and_clear_pending_monitor_events());
+ }
}
pending_monitor_events
}
#[cfg(test)]
mod tests {
- use ::{check_added_monitors, get_local_commitment_txn};
+ use bitcoin::BlockHeader;
+ use ::{check_added_monitors, check_closed_broadcast, check_closed_event};
+ use ::{expect_payment_sent, expect_payment_sent_without_paths, expect_payment_path_successful, get_event_msg};
+ use ::{get_htlc_update_msgs, get_local_commitment_txn, get_revoke_commit_msgs, get_route_and_payment_hash, unwrap_send_err};
+ use chain::{ChannelMonitorUpdateErr, Confirm, Watch};
+ use chain::channelmonitor::LATENCY_GRACE_PERIOD_BLOCKS;
+ use ln::channelmanager::PaymentSendFailure;
use ln::features::InitFeatures;
use ln::functional_test_utils::*;
- use util::events::MessageSendEventsProvider;
+ use ln::msgs::ChannelMessageHandler;
+ use util::errors::APIError;
+ use util::events::{ClosureReason, MessageSendEvent, MessageSendEventsProvider};
use util::test_utils::{OnRegisterOutput, TxOutReference};
/// Tests that in-block dependent transactions are processed by `block_connected` when not
nodes[1].node.get_and_clear_pending_msg_events();
nodes[1].node.get_and_clear_pending_events();
}
+
+ #[test]
+ 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);
+ create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
+
+ // Route two payments to be claimed at the same time.
+ let payment_preimage_1 = route_payment(&nodes[0], &[&nodes[1]], 1_000_000).0;
+ let payment_preimage_2 = route_payment(&nodes[0], &[&nodes[1]], 1_000_000).0;
+
+ chanmon_cfgs[1].persister.offchain_monitor_updates.lock().unwrap().clear();
+ chanmon_cfgs[1].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+
+ 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);
+
+ chanmon_cfgs[1].persister.set_update_ret(Ok(()));
+
+ 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();
+ nodes[1].chain_monitor.chain_monitor.channel_monitor_updated(*funding_txo, update_iter.next().unwrap().clone()).unwrap();
+ assert!(nodes[1].chain_monitor.release_pending_monitor_events().is_empty());
+ assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
+ nodes[1].chain_monitor.chain_monitor.channel_monitor_updated(*funding_txo, update_iter.next().unwrap().clone()).unwrap();
+
+ // 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.
+
+ 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_without_paths!(nodes[0], payment_preimage_1);
+ 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());
+
+ 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_without_paths!(nodes[0], payment_preimage_2);
+ 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, InitFeatures::known(), InitFeatures::known());
+
+ // 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 = route_payment(&nodes[0], &[&nodes[1]], 1_000_000).0;
+ nodes[1].node.claim_funds(payment_preimage);
+ nodes[1].node.get_and_clear_pending_msg_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(Err(ChannelMonitorUpdateErr::TemporaryFailure));
+
+ // 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 = BlockHeader {
+ version: 2, time: 0, bits: 0, nonce: 0,
+ prev_blockhash: nodes[0].best_block_info().0,
+ merkle_root: Default::default() };
+ 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(Ok(()));
+ unwrap_send_err!(nodes[0].node.send_payment(&route, second_payment_hash, &Some(second_payment_secret)),
+ true, APIError::ChannelUnavailable { ref err },
+ assert!(err.contains("ChannelMonitor storage failure")));
+ check_added_monitors!(nodes[0], 2); // After the failure we generate a close-channel monitor update
+ check_closed_broadcast!(nodes[0], true);
+ check_closed_event!(nodes[0], 1, ClosureReason::ProcessingError { err: "ChannelMonitor storage failure".to_string() });
+
+ // 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 = BlockHeader {
+ version: 2, time: 0, bits: 0, nonce: 0,
+ prev_blockhash: nodes[0].best_block_info().0,
+ merkle_root: Default::default() };
+ 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);
+ }
+
+ #[test]
+ fn chainsync_pauses_events() {
+ do_chainsync_pauses_events(false);
+ do_chainsync_pauses_events(true);
+ }
+
+ #[test]
+ fn update_during_chainsync_fails_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, InitFeatures::known(), InitFeatures::known());
+
+ chanmon_cfgs[0].persister.chain_sync_monitor_persistences.lock().unwrap().clear();
+ chanmon_cfgs[0].persister.set_update_ret(Err(ChannelMonitorUpdateErr::PermanentFailure));
+
+ connect_blocks(&nodes[0], 1);
+ // Before processing events, the ChannelManager will still think the Channel is open and
+ // there won't be any ChannelMonitorUpdates
+ assert_eq!(nodes[0].node.list_channels().len(), 1);
+ check_added_monitors!(nodes[0], 0);
+ // ... however once we get events once, the channel will close, creating a channel-closed
+ // ChannelMonitorUpdate.
+ check_closed_broadcast!(nodes[0], true);
+ check_closed_event!(nodes[0], 1, ClosureReason::ProcessingError { err: "Failed to persist ChannelMonitor update during chain sync".to_string() });
+ check_added_monitors!(nodes[0], 1);
+ }
}
projects / rust-lightning / blobdiff