use chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, Balance, MonitorEvent, TransactionOutputs};
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 prelude::*;
use sync::{RwLock, RwLockReadGuard, Mutex, MutexGuard};
use core::ops::Deref;
+use core::sync::atomic::{AtomicBool, 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.
/// 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`
/// [`ChannelMonitorUpdateErr`] for requirements when returning errors.
///
/// [`Writeable::write`]: crate::util::ser::Writeable::write
- fn update_persisted_channel(&self, channel_id: OutPoint, update: &ChannelMonitorUpdate, data: &ChannelMonitor<ChannelSigner>, update_id: MonitorUpdateId) -> 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> {
/// 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,
}
impl<ChannelSigner: Sign> MonitorHolder<ChannelSigner> {
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>>,
}
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);
+ {
+ let monitor_states = self.monitors.write().unwrap();
+ 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();
+
+ 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);
+ // 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);
+ }
}
}
}
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,
pending_monitor_updates.retain(|update_id| *update_id != completed_update_id);
match completed_update_id {
- MonitorUpdateId { .. } => {
+ 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
// `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 an
+ 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(());
}
funding_txo,
monitor_update_id: monitor_data.monitor.get_latest_update_id(),
});
- }
+ },
+ MonitorUpdateId { contents: UpdateOrigin::ChainSync(_) } => {
+ // We've already done everything we need to, the next time
+ // release_pending_monitor_events is called, any events for this ChannelMonitor
+ // will be returned if there's no more SyncPersistId events left.
+ },
}
Ok(())
}
monitor.load_outputs_to_watch(chain_source);
}
}
- entry.insert(MonitorHolder { monitor, pending_monitor_updates: Mutex::new(pending_monitor_updates) });
+ entry.insert(MonitorHolder {
+ monitor,
+ pending_monitor_updates: Mutex::new(pending_monitor_updates),
+ channel_perm_failed: AtomicBool::new(false),
+ });
persist_res
}
// still be changed. So, persist the updated monitor despite the error.
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, &update, monitor, update_id);
+ 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 channel monitor update: {:?}", e);
}
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 {
+ 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!");
+ }
+ pending_monitor_events.append(&mut monitor_state.monitor.get_and_clear_pending_monitor_events());
+ }
}
pending_monitor_events
}
self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_update.source, &htlc_update.payment_hash, HTLCFailReason::Reason { failure_code: 0x4000 | 8, data: Vec::new() });
}
},
- MonitorEvent::CommitmentTxConfirmed(funding_outpoint) => {
+ MonitorEvent::CommitmentTxConfirmed(funding_outpoint) |
+ MonitorEvent::UpdateFailed(funding_outpoint) => {
let mut channel_lock = self.channel_state.lock().unwrap();
let channel_state = &mut *channel_lock;
let by_id = &mut channel_state.by_id;
msg: update
});
}
- self.issue_channel_close_events(&chan, ClosureReason::CommitmentTxConfirmed);
+ let reason = if let MonitorEvent::UpdateFailed(_) = monitor_event {
+ ClosureReason::ProcessingError { err: "Failed to persist ChannelMonitor update during chain sync".to_string() }
+ } else {
+ ClosureReason::CommitmentTxConfirmed
+ };
+ self.issue_channel_close_events(&chan, reason);
pending_msg_events.push(events::MessageSendEvent::HandleError {
node_id: chan.get_counterparty_node_id(),
action: msgs::ErrorAction::SendErrorMessage {
///
/// At a high-level, the process for deserializing a ChannelManager and resuming normal operation
/// is:
-/// 1) Deserialize all stored ChannelMonitors.
-/// 2) Deserialize the ChannelManager by filling in this struct and calling:
-/// <(BlockHash, ChannelManager)>::read(reader, args)
-/// This may result in closing some Channels if the ChannelMonitor is newer than the stored
-/// ChannelManager state to ensure no loss of funds. Thus, transactions may be broadcasted.
-/// 3) If you are not fetching full blocks, register all relevant ChannelMonitor outpoints the same
-/// way you would handle a `chain::Filter` call using ChannelMonitor::get_outputs_to_watch() and
-/// ChannelMonitor::get_funding_txo().
-/// 4) Reconnect blocks on your ChannelMonitors.
-/// 5) Disconnect/connect blocks on the ChannelManager.
-/// 6) Move the ChannelMonitors into your local chain::Watch.
+/// 1) Deserialize all stored [`ChannelMonitor`]s.
+/// 2) Deserialize the [`ChannelManager`] by filling in this struct and calling:
+/// `<(BlockHash, ChannelManager)>::read(reader, args)`
+/// This may result in closing some channels if the [`ChannelMonitor`] is newer than the stored
+/// [`ChannelManager`] state to ensure no loss of funds. Thus, transactions may be broadcasted.
+/// 3) If you are not fetching full blocks, register all relevant [`ChannelMonitor`] outpoints the
+/// same way you would handle a [`chain::Filter`] call using
+/// [`ChannelMonitor::get_outputs_to_watch`] and [`ChannelMonitor::get_funding_txo`].
+/// 4) Reconnect blocks on your [`ChannelMonitor`]s.
+/// 5) Disconnect/connect blocks on the [`ChannelManager`].
+/// 6) Re-persist the [`ChannelMonitor`]s to ensure the latest state is on disk.
+/// Note that if you're using a [`ChainMonitor`] for your [`chain::Watch`] implementation, you
+/// will likely accomplish this as a side-effect of calling [`chain::Watch::watch_channel`] in
+/// the next step.
+/// 7) Move the [`ChannelMonitor`]s into your local [`chain::Watch`]. If you're using a
+/// [`ChainMonitor`], this is done by calling [`chain::Watch::watch_channel`].
///
-/// Note that the ordering of #4-6 is not of importance, however all three must occur before you
-/// call any other methods on the newly-deserialized ChannelManager.
+/// Note that the ordering of #4-7 is not of importance, however all four must occur before you
+/// call any other methods on the newly-deserialized [`ChannelManager`].
///
/// Note that because some channels may be closed during deserialization, it is critical that you
/// always deserialize only the latest version of a ChannelManager and ChannelMonitors available to
/// broadcast), and then later deserialize a newer version of the same ChannelManager (which will
/// not force-close the same channels but consider them live), you may end up revoking a state for
/// which you've already broadcasted the transaction.
+///
+/// [`ChainMonitor`]: crate::chain::chainmonitor::ChainMonitor
pub struct ChannelManagerReadArgs<'a, Signer: 'a + Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
where M::Target: chain::Watch<Signer>,
T::Target: BroadcasterInterface,
projects / rust-lightning / commitdiff