//! update [`ChannelMonitor`]s accordingly. If any on-chain events need further processing, it will
//! make those available as [`MonitorEvent`]s to be consumed.
//!
-//! `ChainMonitor` is parameterized by an optional chain source, which must implement the
+//! [`ChainMonitor`] is parameterized by an optional chain source, which must implement the
//! [`chain::Filter`] trait. This provides a mechanism to signal new relevant outputs back to light
//! clients, such that transactions spending those outputs are included in block data.
//!
-//! `ChainMonitor` may be used directly to monitor channels locally or as a part of a distributed
-//! setup to monitor channels remotely. In the latter case, a custom `chain::Watch` implementation
+//! [`ChainMonitor`] may be used directly to monitor channels locally or as a part of a distributed
+//! setup to monitor channels remotely. In the latter case, a custom [`chain::Watch`] implementation
//! would be responsible for routing each update to a remote server and for retrieving monitor
-//! events. The remote server would make use of `ChainMonitor` for block processing and for
-//! servicing `ChannelMonitor` updates from the client.
-//!
-//! [`ChainMonitor`]: struct.ChainMonitor.html
-//! [`chain::Filter`]: ../trait.Filter.html
-//! [`chain::Watch`]: ../trait.Watch.html
-//! [`ChannelMonitor`]: ../channelmonitor/struct.ChannelMonitor.html
-//! [`MonitorEvent`]: ../channelmonitor/enum.MonitorEvent.html
+//! events. The remote server would make use of [`ChainMonitor`] for block processing and for
+//! servicing [`ChannelMonitor`] updates from the client.
-use bitcoin::blockdata::block::BlockHeader;
+use bitcoin::blockdata::block::{Block, BlockHeader};
+use bitcoin::hash_types::Txid;
use chain;
-use chain::Filter;
+use chain::{Filter, WatchedOutput};
use chain::chaininterface::{BroadcasterInterface, FeeEstimator};
use chain::channelmonitor;
-use chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateErr, MonitorEvent, Persist};
+use chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateErr, MonitorEvent, Persist, TransactionOutputs};
use chain::transaction::{OutPoint, TransactionData};
-use chain::keysinterface::ChannelKeys;
+use chain::keysinterface::Sign;
use util::logger::Logger;
use util::events;
-use util::events::Event;
+use util::events::EventHandler;
-use std::collections::{HashMap, hash_map};
-use std::sync::Mutex;
-use std::ops::Deref;
+use prelude::*;
+use sync::RwLock;
+use core::ops::Deref;
/// An implementation of [`chain::Watch`] for monitoring channels.
///
/// or used independently to monitor channels remotely. See the [module-level documentation] for
/// details.
///
-/// [`chain::Watch`]: ../trait.Watch.html
-/// [`ChannelManager`]: ../../ln/channelmanager/struct.ChannelManager.html
-/// [module-level documentation]: index.html
-pub struct ChainMonitor<ChanSigner: ChannelKeys, C: Deref, T: Deref, F: Deref, L: Deref, P: Deref>
+/// [`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>
where C::Target: chain::Filter,
T::Target: BroadcasterInterface,
F::Target: FeeEstimator,
L::Target: Logger,
- P::Target: channelmonitor::Persist<ChanSigner>,
+ P::Target: channelmonitor::Persist<ChannelSigner>,
{
/// The monitors
- pub monitors: Mutex<HashMap<OutPoint, ChannelMonitor<ChanSigner>>>,
+ pub monitors: RwLock<HashMap<OutPoint, ChannelMonitor<ChannelSigner>>>,
chain_source: Option<C>,
broadcaster: T,
logger: L,
persister: P,
}
-impl<ChanSigner: ChannelKeys, C: Deref, T: Deref, F: Deref, L: Deref, P: Deref> ChainMonitor<ChanSigner, C, T, F, L, P>
+impl<ChannelSigner: Sign, 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<ChanSigner>,
+ P::Target: channelmonitor::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 connected block. See
+ /// of a channel and reacting accordingly based on transactions in the given chain data. See
/// [`ChannelMonitor::block_connected`] for details. Any HTLCs that were resolved on chain will
/// be returned by [`chain::Watch::release_pending_monitor_events`].
///
/// 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`.
- ///
- /// [`ChannelMonitor::block_connected`]: ../channelmonitor/struct.ChannelMonitor.html#method.block_connected
- /// [`chain::Watch::release_pending_monitor_events`]: ../trait.Watch.html#tymethod.release_pending_monitor_events
- /// [`chain::Filter`]: ../trait.Filter.html
- pub fn block_connected(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
- let mut monitors = self.monitors.lock().unwrap();
- for monitor in monitors.values_mut() {
- let mut txn_outputs = monitor.block_connected(header, txdata, height, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
+ fn process_chain_data<FN>(&self, header: &BlockHeader, 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 {
- for (txid, outputs) in txn_outputs.drain(..) {
- for (idx, output) in outputs.iter() {
- chain_source.register_output(&OutPoint { txid, index: *idx as u16 }, &output.script_pubkey);
+ 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);
+ }
}
}
}
}
- }
- /// Dispatches to per-channel monitors, which are responsible for updating their on-chain view
- /// of a channel based on the disconnected block. See [`ChannelMonitor::block_disconnected`] for
- /// details.
- ///
- /// [`ChannelMonitor::block_disconnected`]: ../channelmonitor/struct.ChannelMonitor.html#method.block_disconnected
- pub fn block_disconnected(&self, header: &BlockHeader, disconnected_height: u32) {
- let mut monitors = self.monitors.lock().unwrap();
- for monitor in monitors.values_mut() {
- monitor.block_disconnected(header, disconnected_height, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
+ // 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);
}
}
/// pre-filter blocks or only fetch blocks matching a compact filter. Otherwise, clients may
/// always need to fetch full blocks absent another means for determining which blocks contain
/// transactions relevant to the watched channels.
- ///
- /// [`chain::Filter`]: ../trait.Filter.html
pub fn new(chain_source: Option<C>, broadcaster: T, logger: L, feeest: F, persister: P) -> Self {
Self {
- monitors: Mutex::new(HashMap::new()),
+ monitors: RwLock::new(HashMap::new()),
chain_source,
broadcaster,
logger,
persister,
}
}
+
+ #[cfg(any(test, feature = "fuzztarget", 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());
+ let event_handler = |event| events.borrow_mut().push(event);
+ self.process_pending_events(&event_handler);
+ events.into_inner()
+ }
+}
+
+impl<ChannelSigner: Sign, 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>,
+{
+ 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| {
+ 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(
+ header, height, &*self.broadcaster, &*self.fee_estimator, &*self.logger);
+ }
+ }
+}
+
+impl<ChannelSigner: Sign, 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>,
+{
+ fn transactions_confirmed(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
+ self.process_chain_data(header, 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);
+ }
+ }
+
+ fn best_block_updated(&self, header: &BlockHeader, height: u32) {
+ self.process_chain_data(header, &[], |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());
+ monitor.best_block_updated(
+ header, height, &*self.broadcaster, &*self.fee_estimator, &*self.logger)
+ });
+ }
+
+ fn get_relevant_txids(&self) -> Vec<Txid> {
+ let mut txids = Vec::new();
+ let monitors = self.monitors.read().unwrap();
+ for monitor in monitors.values() {
+ txids.append(&mut monitor.get_relevant_txids());
+ }
+
+ txids.sort_unstable();
+ txids.dedup();
+ txids
+ }
}
-impl<ChanSigner: ChannelKeys, C: Deref + Sync + Send, T: Deref + Sync + Send, F: Deref + Sync + Send, L: Deref + Sync + Send, P: Deref + Sync + Send> chain::Watch for ChainMonitor<ChanSigner, C, T, F, L, P>
+impl<ChannelSigner: Sign, 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<ChanSigner>,
+ P::Target: channelmonitor::Persist<ChannelSigner>,
{
- type Keys = ChanSigner;
-
/// 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.
- ///
- /// [`chain::Filter`]: ../trait.Filter.html
- fn watch_channel(&self, funding_outpoint: OutPoint, monitor: ChannelMonitor<ChanSigner>) -> Result<(), ChannelMonitorUpdateErr> {
- let mut monitors = self.monitors.lock().unwrap();
+ fn watch_channel(&self, funding_outpoint: OutPoint, monitor: ChannelMonitor<ChannelSigner>) -> Result<(), ChannelMonitorUpdateErr> {
+ 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");
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 {
- chain_source.register_tx(&funding_txo.0.txid, &funding_txo.1);
- for (txid, outputs) in monitor.get_outputs_to_watch().iter() {
- for (idx, script_pubkey) in outputs.iter() {
- chain_source.register_output(&OutPoint { txid: *txid, index: *idx as u16 }, script_pubkey);
- }
- }
+ monitor.load_outputs_to_watch(chain_source);
}
}
entry.insert(monitor);
/// `ChainMonitor` monitors lock.
fn update_channel(&self, funding_txo: OutPoint, update: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr> {
// Update the monitor that watches the channel referred to by the given outpoint.
- let mut monitors = self.monitors.lock().unwrap();
- match monitors.get_mut(&funding_txo) {
+ let monitors = self.monitors.read().unwrap();
+ 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"))]
+ panic!("ChannelManager generated a channel update for a channel that was not yet registered!");
+ #[cfg(not(any(test, feature = "fuzztarget")))]
Err(ChannelMonitorUpdateErr::PermanentFailure)
},
- Some(orig_monitor) => {
- log_trace!(self.logger, "Updating Channel Monitor for channel {}", log_funding_info!(orig_monitor));
- let update_res = orig_monitor.update_monitor(&update, &self.broadcaster, &self.logger);
+ 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);
}
// 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, orig_monitor);
+ 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);
}
fn release_pending_monitor_events(&self) -> Vec<MonitorEvent> {
let mut pending_monitor_events = Vec::new();
- for chan in self.monitors.lock().unwrap().values_mut() {
- pending_monitor_events.append(&mut chan.get_and_clear_pending_monitor_events());
+ for monitor in self.monitors.read().unwrap().values() {
+ pending_monitor_events.append(&mut monitor.get_and_clear_pending_monitor_events());
}
pending_monitor_events
}
}
-impl<ChanSigner: ChannelKeys, C: Deref, T: Deref, F: Deref, L: Deref, P: Deref> events::EventsProvider for ChainMonitor<ChanSigner, C, T, F, L, P>
+impl<ChannelSigner: Sign, 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<ChanSigner>,
+ P::Target: channelmonitor::Persist<ChannelSigner>,
{
- fn get_and_clear_pending_events(&self) -> Vec<Event> {
+ /// Processes [`SpendableOutputs`] events produced from each [`ChannelMonitor`] upon maturity.
+ ///
+ /// 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
+ fn process_pending_events<H: Deref>(&self, handler: H) where H::Target: EventHandler {
let mut pending_events = Vec::new();
- for chan in self.monitors.lock().unwrap().values_mut() {
- pending_events.append(&mut chan.get_and_clear_pending_events());
+ for monitor in self.monitors.read().unwrap().values() {
+ pending_events.append(&mut monitor.get_and_clear_pending_events());
}
- pending_events
+ for event in pending_events.drain(..) {
+ handler.handle_event(event);
+ }
+ }
+}
+
+#[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.
+ #[test]
+ fn connect_block_checks_dependent_transactions() {
+ 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());
+
+ // 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);
+
+ assert_eq!(txn.len(), 2);
+ (txn.remove(0), txn.remove(0))
+ };
+
+ // 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 });
+
+ // 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);
+
+ // Clean up so uninteresting assertions don't fail.
+ check_added_monitors!(nodes[1], 1);
+ nodes[1].node.get_and_clear_pending_msg_events();
+ nodes[1].node.get_and_clear_pending_events();
}
}
projects / rust-lightning / blobdiff