X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fchain%2Fchainmonitor.rs;h=7d698a220676b8dfd7c9a0df41b0b09f0799e2e9;hb=32d6e91fd6547241a04dc7827e11efe0ed7e5f4f;hp=3a2077209c4ea36ebf3b412a048f845e1b344c1f;hpb=45a6f3392d7868894a42d39cbec4d56d2b176e95;p=rust-lightning diff --git a/lightning/src/chain/chainmonitor.rs b/lightning/src/chain/chainmonitor.rs index 3a207720..7d698a22 100644 --- a/lightning/src/chain/chainmonitor.rs +++ b/lightning/src/chain/chainmonitor.rs @@ -31,12 +31,13 @@ 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::chain::keysinterface::WriteableEcdsaChannelSigner; +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::events; -use crate::util::events::{Event, EventHandler}; +use crate::util::wakers::{Future, Notifier}; use crate::ln::channelmanager::ChannelDetails; use crate::prelude::*; @@ -93,6 +94,17 @@ impl MonitorUpdateId { /// [`ChannelMonitorUpdateStatus::PermanentFailure`], in which case the channel will likely be /// closed without broadcasting the latest state. See /// [`ChannelMonitorUpdateStatus::PermanentFailure`] for more details. +/// +/// Third-party watchtowers may be built as a part of an implementation of this trait, with the +/// advantage that you can control whether to resume channel operation depending on if an update +/// has been persisted to a watchtower. For this, you may find the following methods useful: +/// [`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 { /// 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. @@ -216,8 +228,15 @@ impl Deref for LockedChannelMonitor< /// 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 +/// [`rebroadcast_pending_claims`]: Self::rebroadcast_pending_claims pub struct ChainMonitor where C::Target: chain::Filter, T::Target: BroadcasterInterface, @@ -240,6 +259,8 @@ pub struct ChainMonitor, Option)>>, /// The best block height seen, used as a proxy for the passage of time. highest_chain_height: AtomicUsize, + + event_notifier: Notifier, } impl ChainMonitor @@ -300,6 +321,7 @@ where C::Target: chain::Filter, ChannelMonitorUpdateStatus::PermanentFailure => { monitor_state.channel_perm_failed.store(true, Ordering::Release); self.pending_monitor_events.lock().unwrap().push((*funding_outpoint, vec![MonitorEvent::UpdateFailed(*funding_outpoint)], monitor.get_counterparty_node_id())); + self.event_notifier.notify(); }, ChannelMonitorUpdateStatus::InProgress => { log_debug!(self.logger, "Channel Monitor sync for channel {} in progress, holding events until completion!", log_funding_info!(monitor)); @@ -345,6 +367,7 @@ where C::Target: chain::Filter, persister, pending_monitor_events: Mutex::new(Vec::new()), highest_chain_height: AtomicUsize::new(0), + event_notifier: Notifier::new(), } } @@ -352,8 +375,7 @@ where C::Target: chain::Filter, /// claims which are awaiting confirmation. /// /// Includes the balances from each [`ChannelMonitor`] *except* those included in - /// `ignored_channels`, allowing you to filter out balances from channels which are still open - /// (and whose balance should likely be pulled from the [`ChannelDetails`]). + /// `ignored_channels`. /// /// See [`ChannelMonitor::get_claimable_balances`] for more details on the exact criteria for /// inclusion in the return value. @@ -472,6 +494,7 @@ where C::Target: chain::Filter, } }, } + self.event_notifier.notify(); Ok(()) } @@ -486,11 +509,12 @@ where C::Target: chain::Filter, funding_txo, monitor_update_id, }], counterparty_node_id)); + self.event_notifier.notify(); } - #[cfg(any(test, fuzzing, feature = "_test_utils"))] + #[cfg(any(test, feature = "_test_utils"))] pub fn get_and_clear_pending_events(&self) -> Vec { - use crate::util::events::EventsProvider; + use crate::events::EventsProvider; let events = core::cell::RefCell::new(Vec::new()); let event_handler = |event: events::Event| events.borrow_mut().push(event); self.process_pending_events(&event_handler); @@ -502,16 +526,43 @@ where C::Target: chain::Filter, /// /// See the trait-level documentation of [`EventsProvider`] for requirements. /// - /// [`EventsProvider`]: crate::util::events::EventsProvider + /// [`EventsProvider`]: crate::events::EventsProvider pub async fn process_pending_events_async Future>( &self, handler: H ) { - let mut pending_events = Vec::new(); - for monitor_state in self.monitors.read().unwrap().values() { - pending_events.append(&mut monitor_state.monitor.get_and_clear_pending_events()); + // 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::>(); + 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); } - for event in pending_events { - handler(event).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 + ) } } } @@ -742,30 +793,13 @@ impl, { - #[cfg(not(anchors))] - /// 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(&self, handler: H) where H::Target: EventHandler { - let mut pending_events = Vec::new(); - for monitor_state in self.monitors.read().unwrap().values() { - pending_events.append(&mut monitor_state.monitor.get_and_clear_pending_events()); - } - for event in pending_events { - handler.handle_event(event); - } - } - #[cfg(anchors)] /// 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, this method must be invoked frequently, ideally once for every chain tip - /// update (block connected or disconnected). + /// 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. @@ -773,30 +807,24 @@ impl(&self, handler: H) where H::Target: EventHandler { - let mut pending_events = Vec::new(); for monitor_state in self.monitors.read().unwrap().values() { - pending_events.append(&mut monitor_state.monitor.get_and_clear_pending_events()); - } - for event in pending_events { - handler.handle_event(event); + monitor_state.monitor.process_pending_events(&handler); } } } #[cfg(test)] mod tests { - use bitcoin::{BlockHeader, TxMerkleNode}; - use bitcoin::hashes::Hash; use crate::{check_added_monitors, check_closed_broadcast, check_closed_event}; - use crate::{expect_payment_sent, expect_payment_claimed, expect_payment_sent_without_paths, expect_payment_path_successful, get_event_msg}; + 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::ln::channelmanager::{PaymentSendFailure, PaymentId}; + use crate::events::{Event, ClosureReason, 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; - use crate::util::events::{ClosureReason, MessageSendEvent, MessageSendEventsProvider}; #[test] fn test_async_ooo_offchain_updates() { @@ -819,10 +847,8 @@ mod tests { nodes[1].node.claim_funds(payment_preimage_1); check_added_monitors!(nodes[1], 1); - expect_payment_claimed!(nodes[1], payment_hash_1, 1_000_000); nodes[1].node.claim_funds(payment_preimage_2); check_added_monitors!(nodes[1], 1); - expect_payment_claimed!(nodes[1], payment_hash_2, 1_000_000); let persistences = chanmon_cfgs[1].persister.offchain_monitor_updates.lock().unwrap().clone(); assert_eq!(persistences.len(), 1); @@ -850,14 +876,30 @@ mod tests { .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"), + } + // 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); + 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()); @@ -870,7 +912,7 @@ mod tests { 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); + 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); @@ -918,10 +960,7 @@ mod tests { // 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: TxMerkleNode::all_zeros() }; + 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()); @@ -931,12 +970,14 @@ mod tests { // 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(&route, second_payment_hash, &Some(second_payment_secret), PaymentId(second_payment_hash.0)), - true, APIError::ChannelUnavailable { ref err }, + 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) + ), 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() }); + check_closed_event!(nodes[0], 1, ClosureReason::ProcessingError { err: "ChannelMonitor storage failure".to_string() }, + [nodes[1].node.get_our_node_id()], 100000); // However, as the ChainMonitor is still waiting for the original persistence to complete, // it won't yet release the MonitorEvents. @@ -944,10 +985,7 @@ mod tests { 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: TxMerkleNode::all_zeros() }; + 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(); @@ -958,7 +996,7 @@ mod tests { } } - expect_payment_sent!(nodes[0], payment_preimage); + expect_payment_sent(&nodes[0], payment_preimage, None, true, false); } #[test] @@ -986,7 +1024,8 @@ mod tests { // ... 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_closed_event!(nodes[0], 1, ClosureReason::ProcessingError { err: "Failed to persist ChannelMonitor update during chain sync".to_string() }, + [nodes[1].node.get_our_node_id()], 100000); check_added_monitors!(nodes[0], 1); } }