From e3968e09939b0b48ec7b4b614a75018c0d3114b0 Mon Sep 17 00:00:00 2001 From: Matt Corallo Date: Sat, 12 Jun 2021 21:58:50 +0000 Subject: [PATCH] Send channel_update messages to direct peers on private channels If we are a public node and have a private channel, our counterparty needs to know the fees which we will charge to forward payments to them. Without sending them a channel_update, they have no way to learn that information, resulting in the channel being effectively useless for outbound-from-us payments. This commit fixes our lack of channel_update messages to private channel counterparties, ensuring we always send them a channel_update after the channel funding is confirmed. --- fuzz/src/chanmon_consistency.rs | 24 ++++++- lightning-background-processor/src/lib.rs | 8 ++- lightning/src/ln/chanmon_update_fail_tests.rs | 18 +++-- lightning/src/ln/channelmanager.rs | 66 +++++++++++++++++-- lightning/src/ln/functional_test_utils.rs | 12 +++- lightning/src/ln/functional_tests.rs | 3 +- lightning/src/ln/peer_handler.rs | 6 ++ lightning/src/util/events.rs | 9 +++ 8 files changed, 130 insertions(+), 16 deletions(-) diff --git a/fuzz/src/chanmon_consistency.rs b/fuzz/src/chanmon_consistency.rs index 085e4cb74..158d87149 100644 --- a/fuzz/src/chanmon_consistency.rs +++ b/fuzz/src/chanmon_consistency.rs @@ -571,7 +571,12 @@ pub fn do_test(data: &[u8], out: Out) { events::MessageSendEvent::SendFundingLocked { .. } => continue, events::MessageSendEvent::SendAnnouncementSignatures { .. } => continue, events::MessageSendEvent::PaymentFailureNetworkUpdate { .. } => continue, - _ => panic!("Unhandled message event"), + events::MessageSendEvent::SendChannelUpdate { ref node_id, ref msg } => { + assert_eq!(msg.contents.flags & 2, 0); // The disable bit must never be set! + if Some(*node_id) == expect_drop_id { panic!("peer_disconnected should drop msgs bound for the disconnected peer"); } + *node_id == a_id + }, + _ => panic!("Unhandled message event {:?}", event), }; if push_a { ba_events.push(event); } else { bc_events.push(event); } } @@ -692,7 +697,16 @@ pub fn do_test(data: &[u8], out: Out) { // Can be generated due to a payment forward being rejected due to a // channel having previously failed a monitor update }, - _ => panic!("Unhandled message event"), + events::MessageSendEvent::SendChannelUpdate { ref msg, .. } => { + // When we reconnect we will resend a channel_update to make sure our + // counterparty has the latest parameters for receiving payments + // through us. We do, however, check that the message does not include + // the "disabled" bit, as we should never ever have a channel which is + // disabled when we send such an update (or it may indicate channel + // force-close which we should detect as an error). + assert_eq!(msg.contents.flags & 2, 0); + }, + _ => panic!("Unhandled message event {:?}", event), } if $limit_events != ProcessMessages::AllMessages { break; @@ -722,6 +736,9 @@ pub fn do_test(data: &[u8], out: Out) { events::MessageSendEvent::SendFundingLocked { .. } => {}, events::MessageSendEvent::SendAnnouncementSignatures { .. } => {}, events::MessageSendEvent::PaymentFailureNetworkUpdate { .. } => {}, + events::MessageSendEvent::SendChannelUpdate { ref msg, .. } => { + assert_eq!(msg.contents.flags & 2, 0); // The disable bit must never be set! + }, _ => panic!("Unhandled message event"), } } @@ -737,6 +754,9 @@ pub fn do_test(data: &[u8], out: Out) { events::MessageSendEvent::SendFundingLocked { .. } => {}, events::MessageSendEvent::SendAnnouncementSignatures { .. } => {}, events::MessageSendEvent::PaymentFailureNetworkUpdate { .. } => {}, + events::MessageSendEvent::SendChannelUpdate { ref msg, .. } => { + assert_eq!(msg.contents.flags & 2, 0); // The disable bit must never be set! + }, _ => panic!("Unhandled message event"), } } diff --git a/lightning-background-processor/src/lib.rs b/lightning-background-processor/src/lib.rs index dd13a35b4..8c90532d1 100644 --- a/lightning-background-processor/src/lib.rs +++ b/lightning-background-processor/src/lib.rs @@ -443,9 +443,13 @@ mod tests { // Confirm the funding transaction. confirm_transaction(&mut nodes[0], &funding_tx); + let as_funding = get_event_msg!(nodes[0], MessageSendEvent::SendFundingLocked, nodes[1].node.get_our_node_id()); confirm_transaction(&mut nodes[1], &funding_tx); - nodes[0].node.handle_funding_locked(&nodes[1].node.get_our_node_id(), &get_event_msg!(nodes[1], MessageSendEvent::SendFundingLocked, nodes[0].node.get_our_node_id())); - nodes[1].node.handle_funding_locked(&nodes[0].node.get_our_node_id(), &get_event_msg!(nodes[0], MessageSendEvent::SendFundingLocked, nodes[1].node.get_our_node_id())); + let bs_funding = get_event_msg!(nodes[1], MessageSendEvent::SendFundingLocked, nodes[0].node.get_our_node_id()); + nodes[0].node.handle_funding_locked(&nodes[1].node.get_our_node_id(), &bs_funding); + let _as_channel_update = get_event_msg!(nodes[0], MessageSendEvent::SendChannelUpdate, nodes[1].node.get_our_node_id()); + nodes[1].node.handle_funding_locked(&nodes[0].node.get_our_node_id(), &as_funding); + let _bs_channel_update = get_event_msg!(nodes[1], MessageSendEvent::SendChannelUpdate, nodes[0].node.get_our_node_id()); assert!(bg_processor.stop().is_ok()); diff --git a/lightning/src/ln/chanmon_update_fail_tests.rs b/lightning/src/ln/chanmon_update_fail_tests.rs index dd7b1906c..5f90b030d 100644 --- a/lightning/src/ln/chanmon_update_fail_tests.rs +++ b/lightning/src/ln/chanmon_update_fail_tests.rs @@ -1158,7 +1158,10 @@ fn test_monitor_update_fail_reestablish() { nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish); nodes[1].node.handle_channel_reestablish(&nodes[0].node.get_our_node_id(), &as_reestablish); - assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty()); + assert_eq!( + get_event_msg!(nodes[0], MessageSendEvent::SendChannelUpdate, nodes[1].node.get_our_node_id()) + .contents.flags & 2, 0); // The "disabled" bit should be unset as we just reconnected + nodes[1].logger.assert_log("lightning::ln::channelmanager".to_string(), "Failed to update ChannelMonitor".to_string(), 1); check_added_monitors!(nodes[1], 1); @@ -1172,10 +1175,15 @@ fn test_monitor_update_fail_reestablish() { assert!(bs_reestablish == get_event_msg!(nodes[1], MessageSendEvent::SendChannelReestablish, nodes[0].node.get_our_node_id())); nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish); + assert_eq!( + get_event_msg!(nodes[0], MessageSendEvent::SendChannelUpdate, nodes[1].node.get_our_node_id()) + .contents.flags & 2, 0); // The "disabled" bit should be unset as we just reconnected nodes[1].node.handle_channel_reestablish(&nodes[0].node.get_our_node_id(), &as_reestablish); check_added_monitors!(nodes[1], 0); - assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty()); + assert_eq!( + get_event_msg!(nodes[1], MessageSendEvent::SendChannelUpdate, nodes[0].node.get_our_node_id()) + .contents.flags & 2, 0); // The "disabled" bit should be unset as we just reconnected *nodes[1].chain_monitor.update_ret.lock().unwrap() = Some(Ok(())); let (outpoint, latest_update) = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&chan_1.2).unwrap().clone(); @@ -1352,14 +1360,14 @@ fn claim_while_disconnected_monitor_update_fail() { let bs_reconnect = get_event_msg!(nodes[1], MessageSendEvent::SendChannelReestablish, nodes[0].node.get_our_node_id()); nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reconnect); - assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty()); + let _as_channel_update = get_event_msg!(nodes[0], MessageSendEvent::SendChannelUpdate, nodes[1].node.get_our_node_id()); // Now deliver a's reestablish, freeing the claim from the holding cell, but fail the monitor // update. *nodes[1].chain_monitor.update_ret.lock().unwrap() = Some(Err(ChannelMonitorUpdateErr::TemporaryFailure)); nodes[1].node.handle_channel_reestablish(&nodes[0].node.get_our_node_id(), &as_reconnect); - assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty()); + let _bs_channel_update = get_event_msg!(nodes[1], MessageSendEvent::SendChannelUpdate, nodes[0].node.get_our_node_id()); nodes[1].logger.assert_log("lightning::ln::channelmanager".to_string(), "Failed to update ChannelMonitor".to_string(), 1); check_added_monitors!(nodes[1], 1); assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty()); @@ -1492,7 +1500,9 @@ fn monitor_failed_no_reestablish_response() { let bs_reconnect = get_event_msg!(nodes[1], MessageSendEvent::SendChannelReestablish, nodes[0].node.get_our_node_id()); nodes[1].node.handle_channel_reestablish(&nodes[0].node.get_our_node_id(), &as_reconnect); + let _bs_channel_update = get_event_msg!(nodes[1], MessageSendEvent::SendChannelUpdate, nodes[0].node.get_our_node_id()); nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reconnect); + let _as_channel_update = get_event_msg!(nodes[0], MessageSendEvent::SendChannelUpdate, nodes[1].node.get_our_node_id()); *nodes[1].chain_monitor.update_ret.lock().unwrap() = Some(Ok(())); let (outpoint, latest_update) = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&channel_id).unwrap().clone(); diff --git a/lightning/src/ln/channelmanager.rs b/lightning/src/ln/channelmanager.rs index 5caffe8ee..8dbc17bae 100644 --- a/lightning/src/ln/channelmanager.rs +++ b/lightning/src/ln/channelmanager.rs @@ -1598,6 +1598,7 @@ impl ChannelMana action: msgs::ErrorAction::IgnoreError }); } + log_trace!(self.logger, "Attempting to generate broadcast channel update for channel {}", log_bytes!(chan.channel_id())); self.get_channel_update_for_unicast(chan) } @@ -1607,6 +1608,7 @@ impl ChannelMana /// provided evidence that they know about the existence of the channel. /// May be called with channel_state already locked! fn get_channel_update_for_unicast(&self, chan: &Channel) -> Result { + log_trace!(self.logger, "Attempting to generate channel update for channel {}", log_bytes!(chan.channel_id())); let short_channel_id = match chan.get_short_channel_id() { None => return Err(LightningError{err: "Channel not yet established".to_owned(), action: msgs::ErrorAction::IgnoreError}), Some(id) => id, @@ -2789,7 +2791,8 @@ impl ChannelMana pub fn channel_monitor_updated(&self, funding_txo: &OutPoint, highest_applied_update_id: u64) { let _persistence_guard = PersistenceNotifierGuard::notify_on_drop(&self.total_consistency_lock, &self.persistence_notifier); - let (mut pending_failures, chan_restoration_res) = { + let chan_restoration_res; + let mut pending_failures = { let mut channel_lock = self.channel_state.lock().unwrap(); let channel_state = &mut *channel_lock; let mut channel = match channel_state.by_id.entry(funding_txo.to_channel_id()) { @@ -2801,7 +2804,21 @@ impl ChannelMana } let (raa, commitment_update, order, pending_forwards, pending_failures, funding_broadcastable, funding_locked) = channel.get_mut().monitor_updating_restored(&self.logger); - (pending_failures, handle_chan_restoration_locked!(self, channel_lock, channel_state, channel, raa, commitment_update, order, None, pending_forwards, funding_broadcastable, funding_locked)) + let channel_update = if funding_locked.is_some() && channel.get().is_usable() && !channel.get().should_announce() { + // We only send a channel_update in the case where we are just now sending a + // funding_locked and the channel is in a usable state. Further, we rely on the + // normal announcement_signatures process to send a channel_update for public + // channels, only generating a unicast channel_update if this is a private channel. + Some(events::MessageSendEvent::SendChannelUpdate { + node_id: channel.get().get_counterparty_node_id(), + msg: self.get_channel_update_for_unicast(channel.get()).unwrap(), + }) + } else { None }; + chan_restoration_res = handle_chan_restoration_locked!(self, channel_lock, channel_state, channel, raa, commitment_update, order, None, pending_forwards, funding_broadcastable, funding_locked); + if let Some(upd) = channel_update { + channel_state.pending_msg_events.push(upd); + } + pending_failures }; post_handle_chan_restoration!(self, chan_restoration_res); for failure in pending_failures.drain(..) { @@ -2964,6 +2981,11 @@ impl ChannelMana node_id: counterparty_node_id.clone(), msg: announcement_sigs, }); + } else if chan.get().is_usable() { + channel_state.pending_msg_events.push(events::MessageSendEvent::SendChannelUpdate { + node_id: counterparty_node_id.clone(), + msg: self.get_channel_update_for_unicast(chan.get()).unwrap(), + }); } Ok(()) }, @@ -3394,7 +3416,8 @@ impl ChannelMana } fn internal_channel_reestablish(&self, counterparty_node_id: &PublicKey, msg: &msgs::ChannelReestablish) -> Result<(), MsgHandleErrInternal> { - let (htlcs_failed_forward, need_lnd_workaround, chan_restoration_res) = { + let chan_restoration_res; + let (htlcs_failed_forward, need_lnd_workaround) = { let mut channel_state_lock = self.channel_state.lock().unwrap(); let channel_state = &mut *channel_state_lock; @@ -3409,15 +3432,27 @@ impl ChannelMana // add-HTLCs on disconnect, we may be handed HTLCs to fail backwards here. let (funding_locked, revoke_and_ack, commitment_update, monitor_update_opt, order, htlcs_failed_forward, shutdown) = try_chan_entry!(self, chan.get_mut().channel_reestablish(msg, &self.logger), channel_state, chan); + let mut channel_update = None; if let Some(msg) = shutdown { channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown { node_id: counterparty_node_id.clone(), msg, }); + } else if chan.get().is_usable() { + // If the channel is in a usable state (ie the channel is not being shut + // down), send a unicast channel_update to our counterparty to make sure + // they have the latest channel parameters. + channel_update = Some(events::MessageSendEvent::SendChannelUpdate { + node_id: chan.get().get_counterparty_node_id(), + msg: self.get_channel_update_for_unicast(chan.get()).unwrap(), + }); } let need_lnd_workaround = chan.get_mut().workaround_lnd_bug_4006.take(); - (htlcs_failed_forward, need_lnd_workaround, - handle_chan_restoration_locked!(self, channel_state_lock, channel_state, chan, revoke_and_ack, commitment_update, order, monitor_update_opt, Vec::new(), None, funding_locked)) + chan_restoration_res = handle_chan_restoration_locked!(self, channel_state_lock, channel_state, chan, revoke_and_ack, commitment_update, order, monitor_update_opt, Vec::new(), None, funding_locked); + if let Some(upd) = channel_update { + channel_state.pending_msg_events.push(upd); + } + (htlcs_failed_forward, need_lnd_workaround) }, hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id)) } @@ -3970,6 +4005,12 @@ where node_id: channel.get_counterparty_node_id(), msg: announcement_sigs, }); + } else if channel.is_usable() { + log_trace!(self.logger, "Sending funding_locked WITHOUT announcement_signatures but with private channel_update for our counterparty on channel {}", log_bytes!(channel.channel_id())); + pending_msg_events.push(events::MessageSendEvent::SendChannelUpdate { + node_id: channel.get_counterparty_node_id(), + msg: self.get_channel_update_for_unicast(channel).unwrap(), + }); } else { log_trace!(self.logger, "Sending funding_locked WITHOUT announcement_signatures for {}", log_bytes!(channel.channel_id())); } @@ -4209,6 +4250,7 @@ impl &events::MessageSendEvent::BroadcastChannelAnnouncement { .. } => true, &events::MessageSendEvent::BroadcastNodeAnnouncement { .. } => true, &events::MessageSendEvent::BroadcastChannelUpdate { .. } => true, + &events::MessageSendEvent::SendChannelUpdate { ref node_id, .. } => node_id != counterparty_node_id, &events::MessageSendEvent::HandleError { ref node_id, .. } => node_id != counterparty_node_id, &events::MessageSendEvent::PaymentFailureNetworkUpdate { .. } => true, &events::MessageSendEvent::SendChannelRangeQuery { .. } => false, @@ -5042,7 +5084,19 @@ pub mod bench { Listen::block_connected(&node_b, &block, 1); node_a.handle_funding_locked(&node_b.get_our_node_id(), &get_event_msg!(node_b_holder, MessageSendEvent::SendFundingLocked, node_a.get_our_node_id())); - node_b.handle_funding_locked(&node_a.get_our_node_id(), &get_event_msg!(node_a_holder, MessageSendEvent::SendFundingLocked, node_b.get_our_node_id())); + let msg_events = node_a.get_and_clear_pending_msg_events(); + assert_eq!(msg_events.len(), 2); + match msg_events[0] { + MessageSendEvent::SendFundingLocked { ref msg, .. } => { + node_b.handle_funding_locked(&node_a.get_our_node_id(), msg); + get_event_msg!(node_b_holder, MessageSendEvent::SendChannelUpdate, node_a.get_our_node_id()); + }, + _ => panic!(), + } + match msg_events[1] { + MessageSendEvent::SendChannelUpdate { .. } => {}, + _ => panic!(), + } let dummy_graph = NetworkGraph::new(genesis_hash); diff --git a/lightning/src/ln/functional_test_utils.rs b/lightning/src/ln/functional_test_utils.rs index 00bde294c..e9fae460d 100644 --- a/lightning/src/ln/functional_test_utils.rs +++ b/lightning/src/ln/functional_test_utils.rs @@ -1583,18 +1583,20 @@ macro_rules! handle_chan_reestablish_msgs { let mut revoke_and_ack = None; let mut commitment_update = None; let order = if let Some(ev) = msg_events.get(idx) { - idx += 1; match ev { &MessageSendEvent::SendRevokeAndACK { ref node_id, ref msg } => { assert_eq!(*node_id, $dst_node.node.get_our_node_id()); revoke_and_ack = Some(msg.clone()); + idx += 1; RAACommitmentOrder::RevokeAndACKFirst }, &MessageSendEvent::UpdateHTLCs { ref node_id, ref updates } => { assert_eq!(*node_id, $dst_node.node.get_our_node_id()); commitment_update = Some(updates.clone()); + idx += 1; RAACommitmentOrder::CommitmentFirst }, + &MessageSendEvent::SendChannelUpdate { .. } => RAACommitmentOrder::CommitmentFirst, _ => panic!("Unexpected event"), } } else { @@ -1607,16 +1609,24 @@ macro_rules! handle_chan_reestablish_msgs { assert_eq!(*node_id, $dst_node.node.get_our_node_id()); assert!(revoke_and_ack.is_none()); revoke_and_ack = Some(msg.clone()); + idx += 1; }, &MessageSendEvent::UpdateHTLCs { ref node_id, ref updates } => { assert_eq!(*node_id, $dst_node.node.get_our_node_id()); assert!(commitment_update.is_none()); commitment_update = Some(updates.clone()); + idx += 1; }, + &MessageSendEvent::SendChannelUpdate { .. } => {}, _ => panic!("Unexpected event"), } } + if let Some(&MessageSendEvent::SendChannelUpdate { ref node_id, ref msg }) = msg_events.get(idx) { + assert_eq!(*node_id, $dst_node.node.get_our_node_id()); + assert_eq!(msg.contents.flags & 2, 0); // "disabled" flag must not be set as we just reconnected. + } + (funding_locked, revoke_and_ack, commitment_update, order) } } diff --git a/lightning/src/ln/functional_tests.rs b/lightning/src/ln/functional_tests.rs index df3c64ae8..d6c4716b1 100644 --- a/lightning/src/ln/functional_tests.rs +++ b/lightning/src/ln/functional_tests.rs @@ -1039,7 +1039,8 @@ fn do_test_shutdown_rebroadcast(recv_count: u8) { nodes[0].node.handle_shutdown(&nodes[1].node.get_our_node_id(), &InitFeatures::known(), &node_1_2nd_shutdown); node_0_2nd_shutdown } else { - assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty()); + let node_0_chan_update = get_event_msg!(nodes[0], MessageSendEvent::SendChannelUpdate, nodes[1].node.get_our_node_id()); + assert_eq!(node_0_chan_update.contents.flags & 2, 0); // "disabled" flag must not be set as we just reconnected. nodes[0].node.handle_shutdown(&nodes[1].node.get_our_node_id(), &InitFeatures::known(), &node_1_2nd_shutdown); get_event_msg!(nodes[0], MessageSendEvent::SendShutdown, nodes[1].node.get_our_node_id()) }; diff --git a/lightning/src/ln/peer_handler.rs b/lightning/src/ln/peer_handler.rs index 9e395f110..96ec31c98 100644 --- a/lightning/src/ln/peer_handler.rs +++ b/lightning/src/ln/peer_handler.rs @@ -1264,6 +1264,12 @@ impl PeerManager { + log_trace!(self.logger, "Handling SendChannelUpdate event in peer_handler for node {} for channel {}", + log_pubkey!(node_id), msg.contents.short_channel_id); + let peer = get_peer_for_forwarding!(node_id); + peer.pending_outbound_buffer.push_back(peer.channel_encryptor.encrypt_message(&encode_msg!(msg))); + }, MessageSendEvent::PaymentFailureNetworkUpdate { ref update } => { self.message_handler.route_handler.handle_htlc_fail_channel_update(update); }, diff --git a/lightning/src/util/events.rs b/lightning/src/util/events.rs index dbb4178fb..0fc7c6b3a 100644 --- a/lightning/src/util/events.rs +++ b/lightning/src/util/events.rs @@ -389,6 +389,15 @@ pub enum MessageSendEvent { /// The channel_update which should be sent. msg: msgs::ChannelUpdate, }, + /// Used to indicate that a channel_update should be sent to a single peer. + /// In contrast to [`Self::BroadcastChannelUpdate`], this is used when the channel is a + /// private channel and we shouldn't be informing all of our peers of channel parameters. + SendChannelUpdate { + /// The node_id of the node which should receive this message + node_id: PublicKey, + /// The channel_update which should be sent. + msg: msgs::ChannelUpdate, + }, /// Broadcast an error downstream to be handled HandleError { /// The node_id of the node which should receive this message -- 2.39.5