From e9452c701bd38a343cc44eed3c1f5892e047508e Mon Sep 17 00:00:00 2001 From: Matt Corallo Date: Thu, 30 Nov 2023 00:04:09 +0000 Subject: [PATCH] Consistently clean up when failing in `internal_funding_created` When we fail to accept a counterparty's funding for various reasons, we should ensure we call the correct cleanup methods in `internal_funding_created` to remove the temporary data for the channel in our various internal structs (primarily the SCID alias map). This adds the missing cleanup, using `convert_chan_phase_err` consistently in all the error paths. This also ensures we get a `ChannelClosed` event when relevant. --- lightning/src/ln/channel.rs | 14 ++++++ lightning/src/ln/channelmanager.rs | 56 +++++++++++++---------- lightning/src/ln/functional_test_utils.rs | 12 +++++ lightning/src/ln/functional_tests.rs | 54 ++++++++++++++++++++++ 4 files changed, 112 insertions(+), 24 deletions(-) diff --git a/lightning/src/ln/channel.rs b/lightning/src/ln/channel.rs index c5f2e0c7..28842b1b 100644 --- a/lightning/src/ln/channel.rs +++ b/lightning/src/ln/channel.rs @@ -2920,6 +2920,20 @@ impl Channel where self.context.channel_state.clear_waiting_for_batch(); } + /// Unsets the existing funding information. + /// + /// This must only be used if the channel has not yet completed funding and has not been used. + /// + /// Further, the channel must be immediately shut down after this with a call to + /// [`ChannelContext::force_shutdown`]. + pub fn unset_funding_info(&mut self, temporary_channel_id: ChannelId) { + debug_assert!(matches!( + self.context.channel_state, ChannelState::AwaitingChannelReady(_) + )); + self.context.channel_transaction_parameters.funding_outpoint = None; + self.context.channel_id = temporary_channel_id; + } + /// Handles a channel_ready message from our peer. If we've already sent our channel_ready /// and the channel is now usable (and public), this may generate an announcement_signatures to /// reply with. diff --git a/lightning/src/ln/channelmanager.rs b/lightning/src/ln/channelmanager.rs index 9d5cf7e9..08296c43 100644 --- a/lightning/src/ln/channelmanager.rs +++ b/lightning/src/ln/channelmanager.rs @@ -1251,7 +1251,10 @@ where /// required to access the channel with the `counterparty_node_id`. /// /// See `ChannelManager` struct-level documentation for lock order requirements. + #[cfg(not(test))] outpoint_to_peer: Mutex>, + #[cfg(test)] + pub(crate) outpoint_to_peer: Mutex>, /// SCIDs (and outbound SCID aliases) -> `counterparty_node_id`s and `channel_id`s. /// @@ -6205,44 +6208,55 @@ where let mut peer_state_lock = peer_state_mutex.lock().unwrap(); let peer_state = &mut *peer_state_lock; - let (chan, funding_msg_opt, monitor) = + let (mut chan, funding_msg_opt, monitor) = match peer_state.channel_by_id.remove(&msg.temporary_channel_id) { Some(ChannelPhase::UnfundedInboundV1(inbound_chan)) => { let logger = WithChannelContext::from(&self.logger, &inbound_chan.context); match inbound_chan.funding_created(msg, best_block, &self.signer_provider, &&logger) { Ok(res) => res, - Err((mut inbound_chan, err)) => { + Err((inbound_chan, err)) => { // We've already removed this inbound channel from the map in `PeerState` // above so at this point we just need to clean up any lingering entries // concerning this channel as it is safe to do so. - update_maps_on_chan_removal!(self, &inbound_chan.context); - let user_id = inbound_chan.context.get_user_id(); - let shutdown_res = inbound_chan.context.force_shutdown(false); - return Err(MsgHandleErrInternal::from_finish_shutdown(format!("{}", err), - msg.temporary_channel_id, user_id, shutdown_res, None, inbound_chan.context.get_value_satoshis())); + debug_assert!(matches!(err, ChannelError::Close(_))); + // Really we should be returning the channel_id the peer expects based + // on their funding info here, but they're horribly confused anyway, so + // there's not a lot we can do to save them. + return Err(convert_chan_phase_err!(self, err, &mut ChannelPhase::UnfundedInboundV1(inbound_chan), &msg.temporary_channel_id).1); }, } }, - Some(ChannelPhase::Funded(_)) | Some(ChannelPhase::UnfundedOutboundV1(_)) => { - return Err(MsgHandleErrInternal::send_err_msg_no_close(format!("Got an unexpected funding_created message from peer with counterparty_node_id {}", counterparty_node_id), msg.temporary_channel_id)); + Some(mut phase) => { + let err_msg = format!("Got an unexpected funding_created message from peer with counterparty_node_id {}", counterparty_node_id); + let err = ChannelError::Close(err_msg); + return Err(convert_chan_phase_err!(self, err, &mut phase, &msg.temporary_channel_id).1); }, None => return Err(MsgHandleErrInternal::send_err_msg_no_close(format!("Got a message for a channel from the wrong node! No such channel for the passed counterparty_node_id {}", counterparty_node_id), msg.temporary_channel_id)) }; - match peer_state.channel_by_id.entry(chan.context.channel_id()) { + let funded_channel_id = chan.context.channel_id(); + + macro_rules! fail_chan { ($err: expr) => { { + // Note that at this point we've filled in the funding outpoint on our + // channel, but its actually in conflict with another channel. Thus, if + // we call `convert_chan_phase_err` immediately (thus calling + // `update_maps_on_chan_removal`), we'll remove the existing channel + // from `outpoint_to_peer`. Thus, we must first unset the funding outpoint + // on the channel. + let err = ChannelError::Close($err.to_owned()); + chan.unset_funding_info(msg.temporary_channel_id); + return Err(convert_chan_phase_err!(self, err, chan, &funded_channel_id, UNFUNDED_CHANNEL).1); + } } } + + match peer_state.channel_by_id.entry(funded_channel_id) { hash_map::Entry::Occupied(_) => { - Err(MsgHandleErrInternal::send_err_msg_no_close( - "Already had channel with the new channel_id".to_owned(), - chan.context.channel_id() - )) + fail_chan!("Already had channel with the new channel_id"); }, hash_map::Entry::Vacant(e) => { let mut outpoint_to_peer_lock = self.outpoint_to_peer.lock().unwrap(); match outpoint_to_peer_lock.entry(monitor.get_funding_txo().0) { hash_map::Entry::Occupied(_) => { - return Err(MsgHandleErrInternal::send_err_msg_no_close( - "The funding_created message had the same funding_txid as an existing channel - funding is not possible".to_owned(), - chan.context.channel_id())) + fail_chan!("The funding_created message had the same funding_txid as an existing channel - funding is not possible"); }, hash_map::Entry::Vacant(i_e) => { let monitor_res = self.chain_monitor.watch_channel(monitor.get_funding_txo().0, monitor); @@ -6271,13 +6285,7 @@ where } else { let logger = WithChannelContext::from(&self.logger, &chan.context); log_error!(logger, "Persisting initial ChannelMonitor failed, implying the funding outpoint was duplicated"); - let channel_id = match funding_msg_opt { - Some(msg) => msg.channel_id, - None => chan.context.channel_id(), - }; - return Err(MsgHandleErrInternal::send_err_msg_no_close( - "The funding_created message had the same funding_txid as an existing channel - funding is not possible".to_owned(), - channel_id)); + fail_chan!("Duplicate funding outpoint"); } } } diff --git a/lightning/src/ln/functional_test_utils.rs b/lightning/src/ln/functional_test_utils.rs index d3d2e332..eba30404 100644 --- a/lightning/src/ln/functional_test_utils.rs +++ b/lightning/src/ln/functional_test_utils.rs @@ -1536,6 +1536,18 @@ pub struct ExpectedCloseEvent { pub reason: Option, } +impl ExpectedCloseEvent { + pub fn from_id_reason(channel_id: ChannelId, discard_funding: bool, reason: ClosureReason) -> Self { + Self { + channel_capacity_sats: None, + channel_id: Some(channel_id), + counterparty_node_id: None, + discard_funding, + reason: Some(reason), + } + } +} + /// Check that multiple channel closing events have been issued. pub fn check_closed_events(node: &Node, expected_close_events: &[ExpectedCloseEvent]) { let closed_events_count = expected_close_events.len(); diff --git a/lightning/src/ln/functional_tests.rs b/lightning/src/ln/functional_tests.rs index fee3a3b3..fca6abb3 100644 --- a/lightning/src/ln/functional_tests.rs +++ b/lightning/src/ln/functional_tests.rs @@ -8970,6 +8970,54 @@ fn test_duplicate_temporary_channel_id_from_different_peers() { } } +#[test] +fn test_duplicate_funding_err_in_funding() { + // Test that if we have a live channel with one peer, then another peer comes along and tries + // to create a second channel with the same txid we'll fail and not overwrite the + // outpoint_to_peer map in `ChannelManager`. + // + // This was previously broken. + let chanmon_cfgs = create_chanmon_cfgs(3); + let node_cfgs = create_node_cfgs(3, &chanmon_cfgs); + let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]); + let nodes = create_network(3, &node_cfgs, &node_chanmgrs); + + let (_, _, _, real_channel_id, funding_tx) = create_chan_between_nodes(&nodes[0], &nodes[1]); + let real_chan_funding_txo = chain::transaction::OutPoint { txid: funding_tx.txid(), index: 0 }; + assert_eq!(real_chan_funding_txo.to_channel_id(), real_channel_id); + + nodes[2].node.create_channel(nodes[1].node.get_our_node_id(), 100_000, 0, 42, None, None).unwrap(); + let mut open_chan_msg = get_event_msg!(nodes[2], MessageSendEvent::SendOpenChannel, nodes[1].node.get_our_node_id()); + let node_c_temp_chan_id = open_chan_msg.temporary_channel_id; + open_chan_msg.temporary_channel_id = real_channel_id; + nodes[1].node.handle_open_channel(&nodes[2].node.get_our_node_id(), &open_chan_msg); + let mut accept_chan_msg = get_event_msg!(nodes[1], MessageSendEvent::SendAcceptChannel, nodes[2].node.get_our_node_id()); + accept_chan_msg.temporary_channel_id = node_c_temp_chan_id; + nodes[2].node.handle_accept_channel(&nodes[1].node.get_our_node_id(), &accept_chan_msg); + + // Now that we have a second channel with the same funding txo, send a bogus funding message + // and let nodes[1] remove the inbound channel. + let (_, funding_tx, _) = create_funding_transaction(&nodes[2], &nodes[1].node.get_our_node_id(), 100_000, 42); + + nodes[2].node.funding_transaction_generated(&node_c_temp_chan_id, &nodes[1].node.get_our_node_id(), funding_tx).unwrap(); + + let mut funding_created_msg = get_event_msg!(nodes[2], MessageSendEvent::SendFundingCreated, nodes[1].node.get_our_node_id()); + funding_created_msg.temporary_channel_id = real_channel_id; + // Make the signature invalid by changing the funding output + funding_created_msg.funding_output_index += 10; + nodes[1].node.handle_funding_created(&nodes[2].node.get_our_node_id(), &funding_created_msg); + get_err_msg(&nodes[1], &nodes[2].node.get_our_node_id()); + let err = "Invalid funding_created signature from peer".to_owned(); + let reason = ClosureReason::ProcessingError { err }; + let expected_closing = ExpectedCloseEvent::from_id_reason(real_channel_id, false, reason); + check_closed_events(&nodes[1], &[expected_closing]); + + assert_eq!( + *nodes[1].node.outpoint_to_peer.lock().unwrap().get(&real_chan_funding_txo).unwrap(), + nodes[0].node.get_our_node_id() + ); +} + #[test] fn test_duplicate_chan_id() { // Test that if a given peer tries to open a channel with the same channel_id as one that is @@ -9080,6 +9128,12 @@ fn test_duplicate_chan_id() { // without trying to persist the `ChannelMonitor`. check_added_monitors!(nodes[1], 0); + check_closed_events(&nodes[1], &[ + ExpectedCloseEvent::from_id_reason(channel_id, false, ClosureReason::ProcessingError { + err: "Already had channel with the new channel_id".to_owned() + }) + ]); + // ...still, nodes[1] will reject the duplicate channel. { let events = nodes[1].node.get_and_clear_pending_msg_events(); -- 2.30.2