From: Duncan Dean <git@dunxen.dev>
Date: Tue, 27 Jun 2023 16:19:35 +0000 (-0400)
Subject: Force close pending channels in `internal_shutdown`
X-Git-Tag: v0.0.116~5^2~2
X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=commitdiff_plain;h=bd297fe39dbe62df8d1dd6b9ea3c1372166a09c4;p=rust-lightning

Force close pending channels in `internal_shutdown`
---

diff --git a/lightning/src/events/mod.rs b/lightning/src/events/mod.rs
index a5a20e7d..d08e563c 100644
--- a/lightning/src/events/mod.rs
+++ b/lightning/src/events/mod.rs
@@ -113,7 +113,7 @@ impl_writeable_tlv_based_enum_upgradable!(PathFailure,
 );
 
 #[derive(Clone, Debug, PartialEq, Eq)]
-/// The reason the channel was closed. See individual variants more details.
+/// The reason the channel was closed. See individual variants for more details.
 pub enum ClosureReason {
 	/// Closure generated from receiving a peer error message.
 	///
@@ -164,7 +164,10 @@ pub enum ClosureReason {
 	///
 	/// [`ChannelMonitor`]: crate::chain::channelmonitor::ChannelMonitor
 	/// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
-	OutdatedChannelManager
+	OutdatedChannelManager,
+	/// The counterparty requested a cooperative close of a channel that had not been funded yet.
+	/// The channel has been immediately closed.
+	CounterpartyCoopClosedUnfundedChannel,
 }
 
 impl core::fmt::Display for ClosureReason {
@@ -184,6 +187,7 @@ impl core::fmt::Display for ClosureReason {
 			},
 			ClosureReason::DisconnectedPeer => f.write_str("the peer disconnected prior to the channel being funded"),
 			ClosureReason::OutdatedChannelManager => f.write_str("the ChannelManager read from disk was stale compared to ChannelMonitor(s)"),
+			ClosureReason::CounterpartyCoopClosedUnfundedChannel => f.write_str("the peer requested the unfunded channel be closed"),
 		}
 	}
 }
@@ -197,6 +201,7 @@ impl_writeable_tlv_based_enum_upgradable!(ClosureReason,
 	(8, ProcessingError) => { (1, err, required) },
 	(10, DisconnectedPeer) => {},
 	(12, OutdatedChannelManager) => {},
+	(13, CounterpartyCoopClosedUnfundedChannel) => {},
 );
 
 /// Intended destination of a failed HTLC as indicated in [`Event::HTLCHandlingFailed`].
diff --git a/lightning/src/ln/channelmanager.rs b/lightning/src/ln/channelmanager.rs
index 75ca8b13..e59c9aee 100644
--- a/lightning/src/ln/channelmanager.rs
+++ b/lightning/src/ln/channelmanager.rs
@@ -5530,38 +5530,50 @@ where
 				})?;
 			let mut peer_state_lock = peer_state_mutex.lock().unwrap();
 			let peer_state = &mut *peer_state_lock;
-			match peer_state.channel_by_id.entry(msg.channel_id.clone()) {
-				hash_map::Entry::Occupied(mut chan_entry) => {
-
-					if !chan_entry.get().received_shutdown() {
-						log_info!(self.logger, "Received a shutdown message from our counterparty for channel {}{}.",
-							log_bytes!(msg.channel_id),
-							if chan_entry.get().sent_shutdown() { " after we initiated shutdown" } else { "" });
-					}
-
-					let funding_txo_opt = chan_entry.get().context.get_funding_txo();
-					let (shutdown, monitor_update_opt, htlcs) = try_chan_entry!(self,
-						chan_entry.get_mut().shutdown(&self.signer_provider, &peer_state.latest_features, &msg), chan_entry);
-					dropped_htlcs = htlcs;
+			// TODO(dunxen): Fix this duplication when we switch to a single map with enums as per
+			// https://github.com/lightningdevkit/rust-lightning/issues/2422
+			if let hash_map::Entry::Occupied(chan_entry) = peer_state.outbound_v1_channel_by_id.entry(msg.channel_id.clone()) {
+				log_error!(self.logger, "Immediately closing unfunded channel {} as peer asked to cooperatively shut it down (which is unnecessary)", log_bytes!(&msg.channel_id[..]));
+				self.issue_channel_close_events(&chan_entry.get().context, ClosureReason::CounterpartyCoopClosedUnfundedChannel);
+				let mut chan = remove_channel!(self, chan_entry);
+				self.finish_force_close_channel(chan.context.force_shutdown(false));
+				return Ok(());
+			} else if let hash_map::Entry::Occupied(chan_entry) = peer_state.inbound_v1_channel_by_id.entry(msg.channel_id.clone()) {
+				log_error!(self.logger, "Immediately closing unfunded channel {} as peer asked to cooperatively shut it down (which is unnecessary)", log_bytes!(&msg.channel_id[..]));
+				self.issue_channel_close_events(&chan_entry.get().context, ClosureReason::CounterpartyCoopClosedUnfundedChannel);
+				let mut chan = remove_channel!(self, chan_entry);
+				self.finish_force_close_channel(chan.context.force_shutdown(false));
+				return Ok(());
+			} else if let hash_map::Entry::Occupied(mut chan_entry) = peer_state.channel_by_id.entry(msg.channel_id.clone()) {
+				if !chan_entry.get().received_shutdown() {
+					log_info!(self.logger, "Received a shutdown message from our counterparty for channel {}{}.",
+						log_bytes!(msg.channel_id),
+						if chan_entry.get().sent_shutdown() { " after we initiated shutdown" } else { "" });
+				}
 
-					if let Some(msg) = shutdown {
-						// We can send the `shutdown` message before updating the `ChannelMonitor`
-						// here as we don't need the monitor update to complete until we send a
-						// `shutdown_signed`, which we'll delay if we're pending a monitor update.
-						peer_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
-							node_id: *counterparty_node_id,
-							msg,
-						});
-					}
+				let funding_txo_opt = chan_entry.get().context.get_funding_txo();
+				let (shutdown, monitor_update_opt, htlcs) = try_chan_entry!(self,
+					chan_entry.get_mut().shutdown(&self.signer_provider, &peer_state.latest_features, &msg), chan_entry);
+				dropped_htlcs = htlcs;
+
+				if let Some(msg) = shutdown {
+					// We can send the `shutdown` message before updating the `ChannelMonitor`
+					// here as we don't need the monitor update to complete until we send a
+					// `shutdown_signed`, which we'll delay if we're pending a monitor update.
+					peer_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
+						node_id: *counterparty_node_id,
+						msg,
+					});
+				}
 
-					// Update the monitor with the shutdown script if necessary.
-					if let Some(monitor_update) = monitor_update_opt {
-						break handle_new_monitor_update!(self, funding_txo_opt.unwrap(), monitor_update,
-							peer_state_lock, peer_state, per_peer_state, chan_entry).map(|_| ());
-					}
-					break Ok(());
-				},
-				hash_map::Entry::Vacant(_) => 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.channel_id))
+				// Update the monitor with the shutdown script if necessary.
+				if let Some(monitor_update) = monitor_update_opt {
+					break handle_new_monitor_update!(self, funding_txo_opt.unwrap(), monitor_update,
+						peer_state_lock, peer_state, per_peer_state, chan_entry).map(|_| ());
+				}
+				break Ok(());
+			} else {
+				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.channel_id))
 			}
 		};
 		for htlc_source in dropped_htlcs.drain(..) {