Merge pull request lightningdevkit#1429 from TheBlueMatt/2022-04-drop-no-conn-possible

Author: TheBlueMatt

lightning/src/ln/channelmanager.rs

@@ -5698,39 +5698,21 @@ impl<Signer: Sign, M: Deref , T: Deref , K: Deref , F: Deref , L: Deref >
 			let channel_state = &mut *channel_state_lock;
 			let pending_msg_events = &mut channel_state.pending_msg_events;
 			let short_to_id = &mut channel_state.short_to_id;
-			if no_connection_possible {
-				log_debug!(self.logger, "Failing all channels with {} due to no_connection_possible", log_pubkey!(counterparty_node_id));
-				channel_state.by_id.retain(|_, chan| {
-					if chan.get_counterparty_node_id() == *counterparty_node_id {
+			log_debug!(self.logger, "Marking channels with {} disconnected and generating channel_updates. We believe we {} make future connections to this peer.",
+				log_pubkey!(counterparty_node_id), if no_connection_possible { "cannot" } else { "can" });
+			channel_state.by_id.retain(|_, chan| {
+				if chan.get_counterparty_node_id() == *counterparty_node_id {
+					chan.remove_uncommitted_htlcs_and_mark_paused(&self.logger);
+					if chan.is_shutdown() {
 						update_maps_on_chan_removal!(self, short_to_id, chan);
-						failed_channels.push(chan.force_shutdown(true));
-						if let Ok(update) = self.get_channel_update_for_broadcast(&chan) {
-							pending_msg_events.push(events::MessageSendEvent::BroadcastChannelUpdate {
-								msg: update
-							});
-						}
 						self.issue_channel_close_events(chan, ClosureReason::DisconnectedPeer);
-						false
+						return false;
 					} else {
-						true
-					}
-				});
-			} else {
-				log_debug!(self.logger, "Marking channels with {} disconnected and generating channel_updates", log_pubkey!(counterparty_node_id));
-				channel_state.by_id.retain(|_, chan| {
-					if chan.get_counterparty_node_id() == *counterparty_node_id {
-						chan.remove_uncommitted_htlcs_and_mark_paused(&self.logger);
-						if chan.is_shutdown() {
-							update_maps_on_chan_removal!(self, short_to_id, chan);
-							self.issue_channel_close_events(chan, ClosureReason::DisconnectedPeer);
-							return false;
-						} else {
-							no_channels_remain = false;
-						}
+						no_channels_remain = false;
 					}
-					true
-				})
-			}
+				}
+				true
+			});
 			pending_msg_events.retain(|msg| {
 				match msg {
 					&events::MessageSendEvent::SendAcceptChannel { ref node_id, .. } => node_id != counterparty_node_id,

lightning/src/ln/functional_tests.rs

@@ -2178,9 +2178,9 @@ fn channel_monitor_network_test() {
 	send_payment(&nodes[0], &vec!(&nodes[1], &nodes[2], &nodes[3], &nodes[4])[..], 8000000);
 
 	// Simple case with no pending HTLCs:
-	nodes[1].node.peer_disconnected(&nodes[0].node.get_our_node_id(), true);
+	nodes[1].node.force_close_channel(&chan_1.2).unwrap();
 	check_added_monitors!(nodes[1], 1);
-	check_closed_broadcast!(nodes[1], false);
+	check_closed_broadcast!(nodes[1], true);
 	{
 		let mut node_txn = test_txn_broadcast(&nodes[1], &chan_1, None, HTLCType::NONE);
 		assert_eq!(node_txn.len(), 1);
@@ -2192,15 +2192,15 @@ fn channel_monitor_network_test() {
 	assert_eq!(nodes[0].node.list_channels().len(), 0);
 	assert_eq!(nodes[1].node.list_channels().len(), 1);
 	check_closed_event!(nodes[0], 1, ClosureReason::CommitmentTxConfirmed);
-	check_closed_event!(nodes[1], 1, ClosureReason::DisconnectedPeer);
+	check_closed_event!(nodes[1], 1, ClosureReason::HolderForceClosed);
 
 	// One pending HTLC is discarded by the force-close:
 	let payment_preimage_1 = route_payment(&nodes[1], &vec!(&nodes[2], &nodes[3])[..], 3000000).0;
 
 	// Simple case of one pending HTLC to HTLC-Timeout (note that the HTLC-Timeout is not
 	// broadcasted until we reach the timelock time).
-	nodes[1].node.peer_disconnected(&nodes[2].node.get_our_node_id(), true);
-	check_closed_broadcast!(nodes[1], false);
+	nodes[1].node.force_close_channel(&chan_2.2).unwrap();
+	check_closed_broadcast!(nodes[1], true);
 	check_added_monitors!(nodes[1], 1);
 	{
 		let mut node_txn = test_txn_broadcast(&nodes[1], &chan_2, None, HTLCType::NONE);
@@ -2213,7 +2213,7 @@ fn channel_monitor_network_test() {
 	check_closed_broadcast!(nodes[2], true);
 	assert_eq!(nodes[1].node.list_channels().len(), 0);
 	assert_eq!(nodes[2].node.list_channels().len(), 1);
-	check_closed_event!(nodes[1], 1, ClosureReason::DisconnectedPeer);
+	check_closed_event!(nodes[1], 1, ClosureReason::HolderForceClosed);
 	check_closed_event!(nodes[2], 1, ClosureReason::CommitmentTxConfirmed);
 
 	macro_rules! claim_funds {
@@ -2238,9 +2238,9 @@ fn channel_monitor_network_test() {
 
 	// nodes[3] gets the preimage, but nodes[2] already disconnected, resulting in a nodes[2]
 	// HTLC-Timeout and a nodes[3] claim against it (+ its own announces)
-	nodes[2].node.peer_disconnected(&nodes[3].node.get_our_node_id(), true);
+	nodes[2].node.force_close_channel(&chan_3.2).unwrap();
 	check_added_monitors!(nodes[2], 1);
-	check_closed_broadcast!(nodes[2], false);
+	check_closed_broadcast!(nodes[2], true);
 	let node2_commitment_txid;
 	{
 		let node_txn = test_txn_broadcast(&nodes[2], &chan_3, None, HTLCType::NONE);
@@ -2257,7 +2257,7 @@ fn channel_monitor_network_test() {
 	check_closed_broadcast!(nodes[3], true);
 	assert_eq!(nodes[2].node.list_channels().len(), 0);
 	assert_eq!(nodes[3].node.list_channels().len(), 1);
-	check_closed_event!(nodes[2], 1, ClosureReason::DisconnectedPeer);
+	check_closed_event!(nodes[2], 1, ClosureReason::HolderForceClosed);
 	check_closed_event!(nodes[3], 1, ClosureReason::CommitmentTxConfirmed);
 
 	// Drop the ChannelMonitor for the previous channel to avoid it broadcasting transactions and

lightning/src/ln/peer_handler.rs

@@ -258,8 +258,13 @@ pub trait SocketDescriptor : cmp::Eq + hash::Hash + Clone {
 /// descriptor.
 #[derive(Clone)]
 pub struct PeerHandleError {
-	/// Used to indicate that we probably can't make any future connections to this peer, implying
-	/// we should go ahead and force-close any channels we have with it.
+	/// Used to indicate that we probably can't make any future connections to this peer (e.g.
+	/// because we required features that our peer was missing, or vice versa).
+	///
+	/// While LDK's [`ChannelManager`] will not do it automatically, you likely wish to force-close
+	/// any channels with this peer or check for new versions of LDK.
+	///
+	/// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
 	pub no_connection_possible: bool,
 }
 impl fmt::Debug for PeerHandleError {

lightning/src/util/events.rs

@@ -100,12 +100,11 @@ pub enum ClosureReason {
 		/// A developer-readable error message which we generated.
 		err: String,
 	},
-	/// The `PeerManager` informed us that we've disconnected from the peer. We close channels
-	/// if the `PeerManager` informed us that it is unlikely we'll be able to connect to the
-	/// peer again in the future or if the peer disconnected before we finished negotiating
-	/// the channel open. The first case may be caused by incompatible features which our
-	/// counterparty, or we, require.
-	//TODO: split between PeerUnconnectable/PeerDisconnected ?
+	/// The peer disconnected prior to funding completing. In this case the spec mandates that we
+	/// forget the channel entirely - we can attempt again if the peer reconnects.
+	///
+	/// In LDK versions prior to 0.0.107 this could also occur if we were unable to connect to the
+	/// peer because of mutual incompatibility between us and our channel counterparty.
 	DisconnectedPeer,
 	/// Closure generated from `ChannelManager::read` if the ChannelMonitor is newer than
 	/// the ChannelManager deserialized.