Send bogus ChannelReestablish for unknown channels

lightning/src/ln/channel.rs

@@ -3992,7 +3992,7 @@ impl<SP: Deref> Channel<SP> where
 
  if msg.next_local_commitment_number >= INITIAL_COMMITMENT_NUMBER || msg.next_remote_commitment_number >= INITIAL_COMMITMENT_NUMBER ||
  msg.next_local_commitment_number == 0 {
- return Err(ChannelError::Close("Peer sent a garbage channel_reestablish (usually an lnd node with lost state asking us to force-close for them)".to_owned()));
+ return Err(ChannelError::Close("Peer sent an invalid channel_reestablish to force close in a non-standard way".to_owned()));
  }
 
  if msg.next_remote_commitment_number > 0 {

lightning/src/ln/channelmanager.rs

@@ -447,16 +447,17 @@ impl MsgHandleErrInternal {
 	}
 	#[inline]
 	fn from_finish_shutdown(err: String, channel_id: ChannelId, user_channel_id: u128, shutdown_res: ShutdownResult, channel_update: Option<msgs::ChannelUpdate>, channel_capacity: u64) -> Self {
+ let err_msg = msgs::ErrorMessage { channel_id, data: err.clone() };
+ let action = if let (Some(_), ..) = &shutdown_res {
+ // We have a closing `ChannelMonitorUpdate`, which means the channel was funded and we
+ // should disconnect our peer such that we force them to broadcast their latest
+ // commitment upon reconnecting.
+ msgs::ErrorAction::DisconnectPeer { msg: Some(err_msg) }
+ } else {
+ msgs::ErrorAction::SendErrorMessage { msg: err_msg }
+ };
  Self {
- err: LightningError {
- err: err.clone(),
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage {
- channel_id,
- data: err
- },
- },
- },
+ err: LightningError { err, action },
  chan_id: Some((channel_id, user_channel_id)),
  shutdown_finish: Some((shutdown_res, channel_update)),
  channel_capacity: Some(channel_capacity)
@@ -2812,8 +2813,8 @@ where
  peer_state.pending_msg_events.push(
  events::MessageSendEvent::HandleError {
  node_id: counterparty_node_id,
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage { channel_id: *channel_id, data: "Channel force-closed".to_owned() }
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage { channel_id: *channel_id, data: "Channel force-closed".to_owned() })
  },
  }
  );
@@ -4296,8 +4297,9 @@ where
  }
  }
  }
- let (counterparty_node_id, forward_chan_id) = match self.short_to_chan_info.read().unwrap().get(&short_chan_id) {
- Some((cp_id, chan_id)) => (cp_id.clone(), chan_id.clone()),
+ let chan_info_opt = self.short_to_chan_info.read().unwrap().get(&short_chan_id).cloned();
+ let (counterparty_node_id, forward_chan_id) = match chan_info_opt {
+ Some((cp_id, chan_id)) => (cp_id, chan_id),
  None => {
  forwarding_channel_not_found!();
  continue;
@@ -6785,7 +6787,10 @@ where
  let peer_state_mutex = per_peer_state.get(counterparty_node_id)
  .ok_or_else(|| {
  debug_assert!(false);
- MsgHandleErrInternal::send_err_msg_no_close(format!("Can't find a peer matching the passed counterparty node_id {}", counterparty_node_id), msg.channel_id)
+ MsgHandleErrInternal::send_err_msg_no_close(
+ format!("Can't find a peer matching the passed counterparty node_id {}", counterparty_node_id),
+ msg.channel_id
+ )
  })?;
  let mut peer_state_lock = peer_state_mutex.lock().unwrap();
  let peer_state = &mut *peer_state_lock;
@@ -6829,7 +6834,39 @@ where
  "Got a channel_reestablish message for an unfunded channel!".into())), chan_phase_entry);
  }
  },
- 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))
+ hash_map::Entry::Vacant(_) => {
+ log_debug!(self.logger, "Sending bogus ChannelReestablish for unknown channel {} to force channel closure",
+ log_bytes!(msg.channel_id.0));
+ // Unfortunately, lnd doesn't force close on errors
+ // (https://github.com/lightningnetwork/lnd/blob/abb1e3463f3a83bbb843d5c399869dbe930ad94f/htlcswitch/link.go#L2119).
+ // One of the few ways to get an lnd counterparty to force close is by
+ // replicating what they do when restoring static channel backups (SCBs). They
+ // send an invalid `ChannelReestablish` with `0` commitment numbers and an
+ // invalid `your_last_per_commitment_secret`.
+ //
+ // Since we received a `ChannelReestablish` for a channel that doesn't exist, we
+ // can assume it's likely the channel closed from our point of view, but it
+ // remains open on the counterparty's side. By sending this bogus
+ // `ChannelReestablish` message now as a response to theirs, we trigger them to
+ // force close broadcasting their latest state. If the closing transaction from
+ // our point of view remains unconfirmed, it'll enter a race with the
+ // counterparty's to-be-broadcast latest commitment transaction.
+ peer_state.pending_msg_events.push(MessageSendEvent::SendChannelReestablish {
+ node_id: *counterparty_node_id,
+ msg: msgs::ChannelReestablish {
+ channel_id: msg.channel_id,
+ next_local_commitment_number: 0,
+ next_remote_commitment_number: 0,
+ your_last_per_commitment_secret: [1u8; 32],
+ my_current_per_commitment_point: PublicKey::from_slice(&[2u8; 33]).unwrap(),
+ next_funding_txid: 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.channel_id)
+ )
+ }
  }
  };
 
@@ -6893,8 +6930,8 @@ where
  self.issue_channel_close_events(&chan.context, ClosureReason::HolderForceClosed);
  pending_msg_events.push(events::MessageSendEvent::HandleError {
  node_id: chan.context.get_counterparty_node_id(),
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage { channel_id: chan.context.channel_id(), data: "Channel force-closed".to_owned() }
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage { channel_id: chan.context.channel_id(), data: "Channel force-closed".to_owned() })
  },
  });
  }
@@ -7678,10 +7715,12 @@ where
  self.issue_channel_close_events(&channel.context, reason);
  pending_msg_events.push(events::MessageSendEvent::HandleError {
  node_id: channel.context.get_counterparty_node_id(),
- action: msgs::ErrorAction::SendErrorMessage { msg: msgs::ErrorMessage {
- channel_id: channel.context.channel_id(),
- data: reason_message,
- } },
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage {
+ channel_id: channel.context.channel_id(),
+ data: reason_message,
+ })
+ },
  });
  return false;
  }
@@ -11219,6 +11258,67 @@ mod tests {
  let payment_preimage = PaymentPreimage([42; 32]);
  assert_eq!(format!("{}", &payment_preimage), "2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a");
 	}
+
+	#[test]
+	fn test_trigger_lnd_force_close() {
+ let chanmon_cfg = create_chanmon_cfgs(2);
+ let node_cfg = create_node_cfgs(2, &chanmon_cfg);
+ let user_config = test_default_channel_config();
+ let node_chanmgr = create_node_chanmgrs(2, &node_cfg, &[Some(user_config), Some(user_config)]);
+ let nodes = create_network(2, &node_cfg, &node_chanmgr);
+
+ // Open a channel, immediately disconnect each other, and broadcast Alice's latest state.
+ let (_, _, chan_id, funding_tx) = create_announced_chan_between_nodes(&nodes, 0, 1);
+ nodes[0].node.peer_disconnected(&nodes[1].node.get_our_node_id());
+ nodes[1].node.peer_disconnected(&nodes[0].node.get_our_node_id());
+ nodes[0].node.force_close_broadcasting_latest_txn(&chan_id, &nodes[1].node.get_our_node_id()).unwrap();
+ check_closed_broadcast(&nodes[0], 1, true);
+ check_added_monitors(&nodes[0], 1);
+ check_closed_event!(nodes[0], 1, ClosureReason::HolderForceClosed, [nodes[1].node.get_our_node_id()], 100000);
+ {
+ let txn = nodes[0].tx_broadcaster.txn_broadcast();
+ assert_eq!(txn.len(), 1);
+ check_spends!(txn[0], funding_tx);
+ }
+
+ // Since they're disconnected, Bob won't receive Alice's `Error` message. Reconnect them
+ // such that Bob sends a `ChannelReestablish` to Alice since the channel is still open from
+ // their side.
+ nodes[0].node.peer_connected(&nodes[1].node.get_our_node_id(), &msgs::Init {
+ features: nodes[1].node.init_features(), networks: None, remote_network_address: None
+ }, true).unwrap();
+ nodes[1].node.peer_connected(&nodes[0].node.get_our_node_id(), &msgs::Init {
+ features: nodes[0].node.init_features(), networks: None, remote_network_address: None
+ }, false).unwrap();
+ assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
+ let channel_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(), &channel_reestablish);
+
+ // Alice should respond with an error since the channel isn't known, but a bogus
+ // `ChannelReestablish` should be sent first, such that we actually trigger Bob to force
+ // close even if it was an lnd node.
+ let msg_events = nodes[0].node.get_and_clear_pending_msg_events();
+ assert_eq!(msg_events.len(), 2);
+ if let MessageSendEvent::SendChannelReestablish { node_id, msg } = &msg_events[0] {
+ assert_eq!(*node_id, nodes[1].node.get_our_node_id());
+ assert_eq!(msg.next_local_commitment_number, 0);
+ assert_eq!(msg.next_remote_commitment_number, 0);
+ nodes[1].node.handle_channel_reestablish(&nodes[0].node.get_our_node_id(), &msg);
+ } else { panic!() };
+ check_closed_broadcast(&nodes[1], 1, true);
+ check_added_monitors(&nodes[1], 1);
+ let expected_close_reason = ClosureReason::ProcessingError {
+ err: "Peer sent an invalid channel_reestablish to force close in a non-standard way".to_string()
+ };
+ check_closed_event!(nodes[1], 1, expected_close_reason, [nodes[0].node.get_our_node_id()], 100000);
+ {
+ let txn = nodes[1].tx_broadcaster.txn_broadcast();
+ assert_eq!(txn.len(), 1);
+ check_spends!(txn[0], funding_tx);
+ }
+	}
 }
 
 #[cfg(ldk_bench)]

lightning/src/ln/functional_test_utils.rs

@@ -665,6 +665,12 @@ pub fn get_err_msg(node: &Node, recipient: &PublicKey) -> msgs::ErrorMessage {
  assert_eq!(node_id, recipient);
  (*msg).clone()
  },
+ MessageSendEvent::HandleError {
+ action: msgs::ErrorAction::DisconnectPeer { ref msg }, ref node_id
+ } => {
+ assert_eq!(node_id, recipient);
+ msg.as_ref().unwrap().clone()
+ },
  _ => panic!("Unexpected event"),
 	}
 }
@@ -1446,10 +1452,15 @@ pub fn check_closed_broadcast(node: &Node, num_channels: usize, with_error_msg:
  assert_eq!(msg.contents.flags & 2, 2);
  None
  },
- MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { ref msg }, node_id: _ } => {
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { msg }, node_id: _ } => {
  assert!(with_error_msg);
  // TODO: Check node_id
- Some(msg.clone())
+ Some(msg)
+ },
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::DisconnectPeer { msg }, node_id: _ } => {
+ assert!(with_error_msg);
+ // TODO: Check node_id
+ Some(msg.unwrap())
  },
  _ => panic!("Unexpected event"),
  }
@@ -2921,6 +2932,13 @@ pub fn handle_announce_close_broadcast_events<'a, 'b, 'c>(nodes: &Vec<Node<'a, '
  nodes[b].node.handle_error(&nodes[a].node.get_our_node_id(), msg);
  }
  },
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
+ assert_eq!(node_id, nodes[b].node.get_our_node_id());
+ assert_eq!(msg.as_ref().unwrap().data, expected_error);
+ if needs_err_handle {
+ nodes[b].node.handle_error(&nodes[a].node.get_our_node_id(), msg.as_ref().unwrap());
+ }
+ },
  _ => panic!("Unexpected event"),
 	}
 
@@ -2938,6 +2956,10 @@ pub fn handle_announce_close_broadcast_events<'a, 'b, 'c>(nodes: &Vec<Node<'a, '
  assert_eq!(node_id, nodes[a].node.get_our_node_id());
  assert_eq!(msg.data, expected_error);
  },
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
+ assert_eq!(node_id, nodes[a].node.get_our_node_id());
+ assert_eq!(msg.as_ref().unwrap().data, expected_error);
+ },
  _ => panic!("Unexpected event"),
  }
 	}

lightning/src/ln/functional_tests.rs

@@ -1338,9 +1338,9 @@ fn test_duplicate_htlc_different_direction_onchain() {
 	for e in events {
  match e {
  MessageSendEvent::BroadcastChannelUpdate { .. } => {},
- MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
- assert_eq!(msg.data, "Channel closed because commitment or closing transaction was confirmed on chain.");
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because commitment or closing transaction was confirmed on chain.");
  },
  MessageSendEvent::UpdateHTLCs { ref node_id, updates: msgs::CommitmentUpdate { ref update_add_htlcs, ref update_fulfill_htlcs, ref update_fail_htlcs, ref update_fail_malformed_htlcs, .. } } => {
  assert!(update_add_htlcs.is_empty());
@@ -2369,7 +2369,7 @@ fn channel_monitor_network_test() {
  _ => panic!("Unexpected event"),
  };
  match events[1] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id } => {
  assert_eq!(node_id, nodes[4].node.get_our_node_id());
  },
  _ => panic!("Unexpected event"),
@@ -2401,7 +2401,7 @@ fn channel_monitor_network_test() {
  _ => panic!("Unexpected event"),
  };
  match events[1] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id } => {
  assert_eq!(node_id, nodes[3].node.get_our_node_id());
  },
  _ => panic!("Unexpected event"),
@@ -2913,7 +2913,7 @@ fn test_htlc_on_chain_success() {
 	let nodes_0_event = remove_first_msg_event_to_node(&nodes[0].node.get_our_node_id(), &mut events);
 
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id: _ } => {},
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id: _ } => {},
  _ => panic!("Unexpected event"),
 	}
 
@@ -3358,7 +3358,7 @@ fn do_test_commitment_revoked_fail_backward_exhaustive(deliver_bs_raa: bool, use
 
 	let nodes_2_event = remove_first_msg_event_to_node(&nodes[2].node.get_our_node_id(), &mut events);
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { msg: msgs::ErrorMessage { channel_id, ref data } }, node_id: _ } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { msg: Some(msgs::ErrorMessage { channel_id, ref data }) }, node_id: _ } => {
  assert_eq!(channel_id, chan_2.2);
  assert_eq!(data.as_str(), "Channel closed because commitment or closing transaction was confirmed on chain.");
  },
@@ -4920,7 +4920,7 @@ fn test_onchain_to_onchain_claim() {
 	let nodes_0_event = remove_first_msg_event_to_node(&nodes[0].node.get_our_node_id(), &mut msg_events);
 
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id: _ } => {},
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id: _ } => {},
  _ => panic!("Unexpected event"),
 	}
 
@@ -7860,9 +7860,9 @@ fn test_channel_conf_timeout() {
 	let close_ev = nodes[1].node.get_and_clear_pending_msg_events();
 	assert_eq!(close_ev.len(), 1);
 	match close_ev[0] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { ref msg }, ref node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { ref msg }, ref node_id } => {
  assert_eq!(*node_id, nodes[0].node.get_our_node_id());
- assert_eq!(msg.data, "Channel closed because funding transaction failed to confirm within 2016 blocks");
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because funding transaction failed to confirm within 2016 blocks");
  },
  _ => panic!("Unexpected event"),
 	}
@@ -9212,8 +9212,8 @@ fn test_invalid_funding_tx() {
 	assert_eq!(events_2.len(), 1);
 	if let MessageSendEvent::HandleError { node_id, action } = &events_2[0] {
  assert_eq!(*node_id, nodes[0].node.get_our_node_id());
- if let msgs::ErrorAction::SendErrorMessage { msg } = action {
- assert_eq!(msg.data, "Channel closed because of an exception: ".to_owned() + expected_err);
+ if let msgs::ErrorAction::DisconnectPeer { msg } = action {
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because of an exception: ".to_owned() + expected_err);
  } else { panic!(); }
 	} else { panic!(); }
 	assert_eq!(nodes[1].node.list_channels().len(), 0);
@@ -10652,7 +10652,7 @@ fn do_test_funding_and_commitment_tx_confirm_same_block(confirm_remote_commitmen
 	let mut msg_events = closing_node.node.get_and_clear_pending_msg_events();
 	assert_eq!(msg_events.len(), 1);
 	match msg_events.pop().unwrap() {
- MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { .. }, .. } => {},
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::DisconnectPeer { .. }, .. } => {},
  _ => panic!("Unexpected event"),
 	}
 	check_added_monitors(closing_node, 1);

lightning/src/ln/payment_tests.rs

@@ -706,8 +706,8 @@ fn do_retry_with_no_persist(confirm_before_reload: bool) {
 	let bs_reestablish = get_chan_reestablish_msgs!(nodes[1], nodes[0]).pop().unwrap();
 	nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish);
 	let as_err = nodes[0].node.get_and_clear_pending_msg_events();
-	assert_eq!(as_err.len(), 1);
-	match as_err[0] {
+	assert_eq!(as_err.len(), 2);
+	match as_err[1] {
  MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
  nodes[1].node.handle_error(&nodes[0].node.get_our_node_id(), msg);
@@ -881,9 +881,9 @@ fn do_test_completed_payment_not_retryable_on_reload(use_dust: bool) {
 	let bs_reestablish = get_chan_reestablish_msgs!(nodes[1], nodes[0]).pop().unwrap();
 	nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish);
 	let as_err = nodes[0].node.get_and_clear_pending_msg_events();
-	assert_eq!(as_err.len(), 1);
+	assert_eq!(as_err.len(), 2);
 	let bs_commitment_tx;
-	match as_err[0] {
+	match as_err[1] {
  MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
  nodes[1].node.handle_error(&nodes[0].node.get_our_node_id(), msg);

lightning/src/ln/channel.rs

@@ -3992,7 +3992,7 @@ impl<SP: Deref> Channel<SP> where
 
  if msg.next_local_commitment_number >= INITIAL_COMMITMENT_NUMBER || msg.next_remote_commitment_number >= INITIAL_COMMITMENT_NUMBER ||
  msg.next_local_commitment_number == 0 {
- return Err(ChannelError::Close("Peer sent a garbage channel_reestablish (usually an lnd node with lost state asking us to force-close for them)".to_owned()));
+ return Err(ChannelError::Close("Peer sent an invalid channel_reestablish to force close in a non-standard way".to_owned()));
  }
 
  if msg.next_remote_commitment_number > 0 {

lightning/src/ln/channelmanager.rs

@@ -447,16 +447,17 @@ impl MsgHandleErrInternal {
 	}
 	#[inline]
 	fn from_finish_shutdown(err: String, channel_id: ChannelId, user_channel_id: u128, shutdown_res: ShutdownResult, channel_update: Option<msgs::ChannelUpdate>, channel_capacity: u64) -> Self {
+ let err_msg = msgs::ErrorMessage { channel_id, data: err.clone() };
+ let action = if let (Some(_), ..) = &shutdown_res {
+ // We have a closing `ChannelMonitorUpdate`, which means the channel was funded and we
+ // should disconnect our peer such that we force them to broadcast their latest
+ // commitment upon reconnecting.
+ msgs::ErrorAction::DisconnectPeer { msg: Some(err_msg) }
+ } else {
+ msgs::ErrorAction::SendErrorMessage { msg: err_msg }
+ };
  Self {
- err: LightningError {
- err: err.clone(),
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage {
- channel_id,
- data: err
- },
- },
- },
+ err: LightningError { err, action },
  chan_id: Some((channel_id, user_channel_id)),
  shutdown_finish: Some((shutdown_res, channel_update)),
  channel_capacity: Some(channel_capacity)
@@ -2812,8 +2813,8 @@ where
  peer_state.pending_msg_events.push(
  events::MessageSendEvent::HandleError {
  node_id: counterparty_node_id,
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage { channel_id: *channel_id, data: "Channel force-closed".to_owned() }
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage { channel_id: *channel_id, data: "Channel force-closed".to_owned() })
  },
  }
  );
@@ -4296,8 +4297,9 @@ where
  }
  }
  }
- let (counterparty_node_id, forward_chan_id) = match self.short_to_chan_info.read().unwrap().get(&short_chan_id) {
- Some((cp_id, chan_id)) => (cp_id.clone(), chan_id.clone()),
+ let chan_info_opt = self.short_to_chan_info.read().unwrap().get(&short_chan_id).cloned();
+ let (counterparty_node_id, forward_chan_id) = match chan_info_opt {
+ Some((cp_id, chan_id)) => (cp_id, chan_id),
  None => {
  forwarding_channel_not_found!();
  continue;
@@ -6785,7 +6787,10 @@ where
  let peer_state_mutex = per_peer_state.get(counterparty_node_id)
  .ok_or_else(|| {
  debug_assert!(false);
- MsgHandleErrInternal::send_err_msg_no_close(format!("Can't find a peer matching the passed counterparty node_id {}", counterparty_node_id), msg.channel_id)
+ MsgHandleErrInternal::send_err_msg_no_close(
+ format!("Can't find a peer matching the passed counterparty node_id {}", counterparty_node_id),
+ msg.channel_id
+ )
  })?;
  let mut peer_state_lock = peer_state_mutex.lock().unwrap();
  let peer_state = &mut *peer_state_lock;
@@ -6829,7 +6834,39 @@ where
  "Got a channel_reestablish message for an unfunded channel!".into())), chan_phase_entry);
  }
  },
- 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))
+ hash_map::Entry::Vacant(_) => {
+ log_debug!(self.logger, "Sending bogus ChannelReestablish for unknown channel {} to force channel closure",
+ log_bytes!(msg.channel_id.0));
+ // Unfortunately, lnd doesn't force close on errors
+ // (https://github.com/lightningnetwork/lnd/blob/abb1e3463f3a83bbb843d5c399869dbe930ad94f/htlcswitch/link.go#L2119).
+ // One of the few ways to get an lnd counterparty to force close is by
+ // replicating what they do when restoring static channel backups (SCBs). They
+ // send an invalid `ChannelReestablish` with `0` commitment numbers and an
+ // invalid `your_last_per_commitment_secret`.
+ //
+ // Since we received a `ChannelReestablish` for a channel that doesn't exist, we
+ // can assume it's likely the channel closed from our point of view, but it
+ // remains open on the counterparty's side. By sending this bogus
+ // `ChannelReestablish` message now as a response to theirs, we trigger them to
+ // force close broadcasting their latest state. If the closing transaction from
+ // our point of view remains unconfirmed, it'll enter a race with the
+ // counterparty's to-be-broadcast latest commitment transaction.
+ peer_state.pending_msg_events.push(MessageSendEvent::SendChannelReestablish {
+ node_id: *counterparty_node_id,
+ msg: msgs::ChannelReestablish {
+ channel_id: msg.channel_id,
+ next_local_commitment_number: 0,
+ next_remote_commitment_number: 0,
+ your_last_per_commitment_secret: [1u8; 32],
+ my_current_per_commitment_point: PublicKey::from_slice(&[2u8; 33]).unwrap(),
+ next_funding_txid: 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.channel_id)
+ )
+ }
  }
  };
 
@@ -6893,8 +6930,8 @@ where
  self.issue_channel_close_events(&chan.context, ClosureReason::HolderForceClosed);
  pending_msg_events.push(events::MessageSendEvent::HandleError {
  node_id: chan.context.get_counterparty_node_id(),
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage { channel_id: chan.context.channel_id(), data: "Channel force-closed".to_owned() }
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage { channel_id: chan.context.channel_id(), data: "Channel force-closed".to_owned() })
  },
  });
  }
@@ -7678,10 +7715,12 @@ where
  self.issue_channel_close_events(&channel.context, reason);
  pending_msg_events.push(events::MessageSendEvent::HandleError {
  node_id: channel.context.get_counterparty_node_id(),
- action: msgs::ErrorAction::SendErrorMessage { msg: msgs::ErrorMessage {
- channel_id: channel.context.channel_id(),
- data: reason_message,
- } },
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage {
+ channel_id: channel.context.channel_id(),
+ data: reason_message,
+ })
+ },
  });
  return false;
  }
@@ -11219,6 +11258,67 @@ mod tests {
  let payment_preimage = PaymentPreimage([42; 32]);
  assert_eq!(format!("{}", &payment_preimage), "2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a");
 	}
+
+	#[test]
+	fn test_trigger_lnd_force_close() {
+ let chanmon_cfg = create_chanmon_cfgs(2);
+ let node_cfg = create_node_cfgs(2, &chanmon_cfg);
+ let user_config = test_default_channel_config();
+ let node_chanmgr = create_node_chanmgrs(2, &node_cfg, &[Some(user_config), Some(user_config)]);
+ let nodes = create_network(2, &node_cfg, &node_chanmgr);
+
+ // Open a channel, immediately disconnect each other, and broadcast Alice's latest state.
+ let (_, _, chan_id, funding_tx) = create_announced_chan_between_nodes(&nodes, 0, 1);
+ nodes[0].node.peer_disconnected(&nodes[1].node.get_our_node_id());
+ nodes[1].node.peer_disconnected(&nodes[0].node.get_our_node_id());
+ nodes[0].node.force_close_broadcasting_latest_txn(&chan_id, &nodes[1].node.get_our_node_id()).unwrap();
+ check_closed_broadcast(&nodes[0], 1, true);
+ check_added_monitors(&nodes[0], 1);
+ check_closed_event!(nodes[0], 1, ClosureReason::HolderForceClosed, [nodes[1].node.get_our_node_id()], 100000);
+ {
+ let txn = nodes[0].tx_broadcaster.txn_broadcast();
+ assert_eq!(txn.len(), 1);
+ check_spends!(txn[0], funding_tx);
+ }
+
+ // Since they're disconnected, Bob won't receive Alice's `Error` message. Reconnect them
+ // such that Bob sends a `ChannelReestablish` to Alice since the channel is still open from
+ // their side.
+ nodes[0].node.peer_connected(&nodes[1].node.get_our_node_id(), &msgs::Init {
+ features: nodes[1].node.init_features(), networks: None, remote_network_address: None
+ }, true).unwrap();
+ nodes[1].node.peer_connected(&nodes[0].node.get_our_node_id(), &msgs::Init {
+ features: nodes[0].node.init_features(), networks: None, remote_network_address: None
+ }, false).unwrap();
+ assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
+ let channel_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(), &channel_reestablish);
+
+ // Alice should respond with an error since the channel isn't known, but a bogus
+ // `ChannelReestablish` should be sent first, such that we actually trigger Bob to force
+ // close even if it was an lnd node.
+ let msg_events = nodes[0].node.get_and_clear_pending_msg_events();
+ assert_eq!(msg_events.len(), 2);
+ if let MessageSendEvent::SendChannelReestablish { node_id, msg } = &msg_events[0] {
+ assert_eq!(*node_id, nodes[1].node.get_our_node_id());
+ assert_eq!(msg.next_local_commitment_number, 0);
+ assert_eq!(msg.next_remote_commitment_number, 0);
+ nodes[1].node.handle_channel_reestablish(&nodes[0].node.get_our_node_id(), &msg);
+ } else { panic!() };
+ check_closed_broadcast(&nodes[1], 1, true);
+ check_added_monitors(&nodes[1], 1);
+ let expected_close_reason = ClosureReason::ProcessingError {
+ err: "Peer sent an invalid channel_reestablish to force close in a non-standard way".to_string()
+ };
+ check_closed_event!(nodes[1], 1, expected_close_reason, [nodes[0].node.get_our_node_id()], 100000);
+ {
+ let txn = nodes[1].tx_broadcaster.txn_broadcast();
+ assert_eq!(txn.len(), 1);
+ check_spends!(txn[0], funding_tx);
+ }
+	}
 }
 
 #[cfg(ldk_bench)]

lightning/src/ln/functional_test_utils.rs

@@ -665,6 +665,12 @@ pub fn get_err_msg(node: &Node, recipient: &PublicKey) -> msgs::ErrorMessage {
  assert_eq!(node_id, recipient);
  (*msg).clone()
  },
+ MessageSendEvent::HandleError {
+ action: msgs::ErrorAction::DisconnectPeer { ref msg }, ref node_id
+ } => {
+ assert_eq!(node_id, recipient);
+ msg.as_ref().unwrap().clone()
+ },
  _ => panic!("Unexpected event"),
 	}
 }
@@ -1446,10 +1452,15 @@ pub fn check_closed_broadcast(node: &Node, num_channels: usize, with_error_msg:
  assert_eq!(msg.contents.flags & 2, 2);
  None
  },
- MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { ref msg }, node_id: _ } => {
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { msg }, node_id: _ } => {
  assert!(with_error_msg);
  // TODO: Check node_id
- Some(msg.clone())
+ Some(msg)
+ },
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::DisconnectPeer { msg }, node_id: _ } => {
+ assert!(with_error_msg);
+ // TODO: Check node_id
+ Some(msg.unwrap())
  },
  _ => panic!("Unexpected event"),
  }
@@ -2921,6 +2932,13 @@ pub fn handle_announce_close_broadcast_events<'a, 'b, 'c>(nodes: &Vec<Node<'a, '
  nodes[b].node.handle_error(&nodes[a].node.get_our_node_id(), msg);
  }
  },
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
+ assert_eq!(node_id, nodes[b].node.get_our_node_id());
+ assert_eq!(msg.as_ref().unwrap().data, expected_error);
+ if needs_err_handle {
+ nodes[b].node.handle_error(&nodes[a].node.get_our_node_id(), msg.as_ref().unwrap());
+ }
+ },
  _ => panic!("Unexpected event"),
 	}
 
@@ -2938,6 +2956,10 @@ pub fn handle_announce_close_broadcast_events<'a, 'b, 'c>(nodes: &Vec<Node<'a, '
  assert_eq!(node_id, nodes[a].node.get_our_node_id());
  assert_eq!(msg.data, expected_error);
  },
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
+ assert_eq!(node_id, nodes[a].node.get_our_node_id());
+ assert_eq!(msg.as_ref().unwrap().data, expected_error);
+ },
  _ => panic!("Unexpected event"),
  }
 	}

lightning/src/ln/functional_tests.rs

@@ -1338,9 +1338,9 @@ fn test_duplicate_htlc_different_direction_onchain() {
 	for e in events {
  match e {
  MessageSendEvent::BroadcastChannelUpdate { .. } => {},
- MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
- assert_eq!(msg.data, "Channel closed because commitment or closing transaction was confirmed on chain.");
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because commitment or closing transaction was confirmed on chain.");
  },
  MessageSendEvent::UpdateHTLCs { ref node_id, updates: msgs::CommitmentUpdate { ref update_add_htlcs, ref update_fulfill_htlcs, ref update_fail_htlcs, ref update_fail_malformed_htlcs, .. } } => {
  assert!(update_add_htlcs.is_empty());
@@ -2369,7 +2369,7 @@ fn channel_monitor_network_test() {
  _ => panic!("Unexpected event"),
  };
  match events[1] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id } => {
  assert_eq!(node_id, nodes[4].node.get_our_node_id());
  },
  _ => panic!("Unexpected event"),
@@ -2401,7 +2401,7 @@ fn channel_monitor_network_test() {
  _ => panic!("Unexpected event"),
  };
  match events[1] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id } => {
  assert_eq!(node_id, nodes[3].node.get_our_node_id());
  },
  _ => panic!("Unexpected event"),
@@ -2913,7 +2913,7 @@ fn test_htlc_on_chain_success() {
 	let nodes_0_event = remove_first_msg_event_to_node(&nodes[0].node.get_our_node_id(), &mut events);
 
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id: _ } => {},
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id: _ } => {},
  _ => panic!("Unexpected event"),
 	}
 
@@ -3358,7 +3358,7 @@ fn do_test_commitment_revoked_fail_backward_exhaustive(deliver_bs_raa: bool, use
 
 	let nodes_2_event = remove_first_msg_event_to_node(&nodes[2].node.get_our_node_id(), &mut events);
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { msg: msgs::ErrorMessage { channel_id, ref data } }, node_id: _ } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { msg: Some(msgs::ErrorMessage { channel_id, ref data }) }, node_id: _ } => {
  assert_eq!(channel_id, chan_2.2);
  assert_eq!(data.as_str(), "Channel closed because commitment or closing transaction was confirmed on chain.");
  },
@@ -4920,7 +4920,7 @@ fn test_onchain_to_onchain_claim() {
 	let nodes_0_event = remove_first_msg_event_to_node(&nodes[0].node.get_our_node_id(), &mut msg_events);
 
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id: _ } => {},
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id: _ } => {},
  _ => panic!("Unexpected event"),
 	}
 
@@ -7860,9 +7860,9 @@ fn test_channel_conf_timeout() {
 	let close_ev = nodes[1].node.get_and_clear_pending_msg_events();
 	assert_eq!(close_ev.len(), 1);
 	match close_ev[0] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { ref msg }, ref node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { ref msg }, ref node_id } => {
  assert_eq!(*node_id, nodes[0].node.get_our_node_id());
- assert_eq!(msg.data, "Channel closed because funding transaction failed to confirm within 2016 blocks");
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because funding transaction failed to confirm within 2016 blocks");
  },
  _ => panic!("Unexpected event"),
 	}
@@ -9212,8 +9212,8 @@ fn test_invalid_funding_tx() {
 	assert_eq!(events_2.len(), 1);
 	if let MessageSendEvent::HandleError { node_id, action } = &events_2[0] {
  assert_eq!(*node_id, nodes[0].node.get_our_node_id());
- if let msgs::ErrorAction::SendErrorMessage { msg } = action {
- assert_eq!(msg.data, "Channel closed because of an exception: ".to_owned() + expected_err);
+ if let msgs::ErrorAction::DisconnectPeer { msg } = action {
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because of an exception: ".to_owned() + expected_err);
  } else { panic!(); }
 	} else { panic!(); }
 	assert_eq!(nodes[1].node.list_channels().len(), 0);
@@ -10652,7 +10652,7 @@ fn do_test_funding_and_commitment_tx_confirm_same_block(confirm_remote_commitmen
 	let mut msg_events = closing_node.node.get_and_clear_pending_msg_events();
 	assert_eq!(msg_events.len(), 1);
 	match msg_events.pop().unwrap() {
- MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { .. }, .. } => {},
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::DisconnectPeer { .. }, .. } => {},
  _ => panic!("Unexpected event"),
 	}
 	check_added_monitors(closing_node, 1);

lightning/src/ln/payment_tests.rs

@@ -706,8 +706,8 @@ fn do_retry_with_no_persist(confirm_before_reload: bool) {
 	let bs_reestablish = get_chan_reestablish_msgs!(nodes[1], nodes[0]).pop().unwrap();
 	nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish);
 	let as_err = nodes[0].node.get_and_clear_pending_msg_events();
-	assert_eq!(as_err.len(), 1);
-	match as_err[0] {
+	assert_eq!(as_err.len(), 2);
+	match as_err[1] {
  MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
  nodes[1].node.handle_error(&nodes[0].node.get_our_node_id(), msg);
@@ -881,9 +881,9 @@ fn do_test_completed_payment_not_retryable_on_reload(use_dust: bool) {
 	let bs_reestablish = get_chan_reestablish_msgs!(nodes[1], nodes[0]).pop().unwrap();
 	nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish);
 	let as_err = nodes[0].node.get_and_clear_pending_msg_events();
-	assert_eq!(as_err.len(), 1);
+	assert_eq!(as_err.len(), 2);
 	let bs_commitment_tx;
-	match as_err[0] {
+	match as_err[1] {
  MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
  nodes[1].node.handle_error(&nodes[0].node.get_our_node_id(), msg);

lightning/src/ln/channel.rs

@@ -3992,7 +3992,7 @@ impl<SP: Deref> Channel<SP> where
 
  if msg.next_local_commitment_number >= INITIAL_COMMITMENT_NUMBER || msg.next_remote_commitment_number >= INITIAL_COMMITMENT_NUMBER ||
  msg.next_local_commitment_number == 0 {
- return Err(ChannelError::Close("Peer sent a garbage channel_reestablish (usually an lnd node with lost state asking us to force-close for them)".to_owned()));
+ return Err(ChannelError::Close("Peer sent an invalid channel_reestablish to force close in a non-standard way".to_owned()));
  }
 
  if msg.next_remote_commitment_number > 0 {

lightning/src/ln/channelmanager.rs

@@ -447,16 +447,17 @@ impl MsgHandleErrInternal {
 	}
 	#[inline]
 	fn from_finish_shutdown(err: String, channel_id: ChannelId, user_channel_id: u128, shutdown_res: ShutdownResult, channel_update: Option<msgs::ChannelUpdate>, channel_capacity: u64) -> Self {
+ let err_msg = msgs::ErrorMessage { channel_id, data: err.clone() };
+ let action = if let (Some(_), ..) = &shutdown_res {
+ // We have a closing `ChannelMonitorUpdate`, which means the channel was funded and we
+ // should disconnect our peer such that we force them to broadcast their latest
+ // commitment upon reconnecting.
+ msgs::ErrorAction::DisconnectPeer { msg: Some(err_msg) }
+ } else {
+ msgs::ErrorAction::SendErrorMessage { msg: err_msg }
+ };
  Self {
- err: LightningError {
- err: err.clone(),
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage {
- channel_id,
- data: err
- },
- },
- },
+ err: LightningError { err, action },
  chan_id: Some((channel_id, user_channel_id)),
  shutdown_finish: Some((shutdown_res, channel_update)),
  channel_capacity: Some(channel_capacity)
@@ -2812,8 +2813,8 @@ where
  peer_state.pending_msg_events.push(
  events::MessageSendEvent::HandleError {
  node_id: counterparty_node_id,
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage { channel_id: *channel_id, data: "Channel force-closed".to_owned() }
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage { channel_id: *channel_id, data: "Channel force-closed".to_owned() })
  },
  }
  );
@@ -4296,8 +4297,9 @@ where
  }
  }
  }
- let (counterparty_node_id, forward_chan_id) = match self.short_to_chan_info.read().unwrap().get(&short_chan_id) {
- Some((cp_id, chan_id)) => (cp_id.clone(), chan_id.clone()),
+ let chan_info_opt = self.short_to_chan_info.read().unwrap().get(&short_chan_id).cloned();
+ let (counterparty_node_id, forward_chan_id) = match chan_info_opt {
+ Some((cp_id, chan_id)) => (cp_id, chan_id),
  None => {
  forwarding_channel_not_found!();
  continue;
@@ -6785,7 +6787,10 @@ where
  let peer_state_mutex = per_peer_state.get(counterparty_node_id)
  .ok_or_else(|| {
  debug_assert!(false);
- MsgHandleErrInternal::send_err_msg_no_close(format!("Can't find a peer matching the passed counterparty node_id {}", counterparty_node_id), msg.channel_id)
+ MsgHandleErrInternal::send_err_msg_no_close(
+ format!("Can't find a peer matching the passed counterparty node_id {}", counterparty_node_id),
+ msg.channel_id
+ )
  })?;
  let mut peer_state_lock = peer_state_mutex.lock().unwrap();
  let peer_state = &mut *peer_state_lock;
@@ -6829,7 +6834,39 @@ where
  "Got a channel_reestablish message for an unfunded channel!".into())), chan_phase_entry);
  }
  },
- 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))
+ hash_map::Entry::Vacant(_) => {
+ log_debug!(self.logger, "Sending bogus ChannelReestablish for unknown channel {} to force channel closure",
+ log_bytes!(msg.channel_id.0));
+ // Unfortunately, lnd doesn't force close on errors
+ // (https://github.com/lightningnetwork/lnd/blob/abb1e3463f3a83bbb843d5c399869dbe930ad94f/htlcswitch/link.go#L2119).
+ // One of the few ways to get an lnd counterparty to force close is by
+ // replicating what they do when restoring static channel backups (SCBs). They
+ // send an invalid `ChannelReestablish` with `0` commitment numbers and an
+ // invalid `your_last_per_commitment_secret`.
+ //
+ // Since we received a `ChannelReestablish` for a channel that doesn't exist, we
+ // can assume it's likely the channel closed from our point of view, but it
+ // remains open on the counterparty's side. By sending this bogus
+ // `ChannelReestablish` message now as a response to theirs, we trigger them to
+ // force close broadcasting their latest state. If the closing transaction from
+ // our point of view remains unconfirmed, it'll enter a race with the
+ // counterparty's to-be-broadcast latest commitment transaction.
+ peer_state.pending_msg_events.push(MessageSendEvent::SendChannelReestablish {
+ node_id: *counterparty_node_id,
+ msg: msgs::ChannelReestablish {
+ channel_id: msg.channel_id,
+ next_local_commitment_number: 0,
+ next_remote_commitment_number: 0,
+ your_last_per_commitment_secret: [1u8; 32],
+ my_current_per_commitment_point: PublicKey::from_slice(&[2u8; 33]).unwrap(),
+ next_funding_txid: 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.channel_id)
+ )
+ }
  }
  };
 
@@ -6893,8 +6930,8 @@ where
  self.issue_channel_close_events(&chan.context, ClosureReason::HolderForceClosed);
  pending_msg_events.push(events::MessageSendEvent::HandleError {
  node_id: chan.context.get_counterparty_node_id(),
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage { channel_id: chan.context.channel_id(), data: "Channel force-closed".to_owned() }
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage { channel_id: chan.context.channel_id(), data: "Channel force-closed".to_owned() })
  },
  });
  }
@@ -7678,10 +7715,12 @@ where
  self.issue_channel_close_events(&channel.context, reason);
  pending_msg_events.push(events::MessageSendEvent::HandleError {
  node_id: channel.context.get_counterparty_node_id(),
- action: msgs::ErrorAction::SendErrorMessage { msg: msgs::ErrorMessage {
- channel_id: channel.context.channel_id(),
- data: reason_message,
- } },
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage {
+ channel_id: channel.context.channel_id(),
+ data: reason_message,
+ })
+ },
  });
  return false;
  }
@@ -11219,6 +11258,67 @@ mod tests {
  let payment_preimage = PaymentPreimage([42; 32]);
  assert_eq!(format!("{}", &payment_preimage), "2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a");
 	}
+
+	#[test]
+	fn test_trigger_lnd_force_close() {
+ let chanmon_cfg = create_chanmon_cfgs(2);
+ let node_cfg = create_node_cfgs(2, &chanmon_cfg);
+ let user_config = test_default_channel_config();
+ let node_chanmgr = create_node_chanmgrs(2, &node_cfg, &[Some(user_config), Some(user_config)]);
+ let nodes = create_network(2, &node_cfg, &node_chanmgr);
+
+ // Open a channel, immediately disconnect each other, and broadcast Alice's latest state.
+ let (_, _, chan_id, funding_tx) = create_announced_chan_between_nodes(&nodes, 0, 1);
+ nodes[0].node.peer_disconnected(&nodes[1].node.get_our_node_id());
+ nodes[1].node.peer_disconnected(&nodes[0].node.get_our_node_id());
+ nodes[0].node.force_close_broadcasting_latest_txn(&chan_id, &nodes[1].node.get_our_node_id()).unwrap();
+ check_closed_broadcast(&nodes[0], 1, true);
+ check_added_monitors(&nodes[0], 1);
+ check_closed_event!(nodes[0], 1, ClosureReason::HolderForceClosed, [nodes[1].node.get_our_node_id()], 100000);
+ {
+ let txn = nodes[0].tx_broadcaster.txn_broadcast();
+ assert_eq!(txn.len(), 1);
+ check_spends!(txn[0], funding_tx);
+ }
+
+ // Since they're disconnected, Bob won't receive Alice's `Error` message. Reconnect them
+ // such that Bob sends a `ChannelReestablish` to Alice since the channel is still open from
+ // their side.
+ nodes[0].node.peer_connected(&nodes[1].node.get_our_node_id(), &msgs::Init {
+ features: nodes[1].node.init_features(), networks: None, remote_network_address: None
+ }, true).unwrap();
+ nodes[1].node.peer_connected(&nodes[0].node.get_our_node_id(), &msgs::Init {
+ features: nodes[0].node.init_features(), networks: None, remote_network_address: None
+ }, false).unwrap();
+ assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
+ let channel_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(), &channel_reestablish);
+
+ // Alice should respond with an error since the channel isn't known, but a bogus
+ // `ChannelReestablish` should be sent first, such that we actually trigger Bob to force
+ // close even if it was an lnd node.
+ let msg_events = nodes[0].node.get_and_clear_pending_msg_events();
+ assert_eq!(msg_events.len(), 2);
+ if let MessageSendEvent::SendChannelReestablish { node_id, msg } = &msg_events[0] {
+ assert_eq!(*node_id, nodes[1].node.get_our_node_id());
+ assert_eq!(msg.next_local_commitment_number, 0);
+ assert_eq!(msg.next_remote_commitment_number, 0);
+ nodes[1].node.handle_channel_reestablish(&nodes[0].node.get_our_node_id(), &msg);
+ } else { panic!() };
+ check_closed_broadcast(&nodes[1], 1, true);
+ check_added_monitors(&nodes[1], 1);
+ let expected_close_reason = ClosureReason::ProcessingError {
+ err: "Peer sent an invalid channel_reestablish to force close in a non-standard way".to_string()
+ };
+ check_closed_event!(nodes[1], 1, expected_close_reason, [nodes[0].node.get_our_node_id()], 100000);
+ {
+ let txn = nodes[1].tx_broadcaster.txn_broadcast();
+ assert_eq!(txn.len(), 1);
+ check_spends!(txn[0], funding_tx);
+ }
+	}
 }
 
 #[cfg(ldk_bench)]

lightning/src/ln/functional_test_utils.rs

@@ -665,6 +665,12 @@ pub fn get_err_msg(node: &Node, recipient: &PublicKey) -> msgs::ErrorMessage {
  assert_eq!(node_id, recipient);
  (*msg).clone()
  },
+ MessageSendEvent::HandleError {
+ action: msgs::ErrorAction::DisconnectPeer { ref msg }, ref node_id
+ } => {
+ assert_eq!(node_id, recipient);
+ msg.as_ref().unwrap().clone()
+ },
  _ => panic!("Unexpected event"),
 	}
 }
@@ -1446,10 +1452,15 @@ pub fn check_closed_broadcast(node: &Node, num_channels: usize, with_error_msg:
  assert_eq!(msg.contents.flags & 2, 2);
  None
  },
- MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { ref msg }, node_id: _ } => {
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { msg }, node_id: _ } => {
  assert!(with_error_msg);
  // TODO: Check node_id
- Some(msg.clone())
+ Some(msg)
+ },
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::DisconnectPeer { msg }, node_id: _ } => {
+ assert!(with_error_msg);
+ // TODO: Check node_id
+ Some(msg.unwrap())
  },
  _ => panic!("Unexpected event"),
  }
@@ -2921,6 +2932,13 @@ pub fn handle_announce_close_broadcast_events<'a, 'b, 'c>(nodes: &Vec<Node<'a, '
  nodes[b].node.handle_error(&nodes[a].node.get_our_node_id(), msg);
  }
  },
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
+ assert_eq!(node_id, nodes[b].node.get_our_node_id());
+ assert_eq!(msg.as_ref().unwrap().data, expected_error);
+ if needs_err_handle {
+ nodes[b].node.handle_error(&nodes[a].node.get_our_node_id(), msg.as_ref().unwrap());
+ }
+ },
  _ => panic!("Unexpected event"),
 	}
 
@@ -2938,6 +2956,10 @@ pub fn handle_announce_close_broadcast_events<'a, 'b, 'c>(nodes: &Vec<Node<'a, '
  assert_eq!(node_id, nodes[a].node.get_our_node_id());
  assert_eq!(msg.data, expected_error);
  },
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
+ assert_eq!(node_id, nodes[a].node.get_our_node_id());
+ assert_eq!(msg.as_ref().unwrap().data, expected_error);
+ },
  _ => panic!("Unexpected event"),
  }
 	}

lightning/src/ln/functional_tests.rs

@@ -1338,9 +1338,9 @@ fn test_duplicate_htlc_different_direction_onchain() {
 	for e in events {
  match e {
  MessageSendEvent::BroadcastChannelUpdate { .. } => {},
- MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
- assert_eq!(msg.data, "Channel closed because commitment or closing transaction was confirmed on chain.");
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because commitment or closing transaction was confirmed on chain.");
  },
  MessageSendEvent::UpdateHTLCs { ref node_id, updates: msgs::CommitmentUpdate { ref update_add_htlcs, ref update_fulfill_htlcs, ref update_fail_htlcs, ref update_fail_malformed_htlcs, .. } } => {
  assert!(update_add_htlcs.is_empty());
@@ -2369,7 +2369,7 @@ fn channel_monitor_network_test() {
  _ => panic!("Unexpected event"),
  };
  match events[1] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id } => {
  assert_eq!(node_id, nodes[4].node.get_our_node_id());
  },
  _ => panic!("Unexpected event"),
@@ -2401,7 +2401,7 @@ fn channel_monitor_network_test() {
  _ => panic!("Unexpected event"),
  };
  match events[1] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id } => {
  assert_eq!(node_id, nodes[3].node.get_our_node_id());
  },
  _ => panic!("Unexpected event"),
@@ -2913,7 +2913,7 @@ fn test_htlc_on_chain_success() {
 	let nodes_0_event = remove_first_msg_event_to_node(&nodes[0].node.get_our_node_id(), &mut events);
 
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id: _ } => {},
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id: _ } => {},
  _ => panic!("Unexpected event"),
 	}
 
@@ -3358,7 +3358,7 @@ fn do_test_commitment_revoked_fail_backward_exhaustive(deliver_bs_raa: bool, use
 
 	let nodes_2_event = remove_first_msg_event_to_node(&nodes[2].node.get_our_node_id(), &mut events);
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { msg: msgs::ErrorMessage { channel_id, ref data } }, node_id: _ } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { msg: Some(msgs::ErrorMessage { channel_id, ref data }) }, node_id: _ } => {
  assert_eq!(channel_id, chan_2.2);
  assert_eq!(data.as_str(), "Channel closed because commitment or closing transaction was confirmed on chain.");
  },
@@ -4920,7 +4920,7 @@ fn test_onchain_to_onchain_claim() {
 	let nodes_0_event = remove_first_msg_event_to_node(&nodes[0].node.get_our_node_id(), &mut msg_events);
 
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id: _ } => {},
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id: _ } => {},
  _ => panic!("Unexpected event"),
 	}
 
@@ -7860,9 +7860,9 @@ fn test_channel_conf_timeout() {
 	let close_ev = nodes[1].node.get_and_clear_pending_msg_events();
 	assert_eq!(close_ev.len(), 1);
 	match close_ev[0] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { ref msg }, ref node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { ref msg }, ref node_id } => {
  assert_eq!(*node_id, nodes[0].node.get_our_node_id());
- assert_eq!(msg.data, "Channel closed because funding transaction failed to confirm within 2016 blocks");
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because funding transaction failed to confirm within 2016 blocks");
  },
  _ => panic!("Unexpected event"),
 	}
@@ -9212,8 +9212,8 @@ fn test_invalid_funding_tx() {
 	assert_eq!(events_2.len(), 1);
 	if let MessageSendEvent::HandleError { node_id, action } = &events_2[0] {
  assert_eq!(*node_id, nodes[0].node.get_our_node_id());
- if let msgs::ErrorAction::SendErrorMessage { msg } = action {
- assert_eq!(msg.data, "Channel closed because of an exception: ".to_owned() + expected_err);
+ if let msgs::ErrorAction::DisconnectPeer { msg } = action {
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because of an exception: ".to_owned() + expected_err);
  } else { panic!(); }
 	} else { panic!(); }
 	assert_eq!(nodes[1].node.list_channels().len(), 0);
@@ -10652,7 +10652,7 @@ fn do_test_funding_and_commitment_tx_confirm_same_block(confirm_remote_commitmen
 	let mut msg_events = closing_node.node.get_and_clear_pending_msg_events();
 	assert_eq!(msg_events.len(), 1);
 	match msg_events.pop().unwrap() {
- MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { .. }, .. } => {},
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::DisconnectPeer { .. }, .. } => {},
  _ => panic!("Unexpected event"),
 	}
 	check_added_monitors(closing_node, 1);

lightning/src/ln/payment_tests.rs

@@ -706,8 +706,8 @@ fn do_retry_with_no_persist(confirm_before_reload: bool) {
 	let bs_reestablish = get_chan_reestablish_msgs!(nodes[1], nodes[0]).pop().unwrap();
 	nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish);
 	let as_err = nodes[0].node.get_and_clear_pending_msg_events();
-	assert_eq!(as_err.len(), 1);
-	match as_err[0] {
+	assert_eq!(as_err.len(), 2);
+	match as_err[1] {
  MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
  nodes[1].node.handle_error(&nodes[0].node.get_our_node_id(), msg);
@@ -881,9 +881,9 @@ fn do_test_completed_payment_not_retryable_on_reload(use_dust: bool) {
 	let bs_reestablish = get_chan_reestablish_msgs!(nodes[1], nodes[0]).pop().unwrap();
 	nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish);
 	let as_err = nodes[0].node.get_and_clear_pending_msg_events();
-	assert_eq!(as_err.len(), 1);
+	assert_eq!(as_err.len(), 2);
 	let bs_commitment_tx;
-	match as_err[0] {
+	match as_err[1] {
  MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
  nodes[1].node.handle_error(&nodes[0].node.get_our_node_id(), msg);

lightning/src/ln/channel.rs

@@ -3992,7 +3992,7 @@ impl<SP: Deref> Channel<SP> where
 
  if msg.next_local_commitment_number >= INITIAL_COMMITMENT_NUMBER || msg.next_remote_commitment_number >= INITIAL_COMMITMENT_NUMBER ||
  msg.next_local_commitment_number == 0 {
- return Err(ChannelError::Close("Peer sent a garbage channel_reestablish (usually an lnd node with lost state asking us to force-close for them)".to_owned()));
+ return Err(ChannelError::Close("Peer sent an invalid channel_reestablish to force close in a non-standard way".to_owned()));
  }
 
  if msg.next_remote_commitment_number > 0 {

lightning/src/ln/channelmanager.rs

@@ -447,16 +447,17 @@ impl MsgHandleErrInternal {
 	}
 	#[inline]
 	fn from_finish_shutdown(err: String, channel_id: ChannelId, user_channel_id: u128, shutdown_res: ShutdownResult, channel_update: Option<msgs::ChannelUpdate>, channel_capacity: u64) -> Self {
+ let err_msg = msgs::ErrorMessage { channel_id, data: err.clone() };
+ let action = if let (Some(_), ..) = &shutdown_res {
+ // We have a closing `ChannelMonitorUpdate`, which means the channel was funded and we
+ // should disconnect our peer such that we force them to broadcast their latest
+ // commitment upon reconnecting.
+ msgs::ErrorAction::DisconnectPeer { msg: Some(err_msg) }
+ } else {
+ msgs::ErrorAction::SendErrorMessage { msg: err_msg }
+ };
  Self {
- err: LightningError {
- err: err.clone(),
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage {
- channel_id,
- data: err
- },
- },
- },
+ err: LightningError { err, action },
  chan_id: Some((channel_id, user_channel_id)),
  shutdown_finish: Some((shutdown_res, channel_update)),
  channel_capacity: Some(channel_capacity)
@@ -2812,8 +2813,8 @@ where
  peer_state.pending_msg_events.push(
  events::MessageSendEvent::HandleError {
  node_id: counterparty_node_id,
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage { channel_id: *channel_id, data: "Channel force-closed".to_owned() }
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage { channel_id: *channel_id, data: "Channel force-closed".to_owned() })
  },
  }
  );
@@ -4296,8 +4297,9 @@ where
  }
  }
  }
- let (counterparty_node_id, forward_chan_id) = match self.short_to_chan_info.read().unwrap().get(&short_chan_id) {
- Some((cp_id, chan_id)) => (cp_id.clone(), chan_id.clone()),
+ let chan_info_opt = self.short_to_chan_info.read().unwrap().get(&short_chan_id).cloned();
+ let (counterparty_node_id, forward_chan_id) = match chan_info_opt {
+ Some((cp_id, chan_id)) => (cp_id, chan_id),
  None => {
  forwarding_channel_not_found!();
  continue;
@@ -6785,7 +6787,10 @@ where
  let peer_state_mutex = per_peer_state.get(counterparty_node_id)
  .ok_or_else(|| {
  debug_assert!(false);
- MsgHandleErrInternal::send_err_msg_no_close(format!("Can't find a peer matching the passed counterparty node_id {}", counterparty_node_id), msg.channel_id)
+ MsgHandleErrInternal::send_err_msg_no_close(
+ format!("Can't find a peer matching the passed counterparty node_id {}", counterparty_node_id),
+ msg.channel_id
+ )
  })?;
  let mut peer_state_lock = peer_state_mutex.lock().unwrap();
  let peer_state = &mut *peer_state_lock;
@@ -6829,7 +6834,39 @@ where
  "Got a channel_reestablish message for an unfunded channel!".into())), chan_phase_entry);
  }
  },
- 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))
+ hash_map::Entry::Vacant(_) => {
+ log_debug!(self.logger, "Sending bogus ChannelReestablish for unknown channel {} to force channel closure",
+ log_bytes!(msg.channel_id.0));
+ // Unfortunately, lnd doesn't force close on errors
+ // (https://github.com/lightningnetwork/lnd/blob/abb1e3463f3a83bbb843d5c399869dbe930ad94f/htlcswitch/link.go#L2119).
+ // One of the few ways to get an lnd counterparty to force close is by
+ // replicating what they do when restoring static channel backups (SCBs). They
+ // send an invalid `ChannelReestablish` with `0` commitment numbers and an
+ // invalid `your_last_per_commitment_secret`.
+ //
+ // Since we received a `ChannelReestablish` for a channel that doesn't exist, we
+ // can assume it's likely the channel closed from our point of view, but it
+ // remains open on the counterparty's side. By sending this bogus
+ // `ChannelReestablish` message now as a response to theirs, we trigger them to
+ // force close broadcasting their latest state. If the closing transaction from
+ // our point of view remains unconfirmed, it'll enter a race with the
+ // counterparty's to-be-broadcast latest commitment transaction.
+ peer_state.pending_msg_events.push(MessageSendEvent::SendChannelReestablish {
+ node_id: *counterparty_node_id,
+ msg: msgs::ChannelReestablish {
+ channel_id: msg.channel_id,
+ next_local_commitment_number: 0,
+ next_remote_commitment_number: 0,
+ your_last_per_commitment_secret: [1u8; 32],
+ my_current_per_commitment_point: PublicKey::from_slice(&[2u8; 33]).unwrap(),
+ next_funding_txid: 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.channel_id)
+ )
+ }
  }
  };
 
@@ -6893,8 +6930,8 @@ where
  self.issue_channel_close_events(&chan.context, ClosureReason::HolderForceClosed);
  pending_msg_events.push(events::MessageSendEvent::HandleError {
  node_id: chan.context.get_counterparty_node_id(),
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage { channel_id: chan.context.channel_id(), data: "Channel force-closed".to_owned() }
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage { channel_id: chan.context.channel_id(), data: "Channel force-closed".to_owned() })
  },
  });
  }
@@ -7678,10 +7715,12 @@ where
  self.issue_channel_close_events(&channel.context, reason);
  pending_msg_events.push(events::MessageSendEvent::HandleError {
  node_id: channel.context.get_counterparty_node_id(),
- action: msgs::ErrorAction::SendErrorMessage { msg: msgs::ErrorMessage {
- channel_id: channel.context.channel_id(),
- data: reason_message,
- } },
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage {
+ channel_id: channel.context.channel_id(),
+ data: reason_message,
+ })
+ },
  });
  return false;
  }
@@ -11219,6 +11258,67 @@ mod tests {
  let payment_preimage = PaymentPreimage([42; 32]);
  assert_eq!(format!("{}", &payment_preimage), "2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a");
 	}
+
+	#[test]
+	fn test_trigger_lnd_force_close() {
+ let chanmon_cfg = create_chanmon_cfgs(2);
+ let node_cfg = create_node_cfgs(2, &chanmon_cfg);
+ let user_config = test_default_channel_config();
+ let node_chanmgr = create_node_chanmgrs(2, &node_cfg, &[Some(user_config), Some(user_config)]);
+ let nodes = create_network(2, &node_cfg, &node_chanmgr);
+
+ // Open a channel, immediately disconnect each other, and broadcast Alice's latest state.
+ let (_, _, chan_id, funding_tx) = create_announced_chan_between_nodes(&nodes, 0, 1);
+ nodes[0].node.peer_disconnected(&nodes[1].node.get_our_node_id());
+ nodes[1].node.peer_disconnected(&nodes[0].node.get_our_node_id());
+ nodes[0].node.force_close_broadcasting_latest_txn(&chan_id, &nodes[1].node.get_our_node_id()).unwrap();
+ check_closed_broadcast(&nodes[0], 1, true);
+ check_added_monitors(&nodes[0], 1);
+ check_closed_event!(nodes[0], 1, ClosureReason::HolderForceClosed, [nodes[1].node.get_our_node_id()], 100000);
+ {
+ let txn = nodes[0].tx_broadcaster.txn_broadcast();
+ assert_eq!(txn.len(), 1);
+ check_spends!(txn[0], funding_tx);
+ }
+
+ // Since they're disconnected, Bob won't receive Alice's `Error` message. Reconnect them
+ // such that Bob sends a `ChannelReestablish` to Alice since the channel is still open from
+ // their side.
+ nodes[0].node.peer_connected(&nodes[1].node.get_our_node_id(), &msgs::Init {
+ features: nodes[1].node.init_features(), networks: None, remote_network_address: None
+ }, true).unwrap();
+ nodes[1].node.peer_connected(&nodes[0].node.get_our_node_id(), &msgs::Init {
+ features: nodes[0].node.init_features(), networks: None, remote_network_address: None
+ }, false).unwrap();
+ assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
+ let channel_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(), &channel_reestablish);
+
+ // Alice should respond with an error since the channel isn't known, but a bogus
+ // `ChannelReestablish` should be sent first, such that we actually trigger Bob to force
+ // close even if it was an lnd node.
+ let msg_events = nodes[0].node.get_and_clear_pending_msg_events();
+ assert_eq!(msg_events.len(), 2);
+ if let MessageSendEvent::SendChannelReestablish { node_id, msg } = &msg_events[0] {
+ assert_eq!(*node_id, nodes[1].node.get_our_node_id());
+ assert_eq!(msg.next_local_commitment_number, 0);
+ assert_eq!(msg.next_remote_commitment_number, 0);
+ nodes[1].node.handle_channel_reestablish(&nodes[0].node.get_our_node_id(), &msg);
+ } else { panic!() };
+ check_closed_broadcast(&nodes[1], 1, true);
+ check_added_monitors(&nodes[1], 1);
+ let expected_close_reason = ClosureReason::ProcessingError {
+ err: "Peer sent an invalid channel_reestablish to force close in a non-standard way".to_string()
+ };
+ check_closed_event!(nodes[1], 1, expected_close_reason, [nodes[0].node.get_our_node_id()], 100000);
+ {
+ let txn = nodes[1].tx_broadcaster.txn_broadcast();
+ assert_eq!(txn.len(), 1);
+ check_spends!(txn[0], funding_tx);
+ }
+	}
 }
 
 #[cfg(ldk_bench)]

lightning/src/ln/functional_test_utils.rs

@@ -665,6 +665,12 @@ pub fn get_err_msg(node: &Node, recipient: &PublicKey) -> msgs::ErrorMessage {
  assert_eq!(node_id, recipient);
  (*msg).clone()
  },
+ MessageSendEvent::HandleError {
+ action: msgs::ErrorAction::DisconnectPeer { ref msg }, ref node_id
+ } => {
+ assert_eq!(node_id, recipient);
+ msg.as_ref().unwrap().clone()
+ },
  _ => panic!("Unexpected event"),
 	}
 }
@@ -1446,10 +1452,15 @@ pub fn check_closed_broadcast(node: &Node, num_channels: usize, with_error_msg:
  assert_eq!(msg.contents.flags & 2, 2);
  None
  },
- MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { ref msg }, node_id: _ } => {
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { msg }, node_id: _ } => {
  assert!(with_error_msg);
  // TODO: Check node_id
- Some(msg.clone())
+ Some(msg)
+ },
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::DisconnectPeer { msg }, node_id: _ } => {
+ assert!(with_error_msg);
+ // TODO: Check node_id
+ Some(msg.unwrap())
  },
  _ => panic!("Unexpected event"),
  }
@@ -2921,6 +2932,13 @@ pub fn handle_announce_close_broadcast_events<'a, 'b, 'c>(nodes: &Vec<Node<'a, '
  nodes[b].node.handle_error(&nodes[a].node.get_our_node_id(), msg);
  }
  },
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
+ assert_eq!(node_id, nodes[b].node.get_our_node_id());
+ assert_eq!(msg.as_ref().unwrap().data, expected_error);
+ if needs_err_handle {
+ nodes[b].node.handle_error(&nodes[a].node.get_our_node_id(), msg.as_ref().unwrap());
+ }
+ },
  _ => panic!("Unexpected event"),
 	}
 
@@ -2938,6 +2956,10 @@ pub fn handle_announce_close_broadcast_events<'a, 'b, 'c>(nodes: &Vec<Node<'a, '
  assert_eq!(node_id, nodes[a].node.get_our_node_id());
  assert_eq!(msg.data, expected_error);
  },
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
+ assert_eq!(node_id, nodes[a].node.get_our_node_id());
+ assert_eq!(msg.as_ref().unwrap().data, expected_error);
+ },
  _ => panic!("Unexpected event"),
  }
 	}

lightning/src/ln/functional_tests.rs

@@ -1338,9 +1338,9 @@ fn test_duplicate_htlc_different_direction_onchain() {
 	for e in events {
  match e {
  MessageSendEvent::BroadcastChannelUpdate { .. } => {},
- MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
- assert_eq!(msg.data, "Channel closed because commitment or closing transaction was confirmed on chain.");
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because commitment or closing transaction was confirmed on chain.");
  },
  MessageSendEvent::UpdateHTLCs { ref node_id, updates: msgs::CommitmentUpdate { ref update_add_htlcs, ref update_fulfill_htlcs, ref update_fail_htlcs, ref update_fail_malformed_htlcs, .. } } => {
  assert!(update_add_htlcs.is_empty());
@@ -2369,7 +2369,7 @@ fn channel_monitor_network_test() {
  _ => panic!("Unexpected event"),
  };
  match events[1] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id } => {
  assert_eq!(node_id, nodes[4].node.get_our_node_id());
  },
  _ => panic!("Unexpected event"),
@@ -2401,7 +2401,7 @@ fn channel_monitor_network_test() {
  _ => panic!("Unexpected event"),
  };
  match events[1] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id } => {
  assert_eq!(node_id, nodes[3].node.get_our_node_id());
  },
  _ => panic!("Unexpected event"),
@@ -2913,7 +2913,7 @@ fn test_htlc_on_chain_success() {
 	let nodes_0_event = remove_first_msg_event_to_node(&nodes[0].node.get_our_node_id(), &mut events);
 
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id: _ } => {},
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id: _ } => {},
  _ => panic!("Unexpected event"),
 	}
 
@@ -3358,7 +3358,7 @@ fn do_test_commitment_revoked_fail_backward_exhaustive(deliver_bs_raa: bool, use
 
 	let nodes_2_event = remove_first_msg_event_to_node(&nodes[2].node.get_our_node_id(), &mut events);
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { msg: msgs::ErrorMessage { channel_id, ref data } }, node_id: _ } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { msg: Some(msgs::ErrorMessage { channel_id, ref data }) }, node_id: _ } => {
  assert_eq!(channel_id, chan_2.2);
  assert_eq!(data.as_str(), "Channel closed because commitment or closing transaction was confirmed on chain.");
  },
@@ -4920,7 +4920,7 @@ fn test_onchain_to_onchain_claim() {
 	let nodes_0_event = remove_first_msg_event_to_node(&nodes[0].node.get_our_node_id(), &mut msg_events);
 
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id: _ } => {},
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id: _ } => {},
  _ => panic!("Unexpected event"),
 	}
 
@@ -7860,9 +7860,9 @@ fn test_channel_conf_timeout() {
 	let close_ev = nodes[1].node.get_and_clear_pending_msg_events();
 	assert_eq!(close_ev.len(), 1);
 	match close_ev[0] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { ref msg }, ref node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { ref msg }, ref node_id } => {
  assert_eq!(*node_id, nodes[0].node.get_our_node_id());
- assert_eq!(msg.data, "Channel closed because funding transaction failed to confirm within 2016 blocks");
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because funding transaction failed to confirm within 2016 blocks");
  },
  _ => panic!("Unexpected event"),
 	}
@@ -9212,8 +9212,8 @@ fn test_invalid_funding_tx() {
 	assert_eq!(events_2.len(), 1);
 	if let MessageSendEvent::HandleError { node_id, action } = &events_2[0] {
  assert_eq!(*node_id, nodes[0].node.get_our_node_id());
- if let msgs::ErrorAction::SendErrorMessage { msg } = action {
- assert_eq!(msg.data, "Channel closed because of an exception: ".to_owned() + expected_err);
+ if let msgs::ErrorAction::DisconnectPeer { msg } = action {
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because of an exception: ".to_owned() + expected_err);
  } else { panic!(); }
 	} else { panic!(); }
 	assert_eq!(nodes[1].node.list_channels().len(), 0);
@@ -10652,7 +10652,7 @@ fn do_test_funding_and_commitment_tx_confirm_same_block(confirm_remote_commitmen
 	let mut msg_events = closing_node.node.get_and_clear_pending_msg_events();
 	assert_eq!(msg_events.len(), 1);
 	match msg_events.pop().unwrap() {
- MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { .. }, .. } => {},
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::DisconnectPeer { .. }, .. } => {},
  _ => panic!("Unexpected event"),
 	}
 	check_added_monitors(closing_node, 1);

lightning/src/ln/payment_tests.rs

@@ -706,8 +706,8 @@ fn do_retry_with_no_persist(confirm_before_reload: bool) {
 	let bs_reestablish = get_chan_reestablish_msgs!(nodes[1], nodes[0]).pop().unwrap();
 	nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish);
 	let as_err = nodes[0].node.get_and_clear_pending_msg_events();
-	assert_eq!(as_err.len(), 1);
-	match as_err[0] {
+	assert_eq!(as_err.len(), 2);
+	match as_err[1] {
  MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
  nodes[1].node.handle_error(&nodes[0].node.get_our_node_id(), msg);
@@ -881,9 +881,9 @@ fn do_test_completed_payment_not_retryable_on_reload(use_dust: bool) {
 	let bs_reestablish = get_chan_reestablish_msgs!(nodes[1], nodes[0]).pop().unwrap();
 	nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish);
 	let as_err = nodes[0].node.get_and_clear_pending_msg_events();
-	assert_eq!(as_err.len(), 1);
+	assert_eq!(as_err.len(), 2);
 	let bs_commitment_tx;
-	match as_err[0] {
+	match as_err[1] {
  MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
  nodes[1].node.handle_error(&nodes[0].node.get_our_node_id(), msg);

lightning/src/ln/channel.rs

@@ -3992,7 +3992,7 @@ impl<SP: Deref> Channel<SP> where
 
  if msg.next_local_commitment_number >= INITIAL_COMMITMENT_NUMBER || msg.next_remote_commitment_number >= INITIAL_COMMITMENT_NUMBER ||
  msg.next_local_commitment_number == 0 {
- return Err(ChannelError::Close("Peer sent a garbage channel_reestablish (usually an lnd node with lost state asking us to force-close for them)".to_owned()));
+ return Err(ChannelError::Close("Peer sent an invalid channel_reestablish to force close in a non-standard way".to_owned()));
  }
 
  if msg.next_remote_commitment_number > 0 {

lightning/src/ln/channelmanager.rs

@@ -447,16 +447,17 @@ impl MsgHandleErrInternal {
 	}
 	#[inline]
 	fn from_finish_shutdown(err: String, channel_id: ChannelId, user_channel_id: u128, shutdown_res: ShutdownResult, channel_update: Option<msgs::ChannelUpdate>, channel_capacity: u64) -> Self {
+ let err_msg = msgs::ErrorMessage { channel_id, data: err.clone() };
+ let action = if let (Some(_), ..) = &shutdown_res {
+ // We have a closing `ChannelMonitorUpdate`, which means the channel was funded and we
+ // should disconnect our peer such that we force them to broadcast their latest
+ // commitment upon reconnecting.
+ msgs::ErrorAction::DisconnectPeer { msg: Some(err_msg) }
+ } else {
+ msgs::ErrorAction::SendErrorMessage { msg: err_msg }
+ };
  Self {
- err: LightningError {
- err: err.clone(),
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage {
- channel_id,
- data: err
- },
- },
- },
+ err: LightningError { err, action },
  chan_id: Some((channel_id, user_channel_id)),
  shutdown_finish: Some((shutdown_res, channel_update)),
  channel_capacity: Some(channel_capacity)
@@ -2812,8 +2813,8 @@ where
  peer_state.pending_msg_events.push(
  events::MessageSendEvent::HandleError {
  node_id: counterparty_node_id,
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage { channel_id: *channel_id, data: "Channel force-closed".to_owned() }
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage { channel_id: *channel_id, data: "Channel force-closed".to_owned() })
  },
  }
  );
@@ -4296,8 +4297,9 @@ where
  }
  }
  }
- let (counterparty_node_id, forward_chan_id) = match self.short_to_chan_info.read().unwrap().get(&short_chan_id) {
- Some((cp_id, chan_id)) => (cp_id.clone(), chan_id.clone()),
+ let chan_info_opt = self.short_to_chan_info.read().unwrap().get(&short_chan_id).cloned();
+ let (counterparty_node_id, forward_chan_id) = match chan_info_opt {
+ Some((cp_id, chan_id)) => (cp_id, chan_id),
  None => {
  forwarding_channel_not_found!();
  continue;
@@ -6785,7 +6787,10 @@ where
  let peer_state_mutex = per_peer_state.get(counterparty_node_id)
  .ok_or_else(|| {
  debug_assert!(false);
- MsgHandleErrInternal::send_err_msg_no_close(format!("Can't find a peer matching the passed counterparty node_id {}", counterparty_node_id), msg.channel_id)
+ MsgHandleErrInternal::send_err_msg_no_close(
+ format!("Can't find a peer matching the passed counterparty node_id {}", counterparty_node_id),
+ msg.channel_id
+ )
  })?;
  let mut peer_state_lock = peer_state_mutex.lock().unwrap();
  let peer_state = &mut *peer_state_lock;
@@ -6829,7 +6834,39 @@ where
  "Got a channel_reestablish message for an unfunded channel!".into())), chan_phase_entry);
  }
  },
- 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))
+ hash_map::Entry::Vacant(_) => {
+ log_debug!(self.logger, "Sending bogus ChannelReestablish for unknown channel {} to force channel closure",
+ log_bytes!(msg.channel_id.0));
+ // Unfortunately, lnd doesn't force close on errors
+ // (https://github.com/lightningnetwork/lnd/blob/abb1e3463f3a83bbb843d5c399869dbe930ad94f/htlcswitch/link.go#L2119).
+ // One of the few ways to get an lnd counterparty to force close is by
+ // replicating what they do when restoring static channel backups (SCBs). They
+ // send an invalid `ChannelReestablish` with `0` commitment numbers and an
+ // invalid `your_last_per_commitment_secret`.
+ //
+ // Since we received a `ChannelReestablish` for a channel that doesn't exist, we
+ // can assume it's likely the channel closed from our point of view, but it
+ // remains open on the counterparty's side. By sending this bogus
+ // `ChannelReestablish` message now as a response to theirs, we trigger them to
+ // force close broadcasting their latest state. If the closing transaction from
+ // our point of view remains unconfirmed, it'll enter a race with the
+ // counterparty's to-be-broadcast latest commitment transaction.
+ peer_state.pending_msg_events.push(MessageSendEvent::SendChannelReestablish {
+ node_id: *counterparty_node_id,
+ msg: msgs::ChannelReestablish {
+ channel_id: msg.channel_id,
+ next_local_commitment_number: 0,
+ next_remote_commitment_number: 0,
+ your_last_per_commitment_secret: [1u8; 32],
+ my_current_per_commitment_point: PublicKey::from_slice(&[2u8; 33]).unwrap(),
+ next_funding_txid: 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.channel_id)
+ )
+ }
  }
  };
 
@@ -6893,8 +6930,8 @@ where
  self.issue_channel_close_events(&chan.context, ClosureReason::HolderForceClosed);
  pending_msg_events.push(events::MessageSendEvent::HandleError {
  node_id: chan.context.get_counterparty_node_id(),
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage { channel_id: chan.context.channel_id(), data: "Channel force-closed".to_owned() }
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage { channel_id: chan.context.channel_id(), data: "Channel force-closed".to_owned() })
  },
  });
  }
@@ -7678,10 +7715,12 @@ where
  self.issue_channel_close_events(&channel.context, reason);
  pending_msg_events.push(events::MessageSendEvent::HandleError {
  node_id: channel.context.get_counterparty_node_id(),
- action: msgs::ErrorAction::SendErrorMessage { msg: msgs::ErrorMessage {
- channel_id: channel.context.channel_id(),
- data: reason_message,
- } },
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage {
+ channel_id: channel.context.channel_id(),
+ data: reason_message,
+ })
+ },
  });
  return false;
  }
@@ -11219,6 +11258,67 @@ mod tests {
  let payment_preimage = PaymentPreimage([42; 32]);
  assert_eq!(format!("{}", &payment_preimage), "2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a");
 	}
+
+	#[test]
+	fn test_trigger_lnd_force_close() {
+ let chanmon_cfg = create_chanmon_cfgs(2);
+ let node_cfg = create_node_cfgs(2, &chanmon_cfg);
+ let user_config = test_default_channel_config();
+ let node_chanmgr = create_node_chanmgrs(2, &node_cfg, &[Some(user_config), Some(user_config)]);
+ let nodes = create_network(2, &node_cfg, &node_chanmgr);
+
+ // Open a channel, immediately disconnect each other, and broadcast Alice's latest state.
+ let (_, _, chan_id, funding_tx) = create_announced_chan_between_nodes(&nodes, 0, 1);
+ nodes[0].node.peer_disconnected(&nodes[1].node.get_our_node_id());
+ nodes[1].node.peer_disconnected(&nodes[0].node.get_our_node_id());
+ nodes[0].node.force_close_broadcasting_latest_txn(&chan_id, &nodes[1].node.get_our_node_id()).unwrap();
+ check_closed_broadcast(&nodes[0], 1, true);
+ check_added_monitors(&nodes[0], 1);
+ check_closed_event!(nodes[0], 1, ClosureReason::HolderForceClosed, [nodes[1].node.get_our_node_id()], 100000);
+ {
+ let txn = nodes[0].tx_broadcaster.txn_broadcast();
+ assert_eq!(txn.len(), 1);
+ check_spends!(txn[0], funding_tx);
+ }
+
+ // Since they're disconnected, Bob won't receive Alice's `Error` message. Reconnect them
+ // such that Bob sends a `ChannelReestablish` to Alice since the channel is still open from
+ // their side.
+ nodes[0].node.peer_connected(&nodes[1].node.get_our_node_id(), &msgs::Init {
+ features: nodes[1].node.init_features(), networks: None, remote_network_address: None
+ }, true).unwrap();
+ nodes[1].node.peer_connected(&nodes[0].node.get_our_node_id(), &msgs::Init {
+ features: nodes[0].node.init_features(), networks: None, remote_network_address: None
+ }, false).unwrap();
+ assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
+ let channel_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(), &channel_reestablish);
+
+ // Alice should respond with an error since the channel isn't known, but a bogus
+ // `ChannelReestablish` should be sent first, such that we actually trigger Bob to force
+ // close even if it was an lnd node.
+ let msg_events = nodes[0].node.get_and_clear_pending_msg_events();
+ assert_eq!(msg_events.len(), 2);
+ if let MessageSendEvent::SendChannelReestablish { node_id, msg } = &msg_events[0] {
+ assert_eq!(*node_id, nodes[1].node.get_our_node_id());
+ assert_eq!(msg.next_local_commitment_number, 0);
+ assert_eq!(msg.next_remote_commitment_number, 0);
+ nodes[1].node.handle_channel_reestablish(&nodes[0].node.get_our_node_id(), &msg);
+ } else { panic!() };
+ check_closed_broadcast(&nodes[1], 1, true);
+ check_added_monitors(&nodes[1], 1);
+ let expected_close_reason = ClosureReason::ProcessingError {
+ err: "Peer sent an invalid channel_reestablish to force close in a non-standard way".to_string()
+ };
+ check_closed_event!(nodes[1], 1, expected_close_reason, [nodes[0].node.get_our_node_id()], 100000);
+ {
+ let txn = nodes[1].tx_broadcaster.txn_broadcast();
+ assert_eq!(txn.len(), 1);
+ check_spends!(txn[0], funding_tx);
+ }
+	}
 }
 
 #[cfg(ldk_bench)]

lightning/src/ln/functional_test_utils.rs

@@ -665,6 +665,12 @@ pub fn get_err_msg(node: &Node, recipient: &PublicKey) -> msgs::ErrorMessage {
  assert_eq!(node_id, recipient);
  (*msg).clone()
  },
+ MessageSendEvent::HandleError {
+ action: msgs::ErrorAction::DisconnectPeer { ref msg }, ref node_id
+ } => {
+ assert_eq!(node_id, recipient);
+ msg.as_ref().unwrap().clone()
+ },
  _ => panic!("Unexpected event"),
 	}
 }
@@ -1446,10 +1452,15 @@ pub fn check_closed_broadcast(node: &Node, num_channels: usize, with_error_msg:
  assert_eq!(msg.contents.flags & 2, 2);
  None
  },
- MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { ref msg }, node_id: _ } => {
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { msg }, node_id: _ } => {
  assert!(with_error_msg);
  // TODO: Check node_id
- Some(msg.clone())
+ Some(msg)
+ },
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::DisconnectPeer { msg }, node_id: _ } => {
+ assert!(with_error_msg);
+ // TODO: Check node_id
+ Some(msg.unwrap())
  },
  _ => panic!("Unexpected event"),
  }
@@ -2921,6 +2932,13 @@ pub fn handle_announce_close_broadcast_events<'a, 'b, 'c>(nodes: &Vec<Node<'a, '
  nodes[b].node.handle_error(&nodes[a].node.get_our_node_id(), msg);
  }
  },
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
+ assert_eq!(node_id, nodes[b].node.get_our_node_id());
+ assert_eq!(msg.as_ref().unwrap().data, expected_error);
+ if needs_err_handle {
+ nodes[b].node.handle_error(&nodes[a].node.get_our_node_id(), msg.as_ref().unwrap());
+ }
+ },
  _ => panic!("Unexpected event"),
 	}
 
@@ -2938,6 +2956,10 @@ pub fn handle_announce_close_broadcast_events<'a, 'b, 'c>(nodes: &Vec<Node<'a, '
  assert_eq!(node_id, nodes[a].node.get_our_node_id());
  assert_eq!(msg.data, expected_error);
  },
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
+ assert_eq!(node_id, nodes[a].node.get_our_node_id());
+ assert_eq!(msg.as_ref().unwrap().data, expected_error);
+ },
  _ => panic!("Unexpected event"),
  }
 	}

lightning/src/ln/functional_tests.rs

@@ -1338,9 +1338,9 @@ fn test_duplicate_htlc_different_direction_onchain() {
 	for e in events {
  match e {
  MessageSendEvent::BroadcastChannelUpdate { .. } => {},
- MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
- assert_eq!(msg.data, "Channel closed because commitment or closing transaction was confirmed on chain.");
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because commitment or closing transaction was confirmed on chain.");
  },
  MessageSendEvent::UpdateHTLCs { ref node_id, updates: msgs::CommitmentUpdate { ref update_add_htlcs, ref update_fulfill_htlcs, ref update_fail_htlcs, ref update_fail_malformed_htlcs, .. } } => {
  assert!(update_add_htlcs.is_empty());
@@ -2369,7 +2369,7 @@ fn channel_monitor_network_test() {
  _ => panic!("Unexpected event"),
  };
  match events[1] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id } => {
  assert_eq!(node_id, nodes[4].node.get_our_node_id());
  },
  _ => panic!("Unexpected event"),
@@ -2401,7 +2401,7 @@ fn channel_monitor_network_test() {
  _ => panic!("Unexpected event"),
  };
  match events[1] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id } => {
  assert_eq!(node_id, nodes[3].node.get_our_node_id());
  },
  _ => panic!("Unexpected event"),
@@ -2913,7 +2913,7 @@ fn test_htlc_on_chain_success() {
 	let nodes_0_event = remove_first_msg_event_to_node(&nodes[0].node.get_our_node_id(), &mut events);
 
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id: _ } => {},
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id: _ } => {},
  _ => panic!("Unexpected event"),
 	}
 
@@ -3358,7 +3358,7 @@ fn do_test_commitment_revoked_fail_backward_exhaustive(deliver_bs_raa: bool, use
 
 	let nodes_2_event = remove_first_msg_event_to_node(&nodes[2].node.get_our_node_id(), &mut events);
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { msg: msgs::ErrorMessage { channel_id, ref data } }, node_id: _ } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { msg: Some(msgs::ErrorMessage { channel_id, ref data }) }, node_id: _ } => {
  assert_eq!(channel_id, chan_2.2);
  assert_eq!(data.as_str(), "Channel closed because commitment or closing transaction was confirmed on chain.");
  },
@@ -4920,7 +4920,7 @@ fn test_onchain_to_onchain_claim() {
 	let nodes_0_event = remove_first_msg_event_to_node(&nodes[0].node.get_our_node_id(), &mut msg_events);
 
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id: _ } => {},
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id: _ } => {},
  _ => panic!("Unexpected event"),
 	}
 
@@ -7860,9 +7860,9 @@ fn test_channel_conf_timeout() {
 	let close_ev = nodes[1].node.get_and_clear_pending_msg_events();
 	assert_eq!(close_ev.len(), 1);
 	match close_ev[0] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { ref msg }, ref node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { ref msg }, ref node_id } => {
  assert_eq!(*node_id, nodes[0].node.get_our_node_id());
- assert_eq!(msg.data, "Channel closed because funding transaction failed to confirm within 2016 blocks");
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because funding transaction failed to confirm within 2016 blocks");
  },
  _ => panic!("Unexpected event"),
 	}
@@ -9212,8 +9212,8 @@ fn test_invalid_funding_tx() {
 	assert_eq!(events_2.len(), 1);
 	if let MessageSendEvent::HandleError { node_id, action } = &events_2[0] {
  assert_eq!(*node_id, nodes[0].node.get_our_node_id());
- if let msgs::ErrorAction::SendErrorMessage { msg } = action {
- assert_eq!(msg.data, "Channel closed because of an exception: ".to_owned() + expected_err);
+ if let msgs::ErrorAction::DisconnectPeer { msg } = action {
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because of an exception: ".to_owned() + expected_err);
  } else { panic!(); }
 	} else { panic!(); }
 	assert_eq!(nodes[1].node.list_channels().len(), 0);
@@ -10652,7 +10652,7 @@ fn do_test_funding_and_commitment_tx_confirm_same_block(confirm_remote_commitmen
 	let mut msg_events = closing_node.node.get_and_clear_pending_msg_events();
 	assert_eq!(msg_events.len(), 1);
 	match msg_events.pop().unwrap() {
- MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { .. }, .. } => {},
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::DisconnectPeer { .. }, .. } => {},
  _ => panic!("Unexpected event"),
 	}
 	check_added_monitors(closing_node, 1);

lightning/src/ln/payment_tests.rs

@@ -706,8 +706,8 @@ fn do_retry_with_no_persist(confirm_before_reload: bool) {
 	let bs_reestablish = get_chan_reestablish_msgs!(nodes[1], nodes[0]).pop().unwrap();
 	nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish);
 	let as_err = nodes[0].node.get_and_clear_pending_msg_events();
-	assert_eq!(as_err.len(), 1);
-	match as_err[0] {
+	assert_eq!(as_err.len(), 2);
+	match as_err[1] {
  MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
  nodes[1].node.handle_error(&nodes[0].node.get_our_node_id(), msg);
@@ -881,9 +881,9 @@ fn do_test_completed_payment_not_retryable_on_reload(use_dust: bool) {
 	let bs_reestablish = get_chan_reestablish_msgs!(nodes[1], nodes[0]).pop().unwrap();
 	nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish);
 	let as_err = nodes[0].node.get_and_clear_pending_msg_events();
-	assert_eq!(as_err.len(), 1);
+	assert_eq!(as_err.len(), 2);
 	let bs_commitment_tx;
-	match as_err[0] {
+	match as_err[1] {
  MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
  nodes[1].node.handle_error(&nodes[0].node.get_our_node_id(), msg);

lightning/src/ln/channel.rs

@@ -3992,7 +3992,7 @@ impl<SP: Deref> Channel<SP> where
 
  if msg.next_local_commitment_number >= INITIAL_COMMITMENT_NUMBER || msg.next_remote_commitment_number >= INITIAL_COMMITMENT_NUMBER ||
  msg.next_local_commitment_number == 0 {
- return Err(ChannelError::Close("Peer sent a garbage channel_reestablish (usually an lnd node with lost state asking us to force-close for them)".to_owned()));
+ return Err(ChannelError::Close("Peer sent an invalid channel_reestablish to force close in a non-standard way".to_owned()));
  }
 
  if msg.next_remote_commitment_number > 0 {

lightning/src/ln/channelmanager.rs

@@ -447,16 +447,17 @@ impl MsgHandleErrInternal {
 	}
 	#[inline]
 	fn from_finish_shutdown(err: String, channel_id: ChannelId, user_channel_id: u128, shutdown_res: ShutdownResult, channel_update: Option<msgs::ChannelUpdate>, channel_capacity: u64) -> Self {
+ let err_msg = msgs::ErrorMessage { channel_id, data: err.clone() };
+ let action = if let (Some(_), ..) = &shutdown_res {
+ // We have a closing `ChannelMonitorUpdate`, which means the channel was funded and we
+ // should disconnect our peer such that we force them to broadcast their latest
+ // commitment upon reconnecting.
+ msgs::ErrorAction::DisconnectPeer { msg: Some(err_msg) }
+ } else {
+ msgs::ErrorAction::SendErrorMessage { msg: err_msg }
+ };
  Self {
- err: LightningError {
- err: err.clone(),
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage {
- channel_id,
- data: err
- },
- },
- },
+ err: LightningError { err, action },
  chan_id: Some((channel_id, user_channel_id)),
  shutdown_finish: Some((shutdown_res, channel_update)),
  channel_capacity: Some(channel_capacity)
@@ -2812,8 +2813,8 @@ where
  peer_state.pending_msg_events.push(
  events::MessageSendEvent::HandleError {
  node_id: counterparty_node_id,
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage { channel_id: *channel_id, data: "Channel force-closed".to_owned() }
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage { channel_id: *channel_id, data: "Channel force-closed".to_owned() })
  },
  }
  );
@@ -4296,8 +4297,9 @@ where
  }
  }
  }
- let (counterparty_node_id, forward_chan_id) = match self.short_to_chan_info.read().unwrap().get(&short_chan_id) {
- Some((cp_id, chan_id)) => (cp_id.clone(), chan_id.clone()),
+ let chan_info_opt = self.short_to_chan_info.read().unwrap().get(&short_chan_id).cloned();
+ let (counterparty_node_id, forward_chan_id) = match chan_info_opt {
+ Some((cp_id, chan_id)) => (cp_id, chan_id),
  None => {
  forwarding_channel_not_found!();
  continue;
@@ -6785,7 +6787,10 @@ where
  let peer_state_mutex = per_peer_state.get(counterparty_node_id)
  .ok_or_else(|| {
  debug_assert!(false);
- MsgHandleErrInternal::send_err_msg_no_close(format!("Can't find a peer matching the passed counterparty node_id {}", counterparty_node_id), msg.channel_id)
+ MsgHandleErrInternal::send_err_msg_no_close(
+ format!("Can't find a peer matching the passed counterparty node_id {}", counterparty_node_id),
+ msg.channel_id
+ )
  })?;
  let mut peer_state_lock = peer_state_mutex.lock().unwrap();
  let peer_state = &mut *peer_state_lock;
@@ -6829,7 +6834,39 @@ where
  "Got a channel_reestablish message for an unfunded channel!".into())), chan_phase_entry);
  }
  },
- 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))
+ hash_map::Entry::Vacant(_) => {
+ log_debug!(self.logger, "Sending bogus ChannelReestablish for unknown channel {} to force channel closure",
+ log_bytes!(msg.channel_id.0));
+ // Unfortunately, lnd doesn't force close on errors
+ // (https://github.com/lightningnetwork/lnd/blob/abb1e3463f3a83bbb843d5c399869dbe930ad94f/htlcswitch/link.go#L2119).
+ // One of the few ways to get an lnd counterparty to force close is by
+ // replicating what they do when restoring static channel backups (SCBs). They
+ // send an invalid `ChannelReestablish` with `0` commitment numbers and an
+ // invalid `your_last_per_commitment_secret`.
+ //
+ // Since we received a `ChannelReestablish` for a channel that doesn't exist, we
+ // can assume it's likely the channel closed from our point of view, but it
+ // remains open on the counterparty's side. By sending this bogus
+ // `ChannelReestablish` message now as a response to theirs, we trigger them to
+ // force close broadcasting their latest state. If the closing transaction from
+ // our point of view remains unconfirmed, it'll enter a race with the
+ // counterparty's to-be-broadcast latest commitment transaction.
+ peer_state.pending_msg_events.push(MessageSendEvent::SendChannelReestablish {
+ node_id: *counterparty_node_id,
+ msg: msgs::ChannelReestablish {
+ channel_id: msg.channel_id,
+ next_local_commitment_number: 0,
+ next_remote_commitment_number: 0,
+ your_last_per_commitment_secret: [1u8; 32],
+ my_current_per_commitment_point: PublicKey::from_slice(&[2u8; 33]).unwrap(),
+ next_funding_txid: 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.channel_id)
+ )
+ }
  }
  };
 
@@ -6893,8 +6930,8 @@ where
  self.issue_channel_close_events(&chan.context, ClosureReason::HolderForceClosed);
  pending_msg_events.push(events::MessageSendEvent::HandleError {
  node_id: chan.context.get_counterparty_node_id(),
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage { channel_id: chan.context.channel_id(), data: "Channel force-closed".to_owned() }
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage { channel_id: chan.context.channel_id(), data: "Channel force-closed".to_owned() })
  },
  });
  }
@@ -7678,10 +7715,12 @@ where
  self.issue_channel_close_events(&channel.context, reason);
  pending_msg_events.push(events::MessageSendEvent::HandleError {
  node_id: channel.context.get_counterparty_node_id(),
- action: msgs::ErrorAction::SendErrorMessage { msg: msgs::ErrorMessage {
- channel_id: channel.context.channel_id(),
- data: reason_message,
- } },
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage {
+ channel_id: channel.context.channel_id(),
+ data: reason_message,
+ })
+ },
  });
  return false;
  }
@@ -11219,6 +11258,67 @@ mod tests {
  let payment_preimage = PaymentPreimage([42; 32]);
  assert_eq!(format!("{}", &payment_preimage), "2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a");
 	}
+
+	#[test]
+	fn test_trigger_lnd_force_close() {
+ let chanmon_cfg = create_chanmon_cfgs(2);
+ let node_cfg = create_node_cfgs(2, &chanmon_cfg);
+ let user_config = test_default_channel_config();
+ let node_chanmgr = create_node_chanmgrs(2, &node_cfg, &[Some(user_config), Some(user_config)]);
+ let nodes = create_network(2, &node_cfg, &node_chanmgr);
+
+ // Open a channel, immediately disconnect each other, and broadcast Alice's latest state.
+ let (_, _, chan_id, funding_tx) = create_announced_chan_between_nodes(&nodes, 0, 1);
+ nodes[0].node.peer_disconnected(&nodes[1].node.get_our_node_id());
+ nodes[1].node.peer_disconnected(&nodes[0].node.get_our_node_id());
+ nodes[0].node.force_close_broadcasting_latest_txn(&chan_id, &nodes[1].node.get_our_node_id()).unwrap();
+ check_closed_broadcast(&nodes[0], 1, true);
+ check_added_monitors(&nodes[0], 1);
+ check_closed_event!(nodes[0], 1, ClosureReason::HolderForceClosed, [nodes[1].node.get_our_node_id()], 100000);
+ {
+ let txn = nodes[0].tx_broadcaster.txn_broadcast();
+ assert_eq!(txn.len(), 1);
+ check_spends!(txn[0], funding_tx);
+ }
+
+ // Since they're disconnected, Bob won't receive Alice's `Error` message. Reconnect them
+ // such that Bob sends a `ChannelReestablish` to Alice since the channel is still open from
+ // their side.
+ nodes[0].node.peer_connected(&nodes[1].node.get_our_node_id(), &msgs::Init {
+ features: nodes[1].node.init_features(), networks: None, remote_network_address: None
+ }, true).unwrap();
+ nodes[1].node.peer_connected(&nodes[0].node.get_our_node_id(), &msgs::Init {
+ features: nodes[0].node.init_features(), networks: None, remote_network_address: None
+ }, false).unwrap();
+ assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
+ let channel_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(), &channel_reestablish);
+
+ // Alice should respond with an error since the channel isn't known, but a bogus
+ // `ChannelReestablish` should be sent first, such that we actually trigger Bob to force
+ // close even if it was an lnd node.
+ let msg_events = nodes[0].node.get_and_clear_pending_msg_events();
+ assert_eq!(msg_events.len(), 2);
+ if let MessageSendEvent::SendChannelReestablish { node_id, msg } = &msg_events[0] {
+ assert_eq!(*node_id, nodes[1].node.get_our_node_id());
+ assert_eq!(msg.next_local_commitment_number, 0);
+ assert_eq!(msg.next_remote_commitment_number, 0);
+ nodes[1].node.handle_channel_reestablish(&nodes[0].node.get_our_node_id(), &msg);
+ } else { panic!() };
+ check_closed_broadcast(&nodes[1], 1, true);
+ check_added_monitors(&nodes[1], 1);
+ let expected_close_reason = ClosureReason::ProcessingError {
+ err: "Peer sent an invalid channel_reestablish to force close in a non-standard way".to_string()
+ };
+ check_closed_event!(nodes[1], 1, expected_close_reason, [nodes[0].node.get_our_node_id()], 100000);
+ {
+ let txn = nodes[1].tx_broadcaster.txn_broadcast();
+ assert_eq!(txn.len(), 1);
+ check_spends!(txn[0], funding_tx);
+ }
+	}
 }
 
 #[cfg(ldk_bench)]

lightning/src/ln/functional_test_utils.rs

@@ -665,6 +665,12 @@ pub fn get_err_msg(node: &Node, recipient: &PublicKey) -> msgs::ErrorMessage {
  assert_eq!(node_id, recipient);
  (*msg).clone()
  },
+ MessageSendEvent::HandleError {
+ action: msgs::ErrorAction::DisconnectPeer { ref msg }, ref node_id
+ } => {
+ assert_eq!(node_id, recipient);
+ msg.as_ref().unwrap().clone()
+ },
  _ => panic!("Unexpected event"),
 	}
 }
@@ -1446,10 +1452,15 @@ pub fn check_closed_broadcast(node: &Node, num_channels: usize, with_error_msg:
  assert_eq!(msg.contents.flags & 2, 2);
  None
  },
- MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { ref msg }, node_id: _ } => {
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { msg }, node_id: _ } => {
  assert!(with_error_msg);
  // TODO: Check node_id
- Some(msg.clone())
+ Some(msg)
+ },
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::DisconnectPeer { msg }, node_id: _ } => {
+ assert!(with_error_msg);
+ // TODO: Check node_id
+ Some(msg.unwrap())
  },
  _ => panic!("Unexpected event"),
  }
@@ -2921,6 +2932,13 @@ pub fn handle_announce_close_broadcast_events<'a, 'b, 'c>(nodes: &Vec<Node<'a, '
  nodes[b].node.handle_error(&nodes[a].node.get_our_node_id(), msg);
  }
  },
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
+ assert_eq!(node_id, nodes[b].node.get_our_node_id());
+ assert_eq!(msg.as_ref().unwrap().data, expected_error);
+ if needs_err_handle {
+ nodes[b].node.handle_error(&nodes[a].node.get_our_node_id(), msg.as_ref().unwrap());
+ }
+ },
  _ => panic!("Unexpected event"),
 	}
 
@@ -2938,6 +2956,10 @@ pub fn handle_announce_close_broadcast_events<'a, 'b, 'c>(nodes: &Vec<Node<'a, '
  assert_eq!(node_id, nodes[a].node.get_our_node_id());
  assert_eq!(msg.data, expected_error);
  },
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
+ assert_eq!(node_id, nodes[a].node.get_our_node_id());
+ assert_eq!(msg.as_ref().unwrap().data, expected_error);
+ },
  _ => panic!("Unexpected event"),
  }
 	}

lightning/src/ln/functional_tests.rs

@@ -1338,9 +1338,9 @@ fn test_duplicate_htlc_different_direction_onchain() {
 	for e in events {
  match e {
  MessageSendEvent::BroadcastChannelUpdate { .. } => {},
- MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
- assert_eq!(msg.data, "Channel closed because commitment or closing transaction was confirmed on chain.");
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because commitment or closing transaction was confirmed on chain.");
  },
  MessageSendEvent::UpdateHTLCs { ref node_id, updates: msgs::CommitmentUpdate { ref update_add_htlcs, ref update_fulfill_htlcs, ref update_fail_htlcs, ref update_fail_malformed_htlcs, .. } } => {
  assert!(update_add_htlcs.is_empty());
@@ -2369,7 +2369,7 @@ fn channel_monitor_network_test() {
  _ => panic!("Unexpected event"),
  };
  match events[1] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id } => {
  assert_eq!(node_id, nodes[4].node.get_our_node_id());
  },
  _ => panic!("Unexpected event"),
@@ -2401,7 +2401,7 @@ fn channel_monitor_network_test() {
  _ => panic!("Unexpected event"),
  };
  match events[1] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id } => {
  assert_eq!(node_id, nodes[3].node.get_our_node_id());
  },
  _ => panic!("Unexpected event"),
@@ -2913,7 +2913,7 @@ fn test_htlc_on_chain_success() {
 	let nodes_0_event = remove_first_msg_event_to_node(&nodes[0].node.get_our_node_id(), &mut events);
 
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id: _ } => {},
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id: _ } => {},
  _ => panic!("Unexpected event"),
 	}
 
@@ -3358,7 +3358,7 @@ fn do_test_commitment_revoked_fail_backward_exhaustive(deliver_bs_raa: bool, use
 
 	let nodes_2_event = remove_first_msg_event_to_node(&nodes[2].node.get_our_node_id(), &mut events);
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { msg: msgs::ErrorMessage { channel_id, ref data } }, node_id: _ } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { msg: Some(msgs::ErrorMessage { channel_id, ref data }) }, node_id: _ } => {
  assert_eq!(channel_id, chan_2.2);
  assert_eq!(data.as_str(), "Channel closed because commitment or closing transaction was confirmed on chain.");
  },
@@ -4920,7 +4920,7 @@ fn test_onchain_to_onchain_claim() {
 	let nodes_0_event = remove_first_msg_event_to_node(&nodes[0].node.get_our_node_id(), &mut msg_events);
 
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id: _ } => {},
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id: _ } => {},
  _ => panic!("Unexpected event"),
 	}
 
@@ -7860,9 +7860,9 @@ fn test_channel_conf_timeout() {
 	let close_ev = nodes[1].node.get_and_clear_pending_msg_events();
 	assert_eq!(close_ev.len(), 1);
 	match close_ev[0] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { ref msg }, ref node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { ref msg }, ref node_id } => {
  assert_eq!(*node_id, nodes[0].node.get_our_node_id());
- assert_eq!(msg.data, "Channel closed because funding transaction failed to confirm within 2016 blocks");
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because funding transaction failed to confirm within 2016 blocks");
  },
  _ => panic!("Unexpected event"),
 	}
@@ -9212,8 +9212,8 @@ fn test_invalid_funding_tx() {
 	assert_eq!(events_2.len(), 1);
 	if let MessageSendEvent::HandleError { node_id, action } = &events_2[0] {
  assert_eq!(*node_id, nodes[0].node.get_our_node_id());
- if let msgs::ErrorAction::SendErrorMessage { msg } = action {
- assert_eq!(msg.data, "Channel closed because of an exception: ".to_owned() + expected_err);
+ if let msgs::ErrorAction::DisconnectPeer { msg } = action {
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because of an exception: ".to_owned() + expected_err);
  } else { panic!(); }
 	} else { panic!(); }
 	assert_eq!(nodes[1].node.list_channels().len(), 0);
@@ -10652,7 +10652,7 @@ fn do_test_funding_and_commitment_tx_confirm_same_block(confirm_remote_commitmen
 	let mut msg_events = closing_node.node.get_and_clear_pending_msg_events();
 	assert_eq!(msg_events.len(), 1);
 	match msg_events.pop().unwrap() {
- MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { .. }, .. } => {},
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::DisconnectPeer { .. }, .. } => {},
  _ => panic!("Unexpected event"),
 	}
 	check_added_monitors(closing_node, 1);

lightning/src/ln/payment_tests.rs

@@ -706,8 +706,8 @@ fn do_retry_with_no_persist(confirm_before_reload: bool) {
 	let bs_reestablish = get_chan_reestablish_msgs!(nodes[1], nodes[0]).pop().unwrap();
 	nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish);
 	let as_err = nodes[0].node.get_and_clear_pending_msg_events();
-	assert_eq!(as_err.len(), 1);
-	match as_err[0] {
+	assert_eq!(as_err.len(), 2);
+	match as_err[1] {
  MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
  nodes[1].node.handle_error(&nodes[0].node.get_our_node_id(), msg);
@@ -881,9 +881,9 @@ fn do_test_completed_payment_not_retryable_on_reload(use_dust: bool) {
 	let bs_reestablish = get_chan_reestablish_msgs!(nodes[1], nodes[0]).pop().unwrap();
 	nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish);
 	let as_err = nodes[0].node.get_and_clear_pending_msg_events();
-	assert_eq!(as_err.len(), 1);
+	assert_eq!(as_err.len(), 2);
 	let bs_commitment_tx;
-	match as_err[0] {
+	match as_err[1] {
  MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
  nodes[1].node.handle_error(&nodes[0].node.get_our_node_id(), msg);

lightning/src/ln/channel.rs

@@ -3992,7 +3992,7 @@ impl<SP: Deref> Channel<SP> where
 
  if msg.next_local_commitment_number >= INITIAL_COMMITMENT_NUMBER || msg.next_remote_commitment_number >= INITIAL_COMMITMENT_NUMBER ||
  msg.next_local_commitment_number == 0 {
- return Err(ChannelError::Close("Peer sent a garbage channel_reestablish (usually an lnd node with lost state asking us to force-close for them)".to_owned()));
+ return Err(ChannelError::Close("Peer sent an invalid channel_reestablish to force close in a non-standard way".to_owned()));
  }
 
  if msg.next_remote_commitment_number > 0 {

lightning/src/ln/channelmanager.rs

@@ -447,16 +447,17 @@ impl MsgHandleErrInternal {
 	}
 	#[inline]
 	fn from_finish_shutdown(err: String, channel_id: ChannelId, user_channel_id: u128, shutdown_res: ShutdownResult, channel_update: Option<msgs::ChannelUpdate>, channel_capacity: u64) -> Self {
+ let err_msg = msgs::ErrorMessage { channel_id, data: err.clone() };
+ let action = if let (Some(_), ..) = &shutdown_res {
+ // We have a closing `ChannelMonitorUpdate`, which means the channel was funded and we
+ // should disconnect our peer such that we force them to broadcast their latest
+ // commitment upon reconnecting.
+ msgs::ErrorAction::DisconnectPeer { msg: Some(err_msg) }
+ } else {
+ msgs::ErrorAction::SendErrorMessage { msg: err_msg }
+ };
  Self {
- err: LightningError {
- err: err.clone(),
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage {
- channel_id,
- data: err
- },
- },
- },
+ err: LightningError { err, action },
  chan_id: Some((channel_id, user_channel_id)),
  shutdown_finish: Some((shutdown_res, channel_update)),
  channel_capacity: Some(channel_capacity)
@@ -2812,8 +2813,8 @@ where
  peer_state.pending_msg_events.push(
  events::MessageSendEvent::HandleError {
  node_id: counterparty_node_id,
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage { channel_id: *channel_id, data: "Channel force-closed".to_owned() }
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage { channel_id: *channel_id, data: "Channel force-closed".to_owned() })
  },
  }
  );
@@ -4296,8 +4297,9 @@ where
  }
  }
  }
- let (counterparty_node_id, forward_chan_id) = match self.short_to_chan_info.read().unwrap().get(&short_chan_id) {
- Some((cp_id, chan_id)) => (cp_id.clone(), chan_id.clone()),
+ let chan_info_opt = self.short_to_chan_info.read().unwrap().get(&short_chan_id).cloned();
+ let (counterparty_node_id, forward_chan_id) = match chan_info_opt {
+ Some((cp_id, chan_id)) => (cp_id, chan_id),
  None => {
  forwarding_channel_not_found!();
  continue;
@@ -6785,7 +6787,10 @@ where
  let peer_state_mutex = per_peer_state.get(counterparty_node_id)
  .ok_or_else(|| {
  debug_assert!(false);
- MsgHandleErrInternal::send_err_msg_no_close(format!("Can't find a peer matching the passed counterparty node_id {}", counterparty_node_id), msg.channel_id)
+ MsgHandleErrInternal::send_err_msg_no_close(
+ format!("Can't find a peer matching the passed counterparty node_id {}", counterparty_node_id),
+ msg.channel_id
+ )
  })?;
  let mut peer_state_lock = peer_state_mutex.lock().unwrap();
  let peer_state = &mut *peer_state_lock;
@@ -6829,7 +6834,39 @@ where
  "Got a channel_reestablish message for an unfunded channel!".into())), chan_phase_entry);
  }
  },
- 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))
+ hash_map::Entry::Vacant(_) => {
+ log_debug!(self.logger, "Sending bogus ChannelReestablish for unknown channel {} to force channel closure",
+ log_bytes!(msg.channel_id.0));
+ // Unfortunately, lnd doesn't force close on errors
+ // (https://github.com/lightningnetwork/lnd/blob/abb1e3463f3a83bbb843d5c399869dbe930ad94f/htlcswitch/link.go#L2119).
+ // One of the few ways to get an lnd counterparty to force close is by
+ // replicating what they do when restoring static channel backups (SCBs). They
+ // send an invalid `ChannelReestablish` with `0` commitment numbers and an
+ // invalid `your_last_per_commitment_secret`.
+ //
+ // Since we received a `ChannelReestablish` for a channel that doesn't exist, we
+ // can assume it's likely the channel closed from our point of view, but it
+ // remains open on the counterparty's side. By sending this bogus
+ // `ChannelReestablish` message now as a response to theirs, we trigger them to
+ // force close broadcasting their latest state. If the closing transaction from
+ // our point of view remains unconfirmed, it'll enter a race with the
+ // counterparty's to-be-broadcast latest commitment transaction.
+ peer_state.pending_msg_events.push(MessageSendEvent::SendChannelReestablish {
+ node_id: *counterparty_node_id,
+ msg: msgs::ChannelReestablish {
+ channel_id: msg.channel_id,
+ next_local_commitment_number: 0,
+ next_remote_commitment_number: 0,
+ your_last_per_commitment_secret: [1u8; 32],
+ my_current_per_commitment_point: PublicKey::from_slice(&[2u8; 33]).unwrap(),
+ next_funding_txid: 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.channel_id)
+ )
+ }
  }
  };
 
@@ -6893,8 +6930,8 @@ where
  self.issue_channel_close_events(&chan.context, ClosureReason::HolderForceClosed);
  pending_msg_events.push(events::MessageSendEvent::HandleError {
  node_id: chan.context.get_counterparty_node_id(),
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage { channel_id: chan.context.channel_id(), data: "Channel force-closed".to_owned() }
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage { channel_id: chan.context.channel_id(), data: "Channel force-closed".to_owned() })
  },
  });
  }
@@ -7678,10 +7715,12 @@ where
  self.issue_channel_close_events(&channel.context, reason);
  pending_msg_events.push(events::MessageSendEvent::HandleError {
  node_id: channel.context.get_counterparty_node_id(),
- action: msgs::ErrorAction::SendErrorMessage { msg: msgs::ErrorMessage {
- channel_id: channel.context.channel_id(),
- data: reason_message,
- } },
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage {
+ channel_id: channel.context.channel_id(),
+ data: reason_message,
+ })
+ },
  });
  return false;
  }
@@ -11219,6 +11258,67 @@ mod tests {
  let payment_preimage = PaymentPreimage([42; 32]);
  assert_eq!(format!("{}", &payment_preimage), "2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a");
 	}
+
+	#[test]
+	fn test_trigger_lnd_force_close() {
+ let chanmon_cfg = create_chanmon_cfgs(2);
+ let node_cfg = create_node_cfgs(2, &chanmon_cfg);
+ let user_config = test_default_channel_config();
+ let node_chanmgr = create_node_chanmgrs(2, &node_cfg, &[Some(user_config), Some(user_config)]);
+ let nodes = create_network(2, &node_cfg, &node_chanmgr);
+
+ // Open a channel, immediately disconnect each other, and broadcast Alice's latest state.
+ let (_, _, chan_id, funding_tx) = create_announced_chan_between_nodes(&nodes, 0, 1);
+ nodes[0].node.peer_disconnected(&nodes[1].node.get_our_node_id());
+ nodes[1].node.peer_disconnected(&nodes[0].node.get_our_node_id());
+ nodes[0].node.force_close_broadcasting_latest_txn(&chan_id, &nodes[1].node.get_our_node_id()).unwrap();
+ check_closed_broadcast(&nodes[0], 1, true);
+ check_added_monitors(&nodes[0], 1);
+ check_closed_event!(nodes[0], 1, ClosureReason::HolderForceClosed, [nodes[1].node.get_our_node_id()], 100000);
+ {
+ let txn = nodes[0].tx_broadcaster.txn_broadcast();
+ assert_eq!(txn.len(), 1);
+ check_spends!(txn[0], funding_tx);
+ }
+
+ // Since they're disconnected, Bob won't receive Alice's `Error` message. Reconnect them
+ // such that Bob sends a `ChannelReestablish` to Alice since the channel is still open from
+ // their side.
+ nodes[0].node.peer_connected(&nodes[1].node.get_our_node_id(), &msgs::Init {
+ features: nodes[1].node.init_features(), networks: None, remote_network_address: None
+ }, true).unwrap();
+ nodes[1].node.peer_connected(&nodes[0].node.get_our_node_id(), &msgs::Init {
+ features: nodes[0].node.init_features(), networks: None, remote_network_address: None
+ }, false).unwrap();
+ assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
+ let channel_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(), &channel_reestablish);
+
+ // Alice should respond with an error since the channel isn't known, but a bogus
+ // `ChannelReestablish` should be sent first, such that we actually trigger Bob to force
+ // close even if it was an lnd node.
+ let msg_events = nodes[0].node.get_and_clear_pending_msg_events();
+ assert_eq!(msg_events.len(), 2);
+ if let MessageSendEvent::SendChannelReestablish { node_id, msg } = &msg_events[0] {
+ assert_eq!(*node_id, nodes[1].node.get_our_node_id());
+ assert_eq!(msg.next_local_commitment_number, 0);
+ assert_eq!(msg.next_remote_commitment_number, 0);
+ nodes[1].node.handle_channel_reestablish(&nodes[0].node.get_our_node_id(), &msg);
+ } else { panic!() };
+ check_closed_broadcast(&nodes[1], 1, true);
+ check_added_monitors(&nodes[1], 1);
+ let expected_close_reason = ClosureReason::ProcessingError {
+ err: "Peer sent an invalid channel_reestablish to force close in a non-standard way".to_string()
+ };
+ check_closed_event!(nodes[1], 1, expected_close_reason, [nodes[0].node.get_our_node_id()], 100000);
+ {
+ let txn = nodes[1].tx_broadcaster.txn_broadcast();
+ assert_eq!(txn.len(), 1);
+ check_spends!(txn[0], funding_tx);
+ }
+	}
 }
 
 #[cfg(ldk_bench)]

lightning/src/ln/functional_test_utils.rs

@@ -665,6 +665,12 @@ pub fn get_err_msg(node: &Node, recipient: &PublicKey) -> msgs::ErrorMessage {
  assert_eq!(node_id, recipient);
  (*msg).clone()
  },
+ MessageSendEvent::HandleError {
+ action: msgs::ErrorAction::DisconnectPeer { ref msg }, ref node_id
+ } => {
+ assert_eq!(node_id, recipient);
+ msg.as_ref().unwrap().clone()
+ },
  _ => panic!("Unexpected event"),
 	}
 }
@@ -1446,10 +1452,15 @@ pub fn check_closed_broadcast(node: &Node, num_channels: usize, with_error_msg:
  assert_eq!(msg.contents.flags & 2, 2);
  None
  },
- MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { ref msg }, node_id: _ } => {
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { msg }, node_id: _ } => {
  assert!(with_error_msg);
  // TODO: Check node_id
- Some(msg.clone())
+ Some(msg)
+ },
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::DisconnectPeer { msg }, node_id: _ } => {
+ assert!(with_error_msg);
+ // TODO: Check node_id
+ Some(msg.unwrap())
  },
  _ => panic!("Unexpected event"),
  }
@@ -2921,6 +2932,13 @@ pub fn handle_announce_close_broadcast_events<'a, 'b, 'c>(nodes: &Vec<Node<'a, '
  nodes[b].node.handle_error(&nodes[a].node.get_our_node_id(), msg);
  }
  },
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
+ assert_eq!(node_id, nodes[b].node.get_our_node_id());
+ assert_eq!(msg.as_ref().unwrap().data, expected_error);
+ if needs_err_handle {
+ nodes[b].node.handle_error(&nodes[a].node.get_our_node_id(), msg.as_ref().unwrap());
+ }
+ },
  _ => panic!("Unexpected event"),
 	}
 
@@ -2938,6 +2956,10 @@ pub fn handle_announce_close_broadcast_events<'a, 'b, 'c>(nodes: &Vec<Node<'a, '
  assert_eq!(node_id, nodes[a].node.get_our_node_id());
  assert_eq!(msg.data, expected_error);
  },
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
+ assert_eq!(node_id, nodes[a].node.get_our_node_id());
+ assert_eq!(msg.as_ref().unwrap().data, expected_error);
+ },
  _ => panic!("Unexpected event"),
  }
 	}

lightning/src/ln/functional_tests.rs

@@ -1338,9 +1338,9 @@ fn test_duplicate_htlc_different_direction_onchain() {
 	for e in events {
  match e {
  MessageSendEvent::BroadcastChannelUpdate { .. } => {},
- MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
- assert_eq!(msg.data, "Channel closed because commitment or closing transaction was confirmed on chain.");
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because commitment or closing transaction was confirmed on chain.");
  },
  MessageSendEvent::UpdateHTLCs { ref node_id, updates: msgs::CommitmentUpdate { ref update_add_htlcs, ref update_fulfill_htlcs, ref update_fail_htlcs, ref update_fail_malformed_htlcs, .. } } => {
  assert!(update_add_htlcs.is_empty());
@@ -2369,7 +2369,7 @@ fn channel_monitor_network_test() {
  _ => panic!("Unexpected event"),
  };
  match events[1] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id } => {
  assert_eq!(node_id, nodes[4].node.get_our_node_id());
  },
  _ => panic!("Unexpected event"),
@@ -2401,7 +2401,7 @@ fn channel_monitor_network_test() {
  _ => panic!("Unexpected event"),
  };
  match events[1] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id } => {
  assert_eq!(node_id, nodes[3].node.get_our_node_id());
  },
  _ => panic!("Unexpected event"),
@@ -2913,7 +2913,7 @@ fn test_htlc_on_chain_success() {
 	let nodes_0_event = remove_first_msg_event_to_node(&nodes[0].node.get_our_node_id(), &mut events);
 
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id: _ } => {},
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id: _ } => {},
  _ => panic!("Unexpected event"),
 	}
 
@@ -3358,7 +3358,7 @@ fn do_test_commitment_revoked_fail_backward_exhaustive(deliver_bs_raa: bool, use
 
 	let nodes_2_event = remove_first_msg_event_to_node(&nodes[2].node.get_our_node_id(), &mut events);
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { msg: msgs::ErrorMessage { channel_id, ref data } }, node_id: _ } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { msg: Some(msgs::ErrorMessage { channel_id, ref data }) }, node_id: _ } => {
  assert_eq!(channel_id, chan_2.2);
  assert_eq!(data.as_str(), "Channel closed because commitment or closing transaction was confirmed on chain.");
  },
@@ -4920,7 +4920,7 @@ fn test_onchain_to_onchain_claim() {
 	let nodes_0_event = remove_first_msg_event_to_node(&nodes[0].node.get_our_node_id(), &mut msg_events);
 
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id: _ } => {},
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id: _ } => {},
  _ => panic!("Unexpected event"),
 	}
 
@@ -7860,9 +7860,9 @@ fn test_channel_conf_timeout() {
 	let close_ev = nodes[1].node.get_and_clear_pending_msg_events();
 	assert_eq!(close_ev.len(), 1);
 	match close_ev[0] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { ref msg }, ref node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { ref msg }, ref node_id } => {
  assert_eq!(*node_id, nodes[0].node.get_our_node_id());
- assert_eq!(msg.data, "Channel closed because funding transaction failed to confirm within 2016 blocks");
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because funding transaction failed to confirm within 2016 blocks");
  },
  _ => panic!("Unexpected event"),
 	}
@@ -9212,8 +9212,8 @@ fn test_invalid_funding_tx() {
 	assert_eq!(events_2.len(), 1);
 	if let MessageSendEvent::HandleError { node_id, action } = &events_2[0] {
  assert_eq!(*node_id, nodes[0].node.get_our_node_id());
- if let msgs::ErrorAction::SendErrorMessage { msg } = action {
- assert_eq!(msg.data, "Channel closed because of an exception: ".to_owned() + expected_err);
+ if let msgs::ErrorAction::DisconnectPeer { msg } = action {
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because of an exception: ".to_owned() + expected_err);
  } else { panic!(); }
 	} else { panic!(); }
 	assert_eq!(nodes[1].node.list_channels().len(), 0);
@@ -10652,7 +10652,7 @@ fn do_test_funding_and_commitment_tx_confirm_same_block(confirm_remote_commitmen
 	let mut msg_events = closing_node.node.get_and_clear_pending_msg_events();
 	assert_eq!(msg_events.len(), 1);
 	match msg_events.pop().unwrap() {
- MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { .. }, .. } => {},
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::DisconnectPeer { .. }, .. } => {},
  _ => panic!("Unexpected event"),
 	}
 	check_added_monitors(closing_node, 1);

lightning/src/ln/payment_tests.rs

@@ -706,8 +706,8 @@ fn do_retry_with_no_persist(confirm_before_reload: bool) {
 	let bs_reestablish = get_chan_reestablish_msgs!(nodes[1], nodes[0]).pop().unwrap();
 	nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish);
 	let as_err = nodes[0].node.get_and_clear_pending_msg_events();
-	assert_eq!(as_err.len(), 1);
-	match as_err[0] {
+	assert_eq!(as_err.len(), 2);
+	match as_err[1] {
  MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
  nodes[1].node.handle_error(&nodes[0].node.get_our_node_id(), msg);
@@ -881,9 +881,9 @@ fn do_test_completed_payment_not_retryable_on_reload(use_dust: bool) {
 	let bs_reestablish = get_chan_reestablish_msgs!(nodes[1], nodes[0]).pop().unwrap();
 	nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish);
 	let as_err = nodes[0].node.get_and_clear_pending_msg_events();
-	assert_eq!(as_err.len(), 1);
+	assert_eq!(as_err.len(), 2);
 	let bs_commitment_tx;
-	match as_err[0] {
+	match as_err[1] {
  MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
  nodes[1].node.handle_error(&nodes[0].node.get_our_node_id(), msg);

lightning/src/ln/channel.rs

@@ -3992,7 +3992,7 @@ impl<SP: Deref> Channel<SP> where
 
  if msg.next_local_commitment_number >= INITIAL_COMMITMENT_NUMBER || msg.next_remote_commitment_number >= INITIAL_COMMITMENT_NUMBER ||
  msg.next_local_commitment_number == 0 {
- return Err(ChannelError::Close("Peer sent a garbage channel_reestablish (usually an lnd node with lost state asking us to force-close for them)".to_owned()));
+ return Err(ChannelError::Close("Peer sent an invalid channel_reestablish to force close in a non-standard way".to_owned()));
  }
 
  if msg.next_remote_commitment_number > 0 {

lightning/src/ln/channelmanager.rs

@@ -447,16 +447,17 @@ impl MsgHandleErrInternal {
 	}
 	#[inline]
 	fn from_finish_shutdown(err: String, channel_id: ChannelId, user_channel_id: u128, shutdown_res: ShutdownResult, channel_update: Option<msgs::ChannelUpdate>, channel_capacity: u64) -> Self {
+ let err_msg = msgs::ErrorMessage { channel_id, data: err.clone() };
+ let action = if let (Some(_), ..) = &shutdown_res {
+ // We have a closing `ChannelMonitorUpdate`, which means the channel was funded and we
+ // should disconnect our peer such that we force them to broadcast their latest
+ // commitment upon reconnecting.
+ msgs::ErrorAction::DisconnectPeer { msg: Some(err_msg) }
+ } else {
+ msgs::ErrorAction::SendErrorMessage { msg: err_msg }
+ };
  Self {
- err: LightningError {
- err: err.clone(),
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage {
- channel_id,
- data: err
- },
- },
- },
+ err: LightningError { err, action },
  chan_id: Some((channel_id, user_channel_id)),
  shutdown_finish: Some((shutdown_res, channel_update)),
  channel_capacity: Some(channel_capacity)
@@ -2812,8 +2813,8 @@ where
  peer_state.pending_msg_events.push(
  events::MessageSendEvent::HandleError {
  node_id: counterparty_node_id,
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage { channel_id: *channel_id, data: "Channel force-closed".to_owned() }
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage { channel_id: *channel_id, data: "Channel force-closed".to_owned() })
  },
  }
  );
@@ -4296,8 +4297,9 @@ where
  }
  }
  }
- let (counterparty_node_id, forward_chan_id) = match self.short_to_chan_info.read().unwrap().get(&short_chan_id) {
- Some((cp_id, chan_id)) => (cp_id.clone(), chan_id.clone()),
+ let chan_info_opt = self.short_to_chan_info.read().unwrap().get(&short_chan_id).cloned();
+ let (counterparty_node_id, forward_chan_id) = match chan_info_opt {
+ Some((cp_id, chan_id)) => (cp_id, chan_id),
  None => {
  forwarding_channel_not_found!();
  continue;
@@ -6785,7 +6787,10 @@ where
  let peer_state_mutex = per_peer_state.get(counterparty_node_id)
  .ok_or_else(|| {
  debug_assert!(false);
- MsgHandleErrInternal::send_err_msg_no_close(format!("Can't find a peer matching the passed counterparty node_id {}", counterparty_node_id), msg.channel_id)
+ MsgHandleErrInternal::send_err_msg_no_close(
+ format!("Can't find a peer matching the passed counterparty node_id {}", counterparty_node_id),
+ msg.channel_id
+ )
  })?;
  let mut peer_state_lock = peer_state_mutex.lock().unwrap();
  let peer_state = &mut *peer_state_lock;
@@ -6829,7 +6834,39 @@ where
  "Got a channel_reestablish message for an unfunded channel!".into())), chan_phase_entry);
  }
  },
- 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))
+ hash_map::Entry::Vacant(_) => {
+ log_debug!(self.logger, "Sending bogus ChannelReestablish for unknown channel {} to force channel closure",
+ log_bytes!(msg.channel_id.0));
+ // Unfortunately, lnd doesn't force close on errors
+ // (https://github.com/lightningnetwork/lnd/blob/abb1e3463f3a83bbb843d5c399869dbe930ad94f/htlcswitch/link.go#L2119).
+ // One of the few ways to get an lnd counterparty to force close is by
+ // replicating what they do when restoring static channel backups (SCBs). They
+ // send an invalid `ChannelReestablish` with `0` commitment numbers and an
+ // invalid `your_last_per_commitment_secret`.
+ //
+ // Since we received a `ChannelReestablish` for a channel that doesn't exist, we
+ // can assume it's likely the channel closed from our point of view, but it
+ // remains open on the counterparty's side. By sending this bogus
+ // `ChannelReestablish` message now as a response to theirs, we trigger them to
+ // force close broadcasting their latest state. If the closing transaction from
+ // our point of view remains unconfirmed, it'll enter a race with the
+ // counterparty's to-be-broadcast latest commitment transaction.
+ peer_state.pending_msg_events.push(MessageSendEvent::SendChannelReestablish {
+ node_id: *counterparty_node_id,
+ msg: msgs::ChannelReestablish {
+ channel_id: msg.channel_id,
+ next_local_commitment_number: 0,
+ next_remote_commitment_number: 0,
+ your_last_per_commitment_secret: [1u8; 32],
+ my_current_per_commitment_point: PublicKey::from_slice(&[2u8; 33]).unwrap(),
+ next_funding_txid: 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.channel_id)
+ )
+ }
  }
  };
 
@@ -6893,8 +6930,8 @@ where
  self.issue_channel_close_events(&chan.context, ClosureReason::HolderForceClosed);
  pending_msg_events.push(events::MessageSendEvent::HandleError {
  node_id: chan.context.get_counterparty_node_id(),
- action: msgs::ErrorAction::SendErrorMessage {
- msg: msgs::ErrorMessage { channel_id: chan.context.channel_id(), data: "Channel force-closed".to_owned() }
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage { channel_id: chan.context.channel_id(), data: "Channel force-closed".to_owned() })
  },
  });
  }
@@ -7678,10 +7715,12 @@ where
  self.issue_channel_close_events(&channel.context, reason);
  pending_msg_events.push(events::MessageSendEvent::HandleError {
  node_id: channel.context.get_counterparty_node_id(),
- action: msgs::ErrorAction::SendErrorMessage { msg: msgs::ErrorMessage {
- channel_id: channel.context.channel_id(),
- data: reason_message,
- } },
+ action: msgs::ErrorAction::DisconnectPeer {
+ msg: Some(msgs::ErrorMessage {
+ channel_id: channel.context.channel_id(),
+ data: reason_message,
+ })
+ },
  });
  return false;
  }
@@ -11219,6 +11258,67 @@ mod tests {
  let payment_preimage = PaymentPreimage([42; 32]);
  assert_eq!(format!("{}", &payment_preimage), "2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a2a");
 	}
+
+	#[test]
+	fn test_trigger_lnd_force_close() {
+ let chanmon_cfg = create_chanmon_cfgs(2);
+ let node_cfg = create_node_cfgs(2, &chanmon_cfg);
+ let user_config = test_default_channel_config();
+ let node_chanmgr = create_node_chanmgrs(2, &node_cfg, &[Some(user_config), Some(user_config)]);
+ let nodes = create_network(2, &node_cfg, &node_chanmgr);
+
+ // Open a channel, immediately disconnect each other, and broadcast Alice's latest state.
+ let (_, _, chan_id, funding_tx) = create_announced_chan_between_nodes(&nodes, 0, 1);
+ nodes[0].node.peer_disconnected(&nodes[1].node.get_our_node_id());
+ nodes[1].node.peer_disconnected(&nodes[0].node.get_our_node_id());
+ nodes[0].node.force_close_broadcasting_latest_txn(&chan_id, &nodes[1].node.get_our_node_id()).unwrap();
+ check_closed_broadcast(&nodes[0], 1, true);
+ check_added_monitors(&nodes[0], 1);
+ check_closed_event!(nodes[0], 1, ClosureReason::HolderForceClosed, [nodes[1].node.get_our_node_id()], 100000);
+ {
+ let txn = nodes[0].tx_broadcaster.txn_broadcast();
+ assert_eq!(txn.len(), 1);
+ check_spends!(txn[0], funding_tx);
+ }
+
+ // Since they're disconnected, Bob won't receive Alice's `Error` message. Reconnect them
+ // such that Bob sends a `ChannelReestablish` to Alice since the channel is still open from
+ // their side.
+ nodes[0].node.peer_connected(&nodes[1].node.get_our_node_id(), &msgs::Init {
+ features: nodes[1].node.init_features(), networks: None, remote_network_address: None
+ }, true).unwrap();
+ nodes[1].node.peer_connected(&nodes[0].node.get_our_node_id(), &msgs::Init {
+ features: nodes[0].node.init_features(), networks: None, remote_network_address: None
+ }, false).unwrap();
+ assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
+ let channel_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(), &channel_reestablish);
+
+ // Alice should respond with an error since the channel isn't known, but a bogus
+ // `ChannelReestablish` should be sent first, such that we actually trigger Bob to force
+ // close even if it was an lnd node.
+ let msg_events = nodes[0].node.get_and_clear_pending_msg_events();
+ assert_eq!(msg_events.len(), 2);
+ if let MessageSendEvent::SendChannelReestablish { node_id, msg } = &msg_events[0] {
+ assert_eq!(*node_id, nodes[1].node.get_our_node_id());
+ assert_eq!(msg.next_local_commitment_number, 0);
+ assert_eq!(msg.next_remote_commitment_number, 0);
+ nodes[1].node.handle_channel_reestablish(&nodes[0].node.get_our_node_id(), &msg);
+ } else { panic!() };
+ check_closed_broadcast(&nodes[1], 1, true);
+ check_added_monitors(&nodes[1], 1);
+ let expected_close_reason = ClosureReason::ProcessingError {
+ err: "Peer sent an invalid channel_reestablish to force close in a non-standard way".to_string()
+ };
+ check_closed_event!(nodes[1], 1, expected_close_reason, [nodes[0].node.get_our_node_id()], 100000);
+ {
+ let txn = nodes[1].tx_broadcaster.txn_broadcast();
+ assert_eq!(txn.len(), 1);
+ check_spends!(txn[0], funding_tx);
+ }
+	}
 }
 
 #[cfg(ldk_bench)]

lightning/src/ln/functional_test_utils.rs

@@ -665,6 +665,12 @@ pub fn get_err_msg(node: &Node, recipient: &PublicKey) -> msgs::ErrorMessage {
  assert_eq!(node_id, recipient);
  (*msg).clone()
  },
+ MessageSendEvent::HandleError {
+ action: msgs::ErrorAction::DisconnectPeer { ref msg }, ref node_id
+ } => {
+ assert_eq!(node_id, recipient);
+ msg.as_ref().unwrap().clone()
+ },
  _ => panic!("Unexpected event"),
 	}
 }
@@ -1446,10 +1452,15 @@ pub fn check_closed_broadcast(node: &Node, num_channels: usize, with_error_msg:
  assert_eq!(msg.contents.flags & 2, 2);
  None
  },
- MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { ref msg }, node_id: _ } => {
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { msg }, node_id: _ } => {
  assert!(with_error_msg);
  // TODO: Check node_id
- Some(msg.clone())
+ Some(msg)
+ },
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::DisconnectPeer { msg }, node_id: _ } => {
+ assert!(with_error_msg);
+ // TODO: Check node_id
+ Some(msg.unwrap())
  },
  _ => panic!("Unexpected event"),
  }
@@ -2921,6 +2932,13 @@ pub fn handle_announce_close_broadcast_events<'a, 'b, 'c>(nodes: &Vec<Node<'a, '
  nodes[b].node.handle_error(&nodes[a].node.get_our_node_id(), msg);
  }
  },
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
+ assert_eq!(node_id, nodes[b].node.get_our_node_id());
+ assert_eq!(msg.as_ref().unwrap().data, expected_error);
+ if needs_err_handle {
+ nodes[b].node.handle_error(&nodes[a].node.get_our_node_id(), msg.as_ref().unwrap());
+ }
+ },
  _ => panic!("Unexpected event"),
 	}
 
@@ -2938,6 +2956,10 @@ pub fn handle_announce_close_broadcast_events<'a, 'b, 'c>(nodes: &Vec<Node<'a, '
  assert_eq!(node_id, nodes[a].node.get_our_node_id());
  assert_eq!(msg.data, expected_error);
  },
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
+ assert_eq!(node_id, nodes[a].node.get_our_node_id());
+ assert_eq!(msg.as_ref().unwrap().data, expected_error);
+ },
  _ => panic!("Unexpected event"),
  }
 	}

lightning/src/ln/functional_tests.rs

@@ -1338,9 +1338,9 @@ fn test_duplicate_htlc_different_direction_onchain() {
 	for e in events {
  match e {
  MessageSendEvent::BroadcastChannelUpdate { .. } => {},
- MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
+ MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::DisconnectPeer { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
- assert_eq!(msg.data, "Channel closed because commitment or closing transaction was confirmed on chain.");
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because commitment or closing transaction was confirmed on chain.");
  },
  MessageSendEvent::UpdateHTLCs { ref node_id, updates: msgs::CommitmentUpdate { ref update_add_htlcs, ref update_fulfill_htlcs, ref update_fail_htlcs, ref update_fail_malformed_htlcs, .. } } => {
  assert!(update_add_htlcs.is_empty());
@@ -2369,7 +2369,7 @@ fn channel_monitor_network_test() {
  _ => panic!("Unexpected event"),
  };
  match events[1] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id } => {
  assert_eq!(node_id, nodes[4].node.get_our_node_id());
  },
  _ => panic!("Unexpected event"),
@@ -2401,7 +2401,7 @@ fn channel_monitor_network_test() {
  _ => panic!("Unexpected event"),
  };
  match events[1] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id } => {
  assert_eq!(node_id, nodes[3].node.get_our_node_id());
  },
  _ => panic!("Unexpected event"),
@@ -2913,7 +2913,7 @@ fn test_htlc_on_chain_success() {
 	let nodes_0_event = remove_first_msg_event_to_node(&nodes[0].node.get_our_node_id(), &mut events);
 
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id: _ } => {},
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id: _ } => {},
  _ => panic!("Unexpected event"),
 	}
 
@@ -3358,7 +3358,7 @@ fn do_test_commitment_revoked_fail_backward_exhaustive(deliver_bs_raa: bool, use
 
 	let nodes_2_event = remove_first_msg_event_to_node(&nodes[2].node.get_our_node_id(), &mut events);
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { msg: msgs::ErrorMessage { channel_id, ref data } }, node_id: _ } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { msg: Some(msgs::ErrorMessage { channel_id, ref data }) }, node_id: _ } => {
  assert_eq!(channel_id, chan_2.2);
  assert_eq!(data.as_str(), "Channel closed because commitment or closing transaction was confirmed on chain.");
  },
@@ -4920,7 +4920,7 @@ fn test_onchain_to_onchain_claim() {
 	let nodes_0_event = remove_first_msg_event_to_node(&nodes[0].node.get_our_node_id(), &mut msg_events);
 
 	match nodes_2_event {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { .. }, node_id: _ } => {},
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { .. }, node_id: _ } => {},
  _ => panic!("Unexpected event"),
 	}
 
@@ -7860,9 +7860,9 @@ fn test_channel_conf_timeout() {
 	let close_ev = nodes[1].node.get_and_clear_pending_msg_events();
 	assert_eq!(close_ev.len(), 1);
 	match close_ev[0] {
- MessageSendEvent::HandleError { action: ErrorAction::SendErrorMessage { ref msg }, ref node_id } => {
+ MessageSendEvent::HandleError { action: ErrorAction::DisconnectPeer { ref msg }, ref node_id } => {
  assert_eq!(*node_id, nodes[0].node.get_our_node_id());
- assert_eq!(msg.data, "Channel closed because funding transaction failed to confirm within 2016 blocks");
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because funding transaction failed to confirm within 2016 blocks");
  },
  _ => panic!("Unexpected event"),
 	}
@@ -9212,8 +9212,8 @@ fn test_invalid_funding_tx() {
 	assert_eq!(events_2.len(), 1);
 	if let MessageSendEvent::HandleError { node_id, action } = &events_2[0] {
  assert_eq!(*node_id, nodes[0].node.get_our_node_id());
- if let msgs::ErrorAction::SendErrorMessage { msg } = action {
- assert_eq!(msg.data, "Channel closed because of an exception: ".to_owned() + expected_err);
+ if let msgs::ErrorAction::DisconnectPeer { msg } = action {
+ assert_eq!(msg.as_ref().unwrap().data, "Channel closed because of an exception: ".to_owned() + expected_err);
  } else { panic!(); }
 	} else { panic!(); }
 	assert_eq!(nodes[1].node.list_channels().len(), 0);
@@ -10652,7 +10652,7 @@ fn do_test_funding_and_commitment_tx_confirm_same_block(confirm_remote_commitmen
 	let mut msg_events = closing_node.node.get_and_clear_pending_msg_events();
 	assert_eq!(msg_events.len(), 1);
 	match msg_events.pop().unwrap() {
- MessageSendEvent::HandleError { action: msgs::ErrorAction::SendErrorMessage { .. }, .. } => {},
+ MessageSendEvent::HandleError { action: msgs::ErrorAction::DisconnectPeer { .. }, .. } => {},
  _ => panic!("Unexpected event"),
 	}
 	check_added_monitors(closing_node, 1);

lightning/src/ln/payment_tests.rs

@@ -706,8 +706,8 @@ fn do_retry_with_no_persist(confirm_before_reload: bool) {
 	let bs_reestablish = get_chan_reestablish_msgs!(nodes[1], nodes[0]).pop().unwrap();
 	nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish);
 	let as_err = nodes[0].node.get_and_clear_pending_msg_events();
-	assert_eq!(as_err.len(), 1);
-	match as_err[0] {
+	assert_eq!(as_err.len(), 2);
+	match as_err[1] {
  MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
  nodes[1].node.handle_error(&nodes[0].node.get_our_node_id(), msg);
@@ -881,9 +881,9 @@ fn do_test_completed_payment_not_retryable_on_reload(use_dust: bool) {
 	let bs_reestablish = get_chan_reestablish_msgs!(nodes[1], nodes[0]).pop().unwrap();
 	nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish);
 	let as_err = nodes[0].node.get_and_clear_pending_msg_events();
-	assert_eq!(as_err.len(), 1);
+	assert_eq!(as_err.len(), 2);
 	let bs_commitment_tx;
-	match as_err[0] {
+	match as_err[1] {
  MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
  assert_eq!(node_id, nodes[1].node.get_our_node_id());
  nodes[1].node.handle_error(&nodes[0].node.get_our_node_id(), msg);