Rebroadcast shutdown on channel_reestablish (and reprocess them)

[rust-lightning] / src / ln / channelmanager.rs

diff --git a/src/ln/channelmanager.rs b/src/ln/channelmanager.rs
index 28444d75ae683a45adc8393d5a4ff2300b057710..5ee2f6725566fcb818eaf306f252ca62c182188a 100644 (file)
--- a/src/ln/channelmanager.rs
+++ b/src/ln/channelmanager.rs
@@ -1929,7 +1929,7 @@ impl ChannelManager {
                //encrypted with the same key. Its not immediately obvious how to usefully exploit that,
                //but we should prevent it anyway.
 
-               let (pending_forward_info, mut channel_state_lock) = self.decode_update_add_htlc_onion(msg);
+               let (mut pending_forward_info, mut channel_state_lock) = self.decode_update_add_htlc_onion(msg);
                let channel_state = channel_state_lock.borrow_parts();
 
                match channel_state.by_id.get_mut(&msg.channel_id) {
@@ -1939,7 +1939,16 @@ impl ChannelManager {
                                        return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
                                }
                                if !chan.is_usable() {
-                                       return Err(MsgHandleErrInternal::from_no_close(HandleError{err: "Channel not yet available for receiving HTLCs", action: Some(msgs::ErrorAction::IgnoreError)}));
+                                       // If the update_add is completely bogus, the call will Err and we will close,
+                                       // but if we've sent a shutdown and they haven't acknowledged it yet, we just
+                                       // want to reject the new HTLC and fail it backwards instead of forwarding.
+                                       if let PendingHTLCStatus::Forward(PendingForwardHTLCInfo { incoming_shared_secret, .. }) = pending_forward_info {
+                                               pending_forward_info = PendingHTLCStatus::Fail(HTLCFailureMsg::Relay(msgs::UpdateFailHTLC {
+                                                       channel_id: msg.channel_id,
+                                                       htlc_id: msg.htlc_id,
+                                                       reason: ChannelManager::build_first_hop_failure_packet(&incoming_shared_secret, 0x1000|20, &self.get_channel_update(chan).unwrap().encode_with_len()[..]),
+                                               }));
+                                       }
                                }
                                chan.update_add_htlc(&msg, pending_forward_info).map_err(|e| MsgHandleErrInternal::from_maybe_close(e))
                        },
@@ -2374,7 +2383,7 @@ impl ChannelManager {
                                if chan.get_their_node_id() != *their_node_id {
                                        return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!", msg.channel_id));
                                }
-                               let (funding_locked, revoke_and_ack, commitment_update, channel_monitor, order) = chan.channel_reestablish(msg)
+                               let (funding_locked, revoke_and_ack, commitment_update, channel_monitor, order, shutdown) = chan.channel_reestablish(msg)
                                        .map_err(|e| MsgHandleErrInternal::from_chan_maybe_close(e, msg.channel_id))?;
                                if let Some(monitor) = channel_monitor {
                                        if let Err(_e) = self.monitor.add_update_monitor(monitor.get_funding_txo().unwrap(), monitor) {
@@ -2413,6 +2422,12 @@ impl ChannelManager {
                                                send_raa!();
                                        },
                                }
+                               if let Some(msg) = shutdown {
+                                       channel_state.pending_msg_events.push(events::MessageSendEvent::SendShutdown {
+                                               node_id: their_node_id.clone(),
+                                               msg,
+                                       });
+                               }
                                Ok(())
                        },
                        None => Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel", msg.channel_id))