Lean on the holding cell when batch-forwarding/failing HTLCs
[rust-lightning] / lightning / src / ln / channelmanager.rs
index 306739ad6e0d0d7fd9a7e5e2df3c053201f02f7d..fdd0bb202417ba5f62d1a339bb001633db9ade68 100644 (file)
@@ -3170,7 +3170,6 @@ impl<M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelManager<M, T, K, F
                let mut new_events = Vec::new();
                let mut failed_forwards = Vec::new();
                let mut phantom_receives: Vec<(u64, OutPoint, u128, Vec<(PendingHTLCInfo, u64)>)> = Vec::new();
-               let mut handle_errors = Vec::new();
                {
                        let mut forward_htlcs = HashMap::new();
                        mem::swap(&mut forward_htlcs, &mut self.forward_htlcs.lock().unwrap());
@@ -3286,8 +3285,6 @@ impl<M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelManager<M, T, K, F
                                                        continue;
                                                },
                                                hash_map::Entry::Occupied(mut chan) => {
-                                                       let mut add_htlc_msgs = Vec::new();
-                                                       let mut fail_htlc_msgs = Vec::new();
                                                        for forward_info in pending_forwards.drain(..) {
                                                                match forward_info {
                                                                        HTLCForwardInfo::AddHTLC(PendingAddHTLCInfo {
@@ -3306,34 +3303,21 @@ impl<M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelManager<M, T, K, F
                                                                                        // Phantom payments are only PendingHTLCRouting::Receive.
                                                                                        phantom_shared_secret: None,
                                                                                });
-                                                                               match chan.get_mut().send_htlc(outgoing_amt_msat, payment_hash, outgoing_cltv_value, htlc_source.clone(), onion_packet, &self.logger) {
-                                                                                       Err(e) => {
-                                                                                               if let ChannelError::Ignore(msg) = e {
-                                                                                                       log_trace!(self.logger, "Failed to forward HTLC with payment_hash {}: {}", log_bytes!(payment_hash.0), msg);
-                                                                                               } else {
-                                                                                                       panic!("Stated return value requirements in send_htlc() were not met");
-                                                                                               }
-                                                                                               let (failure_code, data) = self.get_htlc_temp_fail_err_and_data(0x1000|7, short_chan_id, chan.get());
-                                                                                               failed_forwards.push((htlc_source, payment_hash,
-                                                                                                       HTLCFailReason::reason(failure_code, data),
-                                                                                                       HTLCDestination::NextHopChannel { node_id: Some(chan.get().get_counterparty_node_id()), channel_id: forward_chan_id }
-                                                                                               ));
-                                                                                               continue;
-                                                                                       },
-                                                                                       Ok(update_add) => {
-                                                                                               match update_add {
-                                                                                                       Some(msg) => { add_htlc_msgs.push(msg); },
-                                                                                                       None => {
-                                                                                                               // Nothing to do here...we're waiting on a remote
-                                                                                                               // revoke_and_ack before we can add anymore HTLCs. The Channel
-                                                                                                               // will automatically handle building the update_add_htlc and
-                                                                                                               // commitment_signed messages when we can.
-                                                                                                               // TODO: Do some kind of timer to set the channel as !is_live()
-                                                                                                               // as we don't really want others relying on us relaying through
-                                                                                                               // this channel currently :/.
-                                                                                                       }
-                                                                                               }
+                                                                               if let Err(e) = chan.get_mut().queue_add_htlc(outgoing_amt_msat,
+                                                                                       payment_hash, outgoing_cltv_value, htlc_source.clone(),
+                                                                                       onion_packet, &self.logger)
+                                                                               {
+                                                                                       if let ChannelError::Ignore(msg) = e {
+                                                                                               log_trace!(self.logger, "Failed to forward HTLC with payment_hash {}: {}", log_bytes!(payment_hash.0), msg);
+                                                                                       } else {
+                                                                                               panic!("Stated return value requirements in send_htlc() were not met");
                                                                                        }
+                                                                                       let (failure_code, data) = self.get_htlc_temp_fail_err_and_data(0x1000|7, short_chan_id, chan.get());
+                                                                                       failed_forwards.push((htlc_source, payment_hash,
+                                                                                               HTLCFailReason::reason(failure_code, data),
+                                                                                               HTLCDestination::NextHopChannel { node_id: Some(chan.get().get_counterparty_node_id()), channel_id: forward_chan_id }
+                                                                                       ));
+                                                                                       continue;
                                                                                }
                                                                        },
                                                                        HTLCForwardInfo::AddHTLC { .. } => {
@@ -3341,77 +3325,22 @@ impl<M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelManager<M, T, K, F
                                                                        },
                                                                        HTLCForwardInfo::FailHTLC { htlc_id, err_packet } => {
                                                                                log_trace!(self.logger, "Failing HTLC back to channel with short id {} (backward HTLC ID {}) after delay", short_chan_id, htlc_id);
-                                                                               match chan.get_mut().get_update_fail_htlc(htlc_id, err_packet, &self.logger) {
-                                                                                       Err(e) => {
-                                                                                               if let ChannelError::Ignore(msg) = e {
-                                                                                                       log_trace!(self.logger, "Failed to fail HTLC with ID {} backwards to short_id {}: {}", htlc_id, short_chan_id, msg);
-                                                                                               } else {
-                                                                                                       panic!("Stated return value requirements in get_update_fail_htlc() were not met");
-                                                                                               }
-                                                                                               // fail-backs are best-effort, we probably already have one
-                                                                                               // pending, and if not that's OK, if not, the channel is on
-                                                                                               // the chain and sending the HTLC-Timeout is their problem.
-                                                                                               continue;
-                                                                                       },
-                                                                                       Ok(Some(msg)) => { fail_htlc_msgs.push(msg); },
-                                                                                       Ok(None) => {
-                                                                                               // Nothing to do here...we're waiting on a remote
-                                                                                               // revoke_and_ack before we can update the commitment
-                                                                                               // transaction. The Channel will automatically handle
-                                                                                               // building the update_fail_htlc and commitment_signed
-                                                                                               // messages when we can.
-                                                                                               // We don't need any kind of timer here as they should fail
-                                                                                               // the channel onto the chain if they can't get our
-                                                                                               // update_fail_htlc in time, it's not our problem.
+                                                                               if let Err(e) = chan.get_mut().queue_fail_htlc(
+                                                                                       htlc_id, err_packet, &self.logger
+                                                                               ) {
+                                                                                       if let ChannelError::Ignore(msg) = e {
+                                                                                               log_trace!(self.logger, "Failed to fail HTLC with ID {} backwards to short_id {}: {}", htlc_id, short_chan_id, msg);
+                                                                                       } else {
+                                                                                               panic!("Stated return value requirements in queue_fail_htlc() were not met");
                                                                                        }
+                                                                                       // fail-backs are best-effort, we probably already have one
+                                                                                       // pending, and if not that's OK, if not, the channel is on
+                                                                                       // the chain and sending the HTLC-Timeout is their problem.
+                                                                                       continue;
                                                                                }
                                                                        },
                                                                }
                                                        }
-
-                                                       if !add_htlc_msgs.is_empty() || !fail_htlc_msgs.is_empty() {
-                                                               let (commitment_msg, monitor_update) = match chan.get_mut().send_commitment(&self.logger) {
-                                                                       Ok(res) => res,
-                                                                       Err(e) => {
-                                                                               // We surely failed send_commitment due to bad keys, in that case
-                                                                               // close channel and then send error message to peer.
-                                                                               let counterparty_node_id = chan.get().get_counterparty_node_id();
-                                                                               let err: Result<(), _>  = match e {
-                                                                                       ChannelError::Ignore(_) | ChannelError::Warn(_) => {
-                                                                                               panic!("Stated return value requirements in send_commitment() were not met");
-                                                                                       }
-                                                                                       ChannelError::Close(msg) => {
-                                                                                               log_trace!(self.logger, "Closing channel {} due to Close-required error: {}", log_bytes!(chan.key()[..]), msg);
-                                                                                               let mut channel = remove_channel!(self, chan);
-                                                                                               // ChannelClosed event is generated by handle_error for us.
-                                                                                               Err(MsgHandleErrInternal::from_finish_shutdown(msg, channel.channel_id(), channel.get_user_id(), channel.force_shutdown(true), self.get_channel_update_for_broadcast(&channel).ok()))
-                                                                                       },
-                                                                               };
-                                                                               handle_errors.push((counterparty_node_id, err));
-                                                                               continue;
-                                                                       }
-                                                               };
-                                                               match self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
-                                                                       ChannelMonitorUpdateStatus::Completed => {},
-                                                                       e => {
-                                                                               handle_errors.push((chan.get().get_counterparty_node_id(), handle_monitor_update_res!(self, e, chan, RAACommitmentOrder::CommitmentFirst, false, true)));
-                                                                               continue;
-                                                                       }
-                                                               }
-                                                               log_debug!(self.logger, "Forwarding HTLCs resulted in a commitment update with {} HTLCs added and {} HTLCs failed for channel {}",
-                                                                       add_htlc_msgs.len(), fail_htlc_msgs.len(), log_bytes!(chan.get().channel_id()));
-                                                               channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
-                                                                       node_id: chan.get().get_counterparty_node_id(),
-                                                                       updates: msgs::CommitmentUpdate {
-                                                                               update_add_htlcs: add_htlc_msgs,
-                                                                               update_fulfill_htlcs: Vec::new(),
-                                                                               update_fail_htlcs: fail_htlc_msgs,
-                                                                               update_fail_malformed_htlcs: Vec::new(),
-                                                                               update_fee: None,
-                                                                               commitment_signed: commitment_msg,
-                                                                       },
-                                                               });
-                                                       }
                                                }
                                        }
                                } else {
@@ -3615,9 +3544,11 @@ impl<M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelManager<M, T, K, F
                }
                self.forward_htlcs(&mut phantom_receives);
 
-               for (counterparty_node_id, err) in handle_errors.drain(..) {
-                       let _ = handle_error!(self, err, counterparty_node_id);
-               }
+               // Freeing the holding cell here is relatively redundant - in practice we'll do it when we
+               // next get a `get_and_clear_pending_msg_events` call, but some tests rely on it, and it's
+               // nice to do the work now if we can rather than while we're trying to get messages in the
+               // network stack.
+               self.check_free_holding_cells();
 
                if new_events.is_empty() { return }
                let mut events = self.pending_events.lock().unwrap();
@@ -5568,11 +5499,6 @@ impl<M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelManager<M, T, K, F
        /// Check the holding cell in each channel and free any pending HTLCs in them if possible.
        /// Returns whether there were any updates such as if pending HTLCs were freed or a monitor
        /// update was applied.
-       ///
-       /// This should only apply to HTLCs which were added to the holding cell because we were
-       /// waiting on a monitor update to finish. In that case, we don't want to free the holding cell
-       /// directly in `channel_monitor_updated` as it may introduce deadlocks calling back into user
-       /// code to inform them of a channel monitor update.
        fn check_free_holding_cells(&self) -> bool {
                let mut has_monitor_update = false;
                let mut failed_htlcs = Vec::new();