Ensure payments don't ever duplicatively fail/succeed on reload

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

diff --git a/lightning/src/ln/channel.rs b/lightning/src/ln/channel.rs
index 35b658031d51d567ff5d00830ae7220340c2be8d..a9735650e3df841ab959e124b616123316875b1a 100644 (file)
--- a/lightning/src/ln/channel.rs
+++ b/lightning/src/ln/channel.rs
@@ -300,6 +300,7 @@ pub struct CounterpartyForwardingInfo {
 pub(super) struct ForceShutdownResult {
        pub(super) monitor_update: Option<(OutPoint, ChannelMonitorUpdate)>,
        pub(super) outbound_htlcs_failed: Vec<(HTLCSource, PaymentHash)>,
+       pub(super) outbound_onchain_pending_htlcs: Vec<HTLCSource>,
 }
 
 // TODO: We should refactor this to be an Inbound/OutboundChannel until initial setup handshaking
@@ -4305,6 +4306,12 @@ impl<Signer: Sign> Channel<Signer> {
                                _ => {}
                        }
                }
+
+               // We track any HTLCs which were pending outbound via the ChannelMonitor now, but the
+               // ChannelManager still wants the list so that it can de-duplicate any onchain claim events
+               // (especially around restarts).
+               let outbound_onchain_pending_htlcs = self.pending_outbound_htlcs.drain(..).map(|htlc| htlc.source).collect();
+
                let monitor_update = if let Some(funding_txo) = self.get_funding_txo() {
                        // If we haven't yet exchanged funding signatures (ie channel_state < FundingSent),
                        // returning a channel monitor update here would imply a channel monitor update before
@@ -4324,7 +4331,7 @@ impl<Signer: Sign> Channel<Signer> {
 
                self.channel_state = ChannelState::ShutdownComplete as u32;
                self.update_time_counter += 1;
-               ForceShutdownResult { monitor_update, outbound_htlcs_failed: dropped_outbound_htlcs }
+               ForceShutdownResult { monitor_update, outbound_htlcs_failed: dropped_outbound_htlcs, outbound_onchain_pending_htlcs }
        }
 }