Correctly wrap phantom onion errors

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

diff --git a/lightning/src/ln/channelmanager.rs b/lightning/src/ln/channelmanager.rs
index 373b0a199303e09db82ca275f3dbbca914c1515e..1c620bf407834fef3e125a63aed0acd0e075f9e5 100644 (file)
--- a/lightning/src/ln/channelmanager.rs
+++ b/lightning/src/ln/channelmanager.rs
@@ -3075,9 +3075,6 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                                                // the channel is now on chain and our counterparty is
                                                                                // trying to broadcast the HTLC-Timeout, but that's their
                                                                                // problem, not ours.
-                                                                               //
-                                                                               // `fail_htlc_backwards_internal` is never called for
-                                                                               // phantom payments, so this is unreachable for them.
                                                                        }
                                                                }
                                                        }
@@ -3792,12 +3789,18 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                pending_events.push(path_failure);
                                if let Some(ev) = full_failure_ev { pending_events.push(ev); }
                        },
-                       HTLCSource::PreviousHopData(HTLCPreviousHopData { short_channel_id, htlc_id, incoming_packet_shared_secret, .. }) => {
+                       HTLCSource::PreviousHopData(HTLCPreviousHopData { short_channel_id, htlc_id, incoming_packet_shared_secret, phantom_shared_secret, .. }) => {
                                let err_packet = match onion_error {
                                        HTLCFailReason::Reason { failure_code, data } => {
                                                log_trace!(self.logger, "Failing HTLC with payment_hash {} backwards from us with code {}", log_bytes!(payment_hash.0), failure_code);
-                                               let packet = onion_utils::build_failure_packet(&incoming_packet_shared_secret, failure_code, &data[..]).encode();
-                                               onion_utils::encrypt_failure_packet(&incoming_packet_shared_secret, &packet)
+                                               if let Some(phantom_ss) = phantom_shared_secret {
+                                                       let phantom_packet = onion_utils::build_failure_packet(&phantom_ss, failure_code, &data[..]).encode();
+                                                       let encrypted_phantom_packet = onion_utils::encrypt_failure_packet(&phantom_ss, &phantom_packet);
+                                                       onion_utils::encrypt_failure_packet(&incoming_packet_shared_secret, &encrypted_phantom_packet.data[..])
+                                               } else {
+                                                       let packet = onion_utils::build_failure_packet(&incoming_packet_shared_secret, failure_code, &data[..]).encode();
+                                                       onion_utils::encrypt_failure_packet(&incoming_packet_shared_secret, &packet)
+                                               }
                                        },
                                        HTLCFailReason::LightningError { err } => {
                                                log_trace!(self.logger, "Failing HTLC with payment_hash {} backwards with pre-built LightningError", log_bytes!(payment_hash.0));