Move fail-backwards up for no to-remote output claims

This fixes HTLC fail-backwards in case we haven't yet sent enough
to have a to_remote output to claim, plus some edge cases where it
could be removed due to a fee update, though hopefully that goes
away with simplified_commitment.

diff --git a/src/ln/channelmonitor.rs b/src/ln/channelmonitor.rs
index 13cdfd2fe5d75433c5c28db097af4c12c0965de1..ecb9f3a1816995ae541d5721345d7e7be8a5555f 100644 (file)
--- a/src/ln/channelmonitor.rs
+++ b/src/ln/channelmonitor.rs
@@ -1179,11 +1179,34 @@ impl ChannelMonitor {
                                }
                        }
 
-                       if !inputs.is_empty() || !txn_to_broadcast.is_empty() { // ie we're confident this is actually ours
+                       if !inputs.is_empty() || !txn_to_broadcast.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
                                // We're definitely a remote commitment transaction!
                                log_trace!(self, "Got broadcast of revoked remote commitment transaction, generating general spend tx with {} inputs and {} other txn to broadcast", inputs.len(), txn_to_broadcast.len());
                                watch_outputs.append(&mut tx.output.clone());
                                self.remote_commitment_txn_on_chain.insert(commitment_txid, (commitment_number, tx.output.iter().map(|output| { output.script_pubkey.clone() }).collect()));
+
+                               // TODO: We really should only fail backwards after our revocation claims have been
+                               // confirmed, but we also need to do more other tracking of in-flight pre-confirm
+                               // on-chain claims, so we can do that at the same time.
+                               if let Storage::Local { ref current_remote_commitment_txid, ref prev_remote_commitment_txid, .. } = self.key_storage {
+                                       if let &Some(ref txid) = current_remote_commitment_txid {
+                                               if let Some(&(_, ref latest_outpoints)) = self.remote_claimable_outpoints.get(&txid) {
+                                                       for &(ref payment_hash, ref source, _) in latest_outpoints.iter() {
+                                                               log_trace!(self, "Failing HTLC with payment_hash {} from current remote commitment tx due to broadcast of revoked remote commitment transaction", log_bytes!(payment_hash.0));
+                                                               htlc_updated.push(((*source).clone(), None, payment_hash.clone()));
+                                                       }
+                                               }
+                                       }
+                                       if let &Some(ref txid) = prev_remote_commitment_txid {
+                                               if let Some(&(_, ref prev_outpoint)) = self.remote_claimable_outpoints.get(&txid) {
+                                                       for &(ref payment_hash, ref source, _) in prev_outpoint.iter() {
+                                                               log_trace!(self, "Failing HTLC with payment_hash {} from previous remote commitment tx due to broadcast of revoked remote commitment transaction", log_bytes!(payment_hash.0));
+                                                               htlc_updated.push(((*source).clone(), None, payment_hash.clone()));
+                                                       }
+                                               }
+                                       }
+                               }
+                               // No need to check local commitment txn, symmetric HTLCSource must be present as per-htlc data on remote commitment tx
                        }
                        if inputs.is_empty() { return (txn_to_broadcast, (commitment_txid, watch_outputs), spendable_outputs, htlc_updated); } // Nothing to be done...probably a false positive/local tx
 
@@ -1211,29 +1234,6 @@ impl ChannelMonitor {
                                output: spend_tx.output[0].clone(),
                        });
                        txn_to_broadcast.push(spend_tx);
-
-                       // TODO: We really should only fail backwards after our revocation claims have been
-                       // confirmed, but we also need to do more other tracking of in-flight pre-confirm
-                       // on-chain claims, so we can do that at the same time.
-                       if let Storage::Local { ref current_remote_commitment_txid, ref prev_remote_commitment_txid, .. } = self.key_storage {
-                               if let &Some(ref txid) = current_remote_commitment_txid {
-                                       if let Some(&(_, ref latest_outpoints)) = self.remote_claimable_outpoints.get(&txid) {
-                                               for &(ref payment_hash, ref source, _) in latest_outpoints.iter() {
-                                                       log_trace!(self, "Failing HTLC with payment_hash {} from current remote commitment tx due to broadcast of revoked remote commitment transaction", log_bytes!(payment_hash.0));
-                                                       htlc_updated.push(((*source).clone(), None, payment_hash.clone()));
-                                               }
-                                       }
-                               }
-                               if let &Some(ref txid) = prev_remote_commitment_txid {
-                                       if let Some(&(_, ref prev_outpoint)) = self.remote_claimable_outpoints.get(&txid) {
-                                               for &(ref payment_hash, ref source, _) in prev_outpoint.iter() {
-                                                       log_trace!(self, "Failing HTLC with payment_hash {} from previous remote commitment tx due to broadcast of revoked remote commitment transaction", log_bytes!(payment_hash.0));
-                                                       htlc_updated.push(((*source).clone(), None, payment_hash.clone()));
-                                               }
-                                       }
-                               }
-                       }
-                       // No need to check local commitment txn, symmetric HTLCSource must be present as per-htlc data on remote commitment tx
                } else if let Some(per_commitment_data) = per_commitment_option {
                        // While this isn't useful yet, there is a potential race where if a counterparty
                        // revokes a state at the same time as the commitment transaction for that state is