DRY HTLC failure code in check_spend_counterparty_transaction
authorMatt Corallo <git@bluematt.me>
Sat, 31 Jul 2021 03:31:10 +0000 (03:31 +0000)
committerMatt Corallo <git@bluematt.me>
Mon, 9 Aug 2021 16:12:24 +0000 (16:12 +0000)
This extracts the HTLC-not-in-broadcasted-commitment-transaction
code from check_spend_counterparty_transaction and moves it to a
global macro, DRYing up the two very similar codepaths (fixing
some minor logging inconsistencies) in the process.

This macro will be used for local commitment transaction HTLC
failure as well in the next commit.

This commit has no functional change outside of logging.

lightning/src/chain/channelmonitor.rs

index 7904d9bdefa4935a68ab44e04722fe5d5a220dc2..23696e7b8dbdb9cf89d0671e47f8ed854121b1f3 100644 (file)
@@ -1201,6 +1201,69 @@ impl<Signer: Sign> ChannelMonitor<Signer> {
        }
 }
 
+/// Compares a broadcasted commitment transaction's HTLCs with those in the latest state,
+/// failing any HTLCs which didn't make it into the broadcasted commitment transaction back
+/// after ANTI_REORG_DELAY blocks.
+macro_rules! fail_unbroadcast_htlcs {
+       ($self: expr, $commitment_tx_type: expr, $commitment_tx_conf_height: expr, $confirmed_htlcs_list: expr, $logger: expr) => { {
+               macro_rules! check_htlc_fails {
+                       ($txid: expr, $commitment_tx: expr) => {
+                               if let Some(ref latest_outpoints) = $self.counterparty_claimable_outpoints.get($txid) {
+                                       for &(ref htlc, ref source_option) in latest_outpoints.iter() {
+                                               if let &Some(ref source) = source_option {
+                                                       // Check if the HTLC is present in the commitment transaction that was
+                                                       // broadcast, but not if it was below the dust limit, which we should
+                                                       // fail backwards immediately as there is no way for us to learn the
+                                                       // payment_preimage.
+                                                       // Note that if the dust limit were allowed to change between
+                                                       // commitment transactions we'd want to be check whether *any*
+                                                       // broadcastable commitment transaction has the HTLC in it, but it
+                                                       // cannot currently change after channel initialization, so we don't
+                                                       // need to here.
+                                                       let confirmed_htlcs_iter: &mut Iterator<Item = (&HTLCOutputInCommitment, Option<&HTLCSource>)> = &mut $confirmed_htlcs_list;
+                                                       let mut matched_htlc = false;
+                                                       for (ref broadcast_htlc, ref broadcast_source) in confirmed_htlcs_iter {
+                                                               if broadcast_htlc.transaction_output_index.is_some() && Some(&**source) == *broadcast_source {
+                                                                       matched_htlc = true;
+                                                                       break;
+                                                               }
+                                                       }
+                                                       if matched_htlc { continue; }
+                                                       $self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
+                                                               if entry.height != $commitment_tx_conf_height { return true; }
+                                                               match entry.event {
+                                                                       OnchainEvent::HTLCUpdate { source: ref update_source, .. } => {
+                                                                               *update_source != **source
+                                                                       },
+                                                                       _ => true,
+                                                               }
+                                                       });
+                                                       let entry = OnchainEventEntry {
+                                                               txid: *$txid,
+                                                               height: $commitment_tx_conf_height,
+                                                               event: OnchainEvent::HTLCUpdate {
+                                                                       source: (**source).clone(),
+                                                                       payment_hash: htlc.payment_hash.clone(),
+                                                                       onchain_value_satoshis: Some(htlc.amount_msat / 1000),
+                                                               },
+                                                       };
+                                                       log_trace!($logger, "Failing HTLC with payment_hash {} from {} counterparty commitment tx due to broadcast of {} commitment transaction, waiting for confirmation (at height {})",
+                                                               log_bytes!(htlc.payment_hash.0), $commitment_tx, $commitment_tx_type, entry.confirmation_threshold());
+                                                       $self.onchain_events_awaiting_threshold_conf.push(entry);
+                                               }
+                                       }
+                               }
+                       }
+               }
+               if let Some(ref txid) = $self.current_counterparty_commitment_txid {
+                       check_htlc_fails!(txid, "current");
+               }
+               if let Some(ref txid) = $self.prev_counterparty_commitment_txid {
+                       check_htlc_fails!(txid, "previous");
+               }
+       } }
+}
+
 impl<Signer: Sign> ChannelMonitorImpl<Signer> {
        /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
        /// needed by holder commitment transactions HTCLs nor by counterparty ones. Unless we haven't already seen
@@ -1558,43 +1621,7 @@ impl<Signer: Sign> ChannelMonitorImpl<Signer> {
                                }
                                self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
 
-                               macro_rules! check_htlc_fails {
-                                       ($txid: expr, $commitment_tx: expr) => {
-                                               if let Some(ref outpoints) = self.counterparty_claimable_outpoints.get($txid) {
-                                                       for &(ref htlc, ref source_option) in outpoints.iter() {
-                                                               if let &Some(ref source) = source_option {
-                                                                       self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
-                                                                               if entry.height != height { return true; }
-                                                                               match entry.event {
-                                                                                       OnchainEvent::HTLCUpdate { source: ref update_source, .. } => {
-                                                                                               *update_source != **source
-                                                                                       },
-                                                                                       _ => true,
-                                                                               }
-                                                                       });
-                                                                       let entry = OnchainEventEntry {
-                                                                               txid: *$txid,
-                                                                               height,
-                                                                               event: OnchainEvent::HTLCUpdate {
-                                                                                       source: (**source).clone(),
-                                                                                       payment_hash: htlc.payment_hash.clone(),
-                                                                                       onchain_value_satoshis: Some(htlc.amount_msat / 1000),
-                                                                               },
-                                                                       };
-                                                                       log_info!(logger, "Failing HTLC with payment_hash {} from {} counterparty commitment tx due to broadcast of revoked counterparty commitment transaction, waiting for confirmation (at height {})", log_bytes!(htlc.payment_hash.0), $commitment_tx, entry.confirmation_threshold());
-                                                                       self.onchain_events_awaiting_threshold_conf.push(entry);
-                                                               }
-                                                       }
-                                               }
-                                       }
-                               }
-                               if let Some(ref txid) = self.current_counterparty_commitment_txid {
-                                       check_htlc_fails!(txid, "current");
-                               }
-                               if let Some(ref txid) = self.prev_counterparty_commitment_txid {
-                                       check_htlc_fails!(txid, "counterparty");
-                               }
-                               // No need to check holder commitment txn, symmetric HTLCSource must be present as per-htlc data on counterparty commitment tx
+                               fail_unbroadcast_htlcs!(self, "revoked counterparty", height, [].iter().map(|a| *a), logger);
                        }
                } 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
@@ -1610,56 +1637,7 @@ impl<Signer: Sign> ChannelMonitorImpl<Signer> {
                        self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
 
                        log_info!(logger, "Got broadcast of non-revoked counterparty commitment transaction {}", commitment_txid);
-
-                       macro_rules! check_htlc_fails {
-                               ($txid: expr, $commitment_tx: expr, $id: tt) => {
-                                       if let Some(ref latest_outpoints) = self.counterparty_claimable_outpoints.get($txid) {
-                                               $id: for &(ref htlc, ref source_option) in latest_outpoints.iter() {
-                                                       if let &Some(ref source) = source_option {
-                                                               // Check if the HTLC is present in the commitment transaction that was
-                                                               // broadcast, but not if it was below the dust limit, which we should
-                                                               // fail backwards immediately as there is no way for us to learn the
-                                                               // payment_preimage.
-                                                               // Note that if the dust limit were allowed to change between
-                                                               // commitment transactions we'd want to be check whether *any*
-                                                               // broadcastable commitment transaction has the HTLC in it, but it
-                                                               // cannot currently change after channel initialization, so we don't
-                                                               // need to here.
-                                                               for &(ref broadcast_htlc, ref broadcast_source) in per_commitment_data.iter() {
-                                                                       if broadcast_htlc.transaction_output_index.is_some() && Some(source) == broadcast_source.as_ref() {
-                                                                               continue $id;
-                                                                       }
-                                                               }
-                                                               log_trace!(logger, "Failing HTLC with payment_hash {} from {} counterparty commitment tx due to broadcast of counterparty commitment transaction", log_bytes!(htlc.payment_hash.0), $commitment_tx);
-                                                               self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
-                                                                       if entry.height != height { return true; }
-                                                                       match entry.event {
-                                                                               OnchainEvent::HTLCUpdate { source: ref update_source, .. } => {
-                                                                                       *update_source != **source
-                                                                               },
-                                                                               _ => true,
-                                                                       }
-                                                               });
-                                                               self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
-                                                                       txid: *$txid,
-                                                                       height,
-                                                                       event: OnchainEvent::HTLCUpdate {
-                                                                               source: (**source).clone(),
-                                                                               payment_hash: htlc.payment_hash.clone(),
-                                                                               onchain_value_satoshis: Some(htlc.amount_msat / 1000),
-                                                                       },
-                                                               });
-                                                       }
-                                               }
-                                       }
-                               }
-                       }
-                       if let Some(ref txid) = self.current_counterparty_commitment_txid {
-                               check_htlc_fails!(txid, "current", 'current_loop);
-                       }
-                       if let Some(ref txid) = self.prev_counterparty_commitment_txid {
-                               check_htlc_fails!(txid, "previous", 'prev_loop);
-                       }
+                       fail_unbroadcast_htlcs!(self, "counterparty", height, per_commitment_data.iter().map(|(a, b)| (a, b.as_ref().map(|b| b.as_ref()))), logger);
 
                        let htlc_claim_reqs = self.get_counterparty_htlc_output_claim_reqs(commitment_number, commitment_txid, Some(tx));
                        for req in htlc_claim_reqs {