Merge pull request #319 from TheBlueMatt/2019-03-htlc-sorting

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

diff --git a/src/ln/channel.rs b/src/ln/channel.rs
index 3745c11a1ae295b58ff8e2af23f43a52a9517f38..b67468b3859ecd5e1a50c951ce02d6670f39d05d 100644 (file)
--- a/src/ln/channel.rs
+++ b/src/ln/channel.rs
@@ -935,7 +935,19 @@ impl Channel {
                        }, None));
                }
 
-               transaction_utils::sort_outputs(&mut txouts);
+               transaction_utils::sort_outputs(&mut txouts, |a, b| {
+                       if let &Some(ref a_htlc) = a {
+                               if let &Some(ref b_htlc) = b {
+                                       a_htlc.0.cltv_expiry.cmp(&b_htlc.0.cltv_expiry)
+                                               // Note that due to hash collisions, we have to have a fallback comparison
+                                               // here for fuzztarget mode (otherwise at least chanmon_fail_consistency
+                                               // may fail)!
+                                               .then(a_htlc.0.payment_hash.0.cmp(&b_htlc.0.payment_hash.0))
+                               // For non-HTLC outputs, if they're copying our SPK we don't really care if we
+                               // close the channel due to mismatches - they're doing something dumb:
+                               } else { cmp::Ordering::Equal }
+                       } else { cmp::Ordering::Equal }
+               });
 
                let mut outputs: Vec<TxOut> = Vec::with_capacity(txouts.len());
                let mut htlcs_included: Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)> = Vec::with_capacity(txouts.len() + included_dust_htlcs.len());
@@ -1011,7 +1023,7 @@ impl Channel {
                        }, ()));
                }
 
-               transaction_utils::sort_outputs(&mut txouts);
+               transaction_utils::sort_outputs(&mut txouts, |_, _| { cmp::Ordering::Equal }); // Ordering doesnt matter if they used our pubkey...
 
                let mut outputs: Vec<TxOut> = Vec::new();
                for out in txouts.drain(..) {