Fix spurious panic on bogus funding txn that confirm and are spent

[rust-lightning] / lightning / src / chain / channelmonitor.rs

diff --git a/lightning/src/chain/channelmonitor.rs b/lightning/src/chain/channelmonitor.rs
index 3f7a1055b6dc3f1dba4d21387051cbe0751293e9..48f821d5f0cb712292fee1afda7e94e627c85a36 100644 (file)
--- a/lightning/src/chain/channelmonitor.rs
+++ b/lightning/src/chain/channelmonitor.rs
@@ -1729,6 +1729,26 @@ macro_rules! fail_unbroadcast_htlcs {
        } }
 }
 
+// In the `test_invalid_funding_tx` test, we need a bogus script which matches the HTLC-Accepted
+// witness length match (ie is 136 bytes long). We generate one here which we also use in some
+// in-line tests later.
+
+#[cfg(test)]
+pub fn deliberately_bogus_accepted_htlc_witness_program() -> Vec<u8> {
+       let mut ret = [opcodes::all::OP_NOP.into_u8(); 136];
+       ret[131] = opcodes::all::OP_DROP.into_u8();
+       ret[132] = opcodes::all::OP_DROP.into_u8();
+       ret[133] = opcodes::all::OP_DROP.into_u8();
+       ret[134] = opcodes::all::OP_DROP.into_u8();
+       ret[135] = opcodes::OP_TRUE.into_u8();
+       Vec::from(&ret[..])
+}
+
+#[cfg(test)]
+pub fn deliberately_bogus_accepted_htlc_witness() -> Vec<Vec<u8>> {
+       vec![Vec::new(), Vec::new(), Vec::new(), Vec::new(), deliberately_bogus_accepted_htlc_witness_program().into()].into()
+}
+
 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
@@ -2701,14 +2721,21 @@ impl<Signer: Sign> ChannelMonitorImpl<Signer> {
                                        if *idx == input.previous_output.vout {
                                                #[cfg(test)]
                                                {
-                                                       // If the expected script is a known type, check that the witness
-                                                       // appears to be spending the correct type (ie that the match would
-                                                       // actually succeed in BIP 158/159-style filters).
-                                                       if _script_pubkey.is_v0_p2wsh() {
-                                                               assert_eq!(&bitcoin::Address::p2wsh(&Script::from(input.witness.last().unwrap().to_vec()), bitcoin::Network::Bitcoin).script_pubkey(), _script_pubkey);
-                                                       } else if _script_pubkey.is_v0_p2wpkh() {
-                                                               assert_eq!(&bitcoin::Address::p2wpkh(&bitcoin::PublicKey::from_slice(&input.witness.last().unwrap()).unwrap(), bitcoin::Network::Bitcoin).unwrap().script_pubkey(), _script_pubkey);
-                                                       } else { panic!(); }
+                                                       // If the expected script is a known type, check that the witness
+                                                       // appears to be spending the correct type (ie that the match would
+                                                       // actually succeed in BIP 158/159-style filters).
+                                                       if _script_pubkey.is_v0_p2wsh() {
+                                                               if input.witness.last().unwrap().to_vec() == deliberately_bogus_accepted_htlc_witness_program() {
+                                                                       // In at least one test we use a deliberately bogus witness
+                                                                       // script which hit an old panic. Thus, we check for that here
+                                                                       // and avoid the assert if its the expected bogus script.
+                                                                       return true;
+                                                               }
+
+                                                               assert_eq!(&bitcoin::Address::p2wsh(&Script::from(input.witness.last().unwrap().to_vec()), bitcoin::Network::Bitcoin).script_pubkey(), _script_pubkey);
+                                                       } else if _script_pubkey.is_v0_p2wpkh() {
+                                                               assert_eq!(&bitcoin::Address::p2wpkh(&bitcoin::PublicKey::from_slice(&input.witness.last().unwrap()).unwrap(), bitcoin::Network::Bitcoin).unwrap().script_pubkey(), _script_pubkey);
+                                                       } else { panic!(); }
                                                }
                                                return true;
                                        }
@@ -2793,10 +2820,13 @@ impl<Signer: Sign> ChannelMonitorImpl<Signer> {
                        let prev_last_witness_len = input.witness.second_to_last().map(|w| w.len()).unwrap_or(0);
                        let revocation_sig_claim = (witness_items == 3 && htlctype == Some(HTLCType::OfferedHTLC) && prev_last_witness_len == 33)
                                || (witness_items == 3 && htlctype == Some(HTLCType::AcceptedHTLC) && prev_last_witness_len == 33);
-                       let accepted_preimage_claim = witness_items == 5 && htlctype == Some(HTLCType::AcceptedHTLC);
+                       let accepted_preimage_claim = witness_items == 5 && htlctype == Some(HTLCType::AcceptedHTLC)
+                               && input.witness.second_to_last().unwrap().len() == 32;
                        #[cfg(not(fuzzing))]
                        let accepted_timeout_claim = witness_items == 3 && htlctype == Some(HTLCType::AcceptedHTLC) && !revocation_sig_claim;
-                       let offered_preimage_claim = witness_items == 3 && htlctype == Some(HTLCType::OfferedHTLC) && !revocation_sig_claim;
+                       let offered_preimage_claim = witness_items == 3 && htlctype == Some(HTLCType::OfferedHTLC) &&
+                               !revocation_sig_claim && input.witness.second_to_last().unwrap().len() == 32;
+
                        #[cfg(not(fuzzing))]
                        let offered_timeout_claim = witness_items == 5 && htlctype == Some(HTLCType::OfferedHTLC);