diff options
Diffstat (limited to 'src/net_processing.cpp')
| -rw-r--r-- | src/net_processing.cpp | 35 |
1 files changed, 33 insertions, 2 deletions
diff --git a/src/net_processing.cpp b/src/net_processing.cpp index ca701a7e5b..ef7f486e0b 100644 --- a/src/net_processing.cpp +++ b/src/net_processing.cpp @@ -187,7 +187,7 @@ namespace { * million to make it highly unlikely for users to have issues with this * filter. * - * We only need to add wtxids to this filter. For non-segwit + * We typically only add wtxids to this filter. For non-segwit * transactions, the txid == wtxid, so this only prevents us from * re-downloading non-segwit transactions when communicating with * non-wtxidrelay peers -- which is important for avoiding malleation @@ -196,6 +196,12 @@ namespace { * the reject filter store wtxids is exactly what we want to avoid * redownload of a rejected transaction. * + * In cases where we can tell that a segwit transaction will fail + * validation no matter the witness, we may add the txid of such + * transaction to the filter as well. This can be helpful when + * communicating with txid-relay peers or if we were to otherwise fetch a + * transaction via txid (eg in our orphan handling). + * * Memory used: 1.3 MB */ std::unique_ptr<CRollingBloomFilter> recentRejects GUARDED_BY(cs_main); @@ -1161,6 +1167,7 @@ static bool MaybePunishNodeForTx(NodeId nodeid, const TxValidationState& state, } // Conflicting (but not necessarily invalid) data or different policy: case TxValidationResult::TX_RECENT_CONSENSUS_CHANGE: + case TxValidationResult::TX_INPUTS_NOT_STANDARD: case TxValidationResult::TX_NOT_STANDARD: case TxValidationResult::TX_MISSING_INPUTS: case TxValidationResult::TX_PREMATURE_SPEND: @@ -2053,6 +2060,19 @@ void static ProcessOrphanTx(CConnman& connman, CTxMemPool& mempool, std::set<uin // if we start doing this too early. assert(recentRejects); recentRejects->insert(orphanTx.GetWitnessHash()); + // If the transaction failed for TX_INPUTS_NOT_STANDARD, + // then we know that the witness was irrelevant to the policy + // failure, since this check depends only on the txid + // (the scriptPubKey being spent is covered by the txid). + // Add the txid to the reject filter to prevent repeated + // processing of this transaction in the event that child + // transactions are later received (resulting in + // parent-fetching by txid via the orphan-handling logic). + if (orphan_state.GetResult() == TxValidationResult::TX_INPUTS_NOT_STANDARD && orphanTx.GetWitnessHash() != orphanTx.GetHash()) { + // We only add the txid if it differs from the wtxid, to + // avoid wasting entries in the rolling bloom filter. + recentRejects->insert(orphanTx.GetHash()); + } } EraseOrphanTx(orphanHash); done = true; @@ -2940,7 +2960,7 @@ void ProcessMessage( // We do the AlreadyHave() check using wtxid, rather than txid - in the // absence of witness malleation, this is strictly better, because the - // recent rejects filter may contain the wtxid but will never contain + // recent rejects filter may contain the wtxid but rarely contains // the txid of a segwit transaction that has been rejected. // In the presence of witness malleation, it's possible that by only // doing the check with wtxid, we could overlook a transaction which @@ -3034,6 +3054,17 @@ void ProcessMessage( // if we start doing this too early. assert(recentRejects); recentRejects->insert(tx.GetWitnessHash()); + // If the transaction failed for TX_INPUTS_NOT_STANDARD, + // then we know that the witness was irrelevant to the policy + // failure, since this check depends only on the txid + // (the scriptPubKey being spent is covered by the txid). + // Add the txid to the reject filter to prevent repeated + // processing of this transaction in the event that child + // transactions are later received (resulting in + // parent-fetching by txid via the orphan-handling logic). + if (state.GetResult() == TxValidationResult::TX_INPUTS_NOT_STANDARD && tx.GetWitnessHash() != tx.GetHash()) { + recentRejects->insert(tx.GetHash()); + } if (RecursiveDynamicUsage(*ptx) < 100000) { AddToCompactExtraTransactions(ptx); } |