diff options
Diffstat (limited to 'src/main.cpp')
| -rw-r--r-- | src/main.cpp | 38 |
1 files changed, 27 insertions, 11 deletions
diff --git a/src/main.cpp b/src/main.cpp index 83a640d7f3..a0f4f40cb1 100644 --- a/src/main.cpp +++ b/src/main.cpp @@ -515,10 +515,14 @@ bool IsStandardTx(const CTransaction& tx, string& reason) BOOST_FOREACH(const CTxIn& txin, tx.vin) { - // Biggest 'standard' txin is a 3-signature 3-of-3 CHECKMULTISIG - // pay-to-script-hash, which is 3 ~80-byte signatures, 3 - // ~65-byte public keys, plus a few script ops. - if (txin.scriptSig.size() > 500) { + // Biggest 'standard' txin is a 15-of-15 P2SH multisig with compressed + // keys. (remember the 520 byte limit on redeemScript size) That works + // out to a (15*(33+1))+3=513 byte redeemScript, 513+1+15*(73+1)=1624 + // bytes of scriptSig, which we round off to 1650 bytes for some minor + // future-proofing. That's also enough to spend a 20-of-20 + // CHECKMULTISIG scriptPubKey, though such a scriptPubKey is not + // considered standard) + if (txin.scriptSig.size() > 1650) { reason = "scriptsig-size"; return false; } @@ -945,7 +949,7 @@ bool AcceptToMemoryPool(CTxMemPool& pool, CValidationState &state, const CTransa // Check against previous transactions // This is done last to help prevent CPU exhaustion denial-of-service attacks. - if (!CheckInputs(tx, state, view, true, SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_STRICTENC)) + if (!CheckInputs(tx, state, view, true, STANDARD_SCRIPT_VERIFY_FLAGS)) { return error("AcceptToMemoryPool: : ConnectInputs failed %s", hash.ToString()); } @@ -1588,14 +1592,26 @@ bool CheckInputs(const CTransaction& tx, CValidationState &state, CCoinsViewCach pvChecks->push_back(CScriptCheck()); check.swap(pvChecks->back()); } else if (!check()) { - if (flags & SCRIPT_VERIFY_STRICTENC) { - // For now, check whether the failure was caused by non-canonical - // encodings or not; if so, don't trigger DoS protection. - CScriptCheck check(coins, tx, i, flags & (~SCRIPT_VERIFY_STRICTENC), 0); + if (flags & STANDARD_NOT_MANDATORY_VERIFY_FLAGS) { + // Check whether the failure was caused by a + // non-mandatory script verification check, such as + // non-standard DER encodings or non-null dummy + // arguments; if so, don't trigger DoS protection to + // avoid splitting the network between upgraded and + // non-upgraded nodes. + CScriptCheck check(coins, tx, i, + flags & ~STANDARD_NOT_MANDATORY_VERIFY_FLAGS, 0); if (check()) - return state.Invalid(false, REJECT_NONSTANDARD, "non-canonical"); + return state.Invalid(false, REJECT_NONSTANDARD, "non-mandatory-script-verify-flag"); } - return state.DoS(100,false, REJECT_NONSTANDARD, "non-canonical"); + // Failures of other flags indicate a transaction that is + // invalid in new blocks, e.g. a invalid P2SH. We DoS ban + // such nodes as they are not following the protocol. That + // said during an upgrade careful thought should be taken + // as to the correct behavior - we may want to continue + // peering with non-upgraded nodes even after a soft-fork + // super-majority vote has passed. + return state.DoS(100,false, REJECT_INVALID, "mandatory-script-verify-flag-failed"); } } } |