diff options
Diffstat (limited to 'src/main.cpp')
| -rw-r--r-- | src/main.cpp | 146 |
1 files changed, 88 insertions, 58 deletions
diff --git a/src/main.cpp b/src/main.cpp index bf7dbe805d..68583361dd 100644 --- a/src/main.cpp +++ b/src/main.cpp @@ -251,31 +251,31 @@ bool CTransaction::IsStandard() const BOOST_FOREACH(const CTxIn& txin, vin) { // Biggest 'standard' txin is a 3-signature 3-of-3 CHECKMULTISIG - // in an OP_EVAL, which is 3 ~80-byte signatures, 3 + // 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) - return error("nonstandard txin, size %d is too large\n", txin.scriptSig.size()); + return false; if (!txin.scriptSig.IsPushOnly()) - return error("nonstandard txin (opcodes other than PUSH): %s", txin.scriptSig.ToString().c_str()); + return false; } BOOST_FOREACH(const CTxOut& txout, vout) if (!::IsStandard(txout.scriptPubKey)) - return error("nonstandard txout: %s", txout.scriptPubKey.ToString().c_str()); + return false; return true; } // // Check transaction inputs, and make sure any -// OP_EVAL transactions are evaluating IsStandard scripts +// pay-to-script-hash transactions are evaluating IsStandard scripts // // Why bother? To avoid denial-of-service attacks; an attacker -// can submit a standard DUP HASH... OP_EVAL transaction, -// which will get accepted into blocks. The script being -// EVAL'ed can be anything; an attacker could use a very +// can submit a standard HASH... OP_EQUAL transaction, +// which will get accepted into blocks. The redemption +// script can be anything; an attacker could use a very // expensive-to-check-upon-redemption script like: // DUP CHECKSIG DROP ... repeated 100 times... OP_1 // -bool CTransaction::AreInputsStandard(std::map<uint256, std::pair<CTxIndex, CTransaction> > mapInputs) const +bool CTransaction::AreInputsStandard(const std::map<uint256, std::pair<CTxIndex, CTransaction> >& mapInputs) const { if (fTestNet) return true; // Allow non-standard on testnet @@ -283,31 +283,51 @@ bool CTransaction::AreInputsStandard(std::map<uint256, std::pair<CTxIndex, CTran for (int i = 0; i < vin.size(); i++) { COutPoint prevout = vin[i].prevout; - assert(mapInputs.count(prevout.hash) > 0); - CTransaction& txPrev = mapInputs[prevout.hash].second; + + std::map<uint256, std::pair<CTxIndex, CTransaction> >::const_iterator mi = mapInputs.find(prevout.hash); + if (mi == mapInputs.end()) + return false; + + const CTransaction& txPrev = (mi->second).second; assert(prevout.n < txPrev.vout.size()); vector<vector<unsigned char> > vSolutions; txnouttype whichType; // get the scriptPubKey corresponding to this input: - CScript& prevScript = txPrev.vout[prevout.n].scriptPubKey; + const CScript& prevScript = txPrev.vout[prevout.n].scriptPubKey; if (!Solver(prevScript, whichType, vSolutions)) - return error("nonstandard txin (spending nonstandard txout %s)", prevScript.ToString().c_str()); + return false; if (whichType == TX_SCRIPTHASH) { vector<vector<unsigned char> > stack; - int nUnused; - if (!EvalScript(stack, vin[i].scriptSig, *this, i, 0, true, nUnused)) + + if (!EvalScript(stack, vin[i].scriptSig, *this, i, 0)) + return false; + if (stack.empty()) return false; CScript subscript(stack.back().begin(), stack.back().end()); if (!::IsStandard(subscript)) - return error("nonstandard txin (nonstandard OP_EVAL subscript %s)", subscript.ToString().c_str()); + return false; } } return true; } +int +CTransaction::GetLegacySigOpCount() const +{ + int nSigOps = 0; + BOOST_FOREACH(const CTxIn& txin, vin) + { + nSigOps += txin.scriptSig.GetSigOpCount(false); + } + BOOST_FOREACH(const CTxOut& txout, vout) + { + nSigOps += txout.scriptPubKey.GetSigOpCount(false); + } + return nSigOps; +} int CMerkleTx::SetMerkleBranch(const CBlock* pblock) @@ -483,7 +503,7 @@ bool CTransaction::AcceptToMemoryPool(CTxDB& txdb, bool fCheckInputs, bool* pfMi return error("AcceptToMemoryPool() : FetchInputs failed %s", hash.ToString().substr(0,10).c_str()); } - // Check for non-standard OP_EVALs in inputs + // Check for non-standard pay-to-script-hash in inputs if (!AreInputsStandard(mapInputs)) return error("AcceptToMemoryPool() : nonstandard transaction input"); @@ -496,6 +516,7 @@ bool CTransaction::AcceptToMemoryPool(CTxDB& txdb, bool fCheckInputs, bool* pfMi *pfMissingInputs = true; return error("AcceptToMemoryPool() : ConnectInputs failed %s", hash.ToString().substr(0,10).c_str()); } + // Checking ECDSA signatures is a CPU bottleneck, so to avoid denial-of-service // attacks disallow transactions with more than one SigOp per 65 bytes. // 65 bytes because that is the minimum size of an ECDSA signature @@ -967,8 +988,8 @@ bool CTransaction::FetchInputs(CTxDB& txdb, const map<uint256, CTxIndex>& mapTes } bool CTransaction::ConnectInputs(map<uint256, pair<CTxIndex, CTransaction> > inputs, - map<uint256, CTxIndex>& mapTestPool, CDiskTxPos posThisTx, - CBlockIndex* pindexBlock, int64& nFees, bool fBlock, bool fMiner, int& nSigOpsRet, int64 nMinFee) + map<uint256, CTxIndex>& mapTestPool, const CDiskTxPos& posThisTx, + const CBlockIndex* pindexBlock, int64& nFees, bool fBlock, bool fMiner, int& nSigOpsRet, int64 nMinFee) { // Take over previous transactions' spent pointers // fBlock is true when this is called from AcceptBlock when a new best-block is added to the blockchain @@ -989,33 +1010,31 @@ bool CTransaction::ConnectInputs(map<uint256, pair<CTxIndex, CTransaction> > inp // If prev is coinbase, check that it's matured if (txPrev.IsCoinBase()) - for (CBlockIndex* pindex = pindexBlock; pindex && pindexBlock->nHeight - pindex->nHeight < COINBASE_MATURITY; pindex = pindex->pprev) + for (const CBlockIndex* pindex = pindexBlock; pindex && pindexBlock->nHeight - pindex->nHeight < COINBASE_MATURITY; pindex = pindex->pprev) if (pindex->nBlockPos == txindex.pos.nBlockPos && pindex->nFile == txindex.pos.nFile) return error("ConnectInputs() : tried to spend coinbase at depth %d", pindexBlock->nHeight - pindex->nHeight); + bool fStrictPayToScriptHash = true; + if (fBlock) + { + // To avoid being on the short end of a block-chain split, + // don't do secondary validation of pay-to-script-hash transactions + // until blocks with timestamps after paytoscripthashtime: + int64 nEvalSwitchTime = GetArg("paytoscripthashtime", 1329264000); // Feb 15, 2012 + fStrictPayToScriptHash = (pindexBlock->nTime >= nEvalSwitchTime); + } + // if !fBlock, then always be strict-- don't accept + // invalid-under-new-rules pay-to-script-hash transactions into + // our memory pool (don't relay them, don't include them + // in blocks we mine). + // Skip ECDSA signature verification when connecting blocks (fBlock=true) // before the last blockchain checkpoint. This is safe because block merkle hashes are // still computed and checked, and any change will be caught at the next checkpoint. if (!(fBlock && (nBestHeight < Checkpoints::GetTotalBlocksEstimate()))) { - bool fStrictOpEval = true; - // This code should be removed when OP_EVAL has - // a majority of hashing power on the network. - if (fBlock) - { - // To avoid being on the short end of a block-chain split, - // interpret OP_EVAL as a NO_OP until blocks with timestamps - // after opevaltime: - int64 nEvalSwitchTime = GetArg("opevaltime", 1328054400); // Feb 1, 2012 - fStrictOpEval = (pindexBlock->nTime >= nEvalSwitchTime); - } - // if !fBlock, then always be strict-- don't accept - // invalid-under-new-rules OP_EVAL transactions into - // our memory pool (don't relay them, don't include them - // in blocks we mine). - // Verify signature - if (!VerifySignature(txPrev, *this, i, nSigOpsRet, fStrictOpEval)) + if (!VerifySignature(txPrev, *this, i, fStrictPayToScriptHash, 0)) return DoS(100,error("ConnectInputs() : %s VerifySignature failed", GetHash().ToString().substr(0,10).c_str())); } @@ -1030,6 +1049,9 @@ bool CTransaction::ConnectInputs(map<uint256, pair<CTxIndex, CTransaction> > inp if (!MoneyRange(txPrev.vout[prevout.n].nValue) || !MoneyRange(nValueIn)) return DoS(100, error("ConnectInputs() : txin values out of range")); + // Calculate sigOps accurately: + nSigOpsRet += txPrev.vout[prevout.n].scriptPubKey.GetSigOpCount(vin[i].scriptSig); + // Mark outpoints as spent txindex.vSpent[prevout.n] = posThisTx; @@ -1090,8 +1112,7 @@ bool CTransaction::ClientConnectInputs() return false; // Verify signature - int nUnused = 0; - if (!VerifySignature(txPrev, *this, i, nUnused, false)) + if (!VerifySignature(txPrev, *this, i, true, 0)) return error("ConnectInputs() : VerifySignature failed"); ///// this is redundant with the mapNextTx stuff, not sure which I want to get rid of @@ -1158,10 +1179,17 @@ bool CBlock::ConnectBlock(CTxDB& txdb, CBlockIndex* pindex) map<uint256, pair<CTxIndex, CTransaction> > mapInputs; if (!tx.FetchInputs(txdb, mapQueuedChanges, true, false, mapInputs)) return false; - if (!tx.ConnectInputs(mapInputs, mapQueuedChanges, posThisTx, pindex, nFees, true, false, nSigOps)) + + int nTxOps = 0; + if (!tx.ConnectInputs(mapInputs, mapQueuedChanges, posThisTx, pindex, nFees, true, false, nTxOps)) return false; + + nSigOps += nTxOps; if (nSigOps > MAX_BLOCK_SIGOPS) return DoS(100, error("ConnectBlock() : too many sigops")); + // There is a different MAX_BLOCK_SIGOPS check in AcceptBlock(); + // a block must satisfy both to make it into the best-chain + // (AcceptBlock() is always called before ConnectBlock()) } // Write queued txindex changes @@ -1441,19 +1469,13 @@ bool CBlock::CheckBlock() const if (!tx.CheckTransaction()) return DoS(tx.nDoS, error("CheckBlock() : CheckTransaction failed")); - // This code should be removed when a compatibility-breaking block chain split has passed. - // Compatibility check for old clients that counted sigops differently: + // Pre-pay-to-script-hash (before version 0.6), this is how sigops + // were counted; there is another check in ConnectBlock when + // transaction inputs are fetched to count pay-to-script-hash sigops: int nSigOps = 0; BOOST_FOREACH(const CTransaction& tx, vtx) { - BOOST_FOREACH(const CTxIn& txin, tx.vin) - { - nSigOps += txin.scriptSig.GetSigOpCount(); - } - BOOST_FOREACH(const CTxOut& txout, tx.vout) - { - nSigOps += txout.scriptPubKey.GetSigOpCount(); - } + nSigOps += tx.GetLegacySigOpCount(); } if (nSigOps > MAX_BLOCK_SIGOPS) return DoS(100, error("CheckBlock() : out-of-bounds SigOpCount")); @@ -2983,7 +3005,8 @@ CBlock* CreateNewBlock(CReserveKey& reservekey) map<uint256, CTxIndex> mapTestPool; uint64 nBlockSize = 1000; uint64 nBlockTx = 0; - int nBlockSigOps = 100; + int nBlockSigOps1 = 100; // pre-0.6 count of sigOps + int nBlockSigOps2 = 100; // post-0.6 count of sigOps while (!mapPriority.empty()) { // Take highest priority transaction off priority queue @@ -2996,6 +3019,11 @@ CBlock* CreateNewBlock(CReserveKey& reservekey) if (nBlockSize + nTxSize >= MAX_BLOCK_SIZE_GEN) continue; + // Legacy limits on sigOps: + int nTxSigOps1 = tx.GetLegacySigOpCount(); + if (nBlockSigOps1 + nTxSigOps1 >= MAX_BLOCK_SIGOPS) + continue; + // Transaction fee required depends on block size bool fAllowFree = (nBlockSize + nTxSize < 4000 || CTransaction::AllowFree(dPriority)); int64 nMinFee = tx.GetMinFee(nBlockSize, fAllowFree, GMF_BLOCK); @@ -3006,18 +3034,20 @@ CBlock* CreateNewBlock(CReserveKey& reservekey) map<uint256, pair<CTxIndex, CTransaction> > mapInputs; if (!tx.FetchInputs(txdb, mapTestPoolTmp, false, true, mapInputs)) continue; - int nTxSigOps = 0; - if (!tx.ConnectInputs(mapInputs, mapTestPoolTmp, CDiskTxPos(1,1,1), pindexPrev, nFees, false, true, nTxSigOps, nMinFee)) + + int nTxSigOps2 = 0; + if (!tx.ConnectInputs(mapInputs, mapTestPoolTmp, CDiskTxPos(1,1,1), pindexPrev, nFees, false, true, nTxSigOps2, nMinFee)) continue; - if (nBlockSigOps + nTxSigOps >= MAX_BLOCK_SIGOPS) + if (nBlockSigOps2 + nTxSigOps2 >= MAX_BLOCK_SIGOPS) continue; swap(mapTestPool, mapTestPoolTmp); // Added pblock->vtx.push_back(tx); nBlockSize += nTxSize; - nBlockSigOps += nTxSigOps; ++nBlockTx; + nBlockSigOps1 += nTxSigOps1; + nBlockSigOps2 += nTxSigOps2; // Add transactions that depend on this one to the priority queue uint256 hash = tx.GetHash(); @@ -3065,10 +3095,10 @@ void IncrementExtraNonce(CBlock* pblock, CBlockIndex* pindexPrev, unsigned int& ++nExtraNonce; pblock->vtx[0].vin[0].scriptSig = CScript() << pblock->nTime << CBigNum(nExtraNonce); - // Put "OP_EVAL" in the coinbase so everybody can tell when + // Put "/P2SH/" in the coinbase so everybody can tell when // a majority of miners support it - const char* pOpEvalName = GetOpName(OP_EVAL); - pblock->vtx[0].vin[0].scriptSig += CScript() << std::vector<unsigned char>(pOpEvalName, pOpEvalName+strlen(pOpEvalName)); + const char* pszP2SH = "/P2SH/"; + pblock->vtx[0].vin[0].scriptSig += CScript() << std::vector<unsigned char>(pszP2SH, pszP2SH+strlen(pszP2SH)); assert(pblock->vtx[0].vin[0].scriptSig.size() <= 100); pblock->hashMerkleRoot = pblock->BuildMerkleTree(); |