From b8c79a057c48c871a5e48bdcdf600fbfe68f656b Mon Sep 17 00:00:00 2001 From: Pieter Wuille Date: Tue, 16 Aug 2016 15:35:45 +0200 Subject: Precompute sighashes Original version by Nicolas Dorier. Precomputing version by Pieter Wuille. --- src/main.cpp | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) (limited to 'src/main.cpp') diff --git a/src/main.cpp b/src/main.cpp index 6e784c508d..5a9691474f 100644 --- a/src/main.cpp +++ b/src/main.cpp @@ -1497,12 +1497,13 @@ bool AcceptToMemoryPoolWorker(CTxMemPool& pool, CValidationState& state, const C // Check against previous transactions // This is done last to help prevent CPU exhaustion denial-of-service attacks. - if (!CheckInputs(tx, state, view, true, scriptVerifyFlags, true)) { + PrecomputedTransactionData txdata(tx); + if (!CheckInputs(tx, state, view, true, scriptVerifyFlags, true, txdata)) { // SCRIPT_VERIFY_CLEANSTACK requires SCRIPT_VERIFY_WITNESS, so we // need to turn both off, and compare against just turning off CLEANSTACK // to see if the failure is specifically due to witness validation. - if (CheckInputs(tx, state, view, true, scriptVerifyFlags & ~(SCRIPT_VERIFY_WITNESS | SCRIPT_VERIFY_CLEANSTACK), true) && - !CheckInputs(tx, state, view, true, scriptVerifyFlags & ~SCRIPT_VERIFY_CLEANSTACK, true)) { + if (CheckInputs(tx, state, view, true, scriptVerifyFlags & ~(SCRIPT_VERIFY_WITNESS | SCRIPT_VERIFY_CLEANSTACK), true, txdata) && + !CheckInputs(tx, state, view, true, scriptVerifyFlags & ~SCRIPT_VERIFY_CLEANSTACK, true, txdata)) { // Only the witness is wrong, so the transaction itself may be fine. state.SetCorruptionPossible(); } @@ -1518,7 +1519,7 @@ bool AcceptToMemoryPoolWorker(CTxMemPool& pool, CValidationState& state, const C // There is a similar check in CreateNewBlock() to prevent creating // invalid blocks, however allowing such transactions into the mempool // can be exploited as a DoS attack. - if (!CheckInputs(tx, state, view, true, MANDATORY_SCRIPT_VERIFY_FLAGS, true)) + if (!CheckInputs(tx, state, view, true, MANDATORY_SCRIPT_VERIFY_FLAGS, true, txdata)) { return error("%s: BUG! PLEASE REPORT THIS! ConnectInputs failed against MANDATORY but not STANDARD flags %s, %s", __func__, hash.ToString(), FormatStateMessage(state)); @@ -1915,7 +1916,7 @@ void UpdateCoins(const CTransaction& tx, CCoinsViewCache& inputs, int nHeight) bool CScriptCheck::operator()() { const CScript &scriptSig = ptxTo->vin[nIn].scriptSig; const CScriptWitness *witness = (nIn < ptxTo->wit.vtxinwit.size()) ? &ptxTo->wit.vtxinwit[nIn].scriptWitness : NULL; - if (!VerifyScript(scriptSig, scriptPubKey, witness, nFlags, CachingTransactionSignatureChecker(ptxTo, nIn, amount, cacheStore), &error)) { + if (!VerifyScript(scriptSig, scriptPubKey, witness, nFlags, CachingTransactionSignatureChecker(ptxTo, nIn, amount, cacheStore, *txdata), &error)) { return false; } return true; @@ -1974,7 +1975,7 @@ bool CheckTxInputs(const CTransaction& tx, CValidationState& state, const CCoins } }// namespace Consensus -bool CheckInputs(const CTransaction& tx, CValidationState &state, const CCoinsViewCache &inputs, bool fScriptChecks, unsigned int flags, bool cacheStore, std::vector *pvChecks) +bool CheckInputs(const CTransaction& tx, CValidationState &state, const CCoinsViewCache &inputs, bool fScriptChecks, unsigned int flags, bool cacheStore, PrecomputedTransactionData& txdata, std::vector *pvChecks) { if (!tx.IsCoinBase()) { @@ -2001,7 +2002,7 @@ bool CheckInputs(const CTransaction& tx, CValidationState &state, const CCoinsVi assert(coins); // Verify signature - CScriptCheck check(*coins, tx, i, flags, cacheStore); + CScriptCheck check(*coins, tx, i, flags, cacheStore, &txdata); if (pvChecks) { pvChecks->push_back(CScriptCheck()); check.swap(pvChecks->back()); @@ -2014,7 +2015,7 @@ bool CheckInputs(const CTransaction& tx, CValidationState &state, const CCoinsVi // avoid splitting the network between upgraded and // non-upgraded nodes. CScriptCheck check2(*coins, tx, i, - flags & ~STANDARD_NOT_MANDATORY_VERIFY_FLAGS, cacheStore); + flags & ~STANDARD_NOT_MANDATORY_VERIFY_FLAGS, cacheStore, &txdata); if (check2()) return state.Invalid(false, REJECT_NONSTANDARD, strprintf("non-mandatory-script-verify-flag (%s)", ScriptErrorString(check.GetScriptError()))); } @@ -2412,6 +2413,8 @@ bool ConnectBlock(const CBlock& block, CValidationState& state, CBlockIndex* pin std::vector > vPos; vPos.reserve(block.vtx.size()); blockundo.vtxundo.reserve(block.vtx.size() - 1); + std::vector txdata; + txdata.reserve(block.vtx.size()); // Required so that pointers to individual PrecomputedTransactionData don't get invalidated for (unsigned int i = 0; i < block.vtx.size(); i++) { const CTransaction &tx = block.vtx[i]; @@ -2458,13 +2461,14 @@ bool ConnectBlock(const CBlock& block, CValidationState& state, CBlockIndex* pin return state.DoS(100, error("ConnectBlock(): too many sigops"), REJECT_INVALID, "bad-blk-sigops"); + txdata.emplace_back(tx); if (!tx.IsCoinBase()) { nFees += view.GetValueIn(tx)-tx.GetValueOut(); std::vector vChecks; bool fCacheResults = fJustCheck; /* Don't cache results if we're actually connecting blocks (still consult the cache, though) */ - if (!CheckInputs(tx, state, view, fScriptChecks, flags, fCacheResults, nScriptCheckThreads ? &vChecks : NULL)) + if (!CheckInputs(tx, state, view, fScriptChecks, flags, fCacheResults, txdata[i], nScriptCheckThreads ? &vChecks : NULL)) return error("ConnectBlock(): CheckInputs on %s failed with %s", tx.GetHash().ToString(), FormatStateMessage(state)); control.Add(vChecks); -- cgit v1.2.3