diff options
Diffstat (limited to 'src/validation.cpp')
-rw-r--r-- | src/validation.cpp | 68 |
1 files changed, 55 insertions, 13 deletions
diff --git a/src/validation.cpp b/src/validation.cpp index 5b746229c9..9a02e9684a 100644 --- a/src/validation.cpp +++ b/src/validation.cpp @@ -14,6 +14,7 @@ #include "consensus/merkle.h" #include "consensus/tx_verify.h" #include "consensus/validation.h" +#include "cuckoocache.h" #include "fs.h" #include "hash.h" #include "init.h" @@ -189,7 +190,7 @@ enum FlushStateMode { static bool FlushStateToDisk(const CChainParams& chainParams, CValidationState &state, FlushStateMode mode, int nManualPruneHeight=0); static void FindFilesToPruneManual(std::set<int>& setFilesToPrune, int nManualPruneHeight); static void FindFilesToPrune(std::set<int>& setFilesToPrune, uint64_t nPruneAfterHeight); -static bool CheckInputs(const CTransaction& tx, CValidationState &state, const CCoinsViewCache &inputs, bool fScriptChecks, unsigned int flags, bool cacheStore, PrecomputedTransactionData& txdata, std::vector<CScriptCheck> *pvChecks = NULL); +static bool CheckInputs(const CTransaction& tx, CValidationState &state, const CCoinsViewCache &inputs, bool fScriptChecks, unsigned int flags, bool cacheSigStore, bool cacheFullScriptStore, PrecomputedTransactionData& txdata, std::vector<CScriptCheck> *pvChecks = nullptr); static FILE* OpenUndoFile(const CDiskBlockPos &pos, bool fReadOnly = false); bool CheckFinalTx(const CTransaction &tx, int flags) @@ -752,29 +753,36 @@ static bool AcceptToMemoryPoolWorker(const CChainParams& chainparams, CTxMemPool // Check against previous transactions // This is done last to help prevent CPU exhaustion denial-of-service attacks. PrecomputedTransactionData txdata(tx); - if (!CheckInputs(tx, state, view, true, scriptVerifyFlags, true, txdata)) { + if (!CheckInputs(tx, state, view, true, scriptVerifyFlags, true, false, 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. CValidationState stateDummy; // Want reported failures to be from first CheckInputs - if (!tx.HasWitness() && CheckInputs(tx, stateDummy, view, true, scriptVerifyFlags & ~(SCRIPT_VERIFY_WITNESS | SCRIPT_VERIFY_CLEANSTACK), true, txdata) && - !CheckInputs(tx, stateDummy, view, true, scriptVerifyFlags & ~SCRIPT_VERIFY_CLEANSTACK, true, txdata)) { + if (!tx.HasWitness() && CheckInputs(tx, stateDummy, view, true, scriptVerifyFlags & ~(SCRIPT_VERIFY_WITNESS | SCRIPT_VERIFY_CLEANSTACK), true, false, txdata) && + !CheckInputs(tx, stateDummy, view, true, scriptVerifyFlags & ~SCRIPT_VERIFY_CLEANSTACK, true, false, txdata)) { // Only the witness is missing, so the transaction itself may be fine. state.SetCorruptionPossible(); } return false; // state filled in by CheckInputs } - // Check again against just the consensus-critical mandatory script - // verification flags, in case of bugs in the standard flags that cause + // Check again against the current block tip's script verification + // flags to cache our script execution flags. This is, of course, + // useless if the next block has different script flags from the + // previous one, but because the cache tracks script flags for us it + // will auto-invalidate and we'll just have a few blocks of extra + // misses on soft-fork activation. + // + // This is also useful in case of bugs in the standard flags that cause // transactions to pass as valid when they're actually invalid. For // instance the STRICTENC flag was incorrectly allowing certain // CHECKSIG NOT scripts to pass, even though they were invalid. // // 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, txdata)) + // invalid blocks (using TestBlockValidity), however allowing such + // transactions into the mempool can be exploited as a DoS attack. + unsigned int currentBlockScriptVerifyFlags = GetBlockScriptFlags(chainActive.Tip(), Params().GetConsensus()); + if (!CheckInputs(tx, state, view, true, currentBlockScriptVerifyFlags, true, true, txdata)) { return error("%s: BUG! PLEASE REPORT THIS! ConnectInputs failed against MANDATORY but not STANDARD flags %s, %s", __func__, hash.ToString(), FormatStateMessage(state)); @@ -1152,12 +1160,25 @@ int GetSpendHeight(const CCoinsViewCache& inputs) return pindexPrev->nHeight + 1; } + +static CuckooCache::cache<uint256, SignatureCacheHasher> scriptExecutionCache; +static uint256 scriptExecutionCacheNonce(GetRandHash()); + +void InitScriptExecutionCache() { + // nMaxCacheSize is unsigned. If -maxsigcachesize is set to zero, + // setup_bytes creates the minimum possible cache (2 elements). + size_t nMaxCacheSize = std::min(std::max((int64_t)0, GetArg("-maxsigcachesize", DEFAULT_MAX_SIG_CACHE_SIZE) / 2), MAX_MAX_SIG_CACHE_SIZE) * ((size_t) 1 << 20); + size_t nElems = scriptExecutionCache.setup_bytes(nMaxCacheSize); + LogPrintf("Using %zu MiB out of %zu requested for script execution cache, able to store %zu elements\n", + (nElems*sizeof(uint256)) >>20, nMaxCacheSize>>20, nElems); +} + /** * Check whether all inputs of this transaction are valid (no double spends, scripts & sigs, amounts) * This does not modify the UTXO set. If pvChecks is not NULL, script checks are pushed onto it * instead of being performed inline. */ -static bool CheckInputs(const CTransaction& tx, CValidationState &state, const CCoinsViewCache &inputs, bool fScriptChecks, unsigned int flags, bool cacheStore, PrecomputedTransactionData& txdata, std::vector<CScriptCheck> *pvChecks) +static bool CheckInputs(const CTransaction& tx, CValidationState &state, const CCoinsViewCache &inputs, bool fScriptChecks, unsigned int flags, bool cacheSigStore, bool cacheFullScriptStore, PrecomputedTransactionData& txdata, std::vector<CScriptCheck> *pvChecks) { if (!tx.IsCoinBase()) { @@ -1177,6 +1198,21 @@ static bool CheckInputs(const CTransaction& tx, CValidationState &state, const C // Of course, if an assumed valid block is invalid due to false scriptSigs // this optimization would allow an invalid chain to be accepted. if (fScriptChecks) { + // First check if script executions have been cached with the same + // flags. Note that this assumes that the inputs provided are + // correct (ie that the transaction hash which is in tx's prevouts + // properly commits to the scriptPubKey in the inputs view of that + // transaction). + uint256 hashCacheEntry; + // We only use the first 19 bytes of nonce to avoid a second SHA + // round - giving us 19 + 32 + 4 = 55 bytes (+ 8 + 1 = 64) + static_assert(55 - sizeof(flags) - 32 >= 128/8, "Want at least 128 bits of nonce for script execution cache"); + CSHA256().Write(scriptExecutionCacheNonce.begin(), 55 - sizeof(flags) - 32).Write(tx.GetWitnessHash().begin(), 32).Write((unsigned char*)&flags, sizeof(flags)).Finalize(hashCacheEntry.begin()); + AssertLockHeld(cs_main); //TODO: Remove this requirement by making CuckooCache not require external locks + if (scriptExecutionCache.contains(hashCacheEntry, !cacheFullScriptStore)) { + return true; + } + for (unsigned int i = 0; i < tx.vin.size(); i++) { const COutPoint &prevout = tx.vin[i].prevout; const Coin& coin = inputs.AccessCoin(prevout); @@ -1191,7 +1227,7 @@ static bool CheckInputs(const CTransaction& tx, CValidationState &state, const C const CAmount amount = coin.out.nValue; // Verify signature - CScriptCheck check(scriptPubKey, amount, tx, i, flags, cacheStore, &txdata); + CScriptCheck check(scriptPubKey, amount, tx, i, flags, cacheSigStore, &txdata); if (pvChecks) { pvChecks->push_back(CScriptCheck()); check.swap(pvChecks->back()); @@ -1204,7 +1240,7 @@ static bool CheckInputs(const CTransaction& tx, CValidationState &state, const C // avoid splitting the network between upgraded and // non-upgraded nodes. CScriptCheck check2(scriptPubKey, amount, tx, i, - flags & ~STANDARD_NOT_MANDATORY_VERIFY_FLAGS, cacheStore, &txdata); + flags & ~STANDARD_NOT_MANDATORY_VERIFY_FLAGS, cacheSigStore, &txdata); if (check2()) return state.Invalid(false, REJECT_NONSTANDARD, strprintf("non-mandatory-script-verify-flag (%s)", ScriptErrorString(check.GetScriptError()))); } @@ -1218,6 +1254,12 @@ static bool CheckInputs(const CTransaction& tx, CValidationState &state, const C return state.DoS(100,false, REJECT_INVALID, strprintf("mandatory-script-verify-flag-failed (%s)", ScriptErrorString(check.GetScriptError()))); } } + + if (cacheFullScriptStore && !pvChecks) { + // We executed all of the provided scripts, and were told to + // cache the result. Do so now. + scriptExecutionCache.insert(hashCacheEntry); + } } } @@ -1684,7 +1726,7 @@ static bool ConnectBlock(const CBlock& block, CValidationState& state, CBlockInd std::vector<CScriptCheck> 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, txdata[i], nScriptCheckThreads ? &vChecks : NULL)) + if (!CheckInputs(tx, state, view, fScriptChecks, flags, fCacheResults, fCacheResults, txdata[i], nScriptCheckThreads ? &vChecks : NULL)) return error("ConnectBlock(): CheckInputs on %s failed with %s", tx.GetHash().ToString(), FormatStateMessage(state)); control.Add(vChecks); |