diff options
Diffstat (limited to 'src/validation.cpp')
-rw-r--r-- | src/validation.cpp | 75 |
1 files changed, 56 insertions, 19 deletions
diff --git a/src/validation.cpp b/src/validation.cpp index 3faa1bf005..2ad3dadeb6 100644 --- a/src/validation.cpp +++ b/src/validation.cpp @@ -78,6 +78,7 @@ uint64_t nPruneTarget = 0; int64_t nMaxTipAge = DEFAULT_MAX_TIP_AGE; bool fEnableReplacement = DEFAULT_ENABLE_REPLACEMENT; +uint256 hashAssumeValid; CFeeRate minRelayTxFee = CFeeRate(DEFAULT_MIN_RELAY_TX_FEE); CAmount maxTxFee = DEFAULT_TRANSACTION_MAXFEE; @@ -1389,11 +1390,10 @@ bool CheckInputs(const CTransaction& tx, CValidationState &state, const CCoinsVi // Only if ALL inputs pass do we perform expensive ECDSA signature checks. // Helps prevent CPU exhaustion attacks. - // Skip ECDSA signature verification when connecting blocks before the - // last block chain checkpoint. Assuming the checkpoints are valid this + // Skip script verification when connecting blocks under the + // assumedvalid block. Assuming the assumedvalid block is valid this // is safe because block merkle hashes are still computed and checked, - // and any change will be caught at the next checkpoint. Of course, if - // the checkpoint is for a chain that's invalid due to false scriptSigs + // 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) { for (unsigned int i = 0; i < tx.vin.size(); i++) { @@ -1721,11 +1721,28 @@ bool ConnectBlock(const CBlock& block, CValidationState& state, CBlockIndex* pin } bool fScriptChecks = true; - if (fCheckpointsEnabled) { - CBlockIndex *pindexLastCheckpoint = Checkpoints::GetLastCheckpoint(chainparams.Checkpoints()); - if (pindexLastCheckpoint && pindexLastCheckpoint->GetAncestor(pindex->nHeight) == pindex) { - // This block is an ancestor of a checkpoint: disable script checks - fScriptChecks = false; + if (!hashAssumeValid.IsNull()) { + // We've been configured with the hash of a block which has been externally verified to have a valid history. + // A suitable default value is included with the software and updated from time to time. Because validity + // relative to a piece of software is an objective fact these defaults can be easily reviewed. + // This setting doesn't force the selection of any particular chain but makes validating some faster by + // effectively caching the result of part of the verification. + BlockMap::const_iterator it = mapBlockIndex.find(hashAssumeValid); + if (it != mapBlockIndex.end()) { + if (it->second->GetAncestor(pindex->nHeight) == pindex && + pindexBestHeader->GetAncestor(pindex->nHeight) == pindex && + pindexBestHeader->nChainWork >= UintToArith256(chainparams.GetConsensus().nMinimumChainWork)) { + // This block is a member of the assumed verified chain and an ancestor of the best header. + // The equivalent time check discourages hashpower from extorting the network via DOS attack + // into accepting an invalid block through telling users they must manually set assumevalid. + // Requiring a software change or burying the invalid block, regardless of the setting, makes + // it hard to hide the implication of the demand. This also avoids having release candidates + // that are hardly doing any signature verification at all in testing without having to + // artificially set the default assumed verified block further back. + // The test against nMinimumChainWork prevents the skipping when denied access to any chain at + // least as good as the expected chain. + fScriptChecks = (GetBlockProofEquivalentTime(*pindexBestHeader, *pindex, *pindexBestHeader, chainparams.GetConsensus()) <= 60 * 60 * 24 * 7 * 2); + } } } @@ -2414,6 +2431,11 @@ static void NotifyHeaderTip() { * that is already loaded (to avoid loading it again from disk). */ bool ActivateBestChain(CValidationState &state, const CChainParams& chainparams, std::shared_ptr<const CBlock> pblock) { + // Note that while we're often called here from ProcessNewBlock, this is + // far from a guarantee. Things in the P2P/RPC will often end up calling + // us in the middle of ProcessNewBlock - do not assume pblock is set + // sanely for performance or correctness! + CBlockIndex *pindexMostWork = NULL; CBlockIndex *pindexNewTip = NULL; do { @@ -2606,6 +2628,7 @@ CBlockIndex* AddToBlockIndex(const CBlockHeader& block) pindexNew->nHeight = pindexNew->pprev->nHeight + 1; pindexNew->BuildSkip(); } + pindexNew->nTimeMax = (pindexNew->pprev ? std::max(pindexNew->pprev->nTimeMax, pindexNew->nTime) : pindexNew->nTime); pindexNew->nChainWork = (pindexNew->pprev ? pindexNew->pprev->nChainWork : 0) + GetBlockProof(*pindexNew); pindexNew->RaiseValidity(BLOCK_VALID_TREE); if (pindexBestHeader == NULL || pindexBestHeader->nChainWork < pindexNew->nChainWork) @@ -3056,14 +3079,18 @@ static bool AcceptBlockHeader(const CBlockHeader& block, CValidationState& state } // Exposed wrapper for AcceptBlockHeader -bool ProcessNewBlockHeaders(const std::vector<CBlockHeader>& headers, CValidationState& state, const CChainParams& chainparams, CBlockIndex** ppindex) +bool ProcessNewBlockHeaders(const std::vector<CBlockHeader>& headers, CValidationState& state, const CChainParams& chainparams, const CBlockIndex** ppindex) { { LOCK(cs_main); for (const CBlockHeader& header : headers) { - if (!AcceptBlockHeader(header, state, chainparams, ppindex)) { + CBlockIndex *pindex = NULL; // Use a temp pindex instead of ppindex to avoid a const_cast + if (!AcceptBlockHeader(header, state, chainparams, &pindex)) { return false; } + if (ppindex) { + *ppindex = pindex; + } } } NotifyHeaderTip(); @@ -3071,8 +3098,10 @@ bool ProcessNewBlockHeaders(const std::vector<CBlockHeader>& headers, CValidatio } /** Store block on disk. If dbp is non-NULL, the file is known to already reside on disk */ -static bool AcceptBlock(const CBlock& block, CValidationState& state, const CChainParams& chainparams, CBlockIndex** ppindex, bool fRequested, const CDiskBlockPos* dbp, bool* fNewBlock) +static bool AcceptBlock(const std::shared_ptr<const CBlock>& pblock, CValidationState& state, const CChainParams& chainparams, CBlockIndex** ppindex, bool fRequested, const CDiskBlockPos* dbp, bool* fNewBlock) { + const CBlock& block = *pblock; + if (fNewBlock) *fNewBlock = false; AssertLockHeld(cs_main); @@ -3118,6 +3147,11 @@ static bool AcceptBlock(const CBlock& block, CValidationState& state, const CCha return error("%s: %s", __func__, FormatStateMessage(state)); } + // Header is valid/has work, merkle tree and segwit merkle tree are good...RELAY NOW + // (but if it does not build on our best tip, let the SendMessages loop relay it) + if (!IsInitialBlockDownload() && chainActive.Tip() == pindex->pprev) + GetMainSignals().NewPoWValidBlock(pindex, pblock); + int nHeight = pindex->nHeight; // Write block to history file @@ -3152,7 +3186,7 @@ bool ProcessNewBlock(const CChainParams& chainparams, const std::shared_ptr<cons CBlockIndex *pindex = NULL; if (fNewBlock) *fNewBlock = false; CValidationState state; - bool ret = AcceptBlock(*pblock, state, chainparams, &pindex, fForceProcessing, NULL, fNewBlock); + bool ret = AcceptBlock(pblock, state, chainparams, &pindex, fForceProcessing, NULL, fNewBlock); CheckBlockIndex(chainparams.GetConsensus()); if (!ret) { GetMainSignals().BlockChecked(*pblock, state); @@ -3416,6 +3450,7 @@ bool static LoadBlockIndexDB(const CChainParams& chainparams) { CBlockIndex* pindex = item.second; pindex->nChainWork = (pindex->pprev ? pindex->pprev->nChainWork : 0) + GetBlockProof(*pindex); + pindex->nTimeMax = (pindex->pprev ? std::max(pindex->pprev->nTimeMax, pindex->nTime) : pindex->nTime); // We can link the chain of blocks for which we've received transactions at some point. // Pruned nodes may have deleted the block. if (pindex->nTx > 0) { @@ -3808,7 +3843,8 @@ bool LoadExternalBlockFile(const CChainParams& chainparams, FILE* fileIn, CDiskB dbp->nPos = nBlockPos; blkdat.SetLimit(nBlockPos + nSize); blkdat.SetPos(nBlockPos); - CBlock block; + std::shared_ptr<CBlock> pblock = std::make_shared<CBlock>(); + CBlock& block = *pblock; blkdat >> block; nRewind = blkdat.GetPos(); @@ -3826,7 +3862,7 @@ bool LoadExternalBlockFile(const CChainParams& chainparams, FILE* fileIn, CDiskB if (mapBlockIndex.count(hash) == 0 || (mapBlockIndex[hash]->nStatus & BLOCK_HAVE_DATA) == 0) { LOCK(cs_main); CValidationState state; - if (AcceptBlock(block, state, chainparams, NULL, true, dbp, NULL)) + if (AcceptBlock(pblock, state, chainparams, NULL, true, dbp, NULL)) nLoaded++; if (state.IsError()) break; @@ -3853,16 +3889,17 @@ bool LoadExternalBlockFile(const CChainParams& chainparams, FILE* fileIn, CDiskB std::pair<std::multimap<uint256, CDiskBlockPos>::iterator, std::multimap<uint256, CDiskBlockPos>::iterator> range = mapBlocksUnknownParent.equal_range(head); while (range.first != range.second) { std::multimap<uint256, CDiskBlockPos>::iterator it = range.first; - if (ReadBlockFromDisk(block, it->second, chainparams.GetConsensus())) + std::shared_ptr<CBlock> pblockrecursive = std::make_shared<CBlock>(); + if (ReadBlockFromDisk(*pblockrecursive, it->second, chainparams.GetConsensus())) { - LogPrint("reindex", "%s: Processing out of order child %s of %s\n", __func__, block.GetHash().ToString(), + LogPrint("reindex", "%s: Processing out of order child %s of %s\n", __func__, pblockrecursive->GetHash().ToString(), head.ToString()); LOCK(cs_main); CValidationState dummy; - if (AcceptBlock(block, dummy, chainparams, NULL, true, &it->second, NULL)) + if (AcceptBlock(pblockrecursive, dummy, chainparams, NULL, true, &it->second, NULL)) { nLoaded++; - queue.push_back(block.GetHash()); + queue.push_back(pblockrecursive->GetHash()); } } range.first++; |