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Diffstat (limited to 'src/validation.cpp')
| -rw-r--r-- | src/validation.cpp | 4849 |
1 files changed, 4849 insertions, 0 deletions
diff --git a/src/validation.cpp b/src/validation.cpp new file mode 100644 index 0000000000..fceb135854 --- /dev/null +++ b/src/validation.cpp @@ -0,0 +1,4849 @@ +// Copyright (c) 2009-2010 Satoshi Nakamoto +// Copyright (c) 2009-2018 The Bitcoin Core developers +// Distributed under the MIT software license, see the accompanying +// file COPYING or http://www.opensource.org/licenses/mit-license.php. + +#include <validation.h> + +#include <arith_uint256.h> +#include <chain.h> +#include <chainparams.h> +#include <checkpoints.h> +#include <checkqueue.h> +#include <consensus/consensus.h> +#include <consensus/merkle.h> +#include <consensus/tx_verify.h> +#include <consensus/validation.h> +#include <cuckoocache.h> +#include <hash.h> +#include <index/txindex.h> +#include <policy/fees.h> +#include <policy/policy.h> +#include <policy/rbf.h> +#include <pow.h> +#include <primitives/block.h> +#include <primitives/transaction.h> +#include <random.h> +#include <reverse_iterator.h> +#include <script/script.h> +#include <script/sigcache.h> +#include <script/standard.h> +#include <shutdown.h> +#include <timedata.h> +#include <tinyformat.h> +#include <txdb.h> +#include <txmempool.h> +#include <ui_interface.h> +#include <undo.h> +#include <util.h> +#include <utilmoneystr.h> +#include <utilstrencodings.h> +#include <validationinterface.h> +#include <warnings.h> + +#include <future> +#include <sstream> + +#include <boost/algorithm/string/replace.hpp> +#include <boost/thread.hpp> + +#if defined(NDEBUG) +# error "Bitcoin cannot be compiled without assertions." +#endif + +#define MICRO 0.000001 +#define MILLI 0.001 + +/** + * Global state + */ +namespace { + struct CBlockIndexWorkComparator + { + bool operator()(const CBlockIndex *pa, const CBlockIndex *pb) const { + // First sort by most total work, ... + if (pa->nChainWork > pb->nChainWork) return false; + if (pa->nChainWork < pb->nChainWork) return true; + + // ... then by earliest time received, ... + if (pa->nSequenceId < pb->nSequenceId) return false; + if (pa->nSequenceId > pb->nSequenceId) return true; + + // Use pointer address as tie breaker (should only happen with blocks + // loaded from disk, as those all have id 0). + if (pa < pb) return false; + if (pa > pb) return true; + + // Identical blocks. + return false; + } + }; +} // anon namespace + +enum DisconnectResult +{ + DISCONNECT_OK, // All good. + DISCONNECT_UNCLEAN, // Rolled back, but UTXO set was inconsistent with block. + DISCONNECT_FAILED // Something else went wrong. +}; + +class ConnectTrace; + +/** + * CChainState stores and provides an API to update our local knowledge of the + * current best chain and header tree. + * + * It generally provides access to the current block tree, as well as functions + * to provide new data, which it will appropriately validate and incorporate in + * its state as necessary. + * + * Eventually, the API here is targeted at being exposed externally as a + * consumable libconsensus library, so any functions added must only call + * other class member functions, pure functions in other parts of the consensus + * library, callbacks via the validation interface, or read/write-to-disk + * functions (eventually this will also be via callbacks). + */ +class CChainState { +private: + /** + * The set of all CBlockIndex entries with BLOCK_VALID_TRANSACTIONS (for itself and all ancestors) and + * as good as our current tip or better. Entries may be failed, though, and pruning nodes may be + * missing the data for the block. + */ + std::set<CBlockIndex*, CBlockIndexWorkComparator> setBlockIndexCandidates; + + /** + * Every received block is assigned a unique and increasing identifier, so we + * know which one to give priority in case of a fork. + */ + CCriticalSection cs_nBlockSequenceId; + /** Blocks loaded from disk are assigned id 0, so start the counter at 1. */ + int32_t nBlockSequenceId = 1; + /** Decreasing counter (used by subsequent preciousblock calls). */ + int32_t nBlockReverseSequenceId = -1; + /** chainwork for the last block that preciousblock has been applied to. */ + arith_uint256 nLastPreciousChainwork = 0; + + /** In order to efficiently track invalidity of headers, we keep the set of + * blocks which we tried to connect and found to be invalid here (ie which + * were set to BLOCK_FAILED_VALID since the last restart). We can then + * walk this set and check if a new header is a descendant of something in + * this set, preventing us from having to walk mapBlockIndex when we try + * to connect a bad block and fail. + * + * While this is more complicated than marking everything which descends + * from an invalid block as invalid at the time we discover it to be + * invalid, doing so would require walking all of mapBlockIndex to find all + * descendants. Since this case should be very rare, keeping track of all + * BLOCK_FAILED_VALID blocks in a set should be just fine and work just as + * well. + * + * Because we already walk mapBlockIndex in height-order at startup, we go + * ahead and mark descendants of invalid blocks as FAILED_CHILD at that time, + * instead of putting things in this set. + */ + std::set<CBlockIndex*> m_failed_blocks; + + /** + * the ChainState CriticalSection + * A lock that must be held when modifying this ChainState - held in ActivateBestChain() + */ + CCriticalSection m_cs_chainstate; + +public: + CChain chainActive; + BlockMap mapBlockIndex; + std::multimap<CBlockIndex*, CBlockIndex*> mapBlocksUnlinked; + CBlockIndex *pindexBestInvalid = nullptr; + + bool LoadBlockIndex(const Consensus::Params& consensus_params, CBlockTreeDB& blocktree) EXCLUSIVE_LOCKS_REQUIRED(cs_main); + + bool ActivateBestChain(CValidationState &state, const CChainParams& chainparams, std::shared_ptr<const CBlock> pblock); + + /** + * If a block header hasn't already been seen, call CheckBlockHeader on it, ensure + * that it doesn't descend from an invalid block, and then add it to mapBlockIndex. + */ + bool AcceptBlockHeader(const CBlockHeader& block, CValidationState& state, const CChainParams& chainparams, CBlockIndex** ppindex) EXCLUSIVE_LOCKS_REQUIRED(cs_main); + bool AcceptBlock(const std::shared_ptr<const CBlock>& pblock, CValidationState& state, const CChainParams& chainparams, CBlockIndex** ppindex, bool fRequested, const CDiskBlockPos* dbp, bool* fNewBlock) EXCLUSIVE_LOCKS_REQUIRED(cs_main); + + // Block (dis)connection on a given view: + DisconnectResult DisconnectBlock(const CBlock& block, const CBlockIndex* pindex, CCoinsViewCache& view); + bool ConnectBlock(const CBlock& block, CValidationState& state, CBlockIndex* pindex, + CCoinsViewCache& view, const CChainParams& chainparams, bool fJustCheck = false); + + // Block disconnection on our pcoinsTip: + bool DisconnectTip(CValidationState& state, const CChainParams& chainparams, DisconnectedBlockTransactions *disconnectpool); + + // Manual block validity manipulation: + bool PreciousBlock(CValidationState& state, const CChainParams& params, CBlockIndex* pindex) LOCKS_EXCLUDED(cs_main); + bool InvalidateBlock(CValidationState& state, const CChainParams& chainparams, CBlockIndex* pindex) EXCLUSIVE_LOCKS_REQUIRED(cs_main); + void ResetBlockFailureFlags(CBlockIndex* pindex) EXCLUSIVE_LOCKS_REQUIRED(cs_main); + + bool ReplayBlocks(const CChainParams& params, CCoinsView* view); + bool RewindBlockIndex(const CChainParams& params); + bool LoadGenesisBlock(const CChainParams& chainparams); + + void PruneBlockIndexCandidates(); + + void UnloadBlockIndex(); + +private: + bool ActivateBestChainStep(CValidationState& state, const CChainParams& chainparams, CBlockIndex* pindexMostWork, const std::shared_ptr<const CBlock>& pblock, bool& fInvalidFound, ConnectTrace& connectTrace); + bool ConnectTip(CValidationState& state, const CChainParams& chainparams, CBlockIndex* pindexNew, const std::shared_ptr<const CBlock>& pblock, ConnectTrace& connectTrace, DisconnectedBlockTransactions &disconnectpool); + + CBlockIndex* AddToBlockIndex(const CBlockHeader& block) EXCLUSIVE_LOCKS_REQUIRED(cs_main); + /** Create a new block index entry for a given block hash */ + CBlockIndex* InsertBlockIndex(const uint256& hash) EXCLUSIVE_LOCKS_REQUIRED(cs_main); + /** + * Make various assertions about the state of the block index. + * + * By default this only executes fully when using the Regtest chain; see: fCheckBlockIndex. + */ + void CheckBlockIndex(const Consensus::Params& consensusParams); + + void InvalidBlockFound(CBlockIndex *pindex, const CValidationState &state); + CBlockIndex* FindMostWorkChain() EXCLUSIVE_LOCKS_REQUIRED(cs_main); + void ReceivedBlockTransactions(const CBlock& block, CBlockIndex* pindexNew, const CDiskBlockPos& pos, const Consensus::Params& consensusParams) EXCLUSIVE_LOCKS_REQUIRED(cs_main); + + + bool RollforwardBlock(const CBlockIndex* pindex, CCoinsViewCache& inputs, const CChainParams& params) EXCLUSIVE_LOCKS_REQUIRED(cs_main); +} g_chainstate; + + + +CCriticalSection cs_main; + +BlockMap& mapBlockIndex = g_chainstate.mapBlockIndex; +CChain& chainActive = g_chainstate.chainActive; +CBlockIndex *pindexBestHeader = nullptr; +CWaitableCriticalSection g_best_block_mutex; +CConditionVariable g_best_block_cv; +uint256 g_best_block; +int nScriptCheckThreads = 0; +std::atomic_bool fImporting(false); +std::atomic_bool fReindex(false); +bool fHavePruned = false; +bool fPruneMode = false; +bool fIsBareMultisigStd = DEFAULT_PERMIT_BAREMULTISIG; +bool fRequireStandard = true; +bool fCheckBlockIndex = false; +bool fCheckpointsEnabled = DEFAULT_CHECKPOINTS_ENABLED; +size_t nCoinCacheUsage = 5000 * 300; +uint64_t nPruneTarget = 0; +int64_t nMaxTipAge = DEFAULT_MAX_TIP_AGE; +bool fEnableReplacement = DEFAULT_ENABLE_REPLACEMENT; + +uint256 hashAssumeValid; +arith_uint256 nMinimumChainWork; + +CFeeRate minRelayTxFee = CFeeRate(DEFAULT_MIN_RELAY_TX_FEE); +CAmount maxTxFee = DEFAULT_TRANSACTION_MAXFEE; + +CBlockPolicyEstimator feeEstimator; +CTxMemPool mempool(&feeEstimator); +std::atomic_bool g_is_mempool_loaded{false}; + +/** Constant stuff for coinbase transactions we create: */ +CScript COINBASE_FLAGS; + +const std::string strMessageMagic = "Bitcoin Signed Message:\n"; + +// Internal stuff +namespace { + CBlockIndex *&pindexBestInvalid = g_chainstate.pindexBestInvalid; + + /** All pairs A->B, where A (or one of its ancestors) misses transactions, but B has transactions. + * Pruned nodes may have entries where B is missing data. + */ + std::multimap<CBlockIndex*, CBlockIndex*>& mapBlocksUnlinked = g_chainstate.mapBlocksUnlinked; + + CCriticalSection cs_LastBlockFile; + std::vector<CBlockFileInfo> vinfoBlockFile; + int nLastBlockFile = 0; + /** Global flag to indicate we should check to see if there are + * block/undo files that should be deleted. Set on startup + * or if we allocate more file space when we're in prune mode + */ + bool fCheckForPruning = false; + + /** Dirty block index entries. */ + std::set<CBlockIndex*> setDirtyBlockIndex; + + /** Dirty block file entries. */ + std::set<int> setDirtyFileInfo; +} // anon namespace + +CBlockIndex* FindForkInGlobalIndex(const CChain& chain, const CBlockLocator& locator) +{ + AssertLockHeld(cs_main); + + // Find the latest block common to locator and chain - we expect that + // locator.vHave is sorted descending by height. + for (const uint256& hash : locator.vHave) { + CBlockIndex* pindex = LookupBlockIndex(hash); + if (pindex) { + if (chain.Contains(pindex)) + return pindex; + if (pindex->GetAncestor(chain.Height()) == chain.Tip()) { + return chain.Tip(); + } + } + } + return chain.Genesis(); +} + +std::unique_ptr<CCoinsViewDB> pcoinsdbview; +std::unique_ptr<CCoinsViewCache> pcoinsTip; +std::unique_ptr<CBlockTreeDB> pblocktree; + +enum class FlushStateMode { + NONE, + IF_NEEDED, + PERIODIC, + ALWAYS +}; + +// See definition for documentation +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); +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) +{ + AssertLockHeld(cs_main); + + // By convention a negative value for flags indicates that the + // current network-enforced consensus rules should be used. In + // a future soft-fork scenario that would mean checking which + // rules would be enforced for the next block and setting the + // appropriate flags. At the present time no soft-forks are + // scheduled, so no flags are set. + flags = std::max(flags, 0); + + // CheckFinalTx() uses chainActive.Height()+1 to evaluate + // nLockTime because when IsFinalTx() is called within + // CBlock::AcceptBlock(), the height of the block *being* + // evaluated is what is used. Thus if we want to know if a + // transaction can be part of the *next* block, we need to call + // IsFinalTx() with one more than chainActive.Height(). + const int nBlockHeight = chainActive.Height() + 1; + + // BIP113 requires that time-locked transactions have nLockTime set to + // less than the median time of the previous block they're contained in. + // When the next block is created its previous block will be the current + // chain tip, so we use that to calculate the median time passed to + // IsFinalTx() if LOCKTIME_MEDIAN_TIME_PAST is set. + const int64_t nBlockTime = (flags & LOCKTIME_MEDIAN_TIME_PAST) + ? chainActive.Tip()->GetMedianTimePast() + : GetAdjustedTime(); + + return IsFinalTx(tx, nBlockHeight, nBlockTime); +} + +bool TestLockPointValidity(const LockPoints* lp) +{ + AssertLockHeld(cs_main); + assert(lp); + // If there are relative lock times then the maxInputBlock will be set + // If there are no relative lock times, the LockPoints don't depend on the chain + if (lp->maxInputBlock) { + // Check whether chainActive is an extension of the block at which the LockPoints + // calculation was valid. If not LockPoints are no longer valid + if (!chainActive.Contains(lp->maxInputBlock)) { + return false; + } + } + + // LockPoints still valid + return true; +} + +bool CheckSequenceLocks(const CTransaction &tx, int flags, LockPoints* lp, bool useExistingLockPoints) +{ + AssertLockHeld(cs_main); + AssertLockHeld(mempool.cs); + + CBlockIndex* tip = chainActive.Tip(); + assert(tip != nullptr); + + CBlockIndex index; + index.pprev = tip; + // CheckSequenceLocks() uses chainActive.Height()+1 to evaluate + // height based locks because when SequenceLocks() is called within + // ConnectBlock(), the height of the block *being* + // evaluated is what is used. + // Thus if we want to know if a transaction can be part of the + // *next* block, we need to use one more than chainActive.Height() + index.nHeight = tip->nHeight + 1; + + std::pair<int, int64_t> lockPair; + if (useExistingLockPoints) { + assert(lp); + lockPair.first = lp->height; + lockPair.second = lp->time; + } + else { + // pcoinsTip contains the UTXO set for chainActive.Tip() + CCoinsViewMemPool viewMemPool(pcoinsTip.get(), mempool); + std::vector<int> prevheights; + prevheights.resize(tx.vin.size()); + for (size_t txinIndex = 0; txinIndex < tx.vin.size(); txinIndex++) { + const CTxIn& txin = tx.vin[txinIndex]; + Coin coin; + if (!viewMemPool.GetCoin(txin.prevout, coin)) { + return error("%s: Missing input", __func__); + } + if (coin.nHeight == MEMPOOL_HEIGHT) { + // Assume all mempool transaction confirm in the next block + prevheights[txinIndex] = tip->nHeight + 1; + } else { + prevheights[txinIndex] = coin.nHeight; + } + } + lockPair = CalculateSequenceLocks(tx, flags, &prevheights, index); + if (lp) { + lp->height = lockPair.first; + lp->time = lockPair.second; + // Also store the hash of the block with the highest height of + // all the blocks which have sequence locked prevouts. + // This hash needs to still be on the chain + // for these LockPoint calculations to be valid + // Note: It is impossible to correctly calculate a maxInputBlock + // if any of the sequence locked inputs depend on unconfirmed txs, + // except in the special case where the relative lock time/height + // is 0, which is equivalent to no sequence lock. Since we assume + // input height of tip+1 for mempool txs and test the resulting + // lockPair from CalculateSequenceLocks against tip+1. We know + // EvaluateSequenceLocks will fail if there was a non-zero sequence + // lock on a mempool input, so we can use the return value of + // CheckSequenceLocks to indicate the LockPoints validity + int maxInputHeight = 0; + for (int height : prevheights) { + // Can ignore mempool inputs since we'll fail if they had non-zero locks + if (height != tip->nHeight+1) { + maxInputHeight = std::max(maxInputHeight, height); + } + } + lp->maxInputBlock = tip->GetAncestor(maxInputHeight); + } + } + return EvaluateSequenceLocks(index, lockPair); +} + +// Returns the script flags which should be checked for a given block +static unsigned int GetBlockScriptFlags(const CBlockIndex* pindex, const Consensus::Params& chainparams); + +static void LimitMempoolSize(CTxMemPool& pool, size_t limit, unsigned long age) { + int expired = pool.Expire(GetTime() - age); + if (expired != 0) { + LogPrint(BCLog::MEMPOOL, "Expired %i transactions from the memory pool\n", expired); + } + + std::vector<COutPoint> vNoSpendsRemaining; + pool.TrimToSize(limit, &vNoSpendsRemaining); + for (const COutPoint& removed : vNoSpendsRemaining) + pcoinsTip->Uncache(removed); +} + +/** Convert CValidationState to a human-readable message for logging */ +std::string FormatStateMessage(const CValidationState &state) +{ + return strprintf("%s%s (code %i)", + state.GetRejectReason(), + state.GetDebugMessage().empty() ? "" : ", "+state.GetDebugMessage(), + state.GetRejectCode()); +} + +static bool IsCurrentForFeeEstimation() +{ + AssertLockHeld(cs_main); + if (IsInitialBlockDownload()) + return false; + if (chainActive.Tip()->GetBlockTime() < (GetTime() - MAX_FEE_ESTIMATION_TIP_AGE)) + return false; + if (chainActive.Height() < pindexBestHeader->nHeight - 1) + return false; + return true; +} + +/* Make mempool consistent after a reorg, by re-adding or recursively erasing + * disconnected block transactions from the mempool, and also removing any + * other transactions from the mempool that are no longer valid given the new + * tip/height. + * + * Note: we assume that disconnectpool only contains transactions that are NOT + * confirmed in the current chain nor already in the mempool (otherwise, + * in-mempool descendants of such transactions would be removed). + * + * Passing fAddToMempool=false will skip trying to add the transactions back, + * and instead just erase from the mempool as needed. + */ + +static void UpdateMempoolForReorg(DisconnectedBlockTransactions &disconnectpool, bool fAddToMempool) +{ + AssertLockHeld(cs_main); + std::vector<uint256> vHashUpdate; + // disconnectpool's insertion_order index sorts the entries from + // oldest to newest, but the oldest entry will be the last tx from the + // latest mined block that was disconnected. + // Iterate disconnectpool in reverse, so that we add transactions + // back to the mempool starting with the earliest transaction that had + // been previously seen in a block. + auto it = disconnectpool.queuedTx.get<insertion_order>().rbegin(); + while (it != disconnectpool.queuedTx.get<insertion_order>().rend()) { + // ignore validation errors in resurrected transactions + CValidationState stateDummy; + if (!fAddToMempool || (*it)->IsCoinBase() || + !AcceptToMemoryPool(mempool, stateDummy, *it, nullptr /* pfMissingInputs */, + nullptr /* plTxnReplaced */, true /* bypass_limits */, 0 /* nAbsurdFee */)) { + // If the transaction doesn't make it in to the mempool, remove any + // transactions that depend on it (which would now be orphans). + mempool.removeRecursive(**it, MemPoolRemovalReason::REORG); + } else if (mempool.exists((*it)->GetHash())) { + vHashUpdate.push_back((*it)->GetHash()); + } + ++it; + } + disconnectpool.queuedTx.clear(); + // AcceptToMemoryPool/addUnchecked all assume that new mempool entries have + // no in-mempool children, which is generally not true when adding + // previously-confirmed transactions back to the mempool. + // UpdateTransactionsFromBlock finds descendants of any transactions in + // the disconnectpool that were added back and cleans up the mempool state. + mempool.UpdateTransactionsFromBlock(vHashUpdate); + + // We also need to remove any now-immature transactions + mempool.removeForReorg(pcoinsTip.get(), chainActive.Tip()->nHeight + 1, STANDARD_LOCKTIME_VERIFY_FLAGS); + // Re-limit mempool size, in case we added any transactions + LimitMempoolSize(mempool, gArgs.GetArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) * 1000000, gArgs.GetArg("-mempoolexpiry", DEFAULT_MEMPOOL_EXPIRY) * 60 * 60); +} + +// Used to avoid mempool polluting consensus critical paths if CCoinsViewMempool +// were somehow broken and returning the wrong scriptPubKeys +static bool CheckInputsFromMempoolAndCache(const CTransaction& tx, CValidationState& state, const CCoinsViewCache& view, const CTxMemPool& pool, + unsigned int flags, bool cacheSigStore, PrecomputedTransactionData& txdata) { + AssertLockHeld(cs_main); + + // pool.cs should be locked already, but go ahead and re-take the lock here + // to enforce that mempool doesn't change between when we check the view + // and when we actually call through to CheckInputs + LOCK(pool.cs); + + assert(!tx.IsCoinBase()); + for (const CTxIn& txin : tx.vin) { + const Coin& coin = view.AccessCoin(txin.prevout); + + // At this point we haven't actually checked if the coins are all + // available (or shouldn't assume we have, since CheckInputs does). + // So we just return failure if the inputs are not available here, + // and then only have to check equivalence for available inputs. + if (coin.IsSpent()) return false; + + const CTransactionRef& txFrom = pool.get(txin.prevout.hash); + if (txFrom) { + assert(txFrom->GetHash() == txin.prevout.hash); + assert(txFrom->vout.size() > txin.prevout.n); + assert(txFrom->vout[txin.prevout.n] == coin.out); + } else { + const Coin& coinFromDisk = pcoinsTip->AccessCoin(txin.prevout); + assert(!coinFromDisk.IsSpent()); + assert(coinFromDisk.out == coin.out); + } + } + + return CheckInputs(tx, state, view, true, flags, cacheSigStore, true, txdata); +} + +static bool AcceptToMemoryPoolWorker(const CChainParams& chainparams, CTxMemPool& pool, CValidationState& state, const CTransactionRef& ptx, + bool* pfMissingInputs, int64_t nAcceptTime, std::list<CTransactionRef>* plTxnReplaced, + bool bypass_limits, const CAmount& nAbsurdFee, std::vector<COutPoint>& coins_to_uncache, bool test_accept) +{ + const CTransaction& tx = *ptx; + const uint256 hash = tx.GetHash(); + AssertLockHeld(cs_main); + LOCK(pool.cs); // mempool "read lock" (held through GetMainSignals().TransactionAddedToMempool()) + if (pfMissingInputs) { + *pfMissingInputs = false; + } + + if (!CheckTransaction(tx, state)) + return false; // state filled in by CheckTransaction + + // Coinbase is only valid in a block, not as a loose transaction + if (tx.IsCoinBase()) + return state.DoS(100, false, REJECT_INVALID, "coinbase"); + + // Rather not work on nonstandard transactions (unless -testnet/-regtest) + std::string reason; + if (fRequireStandard && !IsStandardTx(tx, reason)) + return state.DoS(0, false, REJECT_NONSTANDARD, reason); + + // Do not work on transactions that are too small. + // A transaction with 1 segwit input and 1 P2WPHK output has non-witness size of 82 bytes. + // Transactions smaller than this are not relayed to reduce unnecessary malloc overhead. + if (::GetSerializeSize(tx, SER_NETWORK, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS) < MIN_STANDARD_TX_NONWITNESS_SIZE) + return state.DoS(0, false, REJECT_NONSTANDARD, "tx-size-small"); + + // Only accept nLockTime-using transactions that can be mined in the next + // block; we don't want our mempool filled up with transactions that can't + // be mined yet. + if (!CheckFinalTx(tx, STANDARD_LOCKTIME_VERIFY_FLAGS)) + return state.DoS(0, false, REJECT_NONSTANDARD, "non-final"); + + // is it already in the memory pool? + if (pool.exists(hash)) { + return state.Invalid(false, REJECT_DUPLICATE, "txn-already-in-mempool"); + } + + // Check for conflicts with in-memory transactions + std::set<uint256> setConflicts; + for (const CTxIn &txin : tx.vin) + { + auto itConflicting = pool.mapNextTx.find(txin.prevout); + if (itConflicting != pool.mapNextTx.end()) + { + const CTransaction *ptxConflicting = itConflicting->second; + if (!setConflicts.count(ptxConflicting->GetHash())) + { + // Allow opt-out of transaction replacement by setting + // nSequence > MAX_BIP125_RBF_SEQUENCE (SEQUENCE_FINAL-2) on all inputs. + // + // SEQUENCE_FINAL-1 is picked to still allow use of nLockTime by + // non-replaceable transactions. All inputs rather than just one + // is for the sake of multi-party protocols, where we don't + // want a single party to be able to disable replacement. + // + // The opt-out ignores descendants as anyone relying on + // first-seen mempool behavior should be checking all + // unconfirmed ancestors anyway; doing otherwise is hopelessly + // insecure. + bool fReplacementOptOut = true; + if (fEnableReplacement) + { + for (const CTxIn &_txin : ptxConflicting->vin) + { + if (_txin.nSequence <= MAX_BIP125_RBF_SEQUENCE) + { + fReplacementOptOut = false; + break; + } + } + } + if (fReplacementOptOut) { + return state.Invalid(false, REJECT_DUPLICATE, "txn-mempool-conflict"); + } + + setConflicts.insert(ptxConflicting->GetHash()); + } + } + } + + { + CCoinsView dummy; + CCoinsViewCache view(&dummy); + + LockPoints lp; + CCoinsViewMemPool viewMemPool(pcoinsTip.get(), pool); + view.SetBackend(viewMemPool); + + // do all inputs exist? + for (const CTxIn& txin : tx.vin) { + if (!pcoinsTip->HaveCoinInCache(txin.prevout)) { + coins_to_uncache.push_back(txin.prevout); + } + if (!view.HaveCoin(txin.prevout)) { + // Are inputs missing because we already have the tx? + for (size_t out = 0; out < tx.vout.size(); out++) { + // Optimistically just do efficient check of cache for outputs + if (pcoinsTip->HaveCoinInCache(COutPoint(hash, out))) { + return state.Invalid(false, REJECT_DUPLICATE, "txn-already-known"); + } + } + // Otherwise assume this might be an orphan tx for which we just haven't seen parents yet + if (pfMissingInputs) { + *pfMissingInputs = true; + } + return false; // fMissingInputs and !state.IsInvalid() is used to detect this condition, don't set state.Invalid() + } + } + + // Bring the best block into scope + view.GetBestBlock(); + + // we have all inputs cached now, so switch back to dummy, so we don't need to keep lock on mempool + view.SetBackend(dummy); + + // Only accept BIP68 sequence locked transactions that can be mined in the next + // block; we don't want our mempool filled up with transactions that can't + // be mined yet. + // Must keep pool.cs for this unless we change CheckSequenceLocks to take a + // CoinsViewCache instead of create its own + if (!CheckSequenceLocks(tx, STANDARD_LOCKTIME_VERIFY_FLAGS, &lp)) + return state.DoS(0, false, REJECT_NONSTANDARD, "non-BIP68-final"); + + CAmount nFees = 0; + if (!Consensus::CheckTxInputs(tx, state, view, GetSpendHeight(view), nFees)) { + return error("%s: Consensus::CheckTxInputs: %s, %s", __func__, tx.GetHash().ToString(), FormatStateMessage(state)); + } + + // Check for non-standard pay-to-script-hash in inputs + if (fRequireStandard && !AreInputsStandard(tx, view)) + return state.Invalid(false, REJECT_NONSTANDARD, "bad-txns-nonstandard-inputs"); + + // Check for non-standard witness in P2WSH + if (tx.HasWitness() && fRequireStandard && !IsWitnessStandard(tx, view)) + return state.DoS(0, false, REJECT_NONSTANDARD, "bad-witness-nonstandard", true); + + int64_t nSigOpsCost = GetTransactionSigOpCost(tx, view, STANDARD_SCRIPT_VERIFY_FLAGS); + + // nModifiedFees includes any fee deltas from PrioritiseTransaction + CAmount nModifiedFees = nFees; + pool.ApplyDelta(hash, nModifiedFees); + + // Keep track of transactions that spend a coinbase, which we re-scan + // during reorgs to ensure COINBASE_MATURITY is still met. + bool fSpendsCoinbase = false; + for (const CTxIn &txin : tx.vin) { + const Coin &coin = view.AccessCoin(txin.prevout); + if (coin.IsCoinBase()) { + fSpendsCoinbase = true; + break; + } + } + + CTxMemPoolEntry entry(ptx, nFees, nAcceptTime, chainActive.Height(), + fSpendsCoinbase, nSigOpsCost, lp); + unsigned int nSize = entry.GetTxSize(); + + // Check that the transaction doesn't have an excessive number of + // sigops, making it impossible to mine. Since the coinbase transaction + // itself can contain sigops MAX_STANDARD_TX_SIGOPS is less than + // MAX_BLOCK_SIGOPS; we still consider this an invalid rather than + // merely non-standard transaction. + if (nSigOpsCost > MAX_STANDARD_TX_SIGOPS_COST) + return state.DoS(0, false, REJECT_NONSTANDARD, "bad-txns-too-many-sigops", false, + strprintf("%d", nSigOpsCost)); + + CAmount mempoolRejectFee = pool.GetMinFee(gArgs.GetArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) * 1000000).GetFee(nSize); + if (!bypass_limits && mempoolRejectFee > 0 && nModifiedFees < mempoolRejectFee) { + return state.DoS(0, false, REJECT_INSUFFICIENTFEE, "mempool min fee not met", false, strprintf("%d < %d", nModifiedFees, mempoolRejectFee)); + } + + // No transactions are allowed below minRelayTxFee except from disconnected blocks + if (!bypass_limits && nModifiedFees < ::minRelayTxFee.GetFee(nSize)) { + return state.DoS(0, false, REJECT_INSUFFICIENTFEE, "min relay fee not met", false, strprintf("%d < %d", nModifiedFees, ::minRelayTxFee.GetFee(nSize))); + } + + if (nAbsurdFee && nFees > nAbsurdFee) + return state.Invalid(false, + REJECT_HIGHFEE, "absurdly-high-fee", + strprintf("%d > %d", nFees, nAbsurdFee)); + + // Calculate in-mempool ancestors, up to a limit. + CTxMemPool::setEntries setAncestors; + size_t nLimitAncestors = gArgs.GetArg("-limitancestorcount", DEFAULT_ANCESTOR_LIMIT); + size_t nLimitAncestorSize = gArgs.GetArg("-limitancestorsize", DEFAULT_ANCESTOR_SIZE_LIMIT)*1000; + size_t nLimitDescendants = gArgs.GetArg("-limitdescendantcount", DEFAULT_DESCENDANT_LIMIT); + size_t nLimitDescendantSize = gArgs.GetArg("-limitdescendantsize", DEFAULT_DESCENDANT_SIZE_LIMIT)*1000; + std::string errString; + if (!pool.CalculateMemPoolAncestors(entry, setAncestors, nLimitAncestors, nLimitAncestorSize, nLimitDescendants, nLimitDescendantSize, errString)) { + return state.DoS(0, false, REJECT_NONSTANDARD, "too-long-mempool-chain", false, errString); + } + + // A transaction that spends outputs that would be replaced by it is invalid. Now + // that we have the set of all ancestors we can detect this + // pathological case by making sure setConflicts and setAncestors don't + // intersect. + for (CTxMemPool::txiter ancestorIt : setAncestors) + { + const uint256 &hashAncestor = ancestorIt->GetTx().GetHash(); + if (setConflicts.count(hashAncestor)) + { + return state.DoS(10, false, + REJECT_INVALID, "bad-txns-spends-conflicting-tx", false, + strprintf("%s spends conflicting transaction %s", + hash.ToString(), + hashAncestor.ToString())); + } + } + + // Check if it's economically rational to mine this transaction rather + // than the ones it replaces. + CAmount nConflictingFees = 0; + size_t nConflictingSize = 0; + uint64_t nConflictingCount = 0; + CTxMemPool::setEntries allConflicting; + + // If we don't hold the lock allConflicting might be incomplete; the + // subsequent RemoveStaged() and addUnchecked() calls don't guarantee + // mempool consistency for us. + const bool fReplacementTransaction = setConflicts.size(); + if (fReplacementTransaction) + { + CFeeRate newFeeRate(nModifiedFees, nSize); + std::set<uint256> setConflictsParents; + const int maxDescendantsToVisit = 100; + CTxMemPool::setEntries setIterConflicting; + for (const uint256 &hashConflicting : setConflicts) + { + CTxMemPool::txiter mi = pool.mapTx.find(hashConflicting); + if (mi == pool.mapTx.end()) + continue; + + // Save these to avoid repeated lookups + setIterConflicting.insert(mi); + + // Don't allow the replacement to reduce the feerate of the + // mempool. + // + // We usually don't want to accept replacements with lower + // feerates than what they replaced as that would lower the + // feerate of the next block. Requiring that the feerate always + // be increased is also an easy-to-reason about way to prevent + // DoS attacks via replacements. + // + // We only consider the feerates of transactions being directly + // replaced, not their indirect descendants. While that does + // mean high feerate children are ignored when deciding whether + // or not to replace, we do require the replacement to pay more + // overall fees too, mitigating most cases. + CFeeRate oldFeeRate(mi->GetModifiedFee(), mi->GetTxSize()); + if (newFeeRate <= oldFeeRate) + { + return state.DoS(0, false, + REJECT_INSUFFICIENTFEE, "insufficient fee", false, + strprintf("rejecting replacement %s; new feerate %s <= old feerate %s", + hash.ToString(), + newFeeRate.ToString(), + oldFeeRate.ToString())); + } + + for (const CTxIn &txin : mi->GetTx().vin) + { + setConflictsParents.insert(txin.prevout.hash); + } + + nConflictingCount += mi->GetCountWithDescendants(); + } + // This potentially overestimates the number of actual descendants + // but we just want to be conservative to avoid doing too much + // work. + if (nConflictingCount <= maxDescendantsToVisit) { + // If not too many to replace, then calculate the set of + // transactions that would have to be evicted + for (CTxMemPool::txiter it : setIterConflicting) { + pool.CalculateDescendants(it, allConflicting); + } + for (CTxMemPool::txiter it : allConflicting) { + nConflictingFees += it->GetModifiedFee(); + nConflictingSize += it->GetTxSize(); + } + } else { + return state.DoS(0, false, + REJECT_NONSTANDARD, "too many potential replacements", false, + strprintf("rejecting replacement %s; too many potential replacements (%d > %d)\n", + hash.ToString(), + nConflictingCount, + maxDescendantsToVisit)); + } + + for (unsigned int j = 0; j < tx.vin.size(); j++) + { + // We don't want to accept replacements that require low + // feerate junk to be mined first. Ideally we'd keep track of + // the ancestor feerates and make the decision based on that, + // but for now requiring all new inputs to be confirmed works. + if (!setConflictsParents.count(tx.vin[j].prevout.hash)) + { + // Rather than check the UTXO set - potentially expensive - + // it's cheaper to just check if the new input refers to a + // tx that's in the mempool. + if (pool.mapTx.find(tx.vin[j].prevout.hash) != pool.mapTx.end()) + return state.DoS(0, false, + REJECT_NONSTANDARD, "replacement-adds-unconfirmed", false, + strprintf("replacement %s adds unconfirmed input, idx %d", + hash.ToString(), j)); + } + } + + // The replacement must pay greater fees than the transactions it + // replaces - if we did the bandwidth used by those conflicting + // transactions would not be paid for. + if (nModifiedFees < nConflictingFees) + { + return state.DoS(0, false, + REJECT_INSUFFICIENTFEE, "insufficient fee", false, + strprintf("rejecting replacement %s, less fees than conflicting txs; %s < %s", + hash.ToString(), FormatMoney(nModifiedFees), FormatMoney(nConflictingFees))); + } + + // Finally in addition to paying more fees than the conflicts the + // new transaction must pay for its own bandwidth. + CAmount nDeltaFees = nModifiedFees - nConflictingFees; + if (nDeltaFees < ::incrementalRelayFee.GetFee(nSize)) + { + return state.DoS(0, false, + REJECT_INSUFFICIENTFEE, "insufficient fee", false, + strprintf("rejecting replacement %s, not enough additional fees to relay; %s < %s", + hash.ToString(), + FormatMoney(nDeltaFees), + FormatMoney(::incrementalRelayFee.GetFee(nSize)))); + } + } + + constexpr unsigned int scriptVerifyFlags = STANDARD_SCRIPT_VERIFY_FLAGS; + + // 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, 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, 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 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 (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 (!CheckInputsFromMempoolAndCache(tx, state, view, pool, currentBlockScriptVerifyFlags, true, txdata)) { + return error("%s: BUG! PLEASE REPORT THIS! CheckInputs failed against latest-block but not STANDARD flags %s, %s", + __func__, hash.ToString(), FormatStateMessage(state)); + } + + if (test_accept) { + // Tx was accepted, but not added + return true; + } + + // Remove conflicting transactions from the mempool + for (CTxMemPool::txiter it : allConflicting) + { + LogPrint(BCLog::MEMPOOL, "replacing tx %s with %s for %s BTC additional fees, %d delta bytes\n", + it->GetTx().GetHash().ToString(), + hash.ToString(), + FormatMoney(nModifiedFees - nConflictingFees), + (int)nSize - (int)nConflictingSize); + if (plTxnReplaced) + plTxnReplaced->push_back(it->GetSharedTx()); + } + pool.RemoveStaged(allConflicting, false, MemPoolRemovalReason::REPLACED); + + // This transaction should only count for fee estimation if: + // - it isn't a BIP 125 replacement transaction (may not be widely supported) + // - it's not being re-added during a reorg which bypasses typical mempool fee limits + // - the node is not behind + // - the transaction is not dependent on any other transactions in the mempool + bool validForFeeEstimation = !fReplacementTransaction && !bypass_limits && IsCurrentForFeeEstimation() && pool.HasNoInputsOf(tx); + + // Store transaction in memory + pool.addUnchecked(hash, entry, setAncestors, validForFeeEstimation); + + // trim mempool and check if tx was trimmed + if (!bypass_limits) { + LimitMempoolSize(pool, gArgs.GetArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) * 1000000, gArgs.GetArg("-mempoolexpiry", DEFAULT_MEMPOOL_EXPIRY) * 60 * 60); + if (!pool.exists(hash)) + return state.DoS(0, false, REJECT_INSUFFICIENTFEE, "mempool full"); + } + } + + GetMainSignals().TransactionAddedToMempool(ptx); + + return true; +} + +/** (try to) add transaction to memory pool with a specified acceptance time **/ +static bool AcceptToMemoryPoolWithTime(const CChainParams& chainparams, CTxMemPool& pool, CValidationState &state, const CTransactionRef &tx, + bool* pfMissingInputs, int64_t nAcceptTime, std::list<CTransactionRef>* plTxnReplaced, + bool bypass_limits, const CAmount nAbsurdFee, bool test_accept) +{ + std::vector<COutPoint> coins_to_uncache; + bool res = AcceptToMemoryPoolWorker(chainparams, pool, state, tx, pfMissingInputs, nAcceptTime, plTxnReplaced, bypass_limits, nAbsurdFee, coins_to_uncache, test_accept); + if (!res) { + for (const COutPoint& hashTx : coins_to_uncache) + pcoinsTip->Uncache(hashTx); + } + // After we've (potentially) uncached entries, ensure our coins cache is still within its size limits + CValidationState stateDummy; + FlushStateToDisk(chainparams, stateDummy, FlushStateMode::PERIODIC); + return res; +} + +bool AcceptToMemoryPool(CTxMemPool& pool, CValidationState &state, const CTransactionRef &tx, + bool* pfMissingInputs, std::list<CTransactionRef>* plTxnReplaced, + bool bypass_limits, const CAmount nAbsurdFee, bool test_accept) +{ + const CChainParams& chainparams = Params(); + return AcceptToMemoryPoolWithTime(chainparams, pool, state, tx, pfMissingInputs, GetTime(), plTxnReplaced, bypass_limits, nAbsurdFee, test_accept); +} + +/** + * Return transaction in txOut, and if it was found inside a block, its hash is placed in hashBlock. + * If blockIndex is provided, the transaction is fetched from the corresponding block. + */ +bool GetTransaction(const uint256& hash, CTransactionRef& txOut, const Consensus::Params& consensusParams, uint256& hashBlock, bool fAllowSlow, CBlockIndex* blockIndex) +{ + CBlockIndex* pindexSlow = blockIndex; + + LOCK(cs_main); + + if (!blockIndex) { + CTransactionRef ptx = mempool.get(hash); + if (ptx) { + txOut = ptx; + return true; + } + + if (g_txindex) { + return g_txindex->FindTx(hash, hashBlock, txOut); + } + + if (fAllowSlow) { // use coin database to locate block that contains transaction, and scan it + const Coin& coin = AccessByTxid(*pcoinsTip, hash); + if (!coin.IsSpent()) pindexSlow = chainActive[coin.nHeight]; + } + } + + if (pindexSlow) { + CBlock block; + if (ReadBlockFromDisk(block, pindexSlow, consensusParams)) { + for (const auto& tx : block.vtx) { + if (tx->GetHash() == hash) { + txOut = tx; + hashBlock = pindexSlow->GetBlockHash(); + return true; + } + } + } + } + + return false; +} + + + + + + +////////////////////////////////////////////////////////////////////////////// +// +// CBlock and CBlockIndex +// + +static bool WriteBlockToDisk(const CBlock& block, CDiskBlockPos& pos, const CMessageHeader::MessageStartChars& messageStart) +{ + // Open history file to append + CAutoFile fileout(OpenBlockFile(pos), SER_DISK, CLIENT_VERSION); + if (fileout.IsNull()) + return error("WriteBlockToDisk: OpenBlockFile failed"); + + // Write index header + unsigned int nSize = GetSerializeSize(fileout, block); + fileout << messageStart << nSize; + + // Write block + long fileOutPos = ftell(fileout.Get()); + if (fileOutPos < 0) + return error("WriteBlockToDisk: ftell failed"); + pos.nPos = (unsigned int)fileOutPos; + fileout << block; + + return true; +} + +bool ReadBlockFromDisk(CBlock& block, const CDiskBlockPos& pos, const Consensus::Params& consensusParams) +{ + block.SetNull(); + + // Open history file to read + CAutoFile filein(OpenBlockFile(pos, true), SER_DISK, CLIENT_VERSION); + if (filein.IsNull()) + return error("ReadBlockFromDisk: OpenBlockFile failed for %s", pos.ToString()); + + // Read block + try { + filein >> block; + } + catch (const std::exception& e) { + return error("%s: Deserialize or I/O error - %s at %s", __func__, e.what(), pos.ToString()); + } + + // Check the header + if (!CheckProofOfWork(block.GetHash(), block.nBits, consensusParams)) + return error("ReadBlockFromDisk: Errors in block header at %s", pos.ToString()); + + return true; +} + +bool ReadBlockFromDisk(CBlock& block, const CBlockIndex* pindex, const Consensus::Params& consensusParams) +{ + CDiskBlockPos blockPos; + { + LOCK(cs_main); + blockPos = pindex->GetBlockPos(); + } + + if (!ReadBlockFromDisk(block, blockPos, consensusParams)) + return false; + if (block.GetHash() != pindex->GetBlockHash()) + return error("ReadBlockFromDisk(CBlock&, CBlockIndex*): GetHash() doesn't match index for %s at %s", + pindex->ToString(), pindex->GetBlockPos().ToString()); + return true; +} + +bool ReadRawBlockFromDisk(std::vector<uint8_t>& block, const CDiskBlockPos& pos, const CMessageHeader::MessageStartChars& message_start) +{ + CDiskBlockPos hpos = pos; + hpos.nPos -= 8; // Seek back 8 bytes for meta header + CAutoFile filein(OpenBlockFile(hpos, true), SER_DISK, CLIENT_VERSION); + if (filein.IsNull()) { + return error("%s: OpenBlockFile failed for %s", __func__, pos.ToString()); + } + + try { + CMessageHeader::MessageStartChars blk_start; + unsigned int blk_size; + + filein >> blk_start >> blk_size; + + if (memcmp(blk_start, message_start, CMessageHeader::MESSAGE_START_SIZE)) { + return error("%s: Block magic mismatch for %s: %s versus expected %s", __func__, pos.ToString(), + HexStr(blk_start, blk_start + CMessageHeader::MESSAGE_START_SIZE), + HexStr(message_start, message_start + CMessageHeader::MESSAGE_START_SIZE)); + } + + if (blk_size > MAX_SIZE) { + return error("%s: Block data is larger than maximum deserialization size for %s: %s versus %s", __func__, pos.ToString(), + blk_size, MAX_SIZE); + } + + block.resize(blk_size); // Zeroing of memory is intentional here + filein.read((char*)block.data(), blk_size); + } catch(const std::exception& e) { + return error("%s: Read from block file failed: %s for %s", __func__, e.what(), pos.ToString()); + } + + return true; +} + +bool ReadRawBlockFromDisk(std::vector<uint8_t>& block, const CBlockIndex* pindex, const CMessageHeader::MessageStartChars& message_start) +{ + CDiskBlockPos block_pos; + { + LOCK(cs_main); + block_pos = pindex->GetBlockPos(); + } + + return ReadRawBlockFromDisk(block, block_pos, message_start); +} + +CAmount GetBlockSubsidy(int nHeight, const Consensus::Params& consensusParams) +{ + int halvings = nHeight / consensusParams.nSubsidyHalvingInterval; + // Force block reward to zero when right shift is undefined. + if (halvings >= 64) + return 0; + + CAmount nSubsidy = 50 * COIN; + // Subsidy is cut in half every 210,000 blocks which will occur approximately every 4 years. + nSubsidy >>= halvings; + return nSubsidy; +} + +bool IsInitialBlockDownload() +{ + // Once this function has returned false, it must remain false. + static std::atomic<bool> latchToFalse{false}; + // Optimization: pre-test latch before taking the lock. + if (latchToFalse.load(std::memory_order_relaxed)) + return false; + + LOCK(cs_main); + if (latchToFalse.load(std::memory_order_relaxed)) + return false; + if (fImporting || fReindex) + return true; + if (chainActive.Tip() == nullptr) + return true; + if (chainActive.Tip()->nChainWork < nMinimumChainWork) + return true; + if (chainActive.Tip()->GetBlockTime() < (GetTime() - nMaxTipAge)) + return true; + LogPrintf("Leaving InitialBlockDownload (latching to false)\n"); + latchToFalse.store(true, std::memory_order_relaxed); + return false; +} + +CBlockIndex *pindexBestForkTip = nullptr, *pindexBestForkBase = nullptr; + +static void AlertNotify(const std::string& strMessage) +{ + uiInterface.NotifyAlertChanged(); + std::string strCmd = gArgs.GetArg("-alertnotify", ""); + if (strCmd.empty()) return; + + // Alert text should be plain ascii coming from a trusted source, but to + // be safe we first strip anything not in safeChars, then add single quotes around + // the whole string before passing it to the shell: + std::string singleQuote("'"); + std::string safeStatus = SanitizeString(strMessage); + safeStatus = singleQuote+safeStatus+singleQuote; + boost::replace_all(strCmd, "%s", safeStatus); + + std::thread t(runCommand, strCmd); + t.detach(); // thread runs free +} + +static void CheckForkWarningConditions() +{ + AssertLockHeld(cs_main); + // Before we get past initial download, we cannot reliably alert about forks + // (we assume we don't get stuck on a fork before finishing our initial sync) + if (IsInitialBlockDownload()) + return; + + // If our best fork is no longer within 72 blocks (+/- 12 hours if no one mines it) + // of our head, drop it + if (pindexBestForkTip && chainActive.Height() - pindexBestForkTip->nHeight >= 72) + pindexBestForkTip = nullptr; + + if (pindexBestForkTip || (pindexBestInvalid && pindexBestInvalid->nChainWork > chainActive.Tip()->nChainWork + (GetBlockProof(*chainActive.Tip()) * 6))) + { + if (!GetfLargeWorkForkFound() && pindexBestForkBase) + { + std::string warning = std::string("'Warning: Large-work fork detected, forking after block ") + + pindexBestForkBase->phashBlock->ToString() + std::string("'"); + AlertNotify(warning); + } + if (pindexBestForkTip && pindexBestForkBase) + { + LogPrintf("%s: Warning: Large valid fork found\n forking the chain at height %d (%s)\n lasting to height %d (%s).\nChain state database corruption likely.\n", __func__, + pindexBestForkBase->nHeight, pindexBestForkBase->phashBlock->ToString(), + pindexBestForkTip->nHeight, pindexBestForkTip->phashBlock->ToString()); + SetfLargeWorkForkFound(true); + } + else + { + LogPrintf("%s: Warning: Found invalid chain at least ~6 blocks longer than our best chain.\nChain state database corruption likely.\n", __func__); + SetfLargeWorkInvalidChainFound(true); + } + } + else + { + SetfLargeWorkForkFound(false); + SetfLargeWorkInvalidChainFound(false); + } +} + +static void CheckForkWarningConditionsOnNewFork(CBlockIndex* pindexNewForkTip) +{ + AssertLockHeld(cs_main); + // If we are on a fork that is sufficiently large, set a warning flag + CBlockIndex* pfork = pindexNewForkTip; + CBlockIndex* plonger = chainActive.Tip(); + while (pfork && pfork != plonger) + { + while (plonger && plonger->nHeight > pfork->nHeight) + plonger = plonger->pprev; + if (pfork == plonger) + break; + pfork = pfork->pprev; + } + + // We define a condition where we should warn the user about as a fork of at least 7 blocks + // with a tip within 72 blocks (+/- 12 hours if no one mines it) of ours + // We use 7 blocks rather arbitrarily as it represents just under 10% of sustained network + // hash rate operating on the fork. + // or a chain that is entirely longer than ours and invalid (note that this should be detected by both) + // We define it this way because it allows us to only store the highest fork tip (+ base) which meets + // the 7-block condition and from this always have the most-likely-to-cause-warning fork + if (pfork && (!pindexBestForkTip || pindexNewForkTip->nHeight > pindexBestForkTip->nHeight) && + pindexNewForkTip->nChainWork - pfork->nChainWork > (GetBlockProof(*pfork) * 7) && + chainActive.Height() - pindexNewForkTip->nHeight < 72) + { + pindexBestForkTip = pindexNewForkTip; + pindexBestForkBase = pfork; + } + + CheckForkWarningConditions(); +} + +void static InvalidChainFound(CBlockIndex* pindexNew) +{ + if (!pindexBestInvalid || pindexNew->nChainWork > pindexBestInvalid->nChainWork) + pindexBestInvalid = pindexNew; + + LogPrintf("%s: invalid block=%s height=%d log2_work=%.8g date=%s\n", __func__, + pindexNew->GetBlockHash().ToString(), pindexNew->nHeight, + log(pindexNew->nChainWork.getdouble())/log(2.0), FormatISO8601DateTime(pindexNew->GetBlockTime())); + CBlockIndex *tip = chainActive.Tip(); + assert (tip); + LogPrintf("%s: current best=%s height=%d log2_work=%.8g date=%s\n", __func__, + tip->GetBlockHash().ToString(), chainActive.Height(), log(tip->nChainWork.getdouble())/log(2.0), + FormatISO8601DateTime(tip->GetBlockTime())); + CheckForkWarningConditions(); +} + +void CChainState::InvalidBlockFound(CBlockIndex *pindex, const CValidationState &state) { + if (!state.CorruptionPossible()) { + pindex->nStatus |= BLOCK_FAILED_VALID; + m_failed_blocks.insert(pindex); + setDirtyBlockIndex.insert(pindex); + setBlockIndexCandidates.erase(pindex); + InvalidChainFound(pindex); + } +} + +void UpdateCoins(const CTransaction& tx, CCoinsViewCache& inputs, CTxUndo &txundo, int nHeight) +{ + // mark inputs spent + if (!tx.IsCoinBase()) { + txundo.vprevout.reserve(tx.vin.size()); + for (const CTxIn &txin : tx.vin) { + txundo.vprevout.emplace_back(); + bool is_spent = inputs.SpendCoin(txin.prevout, &txundo.vprevout.back()); + assert(is_spent); + } + } + // add outputs + AddCoins(inputs, tx, nHeight); +} + +void UpdateCoins(const CTransaction& tx, CCoinsViewCache& inputs, int nHeight) +{ + CTxUndo txundo; + UpdateCoins(tx, inputs, txundo, nHeight); +} + +bool CScriptCheck::operator()() { + const CScript &scriptSig = ptxTo->vin[nIn].scriptSig; + const CScriptWitness *witness = &ptxTo->vin[nIn].scriptWitness; + return VerifyScript(scriptSig, m_tx_out.scriptPubKey, witness, nFlags, CachingTransactionSignatureChecker(ptxTo, nIn, m_tx_out.nValue, cacheStore, *txdata), &error); +} + +int GetSpendHeight(const CCoinsViewCache& inputs) +{ + LOCK(cs_main); + CBlockIndex* pindexPrev = LookupBlockIndex(inputs.GetBestBlock()); + 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, gArgs.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/2 requested for script execution cache, able to store %zu elements\n", + (nElems*sizeof(uint256)) >>20, (nMaxCacheSize*2)>>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 nullptr, script checks are pushed onto it instead of being performed inline. Any + * script checks which are not necessary (eg due to script execution cache hits) are, obviously, + * not pushed onto pvChecks/run. + * + * Setting cacheSigStore/cacheFullScriptStore to false will remove elements from the corresponding cache + * which are matched. This is useful for checking blocks where we will likely never need the cache + * entry again. + * + * Non-static (and re-declared) in src/test/txvalidationcache_tests.cpp + */ +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()) + { + if (pvChecks) + pvChecks->reserve(tx.vin.size()); + + // The first loop above does all the inexpensive checks. + // Only if ALL inputs pass do we perform expensive ECDSA signature checks. + // Helps prevent CPU exhaustion attacks. + + // Skip script verification when connecting blocks under the + // assumevalid block. Assuming the assumevalid block is valid this + // is safe because block merkle hashes are still computed and checked, + // 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); + assert(!coin.IsSpent()); + + // We very carefully only pass in things to CScriptCheck which + // are clearly committed to by tx' witness hash. This provides + // a sanity check that our caching is not introducing consensus + // failures through additional data in, eg, the coins being + // spent being checked as a part of CScriptCheck. + + // Verify signature + CScriptCheck check(coin.out, tx, i, flags, cacheSigStore, &txdata); + if (pvChecks) { + pvChecks->push_back(CScriptCheck()); + check.swap(pvChecks->back()); + } else if (!check()) { + 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 check2(coin.out, tx, i, + 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()))); + } + // Failures of other flags indicate a transaction that is + // invalid in new blocks, e.g. an 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 soft-fork + // super-majority signaling has occurred. + 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); + } + } + } + + return true; +} + +namespace { + +bool UndoWriteToDisk(const CBlockUndo& blockundo, CDiskBlockPos& pos, const uint256& hashBlock, const CMessageHeader::MessageStartChars& messageStart) +{ + // Open history file to append + CAutoFile fileout(OpenUndoFile(pos), SER_DISK, CLIENT_VERSION); + if (fileout.IsNull()) + return error("%s: OpenUndoFile failed", __func__); + + // Write index header + unsigned int nSize = GetSerializeSize(fileout, blockundo); + fileout << messageStart << nSize; + + // Write undo data + long fileOutPos = ftell(fileout.Get()); + if (fileOutPos < 0) + return error("%s: ftell failed", __func__); + pos.nPos = (unsigned int)fileOutPos; + fileout << blockundo; + + // calculate & write checksum + CHashWriter hasher(SER_GETHASH, PROTOCOL_VERSION); + hasher << hashBlock; + hasher << blockundo; + fileout << hasher.GetHash(); + + return true; +} + +static bool UndoReadFromDisk(CBlockUndo& blockundo, const CBlockIndex *pindex) +{ + CDiskBlockPos pos = pindex->GetUndoPos(); + if (pos.IsNull()) { + return error("%s: no undo data available", __func__); + } + + // Open history file to read + CAutoFile filein(OpenUndoFile(pos, true), SER_DISK, CLIENT_VERSION); + if (filein.IsNull()) + return error("%s: OpenUndoFile failed", __func__); + + // Read block + uint256 hashChecksum; + CHashVerifier<CAutoFile> verifier(&filein); // We need a CHashVerifier as reserializing may lose data + try { + verifier << pindex->pprev->GetBlockHash(); + verifier >> blockundo; + filein >> hashChecksum; + } + catch (const std::exception& e) { + return error("%s: Deserialize or I/O error - %s", __func__, e.what()); + } + + // Verify checksum + if (hashChecksum != verifier.GetHash()) + return error("%s: Checksum mismatch", __func__); + + return true; +} + +/** Abort with a message */ +static bool AbortNode(const std::string& strMessage, const std::string& userMessage="") +{ + SetMiscWarning(strMessage); + LogPrintf("*** %s\n", strMessage); + uiInterface.ThreadSafeMessageBox( + userMessage.empty() ? _("Error: A fatal internal error occurred, see debug.log for details") : userMessage, + "", CClientUIInterface::MSG_ERROR); + StartShutdown(); + return false; +} + +static bool AbortNode(CValidationState& state, const std::string& strMessage, const std::string& userMessage="") +{ + AbortNode(strMessage, userMessage); + return state.Error(strMessage); +} + +} // namespace + +/** + * Restore the UTXO in a Coin at a given COutPoint + * @param undo The Coin to be restored. + * @param view The coins view to which to apply the changes. + * @param out The out point that corresponds to the tx input. + * @return A DisconnectResult as an int + */ +int ApplyTxInUndo(Coin&& undo, CCoinsViewCache& view, const COutPoint& out) +{ + bool fClean = true; + + if (view.HaveCoin(out)) fClean = false; // overwriting transaction output + + if (undo.nHeight == 0) { + // Missing undo metadata (height and coinbase). Older versions included this + // information only in undo records for the last spend of a transactions' + // outputs. This implies that it must be present for some other output of the same tx. + const Coin& alternate = AccessByTxid(view, out.hash); + if (!alternate.IsSpent()) { + undo.nHeight = alternate.nHeight; + undo.fCoinBase = alternate.fCoinBase; + } else { + return DISCONNECT_FAILED; // adding output for transaction without known metadata + } + } + // The potential_overwrite parameter to AddCoin is only allowed to be false if we know for + // sure that the coin did not already exist in the cache. As we have queried for that above + // using HaveCoin, we don't need to guess. When fClean is false, a coin already existed and + // it is an overwrite. + view.AddCoin(out, std::move(undo), !fClean); + + return fClean ? DISCONNECT_OK : DISCONNECT_UNCLEAN; +} + +/** Undo the effects of this block (with given index) on the UTXO set represented by coins. + * When FAILED is returned, view is left in an indeterminate state. */ +DisconnectResult CChainState::DisconnectBlock(const CBlock& block, const CBlockIndex* pindex, CCoinsViewCache& view) +{ + bool fClean = true; + + CBlockUndo blockUndo; + if (!UndoReadFromDisk(blockUndo, pindex)) { + error("DisconnectBlock(): failure reading undo data"); + return DISCONNECT_FAILED; + } + + if (blockUndo.vtxundo.size() + 1 != block.vtx.size()) { + error("DisconnectBlock(): block and undo data inconsistent"); + return DISCONNECT_FAILED; + } + + // undo transactions in reverse order + for (int i = block.vtx.size() - 1; i >= 0; i--) { + const CTransaction &tx = *(block.vtx[i]); + uint256 hash = tx.GetHash(); + bool is_coinbase = tx.IsCoinBase(); + + // Check that all outputs are available and match the outputs in the block itself + // exactly. + for (size_t o = 0; o < tx.vout.size(); o++) { + if (!tx.vout[o].scriptPubKey.IsUnspendable()) { + COutPoint out(hash, o); + Coin coin; + bool is_spent = view.SpendCoin(out, &coin); + if (!is_spent || tx.vout[o] != coin.out || pindex->nHeight != coin.nHeight || is_coinbase != coin.fCoinBase) { + fClean = false; // transaction output mismatch + } + } + } + + // restore inputs + if (i > 0) { // not coinbases + CTxUndo &txundo = blockUndo.vtxundo[i-1]; + if (txundo.vprevout.size() != tx.vin.size()) { + error("DisconnectBlock(): transaction and undo data inconsistent"); + return DISCONNECT_FAILED; + } + for (unsigned int j = tx.vin.size(); j-- > 0;) { + const COutPoint &out = tx.vin[j].prevout; + int res = ApplyTxInUndo(std::move(txundo.vprevout[j]), view, out); + if (res == DISCONNECT_FAILED) return DISCONNECT_FAILED; + fClean = fClean && res != DISCONNECT_UNCLEAN; + } + // At this point, all of txundo.vprevout should have been moved out. + } + } + + // move best block pointer to prevout block + view.SetBestBlock(pindex->pprev->GetBlockHash()); + + return fClean ? DISCONNECT_OK : DISCONNECT_UNCLEAN; +} + +void static FlushBlockFile(bool fFinalize = false) +{ + LOCK(cs_LastBlockFile); + + CDiskBlockPos posOld(nLastBlockFile, 0); + bool status = true; + + FILE *fileOld = OpenBlockFile(posOld); + if (fileOld) { + if (fFinalize) + status &= TruncateFile(fileOld, vinfoBlockFile[nLastBlockFile].nSize); + status &= FileCommit(fileOld); + fclose(fileOld); + } + + fileOld = OpenUndoFile(posOld); + if (fileOld) { + if (fFinalize) + status &= TruncateFile(fileOld, vinfoBlockFile[nLastBlockFile].nUndoSize); + status &= FileCommit(fileOld); + fclose(fileOld); + } + + if (!status) { + AbortNode("Flushing block file to disk failed. This is likely the result of an I/O error."); + } +} + +static bool FindUndoPos(CValidationState &state, int nFile, CDiskBlockPos &pos, unsigned int nAddSize); + +static bool WriteUndoDataForBlock(const CBlockUndo& blockundo, CValidationState& state, CBlockIndex* pindex, const CChainParams& chainparams) +{ + // Write undo information to disk + if (pindex->GetUndoPos().IsNull()) { + CDiskBlockPos _pos; + if (!FindUndoPos(state, pindex->nFile, _pos, ::GetSerializeSize(blockundo, SER_DISK, CLIENT_VERSION) + 40)) + return error("ConnectBlock(): FindUndoPos failed"); + if (!UndoWriteToDisk(blockundo, _pos, pindex->pprev->GetBlockHash(), chainparams.MessageStart())) + return AbortNode(state, "Failed to write undo data"); + + // update nUndoPos in block index + pindex->nUndoPos = _pos.nPos; + pindex->nStatus |= BLOCK_HAVE_UNDO; + setDirtyBlockIndex.insert(pindex); + } + + return true; +} + +static CCheckQueue<CScriptCheck> scriptcheckqueue(128); + +void ThreadScriptCheck() { + RenameThread("bitcoin-scriptch"); + scriptcheckqueue.Thread(); +} + +// Protected by cs_main +VersionBitsCache versionbitscache; + +int32_t ComputeBlockVersion(const CBlockIndex* pindexPrev, const Consensus::Params& params) +{ + LOCK(cs_main); + int32_t nVersion = VERSIONBITS_TOP_BITS; + + for (int i = 0; i < (int)Consensus::MAX_VERSION_BITS_DEPLOYMENTS; i++) { + ThresholdState state = VersionBitsState(pindexPrev, params, static_cast<Consensus::DeploymentPos>(i), versionbitscache); + if (state == ThresholdState::LOCKED_IN || state == ThresholdState::STARTED) { + nVersion |= VersionBitsMask(params, static_cast<Consensus::DeploymentPos>(i)); + } + } + + return nVersion; +} + +/** + * Threshold condition checker that triggers when unknown versionbits are seen on the network. + */ +class WarningBitsConditionChecker : public AbstractThresholdConditionChecker +{ +private: + int bit; + +public: + explicit WarningBitsConditionChecker(int bitIn) : bit(bitIn) {} + + int64_t BeginTime(const Consensus::Params& params) const override { return 0; } + int64_t EndTime(const Consensus::Params& params) const override { return std::numeric_limits<int64_t>::max(); } + int Period(const Consensus::Params& params) const override { return params.nMinerConfirmationWindow; } + int Threshold(const Consensus::Params& params) const override { return params.nRuleChangeActivationThreshold; } + + bool Condition(const CBlockIndex* pindex, const Consensus::Params& params) const override + { + return ((pindex->nVersion & VERSIONBITS_TOP_MASK) == VERSIONBITS_TOP_BITS) && + ((pindex->nVersion >> bit) & 1) != 0 && + ((ComputeBlockVersion(pindex->pprev, params) >> bit) & 1) == 0; + } +}; + +// Protected by cs_main +static ThresholdConditionCache warningcache[VERSIONBITS_NUM_BITS]; + +// 0.13.0 was shipped with a segwit deployment defined for testnet, but not for +// mainnet. We no longer need to support disabling the segwit deployment +// except for testing purposes, due to limitations of the functional test +// environment. See test/functional/p2p-segwit.py. +static bool IsScriptWitnessEnabled(const Consensus::Params& params) +{ + return params.vDeployments[Consensus::DEPLOYMENT_SEGWIT].nTimeout != 0; +} + +static unsigned int GetBlockScriptFlags(const CBlockIndex* pindex, const Consensus::Params& consensusparams) { + AssertLockHeld(cs_main); + + unsigned int flags = SCRIPT_VERIFY_NONE; + + // BIP16 didn't become active until Apr 1 2012 (on mainnet, and + // retroactively applied to testnet) + // However, only one historical block violated the P2SH rules (on both + // mainnet and testnet), so for simplicity, always leave P2SH + // on except for the one violating block. + if (consensusparams.BIP16Exception.IsNull() || // no bip16 exception on this chain + pindex->phashBlock == nullptr || // this is a new candidate block, eg from TestBlockValidity() + *pindex->phashBlock != consensusparams.BIP16Exception) // this block isn't the historical exception + { + flags |= SCRIPT_VERIFY_P2SH; + } + + // Enforce WITNESS rules whenever P2SH is in effect (and the segwit + // deployment is defined). + if (flags & SCRIPT_VERIFY_P2SH && IsScriptWitnessEnabled(consensusparams)) { + flags |= SCRIPT_VERIFY_WITNESS; + } + + // Start enforcing the DERSIG (BIP66) rule + if (pindex->nHeight >= consensusparams.BIP66Height) { + flags |= SCRIPT_VERIFY_DERSIG; + } + + // Start enforcing CHECKLOCKTIMEVERIFY (BIP65) rule + if (pindex->nHeight >= consensusparams.BIP65Height) { + flags |= SCRIPT_VERIFY_CHECKLOCKTIMEVERIFY; + } + + // Start enforcing BIP68 (sequence locks) and BIP112 (CHECKSEQUENCEVERIFY) using versionbits logic. + if (VersionBitsState(pindex->pprev, consensusparams, Consensus::DEPLOYMENT_CSV, versionbitscache) == ThresholdState::ACTIVE) { + flags |= SCRIPT_VERIFY_CHECKSEQUENCEVERIFY; + } + + if (IsNullDummyEnabled(pindex->pprev, consensusparams)) { + flags |= SCRIPT_VERIFY_NULLDUMMY; + } + + return flags; +} + + + +static int64_t nTimeCheck = 0; +static int64_t nTimeForks = 0; +static int64_t nTimeVerify = 0; +static int64_t nTimeConnect = 0; +static int64_t nTimeIndex = 0; +static int64_t nTimeCallbacks = 0; +static int64_t nTimeTotal = 0; +static int64_t nBlocksTotal = 0; + +/** Apply the effects of this block (with given index) on the UTXO set represented by coins. + * Validity checks that depend on the UTXO set are also done; ConnectBlock() + * can fail if those validity checks fail (among other reasons). */ +bool CChainState::ConnectBlock(const CBlock& block, CValidationState& state, CBlockIndex* pindex, + CCoinsViewCache& view, const CChainParams& chainparams, bool fJustCheck) +{ + AssertLockHeld(cs_main); + assert(pindex); + assert(*pindex->phashBlock == block.GetHash()); + int64_t nTimeStart = GetTimeMicros(); + + // Check it again in case a previous version let a bad block in + // NOTE: We don't currently (re-)invoke ContextualCheckBlock() or + // ContextualCheckBlockHeader() here. This means that if we add a new + // consensus rule that is enforced in one of those two functions, then we + // may have let in a block that violates the rule prior to updating the + // software, and we would NOT be enforcing the rule here. Fully solving + // upgrade from one software version to the next after a consensus rule + // change is potentially tricky and issue-specific (see RewindBlockIndex() + // for one general approach that was used for BIP 141 deployment). + // Also, currently the rule against blocks more than 2 hours in the future + // is enforced in ContextualCheckBlockHeader(); we wouldn't want to + // re-enforce that rule here (at least until we make it impossible for + // GetAdjustedTime() to go backward). + if (!CheckBlock(block, state, chainparams.GetConsensus(), !fJustCheck, !fJustCheck)) { + if (state.CorruptionPossible()) { + // We don't write down blocks to disk if they may have been + // corrupted, so this should be impossible unless we're having hardware + // problems. + return AbortNode(state, "Corrupt block found indicating potential hardware failure; shutting down"); + } + return error("%s: Consensus::CheckBlock: %s", __func__, FormatStateMessage(state)); + } + + // verify that the view's current state corresponds to the previous block + uint256 hashPrevBlock = pindex->pprev == nullptr ? uint256() : pindex->pprev->GetBlockHash(); + assert(hashPrevBlock == view.GetBestBlock()); + + // Special case for the genesis block, skipping connection of its transactions + // (its coinbase is unspendable) + if (block.GetHash() == chainparams.GetConsensus().hashGenesisBlock) { + if (!fJustCheck) + view.SetBestBlock(pindex->GetBlockHash()); + return true; + } + + nBlocksTotal++; + + bool fScriptChecks = true; + 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 >= nMinimumChainWork) { + // This block is a member of the assumed verified chain and an ancestor of the best header. + // The equivalent time check discourages hash power 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); + } + } + } + + int64_t nTime1 = GetTimeMicros(); nTimeCheck += nTime1 - nTimeStart; + LogPrint(BCLog::BENCH, " - Sanity checks: %.2fms [%.2fs (%.2fms/blk)]\n", MILLI * (nTime1 - nTimeStart), nTimeCheck * MICRO, nTimeCheck * MILLI / nBlocksTotal); + + // Do not allow blocks that contain transactions which 'overwrite' older transactions, + // unless those are already completely spent. + // If such overwrites are allowed, coinbases and transactions depending upon those + // can be duplicated to remove the ability to spend the first instance -- even after + // being sent to another address. + // See BIP30 and http://r6.ca/blog/20120206T005236Z.html for more information. + // This logic is not necessary for memory pool transactions, as AcceptToMemoryPool + // already refuses previously-known transaction ids entirely. + // This rule was originally applied to all blocks with a timestamp after March 15, 2012, 0:00 UTC. + // Now that the whole chain is irreversibly beyond that time it is applied to all blocks except the + // two in the chain that violate it. This prevents exploiting the issue against nodes during their + // initial block download. + bool fEnforceBIP30 = !((pindex->nHeight==91842 && pindex->GetBlockHash() == uint256S("0x00000000000a4d0a398161ffc163c503763b1f4360639393e0e4c8e300e0caec")) || + (pindex->nHeight==91880 && pindex->GetBlockHash() == uint256S("0x00000000000743f190a18c5577a3c2d2a1f610ae9601ac046a38084ccb7cd721"))); + + // Once BIP34 activated it was not possible to create new duplicate coinbases and thus other than starting + // with the 2 existing duplicate coinbase pairs, not possible to create overwriting txs. But by the + // time BIP34 activated, in each of the existing pairs the duplicate coinbase had overwritten the first + // before the first had been spent. Since those coinbases are sufficiently buried it's no longer possible to create further + // duplicate transactions descending from the known pairs either. + // If we're on the known chain at height greater than where BIP34 activated, we can save the db accesses needed for the BIP30 check. + + // BIP34 requires that a block at height X (block X) has its coinbase + // scriptSig start with a CScriptNum of X (indicated height X). The above + // logic of no longer requiring BIP30 once BIP34 activates is flawed in the + // case that there is a block X before the BIP34 height of 227,931 which has + // an indicated height Y where Y is greater than X. The coinbase for block + // X would also be a valid coinbase for block Y, which could be a BIP30 + // violation. An exhaustive search of all mainnet coinbases before the + // BIP34 height which have an indicated height greater than the block height + // reveals many occurrences. The 3 lowest indicated heights found are + // 209,921, 490,897, and 1,983,702 and thus coinbases for blocks at these 3 + // heights would be the first opportunity for BIP30 to be violated. + + // The search reveals a great many blocks which have an indicated height + // greater than 1,983,702, so we simply remove the optimization to skip + // BIP30 checking for blocks at height 1,983,702 or higher. Before we reach + // that block in another 25 years or so, we should take advantage of a + // future consensus change to do a new and improved version of BIP34 that + // will actually prevent ever creating any duplicate coinbases in the + // future. + static constexpr int BIP34_IMPLIES_BIP30_LIMIT = 1983702; + + // There is no potential to create a duplicate coinbase at block 209,921 + // because this is still before the BIP34 height and so explicit BIP30 + // checking is still active. + + // The final case is block 176,684 which has an indicated height of + // 490,897. Unfortunately, this issue was not discovered until about 2 weeks + // before block 490,897 so there was not much opportunity to address this + // case other than to carefully analyze it and determine it would not be a + // problem. Block 490,897 was, in fact, mined with a different coinbase than + // block 176,684, but it is important to note that even if it hadn't been or + // is remined on an alternate fork with a duplicate coinbase, we would still + // not run into a BIP30 violation. This is because the coinbase for 176,684 + // is spent in block 185,956 in transaction + // d4f7fbbf92f4a3014a230b2dc70b8058d02eb36ac06b4a0736d9d60eaa9e8781. This + // spending transaction can't be duplicated because it also spends coinbase + // 0328dd85c331237f18e781d692c92de57649529bd5edf1d01036daea32ffde29. This + // coinbase has an indicated height of over 4.2 billion, and wouldn't be + // duplicatable until that height, and it's currently impossible to create a + // chain that long. Nevertheless we may wish to consider a future soft fork + // which retroactively prevents block 490,897 from creating a duplicate + // coinbase. The two historical BIP30 violations often provide a confusing + // edge case when manipulating the UTXO and it would be simpler not to have + // another edge case to deal with. + + // testnet3 has no blocks before the BIP34 height with indicated heights + // post BIP34 before approximately height 486,000,000 and presumably will + // be reset before it reaches block 1,983,702 and starts doing unnecessary + // BIP30 checking again. + assert(pindex->pprev); + CBlockIndex *pindexBIP34height = pindex->pprev->GetAncestor(chainparams.GetConsensus().BIP34Height); + //Only continue to enforce if we're below BIP34 activation height or the block hash at that height doesn't correspond. + fEnforceBIP30 = fEnforceBIP30 && (!pindexBIP34height || !(pindexBIP34height->GetBlockHash() == chainparams.GetConsensus().BIP34Hash)); + + // TODO: Remove BIP30 checking from block height 1,983,702 on, once we have a + // consensus change that ensures coinbases at those heights can not + // duplicate earlier coinbases. + if (fEnforceBIP30 || pindex->nHeight >= BIP34_IMPLIES_BIP30_LIMIT) { + for (const auto& tx : block.vtx) { + for (size_t o = 0; o < tx->vout.size(); o++) { + if (view.HaveCoin(COutPoint(tx->GetHash(), o))) { + return state.DoS(100, error("ConnectBlock(): tried to overwrite transaction"), + REJECT_INVALID, "bad-txns-BIP30"); + } + } + } + } + + // Start enforcing BIP68 (sequence locks) and BIP112 (CHECKSEQUENCEVERIFY) using versionbits logic. + int nLockTimeFlags = 0; + if (VersionBitsState(pindex->pprev, chainparams.GetConsensus(), Consensus::DEPLOYMENT_CSV, versionbitscache) == ThresholdState::ACTIVE) { + nLockTimeFlags |= LOCKTIME_VERIFY_SEQUENCE; + } + + // Get the script flags for this block + unsigned int flags = GetBlockScriptFlags(pindex, chainparams.GetConsensus()); + + int64_t nTime2 = GetTimeMicros(); nTimeForks += nTime2 - nTime1; + LogPrint(BCLog::BENCH, " - Fork checks: %.2fms [%.2fs (%.2fms/blk)]\n", MILLI * (nTime2 - nTime1), nTimeForks * MICRO, nTimeForks * MILLI / nBlocksTotal); + + CBlockUndo blockundo; + + CCheckQueueControl<CScriptCheck> control(fScriptChecks && nScriptCheckThreads ? &scriptcheckqueue : nullptr); + + std::vector<int> prevheights; + CAmount nFees = 0; + int nInputs = 0; + int64_t nSigOpsCost = 0; + blockundo.vtxundo.reserve(block.vtx.size() - 1); + std::vector<PrecomputedTransactionData> 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]); + + nInputs += tx.vin.size(); + + if (!tx.IsCoinBase()) + { + CAmount txfee = 0; + if (!Consensus::CheckTxInputs(tx, state, view, pindex->nHeight, txfee)) { + return error("%s: Consensus::CheckTxInputs: %s, %s", __func__, tx.GetHash().ToString(), FormatStateMessage(state)); + } + nFees += txfee; + if (!MoneyRange(nFees)) { + return state.DoS(100, error("%s: accumulated fee in the block out of range.", __func__), + REJECT_INVALID, "bad-txns-accumulated-fee-outofrange"); + } + + // Check that transaction is BIP68 final + // BIP68 lock checks (as opposed to nLockTime checks) must + // be in ConnectBlock because they require the UTXO set + prevheights.resize(tx.vin.size()); + for (size_t j = 0; j < tx.vin.size(); j++) { + prevheights[j] = view.AccessCoin(tx.vin[j].prevout).nHeight; + } + + if (!SequenceLocks(tx, nLockTimeFlags, &prevheights, *pindex)) { + return state.DoS(100, error("%s: contains a non-BIP68-final transaction", __func__), + REJECT_INVALID, "bad-txns-nonfinal"); + } + } + + // GetTransactionSigOpCost counts 3 types of sigops: + // * legacy (always) + // * p2sh (when P2SH enabled in flags and excludes coinbase) + // * witness (when witness enabled in flags and excludes coinbase) + nSigOpsCost += GetTransactionSigOpCost(tx, view, flags); + if (nSigOpsCost > MAX_BLOCK_SIGOPS_COST) + return state.DoS(100, error("ConnectBlock(): too many sigops"), + REJECT_INVALID, "bad-blk-sigops"); + + txdata.emplace_back(tx); + if (!tx.IsCoinBase()) + { + 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, fCacheResults, txdata[i], nScriptCheckThreads ? &vChecks : nullptr)) + return error("ConnectBlock(): CheckInputs on %s failed with %s", + tx.GetHash().ToString(), FormatStateMessage(state)); + control.Add(vChecks); + } + + CTxUndo undoDummy; + if (i > 0) { + blockundo.vtxundo.push_back(CTxUndo()); + } + UpdateCoins(tx, view, i == 0 ? undoDummy : blockundo.vtxundo.back(), pindex->nHeight); + } + int64_t nTime3 = GetTimeMicros(); nTimeConnect += nTime3 - nTime2; + LogPrint(BCLog::BENCH, " - Connect %u transactions: %.2fms (%.3fms/tx, %.3fms/txin) [%.2fs (%.2fms/blk)]\n", (unsigned)block.vtx.size(), MILLI * (nTime3 - nTime2), MILLI * (nTime3 - nTime2) / block.vtx.size(), nInputs <= 1 ? 0 : MILLI * (nTime3 - nTime2) / (nInputs-1), nTimeConnect * MICRO, nTimeConnect * MILLI / nBlocksTotal); + + CAmount blockReward = nFees + GetBlockSubsidy(pindex->nHeight, chainparams.GetConsensus()); + if (block.vtx[0]->GetValueOut() > blockReward) + return state.DoS(100, + error("ConnectBlock(): coinbase pays too much (actual=%d vs limit=%d)", + block.vtx[0]->GetValueOut(), blockReward), + REJECT_INVALID, "bad-cb-amount"); + + if (!control.Wait()) + return state.DoS(100, error("%s: CheckQueue failed", __func__), REJECT_INVALID, "block-validation-failed"); + int64_t nTime4 = GetTimeMicros(); nTimeVerify += nTime4 - nTime2; + LogPrint(BCLog::BENCH, " - Verify %u txins: %.2fms (%.3fms/txin) [%.2fs (%.2fms/blk)]\n", nInputs - 1, MILLI * (nTime4 - nTime2), nInputs <= 1 ? 0 : MILLI * (nTime4 - nTime2) / (nInputs-1), nTimeVerify * MICRO, nTimeVerify * MILLI / nBlocksTotal); + + if (fJustCheck) + return true; + + if (!WriteUndoDataForBlock(blockundo, state, pindex, chainparams)) + return false; + + if (!pindex->IsValid(BLOCK_VALID_SCRIPTS)) { + pindex->RaiseValidity(BLOCK_VALID_SCRIPTS); + setDirtyBlockIndex.insert(pindex); + } + + assert(pindex->phashBlock); + // add this block to the view's block chain + view.SetBestBlock(pindex->GetBlockHash()); + + int64_t nTime5 = GetTimeMicros(); nTimeIndex += nTime5 - nTime4; + LogPrint(BCLog::BENCH, " - Index writing: %.2fms [%.2fs (%.2fms/blk)]\n", MILLI * (nTime5 - nTime4), nTimeIndex * MICRO, nTimeIndex * MILLI / nBlocksTotal); + + int64_t nTime6 = GetTimeMicros(); nTimeCallbacks += nTime6 - nTime5; + LogPrint(BCLog::BENCH, " - Callbacks: %.2fms [%.2fs (%.2fms/blk)]\n", MILLI * (nTime6 - nTime5), nTimeCallbacks * MICRO, nTimeCallbacks * MILLI / nBlocksTotal); + + return true; +} + +/** + * Update the on-disk chain state. + * The caches and indexes are flushed depending on the mode we're called with + * if they're too large, if it's been a while since the last write, + * or always and in all cases if we're in prune mode and are deleting files. + * + * If FlushStateMode::NONE is used, then FlushStateToDisk(...) won't do anything + * besides checking if we need to prune. + */ +bool static FlushStateToDisk(const CChainParams& chainparams, CValidationState &state, FlushStateMode mode, int nManualPruneHeight) { + int64_t nMempoolUsage = mempool.DynamicMemoryUsage(); + LOCK(cs_main); + static int64_t nLastWrite = 0; + static int64_t nLastFlush = 0; + std::set<int> setFilesToPrune; + bool full_flush_completed = false; + try { + { + bool fFlushForPrune = false; + bool fDoFullFlush = false; + LOCK(cs_LastBlockFile); + if (fPruneMode && (fCheckForPruning || nManualPruneHeight > 0) && !fReindex) { + if (nManualPruneHeight > 0) { + FindFilesToPruneManual(setFilesToPrune, nManualPruneHeight); + } else { + FindFilesToPrune(setFilesToPrune, chainparams.PruneAfterHeight()); + fCheckForPruning = false; + } + if (!setFilesToPrune.empty()) { + fFlushForPrune = true; + if (!fHavePruned) { + pblocktree->WriteFlag("prunedblockfiles", true); + fHavePruned = true; + } + } + } + int64_t nNow = GetTimeMicros(); + // Avoid writing/flushing immediately after startup. + if (nLastWrite == 0) { + nLastWrite = nNow; + } + if (nLastFlush == 0) { + nLastFlush = nNow; + } + int64_t nMempoolSizeMax = gArgs.GetArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) * 1000000; + int64_t cacheSize = pcoinsTip->DynamicMemoryUsage(); + int64_t nTotalSpace = nCoinCacheUsage + std::max<int64_t>(nMempoolSizeMax - nMempoolUsage, 0); + // The cache is large and we're within 10% and 10 MiB of the limit, but we have time now (not in the middle of a block processing). + bool fCacheLarge = mode == FlushStateMode::PERIODIC && cacheSize > std::max((9 * nTotalSpace) / 10, nTotalSpace - MAX_BLOCK_COINSDB_USAGE * 1024 * 1024); + // The cache is over the limit, we have to write now. + bool fCacheCritical = mode == FlushStateMode::IF_NEEDED && cacheSize > nTotalSpace; + // It's been a while since we wrote the block index to disk. Do this frequently, so we don't need to redownload after a crash. + bool fPeriodicWrite = mode == FlushStateMode::PERIODIC && nNow > nLastWrite + (int64_t)DATABASE_WRITE_INTERVAL * 1000000; + // It's been very long since we flushed the cache. Do this infrequently, to optimize cache usage. + bool fPeriodicFlush = mode == FlushStateMode::PERIODIC && nNow > nLastFlush + (int64_t)DATABASE_FLUSH_INTERVAL * 1000000; + // Combine all conditions that result in a full cache flush. + fDoFullFlush = (mode == FlushStateMode::ALWAYS) || fCacheLarge || fCacheCritical || fPeriodicFlush || fFlushForPrune; + // Write blocks and block index to disk. + if (fDoFullFlush || fPeriodicWrite) { + // Depend on nMinDiskSpace to ensure we can write block index + if (!CheckDiskSpace(0, true)) + return state.Error("out of disk space"); + // First make sure all block and undo data is flushed to disk. + FlushBlockFile(); + // Then update all block file information (which may refer to block and undo files). + { + std::vector<std::pair<int, const CBlockFileInfo*> > vFiles; + vFiles.reserve(setDirtyFileInfo.size()); + for (std::set<int>::iterator it = setDirtyFileInfo.begin(); it != setDirtyFileInfo.end(); ) { + vFiles.push_back(std::make_pair(*it, &vinfoBlockFile[*it])); + setDirtyFileInfo.erase(it++); + } + std::vector<const CBlockIndex*> vBlocks; + vBlocks.reserve(setDirtyBlockIndex.size()); + for (std::set<CBlockIndex*>::iterator it = setDirtyBlockIndex.begin(); it != setDirtyBlockIndex.end(); ) { + vBlocks.push_back(*it); + setDirtyBlockIndex.erase(it++); + } + if (!pblocktree->WriteBatchSync(vFiles, nLastBlockFile, vBlocks)) { + return AbortNode(state, "Failed to write to block index database"); + } + } + // Finally remove any pruned files + if (fFlushForPrune) + UnlinkPrunedFiles(setFilesToPrune); + nLastWrite = nNow; + } + // Flush best chain related state. This can only be done if the blocks / block index write was also done. + if (fDoFullFlush && !pcoinsTip->GetBestBlock().IsNull()) { + // Typical Coin structures on disk are around 48 bytes in size. + // Pushing a new one to the database can cause it to be written + // twice (once in the log, and once in the tables). This is already + // an overestimation, as most will delete an existing entry or + // overwrite one. Still, use a conservative safety factor of 2. + if (!CheckDiskSpace(48 * 2 * 2 * pcoinsTip->GetCacheSize())) + return state.Error("out of disk space"); + // Flush the chainstate (which may refer to block index entries). + if (!pcoinsTip->Flush()) + return AbortNode(state, "Failed to write to coin database"); + nLastFlush = nNow; + full_flush_completed = true; + } + } + if (full_flush_completed) { + // Update best block in wallet (so we can detect restored wallets). + GetMainSignals().ChainStateFlushed(chainActive.GetLocator()); + } + } catch (const std::runtime_error& e) { + return AbortNode(state, std::string("System error while flushing: ") + e.what()); + } + return true; +} + +void FlushStateToDisk() { + CValidationState state; + const CChainParams& chainparams = Params(); + if (!FlushStateToDisk(chainparams, state, FlushStateMode::ALWAYS)) { + LogPrintf("%s: failed to flush state (%s)\n", __func__, FormatStateMessage(state)); + } +} + +void PruneAndFlush() { + CValidationState state; + fCheckForPruning = true; + const CChainParams& chainparams = Params(); + if (!FlushStateToDisk(chainparams, state, FlushStateMode::NONE)) { + LogPrintf("%s: failed to flush state (%s)\n", __func__, FormatStateMessage(state)); + } +} + +static void DoWarning(const std::string& strWarning) +{ + static bool fWarned = false; + SetMiscWarning(strWarning); + if (!fWarned) { + AlertNotify(strWarning); + fWarned = true; + } +} + +/** Private helper function that concatenates warning messages. */ +static void AppendWarning(std::string& res, const std::string& warn) +{ + if (!res.empty()) res += ", "; + res += warn; +} + +/** Check warning conditions and do some notifications on new chain tip set. */ +void static UpdateTip(const CBlockIndex *pindexNew, const CChainParams& chainParams) { + // New best block + mempool.AddTransactionsUpdated(1); + + { + WaitableLock lock(g_best_block_mutex); + g_best_block = pindexNew->GetBlockHash(); + g_best_block_cv.notify_all(); + } + + std::string warningMessages; + if (!IsInitialBlockDownload()) + { + int nUpgraded = 0; + const CBlockIndex* pindex = pindexNew; + for (int bit = 0; bit < VERSIONBITS_NUM_BITS; bit++) { + WarningBitsConditionChecker checker(bit); + ThresholdState state = checker.GetStateFor(pindex, chainParams.GetConsensus(), warningcache[bit]); + if (state == ThresholdState::ACTIVE || state == ThresholdState::LOCKED_IN) { + const std::string strWarning = strprintf(_("Warning: unknown new rules activated (versionbit %i)"), bit); + if (state == ThresholdState::ACTIVE) { + DoWarning(strWarning); + } else { + AppendWarning(warningMessages, strWarning); + } + } + } + // Check the version of the last 100 blocks to see if we need to upgrade: + for (int i = 0; i < 100 && pindex != nullptr; i++) + { + int32_t nExpectedVersion = ComputeBlockVersion(pindex->pprev, chainParams.GetConsensus()); + if (pindex->nVersion > VERSIONBITS_LAST_OLD_BLOCK_VERSION && (pindex->nVersion & ~nExpectedVersion) != 0) + ++nUpgraded; + pindex = pindex->pprev; + } + if (nUpgraded > 0) + AppendWarning(warningMessages, strprintf(_("%d of last 100 blocks have unexpected version"), nUpgraded)); + if (nUpgraded > 100/2) + { + std::string strWarning = _("Warning: Unknown block versions being mined! It's possible unknown rules are in effect"); + // notify GetWarnings(), called by Qt and the JSON-RPC code to warn the user: + DoWarning(strWarning); + } + } + LogPrintf("%s: new best=%s height=%d version=0x%08x log2_work=%.8g tx=%lu date='%s' progress=%f cache=%.1fMiB(%utxo)", __func__, /* Continued */ + pindexNew->GetBlockHash().ToString(), pindexNew->nHeight, pindexNew->nVersion, + log(pindexNew->nChainWork.getdouble())/log(2.0), (unsigned long)pindexNew->nChainTx, + FormatISO8601DateTime(pindexNew->GetBlockTime()), + GuessVerificationProgress(chainParams.TxData(), pindexNew), pcoinsTip->DynamicMemoryUsage() * (1.0 / (1<<20)), pcoinsTip->GetCacheSize()); + if (!warningMessages.empty()) + LogPrintf(" warning='%s'", warningMessages); /* Continued */ + LogPrintf("\n"); + +} + +/** Disconnect chainActive's tip. + * After calling, the mempool will be in an inconsistent state, with + * transactions from disconnected blocks being added to disconnectpool. You + * should make the mempool consistent again by calling UpdateMempoolForReorg. + * with cs_main held. + * + * If disconnectpool is nullptr, then no disconnected transactions are added to + * disconnectpool (note that the caller is responsible for mempool consistency + * in any case). + */ +bool CChainState::DisconnectTip(CValidationState& state, const CChainParams& chainparams, DisconnectedBlockTransactions *disconnectpool) +{ + CBlockIndex *pindexDelete = chainActive.Tip(); + assert(pindexDelete); + // Read block from disk. + std::shared_ptr<CBlock> pblock = std::make_shared<CBlock>(); + CBlock& block = *pblock; + if (!ReadBlockFromDisk(block, pindexDelete, chainparams.GetConsensus())) + return AbortNode(state, "Failed to read block"); + // Apply the block atomically to the chain state. + int64_t nStart = GetTimeMicros(); + { + CCoinsViewCache view(pcoinsTip.get()); + assert(view.GetBestBlock() == pindexDelete->GetBlockHash()); + if (DisconnectBlock(block, pindexDelete, view) != DISCONNECT_OK) + return error("DisconnectTip(): DisconnectBlock %s failed", pindexDelete->GetBlockHash().ToString()); + bool flushed = view.Flush(); + assert(flushed); + } + LogPrint(BCLog::BENCH, "- Disconnect block: %.2fms\n", (GetTimeMicros() - nStart) * MILLI); + // Write the chain state to disk, if necessary. + if (!FlushStateToDisk(chainparams, state, FlushStateMode::IF_NEEDED)) + return false; + + if (disconnectpool) { + // Save transactions to re-add to mempool at end of reorg + for (auto it = block.vtx.rbegin(); it != block.vtx.rend(); ++it) { + disconnectpool->addTransaction(*it); + } + while (disconnectpool->DynamicMemoryUsage() > MAX_DISCONNECTED_TX_POOL_SIZE * 1000) { + // Drop the earliest entry, and remove its children from the mempool. + auto it = disconnectpool->queuedTx.get<insertion_order>().begin(); + mempool.removeRecursive(**it, MemPoolRemovalReason::REORG); + disconnectpool->removeEntry(it); + } + } + + chainActive.SetTip(pindexDelete->pprev); + + UpdateTip(pindexDelete->pprev, chainparams); + // Let wallets know transactions went from 1-confirmed to + // 0-confirmed or conflicted: + GetMainSignals().BlockDisconnected(pblock); + return true; +} + +static int64_t nTimeReadFromDisk = 0; +static int64_t nTimeConnectTotal = 0; +static int64_t nTimeFlush = 0; +static int64_t nTimeChainState = 0; +static int64_t nTimePostConnect = 0; + +struct PerBlockConnectTrace { + CBlockIndex* pindex = nullptr; + std::shared_ptr<const CBlock> pblock; + std::shared_ptr<std::vector<CTransactionRef>> conflictedTxs; + PerBlockConnectTrace() : conflictedTxs(std::make_shared<std::vector<CTransactionRef>>()) {} +}; +/** + * Used to track blocks whose transactions were applied to the UTXO state as a + * part of a single ActivateBestChainStep call. + * + * This class also tracks transactions that are removed from the mempool as + * conflicts (per block) and can be used to pass all those transactions + * through SyncTransaction. + * + * This class assumes (and asserts) that the conflicted transactions for a given + * block are added via mempool callbacks prior to the BlockConnected() associated + * with those transactions. If any transactions are marked conflicted, it is + * assumed that an associated block will always be added. + * + * This class is single-use, once you call GetBlocksConnected() you have to throw + * it away and make a new one. + */ +class ConnectTrace { +private: + std::vector<PerBlockConnectTrace> blocksConnected; + CTxMemPool &pool; + +public: + explicit ConnectTrace(CTxMemPool &_pool) : blocksConnected(1), pool(_pool) { + pool.NotifyEntryRemoved.connect(boost::bind(&ConnectTrace::NotifyEntryRemoved, this, _1, _2)); + } + + ~ConnectTrace() { + pool.NotifyEntryRemoved.disconnect(boost::bind(&ConnectTrace::NotifyEntryRemoved, this, _1, _2)); + } + + void BlockConnected(CBlockIndex* pindex, std::shared_ptr<const CBlock> pblock) { + assert(!blocksConnected.back().pindex); + assert(pindex); + assert(pblock); + blocksConnected.back().pindex = pindex; + blocksConnected.back().pblock = std::move(pblock); + blocksConnected.emplace_back(); + } + + std::vector<PerBlockConnectTrace>& GetBlocksConnected() { + // We always keep one extra block at the end of our list because + // blocks are added after all the conflicted transactions have + // been filled in. Thus, the last entry should always be an empty + // one waiting for the transactions from the next block. We pop + // the last entry here to make sure the list we return is sane. + assert(!blocksConnected.back().pindex); + assert(blocksConnected.back().conflictedTxs->empty()); + blocksConnected.pop_back(); + return blocksConnected; + } + + void NotifyEntryRemoved(CTransactionRef txRemoved, MemPoolRemovalReason reason) { + assert(!blocksConnected.back().pindex); + if (reason == MemPoolRemovalReason::CONFLICT) { + blocksConnected.back().conflictedTxs->emplace_back(std::move(txRemoved)); + } + } +}; + +/** + * Connect a new block to chainActive. pblock is either nullptr or a pointer to a CBlock + * corresponding to pindexNew, to bypass loading it again from disk. + * + * The block is added to connectTrace if connection succeeds. + */ +bool CChainState::ConnectTip(CValidationState& state, const CChainParams& chainparams, CBlockIndex* pindexNew, const std::shared_ptr<const CBlock>& pblock, ConnectTrace& connectTrace, DisconnectedBlockTransactions &disconnectpool) +{ + assert(pindexNew->pprev == chainActive.Tip()); + // Read block from disk. + int64_t nTime1 = GetTimeMicros(); + std::shared_ptr<const CBlock> pthisBlock; + if (!pblock) { + std::shared_ptr<CBlock> pblockNew = std::make_shared<CBlock>(); + if (!ReadBlockFromDisk(*pblockNew, pindexNew, chainparams.GetConsensus())) + return AbortNode(state, "Failed to read block"); + pthisBlock = pblockNew; + } else { + pthisBlock = pblock; + } + const CBlock& blockConnecting = *pthisBlock; + // Apply the block atomically to the chain state. + int64_t nTime2 = GetTimeMicros(); nTimeReadFromDisk += nTime2 - nTime1; + int64_t nTime3; + LogPrint(BCLog::BENCH, " - Load block from disk: %.2fms [%.2fs]\n", (nTime2 - nTime1) * MILLI, nTimeReadFromDisk * MICRO); + { + CCoinsViewCache view(pcoinsTip.get()); + bool rv = ConnectBlock(blockConnecting, state, pindexNew, view, chainparams); + GetMainSignals().BlockChecked(blockConnecting, state); + if (!rv) { + if (state.IsInvalid()) + InvalidBlockFound(pindexNew, state); + return error("ConnectTip(): ConnectBlock %s failed", pindexNew->GetBlockHash().ToString()); + } + nTime3 = GetTimeMicros(); nTimeConnectTotal += nTime3 - nTime2; + LogPrint(BCLog::BENCH, " - Connect total: %.2fms [%.2fs (%.2fms/blk)]\n", (nTime3 - nTime2) * MILLI, nTimeConnectTotal * MICRO, nTimeConnectTotal * MILLI / nBlocksTotal); + bool flushed = view.Flush(); + assert(flushed); + } + int64_t nTime4 = GetTimeMicros(); nTimeFlush += nTime4 - nTime3; + LogPrint(BCLog::BENCH, " - Flush: %.2fms [%.2fs (%.2fms/blk)]\n", (nTime4 - nTime3) * MILLI, nTimeFlush * MICRO, nTimeFlush * MILLI / nBlocksTotal); + // Write the chain state to disk, if necessary. + if (!FlushStateToDisk(chainparams, state, FlushStateMode::IF_NEEDED)) + return false; + int64_t nTime5 = GetTimeMicros(); nTimeChainState += nTime5 - nTime4; + LogPrint(BCLog::BENCH, " - Writing chainstate: %.2fms [%.2fs (%.2fms/blk)]\n", (nTime5 - nTime4) * MILLI, nTimeChainState * MICRO, nTimeChainState * MILLI / nBlocksTotal); + // Remove conflicting transactions from the mempool.; + mempool.removeForBlock(blockConnecting.vtx, pindexNew->nHeight); + disconnectpool.removeForBlock(blockConnecting.vtx); + // Update chainActive & related variables. + chainActive.SetTip(pindexNew); + UpdateTip(pindexNew, chainparams); + + int64_t nTime6 = GetTimeMicros(); nTimePostConnect += nTime6 - nTime5; nTimeTotal += nTime6 - nTime1; + LogPrint(BCLog::BENCH, " - Connect postprocess: %.2fms [%.2fs (%.2fms/blk)]\n", (nTime6 - nTime5) * MILLI, nTimePostConnect * MICRO, nTimePostConnect * MILLI / nBlocksTotal); + LogPrint(BCLog::BENCH, "- Connect block: %.2fms [%.2fs (%.2fms/blk)]\n", (nTime6 - nTime1) * MILLI, nTimeTotal * MICRO, nTimeTotal * MILLI / nBlocksTotal); + + connectTrace.BlockConnected(pindexNew, std::move(pthisBlock)); + return true; +} + +/** + * Return the tip of the chain with the most work in it, that isn't + * known to be invalid (it's however far from certain to be valid). + */ +CBlockIndex* CChainState::FindMostWorkChain() { + do { + CBlockIndex *pindexNew = nullptr; + + // Find the best candidate header. + { + std::set<CBlockIndex*, CBlockIndexWorkComparator>::reverse_iterator it = setBlockIndexCandidates.rbegin(); + if (it == setBlockIndexCandidates.rend()) + return nullptr; + pindexNew = *it; + } + + // Check whether all blocks on the path between the currently active chain and the candidate are valid. + // Just going until the active chain is an optimization, as we know all blocks in it are valid already. + CBlockIndex *pindexTest = pindexNew; + bool fInvalidAncestor = false; + while (pindexTest && !chainActive.Contains(pindexTest)) { + assert(pindexTest->nChainTx || pindexTest->nHeight == 0); + + // Pruned nodes may have entries in setBlockIndexCandidates for + // which block files have been deleted. Remove those as candidates + // for the most work chain if we come across them; we can't switch + // to a chain unless we have all the non-active-chain parent blocks. + bool fFailedChain = pindexTest->nStatus & BLOCK_FAILED_MASK; + bool fMissingData = !(pindexTest->nStatus & BLOCK_HAVE_DATA); + if (fFailedChain || fMissingData) { + // Candidate chain is not usable (either invalid or missing data) + if (fFailedChain && (pindexBestInvalid == nullptr || pindexNew->nChainWork > pindexBestInvalid->nChainWork)) + pindexBestInvalid = pindexNew; + CBlockIndex *pindexFailed = pindexNew; + // Remove the entire chain from the set. + while (pindexTest != pindexFailed) { + if (fFailedChain) { + pindexFailed->nStatus |= BLOCK_FAILED_CHILD; + } else if (fMissingData) { + // If we're missing data, then add back to mapBlocksUnlinked, + // so that if the block arrives in the future we can try adding + // to setBlockIndexCandidates again. + mapBlocksUnlinked.insert(std::make_pair(pindexFailed->pprev, pindexFailed)); + } + setBlockIndexCandidates.erase(pindexFailed); + pindexFailed = pindexFailed->pprev; + } + setBlockIndexCandidates.erase(pindexTest); + fInvalidAncestor = true; + break; + } + pindexTest = pindexTest->pprev; + } + if (!fInvalidAncestor) + return pindexNew; + } while(true); +} + +/** Delete all entries in setBlockIndexCandidates that are worse than the current tip. */ +void CChainState::PruneBlockIndexCandidates() { + // Note that we can't delete the current block itself, as we may need to return to it later in case a + // reorganization to a better block fails. + std::set<CBlockIndex*, CBlockIndexWorkComparator>::iterator it = setBlockIndexCandidates.begin(); + while (it != setBlockIndexCandidates.end() && setBlockIndexCandidates.value_comp()(*it, chainActive.Tip())) { + setBlockIndexCandidates.erase(it++); + } + // Either the current tip or a successor of it we're working towards is left in setBlockIndexCandidates. + assert(!setBlockIndexCandidates.empty()); +} + +/** + * Try to make some progress towards making pindexMostWork the active block. + * pblock is either nullptr or a pointer to a CBlock corresponding to pindexMostWork. + */ +bool CChainState::ActivateBestChainStep(CValidationState& state, const CChainParams& chainparams, CBlockIndex* pindexMostWork, const std::shared_ptr<const CBlock>& pblock, bool& fInvalidFound, ConnectTrace& connectTrace) +{ + AssertLockHeld(cs_main); + + const CBlockIndex *pindexOldTip = chainActive.Tip(); + const CBlockIndex *pindexFork = chainActive.FindFork(pindexMostWork); + + // Disconnect active blocks which are no longer in the best chain. + bool fBlocksDisconnected = false; + DisconnectedBlockTransactions disconnectpool; + while (chainActive.Tip() && chainActive.Tip() != pindexFork) { + if (!DisconnectTip(state, chainparams, &disconnectpool)) { + // This is likely a fatal error, but keep the mempool consistent, + // just in case. Only remove from the mempool in this case. + UpdateMempoolForReorg(disconnectpool, false); + return false; + } + fBlocksDisconnected = true; + } + + // Build list of new blocks to connect. + std::vector<CBlockIndex*> vpindexToConnect; + bool fContinue = true; + int nHeight = pindexFork ? pindexFork->nHeight : -1; + while (fContinue && nHeight != pindexMostWork->nHeight) { + // Don't iterate the entire list of potential improvements toward the best tip, as we likely only need + // a few blocks along the way. + int nTargetHeight = std::min(nHeight + 32, pindexMostWork->nHeight); + vpindexToConnect.clear(); + vpindexToConnect.reserve(nTargetHeight - nHeight); + CBlockIndex *pindexIter = pindexMostWork->GetAncestor(nTargetHeight); + while (pindexIter && pindexIter->nHeight != nHeight) { + vpindexToConnect.push_back(pindexIter); + pindexIter = pindexIter->pprev; + } + nHeight = nTargetHeight; + + // Connect new blocks. + for (CBlockIndex *pindexConnect : reverse_iterate(vpindexToConnect)) { + if (!ConnectTip(state, chainparams, pindexConnect, pindexConnect == pindexMostWork ? pblock : std::shared_ptr<const CBlock>(), connectTrace, disconnectpool)) { + if (state.IsInvalid()) { + // The block violates a consensus rule. + if (!state.CorruptionPossible()) { + InvalidChainFound(vpindexToConnect.front()); + } + state = CValidationState(); + fInvalidFound = true; + fContinue = false; + break; + } else { + // A system error occurred (disk space, database error, ...). + // Make the mempool consistent with the current tip, just in case + // any observers try to use it before shutdown. + UpdateMempoolForReorg(disconnectpool, false); + return false; + } + } else { + PruneBlockIndexCandidates(); + if (!pindexOldTip || chainActive.Tip()->nChainWork > pindexOldTip->nChainWork) { + // We're in a better position than we were. Return temporarily to release the lock. + fContinue = false; + break; + } + } + } + } + + if (fBlocksDisconnected) { + // If any blocks were disconnected, disconnectpool may be non empty. Add + // any disconnected transactions back to the mempool. + UpdateMempoolForReorg(disconnectpool, true); + } + mempool.check(pcoinsTip.get()); + + // Callbacks/notifications for a new best chain. + if (fInvalidFound) + CheckForkWarningConditionsOnNewFork(vpindexToConnect.back()); + else + CheckForkWarningConditions(); + + return true; +} + +static void NotifyHeaderTip() LOCKS_EXCLUDED(cs_main) { + bool fNotify = false; + bool fInitialBlockDownload = false; + static CBlockIndex* pindexHeaderOld = nullptr; + CBlockIndex* pindexHeader = nullptr; + { + LOCK(cs_main); + pindexHeader = pindexBestHeader; + + if (pindexHeader != pindexHeaderOld) { + fNotify = true; + fInitialBlockDownload = IsInitialBlockDownload(); + pindexHeaderOld = pindexHeader; + } + } + // Send block tip changed notifications without cs_main + if (fNotify) { + uiInterface.NotifyHeaderTip(fInitialBlockDownload, pindexHeader); + } +} + +/** + * Make the best chain active, in multiple steps. The result is either failure + * or an activated best chain. pblock is either nullptr or a pointer to a block + * that is already loaded (to avoid loading it again from disk). + * + * ActivateBestChain is split into steps (see ActivateBestChainStep) so that + * we avoid holding cs_main for an extended period of time; the length of this + * call may be quite long during reindexing or a substantial reorg. + */ +bool CChainState::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! + AssertLockNotHeld(cs_main); + + // ABC maintains a fair degree of expensive-to-calculate internal state + // because this function periodically releases cs_main so that it does not lock up other threads for too long + // during large connects - and to allow for e.g. the callback queue to drain + // we use m_cs_chainstate to enforce mutual exclusion so that only one caller may execute this function at a time + LOCK(m_cs_chainstate); + + CBlockIndex *pindexMostWork = nullptr; + CBlockIndex *pindexNewTip = nullptr; + int nStopAtHeight = gArgs.GetArg("-stopatheight", DEFAULT_STOPATHEIGHT); + do { + boost::this_thread::interruption_point(); + + if (GetMainSignals().CallbacksPending() > 10) { + // Block until the validation queue drains. This should largely + // never happen in normal operation, however may happen during + // reindex, causing memory blowup if we run too far ahead. + // Note that if a validationinterface callback ends up calling + // ActivateBestChain this may lead to a deadlock! We should + // probably have a DEBUG_LOCKORDER test for this in the future. + SyncWithValidationInterfaceQueue(); + } + + { + LOCK(cs_main); + CBlockIndex* starting_tip = chainActive.Tip(); + bool blocks_connected = false; + do { + // We absolutely may not unlock cs_main until we've made forward progress + // (with the exception of shutdown due to hardware issues, low disk space, etc). + ConnectTrace connectTrace(mempool); // Destructed before cs_main is unlocked + + if (pindexMostWork == nullptr) { + pindexMostWork = FindMostWorkChain(); + } + + // Whether we have anything to do at all. + if (pindexMostWork == nullptr || pindexMostWork == chainActive.Tip()) { + break; + } + + bool fInvalidFound = false; + std::shared_ptr<const CBlock> nullBlockPtr; + if (!ActivateBestChainStep(state, chainparams, pindexMostWork, pblock && pblock->GetHash() == pindexMostWork->GetBlockHash() ? pblock : nullBlockPtr, fInvalidFound, connectTrace)) + return false; + blocks_connected = true; + + if (fInvalidFound) { + // Wipe cache, we may need another branch now. + pindexMostWork = nullptr; + } + pindexNewTip = chainActive.Tip(); + + for (const PerBlockConnectTrace& trace : connectTrace.GetBlocksConnected()) { + assert(trace.pblock && trace.pindex); + GetMainSignals().BlockConnected(trace.pblock, trace.pindex, trace.conflictedTxs); + } + } while (!chainActive.Tip() || (starting_tip && CBlockIndexWorkComparator()(chainActive.Tip(), starting_tip))); + if (!blocks_connected) return true; + + const CBlockIndex* pindexFork = chainActive.FindFork(starting_tip); + bool fInitialDownload = IsInitialBlockDownload(); + + // Notify external listeners about the new tip. + // Enqueue while holding cs_main to ensure that UpdatedBlockTip is called in the order in which blocks are connected + if (pindexFork != pindexNewTip) { + // Notify ValidationInterface subscribers + GetMainSignals().UpdatedBlockTip(pindexNewTip, pindexFork, fInitialDownload); + + // Always notify the UI if a new block tip was connected + uiInterface.NotifyBlockTip(fInitialDownload, pindexNewTip); + } + } + // When we reach this point, we switched to a new tip (stored in pindexNewTip). + + if (nStopAtHeight && pindexNewTip && pindexNewTip->nHeight >= nStopAtHeight) StartShutdown(); + + // We check shutdown only after giving ActivateBestChainStep a chance to run once so that we + // never shutdown before connecting the genesis block during LoadChainTip(). Previously this + // caused an assert() failure during shutdown in such cases as the UTXO DB flushing checks + // that the best block hash is non-null. + if (ShutdownRequested()) + break; + } while (pindexNewTip != pindexMostWork); + CheckBlockIndex(chainparams.GetConsensus()); + + // Write changes periodically to disk, after relay. + if (!FlushStateToDisk(chainparams, state, FlushStateMode::PERIODIC)) { + return false; + } + + return true; +} + +bool ActivateBestChain(CValidationState &state, const CChainParams& chainparams, std::shared_ptr<const CBlock> pblock) { + return g_chainstate.ActivateBestChain(state, chainparams, std::move(pblock)); +} + +bool CChainState::PreciousBlock(CValidationState& state, const CChainParams& params, CBlockIndex *pindex) +{ + { + LOCK(cs_main); + if (pindex->nChainWork < chainActive.Tip()->nChainWork) { + // Nothing to do, this block is not at the tip. + return true; + } + if (chainActive.Tip()->nChainWork > nLastPreciousChainwork) { + // The chain has been extended since the last call, reset the counter. + nBlockReverseSequenceId = -1; + } + nLastPreciousChainwork = chainActive.Tip()->nChainWork; + setBlockIndexCandidates.erase(pindex); + pindex->nSequenceId = nBlockReverseSequenceId; + if (nBlockReverseSequenceId > std::numeric_limits<int32_t>::min()) { + // We can't keep reducing the counter if somebody really wants to + // call preciousblock 2**31-1 times on the same set of tips... + nBlockReverseSequenceId--; + } + if (pindex->IsValid(BLOCK_VALID_TRANSACTIONS) && pindex->nChainTx) { + setBlockIndexCandidates.insert(pindex); + PruneBlockIndexCandidates(); + } + } + + return ActivateBestChain(state, params, std::shared_ptr<const CBlock>()); +} +bool PreciousBlock(CValidationState& state, const CChainParams& params, CBlockIndex *pindex) { + return g_chainstate.PreciousBlock(state, params, pindex); +} + +bool CChainState::InvalidateBlock(CValidationState& state, const CChainParams& chainparams, CBlockIndex *pindex) +{ + AssertLockHeld(cs_main); + + // We first disconnect backwards and then mark the blocks as invalid. + // This prevents a case where pruned nodes may fail to invalidateblock + // and be left unable to start as they have no tip candidates (as there + // are no blocks that meet the "have data and are not invalid per + // nStatus" criteria for inclusion in setBlockIndexCandidates). + + bool pindex_was_in_chain = false; + CBlockIndex *invalid_walk_tip = chainActive.Tip(); + + DisconnectedBlockTransactions disconnectpool; + while (chainActive.Contains(pindex)) { + pindex_was_in_chain = true; + // ActivateBestChain considers blocks already in chainActive + // unconditionally valid already, so force disconnect away from it. + if (!DisconnectTip(state, chainparams, &disconnectpool)) { + // It's probably hopeless to try to make the mempool consistent + // here if DisconnectTip failed, but we can try. + UpdateMempoolForReorg(disconnectpool, false); + return false; + } + } + + // Now mark the blocks we just disconnected as descendants invalid + // (note this may not be all descendants). + while (pindex_was_in_chain && invalid_walk_tip != pindex) { + invalid_walk_tip->nStatus |= BLOCK_FAILED_CHILD; + setDirtyBlockIndex.insert(invalid_walk_tip); + setBlockIndexCandidates.erase(invalid_walk_tip); + invalid_walk_tip = invalid_walk_tip->pprev; + } + + // Mark the block itself as invalid. + pindex->nStatus |= BLOCK_FAILED_VALID; + setDirtyBlockIndex.insert(pindex); + setBlockIndexCandidates.erase(pindex); + m_failed_blocks.insert(pindex); + + // DisconnectTip will add transactions to disconnectpool; try to add these + // back to the mempool. + UpdateMempoolForReorg(disconnectpool, true); + + // The resulting new best tip may not be in setBlockIndexCandidates anymore, so + // add it again. + BlockMap::iterator it = mapBlockIndex.begin(); + while (it != mapBlockIndex.end()) { + if (it->second->IsValid(BLOCK_VALID_TRANSACTIONS) && it->second->nChainTx && !setBlockIndexCandidates.value_comp()(it->second, chainActive.Tip())) { + setBlockIndexCandidates.insert(it->second); + } + it++; + } + + InvalidChainFound(pindex); + + // Only notify about a new block tip if the active chain was modified. + if (pindex_was_in_chain) { + uiInterface.NotifyBlockTip(IsInitialBlockDownload(), pindex->pprev); + } + return true; +} +bool InvalidateBlock(CValidationState& state, const CChainParams& chainparams, CBlockIndex *pindex) { + return g_chainstate.InvalidateBlock(state, chainparams, pindex); +} + +void CChainState::ResetBlockFailureFlags(CBlockIndex *pindex) { + AssertLockHeld(cs_main); + + int nHeight = pindex->nHeight; + + // Remove the invalidity flag from this block and all its descendants. + BlockMap::iterator it = mapBlockIndex.begin(); + while (it != mapBlockIndex.end()) { + if (!it->second->IsValid() && it->second->GetAncestor(nHeight) == pindex) { + it->second->nStatus &= ~BLOCK_FAILED_MASK; + setDirtyBlockIndex.insert(it->second); + if (it->second->IsValid(BLOCK_VALID_TRANSACTIONS) && it->second->nChainTx && setBlockIndexCandidates.value_comp()(chainActive.Tip(), it->second)) { + setBlockIndexCandidates.insert(it->second); + } + if (it->second == pindexBestInvalid) { + // Reset invalid block marker if it was pointing to one of those. + pindexBestInvalid = nullptr; + } + m_failed_blocks.erase(it->second); + } + it++; + } + + // Remove the invalidity flag from all ancestors too. + while (pindex != nullptr) { + if (pindex->nStatus & BLOCK_FAILED_MASK) { + pindex->nStatus &= ~BLOCK_FAILED_MASK; + setDirtyBlockIndex.insert(pindex); + m_failed_blocks.erase(pindex); + } + pindex = pindex->pprev; + } +} + +void ResetBlockFailureFlags(CBlockIndex *pindex) { + return g_chainstate.ResetBlockFailureFlags(pindex); +} + +CBlockIndex* CChainState::AddToBlockIndex(const CBlockHeader& block) +{ + AssertLockHeld(cs_main); + + // Check for duplicate + uint256 hash = block.GetHash(); + BlockMap::iterator it = mapBlockIndex.find(hash); + if (it != mapBlockIndex.end()) + return it->second; + + // Construct new block index object + CBlockIndex* pindexNew = new CBlockIndex(block); + // We assign the sequence id to blocks only when the full data is available, + // to avoid miners withholding blocks but broadcasting headers, to get a + // competitive advantage. + pindexNew->nSequenceId = 0; + BlockMap::iterator mi = mapBlockIndex.insert(std::make_pair(hash, pindexNew)).first; + pindexNew->phashBlock = &((*mi).first); + BlockMap::iterator miPrev = mapBlockIndex.find(block.hashPrevBlock); + if (miPrev != mapBlockIndex.end()) + { + pindexNew->pprev = (*miPrev).second; + 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 == nullptr || pindexBestHeader->nChainWork < pindexNew->nChainWork) + pindexBestHeader = pindexNew; + + setDirtyBlockIndex.insert(pindexNew); + + return pindexNew; +} + +/** Mark a block as having its data received and checked (up to BLOCK_VALID_TRANSACTIONS). */ +void CChainState::ReceivedBlockTransactions(const CBlock& block, CBlockIndex* pindexNew, const CDiskBlockPos& pos, const Consensus::Params& consensusParams) +{ + pindexNew->nTx = block.vtx.size(); + pindexNew->nChainTx = 0; + pindexNew->nFile = pos.nFile; + pindexNew->nDataPos = pos.nPos; + pindexNew->nUndoPos = 0; + pindexNew->nStatus |= BLOCK_HAVE_DATA; + if (IsWitnessEnabled(pindexNew->pprev, consensusParams)) { + pindexNew->nStatus |= BLOCK_OPT_WITNESS; + } + pindexNew->RaiseValidity(BLOCK_VALID_TRANSACTIONS); + setDirtyBlockIndex.insert(pindexNew); + + if (pindexNew->pprev == nullptr || pindexNew->pprev->nChainTx) { + // If pindexNew is the genesis block or all parents are BLOCK_VALID_TRANSACTIONS. + std::deque<CBlockIndex*> queue; + queue.push_back(pindexNew); + + // Recursively process any descendant blocks that now may be eligible to be connected. + while (!queue.empty()) { + CBlockIndex *pindex = queue.front(); + queue.pop_front(); + pindex->nChainTx = (pindex->pprev ? pindex->pprev->nChainTx : 0) + pindex->nTx; + { + LOCK(cs_nBlockSequenceId); + pindex->nSequenceId = nBlockSequenceId++; + } + if (chainActive.Tip() == nullptr || !setBlockIndexCandidates.value_comp()(pindex, chainActive.Tip())) { + setBlockIndexCandidates.insert(pindex); + } + std::pair<std::multimap<CBlockIndex*, CBlockIndex*>::iterator, std::multimap<CBlockIndex*, CBlockIndex*>::iterator> range = mapBlocksUnlinked.equal_range(pindex); + while (range.first != range.second) { + std::multimap<CBlockIndex*, CBlockIndex*>::iterator it = range.first; + queue.push_back(it->second); + range.first++; + mapBlocksUnlinked.erase(it); + } + } + } else { + if (pindexNew->pprev && pindexNew->pprev->IsValid(BLOCK_VALID_TREE)) { + mapBlocksUnlinked.insert(std::make_pair(pindexNew->pprev, pindexNew)); + } + } +} + +static bool FindBlockPos(CDiskBlockPos &pos, unsigned int nAddSize, unsigned int nHeight, uint64_t nTime, bool fKnown = false) +{ + LOCK(cs_LastBlockFile); + + unsigned int nFile = fKnown ? pos.nFile : nLastBlockFile; + if (vinfoBlockFile.size() <= nFile) { + vinfoBlockFile.resize(nFile + 1); + } + + if (!fKnown) { + while (vinfoBlockFile[nFile].nSize + nAddSize >= MAX_BLOCKFILE_SIZE) { + nFile++; + if (vinfoBlockFile.size() <= nFile) { + vinfoBlockFile.resize(nFile + 1); + } + } + pos.nFile = nFile; + pos.nPos = vinfoBlockFile[nFile].nSize; + } + + if ((int)nFile != nLastBlockFile) { + if (!fKnown) { + LogPrintf("Leaving block file %i: %s\n", nLastBlockFile, vinfoBlockFile[nLastBlockFile].ToString()); + } + FlushBlockFile(!fKnown); + nLastBlockFile = nFile; + } + + vinfoBlockFile[nFile].AddBlock(nHeight, nTime); + if (fKnown) + vinfoBlockFile[nFile].nSize = std::max(pos.nPos + nAddSize, vinfoBlockFile[nFile].nSize); + else + vinfoBlockFile[nFile].nSize += nAddSize; + + if (!fKnown) { + unsigned int nOldChunks = (pos.nPos + BLOCKFILE_CHUNK_SIZE - 1) / BLOCKFILE_CHUNK_SIZE; + unsigned int nNewChunks = (vinfoBlockFile[nFile].nSize + BLOCKFILE_CHUNK_SIZE - 1) / BLOCKFILE_CHUNK_SIZE; + if (nNewChunks > nOldChunks) { + if (fPruneMode) + fCheckForPruning = true; + if (CheckDiskSpace(nNewChunks * BLOCKFILE_CHUNK_SIZE - pos.nPos, true)) { + FILE *file = OpenBlockFile(pos); + if (file) { + LogPrintf("Pre-allocating up to position 0x%x in blk%05u.dat\n", nNewChunks * BLOCKFILE_CHUNK_SIZE, pos.nFile); + AllocateFileRange(file, pos.nPos, nNewChunks * BLOCKFILE_CHUNK_SIZE - pos.nPos); + fclose(file); + } + } + else + return error("out of disk space"); + } + } + + setDirtyFileInfo.insert(nFile); + return true; +} + +static bool FindUndoPos(CValidationState &state, int nFile, CDiskBlockPos &pos, unsigned int nAddSize) +{ + pos.nFile = nFile; + + LOCK(cs_LastBlockFile); + + unsigned int nNewSize; + pos.nPos = vinfoBlockFile[nFile].nUndoSize; + nNewSize = vinfoBlockFile[nFile].nUndoSize += nAddSize; + setDirtyFileInfo.insert(nFile); + + unsigned int nOldChunks = (pos.nPos + UNDOFILE_CHUNK_SIZE - 1) / UNDOFILE_CHUNK_SIZE; + unsigned int nNewChunks = (nNewSize + UNDOFILE_CHUNK_SIZE - 1) / UNDOFILE_CHUNK_SIZE; + if (nNewChunks > nOldChunks) { + if (fPruneMode) + fCheckForPruning = true; + if (CheckDiskSpace(nNewChunks * UNDOFILE_CHUNK_SIZE - pos.nPos, true)) { + FILE *file = OpenUndoFile(pos); + if (file) { + LogPrintf("Pre-allocating up to position 0x%x in rev%05u.dat\n", nNewChunks * UNDOFILE_CHUNK_SIZE, pos.nFile); + AllocateFileRange(file, pos.nPos, nNewChunks * UNDOFILE_CHUNK_SIZE - pos.nPos); + fclose(file); + } + } + else + return state.Error("out of disk space"); + } + + return true; +} + +static bool CheckBlockHeader(const CBlockHeader& block, CValidationState& state, const Consensus::Params& consensusParams, bool fCheckPOW = true) +{ + // Check proof of work matches claimed amount + if (fCheckPOW && !CheckProofOfWork(block.GetHash(), block.nBits, consensusParams)) + return state.DoS(50, false, REJECT_INVALID, "high-hash", false, "proof of work failed"); + + return true; +} + +bool CheckBlock(const CBlock& block, CValidationState& state, const Consensus::Params& consensusParams, bool fCheckPOW, bool fCheckMerkleRoot) +{ + // These are checks that are independent of context. + + if (block.fChecked) + return true; + + // Check that the header is valid (particularly PoW). This is mostly + // redundant with the call in AcceptBlockHeader. + if (!CheckBlockHeader(block, state, consensusParams, fCheckPOW)) + return false; + + // Check the merkle root. + if (fCheckMerkleRoot) { + bool mutated; + uint256 hashMerkleRoot2 = BlockMerkleRoot(block, &mutated); + if (block.hashMerkleRoot != hashMerkleRoot2) + return state.DoS(100, false, REJECT_INVALID, "bad-txnmrklroot", true, "hashMerkleRoot mismatch"); + + // Check for merkle tree malleability (CVE-2012-2459): repeating sequences + // of transactions in a block without affecting the merkle root of a block, + // while still invalidating it. + if (mutated) + return state.DoS(100, false, REJECT_INVALID, "bad-txns-duplicate", true, "duplicate transaction"); + } + + // All potential-corruption validation must be done before we do any + // transaction validation, as otherwise we may mark the header as invalid + // because we receive the wrong transactions for it. + // Note that witness malleability is checked in ContextualCheckBlock, so no + // checks that use witness data may be performed here. + + // Size limits + if (block.vtx.empty() || block.vtx.size() * WITNESS_SCALE_FACTOR > MAX_BLOCK_WEIGHT || ::GetSerializeSize(block, SER_NETWORK, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS) * WITNESS_SCALE_FACTOR > MAX_BLOCK_WEIGHT) + return state.DoS(100, false, REJECT_INVALID, "bad-blk-length", false, "size limits failed"); + + // First transaction must be coinbase, the rest must not be + if (block.vtx.empty() || !block.vtx[0]->IsCoinBase()) + return state.DoS(100, false, REJECT_INVALID, "bad-cb-missing", false, "first tx is not coinbase"); + for (unsigned int i = 1; i < block.vtx.size(); i++) + if (block.vtx[i]->IsCoinBase()) + return state.DoS(100, false, REJECT_INVALID, "bad-cb-multiple", false, "more than one coinbase"); + + // Check transactions + for (const auto& tx : block.vtx) + if (!CheckTransaction(*tx, state, false)) + return state.Invalid(false, state.GetRejectCode(), state.GetRejectReason(), + strprintf("Transaction check failed (tx hash %s) %s", tx->GetHash().ToString(), state.GetDebugMessage())); + + unsigned int nSigOps = 0; + for (const auto& tx : block.vtx) + { + nSigOps += GetLegacySigOpCount(*tx); + } + if (nSigOps * WITNESS_SCALE_FACTOR > MAX_BLOCK_SIGOPS_COST) + return state.DoS(100, false, REJECT_INVALID, "bad-blk-sigops", false, "out-of-bounds SigOpCount"); + + if (fCheckPOW && fCheckMerkleRoot) + block.fChecked = true; + + return true; +} + +bool IsWitnessEnabled(const CBlockIndex* pindexPrev, const Consensus::Params& params) +{ + LOCK(cs_main); + return (VersionBitsState(pindexPrev, params, Consensus::DEPLOYMENT_SEGWIT, versionbitscache) == ThresholdState::ACTIVE); +} + +bool IsNullDummyEnabled(const CBlockIndex* pindexPrev, const Consensus::Params& params) +{ + LOCK(cs_main); + return (VersionBitsState(pindexPrev, params, Consensus::DEPLOYMENT_SEGWIT, versionbitscache) == ThresholdState::ACTIVE); +} + +// Compute at which vout of the block's coinbase transaction the witness +// commitment occurs, or -1 if not found. +static int GetWitnessCommitmentIndex(const CBlock& block) +{ + int commitpos = -1; + if (!block.vtx.empty()) { + for (size_t o = 0; o < block.vtx[0]->vout.size(); o++) { + if (block.vtx[0]->vout[o].scriptPubKey.size() >= 38 && block.vtx[0]->vout[o].scriptPubKey[0] == OP_RETURN && block.vtx[0]->vout[o].scriptPubKey[1] == 0x24 && block.vtx[0]->vout[o].scriptPubKey[2] == 0xaa && block.vtx[0]->vout[o].scriptPubKey[3] == 0x21 && block.vtx[0]->vout[o].scriptPubKey[4] == 0xa9 && block.vtx[0]->vout[o].scriptPubKey[5] == 0xed) { + commitpos = o; + } + } + } + return commitpos; +} + +void UpdateUncommittedBlockStructures(CBlock& block, const CBlockIndex* pindexPrev, const Consensus::Params& consensusParams) +{ + int commitpos = GetWitnessCommitmentIndex(block); + static const std::vector<unsigned char> nonce(32, 0x00); + if (commitpos != -1 && IsWitnessEnabled(pindexPrev, consensusParams) && !block.vtx[0]->HasWitness()) { + CMutableTransaction tx(*block.vtx[0]); + tx.vin[0].scriptWitness.stack.resize(1); + tx.vin[0].scriptWitness.stack[0] = nonce; + block.vtx[0] = MakeTransactionRef(std::move(tx)); + } +} + +std::vector<unsigned char> GenerateCoinbaseCommitment(CBlock& block, const CBlockIndex* pindexPrev, const Consensus::Params& consensusParams) +{ + std::vector<unsigned char> commitment; + int commitpos = GetWitnessCommitmentIndex(block); + std::vector<unsigned char> ret(32, 0x00); + if (consensusParams.vDeployments[Consensus::DEPLOYMENT_SEGWIT].nTimeout != 0) { + if (commitpos == -1) { + uint256 witnessroot = BlockWitnessMerkleRoot(block, nullptr); + CHash256().Write(witnessroot.begin(), 32).Write(ret.data(), 32).Finalize(witnessroot.begin()); + CTxOut out; + out.nValue = 0; + out.scriptPubKey.resize(38); + out.scriptPubKey[0] = OP_RETURN; + out.scriptPubKey[1] = 0x24; + out.scriptPubKey[2] = 0xaa; + out.scriptPubKey[3] = 0x21; + out.scriptPubKey[4] = 0xa9; + out.scriptPubKey[5] = 0xed; + memcpy(&out.scriptPubKey[6], witnessroot.begin(), 32); + commitment = std::vector<unsigned char>(out.scriptPubKey.begin(), out.scriptPubKey.end()); + CMutableTransaction tx(*block.vtx[0]); + tx.vout.push_back(out); + block.vtx[0] = MakeTransactionRef(std::move(tx)); + } + } + UpdateUncommittedBlockStructures(block, pindexPrev, consensusParams); + return commitment; +} + +/** Context-dependent validity checks. + * By "context", we mean only the previous block headers, but not the UTXO + * set; UTXO-related validity checks are done in ConnectBlock(). + * NOTE: This function is not currently invoked by ConnectBlock(), so we + * should consider upgrade issues if we change which consensus rules are + * enforced in this function (eg by adding a new consensus rule). See comment + * in ConnectBlock(). + * Note that -reindex-chainstate skips the validation that happens here! + */ +static bool ContextualCheckBlockHeader(const CBlockHeader& block, CValidationState& state, const CChainParams& params, const CBlockIndex* pindexPrev, int64_t nAdjustedTime) +{ + assert(pindexPrev != nullptr); + const int nHeight = pindexPrev->nHeight + 1; + + // Check proof of work + const Consensus::Params& consensusParams = params.GetConsensus(); + if (block.nBits != GetNextWorkRequired(pindexPrev, &block, consensusParams)) + return state.DoS(100, false, REJECT_INVALID, "bad-diffbits", false, "incorrect proof of work"); + + // Check against checkpoints + if (fCheckpointsEnabled) { + // Don't accept any forks from the main chain prior to last checkpoint. + // GetLastCheckpoint finds the last checkpoint in MapCheckpoints that's in our + // MapBlockIndex. + CBlockIndex* pcheckpoint = Checkpoints::GetLastCheckpoint(params.Checkpoints()); + if (pcheckpoint && nHeight < pcheckpoint->nHeight) + return state.DoS(100, error("%s: forked chain older than last checkpoint (height %d)", __func__, nHeight), REJECT_CHECKPOINT, "bad-fork-prior-to-checkpoint"); + } + + // Check timestamp against prev + if (block.GetBlockTime() <= pindexPrev->GetMedianTimePast()) + return state.Invalid(false, REJECT_INVALID, "time-too-old", "block's timestamp is too early"); + + // Check timestamp + if (block.GetBlockTime() > nAdjustedTime + MAX_FUTURE_BLOCK_TIME) + return state.Invalid(false, REJECT_INVALID, "time-too-new", "block timestamp too far in the future"); + + // Reject outdated version blocks when 95% (75% on testnet) of the network has upgraded: + // check for version 2, 3 and 4 upgrades + if((block.nVersion < 2 && nHeight >= consensusParams.BIP34Height) || + (block.nVersion < 3 && nHeight >= consensusParams.BIP66Height) || + (block.nVersion < 4 && nHeight >= consensusParams.BIP65Height)) + return state.Invalid(false, REJECT_OBSOLETE, strprintf("bad-version(0x%08x)", block.nVersion), + strprintf("rejected nVersion=0x%08x block", block.nVersion)); + + return true; +} + +/** NOTE: This function is not currently invoked by ConnectBlock(), so we + * should consider upgrade issues if we change which consensus rules are + * enforced in this function (eg by adding a new consensus rule). See comment + * in ConnectBlock(). + * Note that -reindex-chainstate skips the validation that happens here! + */ +static bool ContextualCheckBlock(const CBlock& block, CValidationState& state, const Consensus::Params& consensusParams, const CBlockIndex* pindexPrev) +{ + const int nHeight = pindexPrev == nullptr ? 0 : pindexPrev->nHeight + 1; + + // Start enforcing BIP113 (Median Time Past) using versionbits logic. + int nLockTimeFlags = 0; + if (VersionBitsState(pindexPrev, consensusParams, Consensus::DEPLOYMENT_CSV, versionbitscache) == ThresholdState::ACTIVE) { + nLockTimeFlags |= LOCKTIME_MEDIAN_TIME_PAST; + } + + int64_t nLockTimeCutoff = (nLockTimeFlags & LOCKTIME_MEDIAN_TIME_PAST) + ? pindexPrev->GetMedianTimePast() + : block.GetBlockTime(); + + // Check that all transactions are finalized + for (const auto& tx : block.vtx) { + if (!IsFinalTx(*tx, nHeight, nLockTimeCutoff)) { + return state.DoS(10, false, REJECT_INVALID, "bad-txns-nonfinal", false, "non-final transaction"); + } + } + + // Enforce rule that the coinbase starts with serialized block height + if (nHeight >= consensusParams.BIP34Height) + { + CScript expect = CScript() << nHeight; + if (block.vtx[0]->vin[0].scriptSig.size() < expect.size() || + !std::equal(expect.begin(), expect.end(), block.vtx[0]->vin[0].scriptSig.begin())) { + return state.DoS(100, false, REJECT_INVALID, "bad-cb-height", false, "block height mismatch in coinbase"); + } + } + + // Validation for witness commitments. + // * We compute the witness hash (which is the hash including witnesses) of all the block's transactions, except the + // coinbase (where 0x0000....0000 is used instead). + // * The coinbase scriptWitness is a stack of a single 32-byte vector, containing a witness reserved value (unconstrained). + // * We build a merkle tree with all those witness hashes as leaves (similar to the hashMerkleRoot in the block header). + // * There must be at least one output whose scriptPubKey is a single 36-byte push, the first 4 bytes of which are + // {0xaa, 0x21, 0xa9, 0xed}, and the following 32 bytes are SHA256^2(witness root, witness reserved value). In case there are + // multiple, the last one is used. + bool fHaveWitness = false; + if (VersionBitsState(pindexPrev, consensusParams, Consensus::DEPLOYMENT_SEGWIT, versionbitscache) == ThresholdState::ACTIVE) { + int commitpos = GetWitnessCommitmentIndex(block); + if (commitpos != -1) { + bool malleated = false; + uint256 hashWitness = BlockWitnessMerkleRoot(block, &malleated); + // The malleation check is ignored; as the transaction tree itself + // already does not permit it, it is impossible to trigger in the + // witness tree. + if (block.vtx[0]->vin[0].scriptWitness.stack.size() != 1 || block.vtx[0]->vin[0].scriptWitness.stack[0].size() != 32) { + return state.DoS(100, false, REJECT_INVALID, "bad-witness-nonce-size", true, strprintf("%s : invalid witness reserved value size", __func__)); + } + CHash256().Write(hashWitness.begin(), 32).Write(&block.vtx[0]->vin[0].scriptWitness.stack[0][0], 32).Finalize(hashWitness.begin()); + if (memcmp(hashWitness.begin(), &block.vtx[0]->vout[commitpos].scriptPubKey[6], 32)) { + return state.DoS(100, false, REJECT_INVALID, "bad-witness-merkle-match", true, strprintf("%s : witness merkle commitment mismatch", __func__)); + } + fHaveWitness = true; + } + } + + // No witness data is allowed in blocks that don't commit to witness data, as this would otherwise leave room for spam + if (!fHaveWitness) { + for (const auto& tx : block.vtx) { + if (tx->HasWitness()) { + return state.DoS(100, false, REJECT_INVALID, "unexpected-witness", true, strprintf("%s : unexpected witness data found", __func__)); + } + } + } + + // After the coinbase witness reserved value and commitment are verified, + // we can check if the block weight passes (before we've checked the + // coinbase witness, it would be possible for the weight to be too + // large by filling up the coinbase witness, which doesn't change + // the block hash, so we couldn't mark the block as permanently + // failed). + if (GetBlockWeight(block) > MAX_BLOCK_WEIGHT) { + return state.DoS(100, false, REJECT_INVALID, "bad-blk-weight", false, strprintf("%s : weight limit failed", __func__)); + } + + return true; +} + +bool CChainState::AcceptBlockHeader(const CBlockHeader& block, CValidationState& state, const CChainParams& chainparams, CBlockIndex** ppindex) +{ + AssertLockHeld(cs_main); + // Check for duplicate + uint256 hash = block.GetHash(); + BlockMap::iterator miSelf = mapBlockIndex.find(hash); + CBlockIndex *pindex = nullptr; + if (hash != chainparams.GetConsensus().hashGenesisBlock) { + if (miSelf != mapBlockIndex.end()) { + // Block header is already known. + pindex = miSelf->second; + if (ppindex) + *ppindex = pindex; + if (pindex->nStatus & BLOCK_FAILED_MASK) + return state.Invalid(error("%s: block %s is marked invalid", __func__, hash.ToString()), 0, "duplicate"); + return true; + } + + if (!CheckBlockHeader(block, state, chainparams.GetConsensus())) + return error("%s: Consensus::CheckBlockHeader: %s, %s", __func__, hash.ToString(), FormatStateMessage(state)); + + // Get prev block index + CBlockIndex* pindexPrev = nullptr; + BlockMap::iterator mi = mapBlockIndex.find(block.hashPrevBlock); + if (mi == mapBlockIndex.end()) + return state.DoS(10, error("%s: prev block not found", __func__), 0, "prev-blk-not-found"); + pindexPrev = (*mi).second; + if (pindexPrev->nStatus & BLOCK_FAILED_MASK) + return state.DoS(100, error("%s: prev block invalid", __func__), REJECT_INVALID, "bad-prevblk"); + if (!ContextualCheckBlockHeader(block, state, chainparams, pindexPrev, GetAdjustedTime())) + return error("%s: Consensus::ContextualCheckBlockHeader: %s, %s", __func__, hash.ToString(), FormatStateMessage(state)); + + // If the previous block index isn't valid, determine if it descends from any block which + // has been found invalid (m_failed_blocks), then mark pindexPrev and any blocks + // between them as failed. + if (!pindexPrev->IsValid(BLOCK_VALID_SCRIPTS)) { + for (const CBlockIndex* failedit : m_failed_blocks) { + if (pindexPrev->GetAncestor(failedit->nHeight) == failedit) { + assert(failedit->nStatus & BLOCK_FAILED_VALID); + CBlockIndex* invalid_walk = pindexPrev; + while (invalid_walk != failedit) { + invalid_walk->nStatus |= BLOCK_FAILED_CHILD; + setDirtyBlockIndex.insert(invalid_walk); + invalid_walk = invalid_walk->pprev; + } + return state.DoS(100, error("%s: prev block invalid", __func__), REJECT_INVALID, "bad-prevblk"); + } + } + } + } + if (pindex == nullptr) + pindex = AddToBlockIndex(block); + + if (ppindex) + *ppindex = pindex; + + CheckBlockIndex(chainparams.GetConsensus()); + + return true; +} + +// Exposed wrapper for AcceptBlockHeader +bool ProcessNewBlockHeaders(const std::vector<CBlockHeader>& headers, CValidationState& state, const CChainParams& chainparams, const CBlockIndex** ppindex, CBlockHeader *first_invalid) +{ + if (first_invalid != nullptr) first_invalid->SetNull(); + { + LOCK(cs_main); + for (const CBlockHeader& header : headers) { + CBlockIndex *pindex = nullptr; // Use a temp pindex instead of ppindex to avoid a const_cast + if (!g_chainstate.AcceptBlockHeader(header, state, chainparams, &pindex)) { + if (first_invalid) *first_invalid = header; + return false; + } + if (ppindex) { + *ppindex = pindex; + } + } + } + NotifyHeaderTip(); + return true; +} + +/** Store block on disk. If dbp is non-nullptr, the file is known to already reside on disk */ +static CDiskBlockPos SaveBlockToDisk(const CBlock& block, int nHeight, const CChainParams& chainparams, const CDiskBlockPos* dbp) { + unsigned int nBlockSize = ::GetSerializeSize(block, SER_DISK, CLIENT_VERSION); + CDiskBlockPos blockPos; + if (dbp != nullptr) + blockPos = *dbp; + if (!FindBlockPos(blockPos, nBlockSize+8, nHeight, block.GetBlockTime(), dbp != nullptr)) { + error("%s: FindBlockPos failed", __func__); + return CDiskBlockPos(); + } + if (dbp == nullptr) { + if (!WriteBlockToDisk(block, blockPos, chainparams.MessageStart())) { + AbortNode("Failed to write block"); + return CDiskBlockPos(); + } + } + return blockPos; +} + +/** Store block on disk. If dbp is non-nullptr, the file is known to already reside on disk */ +bool CChainState::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); + + CBlockIndex *pindexDummy = nullptr; + CBlockIndex *&pindex = ppindex ? *ppindex : pindexDummy; + + if (!AcceptBlockHeader(block, state, chainparams, &pindex)) + return false; + + // Try to process all requested blocks that we don't have, but only + // process an unrequested block if it's new and has enough work to + // advance our tip, and isn't too many blocks ahead. + bool fAlreadyHave = pindex->nStatus & BLOCK_HAVE_DATA; + bool fHasMoreOrSameWork = (chainActive.Tip() ? pindex->nChainWork >= chainActive.Tip()->nChainWork : true); + // Blocks that are too out-of-order needlessly limit the effectiveness of + // pruning, because pruning will not delete block files that contain any + // blocks which are too close in height to the tip. Apply this test + // regardless of whether pruning is enabled; it should generally be safe to + // not process unrequested blocks. + bool fTooFarAhead = (pindex->nHeight > int(chainActive.Height() + MIN_BLOCKS_TO_KEEP)); + + // TODO: Decouple this function from the block download logic by removing fRequested + // This requires some new chain data structure to efficiently look up if a + // block is in a chain leading to a candidate for best tip, despite not + // being such a candidate itself. + + // TODO: deal better with return value and error conditions for duplicate + // and unrequested blocks. + if (fAlreadyHave) return true; + if (!fRequested) { // If we didn't ask for it: + if (pindex->nTx != 0) return true; // This is a previously-processed block that was pruned + if (!fHasMoreOrSameWork) return true; // Don't process less-work chains + if (fTooFarAhead) return true; // Block height is too high + + // Protect against DoS attacks from low-work chains. + // If our tip is behind, a peer could try to send us + // low-work blocks on a fake chain that we would never + // request; don't process these. + if (pindex->nChainWork < nMinimumChainWork) return true; + } + + if (!CheckBlock(block, state, chainparams.GetConsensus()) || + !ContextualCheckBlock(block, state, chainparams.GetConsensus(), pindex->pprev)) { + if (state.IsInvalid() && !state.CorruptionPossible()) { + pindex->nStatus |= BLOCK_FAILED_VALID; + setDirtyBlockIndex.insert(pindex); + } + 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); + + // Write block to history file + if (fNewBlock) *fNewBlock = true; + try { + CDiskBlockPos blockPos = SaveBlockToDisk(block, pindex->nHeight, chainparams, dbp); + if (blockPos.IsNull()) { + state.Error(strprintf("%s: Failed to find position to write new block to disk", __func__)); + return false; + } + ReceivedBlockTransactions(block, pindex, blockPos, chainparams.GetConsensus()); + } catch (const std::runtime_error& e) { + return AbortNode(state, std::string("System error: ") + e.what()); + } + + FlushStateToDisk(chainparams, state, FlushStateMode::NONE); + + CheckBlockIndex(chainparams.GetConsensus()); + + return true; +} + +bool ProcessNewBlock(const CChainParams& chainparams, const std::shared_ptr<const CBlock> pblock, bool fForceProcessing, bool *fNewBlock) +{ + AssertLockNotHeld(cs_main); + + { + CBlockIndex *pindex = nullptr; + if (fNewBlock) *fNewBlock = false; + CValidationState state; + // Ensure that CheckBlock() passes before calling AcceptBlock, as + // belt-and-suspenders. + bool ret = CheckBlock(*pblock, state, chainparams.GetConsensus()); + + LOCK(cs_main); + + if (ret) { + // Store to disk + ret = g_chainstate.AcceptBlock(pblock, state, chainparams, &pindex, fForceProcessing, nullptr, fNewBlock); + } + if (!ret) { + GetMainSignals().BlockChecked(*pblock, state); + return error("%s: AcceptBlock FAILED (%s)", __func__, FormatStateMessage(state)); + } + } + + NotifyHeaderTip(); + + CValidationState state; // Only used to report errors, not invalidity - ignore it + if (!g_chainstate.ActivateBestChain(state, chainparams, pblock)) + return error("%s: ActivateBestChain failed (%s)", __func__, FormatStateMessage(state)); + + return true; +} + +bool TestBlockValidity(CValidationState& state, const CChainParams& chainparams, const CBlock& block, CBlockIndex* pindexPrev, bool fCheckPOW, bool fCheckMerkleRoot) +{ + AssertLockHeld(cs_main); + assert(pindexPrev && pindexPrev == chainActive.Tip()); + CCoinsViewCache viewNew(pcoinsTip.get()); + uint256 block_hash(block.GetHash()); + CBlockIndex indexDummy(block); + indexDummy.pprev = pindexPrev; + indexDummy.nHeight = pindexPrev->nHeight + 1; + indexDummy.phashBlock = &block_hash; + + // NOTE: CheckBlockHeader is called by CheckBlock + if (!ContextualCheckBlockHeader(block, state, chainparams, pindexPrev, GetAdjustedTime())) + return error("%s: Consensus::ContextualCheckBlockHeader: %s", __func__, FormatStateMessage(state)); + if (!CheckBlock(block, state, chainparams.GetConsensus(), fCheckPOW, fCheckMerkleRoot)) + return error("%s: Consensus::CheckBlock: %s", __func__, FormatStateMessage(state)); + if (!ContextualCheckBlock(block, state, chainparams.GetConsensus(), pindexPrev)) + return error("%s: Consensus::ContextualCheckBlock: %s", __func__, FormatStateMessage(state)); + if (!g_chainstate.ConnectBlock(block, state, &indexDummy, viewNew, chainparams, true)) + return false; + assert(state.IsValid()); + + return true; +} + +/** + * BLOCK PRUNING CODE + */ + +/* Calculate the amount of disk space the block & undo files currently use */ +uint64_t CalculateCurrentUsage() +{ + LOCK(cs_LastBlockFile); + + uint64_t retval = 0; + for (const CBlockFileInfo &file : vinfoBlockFile) { + retval += file.nSize + file.nUndoSize; + } + return retval; +} + +/* Prune a block file (modify associated database entries)*/ +void PruneOneBlockFile(const int fileNumber) +{ + LOCK(cs_LastBlockFile); + + for (const auto& entry : mapBlockIndex) { + CBlockIndex* pindex = entry.second; + if (pindex->nFile == fileNumber) { + pindex->nStatus &= ~BLOCK_HAVE_DATA; + pindex->nStatus &= ~BLOCK_HAVE_UNDO; + pindex->nFile = 0; + pindex->nDataPos = 0; + pindex->nUndoPos = 0; + setDirtyBlockIndex.insert(pindex); + + // Prune from mapBlocksUnlinked -- any block we prune would have + // to be downloaded again in order to consider its chain, at which + // point it would be considered as a candidate for + // mapBlocksUnlinked or setBlockIndexCandidates. + std::pair<std::multimap<CBlockIndex*, CBlockIndex*>::iterator, std::multimap<CBlockIndex*, CBlockIndex*>::iterator> range = mapBlocksUnlinked.equal_range(pindex->pprev); + while (range.first != range.second) { + std::multimap<CBlockIndex *, CBlockIndex *>::iterator _it = range.first; + range.first++; + if (_it->second == pindex) { + mapBlocksUnlinked.erase(_it); + } + } + } + } + + vinfoBlockFile[fileNumber].SetNull(); + setDirtyFileInfo.insert(fileNumber); +} + + +void UnlinkPrunedFiles(const std::set<int>& setFilesToPrune) +{ + for (std::set<int>::iterator it = setFilesToPrune.begin(); it != setFilesToPrune.end(); ++it) { + CDiskBlockPos pos(*it, 0); + fs::remove(GetBlockPosFilename(pos, "blk")); + fs::remove(GetBlockPosFilename(pos, "rev")); + LogPrintf("Prune: %s deleted blk/rev (%05u)\n", __func__, *it); + } +} + +/* Calculate the block/rev files to delete based on height specified by user with RPC command pruneblockchain */ +static void FindFilesToPruneManual(std::set<int>& setFilesToPrune, int nManualPruneHeight) +{ + assert(fPruneMode && nManualPruneHeight > 0); + + LOCK2(cs_main, cs_LastBlockFile); + if (chainActive.Tip() == nullptr) + return; + + // last block to prune is the lesser of (user-specified height, MIN_BLOCKS_TO_KEEP from the tip) + unsigned int nLastBlockWeCanPrune = std::min((unsigned)nManualPruneHeight, chainActive.Tip()->nHeight - MIN_BLOCKS_TO_KEEP); + int count=0; + for (int fileNumber = 0; fileNumber < nLastBlockFile; fileNumber++) { + if (vinfoBlockFile[fileNumber].nSize == 0 || vinfoBlockFile[fileNumber].nHeightLast > nLastBlockWeCanPrune) + continue; + PruneOneBlockFile(fileNumber); + setFilesToPrune.insert(fileNumber); + count++; + } + LogPrintf("Prune (Manual): prune_height=%d removed %d blk/rev pairs\n", nLastBlockWeCanPrune, count); +} + +/* This function is called from the RPC code for pruneblockchain */ +void PruneBlockFilesManual(int nManualPruneHeight) +{ + CValidationState state; + const CChainParams& chainparams = Params(); + if (!FlushStateToDisk(chainparams, state, FlushStateMode::NONE, nManualPruneHeight)) { + LogPrintf("%s: failed to flush state (%s)\n", __func__, FormatStateMessage(state)); + } +} + +/** + * Prune block and undo files (blk???.dat and undo???.dat) so that the disk space used is less than a user-defined target. + * The user sets the target (in MB) on the command line or in config file. This will be run on startup and whenever new + * space is allocated in a block or undo file, staying below the target. Changing back to unpruned requires a reindex + * (which in this case means the blockchain must be re-downloaded.) + * + * Pruning functions are called from FlushStateToDisk when the global fCheckForPruning flag has been set. + * Block and undo files are deleted in lock-step (when blk00003.dat is deleted, so is rev00003.dat.) + * Pruning cannot take place until the longest chain is at least a certain length (100000 on mainnet, 1000 on testnet, 1000 on regtest). + * Pruning will never delete a block within a defined distance (currently 288) from the active chain's tip. + * The block index is updated by unsetting HAVE_DATA and HAVE_UNDO for any blocks that were stored in the deleted files. + * A db flag records the fact that at least some block files have been pruned. + * + * @param[out] setFilesToPrune The set of file indices that can be unlinked will be returned + */ +static void FindFilesToPrune(std::set<int>& setFilesToPrune, uint64_t nPruneAfterHeight) +{ + LOCK2(cs_main, cs_LastBlockFile); + if (chainActive.Tip() == nullptr || nPruneTarget == 0) { + return; + } + if ((uint64_t)chainActive.Tip()->nHeight <= nPruneAfterHeight) { + return; + } + + unsigned int nLastBlockWeCanPrune = chainActive.Tip()->nHeight - MIN_BLOCKS_TO_KEEP; + uint64_t nCurrentUsage = CalculateCurrentUsage(); + // We don't check to prune until after we've allocated new space for files + // So we should leave a buffer under our target to account for another allocation + // before the next pruning. + uint64_t nBuffer = BLOCKFILE_CHUNK_SIZE + UNDOFILE_CHUNK_SIZE; + uint64_t nBytesToPrune; + int count=0; + + if (nCurrentUsage + nBuffer >= nPruneTarget) { + // On a prune event, the chainstate DB is flushed. + // To avoid excessive prune events negating the benefit of high dbcache + // values, we should not prune too rapidly. + // So when pruning in IBD, increase the buffer a bit to avoid a re-prune too soon. + if (IsInitialBlockDownload()) { + // Since this is only relevant during IBD, we use a fixed 10% + nBuffer += nPruneTarget / 10; + } + + for (int fileNumber = 0; fileNumber < nLastBlockFile; fileNumber++) { + nBytesToPrune = vinfoBlockFile[fileNumber].nSize + vinfoBlockFile[fileNumber].nUndoSize; + + if (vinfoBlockFile[fileNumber].nSize == 0) + continue; + + if (nCurrentUsage + nBuffer < nPruneTarget) // are we below our target? + break; + + // don't prune files that could have a block within MIN_BLOCKS_TO_KEEP of the main chain's tip but keep scanning + if (vinfoBlockFile[fileNumber].nHeightLast > nLastBlockWeCanPrune) + continue; + + PruneOneBlockFile(fileNumber); + // Queue up the files for removal + setFilesToPrune.insert(fileNumber); + nCurrentUsage -= nBytesToPrune; + count++; + } + } + + LogPrint(BCLog::PRUNE, "Prune: target=%dMiB actual=%dMiB diff=%dMiB max_prune_height=%d removed %d blk/rev pairs\n", + nPruneTarget/1024/1024, nCurrentUsage/1024/1024, + ((int64_t)nPruneTarget - (int64_t)nCurrentUsage)/1024/1024, + nLastBlockWeCanPrune, count); +} + +bool CheckDiskSpace(uint64_t nAdditionalBytes, bool blocks_dir) +{ + uint64_t nFreeBytesAvailable = fs::space(blocks_dir ? GetBlocksDir() : GetDataDir()).available; + + // Check for nMinDiskSpace bytes (currently 50MB) + if (nFreeBytesAvailable < nMinDiskSpace + nAdditionalBytes) + return AbortNode("Disk space is low!", _("Error: Disk space is low!")); + + return true; +} + +static FILE* OpenDiskFile(const CDiskBlockPos &pos, const char *prefix, bool fReadOnly) +{ + if (pos.IsNull()) + return nullptr; + fs::path path = GetBlockPosFilename(pos, prefix); + fs::create_directories(path.parent_path()); + FILE* file = fsbridge::fopen(path, fReadOnly ? "rb": "rb+"); + if (!file && !fReadOnly) + file = fsbridge::fopen(path, "wb+"); + if (!file) { + LogPrintf("Unable to open file %s\n", path.string()); + return nullptr; + } + if (pos.nPos) { + if (fseek(file, pos.nPos, SEEK_SET)) { + LogPrintf("Unable to seek to position %u of %s\n", pos.nPos, path.string()); + fclose(file); + return nullptr; + } + } + return file; +} + +FILE* OpenBlockFile(const CDiskBlockPos &pos, bool fReadOnly) { + return OpenDiskFile(pos, "blk", fReadOnly); +} + +/** Open an undo file (rev?????.dat) */ +static FILE* OpenUndoFile(const CDiskBlockPos &pos, bool fReadOnly) { + return OpenDiskFile(pos, "rev", fReadOnly); +} + +fs::path GetBlockPosFilename(const CDiskBlockPos &pos, const char *prefix) +{ + return GetBlocksDir() / strprintf("%s%05u.dat", prefix, pos.nFile); +} + +CBlockIndex * CChainState::InsertBlockIndex(const uint256& hash) +{ + AssertLockHeld(cs_main); + + if (hash.IsNull()) + return nullptr; + + // Return existing + BlockMap::iterator mi = mapBlockIndex.find(hash); + if (mi != mapBlockIndex.end()) + return (*mi).second; + + // Create new + CBlockIndex* pindexNew = new CBlockIndex(); + mi = mapBlockIndex.insert(std::make_pair(hash, pindexNew)).first; + pindexNew->phashBlock = &((*mi).first); + + return pindexNew; +} + +bool CChainState::LoadBlockIndex(const Consensus::Params& consensus_params, CBlockTreeDB& blocktree) +{ + if (!blocktree.LoadBlockIndexGuts(consensus_params, [this](const uint256& hash) EXCLUSIVE_LOCKS_REQUIRED(cs_main) { return this->InsertBlockIndex(hash); })) + return false; + + boost::this_thread::interruption_point(); + + // Calculate nChainWork + std::vector<std::pair<int, CBlockIndex*> > vSortedByHeight; + vSortedByHeight.reserve(mapBlockIndex.size()); + for (const std::pair<const uint256, CBlockIndex*>& item : mapBlockIndex) + { + CBlockIndex* pindex = item.second; + vSortedByHeight.push_back(std::make_pair(pindex->nHeight, pindex)); + } + sort(vSortedByHeight.begin(), vSortedByHeight.end()); + for (const std::pair<int, CBlockIndex*>& item : vSortedByHeight) + { + 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) { + if (pindex->pprev) { + if (pindex->pprev->nChainTx) { + pindex->nChainTx = pindex->pprev->nChainTx + pindex->nTx; + } else { + pindex->nChainTx = 0; + mapBlocksUnlinked.insert(std::make_pair(pindex->pprev, pindex)); + } + } else { + pindex->nChainTx = pindex->nTx; + } + } + if (!(pindex->nStatus & BLOCK_FAILED_MASK) && pindex->pprev && (pindex->pprev->nStatus & BLOCK_FAILED_MASK)) { + pindex->nStatus |= BLOCK_FAILED_CHILD; + setDirtyBlockIndex.insert(pindex); + } + if (pindex->IsValid(BLOCK_VALID_TRANSACTIONS) && (pindex->nChainTx || pindex->pprev == nullptr)) + setBlockIndexCandidates.insert(pindex); + if (pindex->nStatus & BLOCK_FAILED_MASK && (!pindexBestInvalid || pindex->nChainWork > pindexBestInvalid->nChainWork)) + pindexBestInvalid = pindex; + if (pindex->pprev) + pindex->BuildSkip(); + if (pindex->IsValid(BLOCK_VALID_TREE) && (pindexBestHeader == nullptr || CBlockIndexWorkComparator()(pindexBestHeader, pindex))) + pindexBestHeader = pindex; + } + + return true; +} + +bool static LoadBlockIndexDB(const CChainParams& chainparams) EXCLUSIVE_LOCKS_REQUIRED(cs_main) +{ + if (!g_chainstate.LoadBlockIndex(chainparams.GetConsensus(), *pblocktree)) + return false; + + // Load block file info + pblocktree->ReadLastBlockFile(nLastBlockFile); + vinfoBlockFile.resize(nLastBlockFile + 1); + LogPrintf("%s: last block file = %i\n", __func__, nLastBlockFile); + for (int nFile = 0; nFile <= nLastBlockFile; nFile++) { + pblocktree->ReadBlockFileInfo(nFile, vinfoBlockFile[nFile]); + } + LogPrintf("%s: last block file info: %s\n", __func__, vinfoBlockFile[nLastBlockFile].ToString()); + for (int nFile = nLastBlockFile + 1; true; nFile++) { + CBlockFileInfo info; + if (pblocktree->ReadBlockFileInfo(nFile, info)) { + vinfoBlockFile.push_back(info); + } else { + break; + } + } + + // Check presence of blk files + LogPrintf("Checking all blk files are present...\n"); + std::set<int> setBlkDataFiles; + for (const std::pair<const uint256, CBlockIndex*>& item : mapBlockIndex) + { + CBlockIndex* pindex = item.second; + if (pindex->nStatus & BLOCK_HAVE_DATA) { + setBlkDataFiles.insert(pindex->nFile); + } + } + for (std::set<int>::iterator it = setBlkDataFiles.begin(); it != setBlkDataFiles.end(); it++) + { + CDiskBlockPos pos(*it, 0); + if (CAutoFile(OpenBlockFile(pos, true), SER_DISK, CLIENT_VERSION).IsNull()) { + return false; + } + } + + // Check whether we have ever pruned block & undo files + pblocktree->ReadFlag("prunedblockfiles", fHavePruned); + if (fHavePruned) + LogPrintf("LoadBlockIndexDB(): Block files have previously been pruned\n"); + + // Check whether we need to continue reindexing + bool fReindexing = false; + pblocktree->ReadReindexing(fReindexing); + if(fReindexing) fReindex = true; + + return true; +} + +bool LoadChainTip(const CChainParams& chainparams) +{ + AssertLockHeld(cs_main); + + if (chainActive.Tip() && chainActive.Tip()->GetBlockHash() == pcoinsTip->GetBestBlock()) return true; + + if (pcoinsTip->GetBestBlock().IsNull() && mapBlockIndex.size() == 1) { + // In case we just added the genesis block, connect it now, so + // that we always have a chainActive.Tip() when we return. + LogPrintf("%s: Connecting genesis block...\n", __func__); + CValidationState state; + if (!ActivateBestChain(state, chainparams)) { + LogPrintf("%s: failed to activate chain (%s)\n", __func__, FormatStateMessage(state)); + return false; + } + } + + // Load pointer to end of best chain + CBlockIndex* pindex = LookupBlockIndex(pcoinsTip->GetBestBlock()); + if (!pindex) { + return false; + } + chainActive.SetTip(pindex); + + g_chainstate.PruneBlockIndexCandidates(); + + LogPrintf("Loaded best chain: hashBestChain=%s height=%d date=%s progress=%f\n", + chainActive.Tip()->GetBlockHash().ToString(), chainActive.Height(), + FormatISO8601DateTime(chainActive.Tip()->GetBlockTime()), + GuessVerificationProgress(chainparams.TxData(), chainActive.Tip())); + return true; +} + +CVerifyDB::CVerifyDB() +{ + uiInterface.ShowProgress(_("Verifying blocks..."), 0, false); +} + +CVerifyDB::~CVerifyDB() +{ + uiInterface.ShowProgress("", 100, false); +} + +bool CVerifyDB::VerifyDB(const CChainParams& chainparams, CCoinsView *coinsview, int nCheckLevel, int nCheckDepth) +{ + LOCK(cs_main); + if (chainActive.Tip() == nullptr || chainActive.Tip()->pprev == nullptr) + return true; + + // Verify blocks in the best chain + if (nCheckDepth <= 0 || nCheckDepth > chainActive.Height()) + nCheckDepth = chainActive.Height(); + nCheckLevel = std::max(0, std::min(4, nCheckLevel)); + LogPrintf("Verifying last %i blocks at level %i\n", nCheckDepth, nCheckLevel); + CCoinsViewCache coins(coinsview); + CBlockIndex* pindex; + CBlockIndex* pindexFailure = nullptr; + int nGoodTransactions = 0; + CValidationState state; + int reportDone = 0; + LogPrintf("[0%%]..."); /* Continued */ + for (pindex = chainActive.Tip(); pindex && pindex->pprev; pindex = pindex->pprev) { + boost::this_thread::interruption_point(); + int percentageDone = std::max(1, std::min(99, (int)(((double)(chainActive.Height() - pindex->nHeight)) / (double)nCheckDepth * (nCheckLevel >= 4 ? 50 : 100)))); + if (reportDone < percentageDone/10) { + // report every 10% step + LogPrintf("[%d%%]...", percentageDone); /* Continued */ + reportDone = percentageDone/10; + } + uiInterface.ShowProgress(_("Verifying blocks..."), percentageDone, false); + if (pindex->nHeight <= chainActive.Height()-nCheckDepth) + break; + if (fPruneMode && !(pindex->nStatus & BLOCK_HAVE_DATA)) { + // If pruning, only go back as far as we have data. + LogPrintf("VerifyDB(): block verification stopping at height %d (pruning, no data)\n", pindex->nHeight); + break; + } + CBlock block; + // check level 0: read from disk + if (!ReadBlockFromDisk(block, pindex, chainparams.GetConsensus())) + return error("VerifyDB(): *** ReadBlockFromDisk failed at %d, hash=%s", pindex->nHeight, pindex->GetBlockHash().ToString()); + // check level 1: verify block validity + if (nCheckLevel >= 1 && !CheckBlock(block, state, chainparams.GetConsensus())) + return error("%s: *** found bad block at %d, hash=%s (%s)\n", __func__, + pindex->nHeight, pindex->GetBlockHash().ToString(), FormatStateMessage(state)); + // check level 2: verify undo validity + if (nCheckLevel >= 2 && pindex) { + CBlockUndo undo; + if (!pindex->GetUndoPos().IsNull()) { + if (!UndoReadFromDisk(undo, pindex)) { + return error("VerifyDB(): *** found bad undo data at %d, hash=%s\n", pindex->nHeight, pindex->GetBlockHash().ToString()); + } + } + } + // check level 3: check for inconsistencies during memory-only disconnect of tip blocks + if (nCheckLevel >= 3 && (coins.DynamicMemoryUsage() + pcoinsTip->DynamicMemoryUsage()) <= nCoinCacheUsage) { + assert(coins.GetBestBlock() == pindex->GetBlockHash()); + DisconnectResult res = g_chainstate.DisconnectBlock(block, pindex, coins); + if (res == DISCONNECT_FAILED) { + return error("VerifyDB(): *** irrecoverable inconsistency in block data at %d, hash=%s", pindex->nHeight, pindex->GetBlockHash().ToString()); + } + if (res == DISCONNECT_UNCLEAN) { + nGoodTransactions = 0; + pindexFailure = pindex; + } else { + nGoodTransactions += block.vtx.size(); + } + } + if (ShutdownRequested()) + return true; + } + if (pindexFailure) + return error("VerifyDB(): *** coin database inconsistencies found (last %i blocks, %i good transactions before that)\n", chainActive.Height() - pindexFailure->nHeight + 1, nGoodTransactions); + + // store block count as we move pindex at check level >= 4 + int block_count = chainActive.Height() - pindex->nHeight; + + // check level 4: try reconnecting blocks + if (nCheckLevel >= 4) { + while (pindex != chainActive.Tip()) { + boost::this_thread::interruption_point(); + uiInterface.ShowProgress(_("Verifying blocks..."), std::max(1, std::min(99, 100 - (int)(((double)(chainActive.Height() - pindex->nHeight)) / (double)nCheckDepth * 50))), false); + pindex = chainActive.Next(pindex); + CBlock block; + if (!ReadBlockFromDisk(block, pindex, chainparams.GetConsensus())) + return error("VerifyDB(): *** ReadBlockFromDisk failed at %d, hash=%s", pindex->nHeight, pindex->GetBlockHash().ToString()); + if (!g_chainstate.ConnectBlock(block, state, pindex, coins, chainparams)) + return error("VerifyDB(): *** found unconnectable block at %d, hash=%s (%s)", pindex->nHeight, pindex->GetBlockHash().ToString(), FormatStateMessage(state)); + } + } + + LogPrintf("[DONE].\n"); + LogPrintf("No coin database inconsistencies in last %i blocks (%i transactions)\n", block_count, nGoodTransactions); + + return true; +} + +/** Apply the effects of a block on the utxo cache, ignoring that it may already have been applied. */ +bool CChainState::RollforwardBlock(const CBlockIndex* pindex, CCoinsViewCache& inputs, const CChainParams& params) +{ + // TODO: merge with ConnectBlock + CBlock block; + if (!ReadBlockFromDisk(block, pindex, params.GetConsensus())) { + return error("ReplayBlock(): ReadBlockFromDisk failed at %d, hash=%s", pindex->nHeight, pindex->GetBlockHash().ToString()); + } + + for (const CTransactionRef& tx : block.vtx) { + if (!tx->IsCoinBase()) { + for (const CTxIn &txin : tx->vin) { + inputs.SpendCoin(txin.prevout); + } + } + // Pass check = true as every addition may be an overwrite. + AddCoins(inputs, *tx, pindex->nHeight, true); + } + return true; +} + +bool CChainState::ReplayBlocks(const CChainParams& params, CCoinsView* view) +{ + LOCK(cs_main); + + CCoinsViewCache cache(view); + + std::vector<uint256> hashHeads = view->GetHeadBlocks(); + if (hashHeads.empty()) return true; // We're already in a consistent state. + if (hashHeads.size() != 2) return error("ReplayBlocks(): unknown inconsistent state"); + + uiInterface.ShowProgress(_("Replaying blocks..."), 0, false); + LogPrintf("Replaying blocks\n"); + + const CBlockIndex* pindexOld = nullptr; // Old tip during the interrupted flush. + const CBlockIndex* pindexNew; // New tip during the interrupted flush. + const CBlockIndex* pindexFork = nullptr; // Latest block common to both the old and the new tip. + + if (mapBlockIndex.count(hashHeads[0]) == 0) { + return error("ReplayBlocks(): reorganization to unknown block requested"); + } + pindexNew = mapBlockIndex[hashHeads[0]]; + + if (!hashHeads[1].IsNull()) { // The old tip is allowed to be 0, indicating it's the first flush. + if (mapBlockIndex.count(hashHeads[1]) == 0) { + return error("ReplayBlocks(): reorganization from unknown block requested"); + } + pindexOld = mapBlockIndex[hashHeads[1]]; + pindexFork = LastCommonAncestor(pindexOld, pindexNew); + assert(pindexFork != nullptr); + } + + // Rollback along the old branch. + while (pindexOld != pindexFork) { + if (pindexOld->nHeight > 0) { // Never disconnect the genesis block. + CBlock block; + if (!ReadBlockFromDisk(block, pindexOld, params.GetConsensus())) { + return error("RollbackBlock(): ReadBlockFromDisk() failed at %d, hash=%s", pindexOld->nHeight, pindexOld->GetBlockHash().ToString()); + } + LogPrintf("Rolling back %s (%i)\n", pindexOld->GetBlockHash().ToString(), pindexOld->nHeight); + DisconnectResult res = DisconnectBlock(block, pindexOld, cache); + if (res == DISCONNECT_FAILED) { + return error("RollbackBlock(): DisconnectBlock failed at %d, hash=%s", pindexOld->nHeight, pindexOld->GetBlockHash().ToString()); + } + // If DISCONNECT_UNCLEAN is returned, it means a non-existing UTXO was deleted, or an existing UTXO was + // overwritten. It corresponds to cases where the block-to-be-disconnect never had all its operations + // applied to the UTXO set. However, as both writing a UTXO and deleting a UTXO are idempotent operations, + // the result is still a version of the UTXO set with the effects of that block undone. + } + pindexOld = pindexOld->pprev; + } + + // Roll forward from the forking point to the new tip. + int nForkHeight = pindexFork ? pindexFork->nHeight : 0; + for (int nHeight = nForkHeight + 1; nHeight <= pindexNew->nHeight; ++nHeight) { + const CBlockIndex* pindex = pindexNew->GetAncestor(nHeight); + LogPrintf("Rolling forward %s (%i)\n", pindex->GetBlockHash().ToString(), nHeight); + if (!RollforwardBlock(pindex, cache, params)) return false; + } + + cache.SetBestBlock(pindexNew->GetBlockHash()); + cache.Flush(); + uiInterface.ShowProgress("", 100, false); + return true; +} + +bool ReplayBlocks(const CChainParams& params, CCoinsView* view) { + return g_chainstate.ReplayBlocks(params, view); +} + +bool CChainState::RewindBlockIndex(const CChainParams& params) +{ + LOCK(cs_main); + + // Note that during -reindex-chainstate we are called with an empty chainActive! + + int nHeight = 1; + while (nHeight <= chainActive.Height()) { + // Although SCRIPT_VERIFY_WITNESS is now generally enforced on all + // blocks in ConnectBlock, we don't need to go back and + // re-download/re-verify blocks from before segwit actually activated. + if (IsWitnessEnabled(chainActive[nHeight - 1], params.GetConsensus()) && !(chainActive[nHeight]->nStatus & BLOCK_OPT_WITNESS)) { + break; + } + nHeight++; + } + + // nHeight is now the height of the first insufficiently-validated block, or tipheight + 1 + CValidationState state; + CBlockIndex* pindex = chainActive.Tip(); + while (chainActive.Height() >= nHeight) { + if (fPruneMode && !(chainActive.Tip()->nStatus & BLOCK_HAVE_DATA)) { + // If pruning, don't try rewinding past the HAVE_DATA point; + // since older blocks can't be served anyway, there's + // no need to walk further, and trying to DisconnectTip() + // will fail (and require a needless reindex/redownload + // of the blockchain). + break; + } + if (!DisconnectTip(state, params, nullptr)) { + return error("RewindBlockIndex: unable to disconnect block at height %i (%s)", pindex->nHeight, FormatStateMessage(state)); + } + // Occasionally flush state to disk. + if (!FlushStateToDisk(params, state, FlushStateMode::PERIODIC)) { + LogPrintf("RewindBlockIndex: unable to flush state to disk (%s)\n", FormatStateMessage(state)); + return false; + } + } + + // Reduce validity flag and have-data flags. + // We do this after actual disconnecting, otherwise we'll end up writing the lack of data + // to disk before writing the chainstate, resulting in a failure to continue if interrupted. + for (const auto& entry : mapBlockIndex) { + CBlockIndex* pindexIter = entry.second; + + // Note: If we encounter an insufficiently validated block that + // is on chainActive, it must be because we are a pruning node, and + // this block or some successor doesn't HAVE_DATA, so we were unable to + // rewind all the way. Blocks remaining on chainActive at this point + // must not have their validity reduced. + if (IsWitnessEnabled(pindexIter->pprev, params.GetConsensus()) && !(pindexIter->nStatus & BLOCK_OPT_WITNESS) && !chainActive.Contains(pindexIter)) { + // Reduce validity + pindexIter->nStatus = std::min<unsigned int>(pindexIter->nStatus & BLOCK_VALID_MASK, BLOCK_VALID_TREE) | (pindexIter->nStatus & ~BLOCK_VALID_MASK); + // Remove have-data flags. + pindexIter->nStatus &= ~(BLOCK_HAVE_DATA | BLOCK_HAVE_UNDO); + // Remove storage location. + pindexIter->nFile = 0; + pindexIter->nDataPos = 0; + pindexIter->nUndoPos = 0; + // Remove various other things + pindexIter->nTx = 0; + pindexIter->nChainTx = 0; + pindexIter->nSequenceId = 0; + // Make sure it gets written. + setDirtyBlockIndex.insert(pindexIter); + // Update indexes + setBlockIndexCandidates.erase(pindexIter); + std::pair<std::multimap<CBlockIndex*, CBlockIndex*>::iterator, std::multimap<CBlockIndex*, CBlockIndex*>::iterator> ret = mapBlocksUnlinked.equal_range(pindexIter->pprev); + while (ret.first != ret.second) { + if (ret.first->second == pindexIter) { + mapBlocksUnlinked.erase(ret.first++); + } else { + ++ret.first; + } + } + } else if (pindexIter->IsValid(BLOCK_VALID_TRANSACTIONS) && pindexIter->nChainTx) { + setBlockIndexCandidates.insert(pindexIter); + } + } + + if (chainActive.Tip() != nullptr) { + // We can't prune block index candidates based on our tip if we have + // no tip due to chainActive being empty! + PruneBlockIndexCandidates(); + + CheckBlockIndex(params.GetConsensus()); + } + + return true; +} + +bool RewindBlockIndex(const CChainParams& params) { + if (!g_chainstate.RewindBlockIndex(params)) { + return false; + } + + if (chainActive.Tip() != nullptr) { + // FlushStateToDisk can possibly read chainActive. Be conservative + // and skip it here, we're about to -reindex-chainstate anyway, so + // it'll get called a bunch real soon. + CValidationState state; + if (!FlushStateToDisk(params, state, FlushStateMode::ALWAYS)) { + LogPrintf("RewindBlockIndex: unable to flush state to disk (%s)\n", FormatStateMessage(state)); + return false; + } + } + + return true; +} + +void CChainState::UnloadBlockIndex() { + nBlockSequenceId = 1; + m_failed_blocks.clear(); + setBlockIndexCandidates.clear(); +} + +// May NOT be used after any connections are up as much +// of the peer-processing logic assumes a consistent +// block index state +void UnloadBlockIndex() +{ + LOCK(cs_main); + chainActive.SetTip(nullptr); + pindexBestInvalid = nullptr; + pindexBestHeader = nullptr; + mempool.clear(); + mapBlocksUnlinked.clear(); + vinfoBlockFile.clear(); + nLastBlockFile = 0; + setDirtyBlockIndex.clear(); + setDirtyFileInfo.clear(); + versionbitscache.Clear(); + for (int b = 0; b < VERSIONBITS_NUM_BITS; b++) { + warningcache[b].clear(); + } + + for (BlockMap::value_type& entry : mapBlockIndex) { + delete entry.second; + } + mapBlockIndex.clear(); + fHavePruned = false; + + g_chainstate.UnloadBlockIndex(); +} + +bool LoadBlockIndex(const CChainParams& chainparams) +{ + // Load block index from databases + bool needs_init = fReindex; + if (!fReindex) { + bool ret = LoadBlockIndexDB(chainparams); + if (!ret) return false; + needs_init = mapBlockIndex.empty(); + } + + if (needs_init) { + // Everything here is for *new* reindex/DBs. Thus, though + // LoadBlockIndexDB may have set fReindex if we shut down + // mid-reindex previously, we don't check fReindex and + // instead only check it prior to LoadBlockIndexDB to set + // needs_init. + + LogPrintf("Initializing databases...\n"); + } + return true; +} + +bool CChainState::LoadGenesisBlock(const CChainParams& chainparams) +{ + LOCK(cs_main); + + // Check whether we're already initialized by checking for genesis in + // mapBlockIndex. Note that we can't use chainActive here, since it is + // set based on the coins db, not the block index db, which is the only + // thing loaded at this point. + if (mapBlockIndex.count(chainparams.GenesisBlock().GetHash())) + return true; + + try { + CBlock &block = const_cast<CBlock&>(chainparams.GenesisBlock()); + CDiskBlockPos blockPos = SaveBlockToDisk(block, 0, chainparams, nullptr); + if (blockPos.IsNull()) + return error("%s: writing genesis block to disk failed", __func__); + CBlockIndex *pindex = AddToBlockIndex(block); + ReceivedBlockTransactions(block, pindex, blockPos, chainparams.GetConsensus()); + } catch (const std::runtime_error& e) { + return error("%s: failed to write genesis block: %s", __func__, e.what()); + } + + return true; +} + +bool LoadGenesisBlock(const CChainParams& chainparams) +{ + return g_chainstate.LoadGenesisBlock(chainparams); +} + +bool LoadExternalBlockFile(const CChainParams& chainparams, FILE* fileIn, CDiskBlockPos *dbp) +{ + // Map of disk positions for blocks with unknown parent (only used for reindex) + static std::multimap<uint256, CDiskBlockPos> mapBlocksUnknownParent; + int64_t nStart = GetTimeMillis(); + + int nLoaded = 0; + try { + // This takes over fileIn and calls fclose() on it in the CBufferedFile destructor + CBufferedFile blkdat(fileIn, 2*MAX_BLOCK_SERIALIZED_SIZE, MAX_BLOCK_SERIALIZED_SIZE+8, SER_DISK, CLIENT_VERSION); + uint64_t nRewind = blkdat.GetPos(); + while (!blkdat.eof()) { + boost::this_thread::interruption_point(); + + blkdat.SetPos(nRewind); + nRewind++; // start one byte further next time, in case of failure + blkdat.SetLimit(); // remove former limit + unsigned int nSize = 0; + try { + // locate a header + unsigned char buf[CMessageHeader::MESSAGE_START_SIZE]; + blkdat.FindByte(chainparams.MessageStart()[0]); + nRewind = blkdat.GetPos()+1; + blkdat >> buf; + if (memcmp(buf, chainparams.MessageStart(), CMessageHeader::MESSAGE_START_SIZE)) + continue; + // read size + blkdat >> nSize; + if (nSize < 80 || nSize > MAX_BLOCK_SERIALIZED_SIZE) + continue; + } catch (const std::exception&) { + // no valid block header found; don't complain + break; + } + try { + // read block + uint64_t nBlockPos = blkdat.GetPos(); + if (dbp) + dbp->nPos = nBlockPos; + blkdat.SetLimit(nBlockPos + nSize); + blkdat.SetPos(nBlockPos); + std::shared_ptr<CBlock> pblock = std::make_shared<CBlock>(); + CBlock& block = *pblock; + blkdat >> block; + nRewind = blkdat.GetPos(); + + uint256 hash = block.GetHash(); + { + LOCK(cs_main); + // detect out of order blocks, and store them for later + if (hash != chainparams.GetConsensus().hashGenesisBlock && !LookupBlockIndex(block.hashPrevBlock)) { + LogPrint(BCLog::REINDEX, "%s: Out of order block %s, parent %s not known\n", __func__, hash.ToString(), + block.hashPrevBlock.ToString()); + if (dbp) + mapBlocksUnknownParent.insert(std::make_pair(block.hashPrevBlock, *dbp)); + continue; + } + + // process in case the block isn't known yet + CBlockIndex* pindex = LookupBlockIndex(hash); + if (!pindex || (pindex->nStatus & BLOCK_HAVE_DATA) == 0) { + CValidationState state; + if (g_chainstate.AcceptBlock(pblock, state, chainparams, nullptr, true, dbp, nullptr)) { + nLoaded++; + } + if (state.IsError()) { + break; + } + } else if (hash != chainparams.GetConsensus().hashGenesisBlock && pindex->nHeight % 1000 == 0) { + LogPrint(BCLog::REINDEX, "Block Import: already had block %s at height %d\n", hash.ToString(), pindex->nHeight); + } + } + + // Activate the genesis block so normal node progress can continue + if (hash == chainparams.GetConsensus().hashGenesisBlock) { + CValidationState state; + if (!ActivateBestChain(state, chainparams)) { + break; + } + } + + NotifyHeaderTip(); + + // Recursively process earlier encountered successors of this block + std::deque<uint256> queue; + queue.push_back(hash); + while (!queue.empty()) { + uint256 head = queue.front(); + queue.pop_front(); + 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; + std::shared_ptr<CBlock> pblockrecursive = std::make_shared<CBlock>(); + if (ReadBlockFromDisk(*pblockrecursive, it->second, chainparams.GetConsensus())) + { + LogPrint(BCLog::REINDEX, "%s: Processing out of order child %s of %s\n", __func__, pblockrecursive->GetHash().ToString(), + head.ToString()); + LOCK(cs_main); + CValidationState dummy; + if (g_chainstate.AcceptBlock(pblockrecursive, dummy, chainparams, nullptr, true, &it->second, nullptr)) + { + nLoaded++; + queue.push_back(pblockrecursive->GetHash()); + } + } + range.first++; + mapBlocksUnknownParent.erase(it); + NotifyHeaderTip(); + } + } + } catch (const std::exception& e) { + LogPrintf("%s: Deserialize or I/O error - %s\n", __func__, e.what()); + } + } + } catch (const std::runtime_error& e) { + AbortNode(std::string("System error: ") + e.what()); + } + if (nLoaded > 0) + LogPrintf("Loaded %i blocks from external file in %dms\n", nLoaded, GetTimeMillis() - nStart); + return nLoaded > 0; +} + +void CChainState::CheckBlockIndex(const Consensus::Params& consensusParams) +{ + if (!fCheckBlockIndex) { + return; + } + + LOCK(cs_main); + + // During a reindex, we read the genesis block and call CheckBlockIndex before ActivateBestChain, + // so we have the genesis block in mapBlockIndex but no active chain. (A few of the tests when + // iterating the block tree require that chainActive has been initialized.) + if (chainActive.Height() < 0) { + assert(mapBlockIndex.size() <= 1); + return; + } + + // Build forward-pointing map of the entire block tree. + std::multimap<CBlockIndex*,CBlockIndex*> forward; + for (auto& entry : mapBlockIndex) { + forward.insert(std::make_pair(entry.second->pprev, entry.second)); + } + + assert(forward.size() == mapBlockIndex.size()); + + std::pair<std::multimap<CBlockIndex*,CBlockIndex*>::iterator,std::multimap<CBlockIndex*,CBlockIndex*>::iterator> rangeGenesis = forward.equal_range(nullptr); + CBlockIndex *pindex = rangeGenesis.first->second; + rangeGenesis.first++; + assert(rangeGenesis.first == rangeGenesis.second); // There is only one index entry with parent nullptr. + + // Iterate over the entire block tree, using depth-first search. + // Along the way, remember whether there are blocks on the path from genesis + // block being explored which are the first to have certain properties. + size_t nNodes = 0; + int nHeight = 0; + CBlockIndex* pindexFirstInvalid = nullptr; // Oldest ancestor of pindex which is invalid. + CBlockIndex* pindexFirstMissing = nullptr; // Oldest ancestor of pindex which does not have BLOCK_HAVE_DATA. + CBlockIndex* pindexFirstNeverProcessed = nullptr; // Oldest ancestor of pindex for which nTx == 0. + CBlockIndex* pindexFirstNotTreeValid = nullptr; // Oldest ancestor of pindex which does not have BLOCK_VALID_TREE (regardless of being valid or not). + CBlockIndex* pindexFirstNotTransactionsValid = nullptr; // Oldest ancestor of pindex which does not have BLOCK_VALID_TRANSACTIONS (regardless of being valid or not). + CBlockIndex* pindexFirstNotChainValid = nullptr; // Oldest ancestor of pindex which does not have BLOCK_VALID_CHAIN (regardless of being valid or not). + CBlockIndex* pindexFirstNotScriptsValid = nullptr; // Oldest ancestor of pindex which does not have BLOCK_VALID_SCRIPTS (regardless of being valid or not). + while (pindex != nullptr) { + nNodes++; + if (pindexFirstInvalid == nullptr && pindex->nStatus & BLOCK_FAILED_VALID) pindexFirstInvalid = pindex; + if (pindexFirstMissing == nullptr && !(pindex->nStatus & BLOCK_HAVE_DATA)) pindexFirstMissing = pindex; + if (pindexFirstNeverProcessed == nullptr && pindex->nTx == 0) pindexFirstNeverProcessed = pindex; + if (pindex->pprev != nullptr && pindexFirstNotTreeValid == nullptr && (pindex->nStatus & BLOCK_VALID_MASK) < BLOCK_VALID_TREE) pindexFirstNotTreeValid = pindex; + if (pindex->pprev != nullptr && pindexFirstNotTransactionsValid == nullptr && (pindex->nStatus & BLOCK_VALID_MASK) < BLOCK_VALID_TRANSACTIONS) pindexFirstNotTransactionsValid = pindex; + if (pindex->pprev != nullptr && pindexFirstNotChainValid == nullptr && (pindex->nStatus & BLOCK_VALID_MASK) < BLOCK_VALID_CHAIN) pindexFirstNotChainValid = pindex; + if (pindex->pprev != nullptr && pindexFirstNotScriptsValid == nullptr && (pindex->nStatus & BLOCK_VALID_MASK) < BLOCK_VALID_SCRIPTS) pindexFirstNotScriptsValid = pindex; + + // Begin: actual consistency checks. + if (pindex->pprev == nullptr) { + // Genesis block checks. + assert(pindex->GetBlockHash() == consensusParams.hashGenesisBlock); // Genesis block's hash must match. + assert(pindex == chainActive.Genesis()); // The current active chain's genesis block must be this block. + } + if (pindex->nChainTx == 0) assert(pindex->nSequenceId <= 0); // nSequenceId can't be set positive for blocks that aren't linked (negative is used for preciousblock) + // VALID_TRANSACTIONS is equivalent to nTx > 0 for all nodes (whether or not pruning has occurred). + // HAVE_DATA is only equivalent to nTx > 0 (or VALID_TRANSACTIONS) if no pruning has occurred. + if (!fHavePruned) { + // If we've never pruned, then HAVE_DATA should be equivalent to nTx > 0 + assert(!(pindex->nStatus & BLOCK_HAVE_DATA) == (pindex->nTx == 0)); + assert(pindexFirstMissing == pindexFirstNeverProcessed); + } else { + // If we have pruned, then we can only say that HAVE_DATA implies nTx > 0 + if (pindex->nStatus & BLOCK_HAVE_DATA) assert(pindex->nTx > 0); + } + if (pindex->nStatus & BLOCK_HAVE_UNDO) assert(pindex->nStatus & BLOCK_HAVE_DATA); + assert(((pindex->nStatus & BLOCK_VALID_MASK) >= BLOCK_VALID_TRANSACTIONS) == (pindex->nTx > 0)); // This is pruning-independent. + // All parents having had data (at some point) is equivalent to all parents being VALID_TRANSACTIONS, which is equivalent to nChainTx being set. + assert((pindexFirstNeverProcessed != nullptr) == (pindex->nChainTx == 0)); // nChainTx != 0 is used to signal that all parent blocks have been processed (but may have been pruned). + assert((pindexFirstNotTransactionsValid != nullptr) == (pindex->nChainTx == 0)); + assert(pindex->nHeight == nHeight); // nHeight must be consistent. + assert(pindex->pprev == nullptr || pindex->nChainWork >= pindex->pprev->nChainWork); // For every block except the genesis block, the chainwork must be larger than the parent's. + assert(nHeight < 2 || (pindex->pskip && (pindex->pskip->nHeight < nHeight))); // The pskip pointer must point back for all but the first 2 blocks. + assert(pindexFirstNotTreeValid == nullptr); // All mapBlockIndex entries must at least be TREE valid + if ((pindex->nStatus & BLOCK_VALID_MASK) >= BLOCK_VALID_TREE) assert(pindexFirstNotTreeValid == nullptr); // TREE valid implies all parents are TREE valid + if ((pindex->nStatus & BLOCK_VALID_MASK) >= BLOCK_VALID_CHAIN) assert(pindexFirstNotChainValid == nullptr); // CHAIN valid implies all parents are CHAIN valid + if ((pindex->nStatus & BLOCK_VALID_MASK) >= BLOCK_VALID_SCRIPTS) assert(pindexFirstNotScriptsValid == nullptr); // SCRIPTS valid implies all parents are SCRIPTS valid + if (pindexFirstInvalid == nullptr) { + // Checks for not-invalid blocks. + assert((pindex->nStatus & BLOCK_FAILED_MASK) == 0); // The failed mask cannot be set for blocks without invalid parents. + } + if (!CBlockIndexWorkComparator()(pindex, chainActive.Tip()) && pindexFirstNeverProcessed == nullptr) { + if (pindexFirstInvalid == nullptr) { + // If this block sorts at least as good as the current tip and + // is valid and we have all data for its parents, it must be in + // setBlockIndexCandidates. chainActive.Tip() must also be there + // even if some data has been pruned. + if (pindexFirstMissing == nullptr || pindex == chainActive.Tip()) { + assert(setBlockIndexCandidates.count(pindex)); + } + // If some parent is missing, then it could be that this block was in + // setBlockIndexCandidates but had to be removed because of the missing data. + // In this case it must be in mapBlocksUnlinked -- see test below. + } + } else { // If this block sorts worse than the current tip or some ancestor's block has never been seen, it cannot be in setBlockIndexCandidates. + assert(setBlockIndexCandidates.count(pindex) == 0); + } + // Check whether this block is in mapBlocksUnlinked. + std::pair<std::multimap<CBlockIndex*,CBlockIndex*>::iterator,std::multimap<CBlockIndex*,CBlockIndex*>::iterator> rangeUnlinked = mapBlocksUnlinked.equal_range(pindex->pprev); + bool foundInUnlinked = false; + while (rangeUnlinked.first != rangeUnlinked.second) { + assert(rangeUnlinked.first->first == pindex->pprev); + if (rangeUnlinked.first->second == pindex) { + foundInUnlinked = true; + break; + } + rangeUnlinked.first++; + } + if (pindex->pprev && (pindex->nStatus & BLOCK_HAVE_DATA) && pindexFirstNeverProcessed != nullptr && pindexFirstInvalid == nullptr) { + // If this block has block data available, some parent was never received, and has no invalid parents, it must be in mapBlocksUnlinked. + assert(foundInUnlinked); + } + if (!(pindex->nStatus & BLOCK_HAVE_DATA)) assert(!foundInUnlinked); // Can't be in mapBlocksUnlinked if we don't HAVE_DATA + if (pindexFirstMissing == nullptr) assert(!foundInUnlinked); // We aren't missing data for any parent -- cannot be in mapBlocksUnlinked. + if (pindex->pprev && (pindex->nStatus & BLOCK_HAVE_DATA) && pindexFirstNeverProcessed == nullptr && pindexFirstMissing != nullptr) { + // We HAVE_DATA for this block, have received data for all parents at some point, but we're currently missing data for some parent. + assert(fHavePruned); // We must have pruned. + // This block may have entered mapBlocksUnlinked if: + // - it has a descendant that at some point had more work than the + // tip, and + // - we tried switching to that descendant but were missing + // data for some intermediate block between chainActive and the + // tip. + // So if this block is itself better than chainActive.Tip() and it wasn't in + // setBlockIndexCandidates, then it must be in mapBlocksUnlinked. + if (!CBlockIndexWorkComparator()(pindex, chainActive.Tip()) && setBlockIndexCandidates.count(pindex) == 0) { + if (pindexFirstInvalid == nullptr) { + assert(foundInUnlinked); + } + } + } + // assert(pindex->GetBlockHash() == pindex->GetBlockHeader().GetHash()); // Perhaps too slow + // End: actual consistency checks. + + // Try descending into the first subnode. + std::pair<std::multimap<CBlockIndex*,CBlockIndex*>::iterator,std::multimap<CBlockIndex*,CBlockIndex*>::iterator> range = forward.equal_range(pindex); + if (range.first != range.second) { + // A subnode was found. + pindex = range.first->second; + nHeight++; + continue; + } + // This is a leaf node. + // Move upwards until we reach a node of which we have not yet visited the last child. + while (pindex) { + // We are going to either move to a parent or a sibling of pindex. + // If pindex was the first with a certain property, unset the corresponding variable. + if (pindex == pindexFirstInvalid) pindexFirstInvalid = nullptr; + if (pindex == pindexFirstMissing) pindexFirstMissing = nullptr; + if (pindex == pindexFirstNeverProcessed) pindexFirstNeverProcessed = nullptr; + if (pindex == pindexFirstNotTreeValid) pindexFirstNotTreeValid = nullptr; + if (pindex == pindexFirstNotTransactionsValid) pindexFirstNotTransactionsValid = nullptr; + if (pindex == pindexFirstNotChainValid) pindexFirstNotChainValid = nullptr; + if (pindex == pindexFirstNotScriptsValid) pindexFirstNotScriptsValid = nullptr; + // Find our parent. + CBlockIndex* pindexPar = pindex->pprev; + // Find which child we just visited. + std::pair<std::multimap<CBlockIndex*,CBlockIndex*>::iterator,std::multimap<CBlockIndex*,CBlockIndex*>::iterator> rangePar = forward.equal_range(pindexPar); + while (rangePar.first->second != pindex) { + assert(rangePar.first != rangePar.second); // Our parent must have at least the node we're coming from as child. + rangePar.first++; + } + // Proceed to the next one. + rangePar.first++; + if (rangePar.first != rangePar.second) { + // Move to the sibling. + pindex = rangePar.first->second; + break; + } else { + // Move up further. + pindex = pindexPar; + nHeight--; + continue; + } + } + } + + // Check that we actually traversed the entire map. + assert(nNodes == forward.size()); +} + +std::string CBlockFileInfo::ToString() const +{ + return strprintf("CBlockFileInfo(blocks=%u, size=%u, heights=%u...%u, time=%s...%s)", nBlocks, nSize, nHeightFirst, nHeightLast, FormatISO8601Date(nTimeFirst), FormatISO8601Date(nTimeLast)); +} + +CBlockFileInfo* GetBlockFileInfo(size_t n) +{ + LOCK(cs_LastBlockFile); + + return &vinfoBlockFile.at(n); +} + +ThresholdState VersionBitsTipState(const Consensus::Params& params, Consensus::DeploymentPos pos) +{ + LOCK(cs_main); + return VersionBitsState(chainActive.Tip(), params, pos, versionbitscache); +} + +BIP9Stats VersionBitsTipStatistics(const Consensus::Params& params, Consensus::DeploymentPos pos) +{ + LOCK(cs_main); + return VersionBitsStatistics(chainActive.Tip(), params, pos); +} + +int VersionBitsTipStateSinceHeight(const Consensus::Params& params, Consensus::DeploymentPos pos) +{ + LOCK(cs_main); + return VersionBitsStateSinceHeight(chainActive.Tip(), params, pos, versionbitscache); +} + +static const uint64_t MEMPOOL_DUMP_VERSION = 1; + +bool LoadMempool(void) +{ + const CChainParams& chainparams = Params(); + int64_t nExpiryTimeout = gArgs.GetArg("-mempoolexpiry", DEFAULT_MEMPOOL_EXPIRY) * 60 * 60; + FILE* filestr = fsbridge::fopen(GetDataDir() / "mempool.dat", "rb"); + CAutoFile file(filestr, SER_DISK, CLIENT_VERSION); + if (file.IsNull()) { + LogPrintf("Failed to open mempool file from disk. Continuing anyway.\n"); + return false; + } + + int64_t count = 0; + int64_t expired = 0; + int64_t failed = 0; + int64_t already_there = 0; + int64_t nNow = GetTime(); + + try { + uint64_t version; + file >> version; + if (version != MEMPOOL_DUMP_VERSION) { + return false; + } + uint64_t num; + file >> num; + while (num--) { + CTransactionRef tx; + int64_t nTime; + int64_t nFeeDelta; + file >> tx; + file >> nTime; + file >> nFeeDelta; + + CAmount amountdelta = nFeeDelta; + if (amountdelta) { + mempool.PrioritiseTransaction(tx->GetHash(), amountdelta); + } + CValidationState state; + if (nTime + nExpiryTimeout > nNow) { + LOCK(cs_main); + AcceptToMemoryPoolWithTime(chainparams, mempool, state, tx, nullptr /* pfMissingInputs */, nTime, + nullptr /* plTxnReplaced */, false /* bypass_limits */, 0 /* nAbsurdFee */, + false /* test_accept */); + if (state.IsValid()) { + ++count; + } else { + // mempool may contain the transaction already, e.g. from + // wallet(s) having loaded it while we were processing + // mempool transactions; consider these as valid, instead of + // failed, but mark them as 'already there' + if (mempool.exists(tx->GetHash())) { + ++already_there; + } else { + ++failed; + } + } + } else { + ++expired; + } + if (ShutdownRequested()) + return false; + } + std::map<uint256, CAmount> mapDeltas; + file >> mapDeltas; + + for (const auto& i : mapDeltas) { + mempool.PrioritiseTransaction(i.first, i.second); + } + } catch (const std::exception& e) { + LogPrintf("Failed to deserialize mempool data on disk: %s. Continuing anyway.\n", e.what()); + return false; + } + + LogPrintf("Imported mempool transactions from disk: %i succeeded, %i failed, %i expired, %i already there\n", count, failed, expired, already_there); + return true; +} + +bool DumpMempool(void) +{ + int64_t start = GetTimeMicros(); + + std::map<uint256, CAmount> mapDeltas; + std::vector<TxMempoolInfo> vinfo; + + { + LOCK(mempool.cs); + for (const auto &i : mempool.mapDeltas) { + mapDeltas[i.first] = i.second; + } + vinfo = mempool.infoAll(); + } + + int64_t mid = GetTimeMicros(); + + try { + FILE* filestr = fsbridge::fopen(GetDataDir() / "mempool.dat.new", "wb"); + if (!filestr) { + return false; + } + + CAutoFile file(filestr, SER_DISK, CLIENT_VERSION); + + uint64_t version = MEMPOOL_DUMP_VERSION; + file << version; + + file << (uint64_t)vinfo.size(); + for (const auto& i : vinfo) { + file << *(i.tx); + file << (int64_t)i.nTime; + file << (int64_t)i.nFeeDelta; + mapDeltas.erase(i.tx->GetHash()); + } + + file << mapDeltas; + if (!FileCommit(file.Get())) + throw std::runtime_error("FileCommit failed"); + file.fclose(); + RenameOver(GetDataDir() / "mempool.dat.new", GetDataDir() / "mempool.dat"); + int64_t last = GetTimeMicros(); + LogPrintf("Dumped mempool: %gs to copy, %gs to dump\n", (mid-start)*MICRO, (last-mid)*MICRO); + } catch (const std::exception& e) { + LogPrintf("Failed to dump mempool: %s. Continuing anyway.\n", e.what()); + return false; + } + return true; +} + +//! Guess how far we are in the verification process at the given block index +//! require cs_main if pindex has not been validated yet (because nChainTx might be unset) +double GuessVerificationProgress(const ChainTxData& data, const CBlockIndex *pindex) { + if (pindex == nullptr) + return 0.0; + + int64_t nNow = time(nullptr); + + double fTxTotal; + + if (pindex->nChainTx <= data.nTxCount) { + fTxTotal = data.nTxCount + (nNow - data.nTime) * data.dTxRate; + } else { + fTxTotal = pindex->nChainTx + (nNow - pindex->GetBlockTime()) * data.dTxRate; + } + + return pindex->nChainTx / fTxTotal; +} + +class CMainCleanup +{ +public: + CMainCleanup() {} + ~CMainCleanup() { + // block headers + BlockMap::iterator it1 = mapBlockIndex.begin(); + for (; it1 != mapBlockIndex.end(); it1++) + delete (*it1).second; + mapBlockIndex.clear(); + } +} instance_of_cmaincleanup; |