// Copyright (c) 2009-2010 Satoshi Nakamoto // Copyright (c) 2009-2016 The Bitcoin Core developers // Distributed under the MIT software license, see the accompanying // file COPYING or http://www.opensource.org/licenses/mit-license.php. #ifndef BITCOIN_VALIDATION_H #define BITCOIN_VALIDATION_H #if defined(HAVE_CONFIG_H) #include "config/bitcoin-config.h" #endif #include "amount.h" #include "coins.h" #include "fs.h" #include "protocol.h" // For CMessageHeader::MessageStartChars #include "policy/feerate.h" #include "script/script_error.h" #include "sync.h" #include "versionbits.h" #include #include #include #include #include #include #include #include #include #include class CBlockIndex; class CBlockTreeDB; class CBloomFilter; class CChainParams; class CInv; class CConnman; class CScriptCheck; class CBlockPolicyEstimator; class CTxMemPool; class CValidationInterface; class CValidationState; struct ChainTxData; struct PrecomputedTransactionData; struct LockPoints; /** Default for DEFAULT_WHITELISTRELAY. */ static const bool DEFAULT_WHITELISTRELAY = true; /** Default for DEFAULT_WHITELISTFORCERELAY. */ static const bool DEFAULT_WHITELISTFORCERELAY = true; /** Default for -minrelaytxfee, minimum relay fee for transactions */ static const unsigned int DEFAULT_MIN_RELAY_TX_FEE = 1000; //! -maxtxfee default static const CAmount DEFAULT_TRANSACTION_MAXFEE = 0.1 * COIN; //! Discourage users to set fees higher than this amount (in satoshis) per kB static const CAmount HIGH_TX_FEE_PER_KB = 0.01 * COIN; //! -maxtxfee will warn if called with a higher fee than this amount (in satoshis) static const CAmount HIGH_MAX_TX_FEE = 100 * HIGH_TX_FEE_PER_KB; /** Default for -limitancestorcount, max number of in-mempool ancestors */ static const unsigned int DEFAULT_ANCESTOR_LIMIT = 25; /** Default for -limitancestorsize, maximum kilobytes of tx + all in-mempool ancestors */ static const unsigned int DEFAULT_ANCESTOR_SIZE_LIMIT = 101; /** Default for -limitdescendantcount, max number of in-mempool descendants */ static const unsigned int DEFAULT_DESCENDANT_LIMIT = 25; /** Default for -limitdescendantsize, maximum kilobytes of in-mempool descendants */ static const unsigned int DEFAULT_DESCENDANT_SIZE_LIMIT = 101; /** Default for -mempoolexpiry, expiration time for mempool transactions in hours */ static const unsigned int DEFAULT_MEMPOOL_EXPIRY = 336; /** Maximum kilobytes for transactions to store for processing during reorg */ static const unsigned int MAX_DISCONNECTED_TX_POOL_SIZE = 20000; /** The maximum size of a blk?????.dat file (since 0.8) */ static const unsigned int MAX_BLOCKFILE_SIZE = 0x8000000; // 128 MiB /** The pre-allocation chunk size for blk?????.dat files (since 0.8) */ static const unsigned int BLOCKFILE_CHUNK_SIZE = 0x1000000; // 16 MiB /** The pre-allocation chunk size for rev?????.dat files (since 0.8) */ static const unsigned int UNDOFILE_CHUNK_SIZE = 0x100000; // 1 MiB /** Maximum number of script-checking threads allowed */ static const int MAX_SCRIPTCHECK_THREADS = 16; /** -par default (number of script-checking threads, 0 = auto) */ static const int DEFAULT_SCRIPTCHECK_THREADS = 0; /** Number of blocks that can be requested at any given time from a single peer. */ static const int MAX_BLOCKS_IN_TRANSIT_PER_PEER = 16; /** Timeout in seconds during which a peer must stall block download progress before being disconnected. */ static const unsigned int BLOCK_STALLING_TIMEOUT = 2; /** Number of headers sent in one getheaders result. We rely on the assumption that if a peer sends * less than this number, we reached its tip. Changing this value is a protocol upgrade. */ static const unsigned int MAX_HEADERS_RESULTS = 2000; /** Maximum depth of blocks we're willing to serve as compact blocks to peers * when requested. For older blocks, a regular BLOCK response will be sent. */ static const int MAX_CMPCTBLOCK_DEPTH = 5; /** Maximum depth of blocks we're willing to respond to GETBLOCKTXN requests for. */ static const int MAX_BLOCKTXN_DEPTH = 10; /** Size of the "block download window": how far ahead of our current height do we fetch? * Larger windows tolerate larger download speed differences between peer, but increase the potential * degree of disordering of blocks on disk (which make reindexing and in the future perhaps pruning * harder). We'll probably want to make this a per-peer adaptive value at some point. */ static const unsigned int BLOCK_DOWNLOAD_WINDOW = 1024; /** Time to wait (in seconds) between writing blocks/block index to disk. */ static const unsigned int DATABASE_WRITE_INTERVAL = 60 * 60; /** Time to wait (in seconds) between flushing chainstate to disk. */ static const unsigned int DATABASE_FLUSH_INTERVAL = 24 * 60 * 60; /** Maximum length of reject messages. */ static const unsigned int MAX_REJECT_MESSAGE_LENGTH = 111; /** Average delay between local address broadcasts in seconds. */ static const unsigned int AVG_LOCAL_ADDRESS_BROADCAST_INTERVAL = 24 * 60 * 60; /** Average delay between peer address broadcasts in seconds. */ static const unsigned int AVG_ADDRESS_BROADCAST_INTERVAL = 30; /** Average delay between trickled inventory transmissions in seconds. * Blocks and whitelisted receivers bypass this, outbound peers get half this delay. */ static const unsigned int INVENTORY_BROADCAST_INTERVAL = 5; /** Maximum number of inventory items to send per transmission. * Limits the impact of low-fee transaction floods. */ static const unsigned int INVENTORY_BROADCAST_MAX = 7 * INVENTORY_BROADCAST_INTERVAL; /** Average delay between feefilter broadcasts in seconds. */ static const unsigned int AVG_FEEFILTER_BROADCAST_INTERVAL = 10 * 60; /** Maximum feefilter broadcast delay after significant change. */ static const unsigned int MAX_FEEFILTER_CHANGE_DELAY = 5 * 60; /** Block download timeout base, expressed in millionths of the block interval (i.e. 10 min) */ static const int64_t BLOCK_DOWNLOAD_TIMEOUT_BASE = 1000000; /** Additional block download timeout per parallel downloading peer (i.e. 5 min) */ static const int64_t BLOCK_DOWNLOAD_TIMEOUT_PER_PEER = 500000; static const int64_t DEFAULT_MAX_TIP_AGE = 24 * 60 * 60; /** Maximum age of our tip in seconds for us to be considered current for fee estimation */ static const int64_t MAX_FEE_ESTIMATION_TIP_AGE = 3 * 60 * 60; /** Default for -permitbaremultisig */ static const bool DEFAULT_PERMIT_BAREMULTISIG = true; static const bool DEFAULT_CHECKPOINTS_ENABLED = true; static const bool DEFAULT_TXINDEX = false; static const unsigned int DEFAULT_BANSCORE_THRESHOLD = 100; /** Default for -persistmempool */ static const bool DEFAULT_PERSIST_MEMPOOL = true; /** Default for -mempoolreplacement */ static const bool DEFAULT_ENABLE_REPLACEMENT = true; /** Default for using fee filter */ static const bool DEFAULT_FEEFILTER = true; /** Maximum number of headers to announce when relaying blocks with headers message.*/ static const unsigned int MAX_BLOCKS_TO_ANNOUNCE = 8; /** Maximum number of unconnecting headers announcements before DoS score */ static const int MAX_UNCONNECTING_HEADERS = 10; static const bool DEFAULT_PEERBLOOMFILTERS = true; /** Default for -stopatheight */ static const int DEFAULT_STOPATHEIGHT = 0; struct BlockHasher { size_t operator()(const uint256& hash) const { return hash.GetCheapHash(); } }; extern CScript COINBASE_FLAGS; extern CCriticalSection cs_main; extern CBlockPolicyEstimator feeEstimator; extern CTxMemPool mempool; typedef boost::unordered_map BlockMap; extern BlockMap mapBlockIndex; extern uint64_t nLastBlockTx; extern uint64_t nLastBlockSize; extern uint64_t nLastBlockWeight; extern const std::string strMessageMagic; extern CWaitableCriticalSection csBestBlock; extern CConditionVariable cvBlockChange; extern std::atomic_bool fImporting; extern bool fReindex; extern int nScriptCheckThreads; extern bool fTxIndex; extern bool fIsBareMultisigStd; extern bool fRequireStandard; extern bool fCheckBlockIndex; extern bool fCheckpointsEnabled; extern size_t nCoinCacheUsage; /** A fee rate smaller than this is considered zero fee (for relaying, mining and transaction creation) */ extern CFeeRate minRelayTxFee; /** Absolute maximum transaction fee (in satoshis) used by wallet and mempool (rejects high fee in sendrawtransaction) */ extern CAmount maxTxFee; /** If the tip is older than this (in seconds), the node is considered to be in initial block download. */ extern int64_t nMaxTipAge; extern bool fEnableReplacement; /** Block hash whose ancestors we will assume to have valid scripts without checking them. */ extern uint256 hashAssumeValid; /** Best header we've seen so far (used for getheaders queries' starting points). */ extern CBlockIndex *pindexBestHeader; /** Minimum disk space required - used in CheckDiskSpace() */ static const uint64_t nMinDiskSpace = 52428800; /** Pruning-related variables and constants */ /** True if any block files have ever been pruned. */ extern bool fHavePruned; /** True if we're running in -prune mode. */ extern bool fPruneMode; /** Number of MiB of block files that we're trying to stay below. */ extern uint64_t nPruneTarget; /** Block files containing a block-height within MIN_BLOCKS_TO_KEEP of chainActive.Tip() will not be pruned. */ static const unsigned int MIN_BLOCKS_TO_KEEP = 288; static const signed int DEFAULT_CHECKBLOCKS = 6; static const unsigned int DEFAULT_CHECKLEVEL = 3; // Require that user allocate at least 550MB for block & undo files (blk???.dat and rev???.dat) // At 1MB per block, 288 blocks = 288MB. // Add 15% for Undo data = 331MB // Add 20% for Orphan block rate = 397MB // We want the low water mark after pruning to be at least 397 MB and since we prune in // full block file chunks, we need the high water mark which triggers the prune to be // one 128MB block file + added 15% undo data = 147MB greater for a total of 545MB // Setting the target to > than 550MB will make it likely we can respect the target. static const uint64_t MIN_DISK_SPACE_FOR_BLOCK_FILES = 550 * 1024 * 1024; /** * Process an incoming block. This only returns after the best known valid * block is made active. Note that it does not, however, guarantee that the * specific block passed to it has been checked for validity! * * If you want to *possibly* get feedback on whether pblock is valid, you must * install a CValidationInterface (see validationinterface.h) - this will have * its BlockChecked method called whenever *any* block completes validation. * * Note that we guarantee that either the proof-of-work is valid on pblock, or * (and possibly also) BlockChecked will have been called. * * Call without cs_main held. * * @param[in] pblock The block we want to process. * @param[in] fForceProcessing Process this block even if unrequested; used for non-network block sources and whitelisted peers. * @param[out] fNewBlock A boolean which is set to indicate if the block was first received via this call * @return True if state.IsValid() */ bool ProcessNewBlock(const CChainParams& chainparams, const std::shared_ptr pblock, bool fForceProcessing, bool* fNewBlock); /** * Process incoming block headers. * * Call without cs_main held. * * @param[in] block The block headers themselves * @param[out] state This may be set to an Error state if any error occurred processing them * @param[in] chainparams The params for the chain we want to connect to * @param[out] ppindex If set, the pointer will be set to point to the last new block index object for the given headers */ bool ProcessNewBlockHeaders(const std::vector& block, CValidationState& state, const CChainParams& chainparams, const CBlockIndex** ppindex=NULL); /** Check whether enough disk space is available for an incoming block */ bool CheckDiskSpace(uint64_t nAdditionalBytes = 0); /** Open a block file (blk?????.dat) */ FILE* OpenBlockFile(const CDiskBlockPos &pos, bool fReadOnly = false); /** Translation to a filesystem path */ fs::path GetBlockPosFilename(const CDiskBlockPos &pos, const char *prefix); /** Import blocks from an external file */ bool LoadExternalBlockFile(const CChainParams& chainparams, FILE* fileIn, CDiskBlockPos *dbp = NULL); /** Initialize a new block tree database + block data on disk */ bool InitBlockIndex(const CChainParams& chainparams); /** Load the block tree and coins database from disk */ bool LoadBlockIndex(const CChainParams& chainparams); /** Unload database information */ void UnloadBlockIndex(); /** Run an instance of the script checking thread */ void ThreadScriptCheck(); /** Check whether we are doing an initial block download (synchronizing from disk or network) */ bool IsInitialBlockDownload(); /** Format a string that describes several potential problems detected by the core. * strFor can have three values: * - "rpc": get critical warnings, which should put the client in safe mode if non-empty * - "statusbar": get all warnings * - "gui": get all warnings, translated (where possible) for GUI * This function only returns the highest priority warning of the set selected by strFor. */ std::string GetWarnings(const std::string& strFor); /** Retrieve a transaction (from memory pool, or from disk, if possible) */ bool GetTransaction(const uint256 &hash, CTransactionRef &tx, const Consensus::Params& params, uint256 &hashBlock, bool fAllowSlow = false); /** Find the best known block, and make it the tip of the block chain */ bool ActivateBestChain(CValidationState& state, const CChainParams& chainparams, std::shared_ptr pblock = std::shared_ptr()); CAmount GetBlockSubsidy(int nHeight, const Consensus::Params& consensusParams); /** Guess verification progress (as a fraction between 0.0=genesis and 1.0=current tip). */ double GuessVerificationProgress(const ChainTxData& data, CBlockIndex* pindex); /** * Mark one block file as pruned. */ void PruneOneBlockFile(const int fileNumber); /** * Actually unlink the specified files */ void UnlinkPrunedFiles(const std::set& setFilesToPrune); /** Create a new block index entry for a given block hash */ CBlockIndex * InsertBlockIndex(uint256 hash); /** Flush all state, indexes and buffers to disk. */ void FlushStateToDisk(); /** Prune block files and flush state to disk. */ void PruneAndFlush(); /** Prune block files up to a given height */ void PruneBlockFilesManual(int nManualPruneHeight); /** (try to) add transaction to memory pool * plTxnReplaced will be appended to with all transactions replaced from mempool **/ bool AcceptToMemoryPool(CTxMemPool& pool, CValidationState &state, const CTransactionRef &tx, bool fLimitFree, bool* pfMissingInputs, std::list* plTxnReplaced = NULL, bool fOverrideMempoolLimit=false, const CAmount nAbsurdFee=0); /** Convert CValidationState to a human-readable message for logging */ std::string FormatStateMessage(const CValidationState &state); /** Get the BIP9 state for a given deployment at the current tip. */ ThresholdState VersionBitsTipState(const Consensus::Params& params, Consensus::DeploymentPos pos); /** Get the numerical statistics for the BIP9 state for a given deployment at the current tip. */ BIP9Stats VersionBitsTipStatistics(const Consensus::Params& params, Consensus::DeploymentPos pos); /** Get the block height at which the BIP9 deployment switched into the state for the block building on the current tip. */ int VersionBitsTipStateSinceHeight(const Consensus::Params& params, Consensus::DeploymentPos pos); /** Apply the effects of this transaction on the UTXO set represented by view */ void UpdateCoins(const CTransaction& tx, CCoinsViewCache& inputs, int nHeight); /** Transaction validation functions */ /** * Check if transaction will be final in the next block to be created. * * Calls IsFinalTx() with current block height and appropriate block time. * * See consensus/consensus.h for flag definitions. */ bool CheckFinalTx(const CTransaction &tx, int flags = -1); /** * Test whether the LockPoints height and time are still valid on the current chain */ bool TestLockPointValidity(const LockPoints* lp); /** * Check if transaction will be BIP 68 final in the next block to be created. * * Simulates calling SequenceLocks() with data from the tip of the current active chain. * Optionally stores in LockPoints the resulting height and time calculated and the hash * of the block needed for calculation or skips the calculation and uses the LockPoints * passed in for evaluation. * The LockPoints should not be considered valid if CheckSequenceLocks returns false. * * See consensus/consensus.h for flag definitions. */ bool CheckSequenceLocks(const CTransaction &tx, int flags, LockPoints* lp = NULL, bool useExistingLockPoints = false); /** * Closure representing one script verification * Note that this stores references to the spending transaction */ class CScriptCheck { private: CScript scriptPubKey; CAmount amount; const CTransaction *ptxTo; unsigned int nIn; unsigned int nFlags; bool cacheStore; ScriptError error; PrecomputedTransactionData *txdata; public: CScriptCheck(): amount(0), ptxTo(0), nIn(0), nFlags(0), cacheStore(false), error(SCRIPT_ERR_UNKNOWN_ERROR) {} CScriptCheck(const CScript& scriptPubKeyIn, const CAmount amountIn, const CTransaction& txToIn, unsigned int nInIn, unsigned int nFlagsIn, bool cacheIn, PrecomputedTransactionData* txdataIn) : scriptPubKey(scriptPubKeyIn), amount(amountIn), ptxTo(&txToIn), nIn(nInIn), nFlags(nFlagsIn), cacheStore(cacheIn), error(SCRIPT_ERR_UNKNOWN_ERROR), txdata(txdataIn) { } bool operator()(); void swap(CScriptCheck &check) { scriptPubKey.swap(check.scriptPubKey); std::swap(ptxTo, check.ptxTo); std::swap(amount, check.amount); std::swap(nIn, check.nIn); std::swap(nFlags, check.nFlags); std::swap(cacheStore, check.cacheStore); std::swap(error, check.error); std::swap(txdata, check.txdata); } ScriptError GetScriptError() const { return error; } }; /** Functions for disk access for blocks */ bool ReadBlockFromDisk(CBlock& block, const CDiskBlockPos& pos, const Consensus::Params& consensusParams); bool ReadBlockFromDisk(CBlock& block, const CBlockIndex* pindex, const Consensus::Params& consensusParams); /** Functions for validating blocks and updating the block tree */ /** Context-independent validity checks */ bool CheckBlock(const CBlock& block, CValidationState& state, const Consensus::Params& consensusParams, bool fCheckPOW = true, bool fCheckMerkleRoot = true); /** Check a block is completely valid from start to finish (only works on top of our current best block, with cs_main held) */ bool TestBlockValidity(CValidationState& state, const CChainParams& chainparams, const CBlock& block, CBlockIndex* pindexPrev, bool fCheckPOW = true, bool fCheckMerkleRoot = true); /** Check whether witness commitments are required for block. */ bool IsWitnessEnabled(const CBlockIndex* pindexPrev, const Consensus::Params& params); /** When there are blocks in the active chain with missing data, rewind the chainstate and remove them from the block index */ bool RewindBlockIndex(const CChainParams& params); /** Update uncommitted block structures (currently: only the witness nonce). This is safe for submitted blocks. */ void UpdateUncommittedBlockStructures(CBlock& block, const CBlockIndex* pindexPrev, const Consensus::Params& consensusParams); /** Produce the necessary coinbase commitment for a block (modifies the hash, don't call for mined blocks). */ std::vector GenerateCoinbaseCommitment(CBlock& block, const CBlockIndex* pindexPrev, const Consensus::Params& consensusParams); /** RAII wrapper for VerifyDB: Verify consistency of the block and coin databases */ class CVerifyDB { public: CVerifyDB(); ~CVerifyDB(); bool VerifyDB(const CChainParams& chainparams, CCoinsView *coinsview, int nCheckLevel, int nCheckDepth); }; /** Find the last common block between the parameter chain and a locator. */ CBlockIndex* FindForkInGlobalIndex(const CChain& chain, const CBlockLocator& locator); /** Mark a block as precious and reorganize. */ bool PreciousBlock(CValidationState& state, const CChainParams& params, CBlockIndex *pindex); /** Mark a block as invalid. */ bool InvalidateBlock(CValidationState& state, const CChainParams& chainparams, CBlockIndex *pindex); /** Remove invalidity status from a block and its descendants. */ bool ResetBlockFailureFlags(CBlockIndex *pindex); /** The currently-connected chain of blocks (protected by cs_main). */ extern CChain chainActive; /** Global variable that points to the active CCoinsView (protected by cs_main) */ extern CCoinsViewCache *pcoinsTip; /** Global variable that points to the active block tree (protected by cs_main) */ extern CBlockTreeDB *pblocktree; /** * Return the spend height, which is one more than the inputs.GetBestBlock(). * While checking, GetBestBlock() refers to the parent block. (protected by cs_main) * This is also true for mempool checks. */ int GetSpendHeight(const CCoinsViewCache& inputs); extern VersionBitsCache versionbitscache; /** * Determine what nVersion a new block should use. */ int32_t ComputeBlockVersion(const CBlockIndex* pindexPrev, const Consensus::Params& params); /** Reject codes greater or equal to this can be returned by AcceptToMemPool * for transactions, to signal internal conditions. They cannot and should not * be sent over the P2P network. */ static const unsigned int REJECT_INTERNAL = 0x100; /** Too high fee. Can not be triggered by P2P transactions */ static const unsigned int REJECT_HIGHFEE = 0x100; /** Transaction is already known (either in mempool or blockchain) */ static const unsigned int REJECT_ALREADY_KNOWN = 0x101; /** Transaction conflicts with a transaction already known */ static const unsigned int REJECT_CONFLICT = 0x102; /** Get block file info entry for one block file */ CBlockFileInfo* GetBlockFileInfo(size_t n); /** Dump the mempool to disk. */ void DumpMempool(); /** Load the mempool from disk. */ bool LoadMempool(); #endif // BITCOIN_VALIDATION_H