src/validation.h

   1 // Copyright (c) 2009-2010 Satoshi Nakamoto
   2 // Copyright (c) 2009-2016 The Bitcoin Core developers
   3 // Distributed under the MIT software license, see the accompanying
   4 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
   5
   6 #ifndef BITCOIN_VALIDATION_H
   7 #define BITCOIN_VALIDATION_H
   8
   9 #if defined(HAVE_CONFIG_H)
  10 #include "config/bitcoin-config.h"
  11 #endif
  12
  13 #include "amount.h"
  14 #include "coins.h"
  15 #include "fs.h"
  16 #include "protocol.h" // For CMessageHeader::MessageStartChars
  17 #include "policy/feerate.h"
  18 #include "script/script_error.h"
  19 #include "sync.h"
  20 #include "versionbits.h"
  21
  22 #include <algorithm>
  23 #include <exception>
  24 #include <map>
  25 #include <set>
  26 #include <stdint.h>
  27 #include <string>
  28 #include <utility>
  29 #include <vector>
  30
  31 #include <atomic>
  32
  33 #include <boost/unordered_map.hpp>
  34
  35 class CBlockIndex;
  36 class CBlockTreeDB;
  37 class CBloomFilter;
  38 class CChainParams;
  39 class CInv;
  40 class CConnman;
  41 class CScriptCheck;
  42 class CBlockPolicyEstimator;
  43 class CTxMemPool;
  44 class CValidationInterface;
  45 class CValidationState;
  46 struct ChainTxData;
  47
  48 struct PrecomputedTransactionData;
  49 struct LockPoints;
  50
  51 /** Default for DEFAULT_WHITELISTRELAY. */
  52 static const bool DEFAULT_WHITELISTRELAY = true;
  53 /** Default for DEFAULT_WHITELISTFORCERELAY. */
  54 static const bool DEFAULT_WHITELISTFORCERELAY = true;
  55 /** Default for -minrelaytxfee, minimum relay fee for transactions */
  56 static const unsigned int DEFAULT_MIN_RELAY_TX_FEE = 1000;
  57 //! -maxtxfee default
  58 static const CAmount DEFAULT_TRANSACTION_MAXFEE = 0.1 * COIN;
  59 //! Discourage users to set fees higher than this amount (in satoshis) per kB
  60 static const CAmount HIGH_TX_FEE_PER_KB = 0.01 * COIN;
  61 //! -maxtxfee will warn if called with a higher fee than this amount (in satoshis)
  62 static const CAmount HIGH_MAX_TX_FEE = 100 * HIGH_TX_FEE_PER_KB;
  63 /** Default for -limitancestorcount, max number of in-mempool ancestors */
  64 static const unsigned int DEFAULT_ANCESTOR_LIMIT = 25;
  65 /** Default for -limitancestorsize, maximum kilobytes of tx + all in-mempool ancestors */
  66 static const unsigned int DEFAULT_ANCESTOR_SIZE_LIMIT = 101;
  67 /** Default for -limitdescendantcount, max number of in-mempool descendants */
  68 static const unsigned int DEFAULT_DESCENDANT_LIMIT = 25;
  69 /** Default for -limitdescendantsize, maximum kilobytes of in-mempool descendants */
  70 static const unsigned int DEFAULT_DESCENDANT_SIZE_LIMIT = 101;
  71 /** Default for -mempoolexpiry, expiration time for mempool transactions in hours */
  72 static const unsigned int DEFAULT_MEMPOOL_EXPIRY = 336;
  73 /** The maximum size of a blk?????.dat file (since 0.8) */
  74 static const unsigned int MAX_BLOCKFILE_SIZE = 0x8000000; // 128 MiB
  75 /** The pre-allocation chunk size for blk?????.dat files (since 0.8) */
  76 static const unsigned int BLOCKFILE_CHUNK_SIZE = 0x1000000; // 16 MiB
  77 /** The pre-allocation chunk size for rev?????.dat files (since 0.8) */
  78 static const unsigned int UNDOFILE_CHUNK_SIZE = 0x100000; // 1 MiB
  79
  80 /** Maximum number of script-checking threads allowed */
  81 static const int MAX_SCRIPTCHECK_THREADS = 16;
  82 /** -par default (number of script-checking threads, 0 = auto) */
  83 static const int DEFAULT_SCRIPTCHECK_THREADS = 0;
  84 /** Number of blocks that can be requested at any given time from a single peer. */
  85 static const int MAX_BLOCKS_IN_TRANSIT_PER_PEER = 16;
  86 /** Timeout in seconds during which a peer must stall block download progress before being disconnected. */
  87 static const unsigned int BLOCK_STALLING_TIMEOUT = 2;
  88 /** Number of headers sent in one getheaders result. We rely on the assumption that if a peer sends
  89  *  less than this number, we reached its tip. Changing this value is a protocol upgrade. */
  90 static const unsigned int MAX_HEADERS_RESULTS = 2000;
  91 /** Maximum depth of blocks we're willing to serve as compact blocks to peers
  92  *  when requested. For older blocks, a regular BLOCK response will be sent. */
  93 static const int MAX_CMPCTBLOCK_DEPTH = 5;
  94 /** Maximum depth of blocks we're willing to respond to GETBLOCKTXN requests for. */
  95 static const int MAX_BLOCKTXN_DEPTH = 10;
  96 /** Size of the "block download window": how far ahead of our current height do we fetch?
  97  *  Larger windows tolerate larger download speed differences between peer, but increase the potential
  98  *  degree of disordering of blocks on disk (which make reindexing and in the future perhaps pruning
  99  *  harder). We'll probably want to make this a per-peer adaptive value at some point. */
 100 static const unsigned int BLOCK_DOWNLOAD_WINDOW = 1024;
 101 /** Time to wait (in seconds) between writing blocks/block index to disk. */
 102 static const unsigned int DATABASE_WRITE_INTERVAL = 60 * 60;
 103 /** Time to wait (in seconds) between flushing chainstate to disk. */
 104 static const unsigned int DATABASE_FLUSH_INTERVAL = 24 * 60 * 60;
 105 /** Maximum length of reject messages. */
 106 static const unsigned int MAX_REJECT_MESSAGE_LENGTH = 111;
 107 /** Average delay between local address broadcasts in seconds. */
 108 static const unsigned int AVG_LOCAL_ADDRESS_BROADCAST_INTERVAL = 24 * 24 * 60;
 109 /** Average delay between peer address broadcasts in seconds. */
 110 static const unsigned int AVG_ADDRESS_BROADCAST_INTERVAL = 30;
 111 /** Average delay between trickled inventory transmissions in seconds.
 112  *  Blocks and whitelisted receivers bypass this, outbound peers get half this delay. */
 113 static const unsigned int INVENTORY_BROADCAST_INTERVAL = 5;
 114 /** Maximum number of inventory items to send per transmission.
 115  *  Limits the impact of low-fee transaction floods. */
 116 static const unsigned int INVENTORY_BROADCAST_MAX = 7 * INVENTORY_BROADCAST_INTERVAL;
 117 /** Average delay between feefilter broadcasts in seconds. */
 118 static const unsigned int AVG_FEEFILTER_BROADCAST_INTERVAL = 10 * 60;
 119 /** Maximum feefilter broadcast delay after significant change. */
 120 static const unsigned int MAX_FEEFILTER_CHANGE_DELAY = 5 * 60;
 121 /** Block download timeout base, expressed in millionths of the block interval (i.e. 10 min) */
 122 static const int64_t BLOCK_DOWNLOAD_TIMEOUT_BASE = 1000000;
 123 /** Additional block download timeout per parallel downloading peer (i.e. 5 min) */
 124 static const int64_t BLOCK_DOWNLOAD_TIMEOUT_PER_PEER = 500000;
 125
 126 static const int64_t DEFAULT_MAX_TIP_AGE = 24 * 60 * 60;
 127 /** Maximum age of our tip in seconds for us to be considered current for fee estimation */
 128 static const int64_t MAX_FEE_ESTIMATION_TIP_AGE = 3 * 60 * 60;
 129
 130 /** Default for -permitbaremultisig */
 131 static const bool DEFAULT_PERMIT_BAREMULTISIG = true;
 132 static const bool DEFAULT_CHECKPOINTS_ENABLED = true;
 133 static const bool DEFAULT_TXINDEX = false;
 134 static const unsigned int DEFAULT_BANSCORE_THRESHOLD = 100;
 135 /** Default for -persistmempool */
 136 static const bool DEFAULT_PERSIST_MEMPOOL = true;
 137 /** Default for -mempoolreplacement */
 138 static const bool DEFAULT_ENABLE_REPLACEMENT = true;
 139 /** Default for using fee filter */
 140 static const bool DEFAULT_FEEFILTER = true;
 141
 142 /** Maximum number of headers to announce when relaying blocks with headers message.*/
 143 static const unsigned int MAX_BLOCKS_TO_ANNOUNCE = 8;
 144
 145 /** Maximum number of unconnecting headers announcements before DoS score */
 146 static const int MAX_UNCONNECTING_HEADERS = 10;
 147
 148 static const bool DEFAULT_PEERBLOOMFILTERS = true;
 149
 150 /** Default for -stopatheight */
 151 static const int DEFAULT_STOPATHEIGHT = 0;
 152
 153 struct BlockHasher
 154 {
 155     size_t operator()(const uint256& hash) const { return hash.GetCheapHash(); }
 156 };
 157
 158 extern CScript COINBASE_FLAGS;
 159 extern CCriticalSection cs_main;
 160 extern CBlockPolicyEstimator feeEstimator;
 161 extern CTxMemPool mempool;
 162 typedef boost::unordered_map<uint256, CBlockIndex*, BlockHasher> BlockMap;
 163 extern BlockMap mapBlockIndex;
 164 extern uint64_t nLastBlockTx;
 165 extern uint64_t nLastBlockSize;
 166 extern uint64_t nLastBlockWeight;
 167 extern const std::string strMessageMagic;
 168 extern CWaitableCriticalSection csBestBlock;
 169 extern CConditionVariable cvBlockChange;
 170 extern std::atomic_bool fImporting;
 171 extern bool fReindex;
 172 extern int nScriptCheckThreads;
 173 extern bool fTxIndex;
 174 extern bool fIsBareMultisigStd;
 175 extern bool fRequireStandard;
 176 extern bool fCheckBlockIndex;
 177 extern bool fCheckpointsEnabled;
 178 extern size_t nCoinCacheUsage;
 179 /** A fee rate smaller than this is considered zero fee (for relaying, mining and transaction creation) */
 180 extern CFeeRate minRelayTxFee;
 181 /** Absolute maximum transaction fee (in satoshis) used by wallet and mempool (rejects high fee in sendrawtransaction) */
 182 extern CAmount maxTxFee;
 183 /** If the tip is older than this (in seconds), the node is considered to be in initial block download. */
 184 extern int64_t nMaxTipAge;
 185 extern bool fEnableReplacement;
 186
 187 /** Block hash whose ancestors we will assume to have valid scripts without checking them. */
 188 extern uint256 hashAssumeValid;
 189
 190 /** Best header we've seen so far (used for getheaders queries' starting points). */
 191 extern CBlockIndex *pindexBestHeader;
 192
 193 /** Minimum disk space required - used in CheckDiskSpace() */
 194 static const uint64_t nMinDiskSpace = 52428800;
 195
 196 /** Pruning-related variables and constants */
 197 /** True if any block files have ever been pruned. */
 198 extern bool fHavePruned;
 199 /** True if we're running in -prune mode. */
 200 extern bool fPruneMode;
 201 /** Number of MiB of block files that we're trying to stay below. */
 202 extern uint64_t nPruneTarget;
 203 /** Block files containing a block-height within MIN_BLOCKS_TO_KEEP of chainActive.Tip() will not be pruned. */
 204 static const unsigned int MIN_BLOCKS_TO_KEEP = 288;
 205
 206 static const signed int DEFAULT_CHECKBLOCKS = 6;
 207 static const unsigned int DEFAULT_CHECKLEVEL = 3;
 208
 209 // Require that user allocate at least 550MB for block & undo files (blk???.dat and rev???.dat)
 210 // At 1MB per block, 288 blocks = 288MB.
 211 // Add 15% for Undo data = 331MB
 212 // Add 20% for Orphan block rate = 397MB
 213 // We want the low water mark after pruning to be at least 397 MB and since we prune in
 214 // full block file chunks, we need the high water mark which triggers the prune to be
 215 // one 128MB block file + added 15% undo data = 147MB greater for a total of 545MB
 216 // Setting the target to > than 550MB will make it likely we can respect the target.
 217 static const uint64_t MIN_DISK_SPACE_FOR_BLOCK_FILES = 550 * 1024 * 1024;
 218
 219 /**
 220  * Process an incoming block. This only returns after the best known valid
 221  * block is made active. Note that it does not, however, guarantee that the
 222  * specific block passed to it has been checked for validity!
 223  *
 224  * If you want to *possibly* get feedback on whether pblock is valid, you must
 225  * install a CValidationInterface (see validationinterface.h) - this will have
 226  * its BlockChecked method called whenever *any* block completes validation.
 227  *
 228  * Note that we guarantee that either the proof-of-work is valid on pblock, or
 229  * (and possibly also) BlockChecked will have been called.
 230  *
 231  * Call without cs_main held.
 232  *
 233  * @param[in]   pblock  The block we want to process.
 234  * @param[in]   fForceProcessing Process this block even if unrequested; used for non-network block sources and whitelisted peers.
 235  * @param[out]  fNewBlock A boolean which is set to indicate if the block was first received via this call
 236  * @return True if state.IsValid()
 237  */
 238 bool ProcessNewBlock(const CChainParams& chainparams, const std::shared_ptr<const CBlock> pblock, bool fForceProcessing, bool* fNewBlock);
 239
 240 /**
 241  * Process incoming block headers.
 242  *
 243  * Call without cs_main held.
 244  *
 245  * @param[in]  block The block headers themselves
 246  * @param[out] state This may be set to an Error state if any error occurred processing them
 247  * @param[in]  chainparams The params for the chain we want to connect to
 248  * @param[out] ppindex If set, the pointer will be set to point to the last new block index object for the given headers
 249  */
 250 bool ProcessNewBlockHeaders(const std::vector<CBlockHeader>& block, CValidationState& state, const CChainParams& chainparams, const CBlockIndex** ppindex=NULL);
 251
 252 /** Check whether enough disk space is available for an incoming block */
 253 bool CheckDiskSpace(uint64_t nAdditionalBytes = 0);
 254 /** Open a block file (blk?????.dat) */
 255 FILE* OpenBlockFile(const CDiskBlockPos &pos, bool fReadOnly = false);
 256 /** Open an undo file (rev?????.dat) */
 257 FILE* OpenUndoFile(const CDiskBlockPos &pos, bool fReadOnly = false);
 258 /** Translation to a filesystem path */
 259 fs::path GetBlockPosFilename(const CDiskBlockPos &pos, const char *prefix);
 260 /** Import blocks from an external file */
 261 bool LoadExternalBlockFile(const CChainParams& chainparams, FILE* fileIn, CDiskBlockPos *dbp = NULL);
 262 /** Initialize a new block tree database + block data on disk */
 263 bool InitBlockIndex(const CChainParams& chainparams);
 264 /** Load the block tree and coins database from disk */
 265 bool LoadBlockIndex(const CChainParams& chainparams);
 266 /** Unload database information */
 267 void UnloadBlockIndex();
 268 /** Run an instance of the script checking thread */
 269 void ThreadScriptCheck();
 270 /** Check whether we are doing an initial block download (synchronizing from disk or network) */
 271 bool IsInitialBlockDownload();
 272 /** Format a string that describes several potential problems detected by the core.
 273  * strFor can have three values:
 274  * - "rpc": get critical warnings, which should put the client in safe mode if non-empty
 275  * - "statusbar": get all warnings
 276  * - "gui": get all warnings, translated (where possible) for GUI
 277  * This function only returns the highest priority warning of the set selected by strFor.
 278  */
 279 std::string GetWarnings(const std::string& strFor);
 280 /** Retrieve a transaction (from memory pool, or from disk, if possible) */
 281 bool GetTransaction(const uint256 &hash, CTransactionRef &tx, const Consensus::Params& params, uint256 &hashBlock, bool fAllowSlow = false);
 282 /** Find the best known block, and make it the tip of the block chain */
 283 bool ActivateBestChain(CValidationState& state, const CChainParams& chainparams, std::shared_ptr<const CBlock> pblock = std::shared_ptr<const CBlock>());
 284 CAmount GetBlockSubsidy(int nHeight, const Consensus::Params& consensusParams);
 285
 286 /** Guess verification progress (as a fraction between 0.0=genesis and 1.0=current tip). */
 287 double GuessVerificationProgress(const ChainTxData& data, CBlockIndex* pindex);
 288
 289 /**
 290  * Prune block and undo files (blk???.dat and undo???.dat) so that the disk space used is less than a user-defined target.
 291  * The user sets the target (in MB) on the command line or in config file.  This will be run on startup and whenever new
 292  * space is allocated in a block or undo file, staying below the target. Changing back to unpruned requires a reindex
 293  * (which in this case means the blockchain must be re-downloaded.)
 294  *
 295  * Pruning functions are called from FlushStateToDisk when the global fCheckForPruning flag has been set.
 296  * Block and undo files are deleted in lock-step (when blk00003.dat is deleted, so is rev00003.dat.)
 297  * Pruning cannot take place until the longest chain is at least a certain length (100000 on mainnet, 1000 on testnet, 1000 on regtest).
 298  * Pruning will never delete a block within a defined distance (currently 288) from the active chain's tip.
 299  * The block index is updated by unsetting HAVE_DATA and HAVE_UNDO for any blocks that were stored in the deleted files.
 300  * A db flag records the fact that at least some block files have been pruned.
 301  *
 302  * @param[out]   setFilesToPrune   The set of file indices that can be unlinked will be returned
 303  */
 304 void FindFilesToPrune(std::set<int>& setFilesToPrune, uint64_t nPruneAfterHeight);
 305
 306 /**
 307  *  Mark one block file as pruned.
 308  */
 309 void PruneOneBlockFile(const int fileNumber);
 310
 311 /**
 312  *  Actually unlink the specified files
 313  */
 314 void UnlinkPrunedFiles(const std::set<int>& setFilesToPrune);
 315
 316 /** Create a new block index entry for a given block hash */
 317 CBlockIndex * InsertBlockIndex(uint256 hash);
 318 /** Flush all state, indexes and buffers to disk. */
 319 void FlushStateToDisk();
 320 /** Prune block files and flush state to disk. */
 321 void PruneAndFlush();
 322 /** Prune block files up to a given height */
 323 void PruneBlockFilesManual(int nManualPruneHeight);
 324
 325 /** (try to) add transaction to memory pool
 326  * plTxnReplaced will be appended to with all transactions replaced from mempool **/
 327 bool AcceptToMemoryPool(CTxMemPool& pool, CValidationState &state, const CTransactionRef &tx, bool fLimitFree,
 328                         bool* pfMissingInputs, std::list<CTransactionRef>* plTxnReplaced = NULL,
 329                         bool fOverrideMempoolLimit=false, const CAmount nAbsurdFee=0);
 330
 331 /** (try to) add transaction to memory pool with a specified acceptance time **/
 332 bool AcceptToMemoryPoolWithTime(CTxMemPool& pool, CValidationState &state, const CTransactionRef &tx, bool fLimitFree,
 333                         bool* pfMissingInputs, int64_t nAcceptTime, std::list<CTransactionRef>* plTxnReplaced = NULL,
 334                         bool fOverrideMempoolLimit=false, const CAmount nAbsurdFee=0);
 335
 336 /** Convert CValidationState to a human-readable message for logging */
 337 std::string FormatStateMessage(const CValidationState &state);
 338
 339 /** Get the BIP9 state for a given deployment at the current tip. */
 340 ThresholdState VersionBitsTipState(const Consensus::Params& params, Consensus::DeploymentPos pos);
 341
 342 /** Get the numerical statistics for the BIP9 state for a given deployment at the current tip. */
 343 BIP9Stats VersionBitsTipStatistics(const Consensus::Params& params, Consensus::DeploymentPos pos);
 344
 345 /** Get the block height at which the BIP9 deployment switched into the state for the block building on the current tip. */
 346 int VersionBitsTipStateSinceHeight(const Consensus::Params& params, Consensus::DeploymentPos pos);
 347
 348
 349 /**
 350  * Check whether all inputs of this transaction are valid (no double spends, scripts & sigs, amounts)
 351  * This does not modify the UTXO set. If pvChecks is not NULL, script checks are pushed onto it
 352  * instead of being performed inline.
 353  */
 354 bool CheckInputs(const CTransaction& tx, CValidationState &state, const CCoinsViewCache &view, bool fScriptChecks,
 355                  unsigned int flags, bool cacheStore, PrecomputedTransactionData& txdata, std::vector<CScriptCheck> *pvChecks = NULL);
 356
 357 /** Apply the effects of this transaction on the UTXO set represented by view */
 358 void UpdateCoins(const CTransaction& tx, CCoinsViewCache& inputs, int nHeight);
 359
 360 /** Transaction validation functions */
 361
 362 /**
 363  * Check if transaction will be final in the next block to be created.
 364  *
 365  * Calls IsFinalTx() with current block height and appropriate block time.
 366  *
 367  * See consensus/consensus.h for flag definitions.
 368  */
 369 bool CheckFinalTx(const CTransaction &tx, int flags = -1);
 370
 371 /**
 372  * Test whether the LockPoints height and time are still valid on the current chain
 373  */
 374 bool TestLockPointValidity(const LockPoints* lp);
 375
 376 /**
 377  * Check if transaction will be BIP 68 final in the next block to be created.
 378  *
 379  * Simulates calling SequenceLocks() with data from the tip of the current active chain.
 380  * Optionally stores in LockPoints the resulting height and time calculated and the hash
 381  * of the block needed for calculation or skips the calculation and uses the LockPoints
 382  * passed in for evaluation.
 383  * The LockPoints should not be considered valid if CheckSequenceLocks returns false.
 384  *
 385  * See consensus/consensus.h for flag definitions.
 386  */
 387 bool CheckSequenceLocks(const CTransaction &tx, int flags, LockPoints* lp = NULL, bool useExistingLockPoints = false);
 388
 389 /**
 390  * Closure representing one script verification
 391  * Note that this stores references to the spending transaction
 392  */
 393 class CScriptCheck
 394 {
 395 private:
 396     CScript scriptPubKey;
 397     CAmount amount;
 398     const CTransaction *ptxTo;
 399     unsigned int nIn;
 400     unsigned int nFlags;
 401     bool cacheStore;
 402     ScriptError error;
 403     PrecomputedTransactionData *txdata;
 404
 405 public:
 406     CScriptCheck(): amount(0), ptxTo(0), nIn(0), nFlags(0), cacheStore(false), error(SCRIPT_ERR_UNKNOWN_ERROR) {}
 407     CScriptCheck(const CScript& scriptPubKeyIn, const CAmount amountIn, const CTransaction& txToIn, unsigned int nInIn, unsigned int nFlagsIn, bool cacheIn, PrecomputedTransactionData* txdataIn) :
 408         scriptPubKey(scriptPubKeyIn), amount(amountIn),
 409         ptxTo(&txToIn), nIn(nInIn), nFlags(nFlagsIn), cacheStore(cacheIn), error(SCRIPT_ERR_UNKNOWN_ERROR), txdata(txdataIn) { }
 410
 411     bool operator()();
 412
 413     void swap(CScriptCheck &check) {
 414         scriptPubKey.swap(check.scriptPubKey);
 415         std::swap(ptxTo, check.ptxTo);
 416         std::swap(amount, check.amount);
 417         std::swap(nIn, check.nIn);
 418         std::swap(nFlags, check.nFlags);
 419         std::swap(cacheStore, check.cacheStore);
 420         std::swap(error, check.error);
 421         std::swap(txdata, check.txdata);
 422     }
 423
 424     ScriptError GetScriptError() const { return error; }
 425 };
 426
 427
 428 /** Functions for disk access for blocks */
 429 bool WriteBlockToDisk(const CBlock& block, CDiskBlockPos& pos, const CMessageHeader::MessageStartChars& messageStart);
 430 bool ReadBlockFromDisk(CBlock& block, const CDiskBlockPos& pos, const Consensus::Params& consensusParams);
 431 bool ReadBlockFromDisk(CBlock& block, const CBlockIndex* pindex, const Consensus::Params& consensusParams);
 432
 433 /** Functions for validating blocks and updating the block tree */
 434
 435 /** Context-independent validity checks */
 436 bool CheckBlockHeader(const CBlockHeader& block, CValidationState& state, const Consensus::Params& consensusParams, bool fCheckPOW = true);
 437 bool CheckBlock(const CBlock& block, CValidationState& state, const Consensus::Params& consensusParams, bool fCheckPOW = true, bool fCheckMerkleRoot = true);
 438
 439 /** Context-dependent validity checks.
 440  *  By "context", we mean only the previous block headers, but not the UTXO
 441  *  set; UTXO-related validity checks are done in ConnectBlock(). */
 442 bool ContextualCheckBlockHeader(const CBlockHeader& block, CValidationState& state, const Consensus::Params& consensusParams, const CBlockIndex* pindexPrev, int64_t nAdjustedTime);
 443 bool ContextualCheckBlock(const CBlock& block, CValidationState& state, const Consensus::Params& consensusParams, const CBlockIndex* pindexPrev);
 444
 445 /** Check a block is completely valid from start to finish (only works on top of our current best block, with cs_main held) */
 446 bool TestBlockValidity(CValidationState& state, const CChainParams& chainparams, const CBlock& block, CBlockIndex* pindexPrev, bool fCheckPOW = true, bool fCheckMerkleRoot = true);
 447
 448 /** Check whether witness commitments are required for block. */
 449 bool IsWitnessEnabled(const CBlockIndex* pindexPrev, const Consensus::Params& params);
 450
 451 /** When there are blocks in the active chain with missing data, rewind the chainstate and remove them from the block index */
 452 bool RewindBlockIndex(const CChainParams& params);
 453
 454 /** Update uncommitted block structures (currently: only the witness nonce). This is safe for submitted blocks. */
 455 void UpdateUncommittedBlockStructures(CBlock& block, const CBlockIndex* pindexPrev, const Consensus::Params& consensusParams);
 456
 457 /** Produce the necessary coinbase commitment for a block (modifies the hash, don't call for mined blocks). */
 458 std::vector<unsigned char> GenerateCoinbaseCommitment(CBlock& block, const CBlockIndex* pindexPrev, const Consensus::Params& consensusParams);
 459
 460 /** RAII wrapper for VerifyDB: Verify consistency of the block and coin databases */
 461 class CVerifyDB {
 462 public:
 463     CVerifyDB();
 464     ~CVerifyDB();
 465     bool VerifyDB(const CChainParams& chainparams, CCoinsView *coinsview, int nCheckLevel, int nCheckDepth);
 466 };
 467
 468 /** Find the last common block between the parameter chain and a locator. */
 469 CBlockIndex* FindForkInGlobalIndex(const CChain& chain, const CBlockLocator& locator);
 470
 471 /** Mark a block as precious and reorganize. */
 472 bool PreciousBlock(CValidationState& state, const CChainParams& params, CBlockIndex *pindex);
 473
 474 /** Mark a block as invalid. */
 475 bool InvalidateBlock(CValidationState& state, const CChainParams& chainparams, CBlockIndex *pindex);
 476
 477 /** Remove invalidity status from a block and its descendants. */
 478 bool ResetBlockFailureFlags(CBlockIndex *pindex);
 479
 480 /** The currently-connected chain of blocks (protected by cs_main). */
 481 extern CChain chainActive;
 482
 483 /** Global variable that points to the active CCoinsView (protected by cs_main) */
 484 extern CCoinsViewCache *pcoinsTip;
 485
 486 /** Global variable that points to the active block tree (protected by cs_main) */
 487 extern CBlockTreeDB *pblocktree;
 488
 489 /**
 490  * Return the spend height, which is one more than the inputs.GetBestBlock().
 491  * While checking, GetBestBlock() refers to the parent block. (protected by cs_main)
 492  * This is also true for mempool checks.
 493  */
 494 int GetSpendHeight(const CCoinsViewCache& inputs);
 495
 496 extern VersionBitsCache versionbitscache;
 497
 498 /**
 499  * Determine what nVersion a new block should use.
 500  */
 501 int32_t ComputeBlockVersion(const CBlockIndex* pindexPrev, const Consensus::Params& params);
 502
 503 /** Reject codes greater or equal to this can be returned by AcceptToMemPool
 504  * for transactions, to signal internal conditions. They cannot and should not
 505  * be sent over the P2P network.
 506  */
 507 static const unsigned int REJECT_INTERNAL = 0x100;
 508 /** Too high fee. Can not be triggered by P2P transactions */
 509 static const unsigned int REJECT_HIGHFEE = 0x100;
 510 /** Transaction is already known (either in mempool or blockchain) */
 511 static const unsigned int REJECT_ALREADY_KNOWN = 0x101;
 512 /** Transaction conflicts with a transaction already known */
 513 static const unsigned int REJECT_CONFLICT = 0x102;
 514
 515 /** Get block file info entry for one block file */
 516 CBlockFileInfo* GetBlockFileInfo(size_t n);
 517
 518 /** Dump the mempool to disk. */
 519 void DumpMempool();
 520
 521 /** Load the mempool from disk. */
 522 bool LoadMempool();
 523
 524 #endif // BITCOIN_VALIDATION_H