1 // Copyright (c) 2009-2010 Satoshi Nakamoto
2 // Copyright (c) 2009-2014 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.
9 #if defined(HAVE_CONFIG_H)
10 #include "config/bitcoin-config.h"
15 #include "chainparams.h"
17 #include "consensus/consensus.h"
19 #include "primitives/block.h"
20 #include "primitives/transaction.h"
21 #include "script/script.h"
22 #include "script/sigcache.h"
23 #include "script/standard.h"
25 #include "tinyformat.h"
26 #include "txmempool.h"
38 #include <boost/unordered_map.hpp>
45 class CValidationInterface;
46 class CValidationState;
48 struct CNodeStateStats;
50 /** Default for -blockmaxsize and -blockminsize, which control the range of sizes the mining code will create **/
51 static const unsigned int DEFAULT_BLOCK_MAX_SIZE = MAX_BLOCK_SIZE;
52 static const unsigned int DEFAULT_BLOCK_MIN_SIZE = 0;
53 /** Default for -blockprioritysize, maximum space for zero/low-fee transactions **/
54 static const unsigned int DEFAULT_BLOCK_PRIORITY_SIZE = DEFAULT_BLOCK_MAX_SIZE / 2;
55 /** Default for accepting alerts from the P2P network. */
56 static const bool DEFAULT_ALERTS = true;
57 /** Minimum alert priority for enabling safe mode. */
58 static const int ALERT_PRIORITY_SAFE_MODE = 4000;
59 /** Maximum number of signature check operations in an IsStandard() P2SH script */
60 static const unsigned int MAX_P2SH_SIGOPS = 15;
61 /** The maximum number of sigops we're willing to relay/mine in a single tx */
62 static const unsigned int MAX_STANDARD_TX_SIGOPS = MAX_BLOCK_SIGOPS/5;
63 /** Default for -minrelaytxfee, minimum relay fee for transactions */
64 static const unsigned int DEFAULT_MIN_RELAY_TX_FEE = 1000;
65 /** Default for -maxorphantx, maximum number of orphan transactions kept in memory */
66 static const unsigned int DEFAULT_MAX_ORPHAN_TRANSACTIONS = 100;
67 /** The maximum size of a blk?????.dat file (since 0.8) */
68 static const unsigned int MAX_BLOCKFILE_SIZE = 0x8000000; // 128 MiB
69 /** The pre-allocation chunk size for blk?????.dat files (since 0.8) */
70 static const unsigned int BLOCKFILE_CHUNK_SIZE = 0x1000000; // 16 MiB
71 /** The pre-allocation chunk size for rev?????.dat files (since 0.8) */
72 static const unsigned int UNDOFILE_CHUNK_SIZE = 0x100000; // 1 MiB
73 /** Maximum number of script-checking threads allowed */
74 static const int MAX_SCRIPTCHECK_THREADS = 16;
75 /** -par default (number of script-checking threads, 0 = auto) */
76 static const int DEFAULT_SCRIPTCHECK_THREADS = 0;
77 /** Number of blocks that can be requested at any given time from a single peer. */
78 static const int MAX_BLOCKS_IN_TRANSIT_PER_PEER = 16;
79 /** Timeout in seconds during which a peer must stall block download progress before being disconnected. */
80 static const unsigned int BLOCK_STALLING_TIMEOUT = 2;
81 /** Number of headers sent in one getheaders result. We rely on the assumption that if a peer sends
82 * less than this number, we reached its tip. Changing this value is a protocol upgrade. */
83 static const unsigned int MAX_HEADERS_RESULTS = 160;
84 /** Size of the "block download window": how far ahead of our current height do we fetch?
85 * Larger windows tolerate larger download speed differences between peer, but increase the potential
86 * degree of disordering of blocks on disk (which make reindexing and in the future perhaps pruning
87 * harder). We'll probably want to make this a per-peer adaptive value at some point. */
88 static const unsigned int BLOCK_DOWNLOAD_WINDOW = 1024;
89 /** Time to wait (in seconds) between writing blocks/block index to disk. */
90 static const unsigned int DATABASE_WRITE_INTERVAL = 60 * 60;
91 /** Time to wait (in seconds) between flushing chainstate to disk. */
92 static const unsigned int DATABASE_FLUSH_INTERVAL = 24 * 60 * 60;
93 /** Maximum length of reject messages. */
94 static const unsigned int MAX_REJECT_MESSAGE_LENGTH = 111;
96 // Sanity check the magic numbers when we change them
97 BOOST_STATIC_ASSERT(DEFAULT_BLOCK_MAX_SIZE <= MAX_BLOCK_SIZE);
98 BOOST_STATIC_ASSERT(DEFAULT_BLOCK_PRIORITY_SIZE <= DEFAULT_BLOCK_MAX_SIZE);
100 #define equihash_parameters_acceptable(N, K) \
101 ((CBlockHeader::HEADER_SIZE + equihash_solution_size(N, K))*MAX_HEADERS_RESULTS < \
102 MAX_PROTOCOL_MESSAGE_LENGTH-1000)
106 size_t operator()(const uint256& hash) const { return hash.GetCheapHash(); }
109 extern CScript COINBASE_FLAGS;
110 extern CCriticalSection cs_main;
111 extern CTxMemPool mempool;
112 typedef boost::unordered_map<uint256, CBlockIndex*, BlockHasher> BlockMap;
113 extern BlockMap mapBlockIndex;
114 extern uint64_t nLastBlockTx;
115 extern uint64_t nLastBlockSize;
116 extern const std::string strMessageMagic;
117 extern CWaitableCriticalSection csBestBlock;
118 extern CConditionVariable cvBlockChange;
119 extern bool fImporting;
120 extern bool fReindex;
121 extern int nScriptCheckThreads;
122 extern bool fTxIndex;
123 extern bool fIsBareMultisigStd;
124 extern bool fCheckBlockIndex;
125 extern bool fCheckpointsEnabled;
126 // TODO: remove this flag by structuring our code such that
127 // it is unneeded for testing
128 extern bool fCoinbaseEnforcedProtectionEnabled;
129 extern size_t nCoinCacheUsage;
130 extern CFeeRate minRelayTxFee;
133 /** Best header we've seen so far (used for getheaders queries' starting points). */
134 extern CBlockIndex *pindexBestHeader;
136 /** Minimum disk space required - used in CheckDiskSpace() */
137 static const uint64_t nMinDiskSpace = 52428800;
139 /** Pruning-related variables and constants */
140 /** True if any block files have ever been pruned. */
141 extern bool fHavePruned;
142 /** True if we're running in -prune mode. */
143 extern bool fPruneMode;
144 /** Number of MiB of block files that we're trying to stay below. */
145 extern uint64_t nPruneTarget;
146 /** Block files containing a block-height within MIN_BLOCKS_TO_KEEP of chainActive.Tip() will not be pruned. */
147 static const signed int MIN_BLOCKS_TO_KEEP = 288;
149 // Require that user allocate at least 550MB for block & undo files (blk???.dat and rev???.dat)
150 // At 1MB per block, 288 blocks = 288MB.
151 // Add 15% for Undo data = 331MB
152 // Add 20% for Orphan block rate = 397MB
153 // We want the low water mark after pruning to be at least 397 MB and since we prune in
154 // full block file chunks, we need the high water mark which triggers the prune to be
155 // one 128MB block file + added 15% undo data = 147MB greater for a total of 545MB
156 // Setting the target to > than 550MB will make it likely we can respect the target.
157 static const signed int MIN_DISK_SPACE_FOR_BLOCK_FILES = 550 * 1024 * 1024;
159 /** Register with a network node to receive its signals */
160 void RegisterNodeSignals(CNodeSignals& nodeSignals);
161 /** Unregister a network node */
162 void UnregisterNodeSignals(CNodeSignals& nodeSignals);
165 * Process an incoming block. This only returns after the best known valid
166 * block is made active. Note that it does not, however, guarantee that the
167 * specific block passed to it has been checked for validity!
169 * @param[out] state This may be set to an Error state if any error occurred processing it, including during validation/connection/etc of otherwise unrelated blocks during reorganisation; or it may be set to an Invalid state if pblock is itself invalid (but this is not guaranteed even when the block is checked). If you want to *possibly* get feedback on whether pblock is valid, you must also install a CValidationInterface (see validationinterface.h) - this will have its BlockChecked method called whenever *any* block completes validation.
170 * @param[in] pfrom The node which we are receiving the block from; it is added to mapBlockSource and may be penalised if the block is invalid.
171 * @param[in] pblock The block we want to process.
172 * @param[in] fForceProcessing Process this block even if unrequested; used for non-network block sources and whitelisted peers.
173 * @param[out] dbp If pblock is stored to disk (or already there), this will be set to its location.
174 * @return True if state.IsValid()
176 bool ProcessNewBlock(CValidationState &state, CNode* pfrom, CBlock* pblock, bool fForceProcessing, CDiskBlockPos *dbp);
177 /** Check whether enough disk space is available for an incoming block */
178 bool CheckDiskSpace(uint64_t nAdditionalBytes = 0);
179 /** Open a block file (blk?????.dat) */
180 FILE* OpenBlockFile(const CDiskBlockPos &pos, bool fReadOnly = false);
181 /** Open an undo file (rev?????.dat) */
182 FILE* OpenUndoFile(const CDiskBlockPos &pos, bool fReadOnly = false);
183 /** Translation to a filesystem path */
184 boost::filesystem::path GetBlockPosFilename(const CDiskBlockPos &pos, const char *prefix);
185 /** Import blocks from an external file */
186 bool LoadExternalBlockFile(FILE* fileIn, CDiskBlockPos *dbp = NULL);
187 /** Initialize a new block tree database + block data on disk */
188 bool InitBlockIndex();
189 /** Load the block tree and coins database from disk */
190 bool LoadBlockIndex();
191 /** Unload database information */
192 void UnloadBlockIndex();
193 /** Process protocol messages received from a given node */
194 bool ProcessMessages(CNode* pfrom);
196 * Send queued protocol messages to be sent to a give node.
198 * @param[in] pto The node which we are sending messages to.
199 * @param[in] fSendTrickle When true send the trickled data, otherwise trickle the data until true.
201 bool SendMessages(CNode* pto, bool fSendTrickle);
202 /** Run an instance of the script checking thread */
203 void ThreadScriptCheck();
204 /** Try to detect Partition (network isolation) attacks against us */
205 void PartitionCheck(bool (*initialDownloadCheck)(), CCriticalSection& cs, const CBlockIndex *const &bestHeader, int64_t nPowTargetSpacing);
206 /** Check whether we are doing an initial block download (synchronizing from disk or network) */
207 bool IsInitialBlockDownload();
208 /** Format a string that describes several potential problems detected by the core */
209 std::string GetWarnings(std::string strFor);
210 /** Retrieve a transaction (from memory pool, or from disk, if possible) */
211 bool GetTransaction(const uint256 &hash, CTransaction &tx, uint256 &hashBlock, bool fAllowSlow = false);
212 /** Find the best known block, and make it the tip of the block chain */
213 bool ActivateBestChain(CValidationState &state, CBlock *pblock = NULL);
214 CAmount GetBlockSubsidy(int nHeight, const Consensus::Params& consensusParams);
217 * Prune block and undo files (blk???.dat and undo???.dat) so that the disk space used is less than a user-defined target.
218 * The user sets the target (in MB) on the command line or in config file. This will be run on startup and whenever new
219 * space is allocated in a block or undo file, staying below the target. Changing back to unpruned requires a reindex
220 * (which in this case means the blockchain must be re-downloaded.)
222 * Pruning functions are called from FlushStateToDisk when the global fCheckForPruning flag has been set.
223 * Block and undo files are deleted in lock-step (when blk00003.dat is deleted, so is rev00003.dat.)
224 * Pruning cannot take place until the longest chain is at least a certain length (100000 on mainnet, 1000 on testnet, 10 on regtest).
225 * Pruning will never delete a block within a defined distance (currently 288) from the active chain's tip.
226 * The block index is updated by unsetting HAVE_DATA and HAVE_UNDO for any blocks that were stored in the deleted files.
227 * A db flag records the fact that at least some block files have been pruned.
229 * @param[out] setFilesToPrune The set of file indices that can be unlinked will be returned
231 void FindFilesToPrune(std::set<int>& setFilesToPrune);
234 * Actually unlink the specified files
236 void UnlinkPrunedFiles(std::set<int>& setFilesToPrune);
238 /** Create a new block index entry for a given block hash */
239 CBlockIndex * InsertBlockIndex(uint256 hash);
240 /** Get statistics from node state */
241 bool GetNodeStateStats(NodeId nodeid, CNodeStateStats &stats);
242 /** Increase a node's misbehavior score. */
243 void Misbehaving(NodeId nodeid, int howmuch);
244 /** Flush all state, indexes and buffers to disk. */
245 void FlushStateToDisk();
246 /** Prune block files and flush state to disk. */
247 void PruneAndFlush();
249 /** (try to) add transaction to memory pool **/
250 bool AcceptToMemoryPool(CTxMemPool& pool, CValidationState &state, const CTransaction &tx, bool fLimitFree,
251 bool* pfMissingInputs, bool fRejectAbsurdFee=false);
254 struct CNodeStateStats {
258 std::vector<int> vHeightInFlight;
261 struct CDiskTxPos : public CDiskBlockPos
263 unsigned int nTxOffset; // after header
265 ADD_SERIALIZE_METHODS;
267 template <typename Stream, typename Operation>
268 inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
269 READWRITE(*(CDiskBlockPos*)this);
270 READWRITE(VARINT(nTxOffset));
273 CDiskTxPos(const CDiskBlockPos &blockIn, unsigned int nTxOffsetIn) : CDiskBlockPos(blockIn.nFile, blockIn.nPos), nTxOffset(nTxOffsetIn) {
281 CDiskBlockPos::SetNull();
287 CAmount GetMinRelayFee(const CTransaction& tx, unsigned int nBytes, bool fAllowFree);
290 * Check transaction inputs, and make sure any
291 * pay-to-script-hash transactions are evaluating IsStandard scripts
293 * Why bother? To avoid denial-of-service attacks; an attacker
294 * can submit a standard HASH... OP_EQUAL transaction,
295 * which will get accepted into blocks. The redemption
296 * script can be anything; an attacker could use a very
297 * expensive-to-check-upon-redemption script like:
298 * DUP CHECKSIG DROP ... repeated 100 times... OP_1
302 * Check for standard transaction types
303 * @param[in] mapInputs Map of previous transactions that have outputs we're spending
304 * @return True if all inputs (scriptSigs) use only standard transaction forms
306 bool AreInputsStandard(const CTransaction& tx, const CCoinsViewCache& mapInputs);
309 * Count ECDSA signature operations the old-fashioned (pre-0.6) way
310 * @return number of sigops this transaction's outputs will produce when spent
311 * @see CTransaction::FetchInputs
313 unsigned int GetLegacySigOpCount(const CTransaction& tx);
316 * Count ECDSA signature operations in pay-to-script-hash inputs.
318 * @param[in] mapInputs Map of previous transactions that have outputs we're spending
319 * @return maximum number of sigops required to validate this transaction's inputs
320 * @see CTransaction::FetchInputs
322 unsigned int GetP2SHSigOpCount(const CTransaction& tx, const CCoinsViewCache& mapInputs);
326 * Check whether all inputs of this transaction are valid (no double spends, scripts & sigs, amounts)
327 * This does not modify the UTXO set. If pvChecks is not NULL, script checks are pushed onto it
328 * instead of being performed inline.
330 bool ContextualCheckInputs(const CTransaction& tx, CValidationState &state, const CCoinsViewCache &view, bool fScriptChecks,
331 unsigned int flags, bool cacheStore, const Consensus::Params& consensusParams,
332 std::vector<CScriptCheck> *pvChecks = NULL);
334 bool NonContextualCheckInputs(const CTransaction& tx, CValidationState &state, const CCoinsViewCache &view, bool fScriptChecks,
335 unsigned int flags, bool cacheStore, const Consensus::Params& consensusParams,
336 std::vector<CScriptCheck> *pvChecks = NULL);
338 /** Apply the effects of this transaction on the UTXO set represented by view */
339 void UpdateCoins(const CTransaction& tx, CValidationState &state, CCoinsViewCache &inputs, int nHeight);
341 /** Context-independent validity checks */
342 bool CheckTransaction(const CTransaction& tx, CValidationState& state, libzcash::ProofVerifier& verifier);
343 bool CheckTransactionWithoutProofVerification(const CTransaction& tx, CValidationState &state);
345 /** Check for standard transaction types
346 * @return True if all outputs (scriptPubKeys) use only standard transaction forms
348 bool IsStandardTx(const CTransaction& tx, std::string& reason);
351 * Check if transaction is final and can be included in a block with the
352 * specified height and time. Consensus critical.
354 bool IsFinalTx(const CTransaction &tx, int nBlockHeight, int64_t nBlockTime);
357 * Check if transaction will be final in the next block to be created.
359 * Calls IsFinalTx() with current block height and appropriate block time.
361 * See consensus/consensus.h for flag definitions.
363 bool CheckFinalTx(const CTransaction &tx, int flags = -1);
366 * Closure representing one script verification
367 * Note that this stores references to the spending transaction
372 CScript scriptPubKey;
373 const CTransaction *ptxTo;
380 CScriptCheck(): ptxTo(0), nIn(0), nFlags(0), cacheStore(false), error(SCRIPT_ERR_UNKNOWN_ERROR) {}
381 CScriptCheck(const CCoins& txFromIn, const CTransaction& txToIn, unsigned int nInIn, unsigned int nFlagsIn, bool cacheIn) :
382 scriptPubKey(txFromIn.vout[txToIn.vin[nInIn].prevout.n].scriptPubKey),
383 ptxTo(&txToIn), nIn(nInIn), nFlags(nFlagsIn), cacheStore(cacheIn), error(SCRIPT_ERR_UNKNOWN_ERROR) { }
387 void swap(CScriptCheck &check) {
388 scriptPubKey.swap(check.scriptPubKey);
389 std::swap(ptxTo, check.ptxTo);
390 std::swap(nIn, check.nIn);
391 std::swap(nFlags, check.nFlags);
392 std::swap(cacheStore, check.cacheStore);
393 std::swap(error, check.error);
396 ScriptError GetScriptError() const { return error; }
400 /** Functions for disk access for blocks */
401 bool WriteBlockToDisk(CBlock& block, CDiskBlockPos& pos, const CMessageHeader::MessageStartChars& messageStart);
402 bool ReadBlockFromDisk(CBlock& block, const CDiskBlockPos& pos);
403 bool ReadBlockFromDisk(CBlock& block, const CBlockIndex* pindex);
406 /** Functions for validating blocks and updating the block tree */
408 /** Undo the effects of this block (with given index) on the UTXO set represented by coins.
409 * In case pfClean is provided, operation will try to be tolerant about errors, and *pfClean
410 * will be true if no problems were found. Otherwise, the return value will be false in case
411 * of problems. Note that in any case, coins may be modified. */
412 bool DisconnectBlock(CBlock& block, CValidationState& state, CBlockIndex* pindex, CCoinsViewCache& coins, bool* pfClean = NULL);
414 /** Apply the effects of this block (with given index) on the UTXO set represented by coins */
415 bool ConnectBlock(const CBlock& block, CValidationState& state, CBlockIndex* pindex, CCoinsViewCache& coins, bool fJustCheck = false);
417 /** Context-independent validity checks */
418 bool CheckBlockHeader(const CBlockHeader& block, CValidationState& state, bool fCheckPOW = true);
419 bool CheckBlock(const CBlock& block, CValidationState& state,
420 libzcash::ProofVerifier& verifier,
421 bool fCheckPOW = true, bool fCheckMerkleRoot = true);
423 /** Context-dependent validity checks */
424 bool ContextualCheckBlockHeader(const CBlockHeader& block, CValidationState& state, CBlockIndex *pindexPrev);
425 bool ContextualCheckBlock(const CBlock& block, CValidationState& state, CBlockIndex *pindexPrev);
427 /** Check a block is completely valid from start to finish (only works on top of our current best block, with cs_main held) */
428 bool TestBlockValidity(CValidationState &state, const CBlock& block, CBlockIndex *pindexPrev, bool fCheckPOW = true, bool fCheckMerkleRoot = true);
431 * Store block on disk.
432 * JoinSplit proofs are never verified, because:
433 * - AcceptBlock doesn't perform script checks either.
434 * - The only caller of AcceptBlock verifies JoinSplit proofs elsewhere.
435 * If dbp is non-NULL, the file is known to already reside on disk
437 bool AcceptBlock(CBlock& block, CValidationState& state, CBlockIndex **pindex, bool fRequested, CDiskBlockPos* dbp);
438 bool AcceptBlockHeader(const CBlockHeader& block, CValidationState& state, CBlockIndex **ppindex= NULL);
445 unsigned int nBlocks; //! number of blocks stored in file
446 unsigned int nSize; //! number of used bytes of block file
447 unsigned int nUndoSize; //! number of used bytes in the undo file
448 unsigned int nHeightFirst; //! lowest height of block in file
449 unsigned int nHeightLast; //! highest height of block in file
450 uint64_t nTimeFirst; //! earliest time of block in file
451 uint64_t nTimeLast; //! latest time of block in file
453 ADD_SERIALIZE_METHODS;
455 template <typename Stream, typename Operation>
456 inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
457 READWRITE(VARINT(nBlocks));
458 READWRITE(VARINT(nSize));
459 READWRITE(VARINT(nUndoSize));
460 READWRITE(VARINT(nHeightFirst));
461 READWRITE(VARINT(nHeightLast));
462 READWRITE(VARINT(nTimeFirst));
463 READWRITE(VARINT(nTimeLast));
480 std::string ToString() const;
482 /** update statistics (does not update nSize) */
483 void AddBlock(unsigned int nHeightIn, uint64_t nTimeIn) {
484 if (nBlocks==0 || nHeightFirst > nHeightIn)
485 nHeightFirst = nHeightIn;
486 if (nBlocks==0 || nTimeFirst > nTimeIn)
487 nTimeFirst = nTimeIn;
489 if (nHeightIn > nHeightLast)
490 nHeightLast = nHeightIn;
491 if (nTimeIn > nTimeLast)
496 /** RAII wrapper for VerifyDB: Verify consistency of the block and coin databases */
501 bool VerifyDB(CCoinsView *coinsview, int nCheckLevel, int nCheckDepth);
504 /** Find the last common block between the parameter chain and a locator. */
505 CBlockIndex* FindForkInGlobalIndex(const CChain& chain, const CBlockLocator& locator);
507 /** Mark a block as invalid. */
508 bool InvalidateBlock(CValidationState& state, CBlockIndex *pindex);
510 /** Remove invalidity status from a block and its descendants. */
511 bool ReconsiderBlock(CValidationState& state, CBlockIndex *pindex);
513 /** The currently-connected chain of blocks. */
514 extern CChain chainActive;
516 /** Global variable that points to the active CCoinsView (protected by cs_main) */
517 extern CCoinsViewCache *pcoinsTip;
519 /** Global variable that points to the active block tree (protected by cs_main) */
520 extern CBlockTreeDB *pblocktree;
522 #endif // BITCOIN_MAIN_H