Line data    Source code

       1             : // Copyright (c) 2009-2010 Satoshi Nakamoto
       2             : // Copyright (c) 2009-2019 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_POLICY_POLICY_H
       7             : #define BITCOIN_POLICY_POLICY_H
       8             : 
       9             : #include <consensus/consensus.h>
      10             : #include <policy/feerate.h>
      11             : #include <script/interpreter.h>
      12             : #include <script/standard.h>
      13             : 
      14             : #include <string>
      15             : 
      16             : class CCoinsViewCache;
      17             : class CTxOut;
      18             : 
      19             : /** Default for -blockmaxweight, which controls the range of block weights the mining code will create **/
      20             : static const unsigned int DEFAULT_BLOCK_MAX_WEIGHT = MAX_BLOCK_WEIGHT - 4000;
      21             : /** Default for -blockmintxfee, which sets the minimum feerate for a transaction in blocks created by mining code **/
      22             : static const unsigned int DEFAULT_BLOCK_MIN_TX_FEE = 1000;
      23             : /** The maximum weight for transactions we're willing to relay/mine */
      24             : static const unsigned int MAX_STANDARD_TX_WEIGHT = 400000;
      25             : /** The minimum non-witness size for transactions we're willing to relay/mine (1 segwit input + 1 P2WPKH output = 82 bytes) */
      26             : static const unsigned int MIN_STANDARD_TX_NONWITNESS_SIZE = 82;
      27             : /** Maximum number of signature check operations in an IsStandard() P2SH script */
      28             : static const unsigned int MAX_P2SH_SIGOPS = 15;
      29             : /** The maximum number of sigops we're willing to relay/mine in a single tx */
      30             : static const unsigned int MAX_STANDARD_TX_SIGOPS_COST = MAX_BLOCK_SIGOPS_COST/5;
      31             : /** Default for -maxmempool, maximum megabytes of mempool memory usage */
      32             : static const unsigned int DEFAULT_MAX_MEMPOOL_SIZE = 300;
      33             : /** Default for -incrementalrelayfee, which sets the minimum feerate increase for mempool limiting or BIP 125 replacement **/
      34             : static const unsigned int DEFAULT_INCREMENTAL_RELAY_FEE = 1000;
      35             : /** Default for -bytespersigop */
      36             : static const unsigned int DEFAULT_BYTES_PER_SIGOP = 20;
      37             : /** Default for -permitbaremultisig */
      38             : static const bool DEFAULT_PERMIT_BAREMULTISIG = true;
      39             : /** The maximum number of witness stack items in a standard P2WSH script */
      40             : static const unsigned int MAX_STANDARD_P2WSH_STACK_ITEMS = 100;
      41             : /** The maximum size of each witness stack item in a standard P2WSH script */
      42             : static const unsigned int MAX_STANDARD_P2WSH_STACK_ITEM_SIZE = 80;
      43             : /** The maximum size of a standard witnessScript */
      44             : static const unsigned int MAX_STANDARD_P2WSH_SCRIPT_SIZE = 3600;
      45             : /** Min feerate for defining dust. Historically this has been based on the
      46             :  * minRelayTxFee, however changing the dust limit changes which transactions are
      47             :  * standard and should be done with care and ideally rarely. It makes sense to
      48             :  * only increase the dust limit after prior releases were already not creating
      49             :  * outputs below the new threshold */
      50             : static const unsigned int DUST_RELAY_TX_FEE = 3000;
      51             : /**
      52             :  * Standard script verification flags that standard transactions will comply
      53             :  * with. However scripts violating these flags may still be present in valid
      54             :  * blocks and we must accept those blocks.
      55             :  */
      56             : static constexpr unsigned int STANDARD_SCRIPT_VERIFY_FLAGS = MANDATORY_SCRIPT_VERIFY_FLAGS |
      57             :                                                              SCRIPT_VERIFY_DERSIG |
      58             :                                                              SCRIPT_VERIFY_STRICTENC |
      59             :                                                              SCRIPT_VERIFY_MINIMALDATA |
      60             :                                                              SCRIPT_VERIFY_NULLDUMMY |
      61             :                                                              SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_NOPS |
      62             :                                                              SCRIPT_VERIFY_CLEANSTACK |
      63             :                                                              SCRIPT_VERIFY_MINIMALIF |
      64             :                                                              SCRIPT_VERIFY_NULLFAIL |
      65             :                                                              SCRIPT_VERIFY_CHECKLOCKTIMEVERIFY |
      66             :                                                              SCRIPT_VERIFY_CHECKSEQUENCEVERIFY |
      67             :                                                              SCRIPT_VERIFY_LOW_S |
      68             :                                                              SCRIPT_VERIFY_WITNESS |
      69             :                                                              SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_WITNESS_PROGRAM |
      70             :                                                              SCRIPT_VERIFY_WITNESS_PUBKEYTYPE |
      71             :                                                              SCRIPT_VERIFY_CONST_SCRIPTCODE;
      72             : 
      73             : /** For convenience, standard but not mandatory verify flags. */
      74             : static constexpr unsigned int STANDARD_NOT_MANDATORY_VERIFY_FLAGS = STANDARD_SCRIPT_VERIFY_FLAGS & ~MANDATORY_SCRIPT_VERIFY_FLAGS;
      75             : 
      76             : /** Used as the flags parameter to sequence and nLocktime checks in non-consensus code. */
      77             : static constexpr unsigned int STANDARD_LOCKTIME_VERIFY_FLAGS = LOCKTIME_VERIFY_SEQUENCE |
      78             :                                                                LOCKTIME_MEDIAN_TIME_PAST;
      79             : 
      80             : CAmount GetDustThreshold(const CTxOut& txout, const CFeeRate& dustRelayFee);
      81             : 
      82             : bool IsDust(const CTxOut& txout, const CFeeRate& dustRelayFee);
      83             : 
      84             : bool IsStandard(const CScript& scriptPubKey, TxoutType& whichType);
      85             :     /**
      86             :      * Check for standard transaction types
      87             :      * @return True if all outputs (scriptPubKeys) use only standard transaction forms
      88             :      */
      89             : bool IsStandardTx(const CTransaction& tx, bool permit_bare_multisig, const CFeeRate& dust_relay_fee, std::string& reason);
      90             :     /**
      91             :      * Check for standard transaction types
      92             :      * @param[in] mapInputs    Map of previous transactions that have outputs we're spending
      93             :      * @return True if all inputs (scriptSigs) use only standard transaction forms
      94             :      */
      95             : bool AreInputsStandard(const CTransaction& tx, const CCoinsViewCache& mapInputs);
      96             :     /**
      97             :      * Check if the transaction is over standard P2WSH resources limit:
      98             :      * 3600bytes witnessScript size, 80bytes per witness stack element, 100 witness stack elements
      99             :      * These limits are adequate for multi-signature up to n-of-100 using OP_CHECKSIG, OP_ADD, and OP_EQUAL,
     100             :      */
     101             : bool IsWitnessStandard(const CTransaction& tx, const CCoinsViewCache& mapInputs);
     102             : 
     103             : /** Compute the virtual transaction size (weight reinterpreted as bytes). */
     104             : int64_t GetVirtualTransactionSize(int64_t nWeight, int64_t nSigOpCost, unsigned int bytes_per_sigop);
     105             : int64_t GetVirtualTransactionSize(const CTransaction& tx, int64_t nSigOpCost, unsigned int bytes_per_sigop);
     106             : int64_t GetVirtualTransactionInputSize(const CTxIn& tx, int64_t nSigOpCost, unsigned int bytes_per_sigop);
     107             : 
     108       11455 : static inline int64_t GetVirtualTransactionSize(const CTransaction& tx)
     109             : {
     110       11455 :     return GetVirtualTransactionSize(tx, 0, 0);
     111             : }
     112             : 
     113      228428 : static inline int64_t GetVirtualTransactionInputSize(const CTxIn& tx)
     114             : {
     115      228428 :     return GetVirtualTransactionInputSize(tx, 0, 0);
     116             : }
     117             : 
     118             : #endif // BITCOIN_POLICY_POLICY_H