1 // Copyright (c) 2009-2010 Satoshi Nakamoto
2 // Copyright (c) 2009-2016 The Bitcoin 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 "script/interpreter.h"
11 #include "script/standard.h"
12 
13 #include <string>
14 
15 class CCoinsViewCache;
16 
17 /** Default for -blockmaxsize, which controls the maximum size of block the mining code will create **/
18 static const unsigned int DEFAULT_BLOCK_MAX_SIZE = 750000;
19 /** Default for -blockprioritysize, maximum space for zero/low-fee transactions **/
20 static const unsigned int DEFAULT_BLOCK_PRIORITY_SIZE = 0;
21 /** Default for -blockmaxweight, which controls the range of block weights the mining code will create **/
22 static const unsigned int DEFAULT_BLOCK_MAX_WEIGHT = 3000000;
23 /** The maximum weight for transactions we're willing to relay/mine */
24 static const unsigned int MAX_STANDARD_TX_WEIGHT = 400000;
25 /** Maximum number of signature check operations in an IsStandard() P2SH script */
26 static const unsigned int MAX_P2SH_SIGOPS = 15;
27 /** The maximum number of sigops we're willing to relay/mine in a single tx */
28 static const unsigned int MAX_STANDARD_TX_SIGOPS_COST = MAX_BLOCK_SIGOPS_COST/5;
29 /** Default for -maxmempool, maximum megabytes of mempool memory usage */
30 static const unsigned int DEFAULT_MAX_MEMPOOL_SIZE = 300;
31 /** Default for -bytespersigop */
32 static const unsigned int DEFAULT_BYTES_PER_SIGOP = 20;
33 /** The maximum number of witness stack items in a standard P2WSH script */
34 static const unsigned int MAX_STANDARD_P2WSH_STACK_ITEMS = 100;
35 /** The maximum size of each witness stack item in a standard P2WSH script */
36 static const unsigned int MAX_STANDARD_P2WSH_STACK_ITEM_SIZE = 80;
37 /** The maximum size of a standard witnessScript */
38 static const unsigned int MAX_STANDARD_P2WSH_SCRIPT_SIZE = 3600;
39 /**
40  * Standard script verification flags that standard transactions will comply
41  * with. However scripts violating these flags may still be present in valid
42  * blocks and we must accept those blocks.
43  */
44 static const unsigned int STANDARD_SCRIPT_VERIFY_FLAGS = MANDATORY_SCRIPT_VERIFY_FLAGS |
45                                                          SCRIPT_VERIFY_DERSIG |
46                                                          SCRIPT_VERIFY_STRICTENC |
47                                                          SCRIPT_VERIFY_MINIMALDATA |
48                                                          SCRIPT_VERIFY_NULLDUMMY |
49                                                          SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_NOPS |
50                                                          SCRIPT_VERIFY_CLEANSTACK |
51                                                          SCRIPT_VERIFY_MINIMALIF |
52                                                          SCRIPT_VERIFY_NULLFAIL |
53                                                          SCRIPT_VERIFY_CHECKLOCKTIMEVERIFY |
54                                                          SCRIPT_VERIFY_CHECKSEQUENCEVERIFY |
55                                                          SCRIPT_VERIFY_LOW_S |
56                                                          SCRIPT_VERIFY_WITNESS |
57                                                          SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_WITNESS_PROGRAM |
58                                                          SCRIPT_VERIFY_WITNESS_PUBKEYTYPE;
59 
60 /** For convenience, standard but not mandatory verify flags. */
61 static const unsigned int STANDARD_NOT_MANDATORY_VERIFY_FLAGS = STANDARD_SCRIPT_VERIFY_FLAGS & ~MANDATORY_SCRIPT_VERIFY_FLAGS;
62 
63 /** Used as the flags parameter to sequence and nLocktime checks in non-consensus code. */
64 static const unsigned int STANDARD_LOCKTIME_VERIFY_FLAGS = LOCKTIME_VERIFY_SEQUENCE |
65                                                            LOCKTIME_MEDIAN_TIME_PAST;
66 
67 bool IsStandard(const CScript& scriptPubKey, txnouttype& whichType, const bool witnessEnabled = false);
68     /**
69      * Check for standard transaction types
70      * @return True if all outputs (scriptPubKeys) use only standard transaction forms
71      */
72 bool IsStandardTx(const CTransaction& tx, std::string& reason, const bool witnessEnabled = false);
73     /**
74      * Check for standard transaction types
75      * @param[in] mapInputs    Map of previous transactions that have outputs we're spending
76      * @return True if all inputs (scriptSigs) use only standard transaction forms
77      */
78 bool AreInputsStandard(const CTransaction& tx, const CCoinsViewCache& mapInputs);
79     /**
80      * Check if the transaction is over standard P2WSH resources limit:
81      * 3600bytes witnessScript size, 80bytes per witness stack element, 100 witness stack elements
82      * These limits are adequate for multi-signature up to n-of-100 using OP_CHECKSIG, OP_ADD, and OP_EQUAL,
83      */
84 bool IsWitnessStandard(const CTransaction& tx, const CCoinsViewCache& mapInputs);
85 
86 extern unsigned int nBytesPerSigOp;
87 
88 /** Compute the virtual transaction size (weight reinterpreted as bytes). */
89 int64_t GetVirtualTransactionSize(int64_t nWeight, int64_t nSigOpCost);
90 int64_t GetVirtualTransactionSize(const CTransaction& tx, int64_t nSigOpCost = 0);
91 
92 #endif // BITCOIN_POLICY_POLICY_H
93