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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server440 file guides

Release published 2026-10-28 · Snapshot fetched 2026-11-01. Latest stable release at fetch time; development branches and Git history are excluded. Only the selected code window and visible folders load here.

32,800 bytes · SHA-256 82e250fadd393b97… · View upstream ↗

1#!/usr/bin/env python3
2# Copyright (c) 2015-present 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"""Functionality to build scripts, as well as signature hash functions.
6
7This file is modified from python-bitcoinlib.
8"""
9
10from collections import namedtuple
11import unittest
12
13from .key import TaggedHash, tweak_add_pubkey, compute_xonly_pubkey
14
15from .messages import (
16    CTransaction,
17    CTxOut,
18    hash256,
19    ser_string,
20    sha256,
21)
22
23from .crypto.ripemd160 import ripemd160
24from .util import assert_equal
25
26MAX_SCRIPT_ELEMENT_SIZE = 520
27MAX_SCRIPT_SIZE = 10000
28MAX_PUBKEYS_PER_MULTI_A = 999
29LOCKTIME_THRESHOLD = 500000000
30ANNEX_TAG = 0x50
31
32SEQUENCE_LOCKTIME_DISABLE_FLAG = (1<<31)
33SEQUENCE_LOCKTIME_TYPE_FLAG = (1<<22) # this means use time (0 means height)
34SEQUENCE_LOCKTIME_GRANULARITY = 9 # this is a bit-shift
35SEQUENCE_LOCKTIME_MASK = 0x0000ffff
36
37LEAF_VERSION_TAPSCRIPT = 0xc0
38
39def hash160(s):
40    return ripemd160(sha256(s))
41
42def bn2vch(v):
43    """Convert number to bitcoin-specific little endian format."""
44    # We need v.bit_length() bits, plus a sign bit for every nonzero number.
45    n_bits = v.bit_length() + (v != 0)
46    # The number of bytes for that is:
47    n_bytes = (n_bits + 7) // 8
48    # Convert number to absolute value + sign in top bit.
49    encoded_v = 0 if v == 0 else abs(v) | ((v < 0) << (n_bytes * 8 - 1))
50    # Serialize to bytes
51    return encoded_v.to_bytes(n_bytes, 'little')
52
53class CScriptOp(int):
54    """A single script opcode"""
55    __slots__ = ()
56
57    @staticmethod
58    def encode_op_pushdata(d):
59        """Encode a PUSHDATA op, returning bytes"""
60        if len(d) < 0x4c:
61            return b'' + bytes([len(d)]) + d  # OP_PUSHDATA
62        elif len(d) <= 0xff:
63            return b'\x4c' + bytes([len(d)]) + d  # OP_PUSHDATA1
64        elif len(d) <= 0xffff:
65            return b'\x4d' + len(d).to_bytes(2, "little") + d  # OP_PUSHDATA2
66        elif len(d) <= 0xffffffff:
67            return b'\x4e' + len(d).to_bytes(4, "little") + d  # OP_PUSHDATA4
68        else:
69            raise ValueError("Data too long to encode in a PUSHDATA op")
70
71    @staticmethod
72    def encode_op_n(n):
73        """Encode a small integer op, returning an opcode"""
74        if not (0 <= n <= 16):
75            raise ValueError('Integer must be in range 0 <= n <= 16, got %d' % n)
76
77        if n == 0:
78            return OP_0
79        else:
80            return CScriptOp(OP_1 + n - 1)
81
82    def decode_op_n(self):
83        """Decode a small integer opcode, returning an integer"""
84        if self == OP_0:
85            return 0
86
87        if not (self == OP_0 or OP_1 <= self <= OP_16):
88            raise ValueError('op %r is not an OP_N' % self)
89
90        return int(self - OP_1 + 1)
91
92    def is_small_int(self):
93        """Return true if the op pushes a small integer to the stack"""
94        if 0x51 <= self <= 0x60 or self == 0:
95            return True
96        else:
97            return False
98
99    def __str__(self):
100        return repr(self)
101
102    def __repr__(self):
103        if self in OPCODE_NAMES:
104            return OPCODE_NAMES[self]
105        else:
106            return 'CScriptOp(0x%x)' % self
107
108    def __new__(cls, n):
109        try:
110            return _opcode_instances[n]
111        except IndexError:
112            assert_equal(len(_opcode_instances), n)
113            _opcode_instances.append(super().__new__(cls, n))
114            return _opcode_instances[n]
115
116OPCODE_NAMES: dict[CScriptOp, str] = {}
117_opcode_instances: list[CScriptOp] = []
118
119# Populate opcode instance table
120for n in range(0xff + 1):
121    CScriptOp(n)
122
123
124# push value
125OP_0 = CScriptOp(0x00)
126OP_FALSE = OP_0
127OP_PUSHDATA1 = CScriptOp(0x4c)
128OP_PUSHDATA2 = CScriptOp(0x4d)
129OP_PUSHDATA4 = CScriptOp(0x4e)
130OP_1NEGATE = CScriptOp(0x4f)
131OP_RESERVED = CScriptOp(0x50)
132OP_1 = CScriptOp(0x51)
133OP_TRUE = OP_1
134OP_2 = CScriptOp(0x52)
135OP_3 = CScriptOp(0x53)
136OP_4 = CScriptOp(0x54)
137OP_5 = CScriptOp(0x55)
138OP_6 = CScriptOp(0x56)
139OP_7 = CScriptOp(0x57)
140OP_8 = CScriptOp(0x58)
141OP_9 = CScriptOp(0x59)
142OP_10 = CScriptOp(0x5a)
143OP_11 = CScriptOp(0x5b)
144OP_12 = CScriptOp(0x5c)
145OP_13 = CScriptOp(0x5d)
146OP_14 = CScriptOp(0x5e)
147OP_15 = CScriptOp(0x5f)
148OP_16 = CScriptOp(0x60)
149
150# control
151OP_NOP = CScriptOp(0x61)
152OP_VER = CScriptOp(0x62)
153OP_IF = CScriptOp(0x63)
154OP_NOTIF = CScriptOp(0x64)
155OP_VERIF = CScriptOp(0x65)
156OP_VERNOTIF = CScriptOp(0x66)
157OP_ELSE = CScriptOp(0x67)
158OP_ENDIF = CScriptOp(0x68)
159OP_VERIFY = CScriptOp(0x69)
160OP_RETURN = CScriptOp(0x6a)
161
162# stack ops
163OP_TOALTSTACK = CScriptOp(0x6b)
164OP_FROMALTSTACK = CScriptOp(0x6c)
165OP_2DROP = CScriptOp(0x6d)
166OP_2DUP = CScriptOp(0x6e)
167OP_3DUP = CScriptOp(0x6f)
168OP_2OVER = CScriptOp(0x70)
169OP_2ROT = CScriptOp(0x71)
170OP_2SWAP = CScriptOp(0x72)
171OP_IFDUP = CScriptOp(0x73)
172OP_DEPTH = CScriptOp(0x74)
173OP_DROP = CScriptOp(0x75)
174OP_DUP = CScriptOp(0x76)
175OP_NIP = CScriptOp(0x77)
176OP_OVER = CScriptOp(0x78)
177OP_PICK = CScriptOp(0x79)
178OP_ROLL = CScriptOp(0x7a)
179OP_ROT = CScriptOp(0x7b)
180OP_SWAP = CScriptOp(0x7c)
181OP_TUCK = CScriptOp(0x7d)
182
183# splice ops
184OP_CAT = CScriptOp(0x7e)
185OP_SUBSTR = CScriptOp(0x7f)
186OP_LEFT = CScriptOp(0x80)
187OP_RIGHT = CScriptOp(0x81)
188OP_SIZE = CScriptOp(0x82)
189
190# bit logic
191OP_INVERT = CScriptOp(0x83)
192OP_AND = CScriptOp(0x84)
193OP_OR = CScriptOp(0x85)
194OP_XOR = CScriptOp(0x86)
195OP_EQUAL = CScriptOp(0x87)
196OP_EQUALVERIFY = CScriptOp(0x88)
197OP_RESERVED1 = CScriptOp(0x89)
198OP_RESERVED2 = CScriptOp(0x8a)
199
200# numeric
201OP_1ADD = CScriptOp(0x8b)
202OP_1SUB = CScriptOp(0x8c)
203OP_2MUL = CScriptOp(0x8d)
204OP_2DIV = CScriptOp(0x8e)
205OP_NEGATE = CScriptOp(0x8f)
206OP_ABS = CScriptOp(0x90)
207OP_NOT = CScriptOp(0x91)
208OP_0NOTEQUAL = CScriptOp(0x92)
209
210OP_ADD = CScriptOp(0x93)
211OP_SUB = CScriptOp(0x94)
212OP_MUL = CScriptOp(0x95)
213OP_DIV = CScriptOp(0x96)
214OP_MOD = CScriptOp(0x97)
215OP_LSHIFT = CScriptOp(0x98)
216OP_RSHIFT = CScriptOp(0x99)
217
218OP_BOOLAND = CScriptOp(0x9a)
219OP_BOOLOR = CScriptOp(0x9b)
220OP_NUMEQUAL = CScriptOp(0x9c)
221OP_NUMEQUALVERIFY = CScriptOp(0x9d)
222OP_NUMNOTEQUAL = CScriptOp(0x9e)
223OP_LESSTHAN = CScriptOp(0x9f)
224OP_GREATERTHAN = CScriptOp(0xa0)
225OP_LESSTHANOREQUAL = CScriptOp(0xa1)
226OP_GREATERTHANOREQUAL = CScriptOp(0xa2)
227OP_MIN = CScriptOp(0xa3)
228OP_MAX = CScriptOp(0xa4)
229
230OP_WITHIN = CScriptOp(0xa5)
231
232# crypto
233OP_RIPEMD160 = CScriptOp(0xa6)
234OP_SHA1 = CScriptOp(0xa7)
235OP_SHA256 = CScriptOp(0xa8)
236OP_HASH160 = CScriptOp(0xa9)
237OP_HASH256 = CScriptOp(0xaa)
238OP_CODESEPARATOR = CScriptOp(0xab)
239OP_CHECKSIG = CScriptOp(0xac)
240OP_CHECKSIGVERIFY = CScriptOp(0xad)
241OP_CHECKMULTISIG = CScriptOp(0xae)
242OP_CHECKMULTISIGVERIFY = CScriptOp(0xaf)
243
244# expansion
245OP_NOP1 = CScriptOp(0xb0)
246OP_CHECKLOCKTIMEVERIFY = CScriptOp(0xb1)
247OP_CHECKSEQUENCEVERIFY = CScriptOp(0xb2)
248OP_NOP4 = CScriptOp(0xb3)
249OP_NOP5 = CScriptOp(0xb4)
250OP_NOP6 = CScriptOp(0xb5)

src/wallet/receive.cpp

src/wallet/coinselection.cpp

src/consensus/validation.h

src/primitives/transaction.cpp

src/script/descriptor.cpp

src/bitcoin-cli.cpp

src/rpc/blockchain.cpp

src/rpc/rawtransaction.cpp

src/init.cpp

src/crypto/sha256.cpp

src/consensus/merkle.h

src/consensus/tx_check.h

src/consensus/tx_verify.h

src/policy/feerate.h

src/policy/feerate.cpp

src/primitives/transaction_identifier.h

src/chainparamsbase.h

src/chainparamsbase.cpp

src/util/moneystr.cpp

src/crypto/ripemd160.h

src/crypto/sha1.h

src/crypto/sha512.h

src/crypto/hmac_sha256.h

src/crypto/hmac_sha512.h

src/crypto/hmac_sha256.cpp

src/crypto/hmac_sha512.cpp

src/crypto/hkdf_sha256_32.h

src/crypto/hkdf_sha256_32.cpp

src/support/cleanse.h

src/support/cleanse.cpp

src/crypto/siphash.cpp

src/crypto/muhash.h

src/crypto/chacha20.h

src/crypto/poly1305.h

src/crypto/chacha20poly1305.h

src/crypto/chacha20poly1305.cpp

src/util/chaintype.cpp

src/util/obfuscation.h

src/util/byte_units.h

src/util/overflow.h

src/blockencodings.cpp

src/net_permissions.cpp

src/policy/packages.cpp

src/policy/rbf.cpp

src/policy/truc_policy.cpp

src/policy/ephemeral_policy.cpp

src/policy/settings.cpp

src/policy/policy.cpp

src/node/transaction.cpp

src/node/coin.cpp

src/rpc/client.cpp

src/rpc/external_signer.cpp

src/rpc/request.cpp

src/rpc/server_util.cpp

src/rpc/fees.cpp

src/rpc/output_script.cpp

src/rpc/rawtransaction_util.cpp

src/rpc/rawtransaction_util.h

src/rpc/register.h

src/rpc/request.h

src/rpc/server_util.h

src/rpc/protocol.h

src/rpc/server.h

src/rpc/signmessage.cpp

src/rpc/txoutproof.cpp

src/rpc/util.cpp

src/rpc/util.h

src/wallet/rpc/addresses.cpp

src/wallet/rpc/backup.cpp

src/wallet/rpc/coins.cpp

src/wallet/rpc/encrypt.cpp

src/wallet/rpc/signmessage.cpp

src/wallet/rpc/util.cpp

src/wallet/rpc/util.h

src/wallet/coincontrol.cpp

src/wallet/coincontrol.h

src/wallet/context.cpp

src/wallet/context.h

src/wallet/crypter.cpp

src/wallet/crypter.h

src/wallet/db.cpp

src/wallet/export.cpp

src/wallet/external_signer_scriptpubkeyman.cpp

src/wallet/rpc/spend.cpp

src/wallet/rpc/transactions.cpp

src/wallet/rpc/wallet.cpp

src/wallet/feebumper.cpp

src/wallet/feebumper.h

src/index/base.h

src/index/base.cpp

src/index/txindex.h

src/index/txindex.cpp

src/index/txindex_key.h

src/index/txospenderindex.h

src/index/txospenderindex.cpp

src/index/blockfilterindex.h

src/index/blockfilterindex.cpp

src/index/coinstatsindex.h

src/index/coinstatsindex.cpp

src/index/db_key.h

src/index/disktxpos.h

src/kernel/chain.cpp

src/kernel/chain.h

src/kernel/checks.cpp

src/kernel/checks.h

src/kernel/context.cpp

src/kernel/context.h

src/kernel/cs_main.cpp

src/kernel/cs_main.h

src/kernel/disconnected_transactions.cpp

src/kernel/disconnected_transactions.h

src/kernel/mempool_removal_reason.cpp

src/kernel/mempool_removal_reason.h

src/kernel/coinstats.cpp

src/kernel/coinstats.h

src/kernel/chainparams.cpp

src/kernel/chainparams.h

src/wallet/sqlite.cpp

src/wallet/sqlite.h

src/wallet/transaction.cpp

src/wallet/transaction.h

src/wallet/dump.cpp

src/wallet/dump.h

src/wallet/init.cpp

src/wallet/walletutil.cpp

src/wallet/walletutil.h

src/wallet/wallettool.cpp

src/wallet/wallettool.h

src/wallet/export.h

src/wallet/migrate.cpp

src/wallet/migrate.h

src/wallet/db.h

src/wallet/walletdb.cpp

src/wallet/interfaces.cpp

src/wallet/scriptpubkeyman.cpp

src/wallet/scriptpubkeyman.h

src/kernel/bitcoinkernel.cpp

src/kernel/bitcoinkernel.h

src/kernel/bitcoinkernel_wrapper.h

src/node/chainstate.cpp

src/node/chainstate.h

src/node/blockstorage.cpp

src/node/blockstorage.h

src/node/mempool_persist.cpp

src/node/mempool_persist.h

src/node/utxo_snapshot.cpp

src/node/utxo_snapshot.h

src/node/kernel_notifications.cpp

src/node/kernel_notifications.h

src/node/blockmanager_args.cpp

src/kernel/blockmanager_opts.h

src/util/expected.cpp

src/policy/settings.h

src/util/types.h

src/kernel/messagestartchars.h

src/kernel/warning.h

src/util/exception.h

src/common/license_info.h

src/node/coins_view_args.h

src/node/database_args.h

src/util/batchpriority.h

src/util/ui_change_type.h

src/node/coins_view_args.cpp

src/node/peerman_args.h

src/util/serfloat.h

src/node/blockmanager_args.h

src/node/database_args.cpp

src/util/overloaded.h

src/interfaces/types.h

src/node/chainstatemanager_args.h

src/node/minisketchwrapper.h

src/util/macros.h

src/util/syserror.h

src/common/run_command.h

src/util/bytevectorhash.cpp

src/node/mempool_persist_args.cpp

src/util/exec.h

src/util/rbf.h

src/crypto/hex_base.h

src/node/mempool_persist_args.h

src/interfaces/echo.h

src/util/any.h

src/util/batchpriority.cpp

src/util/threadnames.h

src/node/coin.h

src/node/mempool_args.h

src/util/asmap.h

src/util/bytevectorhash.h

src/node/context.cpp

src/util/insert.h

src/util/readwritefile.h

src/node/peerman_args.cpp

src/node/interface_ui.cpp

src/interfaces/handler.h

src/node/mining_args.h

src/util/hasher.cpp

src/common/init.h

src/kernel/mempool_limits.h

src/common/system.h

src/crypto/sha3.h

src/util/threadinterrupt.cpp

src/node/protocol_version.h

src/util/exception.cpp

src/common/messages.h

src/node/connection_types.cpp

src/util/bip32.h

src/common/license_info.cpp

src/util/stdmutex.h

src/common/run_command.cpp

src/util/check.cpp

src/util/golombrice.h

src/node/types.h

src/node/timeoffsets.h

src/util/readwritefile.cpp

src/util/fastrange.h

src/util/signalinterrupt.h

src/util/task_runner.h

src/util/syserror.cpp

src/common/interfaces.cpp

src/common/types.h

src/util/threadinterrupt.h

src/kernel/chainstatemanager_opts.h

src/node/psbt.h

src/policy/ephemeral_policy.h

src/util/trace.h

src/common/url.cpp

src/kernel/mempool_options.h

src/util/serfloat.cpp

src/kernel/notifications_interface.h

src/node/timeoffsets.cpp

src/node/warnings.cpp

src/util/hash_type.h

src/crypto/hex_base.cpp

src/node/eviction.h

src/util/tokenbucket.h

src/crypto/aes.h

src/common/pcp.h

src/util/feefrac.cpp

src/node/transaction.h

src/util/threadnames.cpp

src/common/signmessage.h

src/util/exec.cpp

src/util/signalinterrupt.cpp

src/clientversion.cpp

src/common/signmessage.cpp

src/compat/assumptions.h

src/compat/byteswap.h

src/deploymentinfo.cpp

src/deploymentinfo.h

src/deploymentstatus.cpp

src/deploymentstatus.h

src/dummywallet.cpp

src/external_signer.h

src/init/bitcoin-gui.cpp

src/init/bitcoin-node.cpp

src/init/bitcoin-qt.cpp

src/init/bitcoin-wallet.cpp

src/init/bitcoind.cpp

src/init/common.h

src/interfaces/init.h

src/interfaces/ipc.h

src/key_io.h

src/logging/categories.h

src/logging/timer.h

src/mapport.h

src/musig.h

src/net_permissions.h

src/netgroup.h

src/netmessagemaker.h

src/node/chainstatemanager_args.cpp

src/node/connection_types.h

src/node/context.h

src/node/interface_ui.h

src/node/mempool_args.cpp

src/node/mining_args.cpp

src/node/minisketchwrapper.cpp

src/node/txreconciliation.h

src/policy/fees/estimator_args.cpp

src/policy/fees/estimator_args.h

src/policy/fees/estimator_man.cpp

src/policy/fees/estimator_man.h

src/policy/packages.h

src/policy/rbf.h

src/policy/truc_policy.h

src/pow.h

src/primitives/block.cpp

src/randomenv.h

src/rest.h

src/script/keyorigin.h

src/script/parsing.cpp

src/script/parsing.h

src/script/script_error.h

src/script/sigcache.cpp

src/script/sigcache.h

src/script/solver.h

src/script/verify_flags.h

src/semaphore_grant.h

src/signet.h

src/span.h

src/support/allocators/secure.h

src/support/allocators/zeroafterfree.h

src/util/tokenpipe.cpp

src/util/translation.h

src/util/vector.h

src/versionbits.h

src/versionbits_impl.h

src/wallet/external_signer_scriptpubkeyman.h

src/wallet/fees.h

src/wallet/load.h

src/wallet/receive.h

src/wallet/rpc/wallet.h

src/wallet/types.h

src/walletinitinterface.h

src/zmq/zmqabstractnotifier.cpp

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