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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.

9,626 bytes · SHA-256 93f0ae0a31eb4039… · View upstream ↗

1#!/usr/bin/env python3
2# Copyright (c) 2026-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"""Base classes for creating dynamic xprvs and xpubs. Only basic
6functionality of BIP32 is provided here. These classes work over
7the ECKey and ECPubKey classes in the key.py."""
8
9import hashlib
10import hmac
11import unittest
12
13from test_framework.address import byte_to_base58
14from test_framework.crypto import secp256k1
15from test_framework.key import (
16    ECKey,
17    ECPubKey,
18    generate_privkey,
19    ORDER,
20)
21from test_framework.script import hash160
22
23BIP32_HARDENED = 0x80000000
24
25def get_version(private=False, mainnet=False):
26    if mainnet:
27        if private:
28            return bytes.fromhex("0488ADE4")
29        return bytes.fromhex("0488B21E")
30
31    if private:
32        return bytes.fromhex("04358394")
33    return bytes.fromhex("043587CF")
34
35def hardened(index):
36    assert 0 <= index < BIP32_HARDENED
37    return index | BIP32_HARDENED
38
39def derive_path(key, path, path_idx_parser):
40    if path in ("", "m"):
41        return key
42    parts = path.split("/")
43    if parts[0] == "m":
44        parts = parts[1:]
45    for part in parts:
46        index = path_idx_parser(part)
47        key = key._derive(index)
48
49    return key
50
51class ExtendedPrivateKey:
52    def __init__(self, key, chaincode, depth=0, parent_fingerprint_bytes=b"\x00\x00\x00\x00", child_num=0):
53        self.key = key
54        self.chaincode = chaincode
55        self.depth = depth
56        self.parent_fingerprint_bytes = parent_fingerprint_bytes
57        self.child_num = child_num
58
59    @classmethod
60    def from_seed(cls, seed):
61        I = hmac.new(b"Bitcoin seed", seed, hashlib.sha512).digest()
62
63        secret = I[:32]
64        chaincode = I[32:]
65
66        secret_int = int.from_bytes(secret, "big")
67        if secret_int == 0 or secret_int >= ORDER:
68            raise ValueError("Invalid master key")
69
70        key = ECKey()
71        key.set(secret, compressed=True)
72
73        return cls(key, chaincode)
74
75    @classmethod
76    def generate(cls):
77        return cls.from_seed(generate_privkey())
78
79    def _fingerprint(self):
80        return hash160(self.key.get_pubkey().get_bytes())[:4]
81
82    def _derive(self, index):
83        if index >= BIP32_HARDENED:
84            data = (b"\x00" + self.key.get_bytes() + index.to_bytes(4, "big"))
85        else:
86            data = (self.key.get_pubkey().get_bytes() + index.to_bytes(4, "big"))
87
88        I = hmac.new(self.chaincode, data, hashlib.sha512).digest()
89        IL = I[:32]
90        IR = I[32:]
91
92        IL_int = int.from_bytes(IL, "big")
93        child_secret = (IL_int + int.from_bytes(self.key.get_bytes(), "big")) % ORDER
94        # Per BIP32, if IL >= n or the child key is 0, the key is invalid. This is
95        # astronomically unlikely (~1 in 2^127), so reject rather than retrying the next index.
96        if IL_int >= ORDER or child_secret == 0:
97            raise ValueError("Invalid BIP32 child key")
98
99        child = ECKey()
100        child.set(child_secret.to_bytes(32, 'big'), compressed=True)
101
102        return ExtendedPrivateKey(child, IR, self.depth + 1, self._fingerprint(), index)
103
104    def _serialize(self):
105        return (bytes([self.depth]) + self.parent_fingerprint_bytes + self.child_num.to_bytes(4, "big") + self.chaincode + b"\x00" + self.key.get_bytes())
106
107    def pubkey(self):
108        return ExtendedPublicKey(self.key.get_pubkey(), self.chaincode, self.depth, self.parent_fingerprint_bytes, self.child_num)
109
110    def derive_path(self, path):
111        def path_idx_parser(part):
112            if part.endswith(("h", "'")):
113                return hardened(int(part[:-1]))
114            return int(part)
115
116        return derive_path(self, path, path_idx_parser)
117
118    def to_string(self, mainnet=False):
119        return byte_to_base58(self._serialize(), get_version(private=True, mainnet=mainnet))
120
121class ExtendedPublicKey:
122    def __init__(self, pubkey, chaincode, depth, parent_fingerprint_bytes, child_num):
123        self.pubkey = pubkey
124        self.chaincode = chaincode
125        self.depth = depth
126        self.parent_fingerprint_bytes = parent_fingerprint_bytes
127        self.child_num = child_num
128
129    def _fingerprint(self):
130        return hash160(self.pubkey.get_bytes())[:4]
131
132    def _derive(self, index):
133        if index >= BIP32_HARDENED:
134            raise ValueError("Cannot derive hardened child from xpub")
135
136        data = (self.pubkey.get_bytes() + index.to_bytes(4, "big"))
137        I = hmac.new(self.chaincode, data, hashlib.sha512).digest()
138        IL = I[:32]
139        IR = I[32:]
140
141        IL_int = int.from_bytes(IL, "big")
142        child_point = IL_int * secp256k1.G + self.pubkey.p
143        # Per BIP32, if IL >= n or the resulting point is infinity, the key is invalid.
144        if IL_int >= ORDER or child_point.infinity:
145            raise ValueError("Invalid BIP32 child key")
146
147        child_pubkey = ECPubKey()
148        child_pubkey.set(child_point.to_bytes_compressed())
149
150        return ExtendedPublicKey(child_pubkey, IR, self.depth + 1, self._fingerprint(), index)
151
152    def _serialize(self):
153        return (bytes([self.depth]) + self.parent_fingerprint_bytes + self.child_num.to_bytes(4, "big") + self.chaincode + self.pubkey.get_bytes())
154
155    def derive_path(self, path):
156        return derive_path(self, path, lambda x: int(x))
157
158    def to_string(self, mainnet=False):
159        return byte_to_base58(self._serialize(), get_version(private=False, mainnet=mainnet))
160
161class TestFrameworkExtendedKey(unittest.TestCase):
162    def test_bip32_vectors(self):
163        vectors = [
164            [
165                "000102030405060708090a0b0c0d0e0f",
166                [
167                    ["m", "xprv9s21ZrQH143K3QTDL4LXw2F7HEK3wJUD2nW2nRk4stbPy6cq3jPPqjiChkVvvNKmPGJxWUtg6LnF5kejMRNNU3TGtRBeJgk33yuGBxrMPHi", "xpub661MyMwAqRbcFtXgS5sYJABqqG9YLmC4Q1Rdap9gSE8NqtwybGhePY2gZ29ESFjqJoCu1Rupje8YtGqsefD265TMg7usUDFdp6W1EGMcet8"],
168                    ["m/0h", "xprv9uHRZZhk6KAJC1avXpDAp4MDc3sQKNxDiPvvkX8Br5ngLNv1TxvUxt4cV1rGL5hj6KCesnDYUhd7oWgT11eZG7XnxHrnYeSvkzY7d2bhkJ7", "xpub68Gmy5EdvgibQVfPdqkBBCHxA5htiqg55crXYuXoQRKfDBFA1WEjWgP6LHhwBZeNK1VTsfTFUHCdrfp1bgwQ9xv5ski8PX9rL2dZXvgGDnw"],
169                    ["m/0h/1", "xprv9wTYmMFdV23N2TdNG573QoEsfRrWKQgWeibmLntzniatZvR9BmLnvSxqu53Kw1UmYPxLgboyZQaXwTCg8MSY3H2EU4pWcQDnRnrVA1xe8fs", "xpub6ASuArnXKPbfEwhqN6e3mwBcDTgzisQN1wXN9BJcM47sSikHjJf3UFHKkNAWbWMiGj7Wf5uMash7SyYq527Hqck2AxYysAA7xmALppuCkwQ"],
170                    ["m/0h/1/2h", "xprv9z4pot5VBttmtdRTWfWQmoH1taj2axGVzFqSb8C9xaxKymcFzXBDptWmT7FwuEzG3ryjH4ktypQSAewRiNMjANTtpgP4mLTj34bhnZX7UiM", "xpub6D4BDPcP2GT577Vvch3R8wDkScZWzQzMMUm3PWbmWvVJrZwQY4VUNgqFJPMM3No2dFDFGTsxxpG5uJh7n7epu4trkrX7x7DogT5Uv6fcLW5"],
171                    ["m/0h/1/2h/2", "xprvA2JDeKCSNNZky6uBCviVfJSKyQ1mDYahRjijr5idH2WwLsEd4Hsb2Tyh8RfQMuPh7f7RtyzTtdrbdqqsunu5Mm3wDvUAKRHSC34sJ7in334", "xpub6FHa3pjLCk84BayeJxFW2SP4XRrFd1JYnxeLeU8EqN3vDfZmbqBqaGJAyiLjTAwm6ZLRQUMv1ZACTj37sR62cfN7fe5JnJ7dh8zL4fiyLHV"],
172                    ["m/0h/1/2h/2/1000000000", "xprvA41z7zogVVwxVSgdKUHDy1SKmdb533PjDz7J6N6mV6uS3ze1ai8FHa8kmHScGpWmj4WggLyQjgPie1rFSruoUihUZREPSL39UNdE3BBDu76", "xpub6H1LXWLaKsWFhvm6RVpEL9P4KfRZSW7abD2ttkWP3SSQvnyA8FSVqNTEcYFgJS2UaFcxupHiYkro49S8yGasTvXEYBVPamhGW6cFJodrTHy"],
173                ]
174            ],
175            [
176                "fffcf9f6f3f0edeae7e4e1dedbd8d5d2cfccc9c6c3c0bdbab7b4b1aeaba8a5a29f9c999693908d8a8784817e7b7875726f6c696663605d5a5754514e4b484542",
177                [
178                    ["m", "xprv9s21ZrQH143K31xYSDQpPDxsXRTUcvj2iNHm5NUtrGiGG5e2DtALGdso3pGz6ssrdK4PFmM8NSpSBHNqPqm55Qn3LqFtT2emdEXVYsCzC2U", "xpub661MyMwAqRbcFW31YEwpkMuc5THy2PSt5bDMsktWQcFF8syAmRUapSCGu8ED9W6oDMSgv6Zz8idoc4a6mr8BDzTJY47LJhkJ8UB7WEGuduB"],
179                    ["m/0", "xprv9vHkqa6EV4sPZHYqZznhT2NPtPCjKuDKGY38FBWLvgaDx45zo9WQRUT3dKYnjwih2yJD9mkrocEZXo1ex8G81dwSM1fwqWpWkeS3v86pgKt", "xpub69H7F5d8KSRgmmdJg2KhpAK8SR3DjMwAdkxj3ZuxV27CprR9LgpeyGmXUbC6wb7ERfvrnKZjXoUmmDznezpbZb7ap6r1D3tgFxHmwMkQTPH"],
180                    ["m/0/2147483647h", "xprv9wSp6B7kry3Vj9m1zSnLvN3xH8RdsPP1Mh7fAaR7aRLcQMKTR2vidYEeEg2mUCTAwCd6vnxVrcjfy2kRgVsFawNzmjuHc2YmYRmagcEPdU9", "xpub6ASAVgeehLbnwdqV6UKMHVzgqAG8Gr6riv3Fxxpj8ksbH9ebxaEyBLZ85ySDhKiLDBrQSARLq1uNRts8RuJiHjaDMBU4Zn9h8LZNnBC5y4a"],
181                    ["m/0/2147483647h/1", "xprv9zFnWC6h2cLgpmSA46vutJzBcfJ8yaJGg8cX1e5StJh45BBciYTRXSd25UEPVuesF9yog62tGAQtHjXajPPdbRCHuWS6T8XA2ECKADdw4Ef", "xpub6DF8uhdarytz3FWdA8TvFSvvAh8dP3283MY7p2V4SeE2wyWmG5mg5EwVvmdMVCQcoNJxGoWaU9DCWh89LojfZ537wTfunKau47EL2dhHKon"],
182                    ["m/0/2147483647h/1/2147483646h", "xprvA1RpRA33e1JQ7ifknakTFpgNXPmW2YvmhqLQYMmrj4xJXXWYpDPS3xz7iAxn8L39njGVyuoseXzU6rcxFLJ8HFsTjSyQbLYnMpCqE2VbFWc", "xpub6ERApfZwUNrhLCkDtcHTcxd75RbzS1ed54G1LkBUHQVHQKqhMkhgbmJbZRkrgZw4koxb5JaHWkY4ALHY2grBGRjaDMzQLcgJvLJuZZvRcEL"],
183                    ["m/0/2147483647h/1/2147483646h/2", "xprvA2nrNbFZABcdryreWet9Ea4LvTJcGsqrMzxHx98MMrotbir7yrKCEXw7nadnHM8Dq38EGfSh6dqA9QWTyefMLEcBYJUuekgW4BYPJcr9E7j", "xpub6FnCn6nSzZAw5Tw7cgR9bi15UV96gLZhjDstkXXxvCLsUXBGXPdSnLFbdpq8p9HmGsApME5hQTZ3emM2rnY5agb9rXpVGyy3bdW6EEgAtqt"]
184                ]
185            ]
186        ]
187
188        for vector in vectors:
189            seed = bytes.fromhex(vector[0])
190            xprv = ExtendedPrivateKey.from_seed(seed)
191            for seed_vector in vector[1]:
192                path = seed_vector[0]
193                derivedxprv = xprv.derive_path(path)
194                self.assertEqual(derivedxprv.to_string(mainnet=True), seed_vector[1])
195                self.assertEqual(derivedxprv.pubkey().to_string(mainnet=True), seed_vector[2])
196

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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