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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.

14,060 bytes · SHA-256 0586a3a92f31d6df… · View upstream ↗

1// Copyright (c) 2009-present The Bitcoin Core developers
2// Copyright (c) 2017 The Zcash 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#include <pubkey.h>
7
8#include <hash.h>
9#include <secp256k1.h>
10#include <secp256k1_ellswift.h>
11#include <secp256k1_extrakeys.h>
12#include <secp256k1_recovery.h>
13#include <secp256k1_schnorrsig.h>
14#include <span.h>
15#include <uint256.h>
16#include <util/strencodings.h>
17
18#include <algorithm>
19#include <cassert>
20
21using namespace util::hex_literals;
22
23namespace {
24
25struct Secp256k1SelfTester
26{
27    Secp256k1SelfTester() {
28        /* Run libsecp256k1 self-test before using the secp256k1_context_static. */
29        secp256k1_selftest();
30    }
31} SECP256K1_SELFTESTER;
32
33} // namespace
34
35/** This function is taken from the libsecp256k1 distribution and implements
36 *  DER parsing for ECDSA signatures, while supporting an arbitrary subset of
37 *  format violations.
38 *
39 *  Supported violations include negative integers, excessive padding, garbage
40 *  at the end, and overly long length descriptors. This is safe to use in
41 *  Bitcoin because since the activation of BIP66, signatures are verified to be
42 *  strict DER before being passed to this module, and we know it supports all
43 *  violations present in the blockchain before that point.
44 */
45int ecdsa_signature_parse_der_lax(secp256k1_ecdsa_signature* sig, const unsigned char *input, size_t inputlen) {
46    size_t rpos, rlen, spos, slen;
47    size_t pos = 0;
48    size_t lenbyte;
49    unsigned char tmpsig[64] = {0};
50    int overflow = 0;
51
52    /* Hack to initialize sig with a correctly-parsed but invalid signature. */
53    secp256k1_ecdsa_signature_parse_compact(secp256k1_context_static, sig, tmpsig);
54
55    /* Sequence tag byte */
56    if (pos == inputlen || input[pos] != 0x30) {
57        return 0;
58    }
59    pos++;
60
61    /* Sequence length bytes */
62    if (pos == inputlen) {
63        return 0;
64    }
65    lenbyte = input[pos++];
66    if (lenbyte & 0x80) {
67        lenbyte -= 0x80;
68        if (lenbyte > inputlen - pos) {
69            return 0;
70        }
71        pos += lenbyte;
72    }
73
74    /* Integer tag byte for R */
75    if (pos == inputlen || input[pos] != 0x02) {
76        return 0;
77    }
78    pos++;
79
80    /* Integer length for R */
81    if (pos == inputlen) {
82        return 0;
83    }
84    lenbyte = input[pos++];
85    if (lenbyte & 0x80) {
86        lenbyte -= 0x80;
87        if (lenbyte > inputlen - pos) {
88            return 0;
89        }
90        while (lenbyte > 0 && input[pos] == 0) {
91            pos++;
92            lenbyte--;
93        }
94        static_assert(sizeof(size_t) >= 4, "size_t too small");
95        if (lenbyte >= 4) {
96            return 0;
97        }
98        rlen = 0;
99        while (lenbyte > 0) {
100            rlen = (rlen << 8) + input[pos];
101            pos++;
102            lenbyte--;
103        }
104    } else {
105        rlen = lenbyte;
106    }
107    if (rlen > inputlen - pos) {
108        return 0;
109    }
110    rpos = pos;
111    pos += rlen;
112
113    /* Integer tag byte for S */
114    if (pos == inputlen || input[pos] != 0x02) {
115        return 0;
116    }
117    pos++;
118
119    /* Integer length for S */
120    if (pos == inputlen) {
121        return 0;
122    }
123    lenbyte = input[pos++];
124    if (lenbyte & 0x80) {
125        lenbyte -= 0x80;
126        if (lenbyte > inputlen - pos) {
127            return 0;
128        }
129        while (lenbyte > 0 && input[pos] == 0) {
130            pos++;
131            lenbyte--;
132        }
133        static_assert(sizeof(size_t) >= 4, "size_t too small");
134        if (lenbyte >= 4) {
135            return 0;
136        }
137        slen = 0;
138        while (lenbyte > 0) {
139            slen = (slen << 8) + input[pos];
140            pos++;
141            lenbyte--;
142        }
143    } else {
144        slen = lenbyte;
145    }
146    if (slen > inputlen - pos) {
147        return 0;
148    }
149    spos = pos;
150
151    /* Ignore leading zeroes in R */
152    while (rlen > 0 && input[rpos] == 0) {
153        rlen--;
154        rpos++;
155    }
156    /* Copy R value */
157    if (rlen > 32) {
158        overflow = 1;
159    } else {
160        memcpy(tmpsig + 32 - rlen, input + rpos, rlen);
161    }
162
163    /* Ignore leading zeroes in S */
164    while (slen > 0 && input[spos] == 0) {
165        slen--;
166        spos++;
167    }
168    /* Copy S value */
169    if (slen > 32) {
170        overflow = 1;
171    } else {
172        memcpy(tmpsig + 64 - slen, input + spos, slen);
173    }
174
175    if (!overflow) {
176        overflow = !secp256k1_ecdsa_signature_parse_compact(secp256k1_context_static, sig, tmpsig);
177    }
178    if (overflow) {
179        /* Overwrite the result again with a correctly-parsed but invalid
180           signature if parsing failed. */
181        memset(tmpsig, 0, 64);
182        secp256k1_ecdsa_signature_parse_compact(secp256k1_context_static, sig, tmpsig);
183    }
184    return 1;
185}
186
187/** Nothing Up My Sleeve (NUMS) point
188 *
189 *  NUMS_H is a point with an unknown discrete logarithm, constructed by taking the sha256 of 'g'
190 *  (uncompressed encoding), which happens to be a point on the curve.
191 *
192 *  For an example script for calculating H, refer to the unit tests in
193 *  ./test/functional/test_framework/crypto/secp256k1.py
194 */
195constexpr XOnlyPubKey XOnlyPubKey::NUMS_H{
196    // Use immediate lambda to work around GCC-14 bug https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117966
197    []() consteval { return XOnlyPubKey{"50929b74c1a04954b78b4b6035e97a5e078a5a0f28ec96d547bfee9ace803ac0"_hex_u8}; }(),
198};
199
200std::vector<CPubKey> XOnlyPubKey::GetCPubKeys() const
201{
202    std::vector<CPubKey> out;
203    unsigned char b[33] = {0x02};
204    std::copy(m_keydata.begin(), m_keydata.end(), b + 1);
205    CPubKey fullpubkey;
206    fullpubkey.Set(b, b + 33);
207    out.push_back(fullpubkey);
208    b[0] = 0x03;
209    fullpubkey.Set(b, b + 33);
210    out.push_back(fullpubkey);
211    return out;
212}
213
214std::vector<CKeyID> XOnlyPubKey::GetKeyIDs() const
215{
216    std::vector<CKeyID> out;
217    for (const CPubKey& pk : GetCPubKeys()) {
218        out.push_back(pk.GetID());
219    }
220    return out;
221}
222
223CPubKey XOnlyPubKey::GetEvenCorrespondingCPubKey() const
224{
225    unsigned char full_key[CPubKey::COMPRESSED_SIZE] = {0x02};
226    std::copy(begin(), end(), full_key + 1);
227    return CPubKey{full_key};
228}
229
230bool XOnlyPubKey::IsFullyValid() const
231{
232    secp256k1_xonly_pubkey pubkey;
233    return secp256k1_xonly_pubkey_parse(secp256k1_context_static, &pubkey, m_keydata.data());
234}
235
236bool XOnlyPubKey::VerifySchnorr(const uint256& msg, std::span<const unsigned char> sigbytes) const
237{
238    assert(sigbytes.size() == 64);
239    secp256k1_xonly_pubkey pubkey;
240    if (!secp256k1_xonly_pubkey_parse(secp256k1_context_static, &pubkey, m_keydata.data())) return false;
241    return secp256k1_schnorrsig_verify(secp256k1_context_static, sigbytes.data(), msg.begin(), 32, &pubkey);
242}
243
244static const HashWriter HASHER_TAPTWEAK{TaggedHash("TapTweak")};
245
246uint256 XOnlyPubKey::ComputeTapTweakHash(const uint256* merkle_root) const
247{
248    if (merkle_root == nullptr) {
249        // We have no scripts. The actual tweak does not matter, but follow BIP341 here to
250        // allow for reproducible tweaking.

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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