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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.

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1// Copyright (c) 2021-present The Bitcoin Core developers
2// Distributed under the MIT software license, see the accompanying
3// file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5#include <consensus/amount.h>
6#include <pubkey.h>
7#include <test/fuzz/util.h>
8#include <test/util/script.h>
9#include <util/check.h>
10#include <util/overflow.h>
11#include <util/rbf.h>
12#include <util/time.h>
13
14#include <memory>
15
16std::vector<uint8_t> ConstructPubKeyBytes(FuzzedDataProvider& fuzzed_data_provider, std::span<const uint8_t> byte_data, const bool compressed) noexcept
17{
18    uint8_t pk_type;
19    if (compressed) {
20        pk_type = fuzzed_data_provider.PickValueInArray({0x02, 0x03});
21    } else {
22        pk_type = fuzzed_data_provider.PickValueInArray({0x04, 0x06, 0x07});
23    }
24    std::vector<uint8_t> pk_data{byte_data.begin(), byte_data.begin() + (compressed ? CPubKey::COMPRESSED_SIZE : CPubKey::SIZE)};
25    pk_data[0] = pk_type;
26    return pk_data;
27}
28
29CAmount ConsumeMoney(FuzzedDataProvider& fuzzed_data_provider, const std::optional<CAmount>& max) noexcept
30{
31    return fuzzed_data_provider.ConsumeIntegralInRange<CAmount>(0, max.value_or(MAX_MONEY));
32}
33
34NodeSeconds ConsumeTime(FuzzedDataProvider& fuzzed_data_provider, const std::optional<int64_t>& min, const std::optional<int64_t>& max) noexcept
35{
36    // Avoid t=0 (1970-01-01T00:00:00Z) since SetMockTime(0) disables mocktime.
37    static const int64_t time_min{ParseISO8601DateTime("2000-01-01T00:00:01Z").value()};
38    static const int64_t time_max{ParseISO8601DateTime("2100-12-31T23:59:59Z").value()};
39    return NodeSeconds{ConsumeDuration<std::chrono::seconds>(fuzzed_data_provider, min.value_or(time_min) * 1s, max.value_or(time_max) * 1s)};
40}
41
42CMutableTransaction ConsumeTransaction(FuzzedDataProvider& fuzzed_data_provider, const std::optional<std::vector<Txid>>& prevout_txids, const int max_num_in, const int max_num_out) noexcept
43{
44    CMutableTransaction tx_mut;
45    const auto p2wsh_op_true = fuzzed_data_provider.ConsumeBool();
46    tx_mut.version = fuzzed_data_provider.ConsumeBool() ?
47                          CTransaction::CURRENT_VERSION :
48                          fuzzed_data_provider.ConsumeIntegral<uint32_t>();
49    tx_mut.nLockTime = fuzzed_data_provider.ConsumeIntegral<uint32_t>();
50    const auto num_in = fuzzed_data_provider.ConsumeIntegralInRange<int>(0, max_num_in);
51    const auto num_out = fuzzed_data_provider.ConsumeIntegralInRange<int>(0, max_num_out);
52    for (int i = 0; i < num_in; ++i) {
53        const auto& txid_prev = prevout_txids ?
54                                    PickValue(fuzzed_data_provider, *prevout_txids) :
55                                    Txid::FromUint256(ConsumeUInt256(fuzzed_data_provider));
56        const auto index_out = fuzzed_data_provider.ConsumeIntegralInRange<uint32_t>(0, max_num_out);
57        const auto sequence = ConsumeSequence(fuzzed_data_provider);
58        const auto script_sig = p2wsh_op_true ? CScript{} : ConsumeScript(fuzzed_data_provider);
59        CScriptWitness script_wit;
60        if (p2wsh_op_true) {
61            script_wit.stack = std::vector<std::vector<uint8_t>>{WITNESS_STACK_ELEM_OP_TRUE};
62        } else {
63            script_wit = ConsumeScriptWitness(fuzzed_data_provider);
64        }
65        CTxIn in;
66        in.prevout = COutPoint{txid_prev, index_out};
67        in.nSequence = sequence;
68        in.scriptSig = script_sig;
69        in.scriptWitness = script_wit;
70
71        tx_mut.vin.push_back(in);
72    }
73    for (int i = 0; i < num_out; ++i) {
74        const auto amount = fuzzed_data_provider.ConsumeIntegralInRange<CAmount>(-10, 50 * COIN + 10);
75        const auto script_pk = p2wsh_op_true ?
76                                   P2WSH_OP_TRUE :
77                                   ConsumeScript(fuzzed_data_provider, /*maybe_p2wsh=*/true);
78        tx_mut.vout.emplace_back(amount, script_pk);
79    }
80    return tx_mut;
81}
82
83CScriptWitness ConsumeScriptWitness(FuzzedDataProvider& fuzzed_data_provider, const size_t max_stack_elem_size) noexcept
84{
85    CScriptWitness ret;
86    const auto n_elements = fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, max_stack_elem_size);
87    for (size_t i = 0; i < n_elements; ++i) {
88        ret.stack.push_back(ConsumeRandomLengthByteVector(fuzzed_data_provider));
89    }
90    return ret;
91}
92
93CScript ConsumeScript(FuzzedDataProvider& fuzzed_data_provider, const bool maybe_p2wsh) noexcept
94{
95    CScript r_script{};
96    {
97        // Keep a buffer of bytes to allow the fuzz engine to produce smaller
98        // inputs to generate CScripts with repeated data.
99        static constexpr unsigned MAX_BUFFER_SZ{128};
100        std::vector<uint8_t> buffer(MAX_BUFFER_SZ, uint8_t{'a'});
101        while (fuzzed_data_provider.ConsumeBool()) {
102            CallOneOf(
103                fuzzed_data_provider,
104                [&] {
105                    // Insert byte vector directly to allow malformed or unparsable scripts
106                    r_script.insert(r_script.end(), buffer.begin(), buffer.begin() + fuzzed_data_provider.ConsumeIntegralInRange(0U, MAX_BUFFER_SZ));
107                },
108                [&] {
109                    // Push a byte vector from the buffer
110                    r_script << std::vector<uint8_t>{buffer.begin(), buffer.begin() + fuzzed_data_provider.ConsumeIntegralInRange(0U, MAX_BUFFER_SZ)};
111                },
112                [&] {
113                    // Push multisig
114                    // There is a special case for this to aid the fuzz engine
115                    // navigate the highly structured multisig format.
116                    r_script << fuzzed_data_provider.ConsumeIntegralInRange<int64_t>(0, 22);
117                    int num_data{fuzzed_data_provider.ConsumeIntegralInRange(1, 22)};
118                    while (num_data--) {
119                        auto pubkey_bytes{ConstructPubKeyBytes(fuzzed_data_provider, buffer, fuzzed_data_provider.ConsumeBool())};
120                        if (fuzzed_data_provider.ConsumeBool()) {
121                            pubkey_bytes.back() = num_data; // Make each pubkey different
122                        }
123                        r_script << pubkey_bytes;
124                    }
125                    r_script << fuzzed_data_provider.ConsumeIntegralInRange<int64_t>(0, 22);
126                },
127                [&] {
128                    // Mutate the buffer
129                    const auto vec{ConsumeRandomLengthByteVector(fuzzed_data_provider, /*max_length=*/MAX_BUFFER_SZ)};
130                    std::copy(vec.begin(), vec.end(), buffer.begin());
131                },
132                [&] {
133                    // Push an integral
134                    r_script << fuzzed_data_provider.ConsumeIntegral<int64_t>();
135                },
136                [&] {
137                    // Push an opcode
138                    r_script << ConsumeOpcodeType(fuzzed_data_provider);
139                },
140                [&] {
141                    // Push a scriptnum
142                    r_script << ConsumeScriptNum(fuzzed_data_provider);
143                });
144        }
145    }
146    if (maybe_p2wsh && fuzzed_data_provider.ConsumeBool()) {
147        uint256 script_hash;
148        CSHA256().Write(r_script.data(), r_script.size()).Finalize(script_hash.begin());
149        r_script.clear();
150        r_script << OP_0 << ToByteVector(script_hash);
151    }
152    return r_script;
153}
154
155uint32_t ConsumeSequence(FuzzedDataProvider& fuzzed_data_provider) noexcept
156{
157    return fuzzed_data_provider.ConsumeBool() ?
158               fuzzed_data_provider.PickValueInArray({
159                   CTxIn::SEQUENCE_FINAL,
160                   CTxIn::MAX_SEQUENCE_NONFINAL,
161                   MAX_BIP125_RBF_SEQUENCE,
162               }) :
163               fuzzed_data_provider.ConsumeIntegral<uint32_t>();
164}
165
166std::map<COutPoint, Coin> ConsumeCoins(FuzzedDataProvider& fuzzed_data_provider) noexcept
167{
168    std::map<COutPoint, Coin> coins;
169    LIMITED_WHILE (fuzzed_data_provider.ConsumeBool(), 10000) {
170        const std::optional<COutPoint> outpoint{ConsumeDeserializable<COutPoint>(fuzzed_data_provider)};
171        if (!outpoint) {
172            break;
173        }
174        const std::optional<Coin> coin{ConsumeDeserializable<Coin>(fuzzed_data_provider)};
175        if (!coin) {
176            break;
177        }
178        coins[*outpoint] = *coin;
179    }
180
181    return coins;
182}
183
184CTxDestination ConsumeTxDestination(FuzzedDataProvider& fuzzed_data_provider) noexcept
185{
186    CTxDestination tx_destination;
187    const size_t call_size{CallOneOf(
188        fuzzed_data_provider,
189        [&] {
190            tx_destination = CNoDestination{};
191        },
192        [&] {
193            bool compressed = fuzzed_data_provider.ConsumeBool();
194            CPubKey pk{ConstructPubKeyBytes(
195                    fuzzed_data_provider,
196                    ConsumeFixedLengthByteVector(fuzzed_data_provider, (compressed ? CPubKey::COMPRESSED_SIZE : CPubKey::SIZE)),
197                    compressed
198            )};
199            tx_destination = PubKeyDestination{pk};
200        },
201        [&] {
202            tx_destination = PKHash{ConsumeUInt160(fuzzed_data_provider)};
203        },
204        [&] {
205            tx_destination = ScriptHash{ConsumeUInt160(fuzzed_data_provider)};
206        },
207        [&] {
208            tx_destination = WitnessV0ScriptHash{ConsumeUInt256(fuzzed_data_provider)};
209        },
210        [&] {
211            tx_destination = WitnessV0KeyHash{ConsumeUInt160(fuzzed_data_provider)};
212        },
213        [&] {
214            tx_destination = WitnessV1Taproot{XOnlyPubKey{ConsumeUInt256(fuzzed_data_provider)}};
215        },
216        [&] {
217            tx_destination = PayToAnchor{};
218        },
219        [&] {
220            std::vector<unsigned char> program{ConsumeRandomLengthByteVector(fuzzed_data_provider, /*max_length=*/40)};
221            if (program.size() < 2) {
222                program = {0, 0};
223            }
224            tx_destination = WitnessUnknown{fuzzed_data_provider.ConsumeIntegralInRange<unsigned int>(2, 16), program};
225        })};
226    Assert(call_size == std::variant_size_v<CTxDestination>);
227    return tx_destination;
228}
229
230CKey ConsumePrivateKey(FuzzedDataProvider& fuzzed_data_provider, std::optional<bool> compressed) noexcept
231{
232    auto key_data = fuzzed_data_provider.ConsumeBytes<uint8_t>(32);
233    key_data.resize(32);
234    CKey key;
235    bool compressed_value = compressed ? *compressed : fuzzed_data_provider.ConsumeBool();
236    key.Set(key_data.begin(), key_data.end(), compressed_value);
237    return key;
238}
239
240bool ContainsSpentInput(const CTransaction& tx, const CCoinsViewCache& inputs) noexcept
241{
242    for (const CTxIn& tx_in : tx.vin) {
243        const Coin& coin = inputs.AccessCoin(tx_in.prevout);
244        if (coin.IsSpent()) {
245            return true;
246        }
247    }
248    return false;
249}
250

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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