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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.

9,254 bytes · SHA-256 986e75b6d7cddc46… · View upstream ↗

1// Copyright (c) 2009-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 <test/fuzz/fuzz.h>
6
7#include <netaddress.h>
8#include <netbase.h>
9#include <test/fuzz/util/check_globals.h>
10#include <test/util/coverage.h>
11#include <test/util/random.h>
12#include <test/util/setup_common.h>
13#include <util/check.h>
14#include <util/fs.h>
15#include <util/sock.h>
16#include <util/time.h>
17
18#include <algorithm>
19#include <csignal>
20#include <cstdint>
21#include <cstdio>
22#include <cstdlib>
23#include <cstring>
24#include <exception>
25#include <fstream>
26#include <functional>
27#include <iostream>
28#include <map>
29#include <memory>
30#include <random>
31#include <string>
32#include <tuple>
33#include <utility>
34#include <vector>
35
36#if defined(PROVIDE_FUZZ_MAIN_FUNCTION) && defined(__AFL_FUZZ_INIT)
37__AFL_FUZZ_INIT();
38#endif
39
40/**
41 * A copy of the command line arguments that start with `--`.
42 * First `LLVMFuzzerInitialize()` is called, which saves the arguments to `g_args`.
43 * Later, depending on the fuzz test, `G_TEST_COMMAND_LINE_ARGUMENTS()` may be
44 * called by `BasicTestingSetup` constructor to fetch those arguments and store
45 * them in `BasicTestingSetup::m_node::args`.
46 */
47static std::vector<const char*> g_args;
48
49static void SetArgs(int argc, char** argv) {
50    for (int i = 1; i < argc; ++i) {
51        // Only take into account arguments that start with `--`. The others are for the fuzz engine:
52        // `fuzz -runs=1 fuzz_corpora/address_deserialize --checkaddrman=5`
53        if (strlen(argv[i]) > 2 && argv[i][0] == '-' && argv[i][1] == '-') {
54            g_args.push_back(argv[i]);
55        }
56    }
57}
58
59const std::function<std::vector<const char*>()> G_TEST_COMMAND_LINE_ARGUMENTS = []() {
60    return g_args;
61};
62
63struct FuzzTarget {
64    const TypeTestOneInput test_one_input;
65    const FuzzTargetOptions opts;
66};
67
68auto& FuzzTargets()
69{
70    static std::map<std::string_view, FuzzTarget> g_fuzz_targets;
71    return g_fuzz_targets;
72}
73
74void FuzzFrameworkRegisterTarget(std::string_view name, TypeTestOneInput target, FuzzTargetOptions opts)
75{
76    const auto [it, ins]{FuzzTargets().try_emplace(name, std::move(target), std::move(opts))};
77    Assert(ins);
78}
79
80static std::string_view g_fuzz_target;
81static const TypeTestOneInput* g_test_one_input{nullptr};
82
83static void test_one_input(FuzzBufferType buffer)
84{
85    CheckGlobals check{};
86    (*Assert(g_test_one_input))(buffer);
87}
88
89const std::function<std::string()> G_TEST_GET_FULL_NAME{[]{
90    return std::string{g_fuzz_target};
91}};
92
93static void initialize()
94{
95    CheckGlobals check{};
96    // By default, make the RNG deterministic with a fixed seed. This will affect all
97    // randomness during the fuzz test, except:
98    // - GetStrongRandBytes(), which is used for the creation of private key material.
99    // - Randomness obtained before this call in g_rng_temp_path_init
100    SeedRandomStateForTest(SeedRand::ZEROS);
101
102    // Set time to the genesis block timestamp for deterministic initialization.
103    SetMockTime(1231006505s);
104
105    // Terminate immediately if a fuzzing harness ever tries to create a socket.
106    // Individual tests can override this by pointing CreateSock to a mocked alternative.
107    CreateSock = [](int, int, int) -> std::unique_ptr<Sock> { std::terminate(); };
108
109    // Terminate immediately if a fuzzing harness ever tries to perform a DNS lookup.
110    g_dns_lookup = [](const std::string& name, bool allow_lookup) {
111        if (allow_lookup) {
112            std::terminate();
113        }
114        return WrappedGetAddrInfo(name, false);
115    };
116
117    bool should_exit{false};
118    if (std::getenv("PRINT_ALL_FUZZ_TARGETS_AND_ABORT")) {
119        for (const auto& [name, t] : FuzzTargets()) {
120            if (t.opts.hidden) continue;
121            std::cout << name << std::endl;
122        }
123        should_exit = true;
124    }
125    if (const char* out_path = std::getenv("WRITE_ALL_FUZZ_TARGETS_AND_ABORT")) {
126        std::cout << "Writing all fuzz target names to '" << out_path << "'." << std::endl;
127        std::ofstream out_stream{out_path, std::ios::binary};
128        for (const auto& [name, t] : FuzzTargets()) {
129            if (t.opts.hidden) continue;
130            out_stream << name << std::endl;
131        }
132        should_exit = true;
133    }
134    if (should_exit) {
135        std::exit(EXIT_SUCCESS);
136    }
137    if (const auto* env_fuzz{std::getenv("FUZZ")}) {
138        // To allow for easier fuzz executable binary modification,
139        static std::string g_copy{env_fuzz}; // create copy to avoid compiler optimizations, and
140        g_fuzz_target = g_copy.c_str();      // strip string after the first null-char.
141    } else {
142        std::cerr << "Must select fuzz target with the FUZZ env var." << std::endl;
143        std::cerr << "Hint: Set the PRINT_ALL_FUZZ_TARGETS_AND_ABORT=1 env var to see all compiled targets." << std::endl;
144        std::exit(EXIT_FAILURE);
145    }
146    const auto it = FuzzTargets().find(g_fuzz_target);
147    if (it == FuzzTargets().end()) {
148        std::cerr << "No fuzz target compiled for " << g_fuzz_target << "." << std::endl;
149        std::exit(EXIT_FAILURE);
150    }
151    if constexpr (!G_FUZZING_BUILD && !G_ABORT_ON_FAILED_ASSUME) {
152        std::cerr << "Must compile with -DBUILD_FOR_FUZZING=ON or in Debug mode to execute a fuzz target." << std::endl;
153        std::exit(EXIT_FAILURE);
154    }
155    if (!EnableFuzzDeterminism()) {
156        if (std::getenv("FUZZ_NONDETERMINISM")) {
157            std::cerr << "Warning: FUZZ_NONDETERMINISM env var set, results may be inconsistent with fuzz build" << std::endl;
158        } else {
159            g_enable_dynamic_fuzz_determinism = true;
160            assert(EnableFuzzDeterminism());
161        }
162    }
163    Assert(!g_test_one_input);
164    g_test_one_input = &it->second.test_one_input;
165    it->second.opts.init();
166
167    ResetCoverageCounters();
168}
169
170#if defined(PROVIDE_FUZZ_MAIN_FUNCTION)
171static bool read_stdin(std::vector<uint8_t>& data)
172{
173    std::istream::char_type buffer[1024];
174    std::streamsize length;
175    while ((std::cin.read(buffer, 1024), length = std::cin.gcount()) > 0) {
176        data.insert(data.end(), buffer, buffer + length);
177    }
178    return length == 0;
179}
180#endif
181
182#if defined(PROVIDE_FUZZ_MAIN_FUNCTION) && !defined(__AFL_LOOP)
183static bool read_file(fs::path p, std::vector<uint8_t>& data)
184{
185    uint8_t buffer[1024];
186    FILE* f = fsbridge::fopen(p, "rb");
187    if (f == nullptr) return false;
188    do {
189        const size_t length = fread(buffer, sizeof(uint8_t), sizeof(buffer), f);
190        if (ferror(f)) return false;
191        data.insert(data.end(), buffer, buffer + length);
192    } while (!feof(f));
193    fclose(f);
194    return true;
195}
196#endif
197
198#if defined(PROVIDE_FUZZ_MAIN_FUNCTION) && !defined(__AFL_LOOP)
199static fs::path g_input_path;
200void signal_handler(int signal)
201{
202    if (signal == SIGABRT) {
203        std::cerr << "Error processing input " << g_input_path << std::endl;
204    } else {
205        std::cerr << "Unexpected signal " << signal << " received\n";
206    }
207    std::_Exit(EXIT_FAILURE);
208}
209#endif
210
211// This function is used by libFuzzer
212extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size)
213{
214    test_one_input({data, size});
215    return 0;
216}
217
218// This function is used by libFuzzer
219extern "C" int LLVMFuzzerInitialize(int* argc, char*** argv)
220{
221    SetArgs(*argc, *argv);
222    initialize();
223    return 0;
224}
225
226#if defined(PROVIDE_FUZZ_MAIN_FUNCTION)
227int main(int argc, char** argv)
228{
229    initialize();
230#ifdef __AFL_LOOP
231    // Enable AFL persistent mode. Requires compilation using afl-clang-fast++.
232    // See fuzzing.md for details.
233    const uint8_t* buffer = __AFL_FUZZ_TESTCASE_BUF;
234    while (__AFL_LOOP(100'000)) {
235        size_t buffer_len = __AFL_FUZZ_TESTCASE_LEN;
236        test_one_input({buffer, buffer_len});
237    }
238#else
239    std::vector<uint8_t> buffer;
240    if (argc <= 1) {
241        if (!read_stdin(buffer)) {
242            return 0;
243        }
244        test_one_input(buffer);
245        return 0;
246    }
247    std::signal(SIGABRT, signal_handler);
248    const auto start_time{Now<SteadySeconds>()};
249    int tested = 0;
250    for (int i = 1; i < argc; ++i) {

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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