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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) 2020-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 <crypto/chacha20.h>
6#include <random.h>
7#include <test/fuzz/FuzzedDataProvider.h>
8#include <test/fuzz/fuzz.h>
9#include <test/fuzz/util.h>
10
11#include <array>
12#include <cstddef>
13#include <cstdint>
14#include <vector>
15
16FUZZ_TARGET(crypto_chacha20)
17{
18    FuzzedDataProvider fuzzed_data_provider{buffer.data(), buffer.size()};
19
20    const auto key = ConsumeFixedLengthByteVector<std::byte>(fuzzed_data_provider, ChaCha20::KEYLEN);
21    ChaCha20 chacha20{key};
22
23    LIMITED_WHILE (fuzzed_data_provider.ConsumeBool(), 10000) {
24        CallOneOf(
25            fuzzed_data_provider,
26            [&] {
27                auto key = ConsumeFixedLengthByteVector<std::byte>(fuzzed_data_provider, ChaCha20::KEYLEN);
28                chacha20.SetKey(key);
29            },
30            [&] {
31                ChaCha20::Nonce96 nonce{
32                    fuzzed_data_provider.ConsumeIntegral<uint32_t>(),
33                    fuzzed_data_provider.ConsumeIntegral<uint64_t>()};
34                chacha20.Seek(nonce, fuzzed_data_provider.ConsumeIntegral<uint32_t>());
35            },
36            [&] {
37                std::vector<uint8_t> output(fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, 4096));
38                chacha20.Keystream(MakeWritableByteSpan(output));
39            },
40            [&] {
41                std::vector<std::byte> output(fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, 4096));
42                const auto input = ConsumeFixedLengthByteVector<std::byte>(fuzzed_data_provider, output.size());
43                chacha20.Crypt(input, output);
44            });
45    }
46}
47
48namespace
49{
50
51/** Fuzzer that invokes ChaCha20::Crypt() or ChaCha20::Keystream multiple times:
52    once for a large block at once, and then the same data in chunks, comparing
53    the outcome.
54
55    If UseCrypt, seeded InsecureRandomContext output is used as input to Crypt().
56    If not, Keystream() is used directly, or sequences of 0x00 are encrypted.
57*/
58template<bool UseCrypt>
59void ChaCha20SplitFuzz(FuzzedDataProvider& provider)
60{
61    // Determine key, iv, start position, length.
62    auto key_bytes = ConsumeFixedLengthByteVector<std::byte>(provider, ChaCha20::KEYLEN);
63    uint64_t iv = provider.ConsumeIntegral<uint64_t>();
64    uint32_t iv_prefix = provider.ConsumeIntegral<uint32_t>();
65    uint64_t total_bytes = provider.ConsumeIntegralInRange<uint64_t>(0, 1000000);
66    /* ~x = 2^BITS - 1 - x, so ~(total_bytes >> 6) is the maximal seek position. */
67    uint32_t seek = provider.ConsumeIntegralInRange<uint32_t>(0, ~(uint32_t)(total_bytes >> 6));
68
69    // Initialize two ChaCha20 ciphers, with the same key/iv/position.
70    ChaCha20 crypt1(key_bytes);
71    ChaCha20 crypt2(key_bytes);
72    crypt1.Seek({iv_prefix, iv}, seek);
73    crypt2.Seek({iv_prefix, iv}, seek);
74
75    // Construct vectors with data.
76    std::vector<std::byte> data1, data2;
77    data1.resize(total_bytes);
78    data2.resize(total_bytes);
79
80    // If using Crypt(), initialize data1 and data2 with the same InsecureRandomContext based
81    // stream.
82    if constexpr (UseCrypt) {
83        InsecureRandomContext(provider.ConsumeIntegral<uint64_t>()).fillrand(data1);
84        std::copy(data1.begin(), data1.end(), data2.begin());
85    }
86
87    // Whether UseCrypt is used or not, the two byte arrays must match.
88    assert(data1 == data2);
89
90    // Encrypt data1, the whole array at once.
91    if constexpr (UseCrypt) {
92        crypt1.Crypt(data1, data1);
93    } else {
94        crypt1.Keystream(data1);
95    }
96
97    // Encrypt data2, in at most 256 chunks.
98    uint64_t bytes2 = 0;
99    int iter = 0;
100    while (true) {
101        bool is_last = (iter == 255) || (bytes2 == total_bytes) || provider.ConsumeBool();
102        ++iter;
103        // Determine how many bytes to encrypt in this chunk: a fuzzer-determined
104        // amount for all but the last chunk (which processes all remaining bytes).
105        uint64_t now = is_last ? total_bytes - bytes2 :
106            provider.ConsumeIntegralInRange<uint64_t>(0, total_bytes - bytes2);
107        // For each chunk, consider using Crypt() even when UseCrypt is false.
108        // This tests that Keystream() has the same behavior as Crypt() applied
109        // to 0x00 input bytes.
110        if (UseCrypt || provider.ConsumeBool()) {
111            crypt2.Crypt(std::span{data2}.subspan(bytes2, now), std::span{data2}.subspan(bytes2, now));
112        } else {
113            crypt2.Keystream(std::span{data2}.subspan(bytes2, now));
114        }
115        bytes2 += now;
116        if (is_last) break;
117    }
118    // We should have processed everything now.
119    assert(bytes2 == total_bytes);
120    // And the result should match.
121    assert(data1 == data2);
122}
123
124} // namespace
125
126FUZZ_TARGET(chacha20_split_crypt)
127{
128    FuzzedDataProvider provider{buffer.data(), buffer.size()};
129    ChaCha20SplitFuzz<true>(provider);
130}
131
132FUZZ_TARGET(chacha20_split_keystream)
133{
134    FuzzedDataProvider provider{buffer.data(), buffer.size()};
135    ChaCha20SplitFuzz<false>(provider);
136}
137
138FUZZ_TARGET(crypto_fschacha20)
139{
140    FuzzedDataProvider fuzzed_data_provider{buffer.data(), buffer.size()};
141
142    auto key = fuzzed_data_provider.ConsumeBytes<std::byte>(FSChaCha20::KEYLEN);
143    key.resize(FSChaCha20::KEYLEN);
144
145    auto fsc20 = FSChaCha20{key, fuzzed_data_provider.ConsumeIntegralInRange<uint32_t>(1, 1024)};
146
147    LIMITED_WHILE (fuzzed_data_provider.ConsumeBool(), 10000) {
148        auto input = fuzzed_data_provider.ConsumeBytes<std::byte>(fuzzed_data_provider.ConsumeIntegralInRange(0, 4096));
149        std::vector<std::byte> output;
150        output.resize(input.size());
151        fsc20.Crypt(input, output);
152    }
153}
154

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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