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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.

9,055 bytes · SHA-256 5518d666d3c44e43… · View upstream ↗

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/chacha20poly1305.h>
6#include <random.h>
7#include <span.h>
8#include <test/fuzz/FuzzedDataProvider.h>
9#include <test/fuzz/fuzz.h>
10#include <test/fuzz/util.h>
11
12#include <cstddef>
13#include <cstdint>
14#include <vector>
15
16constexpr static inline void crypt_till_rekey(FSChaCha20Poly1305& aead, int rekey_interval, bool encrypt)
17{
18    for (int i = 0; i < rekey_interval; ++i) {
19        std::byte dummy_tag[FSChaCha20Poly1305::EXPANSION] = {{}};
20        if (encrypt) {
21            aead.Encrypt(std::span{dummy_tag}.first(0), std::span{dummy_tag}.first(0), dummy_tag);
22        } else {
23            aead.Decrypt(dummy_tag, std::span{dummy_tag}.first(0), std::span{dummy_tag}.first(0));
24        }
25    }
26}
27
28FUZZ_TARGET(crypto_aeadchacha20poly1305)
29{
30    FuzzedDataProvider provider{buffer.data(), buffer.size()};
31
32    auto key = provider.ConsumeBytes<std::byte>(32);
33    key.resize(32);
34    AEADChaCha20Poly1305 aead(key);
35
36    // Initialize RNG deterministically, to generate contents and AAD. We assume that there are no
37    // (potentially buggy) edge cases triggered by specific values of contents/AAD, so we can avoid
38    // reading the actual data for those from the fuzzer input (which would need large amounts of
39    // data).
40    InsecureRandomContext rng(provider.ConsumeIntegral<uint64_t>());
41
42    LIMITED_WHILE (provider.ConsumeBool(), 100) {
43        // Mode:
44        // - Bit 0: whether to use single-plain Encrypt/Decrypt; otherwise use a split at prefix.
45        // - Bit 2: whether this ciphertext will be corrupted (making it the last sent one)
46        // - Bit 3-4: controls the maximum aad length (max 511 bytes)
47        // - Bit 5-7: controls the maximum content length (max 16383 bytes, for performance reasons)
48        unsigned mode = provider.ConsumeIntegral<uint8_t>();
49        bool use_splits = mode & 1;
50        bool damage = mode & 4;
51        unsigned aad_length_bits = 3 * ((mode >> 3) & 3);
52        unsigned aad_length = provider.ConsumeIntegralInRange<unsigned>(0, (1 << aad_length_bits) - 1);
53        unsigned length_bits = 2 * ((mode >> 5) & 7);
54        unsigned length = provider.ConsumeIntegralInRange<unsigned>(0, (1 << length_bits) - 1);
55        // Generate aad and content.
56        auto aad = rng.randbytes<std::byte>(aad_length);
57        auto plain = rng.randbytes<std::byte>(length);
58        std::vector<std::byte> cipher(length + AEADChaCha20Poly1305::EXPANSION);
59        // Generate nonce
60        AEADChaCha20Poly1305::Nonce96 nonce = {(uint32_t)rng(), rng()};
61
62        if (use_splits && length > 0) {
63            size_t split_index = provider.ConsumeIntegralInRange<size_t>(1, length);
64            aead.Encrypt(std::span{plain}.first(split_index), std::span{plain}.subspan(split_index), aad, nonce, cipher);
65        } else {
66            aead.Encrypt(plain, aad, nonce, cipher);
67        }
68
69        // Test Keystream output
70        std::vector<std::byte> keystream(length);
71        aead.Keystream(nonce, keystream);
72        for (size_t i = 0; i < length; ++i) {
73            assert((plain[i] ^ keystream[i]) == cipher[i]);
74        }
75
76        std::vector<std::byte> decrypted_contents(length);
77        bool ok{false};
78
79        // damage the key
80        unsigned key_position = provider.ConsumeIntegralInRange<unsigned>(0, 31);
81        std::byte damage_val{(uint8_t)(1U << (key_position & 7))};
82        std::vector<std::byte> bad_key = key;
83        bad_key[key_position] ^= damage_val;
84
85        AEADChaCha20Poly1305 bad_aead(bad_key);
86        ok = bad_aead.Decrypt(cipher, aad, nonce, decrypted_contents);
87        assert(!ok);
88
89        // Optionally damage 1 bit in either the cipher (corresponding to a change in transit)
90        // or the aad (to make sure that decryption will fail if the AAD mismatches).
91        if (damage) {
92            unsigned damage_bit = provider.ConsumeIntegralInRange<unsigned>(0, (cipher.size() + aad.size()) * 8U - 1U);
93            unsigned damage_pos = damage_bit >> 3;
94            std::byte damage_val{(uint8_t)(1U << (damage_bit & 7))};
95            if (damage_pos >= cipher.size()) {
96                aad[damage_pos - cipher.size()] ^= damage_val;
97            } else {
98                cipher[damage_pos] ^= damage_val;
99            }
100        }
101
102        if (use_splits && length > 0) {
103            size_t split_index = provider.ConsumeIntegralInRange<size_t>(1, length);
104            ok = aead.Decrypt(cipher, aad, nonce, std::span{decrypted_contents}.first(split_index), std::span{decrypted_contents}.subspan(split_index));
105        } else {
106            ok = aead.Decrypt(cipher, aad, nonce, decrypted_contents);
107        }
108
109        // Decryption *must* fail if the packet was damaged, and succeed if it wasn't.
110        assert(!ok == damage);
111        if (!ok) break;
112        assert(decrypted_contents == plain);
113    }
114}
115
116FUZZ_TARGET(crypto_fschacha20poly1305)
117{
118    FuzzedDataProvider provider{buffer.data(), buffer.size()};
119
120    uint32_t rekey_interval = provider.ConsumeIntegralInRange<size_t>(32, 512);
121    auto key = provider.ConsumeBytes<std::byte>(32);
122    key.resize(32);
123    FSChaCha20Poly1305 enc_aead(key, rekey_interval);
124    FSChaCha20Poly1305 dec_aead(key, rekey_interval);
125
126    // Initialize RNG deterministically, to generate contents and AAD. We assume that there are no
127    // (potentially buggy) edge cases triggered by specific values of contents/AAD, so we can avoid
128    // reading the actual data for those from the fuzzer input (which would need large amounts of
129    // data).
130    InsecureRandomContext rng(provider.ConsumeIntegral<uint64_t>());
131
132    LIMITED_WHILE (provider.ConsumeBool(), 100) {
133        // Mode:
134        // - Bit 0: whether to use single-plain Encrypt/Decrypt; otherwise use a split at prefix.
135        // - Bit 2: whether this ciphertext will be corrupted (making it the last sent one)
136        // - Bit 3-4: controls the maximum aad length (max 511 bytes)
137        // - Bit 5-7: controls the maximum content length (max 16383 bytes, for performance reasons)
138        unsigned mode = provider.ConsumeIntegral<uint8_t>();
139        bool use_splits = mode & 1;
140        bool damage = mode & 4;
141        unsigned aad_length_bits = 3 * ((mode >> 3) & 3);
142        unsigned aad_length = provider.ConsumeIntegralInRange<unsigned>(0, (1 << aad_length_bits) - 1);
143        unsigned length_bits = 2 * ((mode >> 5) & 7);
144        unsigned length = provider.ConsumeIntegralInRange<unsigned>(0, (1 << length_bits) - 1);
145        // Generate aad and content.
146        auto aad = rng.randbytes<std::byte>(aad_length);
147        auto plain = rng.randbytes<std::byte>(length);
148        std::vector<std::byte> cipher(length + FSChaCha20Poly1305::EXPANSION);
149
150        crypt_till_rekey(enc_aead, rekey_interval, true);
151        if (use_splits && length > 0) {
152            size_t split_index = provider.ConsumeIntegralInRange<size_t>(1, length);
153            enc_aead.Encrypt(std::span{plain}.first(split_index), std::span{plain}.subspan(split_index), aad, cipher);
154        } else {
155            enc_aead.Encrypt(plain, aad, cipher);
156        }
157
158        std::vector<std::byte> decrypted_contents(length);
159        bool ok{false};
160
161        // damage the key
162        unsigned key_position = provider.ConsumeIntegralInRange<unsigned>(0, 31);
163        std::byte damage_val{(uint8_t)(1U << (key_position & 7))};
164        std::vector<std::byte> bad_key = key;
165        bad_key[key_position] ^= damage_val;
166
167        FSChaCha20Poly1305 bad_fs_aead(bad_key, rekey_interval);
168        crypt_till_rekey(bad_fs_aead, rekey_interval, false);
169        ok = bad_fs_aead.Decrypt(cipher, aad, decrypted_contents);
170        assert(!ok);
171
172        // Optionally damage 1 bit in either the cipher (corresponding to a change in transit)
173        // or the aad (to make sure that decryption will fail if the AAD mismatches).
174        if (damage) {
175            unsigned damage_bit = provider.ConsumeIntegralInRange<unsigned>(0, (cipher.size() + aad.size()) * 8U - 1U);
176            unsigned damage_pos = damage_bit >> 3;
177            std::byte damage_val{(uint8_t)(1U << (damage_bit & 7))};
178            if (damage_pos >= cipher.size()) {
179                aad[damage_pos - cipher.size()] ^= damage_val;
180            } else {
181                cipher[damage_pos] ^= damage_val;
182            }
183        }
184
185        crypt_till_rekey(dec_aead, rekey_interval, false);
186        if (use_splits && length > 0) {
187            size_t split_index = provider.ConsumeIntegralInRange<size_t>(1, length);
188            ok = dec_aead.Decrypt(cipher, aad, std::span{decrypted_contents}.first(split_index), std::span{decrypted_contents}.subspan(split_index));
189        } else {
190            ok = dec_aead.Decrypt(cipher, aad, decrypted_contents);
191        }
192
193        // Decryption *must* fail if the packet was damaged, and succeed if it wasn't.
194        assert(!ok == damage);
195        if (!ok) break;
196        assert(decrypted_contents == plain);
197    }
198}
199

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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