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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server440 file guides

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1// Copyright (c) 2023-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 <bip324.h>
6#include <chainparams.h>
7#include <random.h>
8#include <span.h>
9#include <test/fuzz/FuzzedDataProvider.h>
10#include <test/fuzz/fuzz.h>
11#include <test/fuzz/util.h>
12
13#include <algorithm>
14#include <cstdint>
15#include <vector>
16
17namespace {
18
19void Initialize()
20{
21    static ECC_Context ecc_context{};
22    SelectParams(ChainType::MAIN);
23}
24
25}  // namespace
26
27FUZZ_TARGET(bip324_cipher_roundtrip, .init=Initialize)
28{
29    // Test that BIP324Cipher's encryption and decryption agree.
30
31    // Load keys from fuzzer.
32    FuzzedDataProvider provider(buffer.data(), buffer.size());
33    // Initiator key
34    CKey init_key = ConsumePrivateKey(provider, /*compressed=*/true);
35    if (!init_key.IsValid()) return;
36    // Initiator entropy
37    auto init_ent = provider.ConsumeBytes<std::byte>(32);
38    init_ent.resize(32);
39    // Responder key
40    CKey resp_key = ConsumePrivateKey(provider, /*compressed=*/true);
41    if (!resp_key.IsValid()) return;
42    // Responder entropy
43    auto resp_ent = provider.ConsumeBytes<std::byte>(32);
44    resp_ent.resize(32);
45
46    // Initialize ciphers by exchanging public keys.
47    BIP324Cipher initiator(init_key, init_ent);
48    assert(!initiator);
49    BIP324Cipher responder(resp_key, resp_ent);
50    assert(!responder);
51    initiator.Initialize(responder.GetOurPubKey(), true);
52    assert(initiator);
53    responder.Initialize(initiator.GetOurPubKey(), false);
54    assert(responder);
55
56    // Initialize RNG deterministically, to generate contents and AAD. We assume that there are no
57    // (potentially buggy) edge cases triggered by specific values of contents/AAD, so we can avoid
58    // reading the actual data for those from the fuzzer input (which would need large amounts of
59    // data).
60    InsecureRandomContext rng(provider.ConsumeIntegral<uint64_t>());
61
62    // Compare session IDs and garbage terminators.
63    assert(std::ranges::equal(initiator.GetSessionID(), responder.GetSessionID()));
64    assert(std::ranges::equal(initiator.GetSendGarbageTerminator(), responder.GetReceiveGarbageTerminator()));
65    assert(std::ranges::equal(initiator.GetReceiveGarbageTerminator(), responder.GetSendGarbageTerminator()));
66
67    LIMITED_WHILE (provider.remaining_bytes(), 1000) {
68        // Mode:
69        // - Bit 0: whether the ignore bit is set in message
70        // - Bit 1: whether the responder (0) or initiator (1) sends
71        // - Bit 2: whether this ciphertext will be corrupted (making it the last sent one)
72        // - Bit 3-4: controls the maximum aad length (max 4095 bytes)
73        // - Bit 5-7: controls the maximum content length (max 16383 bytes, for performance reasons)
74        unsigned mode = provider.ConsumeIntegral<uint8_t>();
75        bool ignore = mode & 1;
76        bool from_init = mode & 2;
77        bool damage = mode & 4;
78        unsigned aad_length_bits = 4 * ((mode >> 3) & 3);
79        unsigned aad_length = provider.ConsumeIntegralInRange<unsigned>(0, (1 << aad_length_bits) - 1);
80        unsigned length_bits = 2 * ((mode >> 5) & 7);
81        unsigned length = provider.ConsumeIntegralInRange<unsigned>(0, (1 << length_bits) - 1);
82        // Generate aad and content.
83        auto aad = rng.randbytes<std::byte>(aad_length);
84        auto contents = rng.randbytes<std::byte>(length);
85
86        // Pick sides.
87        auto& sender{from_init ? initiator : responder};
88        auto& receiver{from_init ? responder : initiator};
89
90        // Encrypt
91        std::vector<std::byte> ciphertext(length + initiator.EXPANSION);
92        sender.Encrypt(contents, aad, ignore, ciphertext);
93
94        // Optionally damage 1 bit in either the ciphertext (corresponding to a change in transit)
95        // or the aad (to make sure that decryption will fail if the AAD mismatches).
96        if (damage) {
97            unsigned damage_bit = provider.ConsumeIntegralInRange<unsigned>(0,
98                (ciphertext.size() + aad.size()) * 8U - 1U);
99            unsigned damage_pos = damage_bit >> 3;
100            std::byte damage_val{(uint8_t)(1U << (damage_bit & 7))};
101            if (damage_pos >= ciphertext.size()) {
102                aad[damage_pos - ciphertext.size()] ^= damage_val;
103            } else {
104                ciphertext[damage_pos] ^= damage_val;
105            }
106        }
107
108        // Decrypt length
109        uint32_t dec_length = receiver.DecryptLength(std::span{ciphertext}.first(initiator.LENGTH_LEN));
110        if (!damage) {
111            assert(dec_length == length);
112        } else {
113            // For performance reasons, don't try to decode if length got increased too much.
114            if (dec_length > 16384 + length) break;
115            // Otherwise, just append zeros if dec_length > length.
116            ciphertext.resize(dec_length + initiator.EXPANSION);
117        }
118
119        // Decrypt
120        std::vector<std::byte> decrypt(dec_length);
121        bool dec_ignore{false};
122        bool ok = receiver.Decrypt(std::span{ciphertext}.subspan(initiator.LENGTH_LEN), aad, dec_ignore, decrypt);
123        // Decryption *must* fail if the packet was damaged, and succeed if it wasn't.
124        assert(!ok == damage);
125        if (!ok) break;
126        assert(ignore == dec_ignore);
127        assert(decrypt == contents);
128    }
129}
130

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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