Inside Bitcoin

1// Copyright (c) 2022-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/FuzzedDataProvider.h>
6#include <test/fuzz/fuzz.h>
7#include <test/fuzz/util.h>
8#include <test/util/setup_common.h>
9#include <wallet/crypter.h>
10
11namespace wallet {
12namespace {
13
14void initialize_crypter()
15{
16    static const auto testing_setup = MakeNoLogFileContext<const TestingSetup>();
17}
18
19FUZZ_TARGET(crypter, .init = initialize_crypter)
20{
21    SeedRandomStateForTest(SeedRand::ZEROS);
22    FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
23    bool good_data{true};
24
25    CCrypter crypt;
26    // These values are regularly updated within `CallOneOf`
27    std::vector<unsigned char> cipher_text_ed;
28    CKeyingMaterial plain_text_ed;
29    const std::vector<unsigned char> random_key = ConsumeFixedLengthByteVector(fuzzed_data_provider, WALLET_CRYPTO_KEY_SIZE);
30
31    if (fuzzed_data_provider.ConsumeBool()) {
32        const std::string random_string = fuzzed_data_provider.ConsumeRandomLengthString(100);
33        SecureString secure_string(random_string.begin(), random_string.end());
34
35        const unsigned int derivation_method = fuzzed_data_provider.ConsumeBool() ? 0 : fuzzed_data_provider.ConsumeIntegral<unsigned int>();
36
37        // Limiting the value of rounds since it is otherwise uselessly expensive and causes a timeout when fuzzing.
38        (void)crypt.SetKeyFromPassphrase(/*key_data=*/secure_string,
39                                         /*salt=*/ConsumeFixedLengthByteVector(fuzzed_data_provider, WALLET_CRYPTO_SALT_SIZE),
40                                         /*rounds=*/fuzzed_data_provider.ConsumeIntegralInRange<unsigned int>(0, CMasterKey::DEFAULT_DERIVE_ITERATIONS),
41                                         /*derivation_method=*/derivation_method);
42    }
43
44    CKey random_ckey;
45    random_ckey.Set(random_key.begin(), random_key.end(), /*fCompressedIn=*/fuzzed_data_provider.ConsumeBool());
46    if (!random_ckey.IsValid()) return;
47    CPubKey pubkey{random_ckey.GetPubKey()};
48
49    LIMITED_WHILE (good_data && fuzzed_data_provider.ConsumeBool(), 100) {
50        CallOneOf(
51            fuzzed_data_provider,
52            [&] {
53                const std::vector<unsigned char> random_vector = ConsumeFixedLengthByteVector(fuzzed_data_provider, WALLET_CRYPTO_KEY_SIZE);
54                plain_text_ed = CKeyingMaterial(random_vector.begin(), random_vector.end());
55            },
56            [&] {
57                cipher_text_ed = ConsumeRandomLengthByteVector(fuzzed_data_provider, 64);
58            },
59            [&] {
60                (void)crypt.Encrypt(plain_text_ed, cipher_text_ed);
61            },
62            [&] {
63                (void)crypt.Decrypt(cipher_text_ed, plain_text_ed);
64            },
65            [&] {
66                const CKeyingMaterial master_key(random_key.begin(), random_key.end());
67                (void)EncryptSecret(master_key, plain_text_ed, pubkey.GetHash(), cipher_text_ed);
68            },
69            [&] {
70                std::optional<CPubKey> random_pub_key{ConsumeDeserializable<CPubKey>(fuzzed_data_provider)};
71                if (!random_pub_key) {
72                    good_data = false;
73                    return;
74                }
75                pubkey = *random_pub_key;
76            },
77            [&] {
78                const CKeyingMaterial master_key(random_key.begin(), random_key.end());
79                CKey key;
80                (void)DecryptKey(master_key, cipher_text_ed, pubkey, key);
81            });
82    }
83}
84} // namespace
85} // namespace wallet
86