1 // Copyright (c) 2020 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 
9 #include <cstdint>
10 #include <string>
11 #include <vector>
12 
13 #if defined(__has_builtin)
14 #if __has_builtin(__builtin_mul_overflow)
15 #define HAVE_BUILTIN_MUL_OVERFLOW
16 #endif
17 #elif defined(__GNUC__) && (__GNUC__ >= 5)
18 #define HAVE_BUILTIN_MUL_OVERFLOW
19 #endif
20 
21 namespace {
22 template <typename T>
TestMultiplicationOverflow(FuzzedDataProvider & fuzzed_data_provider)23 void TestMultiplicationOverflow(FuzzedDataProvider& fuzzed_data_provider)
24 {
25     const T i = fuzzed_data_provider.ConsumeIntegral<T>();
26     const T j = fuzzed_data_provider.ConsumeIntegral<T>();
27     const bool is_multiplication_overflow_custom = MultiplicationOverflow(i, j);
28 #if defined(HAVE_BUILTIN_MUL_OVERFLOW)
29     T result_builtin;
30     const bool is_multiplication_overflow_builtin = __builtin_mul_overflow(i, j, &result_builtin);
31     assert(is_multiplication_overflow_custom == is_multiplication_overflow_builtin);
32     if (!is_multiplication_overflow_custom) {
33         assert(i * j == result_builtin);
34     }
35 #else
36     if (!is_multiplication_overflow_custom) {
37         (void)(i * j);
38     }
39 #endif
40 }
41 } // namespace
42 
test_one_input(const std::vector<uint8_t> & buffer)43 void test_one_input(const std::vector<uint8_t>& buffer)
44 {
45     FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
46     TestMultiplicationOverflow<int64_t>(fuzzed_data_provider);
47     TestMultiplicationOverflow<uint64_t>(fuzzed_data_provider);
48     TestMultiplicationOverflow<int32_t>(fuzzed_data_provider);
49     TestMultiplicationOverflow<uint32_t>(fuzzed_data_provider);
50     TestMultiplicationOverflow<int16_t>(fuzzed_data_provider);
51     TestMultiplicationOverflow<uint16_t>(fuzzed_data_provider);
52     TestMultiplicationOverflow<char>(fuzzed_data_provider);
53     TestMultiplicationOverflow<unsigned char>(fuzzed_data_provider);
54     TestMultiplicationOverflow<signed char>(fuzzed_data_provider);
55 }
56