| /* This Source Code Form is subject to the terms of the Mozilla Public |
| * License, v. 2.0. If a copy of the MPL was not distributed with this |
| * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
| |
| /* |
| * This target fuzzes NSS mpi against openssl bignum. |
| * It therefore requires openssl to be installed. |
| */ |
| |
| #include "mpi_helper.h" |
| |
| extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) { |
| // We require at least size 3 to get two integers from Data. |
| if (size < 3) { |
| return 0; |
| } |
| INIT_FOUR_NUMBERS |
| |
| auto modulus = get_modulus(data, size, ctx); |
| // Compare with OpenSSL exp mod |
| m1 = &std::get<1>(modulus); |
| // The exponent b (B) can get really big. Make it smaller if necessary. |
| if (MP_USED(&b) > 100) { |
| size_t shift = (MP_USED(&b) - 100) * MP_DIGIT_BIT; |
| mp_div_2d(&b, shift, &b, nullptr); |
| BN_rshift(B, B, shift); |
| } |
| check_equal(A, &a, max_size); |
| check_equal(B, &b, max_size); |
| check_equal(std::get<0>(modulus), m1, 3 * max_size); |
| assert(mp_exptmod(&a, &b, m1, &c) == MP_OKAY); |
| (void)BN_mod_exp(C, A, B, std::get<0>(modulus), ctx); |
| check_equal(C, &c, 2 * max_size); |
| |
| CLEANUP_AND_RETURN |
| } |