| /* Copyright (c) 2016, Google Inc. |
| * |
| * Permission to use, copy, modify, and/or distribute this software for any |
| * purpose with or without fee is hereby granted, provided that the above |
| * copyright notice and this permission notice appear in all copies. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES |
| * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
| * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY |
| * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION |
| * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN |
| * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ |
| |
| #include <openssl/rand.h> |
| |
| #if defined(BORINGSSL_UNSAFE_DETERMINISTIC_MODE) |
| |
| #include <string.h> |
| |
| #include <openssl/chacha.h> |
| |
| #include "internal.h" |
| |
| |
| /* g_num_calls is the number of calls to |CRYPTO_sysrand| that have occured. |
| * |
| * TODO(davidben): This is intentionally not thread-safe. If the fuzzer mode is |
| * ever used in a multi-threaded program, replace this with a thread-local. (A |
| * mutex would not be deterministic.) */ |
| static uint64_t g_num_calls = 0; |
| |
| void RAND_reset_for_fuzzing(void) { g_num_calls = 0; } |
| |
| void CRYPTO_sysrand(uint8_t *out, size_t requested) { |
| static const uint8_t kZeroKey[32]; |
| |
| uint8_t nonce[12]; |
| OPENSSL_memset(nonce, 0, sizeof(nonce)); |
| OPENSSL_memcpy(nonce, &g_num_calls, sizeof(g_num_calls)); |
| |
| OPENSSL_memset(out, 0, requested); |
| CRYPTO_chacha_20(out, out, requested, kZeroKey, nonce, 0); |
| g_num_calls++; |
| } |
| |
| #endif /* BORINGSSL_UNSAFE_DETERMINISTIC_MODE */ |