1 /* Copyright (c) 2014, Google Inc. 2 * 3 * Permission to use, copy, modify, and/or distribute this software for any 4 * purpose with or without fee is hereby granted, provided that the above 5 * copyright notice and this permission notice appear in all copies. 6 * 7 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 8 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 9 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY 10 * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 11 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION 12 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN 13 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ 14 15 #include <openssl/rand.h> 16 17 #include <openssl/thread.h> 18 19 20 #if defined(OPENSSL_WINDOWS) 21 22 #include <stdlib.h> 23 #include <Windows.h> 24 #include <Wincrypt.h> 25 26 static char global_provider_init; 27 static HCRYPTPROV global_provider; 28 29 void RAND_cleanup(void) { 30 CRYPTO_w_lock(CRYPTO_LOCK_RAND); 31 CryptReleaseContext(global_provider, 0); 32 global_provider_init = 0; 33 CRYPTO_w_unlock(CRYPTO_LOCK_RAND); 34 } 35 36 int RAND_bytes(uint8_t *out, size_t requested) { 37 HCRYPTPROV provider = 0; 38 int ok; 39 40 CRYPTO_r_lock(CRYPTO_LOCK_RAND); 41 if (!global_provider_init) { 42 CRYPTO_r_unlock(CRYPTO_LOCK_RAND); 43 CRYPTO_w_lock(CRYPTO_LOCK_RAND); 44 if (!global_provider_init) { 45 if (CryptAcquireContext(&global_provider, NULL, NULL, PROV_RSA_FULL, 46 CRYPT_VERIFYCONTEXT | CRYPT_SILENT)) { 47 global_provider_init = 1; 48 } 49 } 50 CRYPTO_w_unlock(CRYPTO_LOCK_RAND); 51 CRYPTO_r_lock(CRYPTO_LOCK_RAND); 52 } 53 54 ok = global_provider_init; 55 provider = global_provider; 56 CRYPTO_r_unlock(CRYPTO_LOCK_RAND); 57 58 if (!ok) { 59 abort(); 60 return ok; 61 } 62 63 if (TRUE != CryptGenRandom(provider, requested, out)) { 64 abort(); 65 return 0; 66 } 67 68 return 1; 69 } 70 71 #endif /* OPENSSL_WINDOWS */ 72