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 #ifndef OPENSSL_HEADER_RAND_H 16 #define OPENSSL_HEADER_RAND_H 17 18 #include <openssl/base.h> 19 20 #if defined(__cplusplus) 21 extern "C" { 22 #endif 23 24 25 // Random number generation. 26 27 28 // RAND_bytes writes |len| bytes of random data to |buf| and returns one. 29 OPENSSL_EXPORT int RAND_bytes(uint8_t *buf, size_t len); 30 31 // RAND_cleanup frees any resources used by the RNG. This is not safe if other 32 // threads might still be calling |RAND_bytes|. 33 OPENSSL_EXPORT void RAND_cleanup(void); 34 35 36 // Obscure functions. 37 38 #if !defined(OPENSSL_WINDOWS) 39 // RAND_enable_fork_unsafe_buffering enables efficient buffered reading of 40 // /dev/urandom. It adds an overhead of a few KB of memory per thread. It must 41 // be called before the first call to |RAND_bytes|. 42 // 43 // |fd| must be -1. We no longer support setting the file descriptor with this 44 // function. 45 // 46 // It has an unusual name because the buffer is unsafe across calls to |fork|. 47 // Hence, this function should never be called by libraries. 48 OPENSSL_EXPORT void RAND_enable_fork_unsafe_buffering(int fd); 49 #endif 50 51 #if defined(BORINGSSL_UNSAFE_DETERMINISTIC_MODE) 52 // RAND_reset_for_fuzzing resets the fuzzer-only deterministic RNG. This 53 // function is only defined in the fuzzer-only build configuration. 54 OPENSSL_EXPORT void RAND_reset_for_fuzzing(void); 55 #endif 56 57 58 // Deprecated functions 59 60 // RAND_pseudo_bytes is a wrapper around |RAND_bytes|. 61 OPENSSL_EXPORT int RAND_pseudo_bytes(uint8_t *buf, size_t len); 62 63 // RAND_seed reads a single byte of random data to ensure that any file 64 // descriptors etc are opened. 65 OPENSSL_EXPORT void RAND_seed(const void *buf, int num); 66 67 // RAND_load_file returns a nonnegative number. 68 OPENSSL_EXPORT int RAND_load_file(const char *path, long num); 69 70 // RAND_file_name returns NULL. 71 OPENSSL_EXPORT const char *RAND_file_name(char *buf, size_t num); 72 73 // RAND_add does nothing. 74 OPENSSL_EXPORT void RAND_add(const void *buf, int num, double entropy); 75 76 // RAND_egd returns 255. 77 OPENSSL_EXPORT int RAND_egd(const char *); 78 79 // RAND_poll returns one. 80 OPENSSL_EXPORT int RAND_poll(void); 81 82 // RAND_status returns one. 83 OPENSSL_EXPORT int RAND_status(void); 84 85 // rand_meth_st is typedefed to |RAND_METHOD| in base.h. It isn't used; it 86 // exists only to be the return type of |RAND_SSLeay|. It's 87 // external so that variables of this type can be initialized. 88 struct rand_meth_st { 89 void (*seed) (const void *buf, int num); 90 int (*bytes) (uint8_t *buf, size_t num); 91 void (*cleanup) (void); 92 void (*add) (const void *buf, int num, double entropy); 93 int (*pseudorand) (uint8_t *buf, size_t num); 94 int (*status) (void); 95 }; 96 97 // RAND_SSLeay returns a pointer to a dummy |RAND_METHOD|. 98 OPENSSL_EXPORT RAND_METHOD *RAND_SSLeay(void); 99 100 // RAND_OpenSSL returns a pointer to a dummy |RAND_METHOD|. 101 OPENSSL_EXPORT RAND_METHOD *RAND_OpenSSL(void); 102 103 // RAND_get_rand_method returns |RAND_SSLeay()|. 104 OPENSSL_EXPORT const RAND_METHOD *RAND_get_rand_method(void); 105 106 // RAND_set_rand_method does nothing. 107 OPENSSL_EXPORT void RAND_set_rand_method(const RAND_METHOD *); 108 109 110 #if defined(__cplusplus) 111 } // extern C 112 #endif 113 114 #endif // OPENSSL_HEADER_RAND_H 115