2 * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
12 #include "internal/cryptlib.h"
13 #include <openssl/opensslconf.h>
14 #include "internal/rand.h"
15 #include <openssl/engine.h>
16 #include "internal/thread_once.h"
19 #ifndef OPENSSL_NO_ENGINE
20 /* non-NULL if default_RAND_meth is ENGINE-provided */
21 static ENGINE *funct_ref;
22 static CRYPTO_RWLOCK *rand_engine_lock;
24 static CRYPTO_RWLOCK *rand_meth_lock;
25 static const RAND_METHOD *default_RAND_meth;
26 static CRYPTO_ONCE rand_init = CRYPTO_ONCE_STATIC_INIT;
29 DEFINE_RUN_ONCE_STATIC(do_rand_init)
32 #ifndef OPENSSL_NO_ENGINE
33 rand_engine_lock = CRYPTO_THREAD_lock_new();
34 ret &= rand_engine_lock != NULL;
36 rand_meth_lock = CRYPTO_THREAD_lock_new();
37 ret &= rand_meth_lock != NULL;
41 void rand_cleanup_int(void)
43 const RAND_METHOD *meth = default_RAND_meth;
45 if (meth != NULL && meth->cleanup != NULL)
47 RAND_set_rand_method(NULL);
48 #ifndef OPENSSL_NO_ENGINE
49 CRYPTO_THREAD_lock_free(rand_engine_lock);
51 CRYPTO_THREAD_lock_free(rand_meth_lock);
54 int RAND_set_rand_method(const RAND_METHOD *meth)
56 if (!RUN_ONCE(&rand_init, do_rand_init))
59 CRYPTO_THREAD_write_lock(rand_meth_lock);
60 #ifndef OPENSSL_NO_ENGINE
61 ENGINE_finish(funct_ref);
64 default_RAND_meth = meth;
65 CRYPTO_THREAD_unlock(rand_meth_lock);
69 const RAND_METHOD *RAND_get_rand_method(void)
71 const RAND_METHOD *tmp_meth = NULL;
73 if (!RUN_ONCE(&rand_init, do_rand_init))
76 CRYPTO_THREAD_write_lock(rand_meth_lock);
77 if (default_RAND_meth == NULL) {
78 #ifndef OPENSSL_NO_ENGINE
81 /* If we have an engine that can do RAND, use it. */
82 if ((e = ENGINE_get_default_RAND()) != NULL
83 && (tmp_meth = ENGINE_get_RAND(e)) != NULL) {
85 default_RAND_meth = tmp_meth;
88 default_RAND_meth = &openssl_rand_meth;
91 default_RAND_meth = &openssl_rand_meth;
94 tmp_meth = default_RAND_meth;
95 CRYPTO_THREAD_unlock(rand_meth_lock);
99 #ifndef OPENSSL_NO_ENGINE
100 int RAND_set_rand_engine(ENGINE *engine)
102 const RAND_METHOD *tmp_meth = NULL;
104 if (!RUN_ONCE(&rand_init, do_rand_init))
107 if (engine != NULL) {
108 if (!ENGINE_init(engine))
110 tmp_meth = ENGINE_get_RAND(engine);
111 if (tmp_meth == NULL) {
112 ENGINE_finish(engine);
116 CRYPTO_THREAD_write_lock(rand_engine_lock);
117 /* This function releases any prior ENGINE so call it first */
118 RAND_set_rand_method(tmp_meth);
120 CRYPTO_THREAD_unlock(rand_engine_lock);
125 void RAND_seed(const void *buf, int num)
127 const RAND_METHOD *meth = RAND_get_rand_method();
129 if (meth->seed != NULL)
130 meth->seed(buf, num);
133 void RAND_add(const void *buf, int num, double randomness)
135 const RAND_METHOD *meth = RAND_get_rand_method();
137 if (meth->add != NULL)
138 meth->add(buf, num, randomness);
141 int RAND_bytes(unsigned char *buf, int num)
143 const RAND_METHOD *meth = RAND_get_rand_method();
145 if (meth->bytes != NULL)
146 return meth->bytes(buf, num);
147 RANDerr(RAND_F_RAND_BYTES, RAND_R_FUNC_NOT_IMPLEMENTED);
151 #if OPENSSL_API_COMPAT < 0x10100000L
152 int RAND_pseudo_bytes(unsigned char *buf, int num)
154 const RAND_METHOD *meth = RAND_get_rand_method();
156 if (meth->pseudorand != NULL)
157 return meth->pseudorand(buf, num);
162 int RAND_status(void)
164 const RAND_METHOD *meth = RAND_get_rand_method();
166 if (meth->status != NULL)
167 return meth->status();