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"
18 #ifndef OPENSSL_NO_ENGINE
19 /* non-NULL if default_RAND_meth is ENGINE-provided */
20 static ENGINE *funct_ref = NULL;
21 static CRYPTO_RWLOCK *rand_engine_lock = NULL;
23 static const RAND_METHOD *default_RAND_meth = NULL;
24 static CRYPTO_RWLOCK *rand_meth_lock = NULL;
25 static CRYPTO_ONCE rand_lock_init = CRYPTO_ONCE_STATIC_INIT;
27 DEFINE_RUN_ONCE_STATIC(do_rand_lock_init)
30 #ifndef OPENSSL_NO_ENGINE
31 rand_engine_lock = CRYPTO_THREAD_lock_new();
32 ret &= rand_engine_lock != NULL;
34 rand_meth_lock = CRYPTO_THREAD_lock_new();
35 ret &= rand_meth_lock != NULL;
39 int RAND_set_rand_method(const RAND_METHOD *meth)
41 if (!RUN_ONCE(&rand_lock_init, do_rand_lock_init))
44 CRYPTO_THREAD_write_lock(rand_meth_lock);
45 #ifndef OPENSSL_NO_ENGINE
46 ENGINE_finish(funct_ref);
49 default_RAND_meth = meth;
50 CRYPTO_THREAD_unlock(rand_meth_lock);
54 const RAND_METHOD *RAND_get_rand_method(void)
56 const RAND_METHOD *tmp_meth = NULL;
58 if (!RUN_ONCE(&rand_lock_init, do_rand_lock_init))
61 CRYPTO_THREAD_write_lock(rand_meth_lock);
62 if (!default_RAND_meth) {
63 #ifndef OPENSSL_NO_ENGINE
64 ENGINE *e = ENGINE_get_default_RAND();
66 default_RAND_meth = ENGINE_get_RAND(e);
67 if (default_RAND_meth == NULL) {
76 default_RAND_meth = RAND_OpenSSL();
78 tmp_meth = default_RAND_meth;
79 CRYPTO_THREAD_unlock(rand_meth_lock);
83 #ifndef OPENSSL_NO_ENGINE
84 int RAND_set_rand_engine(ENGINE *engine)
86 const RAND_METHOD *tmp_meth = NULL;
88 if (!RUN_ONCE(&rand_lock_init, do_rand_lock_init))
92 if (!ENGINE_init(engine))
94 tmp_meth = ENGINE_get_RAND(engine);
95 if (tmp_meth == NULL) {
96 ENGINE_finish(engine);
100 CRYPTO_THREAD_write_lock(rand_engine_lock);
101 /* This function releases any prior ENGINE so call it first */
102 RAND_set_rand_method(tmp_meth);
104 CRYPTO_THREAD_unlock(rand_engine_lock);
109 void rand_cleanup_int(void)
111 const RAND_METHOD *meth = default_RAND_meth;
112 if (meth && meth->cleanup)
114 RAND_set_rand_method(NULL);
115 CRYPTO_THREAD_lock_free(rand_meth_lock);
116 CRYPTO_THREAD_lock_free(rand_engine_lock);
119 void RAND_seed(const void *buf, int num)
121 const RAND_METHOD *meth = RAND_get_rand_method();
122 if (meth && meth->seed)
123 meth->seed(buf, num);
126 void RAND_add(const void *buf, int num, double entropy)
128 const RAND_METHOD *meth = RAND_get_rand_method();
129 if (meth && meth->add)
130 meth->add(buf, num, entropy);
133 int RAND_bytes(unsigned char *buf, int num)
135 const RAND_METHOD *meth = RAND_get_rand_method();
136 if (meth && meth->bytes)
137 return meth->bytes(buf, num);
141 #if OPENSSL_API_COMPAT < 0x10100000L
142 int RAND_pseudo_bytes(unsigned char *buf, int num)
144 const RAND_METHOD *meth = RAND_get_rand_method();
145 if (meth && meth->pseudorand)
146 return meth->pseudorand(buf, num);
151 int RAND_status(void)
153 const RAND_METHOD *meth = RAND_get_rand_method();
154 if (meth && meth->status)
155 return meth->status();