1 /* crypto/rand/rand_lib.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3 * All rights reserved.
4 *
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
8 *
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 *
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
22 *
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
25 * are met:
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 *
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51 * SUCH DAMAGE.
52 *
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
57 */
58
59 #include <stdio.h>
60 #include <time.h>
61 #include "cryptlib.h"
62 #include <openssl/rand.h>
63
64 #ifndef OPENSSL_NO_ENGINE
65 #include <openssl/engine.h>
66 #endif
67
68 #ifdef OPENSSL_FIPS
69 #include <openssl/fips.h>
70 #include <openssl/fips_rand.h>
71 #include "rand_lcl.h"
72 #endif
73
74 #ifndef OPENSSL_NO_ENGINE
75 /* non-NULL if default_RAND_meth is ENGINE-provided */
76 static ENGINE *funct_ref =NULL;
77 #endif
78 static const RAND_METHOD *default_RAND_meth = NULL;
79
80 int RAND_set_rand_method(const RAND_METHOD *meth)
81 {
82 #ifndef OPENSSL_NO_ENGINE
83 if(funct_ref)
84 {
85 ENGINE_finish(funct_ref);
86 funct_ref = NULL;
87 }
88 #endif
89 default_RAND_meth = meth;
90 return 1;
91 }
92
93 const RAND_METHOD *RAND_get_rand_method(void)
94 {
95 if (!default_RAND_meth)
96 {
97 #ifndef OPENSSL_NO_ENGINE
98 ENGINE *e = ENGINE_get_default_RAND();
99 if(e)
100 {
101 default_RAND_meth = ENGINE_get_RAND(e);
102 if(!default_RAND_meth)
103 {
104 ENGINE_finish(e);
105 e = NULL;
106 }
107 }
108 if(e)
109 funct_ref = e;
110 else
111 #endif
112 default_RAND_meth = RAND_SSLeay();
113 }
114 return default_RAND_meth;
115 }
116
117 #ifndef OPENSSL_NO_ENGINE
118 int RAND_set_rand_engine(ENGINE *engine)
119 {
120 const RAND_METHOD *tmp_meth = NULL;
121 if(engine)
122 {
123 if(!ENGINE_init(engine))
124 return 0;
125 tmp_meth = ENGINE_get_RAND(engine);
126 if(!tmp_meth)
127 {
128 ENGINE_finish(engine);
129 return 0;
130 }
131 }
132 /* This function releases any prior ENGINE so call it first */
133 RAND_set_rand_method(tmp_meth);
134 funct_ref = engine;
135 return 1;
136 }
137 #endif
138
139 void RAND_cleanup(void)
140 {
141 const RAND_METHOD *meth = RAND_get_rand_method();
142 if (meth && meth->cleanup)
143 meth->cleanup();
144 RAND_set_rand_method(NULL);
145 }
146
147 void RAND_seed(const void *buf, int num)
148 {
149 const RAND_METHOD *meth = RAND_get_rand_method();
150 if (meth && meth->seed)
151 meth->seed(buf,num);
152 }
153
154 void RAND_add(const void *buf, int num, double entropy)
155 {
156 const RAND_METHOD *meth = RAND_get_rand_method();
157 if (meth && meth->add)
158 meth->add(buf,num,entropy);
159 }
160
161 int RAND_bytes(unsigned char *buf, int num)
162 {
163 const RAND_METHOD *meth = RAND_get_rand_method();
164 if (meth && meth->bytes)
165 return meth->bytes(buf,num);
166 return(-1);
167 }
168
169 int RAND_pseudo_bytes(unsigned char *buf, int num)
170 {
171 const RAND_METHOD *meth = RAND_get_rand_method();
172 if (meth && meth->pseudorand)
173 return meth->pseudorand(buf,num);
174 return(-1);
175 }
176
177 int RAND_status(void)
178 {
179 const RAND_METHOD *meth = RAND_get_rand_method();
180 if (meth && meth->status)
181 return meth->status();
182 return 0;
183 }
184
185 #ifdef OPENSSL_FIPS
186
187 /* FIPS DRBG initialisation code. This sets up the DRBG for use by the
188 * rest of OpenSSL.
189 */
190
191 /* Entropy gatherer: use standard OpenSSL PRNG to seed (this will gather
192 * entropy internally through RAND_poll().
193 */
194
195 static size_t drbg_get_entropy(DRBG_CTX *ctx, unsigned char **pout,
196 int entropy, size_t min_len, size_t max_len)
197 {
198 /* Round up request to multiple of block size */
199 min_len = ((min_len + 19) / 20) * 20;
200 *pout = OPENSSL_malloc(min_len);
201 if (!*pout)
202 return 0;
203 if (ssleay_rand_bytes(*pout, min_len, 0, 0) <= 0)
204 {
205 OPENSSL_free(*pout);
206 *pout = NULL;
207 return 0;
208 }
209 return min_len;
210 }
211
212 static void drbg_free_entropy(DRBG_CTX *ctx, unsigned char *out, size_t olen)
213 {
214 if (out)
215 {
216 OPENSSL_cleanse(out, olen);
217 OPENSSL_free(out);
218 }
219 }
220
221 /* Set "additional input" when generating random data. This uses the
222 * current PID, a time value and a counter.
223 */
224
225 static size_t drbg_get_adin(DRBG_CTX *ctx, unsigned char **pout)
226 {
227 /* Use of static variables is OK as this happens under a lock */
228 static unsigned char buf[16];
229 static unsigned long counter;
230 FIPS_get_timevec(buf, &counter);
231 *pout = buf;
232 return sizeof(buf);
233 }
234
235 /* RAND_add() and RAND_seed() pass through to OpenSSL PRNG so it is
236 * correctly seeded by RAND_poll().
237 */
238
239 static int drbg_rand_add(DRBG_CTX *ctx, const void *in, int inlen,
240 double entropy)
241 {
242 RAND_SSLeay()->add(in, inlen, entropy);
243 return 1;
244 }
245
246 static int drbg_rand_seed(DRBG_CTX *ctx, const void *in, int inlen)
247 {
248 RAND_SSLeay()->seed(in, inlen);
249 return 1;
250 }
251
252 #ifndef OPENSSL_DRBG_DEFAULT_TYPE
253 #define OPENSSL_DRBG_DEFAULT_TYPE NID_aes_256_ctr
254 #endif
255 #ifndef OPENSSL_DRBG_DEFAULT_FLAGS
256 #define OPENSSL_DRBG_DEFAULT_FLAGS DRBG_FLAG_CTR_USE_DF
257 #endif
258
259 static int fips_drbg_type = OPENSSL_DRBG_DEFAULT_TYPE;
260 static int fips_drbg_flags = OPENSSL_DRBG_DEFAULT_FLAGS;
261
262 void RAND_set_fips_drbg_type(int type, int flags)
263 {
264 fips_drbg_type = type;
265 fips_drbg_flags = flags;
266 }
267
268 int RAND_init_fips(void)
269 {
270 DRBG_CTX *dctx;
271 size_t plen;
272 unsigned char pers[32], *p;
273 #ifndef OPENSSL_ALLOW_DUAL_EC_DRBG
274 if (fips_drbg_type >> 16)
275 {
276 RANDerr(RAND_F_RAND_INIT_FIPS, RAND_R_DUAL_EC_DRBG_DISABLED);
277 return 0;
278 }
279 #endif
280
281 dctx = FIPS_get_default_drbg();
282 if (FIPS_drbg_init(dctx, fips_drbg_type, fips_drbg_flags) <= 0)
283 {
284 RANDerr(RAND_F_RAND_INIT_FIPS, RAND_R_ERROR_INITIALISING_DRBG);
285 return 0;
286 }
287
288 FIPS_drbg_set_callbacks(dctx,
289 drbg_get_entropy, drbg_free_entropy, 20,
290 drbg_get_entropy, drbg_free_entropy);
291 FIPS_drbg_set_rand_callbacks(dctx, drbg_get_adin, 0,
292 drbg_rand_seed, drbg_rand_add);
293 /* Personalisation string: a string followed by date time vector */
294 strcpy((char *)pers, "OpenSSL DRBG2.0");
295 plen = drbg_get_adin(dctx, &p);
296 memcpy(pers + 16, p, plen);
297
298 if (FIPS_drbg_instantiate(dctx, pers, sizeof(pers)) <= 0)
299 {
300 RANDerr(RAND_F_RAND_INIT_FIPS, RAND_R_ERROR_INSTANTIATING_DRBG);
301 return 0;
302 }
303 FIPS_rand_set_method(FIPS_drbg_method());
304 return 1;
305 }
306
307 #endif