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 #endif
72
73 #ifndef OPENSSL_NO_ENGINE
74 /* non-NULL if default_RAND_meth is ENGINE-provided */
75 static ENGINE *funct_ref =NULL;
76 #endif
77 static const RAND_METHOD *default_RAND_meth = NULL;
78
RAND_set_rand_method(const RAND_METHOD * meth)79 int RAND_set_rand_method(const RAND_METHOD *meth)
80 {
81 #ifndef OPENSSL_NO_ENGINE
82 if(funct_ref)
83 {
84 ENGINE_finish(funct_ref);
85 funct_ref = NULL;
86 }
87 #endif
88 default_RAND_meth = meth;
89 return 1;
90 }
91
RAND_get_rand_method(void)92 const RAND_METHOD *RAND_get_rand_method(void)
93 {
94 if (!default_RAND_meth)
95 {
96 #ifndef OPENSSL_NO_ENGINE
97 ENGINE *e = ENGINE_get_default_RAND();
98 if(e)
99 {
100 default_RAND_meth = ENGINE_get_RAND(e);
101 if(!default_RAND_meth)
102 {
103 ENGINE_finish(e);
104 e = NULL;
105 }
106 }
107 if(e)
108 funct_ref = e;
109 else
110 #endif
111 default_RAND_meth = RAND_SSLeay();
112 }
113 return default_RAND_meth;
114 }
115
116 #ifndef OPENSSL_NO_ENGINE
RAND_set_rand_engine(ENGINE * engine)117 int RAND_set_rand_engine(ENGINE *engine)
118 {
119 const RAND_METHOD *tmp_meth = NULL;
120 if(engine)
121 {
122 if(!ENGINE_init(engine))
123 return 0;
124 tmp_meth = ENGINE_get_RAND(engine);
125 if(!tmp_meth)
126 {
127 ENGINE_finish(engine);
128 return 0;
129 }
130 }
131 /* This function releases any prior ENGINE so call it first */
132 RAND_set_rand_method(tmp_meth);
133 funct_ref = engine;
134 return 1;
135 }
136 #endif
137
RAND_cleanup(void)138 void RAND_cleanup(void)
139 {
140 const RAND_METHOD *meth = RAND_get_rand_method();
141 if (meth && meth->cleanup)
142 meth->cleanup();
143 RAND_set_rand_method(NULL);
144 }
145
RAND_seed(const void * buf,int num)146 void RAND_seed(const void *buf, int num)
147 {
148 const RAND_METHOD *meth = RAND_get_rand_method();
149 if (meth && meth->seed)
150 meth->seed(buf,num);
151 }
152
RAND_add(const void * buf,int num,double entropy)153 void RAND_add(const void *buf, int num, double entropy)
154 {
155 const RAND_METHOD *meth = RAND_get_rand_method();
156 if (meth && meth->add)
157 meth->add(buf,num,entropy);
158 }
159
RAND_bytes(unsigned char * buf,int num)160 int RAND_bytes(unsigned char *buf, int num)
161 {
162 const RAND_METHOD *meth = RAND_get_rand_method();
163 if (meth && meth->bytes)
164 return meth->bytes(buf,num);
165 return(-1);
166 }
167
RAND_pseudo_bytes(unsigned char * buf,int num)168 int RAND_pseudo_bytes(unsigned char *buf, int num)
169 {
170 const RAND_METHOD *meth = RAND_get_rand_method();
171 if (meth && meth->pseudorand)
172 return meth->pseudorand(buf,num);
173 return(-1);
174 }
175
RAND_status(void)176 int RAND_status(void)
177 {
178 const RAND_METHOD *meth = RAND_get_rand_method();
179 if (meth && meth->status)
180 return meth->status();
181 return 0;
182 }
183
184 #ifdef OPENSSL_FIPS
185
186 /* FIPS DRBG initialisation code. This sets up the DRBG for use by the
187 * rest of OpenSSL.
188 */
189
190 /* Entropy gatherer: use standard OpenSSL PRNG to seed (this will gather
191 * entropy internally through RAND_poll().
192 */
193
drbg_get_entropy(DRBG_CTX * ctx,unsigned char ** pout,int entropy,size_t min_len,size_t max_len)194 static size_t drbg_get_entropy(DRBG_CTX *ctx, unsigned char **pout,
195 int entropy, size_t min_len, size_t max_len)
196 {
197 /* Round up request to multiple of block size */
198 min_len = ((min_len + 19) / 20) * 20;
199 *pout = OPENSSL_malloc(min_len);
200 if (!*pout)
201 return 0;
202 if (RAND_SSLeay()->bytes(*pout, min_len) <= 0)
203 {
204 OPENSSL_free(*pout);
205 *pout = NULL;
206 return 0;
207 }
208 return min_len;
209 }
210
drbg_free_entropy(DRBG_CTX * ctx,unsigned char * out,size_t olen)211 static void drbg_free_entropy(DRBG_CTX *ctx, unsigned char *out, size_t olen)
212 {
213 OPENSSL_cleanse(out, olen);
214 OPENSSL_free(out);
215 }
216
217 /* Set "additional input" when generating random data. This uses the
218 * current PID, a time value and a counter.
219 */
220
drbg_get_adin(DRBG_CTX * ctx,unsigned char ** pout)221 static size_t drbg_get_adin(DRBG_CTX *ctx, unsigned char **pout)
222 {
223 /* Use of static variables is OK as this happens under a lock */
224 static unsigned char buf[16];
225 static unsigned long counter;
226 FIPS_get_timevec(buf, &counter);
227 *pout = buf;
228 return sizeof(buf);
229 }
230
231 /* RAND_add() and RAND_seed() pass through to OpenSSL PRNG so it is
232 * correctly seeded by RAND_poll().
233 */
234
drbg_rand_add(DRBG_CTX * ctx,const void * in,int inlen,double entropy)235 static int drbg_rand_add(DRBG_CTX *ctx, const void *in, int inlen,
236 double entropy)
237 {
238 RAND_SSLeay()->add(in, inlen, entropy);
239 return 1;
240 }
241
drbg_rand_seed(DRBG_CTX * ctx,const void * in,int inlen)242 static int drbg_rand_seed(DRBG_CTX *ctx, const void *in, int inlen)
243 {
244 RAND_SSLeay()->seed(in, inlen);
245 return 1;
246 }
247
248 #ifndef OPENSSL_DRBG_DEFAULT_TYPE
249 #define OPENSSL_DRBG_DEFAULT_TYPE NID_aes_256_ctr
250 #endif
251 #ifndef OPENSSL_DRBG_DEFAULT_FLAGS
252 #define OPENSSL_DRBG_DEFAULT_FLAGS DRBG_FLAG_CTR_USE_DF
253 #endif
254
255 static int fips_drbg_type = OPENSSL_DRBG_DEFAULT_TYPE;
256 static int fips_drbg_flags = OPENSSL_DRBG_DEFAULT_FLAGS;
257
RAND_set_fips_drbg_type(int type,int flags)258 void RAND_set_fips_drbg_type(int type, int flags)
259 {
260 fips_drbg_type = type;
261 fips_drbg_flags = flags;
262 }
263
RAND_init_fips(void)264 int RAND_init_fips(void)
265 {
266 DRBG_CTX *dctx;
267 size_t plen;
268 unsigned char pers[32], *p;
269 dctx = FIPS_get_default_drbg();
270 if (FIPS_drbg_init(dctx, fips_drbg_type, fips_drbg_flags) <= 0)
271 {
272 RANDerr(RAND_F_RAND_INIT_FIPS, RAND_R_ERROR_INITIALISING_DRBG);
273 return 0;
274 }
275
276 FIPS_drbg_set_callbacks(dctx,
277 drbg_get_entropy, drbg_free_entropy, 20,
278 drbg_get_entropy, drbg_free_entropy);
279 FIPS_drbg_set_rand_callbacks(dctx, drbg_get_adin, 0,
280 drbg_rand_seed, drbg_rand_add);
281 /* Personalisation string: a string followed by date time vector */
282 strcpy((char *)pers, "OpenSSL DRBG2.0");
283 plen = drbg_get_adin(dctx, &p);
284 memcpy(pers + 16, p, plen);
285
286 if (FIPS_drbg_instantiate(dctx, pers, sizeof(pers)) <= 0)
287 {
288 RANDerr(RAND_F_RAND_INIT_FIPS, RAND_R_ERROR_INSTANTIATING_DRBG);
289 return 0;
290 }
291 FIPS_rand_set_method(FIPS_drbg_method());
292 return 1;
293 }
294
295 #endif
296