1 /* crypto/rand/rand_lib.c */ 2 /* Copyright (C) 1995-1998 Eric Young (eay (at) cryptsoft.com) 3 * All rights reserved. 4 * 5 * This package is an SSL implementation written 6 * by Eric Young (eay (at) 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 (at) 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 (at) 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 (at) 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 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 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 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 137 138 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 } 145 146 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 } 152 153 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 } 159 160 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 } 167 168 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 } 175 176 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 */ 193 194 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 } 210 211 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 */ 220 221 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 */ 234 235 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 } 241 242 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; 257 258 void RAND_set_fips_drbg_type(int type, int flags) 259 { 260 fips_drbg_type = type; 261 fips_drbg_flags = flags; 262 } 263 264 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
