release/src/router/openssl/crypto/rand/rand_lib.c

   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