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 #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         if (out)
 214                 {
 215                 OPENSSL_cleanse(out, olen);
 216                 OPENSSL_free(out);
 217                 }
 218         }
 219
 220 /* Set "additional input" when generating random data. This uses the
 221  * current PID, a time value and a counter.
 222  */
 223
 224 static size_t drbg_get_adin(DRBG_CTX *ctx, unsigned char **pout)
 225         {
 226         /* Use of static variables is OK as this happens under a lock */
 227         static unsigned char buf[16];
 228         static unsigned long counter;
 229         FIPS_get_timevec(buf, &counter);
 230         *pout = buf;
 231         return sizeof(buf);
 232         }
 233
 234 /* RAND_add() and RAND_seed() pass through to OpenSSL PRNG so it is
 235  * correctly seeded by RAND_poll().
 236  */
 237
 238 static int drbg_rand_add(DRBG_CTX *ctx, const void *in, int inlen,
 239                                 double entropy)
 240         {
 241         RAND_SSLeay()->add(in, inlen, entropy);
 242         return 1;
 243         }
 244
 245 static int drbg_rand_seed(DRBG_CTX *ctx, const void *in, int inlen)
 246         {
 247         RAND_SSLeay()->seed(in, inlen);
 248         return 1;
 249         }
 250
 251 #ifndef OPENSSL_DRBG_DEFAULT_TYPE
 252 #define OPENSSL_DRBG_DEFAULT_TYPE       NID_aes_256_ctr
 253 #endif
 254 #ifndef OPENSSL_DRBG_DEFAULT_FLAGS
 255 #define OPENSSL_DRBG_DEFAULT_FLAGS      DRBG_FLAG_CTR_USE_DF
 256 #endif
 257
 258 static int fips_drbg_type = OPENSSL_DRBG_DEFAULT_TYPE;
 259 static int fips_drbg_flags = OPENSSL_DRBG_DEFAULT_FLAGS;
 260
 261 void RAND_set_fips_drbg_type(int type, int flags)
 262         {
 263         fips_drbg_type = type;
 264         fips_drbg_flags = flags;
 265         }
 266
 267 int RAND_init_fips(void)
 268         {
 269         DRBG_CTX *dctx;
 270         size_t plen;
 271         unsigned char pers[32], *p;
 272         dctx = FIPS_get_default_drbg();
 273         if (FIPS_drbg_init(dctx, fips_drbg_type, fips_drbg_flags) <= 0)
 274                 {
 275                 RANDerr(RAND_F_RAND_INIT_FIPS, RAND_R_ERROR_INITIALISING_DRBG);
 276                 return 0;
 277                 }
 278
 279         FIPS_drbg_set_callbacks(dctx,
 280                                 drbg_get_entropy, drbg_free_entropy, 20,
 281                                 drbg_get_entropy, drbg_free_entropy);
 282         FIPS_drbg_set_rand_callbacks(dctx, drbg_get_adin, 0,
 283                                         drbg_rand_seed, drbg_rand_add);
 284         /* Personalisation string: a string followed by date time vector */
 285         strcpy((char *)pers, "OpenSSL DRBG2.0");
 286         plen = drbg_get_adin(dctx, &p);
 287         memcpy(pers + 16, p, plen);
 288
 289         if (FIPS_drbg_instantiate(dctx, pers, sizeof(pers)) <= 0)
 290                 {
 291                 RANDerr(RAND_F_RAND_INIT_FIPS, RAND_R_ERROR_INSTANTIATING_DRBG);
 292                 return 0;
 293                 }
 294         FIPS_rand_set_method(FIPS_drbg_method());
 295         return 1;
 296         }
 297
 298 #endif