crypto/openssl-0.9.7e/fips/dsa/fips_dsa_gen.c

   1 /* crypto/dsa/dsa_gen.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 #undef GENUINE_DSA
  60
  61 #ifdef GENUINE_DSA
  62 /* Parameter generation follows the original release of FIPS PUB 186,
  63  * Appendix 2.2 (i.e. use SHA as defined in FIPS PUB 180) */
  64 #define HASH    EVP_sha()
  65 #else
  66 /* Parameter generation follows the updated Appendix 2.2 for FIPS PUB 186,
  67  * also Appendix 2.2 of FIPS PUB 186-1 (i.e. use SHA as defined in
  68  * FIPS PUB 180-1) */
  69 #define HASH    EVP_sha1()
  70 #endif
  71
  72 #include <stdio.h>
  73 #include <string.h>
  74 #include <time.h>
  75 /*#include "cryptlib.h"*/
  76 #include <openssl/evp.h>
  77 #include <openssl/bn.h>
  78 #ifndef OPENSSL_NO_DSA
  79 #include <openssl/dsa.h>
  80 #endif
  81 #ifndef OPENSSL_NO_RAND
  82 #include <openssl/rand.h>
  83 #endif
  84 #ifndef OPENSSL_NO_SHA
  85 #include <openssl/sha.h>
  86 #endif
  87 #include <openssl/fips.h>
  88 #include <openssl/err.h>
  89
  90 #ifndef OPENSSL_NO_DSA
  91 #ifdef OPENSSL_FIPS
  92
  93 static int fips_check_dsa(DSA *dsa)
  94     {
  95     static const unsigned char str1[]="12345678901234567890";
  96     unsigned char sig[256];
  97     unsigned int siglen;
  98
  99     DSA_sign(0, str1, 20, sig, &siglen, dsa);
 100     if(DSA_verify(0, str1, 20, sig, siglen, dsa) != 1)
 101         {
 102         FIPSerr(FIPS_F_FIPS_CHECK_DSA,FIPS_R_PAIRWISE_TEST_FAILED);
 103         return 0;
 104         }
 105     return 1;
 106     }
 107
 108 DSA *DSA_generate_parameters(FIPS_DSA_SIZE_T bits,
 109                 unsigned char *seed_in, FIPS_DSA_SIZE_T seed_len,
 110                 int *counter_ret, unsigned long *h_ret,
 111                 void (*callback)(int, int, void *),
 112                 void *cb_arg)
 113         {
 114         int ok=0;
 115         unsigned char seed[SHA_DIGEST_LENGTH];
 116         unsigned char md[SHA_DIGEST_LENGTH];
 117         unsigned char buf[SHA_DIGEST_LENGTH],buf2[SHA_DIGEST_LENGTH];
 118         BIGNUM *r0,*W,*X,*c,*test;
 119         BIGNUM *g=NULL,*q=NULL,*p=NULL;
 120         BN_MONT_CTX *mont=NULL;
 121         int k,n=0,i,b,m=0;
 122         int counter=0;
 123         int r=0;
 124         BN_CTX *ctx=NULL,*ctx2=NULL,*ctx3=NULL;
 125         unsigned int h=2;
 126         DSA *ret=NULL;
 127         unsigned char *seed_out=seed_in;
 128
 129         if(FIPS_selftest_failed())
 130             {
 131             FIPSerr(FIPS_F_DSA_GENERATE_PARAMETERS,
 132                     FIPS_R_FIPS_SELFTEST_FAILED);
 133             goto err;
 134             }
 135
 136         if (bits < 512) bits=512;
 137         bits=(bits+63)/64*64;
 138
 139         if (seed_len < 20)
 140                 seed_in = NULL; /* seed buffer too small -- ignore */
 141         if (seed_len > 20)
 142                 seed_len = 20; /* App. 2.2 of FIPS PUB 186 allows larger SEED,
 143                                 * but our internal buffers are restricted to 160 bits*/
 144         if ((seed_in != NULL) && (seed_len == 20))
 145                 memcpy(seed,seed_in,seed_len);
 146
 147         if ((ctx=BN_CTX_new()) == NULL) goto err;
 148         if ((ctx2=BN_CTX_new()) == NULL) goto err;
 149         if ((ctx3=BN_CTX_new()) == NULL) goto err;
 150         if ((ret=DSA_new()) == NULL) goto err;
 151
 152         if ((mont=BN_MONT_CTX_new()) == NULL) goto err;
 153
 154         BN_CTX_start(ctx2);
 155         r0 = BN_CTX_get(ctx2);
 156         g = BN_CTX_get(ctx2);
 157         W = BN_CTX_get(ctx2);
 158         q = BN_CTX_get(ctx2);
 159         X = BN_CTX_get(ctx2);
 160         c = BN_CTX_get(ctx2);
 161         p = BN_CTX_get(ctx2);
 162         test = BN_CTX_get(ctx2);
 163
 164         BN_lshift(test,BN_value_one(),bits-1);
 165
 166         for (;;)
 167                 {
 168                 for (;;) /* find q */
 169                         {
 170                         int seed_is_random;
 171
 172                         /* step 1 */
 173                         if (callback != NULL) callback(0,m++,cb_arg);
 174
 175                         if (!seed_len)
 176                                 {
 177                                 if(RAND_pseudo_bytes(seed,SHA_DIGEST_LENGTH) < 0)
 178                                         goto err;
 179                                 seed_is_random = 1;
 180                                 }
 181                         else
 182                                 {
 183                                 seed_is_random = 0;
 184                                 seed_len=0; /* use random seed if 'seed_in' turns out to be bad*/
 185                                 }
 186                         memcpy(buf,seed,SHA_DIGEST_LENGTH);
 187                         memcpy(buf2,seed,SHA_DIGEST_LENGTH);
 188                         /* precompute "SEED + 1" for step 7: */
 189                         for (i=SHA_DIGEST_LENGTH-1; i >= 0; i--)
 190                                 {
 191                                 buf[i]++;
 192                                 if (buf[i] != 0) break;
 193                                 }
 194
 195                         /* step 2 */
 196                         EVP_Digest(seed,SHA_DIGEST_LENGTH,md,NULL,HASH, NULL);
 197                         EVP_Digest(buf,SHA_DIGEST_LENGTH,buf2,NULL,HASH, NULL);
 198                         for (i=0; i<SHA_DIGEST_LENGTH; i++)
 199                                 md[i]^=buf2[i];
 200
 201                         /* step 3 */
 202                         md[0]|=0x80;
 203                         md[SHA_DIGEST_LENGTH-1]|=0x01;
 204                         if (!BN_bin2bn(md,SHA_DIGEST_LENGTH,q)) goto err;
 205
 206                         /* step 4 */
 207                         r = BN_is_prime_fasttest(q, DSS_prime_checks, callback, ctx3, cb_arg, seed_is_random);
 208                         if (r > 0)
 209                                 break;
 210                         if (r != 0)
 211                                 goto err;
 212
 213                         /* do a callback call */
 214                         /* step 5 */
 215                         }
 216
 217                 if (callback != NULL) callback(2,0,cb_arg);
 218                 if (callback != NULL) callback(3,0,cb_arg);
 219
 220                 /* step 6 */
 221                 counter=0;
 222                 /* "offset = 2" */
 223
 224                 n=(bits-1)/160;
 225                 b=(bits-1)-n*160;
 226
 227                 for (;;)
 228                         {
 229                         if (callback != NULL && counter != 0)
 230                                 callback(0,counter,cb_arg);
 231
 232                         /* step 7 */
 233                         BN_zero(W);
 234                         /* now 'buf' contains "SEED + offset - 1" */
 235                         for (k=0; k<=n; k++)
 236                                 {
 237                                 /* obtain "SEED + offset + k" by incrementing: */
 238                                 for (i=SHA_DIGEST_LENGTH-1; i >= 0; i--)
 239                                         {
 240                                         buf[i]++;
 241                                         if (buf[i] != 0) break;
 242                                         }
 243
 244                                 EVP_Digest(buf,SHA_DIGEST_LENGTH,md,NULL,HASH, NULL);
 245
 246                                 /* step 8 */
 247                                 if (!BN_bin2bn(md,SHA_DIGEST_LENGTH,r0))
 248                                         goto err;
 249                                 BN_lshift(r0,r0,160*k);
 250                                 BN_add(W,W,r0);
 251                                 }
 252
 253                         /* more of step 8 */
 254                         BN_mask_bits(W,bits-1);
 255                         BN_copy(X,W); /* this should be ok */
 256                         BN_add(X,X,test); /* this should be ok */
 257
 258                         /* step 9 */
 259                         BN_lshift1(r0,q);
 260                         BN_mod(c,X,r0,ctx);
 261                         BN_sub(r0,c,BN_value_one());
 262                         BN_sub(p,X,r0);
 263
 264                         /* step 10 */
 265                         if (BN_cmp(p,test) >= 0)
 266                                 {
 267                                 /* step 11 */
 268                                 r = BN_is_prime_fasttest(p, DSS_prime_checks, callback, ctx3, cb_arg, 1);
 269                                 if (r > 0)
 270                                                 goto end; /* found it */
 271                                 if (r != 0)
 272                                         goto err;
 273                                 }
 274
 275                         /* step 13 */
 276                         counter++;
 277                         /* "offset = offset + n + 1" */
 278
 279                         /* step 14 */
 280                         if (counter >= 4096) break;
 281                         }
 282                 }
 283 end:
 284         if (callback != NULL) callback(2,1,cb_arg);
 285
 286         /* We now need to generate g */
 287         /* Set r0=(p-1)/q */
 288         BN_sub(test,p,BN_value_one());
 289         BN_div(r0,NULL,test,q,ctx);
 290
 291         BN_set_word(test,h);
 292         BN_MONT_CTX_set(mont,p,ctx);
 293
 294         for (;;)
 295                 {
 296                 /* g=test^r0%p */
 297                 BN_mod_exp_mont(g,test,r0,p,ctx,mont);
 298                 if (!BN_is_one(g)) break;
 299                 BN_add(test,test,BN_value_one());
 300                 h++;
 301                 }
 302
 303         if (callback != NULL) callback(3,1,cb_arg);
 304
 305         ok=1;
 306 err:
 307         if (!ok)
 308                 {
 309                 if (ret != NULL) DSA_free(ret);
 310                 }
 311         else
 312                 {
 313                 ret->p=BN_dup(p);
 314                 ret->q=BN_dup(q);
 315                 ret->g=BN_dup(g);
 316                 if(seed_out != NULL) memcpy(seed_out,seed,20);
 317                 if (counter_ret != NULL) *counter_ret=counter;
 318                 if (h_ret != NULL) *h_ret=h;
 319                 }
 320         if (ctx != NULL) BN_CTX_free(ctx);
 321         if (ctx2 != NULL)
 322                 {
 323                 BN_CTX_end(ctx2);
 324                 BN_CTX_free(ctx2);
 325                 }
 326         if (ctx3 != NULL) BN_CTX_free(ctx3);
 327         if (mont != NULL) BN_MONT_CTX_free(mont);
 328         return(ok?ret:NULL);
 329         }
 330
 331 int DSA_generate_key(DSA *dsa)
 332         {
 333         int ok=0;
 334         BN_CTX *ctx=NULL;
 335         BIGNUM *pub_key=NULL,*priv_key=NULL;
 336
 337         if ((ctx=BN_CTX_new()) == NULL) goto err;
 338
 339         if (dsa->priv_key == NULL)
 340                 {
 341                 if ((priv_key=BN_new()) == NULL) goto err;
 342                 }
 343         else
 344                 priv_key=dsa->priv_key;
 345
 346         do
 347                 if (!BN_rand_range(priv_key,dsa->q)) goto err;
 348         while (BN_is_zero(priv_key));
 349
 350         if (dsa->pub_key == NULL)
 351                 {
 352                 if ((pub_key=BN_new()) == NULL) goto err;
 353                 }
 354         else
 355                 pub_key=dsa->pub_key;
 356
 357         if (!BN_mod_exp(pub_key,dsa->g,priv_key,dsa->p,ctx)) goto err;
 358
 359         dsa->priv_key=priv_key;
 360         dsa->pub_key=pub_key;
 361
 362         if(!fips_check_dsa(dsa))
 363             goto err;
 364
 365         ok=1;
 366
 367 err:
 368         if ((pub_key != NULL) && (dsa->pub_key == NULL)) BN_free(pub_key);
 369         if ((priv_key != NULL) && (dsa->priv_key == NULL)) BN_free(priv_key);
 370         if (ctx != NULL) BN_CTX_free(ctx);
 371         return(ok);
 372         }
 373 #endif
 374 #endif