crypto/openssl/crypto/srp/srp_vfy.c

   1 /* crypto/srp/srp_vfy.c */
   2 /* Written by Christophe Renou (christophe.renou@edelweb.fr) with
   3  * the precious help of Peter Sylvester (peter.sylvester@edelweb.fr)
   4  * for the EdelKey project and contributed to the OpenSSL project 2004.
   5  */
   6 /* ====================================================================
   7  * Copyright (c) 2004 The OpenSSL Project.  All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  *
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  *
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in
  18  *    the documentation and/or other materials provided with the
  19  *    distribution.
  20  *
  21  * 3. All advertising materials mentioning features or use of this
  22  *    software must display the following acknowledgment:
  23  *    "This product includes software developed by the OpenSSL Project
  24  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
  25  *
  26  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  27  *    endorse or promote products derived from this software without
  28  *    prior written permission. For written permission, please contact
  29  *    licensing@OpenSSL.org.
  30  *
  31  * 5. Products derived from this software may not be called "OpenSSL"
  32  *    nor may "OpenSSL" appear in their names without prior written
  33  *    permission of the OpenSSL Project.
  34  *
  35  * 6. Redistributions of any form whatsoever must retain the following
  36  *    acknowledgment:
  37  *    "This product includes software developed by the OpenSSL Project
  38  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
  39  *
  40  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  41  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  43  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  44  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  45  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  46  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  47  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  49  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  50  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  51  * OF THE POSSIBILITY OF SUCH DAMAGE.
  52  * ====================================================================
  53  *
  54  * This product includes cryptographic software written by Eric Young
  55  * (eay@cryptsoft.com).  This product includes software written by Tim
  56  * Hudson (tjh@cryptsoft.com).
  57  *
  58  */
  59 #ifndef OPENSSL_NO_SRP
  60 #include "cryptlib.h"
  61 #include "srp_lcl.h"
  62 #include <openssl/srp.h>
  63 #include <openssl/evp.h>
  64 #include <openssl/buffer.h>
  65 #include <openssl/rand.h>
  66 #include <openssl/txt_db.h>
  67
  68 #define SRP_RANDOM_SALT_LEN 20
  69 #define MAX_LEN 2500
  70
  71 static char b64table[] =
  72   "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz./";
  73
  74 /* the following two conversion routines have been inspired by code from Stanford */
  75
  76 /*
  77  * Convert a base64 string into raw byte array representation.
  78  */
  79 static int t_fromb64(unsigned char *a, const char *src)
  80         {
  81         char *loc;
  82         int i, j;
  83         int size;
  84
  85         while(*src && (*src == ' ' || *src == '\t' || *src == '\n'))
  86                 ++src;
  87         size = strlen(src);
  88         i = 0;
  89         while(i < size)
  90                 {
  91                 loc = strchr(b64table, src[i]);
  92                 if(loc == (char *) 0) break;
  93                 else a[i] = loc - b64table;
  94                 ++i;
  95                 }
  96         size = i;
  97         i = size - 1;
  98         j = size;
  99         while(1)
 100                 {
 101                 a[j] = a[i];
 102                 if(--i < 0) break;
 103                 a[j] |= (a[i] & 3) << 6;
 104                 --j;
 105                 a[j] = (unsigned char) ((a[i] & 0x3c) >> 2);
 106                 if(--i < 0) break;
 107                 a[j] |= (a[i] & 0xf) << 4;
 108                 --j;
 109                 a[j] = (unsigned char) ((a[i] & 0x30) >> 4);
 110                 if(--i < 0) break;
 111                 a[j] |= (a[i] << 2);
 112
 113                 a[--j] = 0;
 114                 if(--i < 0) break;
 115                 }
 116         while(a[j] == 0 && j <= size) ++j;
 117         i = 0;
 118         while (j <= size) a[i++] = a[j++];
 119         return i;
 120         }
 121
 122
 123 /*
 124  * Convert a raw byte string into a null-terminated base64 ASCII string.
 125  */
 126 static char *t_tob64(char *dst, const unsigned char *src, int size)
 127         {
 128         int c, pos = size % 3;
 129         unsigned char b0 = 0, b1 = 0, b2 = 0, notleading = 0;
 130         char *olddst = dst;
 131
 132         switch(pos)
 133                 {
 134         case 1:
 135                 b2 = src[0];
 136                 break;
 137         case 2:
 138                 b1 = src[0];
 139                 b2 = src[1];
 140                 break;
 141                 }
 142
 143         while(1)
 144                 {
 145                 c = (b0 & 0xfc) >> 2;
 146                 if(notleading || c != 0)
 147                         {
 148                         *dst++ = b64table[c];
 149                         notleading = 1;
 150                         }
 151                 c = ((b0 & 3) << 4) | ((b1 & 0xf0) >> 4);
 152                 if(notleading || c != 0)
 153                         {
 154                         *dst++ = b64table[c];
 155                         notleading = 1;
 156                         }
 157                 c = ((b1 & 0xf) << 2) | ((b2 & 0xc0) >> 6);
 158                 if(notleading || c != 0)
 159                         {
 160                         *dst++ = b64table[c];
 161                         notleading = 1;
 162                         }
 163                 c = b2 & 0x3f;
 164                 if(notleading || c != 0)
 165                         {
 166                         *dst++ = b64table[c];
 167                         notleading = 1;
 168                         }
 169                 if(pos >= size) break;
 170                 else
 171                         {
 172                         b0 = src[pos++];
 173                         b1 = src[pos++];
 174                         b2 = src[pos++];
 175                         }
 176                 }
 177
 178         *dst++ = '\0';
 179         return olddst;
 180         }
 181
 182 static void SRP_user_pwd_free(SRP_user_pwd *user_pwd)
 183         {
 184         if (user_pwd == NULL)
 185                 return;
 186         BN_free(user_pwd->s);
 187         BN_clear_free(user_pwd->v);
 188         OPENSSL_free(user_pwd->id);
 189         OPENSSL_free(user_pwd->info);
 190         OPENSSL_free(user_pwd);
 191         }
 192
 193 static SRP_user_pwd *SRP_user_pwd_new()
 194         {
 195         SRP_user_pwd *ret = OPENSSL_malloc(sizeof(SRP_user_pwd));
 196         if (ret == NULL)
 197                 return NULL;
 198         ret->N = NULL;
 199         ret->g = NULL;
 200         ret->s = NULL;
 201         ret->v = NULL;
 202         ret->id = NULL ;
 203         ret->info = NULL;
 204         return ret;
 205         }
 206
 207 static void SRP_user_pwd_set_gN(SRP_user_pwd *vinfo, const BIGNUM *g,
 208                                 const BIGNUM *N)
 209         {
 210         vinfo->N = N;
 211         vinfo->g = g;
 212         }
 213
 214 static int SRP_user_pwd_set_ids(SRP_user_pwd *vinfo, const char *id,
 215                                 const char *info)
 216         {
 217         if (id != NULL && NULL == (vinfo->id = BUF_strdup(id)))
 218                 return 0;
 219         return (info == NULL || NULL != (vinfo->info = BUF_strdup(info))) ;
 220         }
 221
 222 static int SRP_user_pwd_set_sv(SRP_user_pwd *vinfo, const char *s,
 223                                const char *v)
 224         {
 225         unsigned char tmp[MAX_LEN];
 226         int len;
 227
 228         if (strlen(s) > MAX_LEN || strlen(v) > MAX_LEN)
 229                 return 0;
 230         len = t_fromb64(tmp, v);
 231         if (NULL == (vinfo->v = BN_bin2bn(tmp, len, NULL)) )
 232                 return 0;
 233         len = t_fromb64(tmp, s);
 234         return ((vinfo->s = BN_bin2bn(tmp, len, NULL)) != NULL) ;
 235         }
 236
 237 static int SRP_user_pwd_set_sv_BN(SRP_user_pwd *vinfo, BIGNUM *s, BIGNUM *v)
 238         {
 239         vinfo->v = v;
 240         vinfo->s = s;
 241         return (vinfo->s != NULL && vinfo->v != NULL) ;
 242         }
 243
 244 SRP_VBASE *SRP_VBASE_new(char *seed_key)
 245         {
 246         SRP_VBASE *vb = (SRP_VBASE *) OPENSSL_malloc(sizeof(SRP_VBASE));
 247
 248         if (vb == NULL)
 249                 return NULL;
 250         if (!(vb->users_pwd = sk_SRP_user_pwd_new_null()) ||
 251                 !(vb->gN_cache = sk_SRP_gN_cache_new_null()))
 252                 {
 253                 OPENSSL_free(vb);
 254                 return NULL;
 255                 }
 256         vb->default_g = NULL;
 257         vb->default_N = NULL;
 258         vb->seed_key = NULL;
 259         if ((seed_key != NULL) &&
 260                 (vb->seed_key = BUF_strdup(seed_key)) == NULL)
 261                 {
 262                 sk_SRP_user_pwd_free(vb->users_pwd);
 263                 sk_SRP_gN_cache_free(vb->gN_cache);
 264                 OPENSSL_free(vb);
 265                 return NULL;
 266                 }
 267         return vb;
 268         }
 269
 270
 271 int SRP_VBASE_free(SRP_VBASE *vb)
 272         {
 273         sk_SRP_user_pwd_pop_free(vb->users_pwd,SRP_user_pwd_free);
 274         sk_SRP_gN_cache_free(vb->gN_cache);
 275         OPENSSL_free(vb->seed_key);
 276         OPENSSL_free(vb);
 277         return 0;
 278         }
 279
 280
 281 static SRP_gN_cache *SRP_gN_new_init(const char *ch)
 282         {
 283         unsigned char tmp[MAX_LEN];
 284         int len;
 285
 286         SRP_gN_cache *newgN = (SRP_gN_cache *)OPENSSL_malloc(sizeof(SRP_gN_cache));
 287         if (newgN == NULL)
 288                 return NULL;
 289
 290         if ((newgN->b64_bn = BUF_strdup(ch)) == NULL)
 291                 goto err;
 292
 293         len = t_fromb64(tmp, ch);
 294         if ((newgN->bn = BN_bin2bn(tmp, len, NULL)))
 295                 return newgN;
 296
 297         OPENSSL_free(newgN->b64_bn);
 298 err:
 299         OPENSSL_free(newgN);
 300         return NULL;
 301         }
 302
 303
 304 static void SRP_gN_free(SRP_gN_cache *gN_cache)
 305         {
 306         if (gN_cache == NULL)
 307                 return;
 308         OPENSSL_free(gN_cache->b64_bn);
 309         BN_free(gN_cache->bn);
 310         OPENSSL_free(gN_cache);
 311         }
 312
 313 static SRP_gN *SRP_get_gN_by_id(const char *id, STACK_OF(SRP_gN) *gN_tab)
 314         {
 315         int i;
 316
 317         SRP_gN *gN;
 318         if (gN_tab != NULL)
 319         for(i = 0; i < sk_SRP_gN_num(gN_tab); i++)
 320                 {
 321                 gN = sk_SRP_gN_value(gN_tab, i);
 322                 if (gN && (id == NULL || strcmp(gN->id,id)==0))
 323                         return gN;
 324                 }
 325
 326         return SRP_get_default_gN(id);
 327         }
 328
 329 static BIGNUM *SRP_gN_place_bn(STACK_OF(SRP_gN_cache) *gN_cache, char *ch)
 330         {
 331         int i;
 332         if (gN_cache == NULL)
 333                 return NULL;
 334
 335         /* search if we have already one... */
 336         for(i = 0; i < sk_SRP_gN_cache_num(gN_cache); i++)
 337                 {
 338                 SRP_gN_cache *cache = sk_SRP_gN_cache_value(gN_cache, i);
 339                 if (strcmp(cache->b64_bn,ch)==0)
 340                         return cache->bn;
 341                 }
 342                 {               /* it is the first time that we find it */
 343                 SRP_gN_cache *newgN = SRP_gN_new_init(ch);
 344                 if (newgN)
 345                         {
 346                         if (sk_SRP_gN_cache_insert(gN_cache,newgN,0)>0)
 347                                 return newgN->bn;
 348                         SRP_gN_free(newgN);
 349                         }
 350                 }
 351         return NULL;
 352         }
 353
 354 /* this function parses verifier file. Format is:
 355  * string(index):base64(N):base64(g):0
 356  * string(username):base64(v):base64(salt):int(index)
 357  */
 358
 359
 360 int SRP_VBASE_init(SRP_VBASE *vb, char *verifier_file)
 361         {
 362         int error_code ;
 363         STACK_OF(SRP_gN) *SRP_gN_tab = sk_SRP_gN_new_null();
 364         char *last_index = NULL;
 365         int i;
 366         char **pp;
 367
 368         SRP_gN *gN = NULL;
 369         SRP_user_pwd *user_pwd = NULL ;
 370
 371         TXT_DB *tmpdb = NULL;
 372         BIO *in = BIO_new(BIO_s_file());
 373
 374         error_code = SRP_ERR_OPEN_FILE;
 375
 376         if (in == NULL || BIO_read_filename(in,verifier_file) <= 0)
 377                 goto err;
 378
 379         error_code = SRP_ERR_VBASE_INCOMPLETE_FILE;
 380
 381         if ((tmpdb =TXT_DB_read(in,DB_NUMBER)) == NULL)
 382                 goto err;
 383
 384         error_code = SRP_ERR_MEMORY;
 385
 386
 387         if (vb->seed_key)
 388                 {
 389                 last_index = SRP_get_default_gN(NULL)->id;
 390                 }
 391         for (i = 0; i < sk_OPENSSL_PSTRING_num(tmpdb->data); i++)
 392                 {
 393                 pp = (char **)sk_OPENSSL_PSTRING_value(tmpdb->data,i);
 394                 if (pp[DB_srptype][0] == DB_SRP_INDEX)
 395                         {
 396                         /*we add this couple in the internal Stack */
 397
 398                         if ((gN = (SRP_gN *)OPENSSL_malloc(sizeof(SRP_gN))) == NULL)
 399                                 goto err;
 400
 401                         if  (!(gN->id = BUF_strdup(pp[DB_srpid]))
 402                         ||  !(gN->N = SRP_gN_place_bn(vb->gN_cache,pp[DB_srpverifier]))
 403                         ||  !(gN->g = SRP_gN_place_bn(vb->gN_cache,pp[DB_srpsalt]))
 404                         ||  sk_SRP_gN_insert(SRP_gN_tab,gN,0) == 0)
 405                                 goto err;
 406
 407                         gN = NULL;
 408
 409                         if (vb->seed_key != NULL)
 410                                 {
 411                                 last_index = pp[DB_srpid];
 412                                 }
 413                         }
 414                 else if (pp[DB_srptype][0] == DB_SRP_VALID)
 415                         {
 416                         /* it is a user .... */
 417                         SRP_gN *lgN;
 418                         if ((lgN = SRP_get_gN_by_id(pp[DB_srpgN],SRP_gN_tab))!=NULL)
 419                                 {
 420                                 error_code = SRP_ERR_MEMORY;
 421                                 if ((user_pwd = SRP_user_pwd_new()) == NULL)
 422                                         goto err;
 423
 424                                 SRP_user_pwd_set_gN(user_pwd,lgN->g,lgN->N);
 425                                 if (!SRP_user_pwd_set_ids(user_pwd, pp[DB_srpid],pp[DB_srpinfo]))
 426                                         goto err;
 427
 428                                 error_code = SRP_ERR_VBASE_BN_LIB;
 429                                 if (!SRP_user_pwd_set_sv(user_pwd, pp[DB_srpsalt],pp[DB_srpverifier]))
 430                                         goto err;
 431
 432                                 if (sk_SRP_user_pwd_insert(vb->users_pwd, user_pwd, 0) == 0)
 433                                         goto err;
 434                                 user_pwd = NULL; /* abandon responsability */
 435                                 }
 436                         }
 437                 }
 438
 439         if (last_index != NULL)
 440                 {
 441                 /* this means that we want to simulate a default user */
 442
 443                 if (((gN = SRP_get_gN_by_id(last_index,SRP_gN_tab))==NULL))
 444                         {
 445                         error_code = SRP_ERR_VBASE_BN_LIB;
 446                         goto err;
 447                         }
 448                 vb->default_g = gN->g ;
 449                 vb->default_N = gN->N ;
 450                 gN = NULL ;
 451                 }
 452         error_code = SRP_NO_ERROR;
 453
 454  err:
 455         /* there may be still some leaks to fix, if this fails, the application terminates most likely */
 456
 457         if (gN != NULL)
 458                 {
 459                 OPENSSL_free(gN->id);
 460                 OPENSSL_free(gN);
 461                 }
 462
 463         SRP_user_pwd_free(user_pwd);
 464
 465         if (tmpdb) TXT_DB_free(tmpdb);
 466         if (in) BIO_free_all(in);
 467
 468         sk_SRP_gN_free(SRP_gN_tab);
 469
 470         return error_code;
 471
 472         }
 473
 474
 475 SRP_user_pwd *SRP_VBASE_get_by_user(SRP_VBASE *vb, char *username)
 476         {
 477         int i;
 478         SRP_user_pwd *user;
 479         unsigned char digv[SHA_DIGEST_LENGTH];
 480         unsigned char digs[SHA_DIGEST_LENGTH];
 481         EVP_MD_CTX ctxt;
 482
 483         if (vb == NULL)
 484                 return NULL;
 485         for(i = 0; i < sk_SRP_user_pwd_num(vb->users_pwd); i++)
 486                 {
 487                 user = sk_SRP_user_pwd_value(vb->users_pwd, i);
 488                 if (strcmp(user->id,username)==0)
 489                         return user;
 490                 }
 491         if ((vb->seed_key == NULL) ||
 492                 (vb->default_g == NULL) ||
 493                 (vb->default_N == NULL))
 494                 return NULL;
 495
 496 /* if the user is unknown we set parameters as well if we have a seed_key */
 497
 498         if ((user = SRP_user_pwd_new()) == NULL)
 499                 return NULL;
 500
 501         SRP_user_pwd_set_gN(user,vb->default_g,vb->default_N);
 502
 503         if (!SRP_user_pwd_set_ids(user,username,NULL))
 504                 goto err;
 505
 506         RAND_pseudo_bytes(digv, SHA_DIGEST_LENGTH);
 507         EVP_MD_CTX_init(&ctxt);
 508         EVP_DigestInit_ex(&ctxt, EVP_sha1(), NULL);
 509         EVP_DigestUpdate(&ctxt, vb->seed_key, strlen(vb->seed_key));
 510         EVP_DigestUpdate(&ctxt, username, strlen(username));
 511         EVP_DigestFinal_ex(&ctxt, digs, NULL);
 512         EVP_MD_CTX_cleanup(&ctxt);
 513         if (SRP_user_pwd_set_sv_BN(user, BN_bin2bn(digs,SHA_DIGEST_LENGTH,NULL), BN_bin2bn(digv,SHA_DIGEST_LENGTH, NULL)))
 514                 return user;
 515
 516 err:    SRP_user_pwd_free(user);
 517         return NULL;
 518         }
 519
 520
 521 /*
 522    create a verifier (*salt,*verifier,g and N are in base64)
 523 */
 524 char *SRP_create_verifier(const char *user, const char *pass, char **salt,
 525                           char **verifier, const char *N, const char *g)
 526         {
 527         int len;
 528         char * result=NULL;
 529         char *vf;
 530         BIGNUM *N_bn = NULL, *g_bn = NULL, *s = NULL, *v = NULL;
 531         unsigned char tmp[MAX_LEN];
 532         unsigned char tmp2[MAX_LEN];
 533         char * defgNid = NULL;
 534
 535         if ((user == NULL)||
 536                 (pass == NULL)||
 537                 (salt == NULL)||
 538                 (verifier == NULL))
 539                 goto err;
 540
 541         if (N)
 542                 {
 543                 if (!(len = t_fromb64(tmp, N))) goto err;
 544                 N_bn = BN_bin2bn(tmp, len, NULL);
 545                 if (!(len = t_fromb64(tmp, g))) goto err;
 546                 g_bn = BN_bin2bn(tmp, len, NULL);
 547                 defgNid = "*";
 548                 }
 549         else
 550                 {
 551                 SRP_gN * gN = SRP_get_gN_by_id(g, NULL) ;
 552                 if (gN == NULL)
 553                         goto err;
 554                 N_bn = gN->N;
 555                 g_bn = gN->g;
 556                 defgNid = gN->id;
 557                 }
 558
 559         if (*salt == NULL)
 560                 {
 561                 RAND_pseudo_bytes(tmp2, SRP_RANDOM_SALT_LEN);
 562
 563                 s = BN_bin2bn(tmp2, SRP_RANDOM_SALT_LEN, NULL);
 564                 }
 565         else
 566                 {
 567                 if (!(len = t_fromb64(tmp2, *salt)))
 568                         goto err;
 569                 s = BN_bin2bn(tmp2, len, NULL);
 570                 }
 571
 572
 573         if(!SRP_create_verifier_BN(user, pass, &s, &v, N_bn, g_bn)) goto err;
 574
 575         BN_bn2bin(v,tmp);
 576         if (((vf = OPENSSL_malloc(BN_num_bytes(v)*2)) == NULL))
 577                 goto err;
 578         t_tob64(vf, tmp, BN_num_bytes(v));
 579
 580         *verifier = vf;
 581         if (*salt == NULL)
 582                 {
 583                 char *tmp_salt;
 584                 if ((tmp_salt = (char *)OPENSSL_malloc(SRP_RANDOM_SALT_LEN * 2)) == NULL)
 585                         {
 586                         OPENSSL_free(vf);
 587                         goto err;
 588                         }
 589                 t_tob64(tmp_salt, tmp2, SRP_RANDOM_SALT_LEN);
 590                 *salt = tmp_salt;
 591                 }
 592
 593         result=defgNid;
 594
 595 err:
 596         if(N)
 597                 {
 598                 BN_free(N_bn);
 599                 BN_free(g_bn);
 600                 }
 601         return result;
 602         }
 603
 604 /*
 605    create a verifier (*salt,*verifier,g and N are BIGNUMs)
 606 */
 607 int SRP_create_verifier_BN(const char *user, const char *pass, BIGNUM **salt, BIGNUM **verifier, BIGNUM *N, BIGNUM *g)
 608         {
 609         int result=0;
 610         BIGNUM *x = NULL;
 611         BN_CTX *bn_ctx = BN_CTX_new();
 612         unsigned char tmp2[MAX_LEN];
 613
 614         if ((user == NULL)||
 615                 (pass == NULL)||
 616                 (salt == NULL)||
 617                 (verifier == NULL)||
 618                 (N == NULL)||
 619                 (g == NULL)||
 620                 (bn_ctx == NULL))
 621                 goto err;
 622
 623         srp_bn_print(N);
 624         srp_bn_print(g);
 625
 626         if (*salt == NULL)
 627                 {
 628                 RAND_pseudo_bytes(tmp2, SRP_RANDOM_SALT_LEN);
 629
 630                 *salt = BN_bin2bn(tmp2,SRP_RANDOM_SALT_LEN,NULL);
 631                 }
 632
 633         x = SRP_Calc_x(*salt,user,pass);
 634
 635         *verifier = BN_new();
 636         if(*verifier == NULL) goto err;
 637
 638         if (!BN_mod_exp(*verifier,g,x,N,bn_ctx))
 639                 {
 640                 BN_clear_free(*verifier);
 641                 goto err;
 642                 }
 643
 644         srp_bn_print(*verifier);
 645
 646         result=1;
 647
 648 err:
 649
 650         BN_clear_free(x);
 651         BN_CTX_free(bn_ctx);
 652         return result;
 653         }
 654
 655
 656
 657 #endif