ssl/tls_srp.c

   1 /* ssl/tls_srp.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 #include "ssl_locl.h"
  60 #ifndef OPENSSL_NO_SRP
  61
  62 #include <openssl/rand.h>
  63 #include <openssl/srp.h>
  64 #include <openssl/err.h>
  65
  66 int SSL_CTX_SRP_CTX_free(struct ssl_ctx_st *ctx)
  67         {
  68         if (ctx == NULL)
  69                 return 0;
  70         OPENSSL_free(ctx->srp_ctx.login);
  71         BN_free(ctx->srp_ctx.N);
  72         BN_free(ctx->srp_ctx.g);
  73         BN_free(ctx->srp_ctx.s);
  74         BN_free(ctx->srp_ctx.B);
  75         BN_free(ctx->srp_ctx.A);
  76         BN_free(ctx->srp_ctx.a);
  77         BN_free(ctx->srp_ctx.b);
  78         BN_free(ctx->srp_ctx.v);
  79         ctx->srp_ctx.TLS_ext_srp_username_callback = NULL;
  80         ctx->srp_ctx.SRP_cb_arg = NULL;
  81         ctx->srp_ctx.SRP_verify_param_callback = NULL;
  82         ctx->srp_ctx.SRP_give_srp_client_pwd_callback = NULL;
  83         ctx->srp_ctx.SRP_TLS_ext_missing_srp_client_username_callback = NULL;
  84         ctx->srp_ctx.N = NULL;
  85         ctx->srp_ctx.g = NULL;
  86         ctx->srp_ctx.s = NULL;
  87         ctx->srp_ctx.B = NULL;
  88         ctx->srp_ctx.A = NULL;
  89         ctx->srp_ctx.a = NULL;
  90         ctx->srp_ctx.b = NULL;
  91         ctx->srp_ctx.v = NULL;
  92         ctx->srp_ctx.login = NULL;
  93         ctx->srp_ctx.info = NULL;
  94         ctx->srp_ctx.strength = SRP_MINIMAL_N;
  95         ctx->srp_ctx.srp_Mask = 0;
  96         return (1);
  97         }
  98
  99 int SSL_SRP_CTX_free(struct ssl_st *s)
 100         {
 101         if (s == NULL)
 102                 return 0;
 103         OPENSSL_free(s->srp_ctx.login);
 104         BN_free(s->srp_ctx.N);
 105         BN_free(s->srp_ctx.g);
 106         BN_free(s->srp_ctx.s);
 107         BN_free(s->srp_ctx.B);
 108         BN_free(s->srp_ctx.A);
 109         BN_free(s->srp_ctx.a);
 110         BN_free(s->srp_ctx.b);
 111         BN_free(s->srp_ctx.v);
 112         s->srp_ctx.TLS_ext_srp_username_callback = NULL;
 113         s->srp_ctx.SRP_cb_arg = NULL;
 114         s->srp_ctx.SRP_verify_param_callback = NULL;
 115         s->srp_ctx.SRP_give_srp_client_pwd_callback = NULL;
 116         s->srp_ctx.SRP_TLS_ext_missing_srp_client_username_callback = NULL;
 117         s->srp_ctx.N = NULL;
 118         s->srp_ctx.g = NULL;
 119         s->srp_ctx.s = NULL;
 120         s->srp_ctx.B = NULL;
 121         s->srp_ctx.A = NULL;
 122         s->srp_ctx.a = NULL;
 123         s->srp_ctx.b = NULL;
 124         s->srp_ctx.v = NULL;
 125         s->srp_ctx.login = NULL;
 126         s->srp_ctx.info = NULL;
 127         s->srp_ctx.strength = SRP_MINIMAL_N;
 128         s->srp_ctx.srp_Mask = 0;
 129         return (1);
 130         }
 131
 132 int SSL_SRP_CTX_init(struct ssl_st *s)
 133         {
 134         SSL_CTX *ctx;
 135
 136         if ((s == NULL) || ((ctx = s->ctx) == NULL))
 137                 return 0;
 138         s->srp_ctx.SRP_cb_arg = ctx->srp_ctx.SRP_cb_arg;
 139         /* set client Hello login callback */
 140         s->srp_ctx.TLS_ext_srp_username_callback = ctx->srp_ctx.TLS_ext_srp_username_callback;
 141         /* set SRP N/g param callback for verification */
 142         s->srp_ctx.SRP_verify_param_callback = ctx->srp_ctx.SRP_verify_param_callback;
 143         /* set SRP client passwd callback */
 144         s->srp_ctx.SRP_give_srp_client_pwd_callback = ctx->srp_ctx.SRP_give_srp_client_pwd_callback;
 145         s->srp_ctx.SRP_TLS_ext_missing_srp_client_username_callback = ctx->srp_ctx.SRP_TLS_ext_missing_srp_client_username_callback;
 146
 147         s->srp_ctx.N = NULL;
 148         s->srp_ctx.g = NULL;
 149         s->srp_ctx.s = NULL;
 150         s->srp_ctx.B = NULL;
 151         s->srp_ctx.A = NULL;
 152         s->srp_ctx.a = NULL;
 153         s->srp_ctx.b = NULL;
 154         s->srp_ctx.v = NULL;
 155         s->srp_ctx.login = NULL;
 156         s->srp_ctx.info = ctx->srp_ctx.info;
 157         s->srp_ctx.strength = ctx->srp_ctx.strength;
 158
 159         if (((ctx->srp_ctx.N != NULL) &&
 160                  ((s->srp_ctx.N = BN_dup(ctx->srp_ctx.N)) == NULL)) ||
 161                 ((ctx->srp_ctx.g != NULL) &&
 162                  ((s->srp_ctx.g = BN_dup(ctx->srp_ctx.g)) == NULL)) ||
 163                 ((ctx->srp_ctx.s != NULL) &&
 164                  ((s->srp_ctx.s = BN_dup(ctx->srp_ctx.s)) == NULL)) ||
 165                 ((ctx->srp_ctx.B != NULL) &&
 166                  ((s->srp_ctx.B = BN_dup(ctx->srp_ctx.B)) == NULL)) ||
 167                 ((ctx->srp_ctx.A != NULL) &&
 168                  ((s->srp_ctx.A = BN_dup(ctx->srp_ctx.A)) == NULL)) ||
 169                 ((ctx->srp_ctx.a != NULL) &&
 170                  ((s->srp_ctx.a = BN_dup(ctx->srp_ctx.a)) == NULL)) ||
 171                 ((ctx->srp_ctx.v != NULL) &&
 172                  ((s->srp_ctx.v = BN_dup(ctx->srp_ctx.v)) == NULL)) ||
 173                 ((ctx->srp_ctx.b != NULL) &&
 174                  ((s->srp_ctx.b = BN_dup(ctx->srp_ctx.b)) == NULL)))
 175                 {
 176                 SSLerr(SSL_F_SSL_SRP_CTX_INIT,ERR_R_BN_LIB);
 177                 goto err;
 178                 }
 179         if ((ctx->srp_ctx.login != NULL) &&
 180                 ((s->srp_ctx.login = BUF_strdup(ctx->srp_ctx.login)) == NULL))
 181                 {
 182                 SSLerr(SSL_F_SSL_SRP_CTX_INIT,ERR_R_INTERNAL_ERROR);
 183                 goto err;
 184                 }
 185         s->srp_ctx.srp_Mask = ctx->srp_ctx.srp_Mask;
 186
 187         return (1);
 188 err:
 189         OPENSSL_free(s->srp_ctx.login);
 190         BN_free(s->srp_ctx.N);
 191         BN_free(s->srp_ctx.g);
 192         BN_free(s->srp_ctx.s);
 193         BN_free(s->srp_ctx.B);
 194         BN_free(s->srp_ctx.A);
 195         BN_free(s->srp_ctx.a);
 196         BN_free(s->srp_ctx.b);
 197         BN_free(s->srp_ctx.v);
 198         return (0);
 199         }
 200
 201 int SSL_CTX_SRP_CTX_init(struct ssl_ctx_st *ctx)
 202         {
 203         if (ctx == NULL)
 204                 return 0;
 205
 206         ctx->srp_ctx.SRP_cb_arg = NULL;
 207         /* set client Hello login callback */
 208         ctx->srp_ctx.TLS_ext_srp_username_callback = NULL;
 209         /* set SRP N/g param callback for verification */
 210         ctx->srp_ctx.SRP_verify_param_callback = NULL;
 211         /* set SRP client passwd callback */
 212         ctx->srp_ctx.SRP_give_srp_client_pwd_callback = NULL;
 213         ctx->srp_ctx.SRP_TLS_ext_missing_srp_client_username_callback = NULL;
 214
 215         ctx->srp_ctx.N = NULL;
 216         ctx->srp_ctx.g = NULL;
 217         ctx->srp_ctx.s = NULL;
 218         ctx->srp_ctx.B = NULL;
 219         ctx->srp_ctx.A = NULL;
 220         ctx->srp_ctx.a = NULL;
 221         ctx->srp_ctx.b = NULL;
 222         ctx->srp_ctx.v = NULL;
 223         ctx->srp_ctx.login = NULL;
 224         ctx->srp_ctx.srp_Mask = 0;
 225         ctx->srp_ctx.info = NULL;
 226         ctx->srp_ctx.strength = SRP_MINIMAL_N;
 227
 228         return (1);
 229         }
 230
 231 /* server side */
 232 int SSL_srp_server_param_with_username(SSL *s, int *ad)
 233         {
 234         unsigned char b[SSL_MAX_MASTER_KEY_LENGTH];
 235         int al;
 236
 237         *ad = SSL_AD_UNKNOWN_SRP_USERNAME;
 238         if ((s->srp_ctx.TLS_ext_srp_username_callback !=NULL) &&
 239                 ((al = s->srp_ctx.TLS_ext_srp_username_callback(s, ad, s->srp_ctx.SRP_cb_arg))!=SSL_ERROR_NONE))
 240                         return al;
 241
 242         *ad = SSL_AD_INTERNAL_ERROR;
 243         if ((s->srp_ctx.N == NULL) ||
 244                 (s->srp_ctx.g == NULL) ||
 245                 (s->srp_ctx.s == NULL) ||
 246                 (s->srp_ctx.v == NULL))
 247                 return SSL3_AL_FATAL;
 248
 249         RAND_bytes(b, sizeof(b));
 250         s->srp_ctx.b = BN_bin2bn(b,sizeof(b),NULL);
 251         OPENSSL_cleanse(b,sizeof(b));
 252
 253         /* Calculate:  B = (kv + g^b) % N  */
 254
 255         return ((s->srp_ctx.B = SRP_Calc_B(s->srp_ctx.b, s->srp_ctx.N, s->srp_ctx.g, s->srp_ctx.v)) != NULL)?
 256                         SSL_ERROR_NONE:SSL3_AL_FATAL;
 257         }
 258
 259 /* If the server just has the raw password, make up a verifier entry on the fly */
 260 int SSL_set_srp_server_param_pw(SSL *s, const char *user, const char *pass, const char *grp)
 261         {
 262         SRP_gN *GN = SRP_get_default_gN(grp);
 263         if(GN == NULL) return -1;
 264         s->srp_ctx.N = BN_dup(GN->N);
 265         s->srp_ctx.g = BN_dup(GN->g);
 266         if(s->srp_ctx.v != NULL)
 267                 {
 268                 BN_clear_free(s->srp_ctx.v);
 269                 s->srp_ctx.v = NULL;
 270                 }
 271         if(s->srp_ctx.s != NULL)
 272                 {
 273                 BN_clear_free(s->srp_ctx.s);
 274                 s->srp_ctx.s = NULL;
 275                 }
 276         if(!SRP_create_verifier_BN(user, pass, &s->srp_ctx.s, &s->srp_ctx.v, GN->N, GN->g)) return -1;
 277
 278         return 1;
 279         }
 280
 281 int SSL_set_srp_server_param(SSL *s, const BIGNUM *N, const BIGNUM *g,
 282                              BIGNUM *sa, BIGNUM *v, char *info)
 283         {
 284         if (N!= NULL)
 285                 {
 286                 if (s->srp_ctx.N != NULL)
 287                         {
 288                         if (!BN_copy(s->srp_ctx.N,N))
 289                                 {
 290                                 BN_free(s->srp_ctx.N);
 291                                 s->srp_ctx.N = NULL;
 292                                 }
 293                         }
 294                 else
 295                         s->srp_ctx.N = BN_dup(N);
 296                 }
 297         if (g!= NULL)
 298                 {
 299                 if (s->srp_ctx.g != NULL)
 300                         {
 301                         if (!BN_copy(s->srp_ctx.g,g))
 302                                 {
 303                                 BN_free(s->srp_ctx.g);
 304                                 s->srp_ctx.g = NULL;
 305                                 }
 306                         }
 307                 else
 308                         s->srp_ctx.g = BN_dup(g);
 309                 }
 310         if (sa!= NULL)
 311                 {
 312                 if (s->srp_ctx.s != NULL)
 313                         {
 314                         if (!BN_copy(s->srp_ctx.s,sa))
 315                                 {
 316                                 BN_free(s->srp_ctx.s);
 317                                 s->srp_ctx.s = NULL;
 318                                 }
 319                         }
 320                 else
 321                         s->srp_ctx.s = BN_dup(sa);
 322                 }
 323         if (v!= NULL)
 324                 {
 325                 if (s->srp_ctx.v != NULL)
 326                         {
 327                         if (!BN_copy(s->srp_ctx.v,v))
 328                                 {
 329                                 BN_free(s->srp_ctx.v);
 330                                 s->srp_ctx.v = NULL;
 331                                 }
 332                         }
 333                 else
 334                         s->srp_ctx.v = BN_dup(v);
 335                 }
 336         s->srp_ctx.info = info;
 337
 338         if (!(s->srp_ctx.N) ||
 339                 !(s->srp_ctx.g) ||
 340                 !(s->srp_ctx.s) ||
 341                 !(s->srp_ctx.v))
 342                 return -1;
 343
 344         return 1;
 345         }
 346
 347 int SRP_generate_server_master_secret(SSL *s,unsigned char *master_key)
 348         {
 349         BIGNUM *K = NULL, *u = NULL;
 350         int ret = -1, tmp_len;
 351         unsigned char *tmp = NULL;
 352
 353         if (!SRP_Verify_A_mod_N(s->srp_ctx.A,s->srp_ctx.N))
 354                 goto err;
 355         if (!(u = SRP_Calc_u(s->srp_ctx.A,s->srp_ctx.B,s->srp_ctx.N)))
 356                 goto err;
 357         if (!(K = SRP_Calc_server_key(s->srp_ctx.A, s->srp_ctx.v, u, s->srp_ctx.b, s->srp_ctx.N)))
 358                 goto err;
 359
 360         tmp_len = BN_num_bytes(K);
 361         if ((tmp = OPENSSL_malloc(tmp_len)) == NULL)
 362                 goto err;
 363         BN_bn2bin(K, tmp);
 364         ret = s->method->ssl3_enc->generate_master_secret(s,master_key,tmp,tmp_len);
 365 err:
 366         if (tmp)
 367                 {
 368                 OPENSSL_cleanse(tmp,tmp_len) ;
 369                 OPENSSL_free(tmp);
 370                 }
 371         BN_clear_free(K);
 372         BN_clear_free(u);
 373         return ret;
 374         }
 375
 376 /* client side */
 377 int SRP_generate_client_master_secret(SSL *s,unsigned char *master_key)
 378         {
 379         BIGNUM *x = NULL, *u = NULL, *K = NULL;
 380         int ret = -1, tmp_len;
 381         char *passwd = NULL;
 382         unsigned char *tmp = NULL;
 383
 384         /* Checks if b % n == 0
 385          */
 386         if (SRP_Verify_B_mod_N(s->srp_ctx.B,s->srp_ctx.N)==0) goto err;
 387         if (!(u = SRP_Calc_u(s->srp_ctx.A,s->srp_ctx.B,s->srp_ctx.N))) goto err;
 388         if (s->srp_ctx.SRP_give_srp_client_pwd_callback == NULL) goto err;
 389         if (!(passwd = s->srp_ctx.SRP_give_srp_client_pwd_callback(s, s->srp_ctx.SRP_cb_arg))) goto err;
 390         if (!(x = SRP_Calc_x(s->srp_ctx.s,s->srp_ctx.login,passwd))) goto err;
 391         if (!(K = SRP_Calc_client_key(s->srp_ctx.N, s->srp_ctx.B, s->srp_ctx.g, x, s->srp_ctx.a, u))) goto err;
 392
 393         tmp_len = BN_num_bytes(K);
 394         if ((tmp = OPENSSL_malloc(tmp_len)) == NULL) goto err;
 395         BN_bn2bin(K, tmp);
 396         ret = s->method->ssl3_enc->generate_master_secret(s,master_key,tmp,tmp_len);
 397 err:
 398         if (tmp)
 399                 {
 400                 OPENSSL_cleanse(tmp,tmp_len) ;
 401                 OPENSSL_free(tmp);
 402                 }
 403         BN_clear_free(K);
 404         BN_clear_free(x);
 405         if (passwd)
 406                 {
 407                 OPENSSL_cleanse(passwd,strlen(passwd)) ;
 408                 OPENSSL_free(passwd);
 409                 }
 410         BN_clear_free(u);
 411         return ret;
 412         }
 413
 414 int SRP_Calc_A_param(SSL *s)
 415         {
 416         unsigned char rnd[SSL_MAX_MASTER_KEY_LENGTH];
 417
 418         if (BN_num_bits(s->srp_ctx.N) < s->srp_ctx.strength)
 419                 return -1;
 420
 421         if (s->srp_ctx.SRP_verify_param_callback ==NULL &&
 422                 !SRP_check_known_gN_param(s->srp_ctx.g,s->srp_ctx.N))
 423                 return -1 ;
 424
 425         RAND_bytes(rnd, sizeof(rnd));
 426         s->srp_ctx.a = BN_bin2bn(rnd, sizeof(rnd), s->srp_ctx.a);
 427         OPENSSL_cleanse(rnd, sizeof(rnd));
 428
 429         if (!(s->srp_ctx.A = SRP_Calc_A(s->srp_ctx.a,s->srp_ctx.N,s->srp_ctx.g)))
 430                 return -1;
 431
 432         /* We can have a callback to verify SRP param!! */
 433         if (s->srp_ctx.SRP_verify_param_callback !=NULL)
 434                 return s->srp_ctx.SRP_verify_param_callback(s,s->srp_ctx.SRP_cb_arg);
 435
 436         return 1;
 437         }
 438
 439 int SRP_have_to_put_srp_username(SSL *s)
 440         {
 441         if (s->srp_ctx.SRP_TLS_ext_missing_srp_client_username_callback == NULL)
 442                 return 0;
 443         if ((s->srp_ctx.login = s->srp_ctx.SRP_TLS_ext_missing_srp_client_username_callback(s,s->srp_ctx.SRP_cb_arg)) == NULL)
 444                 return 0;
 445         s->srp_ctx.srp_Mask|=SSL_kSRP;
 446         return 1;
 447         }
 448
 449 BIGNUM *SSL_get_srp_g(SSL *s)
 450         {
 451         if (s->srp_ctx.g != NULL)
 452                 return s->srp_ctx.g;
 453         return s->ctx->srp_ctx.g;
 454         }
 455
 456 BIGNUM *SSL_get_srp_N(SSL *s)
 457         {
 458         if (s->srp_ctx.N != NULL)
 459                 return s->srp_ctx.N;
 460         return s->ctx->srp_ctx.N;
 461         }
 462
 463 char *SSL_get_srp_username(SSL *s)
 464         {
 465         if (s->srp_ctx.login != NULL)
 466                 return s->srp_ctx.login;
 467         return s->ctx->srp_ctx.login;
 468         }
 469
 470 char *SSL_get_srp_userinfo(SSL *s)
 471         {
 472         if (s->srp_ctx.info != NULL)
 473                 return s->srp_ctx.info;
 474         return s->ctx->srp_ctx.info;
 475         }
 476
 477 #define tls1_ctx_ctrl ssl3_ctx_ctrl
 478 #define tls1_ctx_callback_ctrl ssl3_ctx_callback_ctrl
 479
 480 int SSL_CTX_set_srp_username(SSL_CTX *ctx,char *name)
 481         {
 482         return tls1_ctx_ctrl(ctx,SSL_CTRL_SET_TLS_EXT_SRP_USERNAME,0,name);
 483         }
 484
 485 int SSL_CTX_set_srp_password(SSL_CTX *ctx,char *password)
 486         {
 487         return tls1_ctx_ctrl(ctx,SSL_CTRL_SET_TLS_EXT_SRP_PASSWORD,0,password);
 488         }
 489
 490 int SSL_CTX_set_srp_strength(SSL_CTX *ctx, int strength)
 491         {
 492         return tls1_ctx_ctrl(ctx, SSL_CTRL_SET_TLS_EXT_SRP_STRENGTH, strength,
 493                              NULL);
 494         }
 495
 496 int SSL_CTX_set_srp_verify_param_callback(SSL_CTX *ctx, int (*cb)(SSL *,void *))
 497         {
 498         return tls1_ctx_callback_ctrl(ctx,SSL_CTRL_SET_SRP_VERIFY_PARAM_CB,
 499                                       (void (*)(void))cb);
 500         }
 501
 502 int SSL_CTX_set_srp_cb_arg(SSL_CTX *ctx, void *arg)
 503         {
 504         return tls1_ctx_ctrl(ctx,SSL_CTRL_SET_SRP_ARG,0,arg);
 505         }
 506
 507 int SSL_CTX_set_srp_username_callback(SSL_CTX *ctx,
 508                                       int (*cb)(SSL *,int *,void *))
 509         {
 510         return tls1_ctx_callback_ctrl(ctx,SSL_CTRL_SET_TLS_EXT_SRP_USERNAME_CB,
 511                                       (void (*)(void))cb);
 512         }
 513
 514 int SSL_CTX_set_srp_client_pwd_callback(SSL_CTX *ctx, char *(*cb)(SSL *,void *))
 515         {
 516         return tls1_ctx_callback_ctrl(ctx,SSL_CTRL_SET_SRP_GIVE_CLIENT_PWD_CB,
 517                                       (void (*)(void))cb);
 518         }
 519
 520 int SSL_CTX_set_srp_missing_srp_username_callback(SSL_CTX *ctx,
 521                                                   char *(*cb)(SSL *,void *))
 522         {
 523         return tls1_ctx_callback_ctrl(ctx,
 524                             SSL_CTRL_SET_TLS_EXT_SRP_MISSING_CLIENT_USERNAME_CB,
 525                                       (void (*)(void))cb);
 526         }
 527 #endif