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      1 /* ssl/tls_srp.c */
      2 /* Written by Christophe Renou (christophe.renou (at) edelweb.fr) with
      3  * the precious help of Peter Sylvester (peter.sylvester (at) edelweb.fr)
      4  * for the EdelKey project and contributed to the OpenSSL project 2004.
      5  */
      6 /* ====================================================================
      7  * Copyright (c) 2004-2011 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 (at) 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 (at) cryptsoft.com).  This product includes software written by Tim
     56  * Hudson (tjh (at) 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.N = NULL;
     84 	ctx->srp_ctx.g = NULL;
     85 	ctx->srp_ctx.s = NULL;
     86 	ctx->srp_ctx.B = NULL;
     87 	ctx->srp_ctx.A = NULL;
     88 	ctx->srp_ctx.a = NULL;
     89 	ctx->srp_ctx.b = NULL;
     90 	ctx->srp_ctx.v = NULL;
     91 	ctx->srp_ctx.login = NULL;
     92 	ctx->srp_ctx.info = NULL;
     93 	ctx->srp_ctx.strength = SRP_MINIMAL_N;
     94 	ctx->srp_ctx.srp_Mask = 0;
     95 	return (1);
     96 	}
     97 
     98 int SSL_SRP_CTX_free(struct ssl_st *s)
     99 	{
    100 	if (s == NULL)
    101 		return 0;
    102 	OPENSSL_free(s->srp_ctx.login);
    103 	BN_free(s->srp_ctx.N);
    104 	BN_free(s->srp_ctx.g);
    105 	BN_free(s->srp_ctx.s);
    106 	BN_free(s->srp_ctx.B);
    107 	BN_free(s->srp_ctx.A);
    108 	BN_free(s->srp_ctx.a);
    109 	BN_free(s->srp_ctx.b);
    110 	BN_free(s->srp_ctx.v);
    111 	s->srp_ctx.TLS_ext_srp_username_callback = NULL;
    112 	s->srp_ctx.SRP_cb_arg = NULL;
    113 	s->srp_ctx.SRP_verify_param_callback = NULL;
    114 	s->srp_ctx.SRP_give_srp_client_pwd_callback = NULL;
    115 	s->srp_ctx.N = NULL;
    116 	s->srp_ctx.g = NULL;
    117 	s->srp_ctx.s = NULL;
    118 	s->srp_ctx.B = NULL;
    119 	s->srp_ctx.A = NULL;
    120 	s->srp_ctx.a = NULL;
    121 	s->srp_ctx.b = NULL;
    122 	s->srp_ctx.v = NULL;
    123 	s->srp_ctx.login = NULL;
    124 	s->srp_ctx.info = NULL;
    125 	s->srp_ctx.strength = SRP_MINIMAL_N;
    126 	s->srp_ctx.srp_Mask = 0;
    127 	return (1);
    128 	}
    129 
    130 int SSL_SRP_CTX_init(struct ssl_st *s)
    131 	{
    132 	SSL_CTX *ctx;
    133 
    134 	if ((s == NULL) || ((ctx = s->ctx) == NULL))
    135 		return 0;
    136 	s->srp_ctx.SRP_cb_arg = ctx->srp_ctx.SRP_cb_arg;
    137 	/* set client Hello login callback */
    138 	s->srp_ctx.TLS_ext_srp_username_callback = ctx->srp_ctx.TLS_ext_srp_username_callback;
    139 	/* set SRP N/g param callback for verification */
    140 	s->srp_ctx.SRP_verify_param_callback = ctx->srp_ctx.SRP_verify_param_callback;
    141 	/* set SRP client passwd callback */
    142 	s->srp_ctx.SRP_give_srp_client_pwd_callback = ctx->srp_ctx.SRP_give_srp_client_pwd_callback;
    143 
    144 	s->srp_ctx.N = NULL;
    145 	s->srp_ctx.g = NULL;
    146 	s->srp_ctx.s = NULL;
    147 	s->srp_ctx.B = NULL;
    148 	s->srp_ctx.A = NULL;
    149 	s->srp_ctx.a = NULL;
    150 	s->srp_ctx.b = NULL;
    151 	s->srp_ctx.v = NULL;
    152 	s->srp_ctx.login = NULL;
    153 	s->srp_ctx.info = ctx->srp_ctx.info;
    154 	s->srp_ctx.strength = ctx->srp_ctx.strength;
    155 
    156 	if (((ctx->srp_ctx.N != NULL) &&
    157 		 ((s->srp_ctx.N = BN_dup(ctx->srp_ctx.N)) == NULL)) ||
    158 		((ctx->srp_ctx.g != NULL) &&
    159 		 ((s->srp_ctx.g = BN_dup(ctx->srp_ctx.g)) == NULL)) ||
    160 		((ctx->srp_ctx.s != NULL) &&
    161 		 ((s->srp_ctx.s = BN_dup(ctx->srp_ctx.s)) == NULL)) ||
    162 		((ctx->srp_ctx.B != NULL) &&
    163 		 ((s->srp_ctx.B = BN_dup(ctx->srp_ctx.B)) == NULL)) ||
    164 		((ctx->srp_ctx.A != NULL) &&
    165 		 ((s->srp_ctx.A = BN_dup(ctx->srp_ctx.A)) == NULL)) ||
    166 		((ctx->srp_ctx.a != NULL) &&
    167 		 ((s->srp_ctx.a = BN_dup(ctx->srp_ctx.a)) == NULL)) ||
    168 		((ctx->srp_ctx.v != NULL) &&
    169 		 ((s->srp_ctx.v = BN_dup(ctx->srp_ctx.v)) == NULL)) ||
    170 		((ctx->srp_ctx.b != NULL) &&
    171 		 ((s->srp_ctx.b = BN_dup(ctx->srp_ctx.b)) == NULL)))
    172 		{
    173 		SSLerr(SSL_F_SSL_SRP_CTX_INIT,ERR_R_BN_LIB);
    174 		goto err;
    175 		}
    176 	if ((ctx->srp_ctx.login != NULL) &&
    177 		((s->srp_ctx.login = BUF_strdup(ctx->srp_ctx.login)) == NULL))
    178 		{
    179 		SSLerr(SSL_F_SSL_SRP_CTX_INIT,ERR_R_INTERNAL_ERROR);
    180 		goto err;
    181 		}
    182 	s->srp_ctx.srp_Mask = ctx->srp_ctx.srp_Mask;
    183 
    184 	return (1);
    185 err:
    186 	OPENSSL_free(s->srp_ctx.login);
    187 	BN_free(s->srp_ctx.N);
    188 	BN_free(s->srp_ctx.g);
    189 	BN_free(s->srp_ctx.s);
    190 	BN_free(s->srp_ctx.B);
    191 	BN_free(s->srp_ctx.A);
    192 	BN_free(s->srp_ctx.a);
    193 	BN_free(s->srp_ctx.b);
    194 	BN_free(s->srp_ctx.v);
    195 	return (0);
    196 	}
    197 
    198 int SSL_CTX_SRP_CTX_init(struct ssl_ctx_st *ctx)
    199 	{
    200 	if (ctx == NULL)
    201 		return 0;
    202 
    203 	ctx->srp_ctx.SRP_cb_arg = NULL;
    204 	/* set client Hello login callback */
    205 	ctx->srp_ctx.TLS_ext_srp_username_callback = NULL;
    206 	/* set SRP N/g param callback for verification */
    207 	ctx->srp_ctx.SRP_verify_param_callback = NULL;
    208 	/* set SRP client passwd callback */
    209 	ctx->srp_ctx.SRP_give_srp_client_pwd_callback = NULL;
    210 
    211 	ctx->srp_ctx.N = NULL;
    212 	ctx->srp_ctx.g = NULL;
    213 	ctx->srp_ctx.s = NULL;
    214 	ctx->srp_ctx.B = NULL;
    215 	ctx->srp_ctx.A = NULL;
    216 	ctx->srp_ctx.a = NULL;
    217 	ctx->srp_ctx.b = NULL;
    218 	ctx->srp_ctx.v = NULL;
    219 	ctx->srp_ctx.login = NULL;
    220 	ctx->srp_ctx.srp_Mask = 0;
    221 	ctx->srp_ctx.info = NULL;
    222 	ctx->srp_ctx.strength = SRP_MINIMAL_N;
    223 
    224 	return (1);
    225 	}
    226 
    227 /* server side */
    228 int SSL_srp_server_param_with_username(SSL *s, int *ad)
    229 	{
    230 	unsigned char b[SSL_MAX_MASTER_KEY_LENGTH];
    231 	int al;
    232 
    233 	*ad = SSL_AD_UNKNOWN_PSK_IDENTITY;
    234 	if ((s->srp_ctx.TLS_ext_srp_username_callback !=NULL) &&
    235 		((al = s->srp_ctx.TLS_ext_srp_username_callback(s, ad, s->srp_ctx.SRP_cb_arg))!=SSL_ERROR_NONE))
    236 			return al;
    237 
    238 	*ad = SSL_AD_INTERNAL_ERROR;
    239 	if ((s->srp_ctx.N == NULL) ||
    240 		(s->srp_ctx.g == NULL) ||
    241 		(s->srp_ctx.s == NULL) ||
    242 		(s->srp_ctx.v == NULL))
    243 		return SSL3_AL_FATAL;
    244 
    245 	if (RAND_bytes(b, sizeof(b)) <= 0)
    246 		return SSL3_AL_FATAL;
    247 	s->srp_ctx.b = BN_bin2bn(b,sizeof(b),NULL);
    248 	OPENSSL_cleanse(b,sizeof(b));
    249 
    250 	/* Calculate:  B = (kv + g^b) % N  */
    251 
    252 	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)?
    253 			SSL_ERROR_NONE:SSL3_AL_FATAL;
    254 	}
    255 
    256 /* If the server just has the raw password, make up a verifier entry on the fly */
    257 int SSL_set_srp_server_param_pw(SSL *s, const char *user, const char *pass, const char *grp)
    258 	{
    259 	SRP_gN *GN = SRP_get_default_gN(grp);
    260 	if(GN == NULL) return -1;
    261 	s->srp_ctx.N = BN_dup(GN->N);
    262 	s->srp_ctx.g = BN_dup(GN->g);
    263 	if(s->srp_ctx.v != NULL)
    264 		{
    265 		BN_clear_free(s->srp_ctx.v);
    266 		s->srp_ctx.v = NULL;
    267 		}
    268 	if(s->srp_ctx.s != NULL)
    269 		{
    270 		BN_clear_free(s->srp_ctx.s);
    271 		s->srp_ctx.s = NULL;
    272 		}
    273 	if(!SRP_create_verifier_BN(user, pass, &s->srp_ctx.s, &s->srp_ctx.v, GN->N, GN->g)) return -1;
    274 
    275 	return 1;
    276 	}
    277 
    278 int SSL_set_srp_server_param(SSL *s, const BIGNUM *N, const BIGNUM *g,
    279 			     BIGNUM *sa, BIGNUM *v, char *info)
    280 	{
    281 	if (N!= NULL)
    282 		{
    283 		if (s->srp_ctx.N != NULL)
    284 			{
    285 			if (!BN_copy(s->srp_ctx.N,N))
    286 				{
    287 				BN_free(s->srp_ctx.N);
    288 				s->srp_ctx.N = NULL;
    289 				}
    290 			}
    291 		else
    292 			s->srp_ctx.N = BN_dup(N);
    293 		}
    294 	if (g!= NULL)
    295 		{
    296 		if (s->srp_ctx.g != NULL)
    297 			{
    298 			if (!BN_copy(s->srp_ctx.g,g))
    299 				{
    300 				BN_free(s->srp_ctx.g);
    301 				s->srp_ctx.g = NULL;
    302 				}
    303 			}
    304 		else
    305 			s->srp_ctx.g = BN_dup(g);
    306 		}
    307 	if (sa!= NULL)
    308 		{
    309 		if (s->srp_ctx.s != NULL)
    310 			{
    311 			if (!BN_copy(s->srp_ctx.s,sa))
    312 				{
    313 				BN_free(s->srp_ctx.s);
    314 				s->srp_ctx.s = NULL;
    315 				}
    316 			}
    317 		else
    318 			s->srp_ctx.s = BN_dup(sa);
    319 		}
    320 	if (v!= NULL)
    321 		{
    322 		if (s->srp_ctx.v != NULL)
    323 			{
    324 			if (!BN_copy(s->srp_ctx.v,v))
    325 				{
    326 				BN_free(s->srp_ctx.v);
    327 				s->srp_ctx.v = NULL;
    328 				}
    329 			}
    330 		else
    331 			s->srp_ctx.v = BN_dup(v);
    332 		}
    333 	s->srp_ctx.info = info;
    334 
    335 	if (!(s->srp_ctx.N) ||
    336 		!(s->srp_ctx.g) ||
    337 		!(s->srp_ctx.s) ||
    338 		!(s->srp_ctx.v))
    339 		return -1;
    340 
    341 	return 1;
    342 	}
    343 
    344 int SRP_generate_server_master_secret(SSL *s,unsigned char *master_key)
    345 	{
    346 	BIGNUM *K = NULL, *u = NULL;
    347 	int ret = -1, tmp_len;
    348 	unsigned char *tmp = NULL;
    349 
    350 	if (!SRP_Verify_A_mod_N(s->srp_ctx.A,s->srp_ctx.N))
    351 		goto err;
    352 	if (!(u = SRP_Calc_u(s->srp_ctx.A,s->srp_ctx.B,s->srp_ctx.N)))
    353 		goto err;
    354 	if (!(K = SRP_Calc_server_key(s->srp_ctx.A, s->srp_ctx.v, u, s->srp_ctx.b, s->srp_ctx.N)))
    355 		goto err;
    356 
    357 	tmp_len = BN_num_bytes(K);
    358 	if ((tmp = OPENSSL_malloc(tmp_len)) == NULL)
    359 		goto err;
    360 	BN_bn2bin(K, tmp);
    361 	ret = s->method->ssl3_enc->generate_master_secret(s,master_key,tmp,tmp_len);
    362 err:
    363 	if (tmp)
    364 		{
    365 		OPENSSL_cleanse(tmp,tmp_len) ;
    366 		OPENSSL_free(tmp);
    367 		}
    368 	BN_clear_free(K);
    369 	BN_clear_free(u);
    370 	return ret;
    371 	}
    372 
    373 /* client side */
    374 int SRP_generate_client_master_secret(SSL *s,unsigned char *master_key)
    375 	{
    376 	BIGNUM *x = NULL, *u = NULL, *K = NULL;
    377 	int ret = -1, tmp_len;
    378 	char *passwd = NULL;
    379 	unsigned char *tmp = NULL;
    380 
    381 	/* Checks if b % n == 0
    382 	 */
    383 	if (SRP_Verify_B_mod_N(s->srp_ctx.B,s->srp_ctx.N)==0) goto err;
    384 	if (!(u = SRP_Calc_u(s->srp_ctx.A,s->srp_ctx.B,s->srp_ctx.N))) goto err;
    385 	if (s->srp_ctx.SRP_give_srp_client_pwd_callback == NULL) goto err;
    386 	if (!(passwd = s->srp_ctx.SRP_give_srp_client_pwd_callback(s, s->srp_ctx.SRP_cb_arg))) goto err;
    387 	if (!(x = SRP_Calc_x(s->srp_ctx.s,s->srp_ctx.login,passwd))) goto err;
    388 	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;
    389 
    390 	tmp_len = BN_num_bytes(K);
    391 	if ((tmp = OPENSSL_malloc(tmp_len)) == NULL) goto err;
    392 	BN_bn2bin(K, tmp);
    393 	ret = s->method->ssl3_enc->generate_master_secret(s,master_key,tmp,tmp_len);
    394 err:
    395 	if (tmp)
    396 		{
    397 		OPENSSL_cleanse(tmp,tmp_len) ;
    398 		OPENSSL_free(tmp);
    399 		}
    400 	BN_clear_free(K);
    401 	BN_clear_free(x);
    402 	if (passwd)
    403 		{
    404 		OPENSSL_cleanse(passwd,strlen(passwd)) ;
    405 		OPENSSL_free(passwd);
    406 		}
    407 	BN_clear_free(u);
    408 	return ret;
    409 	}
    410 
    411 int SRP_Calc_A_param(SSL *s)
    412 	{
    413 	unsigned char rnd[SSL_MAX_MASTER_KEY_LENGTH];
    414 
    415 	if (BN_num_bits(s->srp_ctx.N) < s->srp_ctx.strength)
    416 		return -1;
    417 
    418 	if (s->srp_ctx.SRP_verify_param_callback ==NULL &&
    419 		!SRP_check_known_gN_param(s->srp_ctx.g,s->srp_ctx.N))
    420 		return -1 ;
    421 
    422 	RAND_bytes(rnd, sizeof(rnd));
    423 	s->srp_ctx.a = BN_bin2bn(rnd, sizeof(rnd), s->srp_ctx.a);
    424 	OPENSSL_cleanse(rnd, sizeof(rnd));
    425 
    426 	if (!(s->srp_ctx.A = SRP_Calc_A(s->srp_ctx.a,s->srp_ctx.N,s->srp_ctx.g)))
    427 		return -1;
    428 
    429 	/* We can have a callback to verify SRP param!! */
    430 	if (s->srp_ctx.SRP_verify_param_callback !=NULL)
    431 		return s->srp_ctx.SRP_verify_param_callback(s,s->srp_ctx.SRP_cb_arg);
    432 
    433 	return 1;
    434 	}
    435 
    436 BIGNUM *SSL_get_srp_g(SSL *s)
    437 	{
    438 	if (s->srp_ctx.g != NULL)
    439 		return s->srp_ctx.g;
    440 	return s->ctx->srp_ctx.g;
    441 	}
    442 
    443 BIGNUM *SSL_get_srp_N(SSL *s)
    444 	{
    445 	if (s->srp_ctx.N != NULL)
    446 		return s->srp_ctx.N;
    447 	return s->ctx->srp_ctx.N;
    448 	}
    449 
    450 char *SSL_get_srp_username(SSL *s)
    451 	{
    452 	if (s->srp_ctx.login != NULL)
    453 		return s->srp_ctx.login;
    454 	return s->ctx->srp_ctx.login;
    455 	}
    456 
    457 char *SSL_get_srp_userinfo(SSL *s)
    458 	{
    459 	if (s->srp_ctx.info != NULL)
    460 		return s->srp_ctx.info;
    461 	return s->ctx->srp_ctx.info;
    462 	}
    463 
    464 #define tls1_ctx_ctrl ssl3_ctx_ctrl
    465 #define tls1_ctx_callback_ctrl ssl3_ctx_callback_ctrl
    466 
    467 int SSL_CTX_set_srp_username(SSL_CTX *ctx,char *name)
    468 	{
    469 	return tls1_ctx_ctrl(ctx,SSL_CTRL_SET_TLS_EXT_SRP_USERNAME,0,name);
    470 	}
    471 
    472 int SSL_CTX_set_srp_password(SSL_CTX *ctx,char *password)
    473 	{
    474 	return tls1_ctx_ctrl(ctx,SSL_CTRL_SET_TLS_EXT_SRP_PASSWORD,0,password);
    475 	}
    476 
    477 int SSL_CTX_set_srp_strength(SSL_CTX *ctx, int strength)
    478 	{
    479 	return tls1_ctx_ctrl(ctx, SSL_CTRL_SET_TLS_EXT_SRP_STRENGTH, strength,
    480 			     NULL);
    481 	}
    482 
    483 int SSL_CTX_set_srp_verify_param_callback(SSL_CTX *ctx, int (*cb)(SSL *,void *))
    484 	{
    485 	return tls1_ctx_callback_ctrl(ctx,SSL_CTRL_SET_SRP_VERIFY_PARAM_CB,
    486 				      (void (*)(void))cb);
    487 	}
    488 
    489 int SSL_CTX_set_srp_cb_arg(SSL_CTX *ctx, void *arg)
    490 	{
    491 	return tls1_ctx_ctrl(ctx,SSL_CTRL_SET_SRP_ARG,0,arg);
    492 	}
    493 
    494 int SSL_CTX_set_srp_username_callback(SSL_CTX *ctx,
    495 				      int (*cb)(SSL *,int *,void *))
    496 	{
    497 	return tls1_ctx_callback_ctrl(ctx,SSL_CTRL_SET_TLS_EXT_SRP_USERNAME_CB,
    498 				      (void (*)(void))cb);
    499 	}
    500 
    501 int SSL_CTX_set_srp_client_pwd_callback(SSL_CTX *ctx, char *(*cb)(SSL *,void *))
    502 	{
    503 	return tls1_ctx_callback_ctrl(ctx,SSL_CTRL_SET_SRP_GIVE_CLIENT_PWD_CB,
    504 				      (void (*)(void))cb);
    505 	}
    506 
    507 #endif
    508