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      1 /* ssl/s23_clnt.c */
      2 /* Copyright (C) 1995-1998 Eric Young (eay (at) cryptsoft.com)
      3  * All rights reserved.
      4  *
      5  * This package is an SSL implementation written
      6  * by Eric Young (eay (at) 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 (at) 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 (at) 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 (at) 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  * Copyright (c) 1998-2006 The OpenSSL Project.  All rights reserved.
     60  *
     61  * Redistribution and use in source and binary forms, with or without
     62  * modification, are permitted provided that the following conditions
     63  * are met:
     64  *
     65  * 1. Redistributions of source code must retain the above copyright
     66  *    notice, this list of conditions and the following disclaimer.
     67  *
     68  * 2. Redistributions in binary form must reproduce the above copyright
     69  *    notice, this list of conditions and the following disclaimer in
     70  *    the documentation and/or other materials provided with the
     71  *    distribution.
     72  *
     73  * 3. All advertising materials mentioning features or use of this
     74  *    software must display the following acknowledgment:
     75  *    "This product includes software developed by the OpenSSL Project
     76  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
     77  *
     78  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
     79  *    endorse or promote products derived from this software without
     80  *    prior written permission. For written permission, please contact
     81  *    openssl-core (at) openssl.org.
     82  *
     83  * 5. Products derived from this software may not be called "OpenSSL"
     84  *    nor may "OpenSSL" appear in their names without prior written
     85  *    permission of the OpenSSL Project.
     86  *
     87  * 6. Redistributions of any form whatsoever must retain the following
     88  *    acknowledgment:
     89  *    "This product includes software developed by the OpenSSL Project
     90  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
     91  *
     92  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
     93  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     94  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     95  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
     96  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     97  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     98  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
     99  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
    100  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
    101  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
    102  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
    103  * OF THE POSSIBILITY OF SUCH DAMAGE.
    104  * ====================================================================
    105  *
    106  * This product includes cryptographic software written by Eric Young
    107  * (eay (at) cryptsoft.com).  This product includes software written by Tim
    108  * Hudson (tjh (at) cryptsoft.com).
    109  *
    110  */
    111 
    112 #include <stdio.h>
    113 #include "ssl_locl.h"
    114 #include <openssl/buffer.h>
    115 #include <openssl/rand.h>
    116 #include <openssl/objects.h>
    117 #include <openssl/evp.h>
    118 
    119 static const SSL_METHOD *ssl23_get_client_method(int ver);
    120 static int ssl23_client_hello(SSL *s);
    121 static int ssl23_get_server_hello(SSL *s);
    122 static const SSL_METHOD *ssl23_get_client_method(int ver)
    123 	{
    124 #ifndef OPENSSL_NO_SSL2
    125 	if (ver == SSL2_VERSION)
    126 		return(SSLv2_client_method());
    127 #endif
    128 	if (ver == SSL3_VERSION)
    129 		return(SSLv3_client_method());
    130 	else if (ver == TLS1_VERSION)
    131 		return(TLSv1_client_method());
    132 	else if (ver == TLS1_1_VERSION)
    133 		return(TLSv1_1_client_method());
    134 	else if (ver == TLS1_2_VERSION)
    135 		return(TLSv1_2_client_method());
    136 	else
    137 		return(NULL);
    138 	}
    139 
    140 IMPLEMENT_ssl23_meth_func(SSLv23_client_method,
    141 			ssl_undefined_function,
    142 			ssl23_connect,
    143 			ssl23_get_client_method)
    144 
    145 int ssl23_connect(SSL *s)
    146 	{
    147 	BUF_MEM *buf=NULL;
    148 	unsigned long Time=(unsigned long)time(NULL);
    149 	void (*cb)(const SSL *ssl,int type,int val)=NULL;
    150 	int ret= -1;
    151 	int new_state,state;
    152 
    153 	RAND_add(&Time,sizeof(Time),0);
    154 	ERR_clear_error();
    155 	clear_sys_error();
    156 
    157 	if (s->info_callback != NULL)
    158 		cb=s->info_callback;
    159 	else if (s->ctx->info_callback != NULL)
    160 		cb=s->ctx->info_callback;
    161 
    162 	s->in_handshake++;
    163 	if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s);
    164 
    165 	for (;;)
    166 		{
    167 		state=s->state;
    168 
    169 		switch(s->state)
    170 			{
    171 		case SSL_ST_BEFORE:
    172 		case SSL_ST_CONNECT:
    173 		case SSL_ST_BEFORE|SSL_ST_CONNECT:
    174 		case SSL_ST_OK|SSL_ST_CONNECT:
    175 
    176 			if (s->session != NULL)
    177 				{
    178 				SSLerr(SSL_F_SSL23_CONNECT,SSL_R_SSL23_DOING_SESSION_ID_REUSE);
    179 				ret= -1;
    180 				goto end;
    181 				}
    182 			s->server=0;
    183 			if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
    184 
    185 			/* s->version=TLS1_VERSION; */
    186 			s->type=SSL_ST_CONNECT;
    187 
    188 			if (s->init_buf == NULL)
    189 				{
    190 				if ((buf=BUF_MEM_new()) == NULL)
    191 					{
    192 					ret= -1;
    193 					goto end;
    194 					}
    195 				if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH))
    196 					{
    197 					ret= -1;
    198 					goto end;
    199 					}
    200 				s->init_buf=buf;
    201 				buf=NULL;
    202 				}
    203 
    204 			if (!ssl3_setup_buffers(s)) { ret= -1; goto end; }
    205 
    206 			ssl3_init_finished_mac(s);
    207 
    208 			s->state=SSL23_ST_CW_CLNT_HELLO_A;
    209 			s->ctx->stats.sess_connect++;
    210 			s->init_num=0;
    211 			break;
    212 
    213 		case SSL23_ST_CW_CLNT_HELLO_A:
    214 		case SSL23_ST_CW_CLNT_HELLO_B:
    215 
    216 			s->shutdown=0;
    217 			ret=ssl23_client_hello(s);
    218 			if (ret <= 0) goto end;
    219 			s->state=SSL23_ST_CR_SRVR_HELLO_A;
    220 			s->init_num=0;
    221 
    222 			break;
    223 
    224 		case SSL23_ST_CR_SRVR_HELLO_A:
    225 		case SSL23_ST_CR_SRVR_HELLO_B:
    226 			ret=ssl23_get_server_hello(s);
    227 			if (ret >= 0) cb=NULL;
    228 			goto end;
    229 			/* break; */
    230 
    231 		default:
    232 			SSLerr(SSL_F_SSL23_CONNECT,SSL_R_UNKNOWN_STATE);
    233 			ret= -1;
    234 			goto end;
    235 			/* break; */
    236 			}
    237 
    238 		if (s->debug) { (void)BIO_flush(s->wbio); }
    239 
    240 		if ((cb != NULL) && (s->state != state))
    241 			{
    242 			new_state=s->state;
    243 			s->state=state;
    244 			cb(s,SSL_CB_CONNECT_LOOP,1);
    245 			s->state=new_state;
    246 			}
    247 		}
    248 end:
    249 	s->in_handshake--;
    250 	if (buf != NULL)
    251 		BUF_MEM_free(buf);
    252 	if (cb != NULL)
    253 		cb(s,SSL_CB_CONNECT_EXIT,ret);
    254 	return(ret);
    255 	}
    256 
    257 static int ssl23_no_ssl2_ciphers(SSL *s)
    258 	{
    259 	SSL_CIPHER *cipher;
    260 	STACK_OF(SSL_CIPHER) *ciphers;
    261 	int i;
    262 	ciphers = SSL_get_ciphers(s);
    263 	for (i = 0; i < sk_SSL_CIPHER_num(ciphers); i++)
    264 		{
    265 		cipher = sk_SSL_CIPHER_value(ciphers, i);
    266 		if (cipher->algorithm_ssl == SSL_SSLV2)
    267 			return 0;
    268 		}
    269 	return 1;
    270 	}
    271 
    272 static int ssl23_client_hello(SSL *s)
    273 	{
    274 	unsigned char *buf;
    275 	unsigned char *p,*d;
    276 	int i,ch_len;
    277 	unsigned long Time,l;
    278 	int ssl2_compat;
    279 	int version = 0, version_major, version_minor;
    280 #ifndef OPENSSL_NO_COMP
    281 	int j;
    282 	SSL_COMP *comp;
    283 #endif
    284 	int ret;
    285 	unsigned long mask, options = s->options;
    286 
    287 	ssl2_compat = (options & SSL_OP_NO_SSLv2) ? 0 : 1;
    288 
    289 	if (ssl2_compat && ssl23_no_ssl2_ciphers(s))
    290 		ssl2_compat = 0;
    291 
    292 	/*
    293 	 * SSL_OP_NO_X disables all protocols above X *if* there are
    294 	 * some protocols below X enabled. This is required in order
    295 	 * to maintain "version capability" vector contiguous. So
    296 	 * that if application wants to disable TLS1.0 in favour of
    297 	 * TLS1>=1, it would be insufficient to pass SSL_NO_TLSv1, the
    298 	 * answer is SSL_OP_NO_TLSv1|SSL_OP_NO_SSLv3|SSL_OP_NO_SSLv2.
    299 	 */
    300 	mask =	SSL_OP_NO_TLSv1_1|SSL_OP_NO_TLSv1
    301 #if !defined(OPENSSL_NO_SSL3)
    302 		|SSL_OP_NO_SSLv3
    303 #endif
    304 #if !defined(OPENSSL_NO_SSL2)
    305 		|(ssl2_compat?SSL_OP_NO_SSLv2:0)
    306 #endif
    307 		;
    308 #if !defined(OPENSSL_NO_TLS1_2_CLIENT)
    309 	version = TLS1_2_VERSION;
    310 
    311 	if ((options & SSL_OP_NO_TLSv1_2) && (options & mask) != mask)
    312 		version = TLS1_1_VERSION;
    313 #else
    314 	version = TLS1_1_VERSION;
    315 #endif
    316 	mask &= ~SSL_OP_NO_TLSv1_1;
    317 	if ((options & SSL_OP_NO_TLSv1_1) && (options & mask) != mask)
    318 		version = TLS1_VERSION;
    319 	mask &= ~SSL_OP_NO_TLSv1;
    320 #if !defined(OPENSSL_NO_SSL3)
    321 	if ((options & SSL_OP_NO_TLSv1) && (options & mask) != mask)
    322 		version = SSL3_VERSION;
    323 	mask &= ~SSL_OP_NO_SSLv3;
    324 #endif
    325 #if !defined(OPENSSL_NO_SSL2)
    326 	if ((options & SSL_OP_NO_SSLv3) && (options & mask) != mask)
    327 		version = SSL2_VERSION;
    328 #endif
    329 
    330 #ifndef OPENSSL_NO_TLSEXT
    331 	if (version != SSL2_VERSION)
    332 		{
    333 		/* have to disable SSL 2.0 compatibility if we need TLS extensions */
    334 
    335 		if (s->tlsext_hostname != NULL)
    336 			ssl2_compat = 0;
    337 		if (s->tlsext_status_type != -1)
    338 			ssl2_compat = 0;
    339 #ifdef TLSEXT_TYPE_opaque_prf_input
    340 		if (s->ctx->tlsext_opaque_prf_input_callback != 0 || s->tlsext_opaque_prf_input != NULL)
    341 			ssl2_compat = 0;
    342 #endif
    343 		}
    344 #endif
    345 
    346 	buf=(unsigned char *)s->init_buf->data;
    347 	if (s->state == SSL23_ST_CW_CLNT_HELLO_A)
    348 		{
    349 #if 0
    350 		/* don't reuse session-id's */
    351 		if (!ssl_get_new_session(s,0))
    352 			{
    353 			return(-1);
    354 			}
    355 #endif
    356 
    357 		p=s->s3->client_random;
    358 		Time=(unsigned long)time(NULL);		/* Time */
    359 		l2n(Time,p);
    360 		if (RAND_pseudo_bytes(p,SSL3_RANDOM_SIZE-4) <= 0)
    361 			return -1;
    362 
    363 		if (version == TLS1_2_VERSION)
    364 			{
    365 			version_major = TLS1_2_VERSION_MAJOR;
    366 			version_minor = TLS1_2_VERSION_MINOR;
    367 			}
    368 		else if (version == TLS1_1_VERSION)
    369 			{
    370 			version_major = TLS1_1_VERSION_MAJOR;
    371 			version_minor = TLS1_1_VERSION_MINOR;
    372 			}
    373 		else if (version == TLS1_VERSION)
    374 			{
    375 			version_major = TLS1_VERSION_MAJOR;
    376 			version_minor = TLS1_VERSION_MINOR;
    377 			}
    378 #ifdef OPENSSL_FIPS
    379 		else if(FIPS_mode())
    380 			{
    381 			SSLerr(SSL_F_SSL23_CLIENT_HELLO,
    382 					SSL_R_ONLY_TLS_ALLOWED_IN_FIPS_MODE);
    383 			return -1;
    384 			}
    385 #endif
    386 		else if (version == SSL3_VERSION)
    387 			{
    388 			version_major = SSL3_VERSION_MAJOR;
    389 			version_minor = SSL3_VERSION_MINOR;
    390 			}
    391 		else if (version == SSL2_VERSION)
    392 			{
    393 			version_major = SSL2_VERSION_MAJOR;
    394 			version_minor = SSL2_VERSION_MINOR;
    395 			}
    396 		else
    397 			{
    398 			SSLerr(SSL_F_SSL23_CLIENT_HELLO,SSL_R_NO_PROTOCOLS_AVAILABLE);
    399 			return(-1);
    400 			}
    401 
    402 		s->client_version = version;
    403 
    404 		if (ssl2_compat)
    405 			{
    406 			/* create SSL 2.0 compatible Client Hello */
    407 
    408 			/* two byte record header will be written last */
    409 			d = &(buf[2]);
    410 			p = d + 9; /* leave space for message type, version, individual length fields */
    411 
    412 			*(d++) = SSL2_MT_CLIENT_HELLO;
    413 			*(d++) = version_major;
    414 			*(d++) = version_minor;
    415 
    416 			/* Ciphers supported */
    417 			i=ssl_cipher_list_to_bytes(s,SSL_get_ciphers(s),p,0);
    418 			if (i == 0)
    419 				{
    420 				/* no ciphers */
    421 				SSLerr(SSL_F_SSL23_CLIENT_HELLO,SSL_R_NO_CIPHERS_AVAILABLE);
    422 				return -1;
    423 				}
    424 			s2n(i,d);
    425 			p+=i;
    426 
    427 			/* put in the session-id length (zero since there is no reuse) */
    428 #if 0
    429 			s->session->session_id_length=0;
    430 #endif
    431 			s2n(0,d);
    432 
    433 			if (s->options & SSL_OP_NETSCAPE_CHALLENGE_BUG)
    434 				ch_len=SSL2_CHALLENGE_LENGTH;
    435 			else
    436 				ch_len=SSL2_MAX_CHALLENGE_LENGTH;
    437 
    438 			/* write out sslv2 challenge */
    439 			/* Note that ch_len must be <= SSL3_RANDOM_SIZE (32),
    440 			   because it is one of SSL2_MAX_CHALLENGE_LENGTH (32)
    441 			   or SSL2_MAX_CHALLENGE_LENGTH (16), but leave the
    442 			   check in for futurproofing */
    443 			if (SSL3_RANDOM_SIZE < ch_len)
    444 				i=SSL3_RANDOM_SIZE;
    445 			else
    446 				i=ch_len;
    447 			s2n(i,d);
    448 			memset(&(s->s3->client_random[0]),0,SSL3_RANDOM_SIZE);
    449 			if (RAND_pseudo_bytes(&(s->s3->client_random[SSL3_RANDOM_SIZE-i]),i) <= 0)
    450 				return -1;
    451 
    452 			memcpy(p,&(s->s3->client_random[SSL3_RANDOM_SIZE-i]),i);
    453 			p+=i;
    454 
    455 			i= p- &(buf[2]);
    456 			buf[0]=((i>>8)&0xff)|0x80;
    457 			buf[1]=(i&0xff);
    458 
    459 			/* number of bytes to write */
    460 			s->init_num=i+2;
    461 			s->init_off=0;
    462 
    463 			ssl3_finish_mac(s,&(buf[2]),i);
    464 			}
    465 		else
    466 			{
    467 			/* create Client Hello in SSL 3.0/TLS 1.0 format */
    468 
    469 			/* do the record header (5 bytes) and handshake message header (4 bytes) last */
    470 			d = p = &(buf[9]);
    471 
    472 			*(p++) = version_major;
    473 			*(p++) = version_minor;
    474 
    475 			/* Random stuff */
    476 			memcpy(p, s->s3->client_random, SSL3_RANDOM_SIZE);
    477 			p += SSL3_RANDOM_SIZE;
    478 
    479 			/* Session ID (zero since there is no reuse) */
    480 			*(p++) = 0;
    481 
    482 			/* Ciphers supported (using SSL 3.0/TLS 1.0 format) */
    483 			i=ssl_cipher_list_to_bytes(s,SSL_get_ciphers(s),&(p[2]),ssl3_put_cipher_by_char);
    484 			if (i == 0)
    485 				{
    486 				SSLerr(SSL_F_SSL23_CLIENT_HELLO,SSL_R_NO_CIPHERS_AVAILABLE);
    487 				return -1;
    488 				}
    489 #ifdef OPENSSL_MAX_TLS1_2_CIPHER_LENGTH
    490 			/* Some servers hang if client hello > 256 bytes
    491 			 * as hack workaround chop number of supported ciphers
    492 			 * to keep it well below this if we use TLS v1.2
    493 			 */
    494 			if (TLS1_get_version(s) >= TLS1_2_VERSION
    495 				&& i > OPENSSL_MAX_TLS1_2_CIPHER_LENGTH)
    496 				i = OPENSSL_MAX_TLS1_2_CIPHER_LENGTH & ~1;
    497 #endif
    498 			s2n(i,p);
    499 			p+=i;
    500 
    501 			/* COMPRESSION */
    502 #ifdef OPENSSL_NO_COMP
    503 			*(p++)=1;
    504 #else
    505 			if ((s->options & SSL_OP_NO_COMPRESSION)
    506 						|| !s->ctx->comp_methods)
    507 				j=0;
    508 			else
    509 				j=sk_SSL_COMP_num(s->ctx->comp_methods);
    510 			*(p++)=1+j;
    511 			for (i=0; i<j; i++)
    512 				{
    513 				comp=sk_SSL_COMP_value(s->ctx->comp_methods,i);
    514 				*(p++)=comp->id;
    515 				}
    516 #endif
    517 			*(p++)=0; /* Add the NULL method */
    518 
    519 #ifndef OPENSSL_NO_TLSEXT
    520 			/* TLS extensions*/
    521 			if (ssl_prepare_clienthello_tlsext(s) <= 0)
    522 				{
    523 				SSLerr(SSL_F_SSL23_CLIENT_HELLO,SSL_R_CLIENTHELLO_TLSEXT);
    524 				return -1;
    525 				}
    526 			if ((p = ssl_add_clienthello_tlsext(s, p, buf+SSL3_RT_MAX_PLAIN_LENGTH)) == NULL)
    527 				{
    528 				SSLerr(SSL_F_SSL23_CLIENT_HELLO,ERR_R_INTERNAL_ERROR);
    529 				return -1;
    530 				}
    531 #endif
    532 
    533 			l = p-d;
    534 
    535 			/* fill in 4-byte handshake header */
    536 			d=&(buf[5]);
    537 			*(d++)=SSL3_MT_CLIENT_HELLO;
    538 			l2n3(l,d);
    539 
    540 			l += 4;
    541 
    542 			if (l > SSL3_RT_MAX_PLAIN_LENGTH)
    543 				{
    544 				SSLerr(SSL_F_SSL23_CLIENT_HELLO,ERR_R_INTERNAL_ERROR);
    545 				return -1;
    546 				}
    547 
    548 			/* fill in 5-byte record header */
    549 			d=buf;
    550 			*(d++) = SSL3_RT_HANDSHAKE;
    551 			*(d++) = version_major;
    552 			/* Some servers hang if we use long client hellos
    553 			 * and a record number > TLS 1.0.
    554 			 */
    555 			if (TLS1_get_client_version(s) > TLS1_VERSION)
    556 				*(d++) = 1;
    557 			else
    558 				*(d++) = version_minor;
    559 			s2n((int)l,d);
    560 
    561 			/* number of bytes to write */
    562 			s->init_num=p-buf;
    563 			s->init_off=0;
    564 
    565 			ssl3_finish_mac(s,&(buf[5]), s->init_num - 5);
    566 			}
    567 
    568 		s->state=SSL23_ST_CW_CLNT_HELLO_B;
    569 		s->init_off=0;
    570 		}
    571 
    572 	/* SSL3_ST_CW_CLNT_HELLO_B */
    573 	ret = ssl23_write_bytes(s);
    574 
    575 	if ((ret >= 2) && s->msg_callback)
    576 		{
    577 		/* Client Hello has been sent; tell msg_callback */
    578 
    579 		if (ssl2_compat)
    580 			s->msg_callback(1, SSL2_VERSION, 0, s->init_buf->data+2, ret-2, s, s->msg_callback_arg);
    581 		else
    582 			s->msg_callback(1, version, SSL3_RT_HANDSHAKE, s->init_buf->data+5, ret-5, s, s->msg_callback_arg);
    583 		}
    584 
    585 	return ret;
    586 	}
    587 
    588 static int ssl23_get_server_hello(SSL *s)
    589 	{
    590 	char buf[8];
    591 	unsigned char *p;
    592 	int i;
    593 	int n;
    594 
    595 	n=ssl23_read_bytes(s,7);
    596 
    597 	if (n != 7) return(n);
    598 	p=s->packet;
    599 
    600 	memcpy(buf,p,n);
    601 
    602 	if ((p[0] & 0x80) && (p[2] == SSL2_MT_SERVER_HELLO) &&
    603 		(p[5] == 0x00) && (p[6] == 0x02))
    604 		{
    605 #ifdef OPENSSL_NO_SSL2
    606 		SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_R_UNSUPPORTED_PROTOCOL);
    607 		goto err;
    608 #else
    609 		/* we are talking sslv2 */
    610 		/* we need to clean up the SSLv3 setup and put in the
    611 		 * sslv2 stuff. */
    612 		int ch_len;
    613 
    614 		if (s->options & SSL_OP_NO_SSLv2)
    615 			{
    616 			SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_R_UNSUPPORTED_PROTOCOL);
    617 			goto err;
    618 			}
    619 		if (s->s2 == NULL)
    620 			{
    621 			if (!ssl2_new(s))
    622 				goto err;
    623 			}
    624 		else
    625 			ssl2_clear(s);
    626 
    627 		if (s->options & SSL_OP_NETSCAPE_CHALLENGE_BUG)
    628 			ch_len=SSL2_CHALLENGE_LENGTH;
    629 		else
    630 			ch_len=SSL2_MAX_CHALLENGE_LENGTH;
    631 
    632 		/* write out sslv2 challenge */
    633 		/* Note that ch_len must be <= SSL3_RANDOM_SIZE (32), because
    634 		   it is one of SSL2_MAX_CHALLENGE_LENGTH (32) or
    635 		   SSL2_MAX_CHALLENGE_LENGTH (16), but leave the check in for
    636 		   futurproofing */
    637 		i=(SSL3_RANDOM_SIZE < ch_len)
    638 			?SSL3_RANDOM_SIZE:ch_len;
    639 		s->s2->challenge_length=i;
    640 		memcpy(s->s2->challenge,
    641 			&(s->s3->client_random[SSL3_RANDOM_SIZE-i]),i);
    642 
    643 		if (s->s3 != NULL) ssl3_free(s);
    644 
    645 		if (!BUF_MEM_grow_clean(s->init_buf,
    646 			SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER))
    647 			{
    648 			SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,ERR_R_BUF_LIB);
    649 			goto err;
    650 			}
    651 
    652 		s->state=SSL2_ST_GET_SERVER_HELLO_A;
    653 		if (!(s->client_version == SSL2_VERSION))
    654 			/* use special padding (SSL 3.0 draft/RFC 2246, App. E.2) */
    655 			s->s2->ssl2_rollback=1;
    656 
    657 		/* setup the 7 bytes we have read so we get them from
    658 		 * the sslv2 buffer */
    659 		s->rstate=SSL_ST_READ_HEADER;
    660 		s->packet_length=n;
    661 		s->packet= &(s->s2->rbuf[0]);
    662 		memcpy(s->packet,buf,n);
    663 		s->s2->rbuf_left=n;
    664 		s->s2->rbuf_offs=0;
    665 
    666 		/* we have already written one */
    667 		s->s2->write_sequence=1;
    668 
    669 		s->method=SSLv2_client_method();
    670 		s->handshake_func=s->method->ssl_connect;
    671 #endif
    672 		}
    673 	else if (p[1] == SSL3_VERSION_MAJOR &&
    674 	         p[2] <= TLS1_2_VERSION_MINOR &&
    675 	         ((p[0] == SSL3_RT_HANDSHAKE && p[5] == SSL3_MT_SERVER_HELLO) ||
    676 	          (p[0] == SSL3_RT_ALERT && p[3] == 0 && p[4] == 2)))
    677 		{
    678 		/* we have sslv3 or tls1 (server hello or alert) */
    679 
    680 		if ((p[2] == SSL3_VERSION_MINOR) &&
    681 			!(s->options & SSL_OP_NO_SSLv3))
    682 			{
    683 #ifdef OPENSSL_FIPS
    684 			if(FIPS_mode())
    685 				{
    686 				SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,
    687 					SSL_R_ONLY_TLS_ALLOWED_IN_FIPS_MODE);
    688 				goto err;
    689 				}
    690 #endif
    691 			s->version=SSL3_VERSION;
    692 			s->method=SSLv3_client_method();
    693 			}
    694 		else if ((p[2] == TLS1_VERSION_MINOR) &&
    695 			!(s->options & SSL_OP_NO_TLSv1))
    696 			{
    697 			s->version=TLS1_VERSION;
    698 			s->method=TLSv1_client_method();
    699 			}
    700 		else if ((p[2] == TLS1_1_VERSION_MINOR) &&
    701 			!(s->options & SSL_OP_NO_TLSv1_1))
    702 			{
    703 			s->version=TLS1_1_VERSION;
    704 			s->method=TLSv1_1_client_method();
    705 			}
    706 		else if ((p[2] == TLS1_2_VERSION_MINOR) &&
    707 			!(s->options & SSL_OP_NO_TLSv1_2))
    708 			{
    709 			s->version=TLS1_2_VERSION;
    710 			s->method=TLSv1_2_client_method();
    711 			}
    712 		else
    713 			{
    714 			SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_R_UNSUPPORTED_PROTOCOL);
    715 			goto err;
    716 			}
    717 
    718 		if (p[0] == SSL3_RT_ALERT && p[5] != SSL3_AL_WARNING)
    719 			{
    720 			/* fatal alert */
    721 
    722 			void (*cb)(const SSL *ssl,int type,int val)=NULL;
    723 			int j;
    724 
    725 			if (s->info_callback != NULL)
    726 				cb=s->info_callback;
    727 			else if (s->ctx->info_callback != NULL)
    728 				cb=s->ctx->info_callback;
    729 
    730 			i=p[5];
    731 			if (cb != NULL)
    732 				{
    733 				j=(i<<8)|p[6];
    734 				cb(s,SSL_CB_READ_ALERT,j);
    735 				}
    736 
    737 			if (s->msg_callback)
    738 				s->msg_callback(0, s->version, SSL3_RT_ALERT, p+5, 2, s, s->msg_callback_arg);
    739 
    740 			s->rwstate=SSL_NOTHING;
    741 			SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_AD_REASON_OFFSET+p[6]);
    742 			goto err;
    743 			}
    744 
    745 		if (!ssl_init_wbio_buffer(s,1)) goto err;
    746 
    747 		/* we are in this state */
    748 		s->state=SSL3_ST_CR_SRVR_HELLO_A;
    749 
    750 		/* put the 7 bytes we have read into the input buffer
    751 		 * for SSLv3 */
    752 		s->rstate=SSL_ST_READ_HEADER;
    753 		s->packet_length=n;
    754 		if (s->s3->rbuf.buf == NULL)
    755 			if (!ssl3_setup_read_buffer(s))
    756 				goto err;
    757 		s->packet= &(s->s3->rbuf.buf[0]);
    758 		memcpy(s->packet,buf,n);
    759 		s->s3->rbuf.left=n;
    760 		s->s3->rbuf.offset=0;
    761 
    762 		s->handshake_func=s->method->ssl_connect;
    763 		}
    764 	else
    765 		{
    766 		SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_R_UNKNOWN_PROTOCOL);
    767 		goto err;
    768 		}
    769 	s->init_num=0;
    770 
    771 	/* Since, if we are sending a ssl23 client hello, we are not
    772 	 * reusing a session-id */
    773         if (!s->session_creation_enabled)
    774 		{
    775 		if (!(s->client_version == SSL2_VERSION))
    776 			ssl3_send_alert(s,SSL3_AL_FATAL,SSL_AD_HANDSHAKE_FAILURE);
    777 		SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_R_SESSION_MAY_NOT_BE_CREATED);
    778 		goto err;
    779 		}
    780 	if (!ssl_get_new_session(s,0))
    781 		goto err;
    782 
    783 	return(SSL_connect(s));
    784 err:
    785 	return(-1);
    786 	}
    787