s23_clnt.c revision 264331
1/* ssl/s23_clnt.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 * 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@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@cryptsoft.com).  This product includes software written by Tim
108 * Hudson (tjh@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
119static const SSL_METHOD *ssl23_get_client_method(int ver);
120static int ssl23_client_hello(SSL *s);
121static int ssl23_get_server_hello(SSL *s);
122static 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
140IMPLEMENT_ssl23_meth_func(SSLv23_client_method,
141			ssl_undefined_function,
142			ssl23_connect,
143			ssl23_get_client_method)
144
145int 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		}
248end:
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
257static 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/* Fill a ClientRandom or ServerRandom field of length len. Returns <= 0
273 * on failure, 1 on success. */
274int ssl_fill_hello_random(SSL *s, int server, unsigned char *result, int len)
275	{
276	int send_time = 0;
277
278	if (len < 4)
279		return 0;
280	if (server)
281		send_time = (s->mode & SSL_MODE_SEND_SERVERHELLO_TIME) != 0;
282	else
283		send_time = (s->mode & SSL_MODE_SEND_CLIENTHELLO_TIME) != 0;
284	if (send_time)
285		{
286		unsigned long Time = (unsigned long)time(NULL);
287		unsigned char *p = result;
288		l2n(Time, p);
289		return RAND_pseudo_bytes(p, len-4);
290		}
291	else
292		return RAND_pseudo_bytes(result, len);
293	}
294
295static int ssl23_client_hello(SSL *s)
296	{
297	unsigned char *buf;
298	unsigned char *p,*d;
299	int i,ch_len;
300	unsigned long l;
301	int ssl2_compat;
302	int version = 0, version_major, version_minor;
303#ifndef OPENSSL_NO_COMP
304	int j;
305	SSL_COMP *comp;
306#endif
307	int ret;
308	unsigned long mask, options = s->options;
309
310	ssl2_compat = (options & SSL_OP_NO_SSLv2) ? 0 : 1;
311
312	if (ssl2_compat && ssl23_no_ssl2_ciphers(s))
313		ssl2_compat = 0;
314
315	/*
316	 * SSL_OP_NO_X disables all protocols above X *if* there are
317	 * some protocols below X enabled. This is required in order
318	 * to maintain "version capability" vector contiguous. So
319	 * that if application wants to disable TLS1.0 in favour of
320	 * TLS1>=1, it would be insufficient to pass SSL_NO_TLSv1, the
321	 * answer is SSL_OP_NO_TLSv1|SSL_OP_NO_SSLv3|SSL_OP_NO_SSLv2.
322	 */
323	mask =	SSL_OP_NO_TLSv1_1|SSL_OP_NO_TLSv1
324#if !defined(OPENSSL_NO_SSL3)
325		|SSL_OP_NO_SSLv3
326#endif
327#if !defined(OPENSSL_NO_SSL2)
328		|(ssl2_compat?SSL_OP_NO_SSLv2:0)
329#endif
330		;
331#if !defined(OPENSSL_NO_TLS1_2_CLIENT)
332	version = TLS1_2_VERSION;
333
334	if ((options & SSL_OP_NO_TLSv1_2) && (options & mask) != mask)
335		version = TLS1_1_VERSION;
336#else
337	version = TLS1_1_VERSION;
338#endif
339	mask &= ~SSL_OP_NO_TLSv1_1;
340	if ((options & SSL_OP_NO_TLSv1_1) && (options & mask) != mask)
341		version = TLS1_VERSION;
342	mask &= ~SSL_OP_NO_TLSv1;
343#if !defined(OPENSSL_NO_SSL3)
344	if ((options & SSL_OP_NO_TLSv1) && (options & mask) != mask)
345		version = SSL3_VERSION;
346	mask &= ~SSL_OP_NO_SSLv3;
347#endif
348#if !defined(OPENSSL_NO_SSL2)
349	if ((options & SSL_OP_NO_SSLv3) && (options & mask) != mask)
350		version = SSL2_VERSION;
351#endif
352
353#ifndef OPENSSL_NO_TLSEXT
354	if (version != SSL2_VERSION)
355		{
356		/* have to disable SSL 2.0 compatibility if we need TLS extensions */
357
358		if (s->tlsext_hostname != NULL)
359			ssl2_compat = 0;
360		if (s->tlsext_status_type != -1)
361			ssl2_compat = 0;
362#ifdef TLSEXT_TYPE_opaque_prf_input
363		if (s->ctx->tlsext_opaque_prf_input_callback != 0 || s->tlsext_opaque_prf_input != NULL)
364			ssl2_compat = 0;
365#endif
366		}
367#endif
368
369	buf=(unsigned char *)s->init_buf->data;
370	if (s->state == SSL23_ST_CW_CLNT_HELLO_A)
371		{
372#if 0
373		/* don't reuse session-id's */
374		if (!ssl_get_new_session(s,0))
375			{
376			return(-1);
377			}
378#endif
379
380		p=s->s3->client_random;
381		if (ssl_fill_hello_random(s, 0, p, SSL3_RANDOM_SIZE) <= 0)
382			return -1;
383
384		if (version == TLS1_2_VERSION)
385			{
386			version_major = TLS1_2_VERSION_MAJOR;
387			version_minor = TLS1_2_VERSION_MINOR;
388			}
389		else if (version == TLS1_1_VERSION)
390			{
391			version_major = TLS1_1_VERSION_MAJOR;
392			version_minor = TLS1_1_VERSION_MINOR;
393			}
394		else if (version == TLS1_VERSION)
395			{
396			version_major = TLS1_VERSION_MAJOR;
397			version_minor = TLS1_VERSION_MINOR;
398			}
399#ifdef OPENSSL_FIPS
400		else if(FIPS_mode())
401			{
402			SSLerr(SSL_F_SSL23_CLIENT_HELLO,
403					SSL_R_ONLY_TLS_ALLOWED_IN_FIPS_MODE);
404			return -1;
405			}
406#endif
407		else if (version == SSL3_VERSION)
408			{
409			version_major = SSL3_VERSION_MAJOR;
410			version_minor = SSL3_VERSION_MINOR;
411			}
412		else if (version == SSL2_VERSION)
413			{
414			version_major = SSL2_VERSION_MAJOR;
415			version_minor = SSL2_VERSION_MINOR;
416			}
417		else
418			{
419			SSLerr(SSL_F_SSL23_CLIENT_HELLO,SSL_R_NO_PROTOCOLS_AVAILABLE);
420			return(-1);
421			}
422
423		s->client_version = version;
424
425		if (ssl2_compat)
426			{
427			/* create SSL 2.0 compatible Client Hello */
428
429			/* two byte record header will be written last */
430			d = &(buf[2]);
431			p = d + 9; /* leave space for message type, version, individual length fields */
432
433			*(d++) = SSL2_MT_CLIENT_HELLO;
434			*(d++) = version_major;
435			*(d++) = version_minor;
436
437			/* Ciphers supported */
438			i=ssl_cipher_list_to_bytes(s,SSL_get_ciphers(s),p,0);
439			if (i == 0)
440				{
441				/* no ciphers */
442				SSLerr(SSL_F_SSL23_CLIENT_HELLO,SSL_R_NO_CIPHERS_AVAILABLE);
443				return -1;
444				}
445			s2n(i,d);
446			p+=i;
447
448			/* put in the session-id length (zero since there is no reuse) */
449#if 0
450			s->session->session_id_length=0;
451#endif
452			s2n(0,d);
453
454			if (s->options & SSL_OP_NETSCAPE_CHALLENGE_BUG)
455				ch_len=SSL2_CHALLENGE_LENGTH;
456			else
457				ch_len=SSL2_MAX_CHALLENGE_LENGTH;
458
459			/* write out sslv2 challenge */
460			/* Note that ch_len must be <= SSL3_RANDOM_SIZE (32),
461			   because it is one of SSL2_MAX_CHALLENGE_LENGTH (32)
462			   or SSL2_MAX_CHALLENGE_LENGTH (16), but leave the
463			   check in for futurproofing */
464			if (SSL3_RANDOM_SIZE < ch_len)
465				i=SSL3_RANDOM_SIZE;
466			else
467				i=ch_len;
468			s2n(i,d);
469			memset(&(s->s3->client_random[0]),0,SSL3_RANDOM_SIZE);
470			if (RAND_pseudo_bytes(&(s->s3->client_random[SSL3_RANDOM_SIZE-i]),i) <= 0)
471				return -1;
472
473			memcpy(p,&(s->s3->client_random[SSL3_RANDOM_SIZE-i]),i);
474			p+=i;
475
476			i= p- &(buf[2]);
477			buf[0]=((i>>8)&0xff)|0x80;
478			buf[1]=(i&0xff);
479
480			/* number of bytes to write */
481			s->init_num=i+2;
482			s->init_off=0;
483
484			ssl3_finish_mac(s,&(buf[2]),i);
485			}
486		else
487			{
488			/* create Client Hello in SSL 3.0/TLS 1.0 format */
489
490			/* do the record header (5 bytes) and handshake message header (4 bytes) last */
491			d = p = &(buf[9]);
492
493			*(p++) = version_major;
494			*(p++) = version_minor;
495
496			/* Random stuff */
497			memcpy(p, s->s3->client_random, SSL3_RANDOM_SIZE);
498			p += SSL3_RANDOM_SIZE;
499
500			/* Session ID (zero since there is no reuse) */
501			*(p++) = 0;
502
503			/* Ciphers supported (using SSL 3.0/TLS 1.0 format) */
504			i=ssl_cipher_list_to_bytes(s,SSL_get_ciphers(s),&(p[2]),ssl3_put_cipher_by_char);
505			if (i == 0)
506				{
507				SSLerr(SSL_F_SSL23_CLIENT_HELLO,SSL_R_NO_CIPHERS_AVAILABLE);
508				return -1;
509				}
510#ifdef OPENSSL_MAX_TLS1_2_CIPHER_LENGTH
511			/* Some servers hang if client hello > 256 bytes
512			 * as hack workaround chop number of supported ciphers
513			 * to keep it well below this if we use TLS v1.2
514			 */
515			if (TLS1_get_version(s) >= TLS1_2_VERSION
516				&& i > OPENSSL_MAX_TLS1_2_CIPHER_LENGTH)
517				i = OPENSSL_MAX_TLS1_2_CIPHER_LENGTH & ~1;
518#endif
519			s2n(i,p);
520			p+=i;
521
522			/* COMPRESSION */
523#ifdef OPENSSL_NO_COMP
524			*(p++)=1;
525#else
526			if ((s->options & SSL_OP_NO_COMPRESSION)
527						|| !s->ctx->comp_methods)
528				j=0;
529			else
530				j=sk_SSL_COMP_num(s->ctx->comp_methods);
531			*(p++)=1+j;
532			for (i=0; i<j; i++)
533				{
534				comp=sk_SSL_COMP_value(s->ctx->comp_methods,i);
535				*(p++)=comp->id;
536				}
537#endif
538			*(p++)=0; /* Add the NULL method */
539
540#ifndef OPENSSL_NO_TLSEXT
541			/* TLS extensions*/
542			if (ssl_prepare_clienthello_tlsext(s) <= 0)
543				{
544				SSLerr(SSL_F_SSL23_CLIENT_HELLO,SSL_R_CLIENTHELLO_TLSEXT);
545				return -1;
546				}
547			if ((p = ssl_add_clienthello_tlsext(s, p, buf+SSL3_RT_MAX_PLAIN_LENGTH)) == NULL)
548				{
549				SSLerr(SSL_F_SSL23_CLIENT_HELLO,ERR_R_INTERNAL_ERROR);
550				return -1;
551				}
552#endif
553
554			l = p-d;
555
556			/* fill in 4-byte handshake header */
557			d=&(buf[5]);
558			*(d++)=SSL3_MT_CLIENT_HELLO;
559			l2n3(l,d);
560
561			l += 4;
562
563			if (l > SSL3_RT_MAX_PLAIN_LENGTH)
564				{
565				SSLerr(SSL_F_SSL23_CLIENT_HELLO,ERR_R_INTERNAL_ERROR);
566				return -1;
567				}
568
569			/* fill in 5-byte record header */
570			d=buf;
571			*(d++) = SSL3_RT_HANDSHAKE;
572			*(d++) = version_major;
573			/* Some servers hang if we use long client hellos
574			 * and a record number > TLS 1.0.
575			 */
576			if (TLS1_get_client_version(s) > TLS1_VERSION)
577				*(d++) = 1;
578			else
579				*(d++) = version_minor;
580			s2n((int)l,d);
581
582			/* number of bytes to write */
583			s->init_num=p-buf;
584			s->init_off=0;
585
586			ssl3_finish_mac(s,&(buf[5]), s->init_num - 5);
587			}
588
589		s->state=SSL23_ST_CW_CLNT_HELLO_B;
590		s->init_off=0;
591		}
592
593	/* SSL3_ST_CW_CLNT_HELLO_B */
594	ret = ssl23_write_bytes(s);
595
596	if ((ret >= 2) && s->msg_callback)
597		{
598		/* Client Hello has been sent; tell msg_callback */
599
600		if (ssl2_compat)
601			s->msg_callback(1, SSL2_VERSION, 0, s->init_buf->data+2, ret-2, s, s->msg_callback_arg);
602		else
603			s->msg_callback(1, version, SSL3_RT_HANDSHAKE, s->init_buf->data+5, ret-5, s, s->msg_callback_arg);
604		}
605
606	return ret;
607	}
608
609static int ssl23_get_server_hello(SSL *s)
610	{
611	char buf[8];
612	unsigned char *p;
613	int i;
614	int n;
615
616	n=ssl23_read_bytes(s,7);
617
618	if (n != 7) return(n);
619	p=s->packet;
620
621	memcpy(buf,p,n);
622
623	if ((p[0] & 0x80) && (p[2] == SSL2_MT_SERVER_HELLO) &&
624		(p[5] == 0x00) && (p[6] == 0x02))
625		{
626#ifdef OPENSSL_NO_SSL2
627		SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_R_UNSUPPORTED_PROTOCOL);
628		goto err;
629#else
630		/* we are talking sslv2 */
631		/* we need to clean up the SSLv3 setup and put in the
632		 * sslv2 stuff. */
633		int ch_len;
634
635		if (s->options & SSL_OP_NO_SSLv2)
636			{
637			SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_R_UNSUPPORTED_PROTOCOL);
638			goto err;
639			}
640		if (s->s2 == NULL)
641			{
642			if (!ssl2_new(s))
643				goto err;
644			}
645		else
646			ssl2_clear(s);
647
648		if (s->options & SSL_OP_NETSCAPE_CHALLENGE_BUG)
649			ch_len=SSL2_CHALLENGE_LENGTH;
650		else
651			ch_len=SSL2_MAX_CHALLENGE_LENGTH;
652
653		/* write out sslv2 challenge */
654		/* Note that ch_len must be <= SSL3_RANDOM_SIZE (32), because
655		   it is one of SSL2_MAX_CHALLENGE_LENGTH (32) or
656		   SSL2_MAX_CHALLENGE_LENGTH (16), but leave the check in for
657		   futurproofing */
658		i=(SSL3_RANDOM_SIZE < ch_len)
659			?SSL3_RANDOM_SIZE:ch_len;
660		s->s2->challenge_length=i;
661		memcpy(s->s2->challenge,
662			&(s->s3->client_random[SSL3_RANDOM_SIZE-i]),i);
663
664		if (s->s3 != NULL) ssl3_free(s);
665
666		if (!BUF_MEM_grow_clean(s->init_buf,
667			SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER))
668			{
669			SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,ERR_R_BUF_LIB);
670			goto err;
671			}
672
673		s->state=SSL2_ST_GET_SERVER_HELLO_A;
674		if (!(s->client_version == SSL2_VERSION))
675			/* use special padding (SSL 3.0 draft/RFC 2246, App. E.2) */
676			s->s2->ssl2_rollback=1;
677
678		/* setup the 7 bytes we have read so we get them from
679		 * the sslv2 buffer */
680		s->rstate=SSL_ST_READ_HEADER;
681		s->packet_length=n;
682		s->packet= &(s->s2->rbuf[0]);
683		memcpy(s->packet,buf,n);
684		s->s2->rbuf_left=n;
685		s->s2->rbuf_offs=0;
686
687		/* we have already written one */
688		s->s2->write_sequence=1;
689
690		s->method=SSLv2_client_method();
691		s->handshake_func=s->method->ssl_connect;
692#endif
693		}
694	else if (p[1] == SSL3_VERSION_MAJOR &&
695	         p[2] <= TLS1_2_VERSION_MINOR &&
696	         ((p[0] == SSL3_RT_HANDSHAKE && p[5] == SSL3_MT_SERVER_HELLO) ||
697	          (p[0] == SSL3_RT_ALERT && p[3] == 0 && p[4] == 2)))
698		{
699		/* we have sslv3 or tls1 (server hello or alert) */
700
701		if ((p[2] == SSL3_VERSION_MINOR) &&
702			!(s->options & SSL_OP_NO_SSLv3))
703			{
704#ifdef OPENSSL_FIPS
705			if(FIPS_mode())
706				{
707				SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,
708					SSL_R_ONLY_TLS_ALLOWED_IN_FIPS_MODE);
709				goto err;
710				}
711#endif
712			s->version=SSL3_VERSION;
713			s->method=SSLv3_client_method();
714			}
715		else if ((p[2] == TLS1_VERSION_MINOR) &&
716			!(s->options & SSL_OP_NO_TLSv1))
717			{
718			s->version=TLS1_VERSION;
719			s->method=TLSv1_client_method();
720			}
721		else if ((p[2] == TLS1_1_VERSION_MINOR) &&
722			!(s->options & SSL_OP_NO_TLSv1_1))
723			{
724			s->version=TLS1_1_VERSION;
725			s->method=TLSv1_1_client_method();
726			}
727		else if ((p[2] == TLS1_2_VERSION_MINOR) &&
728			!(s->options & SSL_OP_NO_TLSv1_2))
729			{
730			s->version=TLS1_2_VERSION;
731			s->method=TLSv1_2_client_method();
732			}
733		else
734			{
735			SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_R_UNSUPPORTED_PROTOCOL);
736			goto err;
737			}
738
739		if (p[0] == SSL3_RT_ALERT && p[5] != SSL3_AL_WARNING)
740			{
741			/* fatal alert */
742
743			void (*cb)(const SSL *ssl,int type,int val)=NULL;
744			int j;
745
746			if (s->info_callback != NULL)
747				cb=s->info_callback;
748			else if (s->ctx->info_callback != NULL)
749				cb=s->ctx->info_callback;
750
751			i=p[5];
752			if (cb != NULL)
753				{
754				j=(i<<8)|p[6];
755				cb(s,SSL_CB_READ_ALERT,j);
756				}
757
758			if (s->msg_callback)
759				s->msg_callback(0, s->version, SSL3_RT_ALERT, p+5, 2, s, s->msg_callback_arg);
760
761			s->rwstate=SSL_NOTHING;
762			SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_AD_REASON_OFFSET+p[6]);
763			goto err;
764			}
765
766		if (!ssl_init_wbio_buffer(s,1)) goto err;
767
768		/* we are in this state */
769		s->state=SSL3_ST_CR_SRVR_HELLO_A;
770
771		/* put the 7 bytes we have read into the input buffer
772		 * for SSLv3 */
773		s->rstate=SSL_ST_READ_HEADER;
774		s->packet_length=n;
775		if (s->s3->rbuf.buf == NULL)
776			if (!ssl3_setup_read_buffer(s))
777				goto err;
778		s->packet= &(s->s3->rbuf.buf[0]);
779		memcpy(s->packet,buf,n);
780		s->s3->rbuf.left=n;
781		s->s3->rbuf.offset=0;
782
783		s->handshake_func=s->method->ssl_connect;
784		}
785	else
786		{
787		SSLerr(SSL_F_SSL23_GET_SERVER_HELLO,SSL_R_UNKNOWN_PROTOCOL);
788		goto err;
789		}
790	s->init_num=0;
791
792	/* Since, if we are sending a ssl23 client hello, we are not
793	 * reusing a session-id */
794	if (!ssl_get_new_session(s,0))
795		goto err;
796
797	return(SSL_connect(s));
798err:
799	return(-1);
800	}
801