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