Fix warning where BIO_FLAGS_UPLINK was being redefined.
[openssl.git] / ssl / s23_srvr.c
1 /* ssl/s23_srvr.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_server_method(int ver);
120 int ssl23_get_client_hello(SSL *s);
121 static const SSL_METHOD *ssl23_get_server_method(int ver)
122         {
123 #ifndef OPENSSL_NO_SSL2
124         if (ver == SSL2_VERSION)
125                 return(SSLv2_server_method());
126 #endif
127 #ifndef OPENSSL_NO_SSL3
128         if (ver == SSL3_VERSION)
129                 return(SSLv3_server_method());
130 #endif
131         if (ver == TLS1_VERSION)
132                 return(TLSv1_server_method());
133         else
134                 return(NULL);
135         }
136
137 IMPLEMENT_ssl23_meth_func(SSLv23_server_method,
138                         ssl23_accept,
139                         ssl_undefined_function,
140                         ssl23_get_server_method)
141
142 int ssl23_accept(SSL *s)
143         {
144         BUF_MEM *buf;
145         unsigned long Time=(unsigned long)time(NULL);
146         void (*cb)(const SSL *ssl,int type,int val)=NULL;
147         int ret= -1;
148         int new_state,state;
149
150         RAND_add(&Time,sizeof(Time),0);
151         ERR_clear_error();
152         clear_sys_error();
153
154         if (s->info_callback != NULL)
155                 cb=s->info_callback;
156         else if (s->ctx->info_callback != NULL)
157                 cb=s->ctx->info_callback;
158         
159         s->in_handshake++;
160         if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s); 
161
162         for (;;)
163                 {
164                 state=s->state;
165
166                 switch(s->state)
167                         {
168                 case SSL_ST_BEFORE:
169                 case SSL_ST_ACCEPT:
170                 case SSL_ST_BEFORE|SSL_ST_ACCEPT:
171                 case SSL_ST_OK|SSL_ST_ACCEPT:
172
173                         s->server=1;
174                         if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
175
176                         /* s->version=SSL3_VERSION; */
177                         s->type=SSL_ST_ACCEPT;
178
179                         if (s->init_buf == NULL)
180                                 {
181                                 if ((buf=BUF_MEM_new()) == NULL)
182                                         {
183                                         ret= -1;
184                                         goto end;
185                                         }
186                                 if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH))
187                                         {
188                                         BUF_MEM_free(buf);
189                                         ret= -1;
190                                         goto end;
191                                         }
192                                 s->init_buf=buf;
193                                 }
194
195                         ssl3_init_finished_mac(s);
196
197                         s->state=SSL23_ST_SR_CLNT_HELLO_A;
198                         s->ctx->stats.sess_accept++;
199                         s->init_num=0;
200                         break;
201
202                 case SSL23_ST_SR_CLNT_HELLO_A:
203                 case SSL23_ST_SR_CLNT_HELLO_B:
204
205                         s->shutdown=0;
206                         ret=ssl23_get_client_hello(s);
207                         if (ret >= 0) cb=NULL;
208                         goto end;
209                         /* break; */
210
211                 default:
212                         SSLerr(SSL_F_SSL23_ACCEPT,SSL_R_UNKNOWN_STATE);
213                         ret= -1;
214                         goto end;
215                         /* break; */
216                         }
217
218                 if ((cb != NULL) && (s->state != state))
219                         {
220                         new_state=s->state;
221                         s->state=state;
222                         cb(s,SSL_CB_ACCEPT_LOOP,1);
223                         s->state=new_state;
224                         }
225                 }
226 end:
227         s->in_handshake--;
228         if (cb != NULL)
229                 cb(s,SSL_CB_ACCEPT_EXIT,ret);
230         return(ret);
231         }
232
233
234 int ssl23_get_client_hello(SSL *s)
235         {
236         char buf_space[11]; /* Request this many bytes in initial read.
237                              * We can detect SSL 3.0/TLS 1.0 Client Hellos
238                              * ('type == 3') correctly only when the following
239                              * is in a single record, which is not guaranteed by
240                              * the protocol specification:
241                              * Byte  Content
242                              *  0     type            \
243                              *  1/2   version          > record header
244                              *  3/4   length          /
245                              *  5     msg_type        \
246                              *  6-8   length           > Client Hello message
247                              *  9/10  client_version  /
248                              */
249         char *buf= &(buf_space[0]);
250         unsigned char *p,*d,*d_len,*dd;
251         unsigned int i;
252         unsigned int csl,sil,cl;
253         int n=0,j;
254         int type=0;
255         int v[2];
256
257         if (s->state == SSL23_ST_SR_CLNT_HELLO_A)
258                 {
259                 /* read the initial header */
260                 v[0]=v[1]=0;
261
262                 if (!ssl3_setup_buffers(s)) goto err;
263
264                 n=ssl23_read_bytes(s, sizeof buf_space);
265                 if (n != sizeof buf_space) return(n); /* n == -1 || n == 0 */
266
267                 p=s->packet;
268
269                 memcpy(buf,p,n);
270
271                 if ((p[0] & 0x80) && (p[2] == SSL2_MT_CLIENT_HELLO))
272                         {
273                         /*
274                          * SSLv2 header
275                          */
276                         if ((p[3] == 0x00) && (p[4] == 0x02))
277                                 {
278                                 v[0]=p[3]; v[1]=p[4];
279                                 /* SSLv2 */
280                                 if (!(s->options & SSL_OP_NO_SSLv2))
281                                         type=1;
282                                 }
283                         else if (p[3] == SSL3_VERSION_MAJOR)
284                                 {
285                                 v[0]=p[3]; v[1]=p[4];
286                                 /* SSLv3/TLSv1 */
287                                 if (p[4] >= TLS1_VERSION_MINOR)
288                                         {
289                                         if (!(s->options & SSL_OP_NO_TLSv1))
290                                                 {
291                                                 s->version=TLS1_VERSION;
292                                                 /* type=2; */ /* done later to survive restarts */
293                                                 s->state=SSL23_ST_SR_CLNT_HELLO_B;
294                                                 }
295                                         else if (!(s->options & SSL_OP_NO_SSLv3))
296                                                 {
297                                                 s->version=SSL3_VERSION;
298                                                 /* type=2; */
299                                                 s->state=SSL23_ST_SR_CLNT_HELLO_B;
300                                                 }
301                                         else if (!(s->options & SSL_OP_NO_SSLv2))
302                                                 {
303                                                 type=1;
304                                                 }
305                                         }
306                                 else if (!(s->options & SSL_OP_NO_SSLv3))
307                                         {
308                                         s->version=SSL3_VERSION;
309                                         /* type=2; */
310                                         s->state=SSL23_ST_SR_CLNT_HELLO_B;
311                                         }
312                                 else if (!(s->options & SSL_OP_NO_SSLv2))
313                                         type=1;
314
315                                 }
316                         }
317                 else if ((p[0] == SSL3_RT_HANDSHAKE) &&
318                          (p[1] == SSL3_VERSION_MAJOR) &&
319                          (p[5] == SSL3_MT_CLIENT_HELLO) &&
320                          ((p[3] == 0 && p[4] < 5 /* silly record length? */)
321                                 || (p[9] >= p[1])))
322                         {
323                         /*
324                          * SSLv3 or tls1 header
325                          */
326                         
327                         v[0]=p[1]; /* major version (= SSL3_VERSION_MAJOR) */
328                         /* We must look at client_version inside the Client Hello message
329                          * to get the correct minor version.
330                          * However if we have only a pathologically small fragment of the
331                          * Client Hello message, this would be difficult, and we'd have
332                          * to read more records to find out.
333                          * No known SSL 3.0 client fragments ClientHello like this,
334                          * so we simply reject such connections to avoid
335                          * protocol version downgrade attacks. */
336                         if (p[3] == 0 && p[4] < 6)
337                                 {
338                                 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_TOO_SMALL);
339                                 goto err;
340                                 }
341                         /* if major version number > 3 set minor to a value
342                          * which will use the highest version 3 we support.
343                          * If TLS 2.0 ever appears we will need to revise
344                          * this....
345                          */
346                         if (p[9] > SSL3_VERSION_MAJOR)
347                                 v[1]=0xff;
348                         else
349                                 v[1]=p[10]; /* minor version according to client_version */
350                         if (v[1] >= TLS1_VERSION_MINOR)
351                                 {
352                                 if (!(s->options & SSL_OP_NO_TLSv1))
353                                         {
354                                         s->version=TLS1_VERSION;
355                                         type=3;
356                                         }
357                                 else if (!(s->options & SSL_OP_NO_SSLv3))
358                                         {
359                                         s->version=SSL3_VERSION;
360                                         type=3;
361                                         }
362                                 }
363                         else
364                                 {
365                                 /* client requests SSL 3.0 */
366                                 if (!(s->options & SSL_OP_NO_SSLv3))
367                                         {
368                                         s->version=SSL3_VERSION;
369                                         type=3;
370                                         }
371                                 else if (!(s->options & SSL_OP_NO_TLSv1))
372                                         {
373                                         /* we won't be able to use TLS of course,
374                                          * but this will send an appropriate alert */
375                                         s->version=TLS1_VERSION;
376                                         type=3;
377                                         }
378                                 }
379                         }
380                 else if ((strncmp("GET ", (char *)p,4) == 0) ||
381                          (strncmp("POST ",(char *)p,5) == 0) ||
382                          (strncmp("HEAD ",(char *)p,5) == 0) ||
383                          (strncmp("PUT ", (char *)p,4) == 0))
384                         {
385                         SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_HTTP_REQUEST);
386                         goto err;
387                         }
388                 else if (strncmp("CONNECT",(char *)p,7) == 0)
389                         {
390                         SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_HTTPS_PROXY_REQUEST);
391                         goto err;
392                         }
393                 }
394
395         /* ensure that TLS_MAX_VERSION is up-to-date */
396         OPENSSL_assert(s->version <= TLS_MAX_VERSION);
397
398         if (s->state == SSL23_ST_SR_CLNT_HELLO_B)
399                 {
400                 /* we have SSLv3/TLSv1 in an SSLv2 header
401                  * (other cases skip this state) */
402
403                 type=2;
404                 p=s->packet;
405                 v[0] = p[3]; /* == SSL3_VERSION_MAJOR */
406                 v[1] = p[4];
407
408                 /* An SSLv3/TLSv1 backwards-compatible CLIENT-HELLO in an SSLv2
409                  * header is sent directly on the wire, not wrapped as a TLS
410                  * record. It's format is:
411                  * Byte  Content
412                  * 0-1   msg_length
413                  * 2     msg_type
414                  * 3-4   version
415                  * 5-6   cipher_spec_length
416                  * 7-8   session_id_length
417                  * 9-10  challenge_length
418                  * ...   ...
419                  */
420                 n=((p[0]&0x7f)<<8)|p[1];
421                 if (n > (1024*4))
422                         {
423                         SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_TOO_LARGE);
424                         goto err;
425                         }
426                 if (n < 9)
427                         {
428                         SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_LENGTH_MISMATCH);
429                         goto err;
430                         }
431
432                 j=ssl23_read_bytes(s,n+2);
433                 /* We previously read 11 bytes, so if j > 0, we must have
434                  * j == n+2 == s->packet_length. We have at least 11 valid
435                  * packet bytes. */
436                 if (j <= 0) return(j);
437
438                 ssl3_finish_mac(s, s->packet+2, s->packet_length-2);
439                 if (s->msg_callback)
440                         s->msg_callback(0, SSL2_VERSION, 0, s->packet+2, s->packet_length-2, s, s->msg_callback_arg); /* CLIENT-HELLO */
441
442                 p=s->packet;
443                 p+=5;
444                 n2s(p,csl);
445                 n2s(p,sil);
446                 n2s(p,cl);
447                 d=(unsigned char *)s->init_buf->data;
448                 if ((csl+sil+cl+11) != s->packet_length) /* We can't have TLS extensions in SSL 2.0 format
449                                                           * Client Hello, can we? Error condition should be
450                                                           * '>' otherweise */
451                         {
452                         SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_RECORD_LENGTH_MISMATCH);
453                         goto err;
454                         }
455
456                 /* record header: msg_type ... */
457                 *(d++) = SSL3_MT_CLIENT_HELLO;
458                 /* ... and length (actual value will be written later) */
459                 d_len = d;
460                 d += 3;
461
462                 /* client_version */
463                 *(d++) = SSL3_VERSION_MAJOR; /* == v[0] */
464                 *(d++) = v[1];
465
466                 /* lets populate the random area */
467                 /* get the challenge_length */
468                 i=(cl > SSL3_RANDOM_SIZE)?SSL3_RANDOM_SIZE:cl;
469                 memset(d,0,SSL3_RANDOM_SIZE);
470                 memcpy(&(d[SSL3_RANDOM_SIZE-i]),&(p[csl+sil]),i);
471                 d+=SSL3_RANDOM_SIZE;
472
473                 /* no session-id reuse */
474                 *(d++)=0;
475
476                 /* ciphers */
477                 j=0;
478                 dd=d;
479                 d+=2;
480                 for (i=0; i<csl; i+=3)
481                         {
482                         if (p[i] != 0) continue;
483                         *(d++)=p[i+1];
484                         *(d++)=p[i+2];
485                         j+=2;
486                         }
487                 s2n(j,dd);
488
489                 /* COMPRESSION */
490                 *(d++)=1;
491                 *(d++)=0;
492                 
493 #if 0
494                 /* copy any remaining data with may be extensions */
495                 p = p+csl+sil+cl;
496                 while (p <  s->packet+s->packet_length)
497                         {
498                         *(d++)=*(p++);
499                         }
500 #endif
501
502                 i = (d-(unsigned char *)s->init_buf->data) - 4;
503                 l2n3((long)i, d_len);
504
505                 /* get the data reused from the init_buf */
506                 s->s3->tmp.reuse_message=1;
507                 s->s3->tmp.message_type=SSL3_MT_CLIENT_HELLO;
508                 s->s3->tmp.message_size=i;
509                 }
510
511         /* imaginary new state (for program structure): */
512         /* s->state = SSL23_SR_CLNT_HELLO_C */
513
514         if (type == 1)
515                 {
516 #ifdef OPENSSL_NO_SSL2
517                 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_UNSUPPORTED_PROTOCOL);
518                 goto err;
519 #else
520                 /* we are talking sslv2 */
521                 /* we need to clean up the SSLv3/TLSv1 setup and put in the
522                  * sslv2 stuff. */
523
524                 if (s->s2 == NULL)
525                         {
526                         if (!ssl2_new(s))
527                                 goto err;
528                         }
529                 else
530                         ssl2_clear(s);
531
532                 if (s->s3 != NULL) ssl3_free(s);
533
534                 if (!BUF_MEM_grow_clean(s->init_buf,
535                         SSL2_MAX_RECORD_LENGTH_3_BYTE_HEADER))
536                         {
537                         goto err;
538                         }
539
540                 s->state=SSL2_ST_GET_CLIENT_HELLO_A;
541                 if (s->options & SSL_OP_NO_TLSv1 && s->options & SSL_OP_NO_SSLv3)
542                         s->s2->ssl2_rollback=0;
543                 else
544                         /* reject SSL 2.0 session if client supports SSL 3.0 or TLS 1.0
545                          * (SSL 3.0 draft/RFC 2246, App. E.2) */
546                         s->s2->ssl2_rollback=1;
547
548                 /* setup the n bytes we have read so we get them from
549                  * the sslv2 buffer */
550                 s->rstate=SSL_ST_READ_HEADER;
551                 s->packet_length=n;
552                 s->packet= &(s->s2->rbuf[0]);
553                 memcpy(s->packet,buf,n);
554                 s->s2->rbuf_left=n;
555                 s->s2->rbuf_offs=0;
556
557                 s->method=SSLv2_server_method();
558                 s->handshake_func=s->method->ssl_accept;
559 #endif
560                 }
561
562         if ((type == 2) || (type == 3))
563                 {
564                 /* we have SSLv3/TLSv1 (type 2: SSL2 style, type 3: SSL3/TLS style) */
565                 const SSL_METHOD *new_method;
566                 new_method = ssl23_get_server_method(s->version);
567                 if (new_method == NULL)
568                         {
569                         SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_UNSUPPORTED_PROTOCOL);
570                         goto err;
571                         }
572                 s->method = new_method;
573
574                 if (!ssl_init_wbio_buffer(s,1)) goto err;
575
576                 /* we are in this state */
577                 s->state=SSL3_ST_SR_CLNT_HELLO_A;
578
579                 if (type == 3)
580                         {
581                         /* put the 'n' bytes we have read into the input buffer
582                          * for SSLv3 */
583                         s->rstate=SSL_ST_READ_HEADER;
584                         s->packet_length=n;
585                         if (s->s3->rbuf.buf == NULL)
586                                 if (!ssl3_setup_read_buffer(s))
587                                         goto err;
588
589                         s->packet= &(s->s3->rbuf.buf[0]);
590                         memcpy(s->packet,buf,n);
591                         s->s3->rbuf.left=n;
592                         s->s3->rbuf.offset=0;
593                         }
594                 else
595                         {
596                         s->packet_length=0;
597                         s->s3->rbuf.left=0;
598                         s->s3->rbuf.offset=0;
599                         }
600 #if 0 /* ssl3_get_client_hello does this */
601                 s->client_version=(v[0]<<8)|v[1];
602 #endif
603                 s->handshake_func=s->method->ssl_accept;
604                 }
605         
606         if ((type < 1) || (type > 3))
607                 {
608                 /* bad, very bad */
609                 SSLerr(SSL_F_SSL23_GET_CLIENT_HELLO,SSL_R_UNKNOWN_PROTOCOL);
610                 goto err;
611                 }
612         s->init_num=0;
613
614         if (buf != buf_space) OPENSSL_free(buf);
615         return(SSL_accept(s));
616 err:
617         if (buf != buf_space) OPENSSL_free(buf);
618         return(-1);
619         }