f90bb776667571f323c0384fad100d08f77ac774
[openssl.git] / ssl / s3_pkt.c
1 /* ssl/s3_pkt.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) 1998-2002 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 <errno.h>
114 #define USE_SOCKETS
115 #include "ssl_locl.h"
116 #include <openssl/evp.h>
117 #include <openssl/buffer.h>
118
119 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
120                          unsigned int len, int create_empty_fragment);
121 static int ssl3_get_record(SSL *s);
122
123 int ssl3_read_n(SSL *s, int n, int max, int extend)
124         {
125         /* If extend == 0, obtain new n-byte packet; if extend == 1, increase
126          * packet by another n bytes.
127          * The packet will be in the sub-array of s->s3->rbuf.buf specified
128          * by s->packet and s->packet_length.
129          * (If s->read_ahead is set, 'max' bytes may be stored in rbuf
130          * [plus s->packet_length bytes if extend == 1].)
131          */
132         int i,off,newb;
133
134         if (!extend)
135                 {
136                 /* start with empty packet ... */
137                 if (s->s3->rbuf.left == 0)
138                         s->s3->rbuf.offset = 0;
139                 s->packet = s->s3->rbuf.buf + s->s3->rbuf.offset;
140                 s->packet_length = 0;
141                 /* ... now we can act as if 'extend' was set */
142                 }
143
144         /* extend reads should not span multiple packets for DTLS */
145         if ( SSL_version(s) == DTLS1_VERSION &&
146                 extend)
147                 {
148                 if ( s->s3->rbuf.left > 0 && n > s->s3->rbuf.left)
149                         n = s->s3->rbuf.left;
150                 }
151
152         /* if there is enough in the buffer from a previous read, take some */
153         if (s->s3->rbuf.left >= (int)n)
154                 {
155                 s->packet_length+=n;
156                 s->s3->rbuf.left-=n;
157                 s->s3->rbuf.offset+=n;
158                 return(n);
159                 }
160
161         /* else we need to read more data */
162         if (!s->read_ahead)
163                 max=n;
164
165         {
166                 /* avoid buffer overflow */
167                 int max_max = s->s3->rbuf.len - s->packet_length;
168                 if (max > max_max)
169                         max = max_max;
170         }
171         if (n > max) /* does not happen */
172                 {
173                 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
174                 return -1;
175                 }
176
177         off = s->packet_length;
178         newb = s->s3->rbuf.left;
179         /* Move any available bytes to front of buffer:
180          * 'off' bytes already pointed to by 'packet',
181          * 'newb' extra ones at the end */
182         if (s->packet != s->s3->rbuf.buf)
183                 {
184                 /*  off > 0 */
185                 memmove(s->s3->rbuf.buf, s->packet, off+newb);
186                 s->packet = s->s3->rbuf.buf;
187                 }
188
189         while (newb < n)
190                 {
191                 /* Now we have off+newb bytes at the front of s->s3->rbuf.buf and need
192                  * to read in more until we have off+n (up to off+max if possible) */
193
194                 clear_sys_error();
195                 if (s->rbio != NULL)
196                         {
197                         s->rwstate=SSL_READING;
198                         i=BIO_read(s->rbio,     &(s->s3->rbuf.buf[off+newb]), max-newb);
199                         }
200                 else
201                         {
202                         SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
203                         i = -1;
204                         }
205
206                 if (i <= 0)
207                         {
208                         s->s3->rbuf.left = newb;
209                         return(i);
210                         }
211                 newb+=i;
212                 }
213
214         /* done reading, now the book-keeping */
215         s->s3->rbuf.offset = off + n;
216         s->s3->rbuf.left = newb - n;
217         s->packet_length += n;
218         s->rwstate=SSL_NOTHING;
219         return(n);
220         }
221
222 /* Call this to get a new input record.
223  * It will return <= 0 if more data is needed, normally due to an error
224  * or non-blocking IO.
225  * When it finishes, one packet has been decoded and can be found in
226  * ssl->s3->rrec.type    - is the type of record
227  * ssl->s3->rrec.data,   - data
228  * ssl->s3->rrec.length, - number of bytes
229  */
230 /* used only by ssl3_read_bytes */
231 static int ssl3_get_record(SSL *s)
232         {
233         int ssl_major,ssl_minor,al;
234         int enc_err,n,i,ret= -1;
235         SSL3_RECORD *rr;
236         SSL_SESSION *sess;
237         unsigned char *p;
238         unsigned char md[EVP_MAX_MD_SIZE];
239         short version;
240         unsigned int mac_size;
241         int clear=0;
242         size_t extra;
243         int decryption_failed_or_bad_record_mac = 0;
244         unsigned char *mac = NULL;
245
246         rr= &(s->s3->rrec);
247         sess=s->session;
248
249         if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
250                 extra=SSL3_RT_MAX_EXTRA;
251         else
252                 extra=0;
253         if (extra != s->s3->rbuf.len - SSL3_RT_MAX_PACKET_SIZE)
254                 {
255                 /* actually likely an application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER
256                  * set after ssl3_setup_buffers() was done */
257                 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
258                 return -1;
259                 }
260
261 again:
262         /* check if we have the header */
263         if (    (s->rstate != SSL_ST_READ_BODY) ||
264                 (s->packet_length < SSL3_RT_HEADER_LENGTH)) 
265                 {
266                 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
267                 if (n <= 0) return(n); /* error or non-blocking */
268                 s->rstate=SSL_ST_READ_BODY;
269
270                 p=s->packet;
271
272                 /* Pull apart the header into the SSL3_RECORD */
273                 rr->type= *(p++);
274                 ssl_major= *(p++);
275                 ssl_minor= *(p++);
276                 version=(ssl_major<<8)|ssl_minor;
277                 n2s(p,rr->length);
278
279                 /* Lets check version */
280                 if (s->first_packet)
281                         {
282                         s->first_packet=0;
283                         }
284                 else
285                         {
286                         if (version != s->version)
287                                 {
288                                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
289                                 /* Send back error using their
290                                  * version number :-) */
291                                 s->version=version;
292                                 al=SSL_AD_PROTOCOL_VERSION;
293                                 goto f_err;
294                                 }
295                         }
296
297                 if ((version>>8) != SSL3_VERSION_MAJOR)
298                         {
299                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
300                         goto err;
301                         }
302
303                 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
304                         {
305                         al=SSL_AD_RECORD_OVERFLOW;
306                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
307                         goto f_err;
308                         }
309
310                 /* now s->rstate == SSL_ST_READ_BODY */
311                 }
312
313         /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
314
315         if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
316                 {
317                 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
318                 i=rr->length;
319                 n=ssl3_read_n(s,i,i,1);
320                 if (n <= 0) return(n); /* error or non-blocking io */
321                 /* now n == rr->length,
322                  * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
323                 }
324
325         s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
326
327         /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
328          * and we have that many bytes in s->packet
329          */
330         rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
331
332         /* ok, we can now read from 's->packet' data into 'rr'
333          * rr->input points at rr->length bytes, which
334          * need to be copied into rr->data by either
335          * the decryption or by the decompression
336          * When the data is 'copied' into the rr->data buffer,
337          * rr->input will be pointed at the new buffer */ 
338
339         /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
340          * rr->length bytes of encrypted compressed stuff. */
341
342         /* check is not needed I believe */
343         if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
344                 {
345                 al=SSL_AD_RECORD_OVERFLOW;
346                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
347                 goto f_err;
348                 }
349
350         /* decrypt in place in 'rr->input' */
351         rr->data=rr->input;
352
353         enc_err = s->method->ssl3_enc->enc(s,0);
354         if (enc_err <= 0)
355                 {
356                 if (enc_err == 0)
357                         /* SSLerr() and ssl3_send_alert() have been called */
358                         goto err;
359
360                 /* Otherwise enc_err == -1, which indicates bad padding
361                  * (rec->length has not been changed in this case).
362                  * To minimize information leaked via timing, we will perform
363                  * the MAC computation anyway. */
364                 decryption_failed_or_bad_record_mac = 1;
365                 }
366
367 #ifdef TLS_DEBUG
368 printf("dec %d\n",rr->length);
369 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
370 printf("\n");
371 #endif
372
373         /* r->length is now the compressed data plus mac */
374         if (    (sess == NULL) ||
375                 (s->enc_read_ctx == NULL) ||
376                 (s->read_hash == NULL))
377                 clear=1;
378
379         if (!clear)
380                 {
381                 mac_size=EVP_MD_size(s->read_hash);
382
383                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
384                         {
385 #if 0 /* OK only for stream ciphers (then rr->length is visible from ciphertext anyway) */
386                         al=SSL_AD_RECORD_OVERFLOW;
387                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG);
388                         goto f_err;
389 #else
390                         decryption_failed_or_bad_record_mac = 1;
391 #endif                  
392                         }
393                 /* check the MAC for rr->input (it's in mac_size bytes at the tail) */
394                 if (rr->length >= mac_size)
395                         {
396                         rr->length -= mac_size;
397                         mac = &rr->data[rr->length];
398                         }
399                 else
400                         {
401                         /* record (minus padding) is too short to contain a MAC */
402 #if 0 /* OK only for stream ciphers */
403                         al=SSL_AD_DECODE_ERROR;
404                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
405                         goto f_err;
406 #else
407                         decryption_failed_or_bad_record_mac = 1;
408                         rr->length = 0;
409 #endif
410                         }
411                 i=s->method->ssl3_enc->mac(s,md,0);
412                 if (mac == NULL || memcmp(md, mac, mac_size) != 0)
413                         {
414                         decryption_failed_or_bad_record_mac = 1;
415                         }
416                 }
417
418         if (decryption_failed_or_bad_record_mac)
419                 {
420                 /* A separate 'decryption_failed' alert was introduced with TLS 1.0,
421                  * SSL 3.0 only has 'bad_record_mac'.  But unless a decryption
422                  * failure is directly visible from the ciphertext anyway,
423                  * we should not reveal which kind of error occured -- this
424                  * might become visible to an attacker (e.g. via a logfile) */
425                 al=SSL_AD_BAD_RECORD_MAC;
426                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
427                 goto f_err;
428                 }
429
430         /* r->length is now just compressed */
431         if (s->expand != NULL)
432                 {
433                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
434                         {
435                         al=SSL_AD_RECORD_OVERFLOW;
436                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
437                         goto f_err;
438                         }
439                 if (!ssl3_do_uncompress(s))
440                         {
441                         al=SSL_AD_DECOMPRESSION_FAILURE;
442                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
443                         goto f_err;
444                         }
445                 }
446
447         if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
448                 {
449                 al=SSL_AD_RECORD_OVERFLOW;
450                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
451                 goto f_err;
452                 }
453
454         rr->off=0;
455         /* So at this point the following is true
456          * ssl->s3->rrec.type   is the type of record
457          * ssl->s3->rrec.length == number of bytes in record
458          * ssl->s3->rrec.off    == offset to first valid byte
459          * ssl->s3->rrec.data   == where to take bytes from, increment
460          *                         after use :-).
461          */
462
463         /* we have pulled in a full packet so zero things */
464         s->packet_length=0;
465
466         /* just read a 0 length packet */
467         if (rr->length == 0) goto again;
468
469         return(1);
470
471 f_err:
472         ssl3_send_alert(s,SSL3_AL_FATAL,al);
473 err:
474         return(ret);
475         }
476
477 int ssl3_do_uncompress(SSL *ssl)
478         {
479         int i;
480         SSL3_RECORD *rr;
481
482         rr= &(ssl->s3->rrec);
483         i=COMP_expand_block(ssl->expand,rr->comp,
484                 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
485         if (i < 0)
486                 return(0);
487         else
488                 rr->length=i;
489         rr->data=rr->comp;
490
491         return(1);
492         }
493
494 int ssl3_do_compress(SSL *ssl)
495         {
496         int i;
497         SSL3_RECORD *wr;
498
499         wr= &(ssl->s3->wrec);
500         i=COMP_compress_block(ssl->compress,wr->data,
501                 SSL3_RT_MAX_COMPRESSED_LENGTH,
502                 wr->input,(int)wr->length);
503         if (i < 0)
504                 return(0);
505         else
506                 wr->length=i;
507
508         wr->input=wr->data;
509         return(1);
510         }
511
512 /* Call this to write data in records of type 'type'
513  * It will return <= 0 if not all data has been sent or non-blocking IO.
514  */
515 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
516         {
517         const unsigned char *buf=buf_;
518         unsigned int tot,n,nw;
519         int i;
520
521         s->rwstate=SSL_NOTHING;
522         tot=s->s3->wnum;
523         s->s3->wnum=0;
524
525         if (SSL_in_init(s) && !s->in_handshake)
526                 {
527                 i=s->handshake_func(s);
528                 if (i < 0) return(i);
529                 if (i == 0)
530                         {
531                         SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
532                         return -1;
533                         }
534                 }
535
536         n=(len-tot);
537         for (;;)
538                 {
539                 if (n > SSL3_RT_MAX_PLAIN_LENGTH)
540                         nw=SSL3_RT_MAX_PLAIN_LENGTH;
541                 else
542                         nw=n;
543
544                 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
545                 if (i <= 0)
546                         {
547                         s->s3->wnum=tot;
548                         return i;
549                         }
550
551                 if ((i == (int)n) ||
552                         (type == SSL3_RT_APPLICATION_DATA &&
553                          (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
554                         {
555                         /* next chunk of data should get another prepended empty fragment
556                          * in ciphersuites with known-IV weakness: */
557                         s->s3->empty_fragment_done = 0;
558                         
559                         return tot+i;
560                         }
561
562                 n-=i;
563                 tot+=i;
564                 }
565         }
566
567 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
568                          unsigned int len, int create_empty_fragment)
569         {
570         unsigned char *p,*plen;
571         int i,mac_size,clear=0;
572         int prefix_len = 0;
573         SSL3_RECORD *wr;
574         SSL3_BUFFER *wb;
575         SSL_SESSION *sess;
576
577         /* first check if there is a SSL3_BUFFER still being written
578          * out.  This will happen with non blocking IO */
579         if (s->s3->wbuf.left != 0)
580                 return(ssl3_write_pending(s,type,buf,len));
581
582         /* If we have an alert to send, lets send it */
583         if (s->s3->alert_dispatch)
584                 {
585                 i=s->method->ssl_dispatch_alert(s);
586                 if (i <= 0)
587                         return(i);
588                 /* if it went, fall through and send more stuff */
589                 }
590
591         if (len == 0 && !create_empty_fragment)
592                 return 0;
593
594         wr= &(s->s3->wrec);
595         wb= &(s->s3->wbuf);
596         sess=s->session;
597
598         if (    (sess == NULL) ||
599                 (s->enc_write_ctx == NULL) ||
600                 (s->write_hash == NULL))
601                 clear=1;
602
603         if (clear)
604                 mac_size=0;
605         else
606                 mac_size=EVP_MD_size(s->write_hash);
607
608         /* 'create_empty_fragment' is true only when this function calls itself */
609         if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
610                 {
611                 /* countermeasure against known-IV weakness in CBC ciphersuites
612                  * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
613
614                 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
615                         {
616                         /* recursive function call with 'create_empty_fragment' set;
617                          * this prepares and buffers the data for an empty fragment
618                          * (these 'prefix_len' bytes are sent out later
619                          * together with the actual payload) */
620                         prefix_len = do_ssl3_write(s, type, buf, 0, 1);
621                         if (prefix_len <= 0)
622                                 goto err;
623
624                         if (s->s3->wbuf.len < (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE)
625                                 {
626                                 /* insufficient space */
627                                 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
628                                 goto err;
629                                 }
630                         }
631                 
632                 s->s3->empty_fragment_done = 1;
633                 }
634
635         p = wb->buf + prefix_len;
636
637         /* write the header */
638
639         *(p++)=type&0xff;
640         wr->type=type;
641
642         *(p++)=(s->version>>8);
643         *(p++)=s->version&0xff;
644
645         /* field where we are to write out packet length */
646         plen=p; 
647         p+=2;
648
649         /* lets setup the record stuff. */
650         wr->data=p;
651         wr->length=(int)len;
652         wr->input=(unsigned char *)buf;
653
654         /* we now 'read' from wr->input, wr->length bytes into
655          * wr->data */
656
657         /* first we compress */
658         if (s->compress != NULL)
659                 {
660                 if (!ssl3_do_compress(s))
661                         {
662                         SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
663                         goto err;
664                         }
665                 }
666         else
667                 {
668                 memcpy(wr->data,wr->input,wr->length);
669                 wr->input=wr->data;
670                 }
671
672         /* we should still have the output to wr->data and the input
673          * from wr->input.  Length should be wr->length.
674          * wr->data still points in the wb->buf */
675
676         if (mac_size != 0)
677                 {
678                 s->method->ssl3_enc->mac(s,&(p[wr->length]),1);
679                 wr->length+=mac_size;
680                 wr->input=p;
681                 wr->data=p;
682                 }
683
684         /* ssl3_enc can only have an error on read */
685         s->method->ssl3_enc->enc(s,1);
686
687         /* record length after mac and block padding */
688         s2n(wr->length,plen);
689
690         /* we should now have
691          * wr->data pointing to the encrypted data, which is
692          * wr->length long */
693         wr->type=type; /* not needed but helps for debugging */
694         wr->length+=SSL3_RT_HEADER_LENGTH;
695
696         if (create_empty_fragment)
697                 {
698                 /* we are in a recursive call;
699                  * just return the length, don't write out anything here
700                  */
701                 return wr->length;
702                 }
703
704         /* now let's set up wb */
705         wb->left = prefix_len + wr->length;
706         wb->offset = 0;
707
708         /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
709         s->s3->wpend_tot=len;
710         s->s3->wpend_buf=buf;
711         s->s3->wpend_type=type;
712         s->s3->wpend_ret=len;
713
714         /* we now just need to write the buffer */
715         return ssl3_write_pending(s,type,buf,len);
716 err:
717         return -1;
718         }
719
720 /* if s->s3->wbuf.left != 0, we need to call this */
721 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
722         unsigned int len)
723         {
724         int i;
725
726 /* XXXX */
727         if ((s->s3->wpend_tot > (int)len)
728                 || ((s->s3->wpend_buf != buf) &&
729                         !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
730                 || (s->s3->wpend_type != type))
731                 {
732                 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
733                 return(-1);
734                 }
735
736         for (;;)
737                 {
738                 clear_sys_error();
739                 if (s->wbio != NULL)
740                         {
741                         s->rwstate=SSL_WRITING;
742                         i=BIO_write(s->wbio,
743                                 (char *)&(s->s3->wbuf.buf[s->s3->wbuf.offset]),
744                                 (unsigned int)s->s3->wbuf.left);
745                         }
746                 else
747                         {
748                         SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
749                         i= -1;
750                         }
751                 if (i == s->s3->wbuf.left)
752                         {
753                         s->s3->wbuf.left=0;
754                         s->rwstate=SSL_NOTHING;
755                         return(s->s3->wpend_ret);
756                         }
757                 else if (i <= 0)
758                         return(i);
759                 s->s3->wbuf.offset+=i;
760                 s->s3->wbuf.left-=i;
761                 }
762         }
763
764 /* Return up to 'len' payload bytes received in 'type' records.
765  * 'type' is one of the following:
766  *
767  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
768  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
769  *   -  0 (during a shutdown, no data has to be returned)
770  *
771  * If we don't have stored data to work from, read a SSL/TLS record first
772  * (possibly multiple records if we still don't have anything to return).
773  *
774  * This function must handle any surprises the peer may have for us, such as
775  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
776  * a surprise, but handled as if it were), or renegotiation requests.
777  * Also if record payloads contain fragments too small to process, we store
778  * them until there is enough for the respective protocol (the record protocol
779  * may use arbitrary fragmentation and even interleaving):
780  *     Change cipher spec protocol
781  *             just 1 byte needed, no need for keeping anything stored
782  *     Alert protocol
783  *             2 bytes needed (AlertLevel, AlertDescription)
784  *     Handshake protocol
785  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
786  *             to detect unexpected Client Hello and Hello Request messages
787  *             here, anything else is handled by higher layers
788  *     Application data protocol
789  *             none of our business
790  */
791 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
792         {
793         int al,i,j,ret;
794         unsigned int n;
795         SSL3_RECORD *rr;
796         void (*cb)(const SSL *ssl,int type2,int val)=NULL;
797
798         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
799                 if (!ssl3_setup_buffers(s))
800                         return(-1);
801
802         if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) ||
803             (peek && (type != SSL3_RT_APPLICATION_DATA)))
804                 {
805                 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
806                 return -1;
807                 }
808
809         if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
810                 /* (partially) satisfy request from storage */
811                 {
812                 unsigned char *src = s->s3->handshake_fragment;
813                 unsigned char *dst = buf;
814                 unsigned int k;
815
816                 /* peek == 0 */
817                 n = 0;
818                 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
819                         {
820                         *dst++ = *src++;
821                         len--; s->s3->handshake_fragment_len--;
822                         n++;
823                         }
824                 /* move any remaining fragment bytes: */
825                 for (k = 0; k < s->s3->handshake_fragment_len; k++)
826                         s->s3->handshake_fragment[k] = *src++;
827                 return n;
828         }
829
830         /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
831
832         if (!s->in_handshake && SSL_in_init(s))
833                 {
834                 /* type == SSL3_RT_APPLICATION_DATA */
835                 i=s->handshake_func(s);
836                 if (i < 0) return(i);
837                 if (i == 0)
838                         {
839                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
840                         return(-1);
841                         }
842                 }
843 start:
844         s->rwstate=SSL_NOTHING;
845
846         /* s->s3->rrec.type         - is the type of record
847          * s->s3->rrec.data,    - data
848          * s->s3->rrec.off,     - offset into 'data' for next read
849          * s->s3->rrec.length,  - number of bytes. */
850         rr = &(s->s3->rrec);
851
852         /* get new packet if necessary */
853         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
854                 {
855                 ret=ssl3_get_record(s);
856                 if (ret <= 0) return(ret);
857                 }
858
859         /* we now have a packet which can be read and processed */
860
861         if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
862                                        * reset by ssl3_get_finished */
863                 && (rr->type != SSL3_RT_HANDSHAKE))
864                 {
865                 al=SSL_AD_UNEXPECTED_MESSAGE;
866                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
867                 goto f_err;
868                 }
869
870         /* If the other end has shut down, throw anything we read away
871          * (even in 'peek' mode) */
872         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
873                 {
874                 rr->length=0;
875                 s->rwstate=SSL_NOTHING;
876                 return(0);
877                 }
878
879
880         if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
881                 {
882                 /* make sure that we are not getting application data when we
883                  * are doing a handshake for the first time */
884                 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
885                         (s->enc_read_ctx == NULL))
886                         {
887                         al=SSL_AD_UNEXPECTED_MESSAGE;
888                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
889                         goto f_err;
890                         }
891
892                 if (len <= 0) return(len);
893
894                 if ((unsigned int)len > rr->length)
895                         n = rr->length;
896                 else
897                         n = (unsigned int)len;
898
899                 memcpy(buf,&(rr->data[rr->off]),n);
900                 if (!peek)
901                         {
902                         rr->length-=n;
903                         rr->off+=n;
904                         if (rr->length == 0)
905                                 {
906                                 s->rstate=SSL_ST_READ_HEADER;
907                                 rr->off=0;
908                                 }
909                         }
910                 return(n);
911                 }
912
913
914         /* If we get here, then type != rr->type; if we have a handshake
915          * message, then it was unexpected (Hello Request or Client Hello). */
916
917         /* In case of record types for which we have 'fragment' storage,
918          * fill that so that we can process the data at a fixed place.
919          */
920                 {
921                 unsigned int dest_maxlen = 0;
922                 unsigned char *dest = NULL;
923                 unsigned int *dest_len = NULL;
924
925                 if (rr->type == SSL3_RT_HANDSHAKE)
926                         {
927                         dest_maxlen = sizeof s->s3->handshake_fragment;
928                         dest = s->s3->handshake_fragment;
929                         dest_len = &s->s3->handshake_fragment_len;
930                         }
931                 else if (rr->type == SSL3_RT_ALERT)
932                         {
933                         dest_maxlen = sizeof s->s3->alert_fragment;
934                         dest = s->s3->alert_fragment;
935                         dest_len = &s->s3->alert_fragment_len;
936                         }
937
938                 if (dest_maxlen > 0)
939                         {
940                         n = dest_maxlen - *dest_len; /* available space in 'dest' */
941                         if (rr->length < n)
942                                 n = rr->length; /* available bytes */
943
944                         /* now move 'n' bytes: */
945                         while (n-- > 0)
946                                 {
947                                 dest[(*dest_len)++] = rr->data[rr->off++];
948                                 rr->length--;
949                                 }
950
951                         if (*dest_len < dest_maxlen)
952                                 goto start; /* fragment was too small */
953                         }
954                 }
955
956         /* s->s3->handshake_fragment_len == 4  iff  rr->type == SSL3_RT_HANDSHAKE;
957          * s->s3->alert_fragment_len == 2      iff  rr->type == SSL3_RT_ALERT.
958          * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
959
960         /* If we are a client, check for an incoming 'Hello Request': */
961         if ((!s->server) &&
962                 (s->s3->handshake_fragment_len >= 4) &&
963                 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
964                 (s->session != NULL) && (s->session->cipher != NULL))
965                 {
966                 s->s3->handshake_fragment_len = 0;
967
968                 if ((s->s3->handshake_fragment[1] != 0) ||
969                         (s->s3->handshake_fragment[2] != 0) ||
970                         (s->s3->handshake_fragment[3] != 0))
971                         {
972                         al=SSL_AD_DECODE_ERROR;
973                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
974                         goto f_err;
975                         }
976
977                 if (s->msg_callback)
978                         s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
979
980                 if (SSL_is_init_finished(s) &&
981                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
982                         !s->s3->renegotiate)
983                         {
984                         ssl3_renegotiate(s);
985                         if (ssl3_renegotiate_check(s))
986                                 {
987                                 i=s->handshake_func(s);
988                                 if (i < 0) return(i);
989                                 if (i == 0)
990                                         {
991                                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
992                                         return(-1);
993                                         }
994
995                                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
996                                         {
997                                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
998                                                 {
999                                                 BIO *bio;
1000                                                 /* In the case where we try to read application data,
1001                                                  * but we trigger an SSL handshake, we return -1 with
1002                                                  * the retry option set.  Otherwise renegotiation may
1003                                                  * cause nasty problems in the blocking world */
1004                                                 s->rwstate=SSL_READING;
1005                                                 bio=SSL_get_rbio(s);
1006                                                 BIO_clear_retry_flags(bio);
1007                                                 BIO_set_retry_read(bio);
1008                                                 return(-1);
1009                                                 }
1010                                         }
1011                                 }
1012                         }
1013                 /* we either finished a handshake or ignored the request,
1014                  * now try again to obtain the (application) data we were asked for */
1015                 goto start;
1016                 }
1017
1018         if (s->s3->alert_fragment_len >= 2)
1019                 {
1020                 int alert_level = s->s3->alert_fragment[0];
1021                 int alert_descr = s->s3->alert_fragment[1];
1022
1023                 s->s3->alert_fragment_len = 0;
1024
1025                 if (s->msg_callback)
1026                         s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1027
1028                 if (s->info_callback != NULL)
1029                         cb=s->info_callback;
1030                 else if (s->ctx->info_callback != NULL)
1031                         cb=s->ctx->info_callback;
1032
1033                 if (cb != NULL)
1034                         {
1035                         j = (alert_level << 8) | alert_descr;
1036                         cb(s, SSL_CB_READ_ALERT, j);
1037                         }
1038
1039                 if (alert_level == 1) /* warning */
1040                         {
1041                         s->s3->warn_alert = alert_descr;
1042                         if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1043                                 {
1044                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1045                                 return(0);
1046                                 }
1047                         }
1048                 else if (alert_level == 2) /* fatal */
1049                         {
1050                         char tmp[16];
1051
1052                         s->rwstate=SSL_NOTHING;
1053                         s->s3->fatal_alert = alert_descr;
1054                         SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1055                         BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1056                         ERR_add_error_data(2,"SSL alert number ",tmp);
1057                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1058                         SSL_CTX_remove_session(s->ctx,s->session);
1059                         return(0);
1060                         }
1061                 else
1062                         {
1063                         al=SSL_AD_ILLEGAL_PARAMETER;
1064                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1065                         goto f_err;
1066                         }
1067
1068                 goto start;
1069                 }
1070
1071         if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1072                 {
1073                 s->rwstate=SSL_NOTHING;
1074                 rr->length=0;
1075                 return(0);
1076                 }
1077
1078         if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1079                 {
1080                 /* 'Change Cipher Spec' is just a single byte, so we know
1081                  * exactly what the record payload has to look like */
1082                 if (    (rr->length != 1) || (rr->off != 0) ||
1083                         (rr->data[0] != SSL3_MT_CCS))
1084                         {
1085                         al=SSL_AD_ILLEGAL_PARAMETER;
1086                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1087                         goto f_err;
1088                         }
1089
1090                 /* Check we have a cipher to change to */
1091                 if (s->s3->tmp.new_cipher == NULL)
1092                         {
1093                         al=SSL_AD_UNEXPECTED_MESSAGE;
1094                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1095                         goto f_err;
1096                         }
1097
1098                 rr->length=0;
1099
1100                 if (s->msg_callback)
1101                         s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1102
1103                 s->s3->change_cipher_spec=1;
1104                 if (!ssl3_do_change_cipher_spec(s))
1105                         goto err;
1106                 else
1107                         goto start;
1108                 }
1109
1110         /* Unexpected handshake message (Client Hello, or protocol violation) */
1111         if ((s->s3->handshake_fragment_len >= 4) &&     !s->in_handshake)
1112                 {
1113                 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1114                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1115                         {
1116 #if 0 /* worked only because C operator preferences are not as expected (and
1117        * because this is not really needed for clients except for detecting
1118        * protocol violations): */
1119                         s->state=SSL_ST_BEFORE|(s->server)
1120                                 ?SSL_ST_ACCEPT
1121                                 :SSL_ST_CONNECT;
1122 #else
1123                         s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1124 #endif
1125                         s->new_session=1;
1126                         }
1127                 i=s->handshake_func(s);
1128                 if (i < 0) return(i);
1129                 if (i == 0)
1130                         {
1131                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1132                         return(-1);
1133                         }
1134
1135                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1136                         {
1137                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1138                                 {
1139                                 BIO *bio;
1140                                 /* In the case where we try to read application data,
1141                                  * but we trigger an SSL handshake, we return -1 with
1142                                  * the retry option set.  Otherwise renegotiation may
1143                                  * cause nasty problems in the blocking world */
1144                                 s->rwstate=SSL_READING;
1145                                 bio=SSL_get_rbio(s);
1146                                 BIO_clear_retry_flags(bio);
1147                                 BIO_set_retry_read(bio);
1148                                 return(-1);
1149                                 }
1150                         }
1151                 goto start;
1152                 }
1153
1154         switch (rr->type)
1155                 {
1156         default:
1157 #ifndef OPENSSL_NO_TLS
1158                 /* TLS just ignores unknown message types */
1159                 if (s->version == TLS1_VERSION)
1160                         {
1161                         rr->length = 0;
1162                         goto start;
1163                         }
1164 #endif
1165                 al=SSL_AD_UNEXPECTED_MESSAGE;
1166                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1167                 goto f_err;
1168         case SSL3_RT_CHANGE_CIPHER_SPEC:
1169         case SSL3_RT_ALERT:
1170         case SSL3_RT_HANDSHAKE:
1171                 /* we already handled all of these, with the possible exception
1172                  * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1173                  * should not happen when type != rr->type */
1174                 al=SSL_AD_UNEXPECTED_MESSAGE;
1175                 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1176                 goto f_err;
1177         case SSL3_RT_APPLICATION_DATA:
1178                 /* At this point, we were expecting handshake data,
1179                  * but have application data.  If the library was
1180                  * running inside ssl3_read() (i.e. in_read_app_data
1181                  * is set) and it makes sense to read application data
1182                  * at this point (session renegotiation not yet started),
1183                  * we will indulge it.
1184                  */
1185                 if (s->s3->in_read_app_data &&
1186                         (s->s3->total_renegotiations != 0) &&
1187                         ((
1188                                 (s->state & SSL_ST_CONNECT) &&
1189                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1190                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1191                                 ) || (
1192                                         (s->state & SSL_ST_ACCEPT) &&
1193                                         (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1194                                         (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1195                                         )
1196                                 ))
1197                         {
1198                         s->s3->in_read_app_data=2;
1199                         return(-1);
1200                         }
1201                 else
1202                         {
1203                         al=SSL_AD_UNEXPECTED_MESSAGE;
1204                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1205                         goto f_err;
1206                         }
1207                 }
1208         /* not reached */
1209
1210 f_err:
1211         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1212 err:
1213         return(-1);
1214         }
1215
1216 int ssl3_do_change_cipher_spec(SSL *s)
1217         {
1218         int i;
1219         const char *sender;
1220         int slen;
1221
1222         if (s->state & SSL_ST_ACCEPT)
1223                 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1224         else
1225                 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1226
1227         if (s->s3->tmp.key_block == NULL)
1228                 {
1229                 s->session->cipher=s->s3->tmp.new_cipher;
1230                 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1231                 }
1232
1233         if (!s->method->ssl3_enc->change_cipher_state(s,i))
1234                 return(0);
1235
1236         /* we have to record the message digest at
1237          * this point so we can get it before we read
1238          * the finished message */
1239         if (s->state & SSL_ST_CONNECT)
1240                 {
1241                 sender=s->method->ssl3_enc->server_finished_label;
1242                 slen=s->method->ssl3_enc->server_finished_label_len;
1243                 }
1244         else
1245                 {
1246                 sender=s->method->ssl3_enc->client_finished_label;
1247                 slen=s->method->ssl3_enc->client_finished_label_len;
1248                 }
1249
1250         s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1251                 &(s->s3->finish_dgst1),
1252                 &(s->s3->finish_dgst2),
1253                 sender,slen,s->s3->tmp.peer_finish_md);
1254
1255         return(1);
1256         }
1257
1258 void ssl3_send_alert(SSL *s, int level, int desc)
1259         {
1260         /* Map tls/ssl alert value to correct one */
1261         desc=s->method->ssl3_enc->alert_value(desc);
1262         if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1263                 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1264         if (desc < 0) return;
1265         /* If a fatal one, remove from cache */
1266         if ((level == 2) && (s->session != NULL))
1267                 SSL_CTX_remove_session(s->ctx,s->session);
1268
1269         s->s3->alert_dispatch=1;
1270         s->s3->send_alert[0]=level;
1271         s->s3->send_alert[1]=desc;
1272         if (s->s3->wbuf.left == 0) /* data still being written out? */
1273                 s->method->ssl_dispatch_alert(s);
1274         /* else data is still being written out, we will get written
1275          * some time in the future */
1276         }
1277
1278 int ssl3_dispatch_alert(SSL *s)
1279         {
1280         int i,j;
1281         void (*cb)(const SSL *ssl,int type,int val)=NULL;
1282
1283         s->s3->alert_dispatch=0;
1284         i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1285         if (i <= 0)
1286                 {
1287                 s->s3->alert_dispatch=1;
1288                 }
1289         else
1290                 {
1291                 /* Alert sent to BIO.  If it is important, flush it now.
1292                  * If the message does not get sent due to non-blocking IO,
1293                  * we will not worry too much. */
1294                 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1295                         (void)BIO_flush(s->wbio);
1296
1297                 if (s->msg_callback)
1298                         s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1299
1300                 if (s->info_callback != NULL)
1301                         cb=s->info_callback;
1302                 else if (s->ctx->info_callback != NULL)
1303                         cb=s->ctx->info_callback;
1304
1305                 if (cb != NULL)
1306                         {
1307                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1308                         cb(s,SSL_CB_WRITE_ALERT,j);
1309                         }
1310                 }
1311         return(i);
1312         }