fc913c2d9e69b96ba02fef7b3015c9f547afc8c3
[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->init_extra)
254                 {
255                 /* 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 #if 0
279 fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length);
280 #endif
281
282                 /* Lets check version */
283                 if (s->first_packet)
284                         {
285                         s->first_packet=0;
286                         }
287                 else
288                         {
289                         if (version != s->version)
290                                 {
291                                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
292                                 /* Send back error using their
293                                  * version number :-) */
294                                 s->version=version;
295                                 al=SSL_AD_PROTOCOL_VERSION;
296                                 goto f_err;
297                                 }
298                         }
299
300                 if ((version>>8) != SSL3_VERSION_MAJOR)
301                         {
302                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
303                         goto err;
304                         }
305
306                 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH)
307                         {
308                         al=SSL_AD_RECORD_OVERFLOW;
309                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
310                         goto f_err;
311                         }
312
313                 /* now s->rstate == SSL_ST_READ_BODY */
314                 }
315
316         /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
317
318         if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
319                 {
320                 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
321                 i=rr->length;
322                 n=ssl3_read_n(s,i,i,1);
323                 if (n <= 0) return(n); /* error or non-blocking io */
324                 /* now n == rr->length,
325                  * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
326                 }
327
328         s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
329
330         /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
331          * and we have that many bytes in s->packet
332          */
333         rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
334
335         /* ok, we can now read from 's->packet' data into 'rr'
336          * rr->input points at rr->length bytes, which
337          * need to be copied into rr->data by either
338          * the decryption or by the decompression
339          * When the data is 'copied' into the rr->data buffer,
340          * rr->input will be pointed at the new buffer */ 
341
342         /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
343          * rr->length bytes of encrypted compressed stuff. */
344
345         /* check is not needed I believe */
346         if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
347                 {
348                 al=SSL_AD_RECORD_OVERFLOW;
349                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
350                 goto f_err;
351                 }
352
353         /* decrypt in place in 'rr->input' */
354         rr->data=rr->input;
355
356         enc_err = s->method->ssl3_enc->enc(s,0);
357         if (enc_err <= 0)
358                 {
359                 if (enc_err == 0)
360                         /* SSLerr() and ssl3_send_alert() have been called */
361                         goto err;
362
363                 /* Otherwise enc_err == -1, which indicates bad padding
364                  * (rec->length has not been changed in this case).
365                  * To minimize information leaked via timing, we will perform
366                  * the MAC computation anyway. */
367                 decryption_failed_or_bad_record_mac = 1;
368                 }
369
370 #ifdef TLS_DEBUG
371 printf("dec %d\n",rr->length);
372 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
373 printf("\n");
374 #endif
375
376         /* r->length is now the compressed data plus mac */
377         if (    (sess == NULL) ||
378                 (s->enc_read_ctx == NULL) ||
379                 (s->read_hash == NULL))
380                 clear=1;
381
382         if (!clear)
383                 {
384                 mac_size=EVP_MD_size(s->read_hash);
385
386                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
387                         {
388 #if 0 /* OK only for stream ciphers (then rr->length is visible from ciphertext anyway) */
389                         al=SSL_AD_RECORD_OVERFLOW;
390                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG);
391                         goto f_err;
392 #else
393                         decryption_failed_or_bad_record_mac = 1;
394 #endif                  
395                         }
396                 /* check the MAC for rr->input (it's in mac_size bytes at the tail) */
397                 if (rr->length >= mac_size)
398                         {
399                         rr->length -= mac_size;
400                         mac = &rr->data[rr->length];
401                         }
402                 else
403                         {
404                         /* record (minus padding) is too short to contain a MAC */
405 #if 0 /* OK only for stream ciphers */
406                         al=SSL_AD_DECODE_ERROR;
407                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
408                         goto f_err;
409 #else
410                         decryption_failed_or_bad_record_mac = 1;
411                         rr->length = 0;
412 #endif
413                         }
414                 i=s->method->ssl3_enc->mac(s,md,0);
415                 if (mac == NULL || memcmp(md, mac, mac_size) != 0)
416                         {
417                         decryption_failed_or_bad_record_mac = 1;
418                         }
419                 }
420
421         if (decryption_failed_or_bad_record_mac)
422                 {
423                 /* A separate 'decryption_failed' alert was introduced with TLS 1.0,
424                  * SSL 3.0 only has 'bad_record_mac'.  But unless a decryption
425                  * failure is directly visible from the ciphertext anyway,
426                  * we should not reveal which kind of error occured -- this
427                  * might become visible to an attacker (e.g. via a logfile) */
428                 al=SSL_AD_BAD_RECORD_MAC;
429                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
430                 goto f_err;
431                 }
432
433         /* r->length is now just compressed */
434         if (s->expand != NULL)
435                 {
436                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
437                         {
438                         al=SSL_AD_RECORD_OVERFLOW;
439                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
440                         goto f_err;
441                         }
442                 if (!ssl3_do_uncompress(s))
443                         {
444                         al=SSL_AD_DECOMPRESSION_FAILURE;
445                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
446                         goto f_err;
447                         }
448                 }
449
450         if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
451                 {
452                 al=SSL_AD_RECORD_OVERFLOW;
453                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
454                 goto f_err;
455                 }
456
457         rr->off=0;
458         /* So at this point the following is true
459          * ssl->s3->rrec.type   is the type of record
460          * ssl->s3->rrec.length == number of bytes in record
461          * ssl->s3->rrec.off    == offset to first valid byte
462          * ssl->s3->rrec.data   == where to take bytes from, increment
463          *                         after use :-).
464          */
465
466         /* we have pulled in a full packet so zero things */
467         s->packet_length=0;
468
469         /* just read a 0 length packet */
470         if (rr->length == 0) goto again;
471
472 #if 0
473 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length);
474 #endif
475
476         return(1);
477
478 f_err:
479         ssl3_send_alert(s,SSL3_AL_FATAL,al);
480 err:
481         return(ret);
482         }
483
484 int ssl3_do_uncompress(SSL *ssl)
485         {
486 #ifndef OPENSSL_NO_COMP
487         int i;
488         SSL3_RECORD *rr;
489
490         rr= &(ssl->s3->rrec);
491         i=COMP_expand_block(ssl->expand,rr->comp,
492                 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
493         if (i < 0)
494                 return(0);
495         else
496                 rr->length=i;
497         rr->data=rr->comp;
498 #endif
499         return(1);
500         }
501
502 int ssl3_do_compress(SSL *ssl)
503         {
504 #ifndef OPENSSL_NO_COMP
505         int i;
506         SSL3_RECORD *wr;
507
508         wr= &(ssl->s3->wrec);
509         i=COMP_compress_block(ssl->compress,wr->data,
510                 SSL3_RT_MAX_COMPRESSED_LENGTH,
511                 wr->input,(int)wr->length);
512         if (i < 0)
513                 return(0);
514         else
515                 wr->length=i;
516
517         wr->input=wr->data;
518 #endif
519         return(1);
520         }
521
522 /* Call this to write data in records of type 'type'
523  * It will return <= 0 if not all data has been sent or non-blocking IO.
524  */
525 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
526         {
527         const unsigned char *buf=buf_;
528         unsigned int tot,n,nw;
529         int i;
530
531         s->rwstate=SSL_NOTHING;
532         tot=s->s3->wnum;
533         s->s3->wnum=0;
534
535         if (SSL_in_init(s) && !s->in_handshake)
536                 {
537                 i=s->handshake_func(s);
538                 if (i < 0) return(i);
539                 if (i == 0)
540                         {
541                         SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
542                         return -1;
543                         }
544                 }
545
546         n=(len-tot);
547         for (;;)
548                 {
549                 if (n > s->max_send_fragment)
550                         nw=s->max_send_fragment;
551                 else
552                         nw=n;
553
554                 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
555                 if (i <= 0)
556                         {
557                         s->s3->wnum=tot;
558                         return i;
559                         }
560
561                 if ((i == (int)n) ||
562                         (type == SSL3_RT_APPLICATION_DATA &&
563                          (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
564                         {
565                         /* next chunk of data should get another prepended empty fragment
566                          * in ciphersuites with known-IV weakness: */
567                         s->s3->empty_fragment_done = 0;
568                         
569                         return tot+i;
570                         }
571
572                 n-=i;
573                 tot+=i;
574                 }
575         }
576
577 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
578                          unsigned int len, int create_empty_fragment)
579         {
580         unsigned char *p,*plen;
581         int i,mac_size,clear=0;
582         int prefix_len = 0;
583         SSL3_RECORD *wr;
584         SSL3_BUFFER *wb;
585         SSL_SESSION *sess;
586
587         /* first check if there is a SSL3_BUFFER still being written
588          * out.  This will happen with non blocking IO */
589         if (s->s3->wbuf.left != 0)
590                 return(ssl3_write_pending(s,type,buf,len));
591
592         /* If we have an alert to send, lets send it */
593         if (s->s3->alert_dispatch)
594                 {
595                 i=s->method->ssl_dispatch_alert(s);
596                 if (i <= 0)
597                         return(i);
598                 /* if it went, fall through and send more stuff */
599                 }
600
601         if (len == 0 && !create_empty_fragment)
602                 return 0;
603
604         wr= &(s->s3->wrec);
605         wb= &(s->s3->wbuf);
606         sess=s->session;
607
608         if (    (sess == NULL) ||
609                 (s->enc_write_ctx == NULL) ||
610                 (s->write_hash == NULL))
611                 clear=1;
612
613         if (clear)
614                 mac_size=0;
615         else
616                 mac_size=EVP_MD_size(s->write_hash);
617
618         /* 'create_empty_fragment' is true only when this function calls itself */
619         if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
620                 {
621                 /* countermeasure against known-IV weakness in CBC ciphersuites
622                  * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
623
624                 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
625                         {
626                         /* recursive function call with 'create_empty_fragment' set;
627                          * this prepares and buffers the data for an empty fragment
628                          * (these 'prefix_len' bytes are sent out later
629                          * together with the actual payload) */
630                         prefix_len = do_ssl3_write(s, type, buf, 0, 1);
631                         if (prefix_len <= 0)
632                                 goto err;
633
634                         if (prefix_len >
635                 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD))
636                                 {
637                                 /* insufficient space */
638                                 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
639                                 goto err;
640                                 }
641                         }
642                 
643                 s->s3->empty_fragment_done = 1;
644                 }
645
646         p = wb->buf + prefix_len;
647
648         /* write the header */
649
650         *(p++)=type&0xff;
651         wr->type=type;
652
653         *(p++)=(s->version>>8);
654         *(p++)=s->version&0xff;
655
656         /* field where we are to write out packet length */
657         plen=p; 
658         p+=2;
659
660         /* lets setup the record stuff. */
661         wr->data=p;
662         wr->length=(int)len;
663         wr->input=(unsigned char *)buf;
664
665         /* we now 'read' from wr->input, wr->length bytes into
666          * wr->data */
667
668         /* first we compress */
669         if (s->compress != NULL)
670                 {
671                 if (!ssl3_do_compress(s))
672                         {
673                         SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
674                         goto err;
675                         }
676                 }
677         else
678                 {
679                 memcpy(wr->data,wr->input,wr->length);
680                 wr->input=wr->data;
681                 }
682
683         /* we should still have the output to wr->data and the input
684          * from wr->input.  Length should be wr->length.
685          * wr->data still points in the wb->buf */
686
687         if (mac_size != 0)
688                 {
689                 s->method->ssl3_enc->mac(s,&(p[wr->length]),1);
690                 wr->length+=mac_size;
691                 wr->input=p;
692                 wr->data=p;
693                 }
694
695         /* ssl3_enc can only have an error on read */
696         s->method->ssl3_enc->enc(s,1);
697
698         /* record length after mac and block padding */
699         s2n(wr->length,plen);
700
701         /* we should now have
702          * wr->data pointing to the encrypted data, which is
703          * wr->length long */
704         wr->type=type; /* not needed but helps for debugging */
705         wr->length+=SSL3_RT_HEADER_LENGTH;
706
707         if (create_empty_fragment)
708                 {
709                 /* we are in a recursive call;
710                  * just return the length, don't write out anything here
711                  */
712                 return wr->length;
713                 }
714
715         /* now let's set up wb */
716         wb->left = prefix_len + wr->length;
717         wb->offset = 0;
718
719         /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
720         s->s3->wpend_tot=len;
721         s->s3->wpend_buf=buf;
722         s->s3->wpend_type=type;
723         s->s3->wpend_ret=len;
724
725         /* we now just need to write the buffer */
726         return ssl3_write_pending(s,type,buf,len);
727 err:
728         return -1;
729         }
730
731 /* if s->s3->wbuf.left != 0, we need to call this */
732 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
733         unsigned int len)
734         {
735         int i;
736
737 /* XXXX */
738         if ((s->s3->wpend_tot > (int)len)
739                 || ((s->s3->wpend_buf != buf) &&
740                         !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
741                 || (s->s3->wpend_type != type))
742                 {
743                 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
744                 return(-1);
745                 }
746
747         for (;;)
748                 {
749                 clear_sys_error();
750                 if (s->wbio != NULL)
751                         {
752                         s->rwstate=SSL_WRITING;
753                         i=BIO_write(s->wbio,
754                                 (char *)&(s->s3->wbuf.buf[s->s3->wbuf.offset]),
755                                 (unsigned int)s->s3->wbuf.left);
756                         }
757                 else
758                         {
759                         SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
760                         i= -1;
761                         }
762                 if (i == s->s3->wbuf.left)
763                         {
764                         s->s3->wbuf.left=0;
765                         s->rwstate=SSL_NOTHING;
766                         return(s->s3->wpend_ret);
767                         }
768                 else if (i <= 0)
769                         return(i);
770                 s->s3->wbuf.offset+=i;
771                 s->s3->wbuf.left-=i;
772                 }
773         }
774
775 /* Return up to 'len' payload bytes received in 'type' records.
776  * 'type' is one of the following:
777  *
778  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
779  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
780  *   -  0 (during a shutdown, no data has to be returned)
781  *
782  * If we don't have stored data to work from, read a SSL/TLS record first
783  * (possibly multiple records if we still don't have anything to return).
784  *
785  * This function must handle any surprises the peer may have for us, such as
786  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
787  * a surprise, but handled as if it were), or renegotiation requests.
788  * Also if record payloads contain fragments too small to process, we store
789  * them until there is enough for the respective protocol (the record protocol
790  * may use arbitrary fragmentation and even interleaving):
791  *     Change cipher spec protocol
792  *             just 1 byte needed, no need for keeping anything stored
793  *     Alert protocol
794  *             2 bytes needed (AlertLevel, AlertDescription)
795  *     Handshake protocol
796  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
797  *             to detect unexpected Client Hello and Hello Request messages
798  *             here, anything else is handled by higher layers
799  *     Application data protocol
800  *             none of our business
801  */
802 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
803         {
804         int al,i,j,ret;
805         unsigned int n;
806         SSL3_RECORD *rr;
807         void (*cb)(const SSL *ssl,int type2,int val)=NULL;
808
809         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
810                 if (!ssl3_setup_buffers(s))
811                         return(-1);
812
813         if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) ||
814             (peek && (type != SSL3_RT_APPLICATION_DATA)))
815                 {
816                 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
817                 return -1;
818                 }
819
820         if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
821                 /* (partially) satisfy request from storage */
822                 {
823                 unsigned char *src = s->s3->handshake_fragment;
824                 unsigned char *dst = buf;
825                 unsigned int k;
826
827                 /* peek == 0 */
828                 n = 0;
829                 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
830                         {
831                         *dst++ = *src++;
832                         len--; s->s3->handshake_fragment_len--;
833                         n++;
834                         }
835                 /* move any remaining fragment bytes: */
836                 for (k = 0; k < s->s3->handshake_fragment_len; k++)
837                         s->s3->handshake_fragment[k] = *src++;
838                 return n;
839         }
840
841         /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
842
843         if (!s->in_handshake && SSL_in_init(s))
844                 {
845                 /* type == SSL3_RT_APPLICATION_DATA */
846                 i=s->handshake_func(s);
847                 if (i < 0) return(i);
848                 if (i == 0)
849                         {
850                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
851                         return(-1);
852                         }
853                 }
854 start:
855         s->rwstate=SSL_NOTHING;
856
857         /* s->s3->rrec.type         - is the type of record
858          * s->s3->rrec.data,    - data
859          * s->s3->rrec.off,     - offset into 'data' for next read
860          * s->s3->rrec.length,  - number of bytes. */
861         rr = &(s->s3->rrec);
862
863         /* get new packet if necessary */
864         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
865                 {
866                 ret=ssl3_get_record(s);
867                 if (ret <= 0) return(ret);
868                 }
869
870         /* we now have a packet which can be read and processed */
871
872         if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
873                                        * reset by ssl3_get_finished */
874                 && (rr->type != SSL3_RT_HANDSHAKE))
875                 {
876                 al=SSL_AD_UNEXPECTED_MESSAGE;
877                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
878                 goto f_err;
879                 }
880
881         /* If the other end has shut down, throw anything we read away
882          * (even in 'peek' mode) */
883         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
884                 {
885                 rr->length=0;
886                 s->rwstate=SSL_NOTHING;
887                 return(0);
888                 }
889
890
891         if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
892                 {
893                 /* make sure that we are not getting application data when we
894                  * are doing a handshake for the first time */
895                 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
896                         (s->enc_read_ctx == NULL))
897                         {
898                         al=SSL_AD_UNEXPECTED_MESSAGE;
899                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
900                         goto f_err;
901                         }
902
903                 if (len <= 0) return(len);
904
905                 if ((unsigned int)len > rr->length)
906                         n = rr->length;
907                 else
908                         n = (unsigned int)len;
909
910                 memcpy(buf,&(rr->data[rr->off]),n);
911                 if (!peek)
912                         {
913                         rr->length-=n;
914                         rr->off+=n;
915                         if (rr->length == 0)
916                                 {
917                                 s->rstate=SSL_ST_READ_HEADER;
918                                 rr->off=0;
919                                 }
920                         }
921                 return(n);
922                 }
923
924
925         /* If we get here, then type != rr->type; if we have a handshake
926          * message, then it was unexpected (Hello Request or Client Hello). */
927
928         /* In case of record types for which we have 'fragment' storage,
929          * fill that so that we can process the data at a fixed place.
930          */
931                 {
932                 unsigned int dest_maxlen = 0;
933                 unsigned char *dest = NULL;
934                 unsigned int *dest_len = NULL;
935
936                 if (rr->type == SSL3_RT_HANDSHAKE)
937                         {
938                         dest_maxlen = sizeof s->s3->handshake_fragment;
939                         dest = s->s3->handshake_fragment;
940                         dest_len = &s->s3->handshake_fragment_len;
941                         }
942                 else if (rr->type == SSL3_RT_ALERT)
943                         {
944                         dest_maxlen = sizeof s->s3->alert_fragment;
945                         dest = s->s3->alert_fragment;
946                         dest_len = &s->s3->alert_fragment_len;
947                         }
948
949                 if (dest_maxlen > 0)
950                         {
951                         n = dest_maxlen - *dest_len; /* available space in 'dest' */
952                         if (rr->length < n)
953                                 n = rr->length; /* available bytes */
954
955                         /* now move 'n' bytes: */
956                         while (n-- > 0)
957                                 {
958                                 dest[(*dest_len)++] = rr->data[rr->off++];
959                                 rr->length--;
960                                 }
961
962                         if (*dest_len < dest_maxlen)
963                                 goto start; /* fragment was too small */
964                         }
965                 }
966
967         /* s->s3->handshake_fragment_len == 4  iff  rr->type == SSL3_RT_HANDSHAKE;
968          * s->s3->alert_fragment_len == 2      iff  rr->type == SSL3_RT_ALERT.
969          * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
970
971         /* If we are a client, check for an incoming 'Hello Request': */
972         if ((!s->server) &&
973                 (s->s3->handshake_fragment_len >= 4) &&
974                 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
975                 (s->session != NULL) && (s->session->cipher != NULL))
976                 {
977                 s->s3->handshake_fragment_len = 0;
978
979                 if ((s->s3->handshake_fragment[1] != 0) ||
980                         (s->s3->handshake_fragment[2] != 0) ||
981                         (s->s3->handshake_fragment[3] != 0))
982                         {
983                         al=SSL_AD_DECODE_ERROR;
984                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
985                         goto f_err;
986                         }
987
988                 if (s->msg_callback)
989                         s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
990
991                 if (SSL_is_init_finished(s) &&
992                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
993                         !s->s3->renegotiate)
994                         {
995                         ssl3_renegotiate(s);
996                         if (ssl3_renegotiate_check(s))
997                                 {
998                                 i=s->handshake_func(s);
999                                 if (i < 0) return(i);
1000                                 if (i == 0)
1001                                         {
1002                                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1003                                         return(-1);
1004                                         }
1005
1006                                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1007                                         {
1008                                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1009                                                 {
1010                                                 BIO *bio;
1011                                                 /* In the case where we try to read application data,
1012                                                  * but we trigger an SSL handshake, we return -1 with
1013                                                  * the retry option set.  Otherwise renegotiation may
1014                                                  * cause nasty problems in the blocking world */
1015                                                 s->rwstate=SSL_READING;
1016                                                 bio=SSL_get_rbio(s);
1017                                                 BIO_clear_retry_flags(bio);
1018                                                 BIO_set_retry_read(bio);
1019                                                 return(-1);
1020                                                 }
1021                                         }
1022                                 }
1023                         }
1024                 /* we either finished a handshake or ignored the request,
1025                  * now try again to obtain the (application) data we were asked for */
1026                 goto start;
1027                 }
1028
1029         if (s->s3->alert_fragment_len >= 2)
1030                 {
1031                 int alert_level = s->s3->alert_fragment[0];
1032                 int alert_descr = s->s3->alert_fragment[1];
1033
1034                 s->s3->alert_fragment_len = 0;
1035
1036                 if (s->msg_callback)
1037                         s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1038
1039                 if (s->info_callback != NULL)
1040                         cb=s->info_callback;
1041                 else if (s->ctx->info_callback != NULL)
1042                         cb=s->ctx->info_callback;
1043
1044                 if (cb != NULL)
1045                         {
1046                         j = (alert_level << 8) | alert_descr;
1047                         cb(s, SSL_CB_READ_ALERT, j);
1048                         }
1049
1050                 if (alert_level == 1) /* warning */
1051                         {
1052                         s->s3->warn_alert = alert_descr;
1053                         if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1054                                 {
1055                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1056                                 return(0);
1057                                 }
1058                         }
1059                 else if (alert_level == 2) /* fatal */
1060                         {
1061                         char tmp[16];
1062
1063                         s->rwstate=SSL_NOTHING;
1064                         s->s3->fatal_alert = alert_descr;
1065                         SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1066                         BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1067                         ERR_add_error_data(2,"SSL alert number ",tmp);
1068                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1069                         SSL_CTX_remove_session(s->ctx,s->session);
1070                         return(0);
1071                         }
1072                 else
1073                         {
1074                         al=SSL_AD_ILLEGAL_PARAMETER;
1075                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1076                         goto f_err;
1077                         }
1078
1079                 goto start;
1080                 }
1081
1082         if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1083                 {
1084                 s->rwstate=SSL_NOTHING;
1085                 rr->length=0;
1086                 return(0);
1087                 }
1088
1089         if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1090                 {
1091                 /* 'Change Cipher Spec' is just a single byte, so we know
1092                  * exactly what the record payload has to look like */
1093                 if (    (rr->length != 1) || (rr->off != 0) ||
1094                         (rr->data[0] != SSL3_MT_CCS))
1095                         {
1096                         al=SSL_AD_ILLEGAL_PARAMETER;
1097                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1098                         goto f_err;
1099                         }
1100
1101                 /* Check we have a cipher to change to */
1102                 if (s->s3->tmp.new_cipher == NULL)
1103                         {
1104                         al=SSL_AD_UNEXPECTED_MESSAGE;
1105                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1106                         goto f_err;
1107                         }
1108
1109                 rr->length=0;
1110
1111                 if (s->msg_callback)
1112                         s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1113
1114                 s->s3->change_cipher_spec=1;
1115                 if (!ssl3_do_change_cipher_spec(s))
1116                         goto err;
1117                 else
1118                         goto start;
1119                 }
1120
1121         /* Unexpected handshake message (Client Hello, or protocol violation) */
1122         if ((s->s3->handshake_fragment_len >= 4) &&     !s->in_handshake)
1123                 {
1124                 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1125                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1126                         {
1127 #if 0 /* worked only because C operator preferences are not as expected (and
1128        * because this is not really needed for clients except for detecting
1129        * protocol violations): */
1130                         s->state=SSL_ST_BEFORE|(s->server)
1131                                 ?SSL_ST_ACCEPT
1132                                 :SSL_ST_CONNECT;
1133 #else
1134                         s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1135 #endif
1136                         s->new_session=1;
1137                         }
1138                 i=s->handshake_func(s);
1139                 if (i < 0) return(i);
1140                 if (i == 0)
1141                         {
1142                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1143                         return(-1);
1144                         }
1145
1146                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1147                         {
1148                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1149                                 {
1150                                 BIO *bio;
1151                                 /* In the case where we try to read application data,
1152                                  * but we trigger an SSL handshake, we return -1 with
1153                                  * the retry option set.  Otherwise renegotiation may
1154                                  * cause nasty problems in the blocking world */
1155                                 s->rwstate=SSL_READING;
1156                                 bio=SSL_get_rbio(s);
1157                                 BIO_clear_retry_flags(bio);
1158                                 BIO_set_retry_read(bio);
1159                                 return(-1);
1160                                 }
1161                         }
1162                 goto start;
1163                 }
1164
1165         switch (rr->type)
1166                 {
1167         default:
1168 #ifndef OPENSSL_NO_TLS
1169                 /* TLS just ignores unknown message types */
1170                 if (s->version == TLS1_VERSION)
1171                         {
1172                         rr->length = 0;
1173                         goto start;
1174                         }
1175 #endif
1176                 al=SSL_AD_UNEXPECTED_MESSAGE;
1177                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1178                 goto f_err;
1179         case SSL3_RT_CHANGE_CIPHER_SPEC:
1180         case SSL3_RT_ALERT:
1181         case SSL3_RT_HANDSHAKE:
1182                 /* we already handled all of these, with the possible exception
1183                  * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1184                  * should not happen when type != rr->type */
1185                 al=SSL_AD_UNEXPECTED_MESSAGE;
1186                 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1187                 goto f_err;
1188         case SSL3_RT_APPLICATION_DATA:
1189                 /* At this point, we were expecting handshake data,
1190                  * but have application data.  If the library was
1191                  * running inside ssl3_read() (i.e. in_read_app_data
1192                  * is set) and it makes sense to read application data
1193                  * at this point (session renegotiation not yet started),
1194                  * we will indulge it.
1195                  */
1196                 if (s->s3->in_read_app_data &&
1197                         (s->s3->total_renegotiations != 0) &&
1198                         ((
1199                                 (s->state & SSL_ST_CONNECT) &&
1200                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1201                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1202                                 ) || (
1203                                         (s->state & SSL_ST_ACCEPT) &&
1204                                         (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1205                                         (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1206                                         )
1207                                 ))
1208                         {
1209                         s->s3->in_read_app_data=2;
1210                         return(-1);
1211                         }
1212                 else
1213                         {
1214                         al=SSL_AD_UNEXPECTED_MESSAGE;
1215                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1216                         goto f_err;
1217                         }
1218                 }
1219         /* not reached */
1220
1221 f_err:
1222         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1223 err:
1224         return(-1);
1225         }
1226
1227 int ssl3_do_change_cipher_spec(SSL *s)
1228         {
1229         int i;
1230         const char *sender;
1231         int slen;
1232
1233         if (s->state & SSL_ST_ACCEPT)
1234                 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1235         else
1236                 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1237
1238         if (s->s3->tmp.key_block == NULL)
1239                 {
1240                 s->session->cipher=s->s3->tmp.new_cipher;
1241                 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1242                 }
1243
1244         if (!s->method->ssl3_enc->change_cipher_state(s,i))
1245                 return(0);
1246
1247         /* we have to record the message digest at
1248          * this point so we can get it before we read
1249          * the finished message */
1250         if (s->state & SSL_ST_CONNECT)
1251                 {
1252                 sender=s->method->ssl3_enc->server_finished_label;
1253                 slen=s->method->ssl3_enc->server_finished_label_len;
1254                 }
1255         else
1256                 {
1257                 sender=s->method->ssl3_enc->client_finished_label;
1258                 slen=s->method->ssl3_enc->client_finished_label_len;
1259                 }
1260
1261         s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1262                 &(s->s3->finish_dgst1),
1263                 &(s->s3->finish_dgst2),
1264                 sender,slen,s->s3->tmp.peer_finish_md);
1265
1266         return(1);
1267         }
1268
1269 void ssl3_send_alert(SSL *s, int level, int desc)
1270         {
1271         /* Map tls/ssl alert value to correct one */
1272         desc=s->method->ssl3_enc->alert_value(desc);
1273         if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1274                 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1275         if (desc < 0) return;
1276         /* If a fatal one, remove from cache */
1277         if ((level == 2) && (s->session != NULL))
1278                 SSL_CTX_remove_session(s->ctx,s->session);
1279
1280         s->s3->alert_dispatch=1;
1281         s->s3->send_alert[0]=level;
1282         s->s3->send_alert[1]=desc;
1283         if (s->s3->wbuf.left == 0) /* data still being written out? */
1284                 s->method->ssl_dispatch_alert(s);
1285         /* else data is still being written out, we will get written
1286          * some time in the future */
1287         }
1288
1289 int ssl3_dispatch_alert(SSL *s)
1290         {
1291         int i,j;
1292         void (*cb)(const SSL *ssl,int type,int val)=NULL;
1293
1294         s->s3->alert_dispatch=0;
1295         i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1296         if (i <= 0)
1297                 {
1298                 s->s3->alert_dispatch=1;
1299                 }
1300         else
1301                 {
1302                 /* Alert sent to BIO.  If it is important, flush it now.
1303                  * If the message does not get sent due to non-blocking IO,
1304                  * we will not worry too much. */
1305                 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1306                         (void)BIO_flush(s->wbio);
1307
1308                 if (s->msg_callback)
1309                         s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1310
1311                 if (s->info_callback != NULL)
1312                         cb=s->info_callback;
1313                 else if (s->ctx->info_callback != NULL)
1314                         cb=s->ctx->info_callback;
1315
1316                 if (cb != NULL)
1317                         {
1318                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1319                         cb(s,SSL_CB_WRITE_ALERT,j);
1320                         }
1321                 }
1322         return(i);
1323         }