Fix for CVE-2014-0224
[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         /* For DTLS/UDP reads should not span multiple packets
145          * because the read operation returns the whole packet
146          * at once (as long as it fits into the buffer). */
147         if (SSL_version(s) == DTLS1_VERSION)
148                 {
149                 if ( s->s3->rbuf.left > 0 && n > s->s3->rbuf.left)
150                         n = s->s3->rbuf.left;
151                 }
152
153         /* if there is enough in the buffer from a previous read, take some */
154         if (s->s3->rbuf.left >= (int)n)
155                 {
156                 s->packet_length+=n;
157                 s->s3->rbuf.left-=n;
158                 s->s3->rbuf.offset+=n;
159                 return(n);
160                 }
161
162         /* else we need to read more data */
163         if (!s->read_ahead)
164                 max=n;
165
166         {
167                 /* avoid buffer overflow */
168                 int max_max = s->s3->rbuf.len - s->packet_length;
169                 if (max > max_max)
170                         max = max_max;
171         }
172         if (n > max) /* does not happen */
173                 {
174                 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
175                 return -1;
176                 }
177
178         off = s->packet_length;
179         newb = s->s3->rbuf.left;
180         /* Move any available bytes to front of buffer:
181          * 'off' bytes already pointed to by 'packet',
182          * 'newb' extra ones at the end */
183         if (s->packet != s->s3->rbuf.buf)
184                 {
185                 /*  off > 0 */
186                 memmove(s->s3->rbuf.buf, s->packet, off+newb);
187                 s->packet = s->s3->rbuf.buf;
188                 }
189
190         while (newb < n)
191                 {
192                 /* Now we have off+newb bytes at the front of s->s3->rbuf.buf and need
193                  * to read in more until we have off+n (up to off+max if possible) */
194
195                 clear_sys_error();
196                 if (s->rbio != NULL)
197                         {
198                         s->rwstate=SSL_READING;
199                         i=BIO_read(s->rbio,     &(s->s3->rbuf.buf[off+newb]), max-newb);
200                         }
201                 else
202                         {
203                         SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
204                         i = -1;
205                         }
206
207                 if (i <= 0)
208                         {
209                         s->s3->rbuf.left = newb;
210                         return(i);
211                         }
212                 newb+=i;
213                 /* reads should *never* span multiple packets for DTLS because
214                  * the underlying transport protocol is message oriented as opposed
215                  * to byte oriented as in the TLS case. */
216                 if (SSL_version(s) == DTLS1_VERSION)
217                         {
218                         if (n > newb)
219                                 n = newb; /* makes the while condition false */
220                         }
221                 }
222
223         /* done reading, now the book-keeping */
224         s->s3->rbuf.offset = off + n;
225         s->s3->rbuf.left = newb - n;
226         s->packet_length += n;
227         s->rwstate=SSL_NOTHING;
228         return(n);
229         }
230
231 /* Call this to get a new input record.
232  * It will return <= 0 if more data is needed, normally due to an error
233  * or non-blocking IO.
234  * When it finishes, one packet has been decoded and can be found in
235  * ssl->s3->rrec.type    - is the type of record
236  * ssl->s3->rrec.data,   - data
237  * ssl->s3->rrec.length, - number of bytes
238  */
239 /* used only by ssl3_read_bytes */
240 static int ssl3_get_record(SSL *s)
241         {
242         int ssl_major,ssl_minor,al;
243         int enc_err,n,i,ret= -1;
244         SSL3_RECORD *rr;
245         SSL_SESSION *sess;
246         unsigned char *p;
247         unsigned char md[EVP_MAX_MD_SIZE];
248         short version;
249         unsigned mac_size, orig_len;
250         size_t extra;
251
252         rr= &(s->s3->rrec);
253         sess=s->session;
254
255         if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
256                 extra=SSL3_RT_MAX_EXTRA;
257         else
258                 extra=0;
259         if (extra != s->s3->rbuf.len - SSL3_RT_MAX_PACKET_SIZE)
260                 {
261                 /* actually likely an application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER
262                  * set after ssl3_setup_buffers() was done */
263                 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
264                 return -1;
265                 }
266
267 again:
268         /* check if we have the header */
269         if (    (s->rstate != SSL_ST_READ_BODY) ||
270                 (s->packet_length < SSL3_RT_HEADER_LENGTH)) 
271                 {
272                 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
273                 if (n <= 0) return(n); /* error or non-blocking */
274                 s->rstate=SSL_ST_READ_BODY;
275
276                 p=s->packet;
277
278                 /* Pull apart the header into the SSL3_RECORD */
279                 rr->type= *(p++);
280                 ssl_major= *(p++);
281                 ssl_minor= *(p++);
282                 version=(ssl_major<<8)|ssl_minor;
283                 n2s(p,rr->length);
284
285                 /* Lets check version */
286                 if (!s->first_packet)
287                         {
288                         if (version != s->version)
289                                 {
290                                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
291                                 if ((s->version & 0xFF00) == (version & 0xFF00))
292                                         /* Send back error using their minor version number :-) */
293                                         s->version = (unsigned short)version;
294                                 al=SSL_AD_PROTOCOL_VERSION;
295                                 goto f_err;
296                                 }
297                         }
298
299                 if ((version>>8) != SSL3_VERSION_MAJOR)
300                         {
301                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
302                         goto err;
303                         }
304
305                 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
306                         {
307                         al=SSL_AD_RECORD_OVERFLOW;
308                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
309                         goto f_err;
310                         }
311
312                 /* now s->rstate == SSL_ST_READ_BODY */
313                 }
314
315         /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
316
317         if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
318                 {
319                 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
320                 i=rr->length;
321                 n=ssl3_read_n(s,i,i,1);
322                 if (n <= 0) return(n); /* error or non-blocking io */
323                 /* now n == rr->length,
324                  * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
325                 }
326
327         s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
328
329         /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
330          * and we have that many bytes in s->packet
331          */
332         rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
333
334         /* ok, we can now read from 's->packet' data into 'rr'
335          * rr->input points at rr->length bytes, which
336          * need to be copied into rr->data by either
337          * the decryption or by the decompression
338          * When the data is 'copied' into the rr->data buffer,
339          * rr->input will be pointed at the new buffer */ 
340
341         /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
342          * rr->length bytes of encrypted compressed stuff. */
343
344         /* check is not needed I believe */
345         if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
346                 {
347                 al=SSL_AD_RECORD_OVERFLOW;
348                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
349                 goto f_err;
350                 }
351
352         /* decrypt in place in 'rr->input' */
353         rr->data=rr->input;
354
355         enc_err = s->method->ssl3_enc->enc(s,0);
356         /* enc_err is:
357          *    0: (in non-constant time) if the record is publically invalid.
358          *    1: if the padding is valid
359          *    -1: if the padding is invalid */
360         if (enc_err == 0)
361                 {
362                 al=SSL_AD_DECRYPTION_FAILED;
363                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
364                 goto f_err;
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                 {
378                 /* s->read_hash != NULL => mac_size != -1 */
379                 unsigned char *mac = NULL;
380                 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
381                 mac_size=EVP_MD_size(s->read_hash);
382                 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
383
384                 /* kludge: *_cbc_remove_padding passes padding length in rr->type */
385                 orig_len = rr->length+((unsigned int)rr->type>>8);
386
387                 /* orig_len is the length of the record before any padding was
388                  * removed. This is public information, as is the MAC in use,
389                  * therefore we can safely process the record in a different
390                  * amount of time if it's too short to possibly contain a MAC.
391                  */
392                 if (orig_len < mac_size ||
393                     /* CBC records must have a padding length byte too. */
394                     (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
395                      orig_len < mac_size+1))
396                         {
397                         al=SSL_AD_DECODE_ERROR;
398                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
399                         goto f_err;
400                         }
401
402                 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE)
403                         {
404                         /* We update the length so that the TLS header bytes
405                          * can be constructed correctly but we need to extract
406                          * the MAC in constant time from within the record,
407                          * without leaking the contents of the padding bytes.
408                          * */
409                         mac = mac_tmp;
410                         ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
411                         rr->length -= mac_size;
412                         }
413                 else
414                         {
415                         /* In this case there's no padding, so |orig_len|
416                          * equals |rec->length| and we checked that there's
417                          * enough bytes for |mac_size| above. */
418                         rr->length -= mac_size;
419                         mac = &rr->data[rr->length];
420                         }
421
422                 i=s->method->ssl3_enc->mac(s,md,0 /* not send */);
423                 if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
424                         enc_err = -1;
425                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
426                         enc_err = -1;
427                 }
428
429         if (enc_err < 0)
430                 {
431                 /* A separate 'decryption_failed' alert was introduced with TLS 1.0,
432                  * SSL 3.0 only has 'bad_record_mac'.  But unless a decryption
433                  * failure is directly visible from the ciphertext anyway,
434                  * we should not reveal which kind of error occured -- this
435                  * might become visible to an attacker (e.g. via a logfile) */
436                 al=SSL_AD_BAD_RECORD_MAC;
437                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
438                 goto f_err;
439                 }
440
441         /* r->length is now just compressed */
442         if (s->expand != NULL)
443                 {
444                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
445                         {
446                         al=SSL_AD_RECORD_OVERFLOW;
447                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
448                         goto f_err;
449                         }
450                 if (!ssl3_do_uncompress(s))
451                         {
452                         al=SSL_AD_DECOMPRESSION_FAILURE;
453                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
454                         goto f_err;
455                         }
456                 }
457
458         if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
459                 {
460                 al=SSL_AD_RECORD_OVERFLOW;
461                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
462                 goto f_err;
463                 }
464
465         rr->off=0;
466         /* So at this point the following is true
467          * ssl->s3->rrec.type   is the type of record
468          * ssl->s3->rrec.length == number of bytes in record
469          * ssl->s3->rrec.off    == offset to first valid byte
470          * ssl->s3->rrec.data   == where to take bytes from, increment
471          *                         after use :-).
472          */
473
474         /* we have pulled in a full packet so zero things */
475         s->packet_length=0;
476
477         /* just read a 0 length packet */
478         if (rr->length == 0) goto again;
479
480         return(1);
481
482 f_err:
483         ssl3_send_alert(s,SSL3_AL_FATAL,al);
484 err:
485         return(ret);
486         }
487
488 int ssl3_do_uncompress(SSL *ssl)
489         {
490 #ifndef OPENSSL_NO_COMP
491         int i;
492         SSL3_RECORD *rr;
493
494         rr= &(ssl->s3->rrec);
495         i=COMP_expand_block(ssl->expand,rr->comp,
496                 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
497         if (i < 0)
498                 return(0);
499         else
500                 rr->length=i;
501         rr->data=rr->comp;
502 #endif
503         return(1);
504         }
505
506 int ssl3_do_compress(SSL *ssl)
507         {
508 #ifndef OPENSSL_NO_COMP
509         int i;
510         SSL3_RECORD *wr;
511
512         wr= &(ssl->s3->wrec);
513         i=COMP_compress_block(ssl->compress,wr->data,
514                 SSL3_RT_MAX_COMPRESSED_LENGTH,
515                 wr->input,(int)wr->length);
516         if (i < 0)
517                 return(0);
518         else
519                 wr->length=i;
520
521         wr->input=wr->data;
522 #endif
523         return(1);
524         }
525
526 /* Call this to write data in records of type 'type'
527  * It will return <= 0 if not all data has been sent or non-blocking IO.
528  */
529 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
530         {
531         const unsigned char *buf=buf_;
532         unsigned int n,nw;
533         int i,tot;
534
535         s->rwstate=SSL_NOTHING;
536         OPENSSL_assert(s->s3->wnum < INT_MAX);
537         tot=s->s3->wnum;
538         s->s3->wnum=0;
539
540         if (SSL_in_init(s) && !s->in_handshake)
541                 {
542                 i=s->handshake_func(s);
543                 if (i < 0) return(i);
544                 if (i == 0)
545                         {
546                         SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
547                         return -1;
548                         }
549                 }
550
551         /* ensure that if we end up with a smaller value of data to write 
552          * out than the the original len from a write which didn't complete 
553          * for non-blocking I/O and also somehow ended up avoiding 
554          * the check for this in ssl3_write_pending/SSL_R_BAD_WRITE_RETRY as
555          * it must never be possible to end up with (len-tot) as a large
556          * number that will then promptly send beyond the end of the users
557          * buffer ... so we trap and report the error in a way the user
558          * will notice
559          */
560         if (len < tot)
561                 {
562                 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_BAD_LENGTH);
563                 return(-1);
564                 }
565
566
567         n=(len-tot);
568         for (;;)
569                 {
570                 if (n > SSL3_RT_MAX_PLAIN_LENGTH)
571                         nw=SSL3_RT_MAX_PLAIN_LENGTH;
572                 else
573                         nw=n;
574
575                 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
576                 if (i <= 0)
577                         {
578                         s->s3->wnum=tot;
579                         return i;
580                         }
581
582                 if ((i == (int)n) ||
583                         (type == SSL3_RT_APPLICATION_DATA &&
584                          (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
585                         {
586                         /* next chunk of data should get another prepended empty fragment
587                          * in ciphersuites with known-IV weakness: */
588                         s->s3->empty_fragment_done = 0;
589                         
590                         return tot+i;
591                         }
592
593                 n-=i;
594                 tot+=i;
595                 }
596         }
597
598 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
599                          unsigned int len, int create_empty_fragment)
600         {
601         unsigned char *p,*plen;
602         int i,mac_size,clear=0;
603         int prefix_len = 0;
604         SSL3_RECORD *wr;
605         SSL3_BUFFER *wb;
606         SSL_SESSION *sess;
607
608         /* first check if there is a SSL3_BUFFER still being written
609          * out.  This will happen with non blocking IO */
610         if (s->s3->wbuf.left != 0)
611                 return(ssl3_write_pending(s,type,buf,len));
612
613         /* If we have an alert to send, lets send it */
614         if (s->s3->alert_dispatch)
615                 {
616                 i=s->method->ssl_dispatch_alert(s);
617                 if (i <= 0)
618                         return(i);
619                 /* if it went, fall through and send more stuff */
620                 }
621
622         if (len == 0 && !create_empty_fragment)
623                 return 0;
624
625         wr= &(s->s3->wrec);
626         wb= &(s->s3->wbuf);
627         sess=s->session;
628
629         if (    (sess == NULL) ||
630                 (s->enc_write_ctx == NULL) ||
631                 (s->write_hash == NULL))
632                 clear=1;
633
634         if (clear)
635                 mac_size=0;
636         else
637                 mac_size=EVP_MD_size(s->write_hash);
638
639         /* 'create_empty_fragment' is true only when this function calls itself */
640         if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
641                 {
642                 /* countermeasure against known-IV weakness in CBC ciphersuites
643                  * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
644
645                 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
646                         {
647                         /* recursive function call with 'create_empty_fragment' set;
648                          * this prepares and buffers the data for an empty fragment
649                          * (these 'prefix_len' bytes are sent out later
650                          * together with the actual payload) */
651                         prefix_len = do_ssl3_write(s, type, buf, 0, 1);
652                         if (prefix_len <= 0)
653                                 goto err;
654
655                         if (s->s3->wbuf.len < (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE)
656                                 {
657                                 /* insufficient space */
658                                 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
659                                 goto err;
660                                 }
661                         }
662                 
663                 s->s3->empty_fragment_done = 1;
664                 }
665
666         p = wb->buf + prefix_len;
667
668         /* write the header */
669
670         *(p++)=type&0xff;
671         wr->type=type;
672
673         *(p++)=(s->version>>8);
674         *(p++)=s->version&0xff;
675
676         /* field where we are to write out packet length */
677         plen=p; 
678         p+=2;
679
680         /* lets setup the record stuff. */
681         wr->data=p;
682         wr->length=(int)len;
683         wr->input=(unsigned char *)buf;
684
685         /* we now 'read' from wr->input, wr->length bytes into
686          * wr->data */
687
688         /* first we compress */
689         if (s->compress != NULL)
690                 {
691                 if (!ssl3_do_compress(s))
692                         {
693                         SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
694                         goto err;
695                         }
696                 }
697         else
698                 {
699                 memcpy(wr->data,wr->input,wr->length);
700                 wr->input=wr->data;
701                 }
702
703         /* we should still have the output to wr->data and the input
704          * from wr->input.  Length should be wr->length.
705          * wr->data still points in the wb->buf */
706
707         if (mac_size != 0)
708                 {
709                 s->method->ssl3_enc->mac(s,&(p[wr->length]),1);
710                 wr->length+=mac_size;
711                 wr->input=p;
712                 wr->data=p;
713                 }
714
715         /* ssl3_enc can only have an error on read */
716         s->method->ssl3_enc->enc(s,1);
717
718         /* record length after mac and block padding */
719         s2n(wr->length,plen);
720
721         /* we should now have
722          * wr->data pointing to the encrypted data, which is
723          * wr->length long */
724         wr->type=type; /* not needed but helps for debugging */
725         wr->length+=SSL3_RT_HEADER_LENGTH;
726
727         if (create_empty_fragment)
728                 {
729                 /* we are in a recursive call;
730                  * just return the length, don't write out anything here
731                  */
732                 return wr->length;
733                 }
734
735         /* now let's set up wb */
736         wb->left = prefix_len + wr->length;
737         wb->offset = 0;
738
739         /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
740         s->s3->wpend_tot=len;
741         s->s3->wpend_buf=buf;
742         s->s3->wpend_type=type;
743         s->s3->wpend_ret=len;
744
745         /* we now just need to write the buffer */
746         return ssl3_write_pending(s,type,buf,len);
747 err:
748         return -1;
749         }
750
751 /* if s->s3->wbuf.left != 0, we need to call this */
752 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
753         unsigned int len)
754         {
755         int i;
756
757 /* XXXX */
758         if ((s->s3->wpend_tot > (int)len)
759                 || ((s->s3->wpend_buf != buf) &&
760                         !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
761                 || (s->s3->wpend_type != type))
762                 {
763                 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
764                 return(-1);
765                 }
766
767         for (;;)
768                 {
769                 clear_sys_error();
770                 if (s->wbio != NULL)
771                         {
772                         s->rwstate=SSL_WRITING;
773                         i=BIO_write(s->wbio,
774                                 (char *)&(s->s3->wbuf.buf[s->s3->wbuf.offset]),
775                                 (unsigned int)s->s3->wbuf.left);
776                         }
777                 else
778                         {
779                         SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
780                         i= -1;
781                         }
782                 if (i == s->s3->wbuf.left)
783                         {
784                         s->s3->wbuf.left=0;
785                         s->rwstate=SSL_NOTHING;
786                         return(s->s3->wpend_ret);
787                         }
788                 else if (i <= 0) {
789                         if (s->version == DTLS1_VERSION ||
790                             s->version == DTLS1_BAD_VER) {
791                                 /* For DTLS, just drop it. That's kind of the whole
792                                    point in using a datagram service */
793                                 s->s3->wbuf.left = 0;
794                         }
795                         return(i);
796                 }
797                 s->s3->wbuf.offset+=i;
798                 s->s3->wbuf.left-=i;
799                 }
800         }
801
802 /* Return up to 'len' payload bytes received in 'type' records.
803  * 'type' is one of the following:
804  *
805  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
806  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
807  *   -  0 (during a shutdown, no data has to be returned)
808  *
809  * If we don't have stored data to work from, read a SSL/TLS record first
810  * (possibly multiple records if we still don't have anything to return).
811  *
812  * This function must handle any surprises the peer may have for us, such as
813  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
814  * a surprise, but handled as if it were), or renegotiation requests.
815  * Also if record payloads contain fragments too small to process, we store
816  * them until there is enough for the respective protocol (the record protocol
817  * may use arbitrary fragmentation and even interleaving):
818  *     Change cipher spec protocol
819  *             just 1 byte needed, no need for keeping anything stored
820  *     Alert protocol
821  *             2 bytes needed (AlertLevel, AlertDescription)
822  *     Handshake protocol
823  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
824  *             to detect unexpected Client Hello and Hello Request messages
825  *             here, anything else is handled by higher layers
826  *     Application data protocol
827  *             none of our business
828  */
829 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
830         {
831         int al,i,j,ret;
832         unsigned int n;
833         SSL3_RECORD *rr;
834         void (*cb)(const SSL *ssl,int type2,int val)=NULL;
835
836         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
837                 if (!ssl3_setup_buffers(s))
838                         return(-1);
839
840         if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) ||
841             (peek && (type != SSL3_RT_APPLICATION_DATA)))
842                 {
843                 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
844                 return -1;
845                 }
846
847         if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
848                 /* (partially) satisfy request from storage */
849                 {
850                 unsigned char *src = s->s3->handshake_fragment;
851                 unsigned char *dst = buf;
852                 unsigned int k;
853
854                 /* peek == 0 */
855                 n = 0;
856                 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
857                         {
858                         *dst++ = *src++;
859                         len--; s->s3->handshake_fragment_len--;
860                         n++;
861                         }
862                 /* move any remaining fragment bytes: */
863                 for (k = 0; k < s->s3->handshake_fragment_len; k++)
864                         s->s3->handshake_fragment[k] = *src++;
865                 return n;
866         }
867
868         /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
869
870         if (!s->in_handshake && SSL_in_init(s))
871                 {
872                 /* type == SSL3_RT_APPLICATION_DATA */
873                 i=s->handshake_func(s);
874                 if (i < 0) return(i);
875                 if (i == 0)
876                         {
877                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
878                         return(-1);
879                         }
880                 }
881 start:
882         s->rwstate=SSL_NOTHING;
883
884         /* s->s3->rrec.type         - is the type of record
885          * s->s3->rrec.data,    - data
886          * s->s3->rrec.off,     - offset into 'data' for next read
887          * s->s3->rrec.length,  - number of bytes. */
888         rr = &(s->s3->rrec);
889
890         /* get new packet if necessary */
891         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
892                 {
893                 ret=ssl3_get_record(s);
894                 if (ret <= 0) return(ret);
895                 }
896
897         /* we now have a packet which can be read and processed */
898
899         if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
900                                        * reset by ssl3_get_finished */
901                 && (rr->type != SSL3_RT_HANDSHAKE))
902                 {
903                 al=SSL_AD_UNEXPECTED_MESSAGE;
904                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
905                 goto f_err;
906                 }
907
908         /* If the other end has shut down, throw anything we read away
909          * (even in 'peek' mode) */
910         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
911                 {
912                 rr->length=0;
913                 s->rwstate=SSL_NOTHING;
914                 return(0);
915                 }
916
917
918         if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
919                 {
920                 /* make sure that we are not getting application data when we
921                  * are doing a handshake for the first time */
922                 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
923                         (s->enc_read_ctx == NULL))
924                         {
925                         al=SSL_AD_UNEXPECTED_MESSAGE;
926                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
927                         goto f_err;
928                         }
929
930                 if (len <= 0) return(len);
931
932                 if ((unsigned int)len > rr->length)
933                         n = rr->length;
934                 else
935                         n = (unsigned int)len;
936
937                 memcpy(buf,&(rr->data[rr->off]),n);
938                 if (!peek)
939                         {
940                         rr->length-=n;
941                         rr->off+=n;
942                         if (rr->length == 0)
943                                 {
944                                 s->rstate=SSL_ST_READ_HEADER;
945                                 rr->off=0;
946                                 }
947                         }
948                 return(n);
949                 }
950
951
952         /* If we get here, then type != rr->type; if we have a handshake
953          * message, then it was unexpected (Hello Request or Client Hello). */
954
955         /* In case of record types for which we have 'fragment' storage,
956          * fill that so that we can process the data at a fixed place.
957          */
958                 {
959                 unsigned int dest_maxlen = 0;
960                 unsigned char *dest = NULL;
961                 unsigned int *dest_len = NULL;
962
963                 if (rr->type == SSL3_RT_HANDSHAKE)
964                         {
965                         dest_maxlen = sizeof s->s3->handshake_fragment;
966                         dest = s->s3->handshake_fragment;
967                         dest_len = &s->s3->handshake_fragment_len;
968                         }
969                 else if (rr->type == SSL3_RT_ALERT)
970                         {
971                         dest_maxlen = sizeof s->s3->alert_fragment;
972                         dest = s->s3->alert_fragment;
973                         dest_len = &s->s3->alert_fragment_len;
974                         }
975
976                 if (dest_maxlen > 0)
977                         {
978                         n = dest_maxlen - *dest_len; /* available space in 'dest' */
979                         if (rr->length < n)
980                                 n = rr->length; /* available bytes */
981
982                         /* now move 'n' bytes: */
983                         while (n-- > 0)
984                                 {
985                                 dest[(*dest_len)++] = rr->data[rr->off++];
986                                 rr->length--;
987                                 }
988
989                         if (*dest_len < dest_maxlen)
990                                 goto start; /* fragment was too small */
991                         }
992                 }
993
994         /* s->s3->handshake_fragment_len == 4  iff  rr->type == SSL3_RT_HANDSHAKE;
995          * s->s3->alert_fragment_len == 2      iff  rr->type == SSL3_RT_ALERT.
996          * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
997
998         /* If we are a client, check for an incoming 'Hello Request': */
999         if ((!s->server) &&
1000                 (s->s3->handshake_fragment_len >= 4) &&
1001                 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1002                 (s->session != NULL) && (s->session->cipher != NULL))
1003                 {
1004                 s->s3->handshake_fragment_len = 0;
1005
1006                 if ((s->s3->handshake_fragment[1] != 0) ||
1007                         (s->s3->handshake_fragment[2] != 0) ||
1008                         (s->s3->handshake_fragment[3] != 0))
1009                         {
1010                         al=SSL_AD_DECODE_ERROR;
1011                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1012                         goto f_err;
1013                         }
1014
1015                 if (s->msg_callback)
1016                         s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
1017
1018                 if (SSL_is_init_finished(s) &&
1019                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1020                         !s->s3->renegotiate)
1021                         {
1022                         ssl3_renegotiate(s);
1023                         if (ssl3_renegotiate_check(s))
1024                                 {
1025                                 i=s->handshake_func(s);
1026                                 if (i < 0) return(i);
1027                                 if (i == 0)
1028                                         {
1029                                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1030                                         return(-1);
1031                                         }
1032
1033                                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1034                                         {
1035                                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1036                                                 {
1037                                                 BIO *bio;
1038                                                 /* In the case where we try to read application data,
1039                                                  * but we trigger an SSL handshake, we return -1 with
1040                                                  * the retry option set.  Otherwise renegotiation may
1041                                                  * cause nasty problems in the blocking world */
1042                                                 s->rwstate=SSL_READING;
1043                                                 bio=SSL_get_rbio(s);
1044                                                 BIO_clear_retry_flags(bio);
1045                                                 BIO_set_retry_read(bio);
1046                                                 return(-1);
1047                                                 }
1048                                         }
1049                                 }
1050                         }
1051                 /* we either finished a handshake or ignored the request,
1052                  * now try again to obtain the (application) data we were asked for */
1053                 goto start;
1054                 }
1055         /* If we are a server and get a client hello when renegotiation isn't
1056          * allowed send back a no renegotiation alert and carry on.
1057          * WARNING: experimental code, needs reviewing (steve)
1058          */
1059         if (s->server &&
1060                 SSL_is_init_finished(s) &&
1061                 !s->s3->send_connection_binding &&
1062                 (s->version > SSL3_VERSION) &&
1063                 (s->s3->handshake_fragment_len >= 4) &&
1064                 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1065                 (s->session != NULL) && (s->session->cipher != NULL) &&
1066                 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1067                 
1068                 {
1069                 /*s->s3->handshake_fragment_len = 0;*/
1070                 rr->length = 0;
1071                 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1072                 goto start;
1073                 }
1074         if (s->s3->alert_fragment_len >= 2)
1075                 {
1076                 int alert_level = s->s3->alert_fragment[0];
1077                 int alert_descr = s->s3->alert_fragment[1];
1078
1079                 s->s3->alert_fragment_len = 0;
1080
1081                 if (s->msg_callback)
1082                         s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1083
1084                 if (s->info_callback != NULL)
1085                         cb=s->info_callback;
1086                 else if (s->ctx->info_callback != NULL)
1087                         cb=s->ctx->info_callback;
1088
1089                 if (cb != NULL)
1090                         {
1091                         j = (alert_level << 8) | alert_descr;
1092                         cb(s, SSL_CB_READ_ALERT, j);
1093                         }
1094
1095                 if (alert_level == 1) /* warning */
1096                         {
1097                         s->s3->warn_alert = alert_descr;
1098                         if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1099                                 {
1100                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1101                                 return(0);
1102                                 }
1103                         /* This is a warning but we receive it if we requested
1104                          * renegotiation and the peer denied it. Terminate with
1105                          * a fatal alert because if application tried to
1106                          * renegotiatie it presumably had a good reason and
1107                          * expects it to succeed.
1108                          *
1109                          * In future we might have a renegotiation where we
1110                          * don't care if the peer refused it where we carry on.
1111                          */
1112                         else if (alert_descr == SSL_AD_NO_RENEGOTIATION)
1113                                 {
1114                                 al = SSL_AD_HANDSHAKE_FAILURE;
1115                                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION);
1116                                 goto f_err;
1117                                 }
1118                         }
1119                 else if (alert_level == 2) /* fatal */
1120                         {
1121                         char tmp[16];
1122
1123                         s->rwstate=SSL_NOTHING;
1124                         s->s3->fatal_alert = alert_descr;
1125                         SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1126                         BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1127                         ERR_add_error_data(2,"SSL alert number ",tmp);
1128                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1129                         SSL_CTX_remove_session(s->ctx,s->session);
1130                         return(0);
1131                         }
1132                 else
1133                         {
1134                         al=SSL_AD_ILLEGAL_PARAMETER;
1135                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1136                         goto f_err;
1137                         }
1138
1139                 goto start;
1140                 }
1141
1142         if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1143                 {
1144                 s->rwstate=SSL_NOTHING;
1145                 rr->length=0;
1146                 return(0);
1147                 }
1148
1149         if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1150                 {
1151                 /* 'Change Cipher Spec' is just a single byte, so we know
1152                  * exactly what the record payload has to look like */
1153                 if (    (rr->length != 1) || (rr->off != 0) ||
1154                         (rr->data[0] != SSL3_MT_CCS))
1155                         {
1156                         al=SSL_AD_ILLEGAL_PARAMETER;
1157                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1158                         goto f_err;
1159                         }
1160
1161                 /* Check we have a cipher to change to */
1162                 if (s->s3->tmp.new_cipher == NULL)
1163                         {
1164                         al=SSL_AD_UNEXPECTED_MESSAGE;
1165                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1166                         goto f_err;
1167                         }
1168
1169                 if (!(s->s3->flags & SSL3_FLAGS_CCS_OK))
1170                         {
1171                         al=SSL_AD_UNEXPECTED_MESSAGE;
1172                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1173                         goto f_err;
1174                         }
1175
1176                 s->s3->flags &= ~SSL3_FLAGS_CCS_OK;
1177
1178                 rr->length=0;
1179
1180                 if (s->msg_callback)
1181                         s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1182
1183                 s->s3->change_cipher_spec=1;
1184                 if (!ssl3_do_change_cipher_spec(s))
1185                         goto err;
1186                 else
1187                         goto start;
1188                 }
1189
1190         /* Unexpected handshake message (Client Hello, or protocol violation) */
1191         if ((s->s3->handshake_fragment_len >= 4) &&     !s->in_handshake)
1192                 {
1193                 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1194                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1195                         {
1196 #if 0 /* worked only because C operator preferences are not as expected (and
1197        * because this is not really needed for clients except for detecting
1198        * protocol violations): */
1199                         s->state=SSL_ST_BEFORE|(s->server)
1200                                 ?SSL_ST_ACCEPT
1201                                 :SSL_ST_CONNECT;
1202 #else
1203                         s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1204 #endif
1205                         s->new_session=1;
1206                         }
1207                 i=s->handshake_func(s);
1208                 if (i < 0) return(i);
1209                 if (i == 0)
1210                         {
1211                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1212                         return(-1);
1213                         }
1214
1215                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1216                         {
1217                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1218                                 {
1219                                 BIO *bio;
1220                                 /* In the case where we try to read application data,
1221                                  * but we trigger an SSL handshake, we return -1 with
1222                                  * the retry option set.  Otherwise renegotiation may
1223                                  * cause nasty problems in the blocking world */
1224                                 s->rwstate=SSL_READING;
1225                                 bio=SSL_get_rbio(s);
1226                                 BIO_clear_retry_flags(bio);
1227                                 BIO_set_retry_read(bio);
1228                                 return(-1);
1229                                 }
1230                         }
1231                 goto start;
1232                 }
1233
1234         switch (rr->type)
1235                 {
1236         default:
1237 #ifndef OPENSSL_NO_TLS
1238                 /* TLS just ignores unknown message types */
1239                 if (s->version == TLS1_VERSION)
1240                         {
1241                         rr->length = 0;
1242                         goto start;
1243                         }
1244 #endif
1245                 al=SSL_AD_UNEXPECTED_MESSAGE;
1246                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1247                 goto f_err;
1248         case SSL3_RT_CHANGE_CIPHER_SPEC:
1249         case SSL3_RT_ALERT:
1250         case SSL3_RT_HANDSHAKE:
1251                 /* we already handled all of these, with the possible exception
1252                  * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1253                  * should not happen when type != rr->type */
1254                 al=SSL_AD_UNEXPECTED_MESSAGE;
1255                 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1256                 goto f_err;
1257         case SSL3_RT_APPLICATION_DATA:
1258                 /* At this point, we were expecting handshake data,
1259                  * but have application data.  If the library was
1260                  * running inside ssl3_read() (i.e. in_read_app_data
1261                  * is set) and it makes sense to read application data
1262                  * at this point (session renegotiation not yet started),
1263                  * we will indulge it.
1264                  */
1265                 if (s->s3->in_read_app_data &&
1266                         (s->s3->total_renegotiations != 0) &&
1267                         ((
1268                                 (s->state & SSL_ST_CONNECT) &&
1269                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1270                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1271                                 ) || (
1272                                         (s->state & SSL_ST_ACCEPT) &&
1273                                         (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1274                                         (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1275                                         )
1276                                 ))
1277                         {
1278                         s->s3->in_read_app_data=2;
1279                         return(-1);
1280                         }
1281                 else
1282                         {
1283                         al=SSL_AD_UNEXPECTED_MESSAGE;
1284                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1285                         goto f_err;
1286                         }
1287                 }
1288         /* not reached */
1289
1290 f_err:
1291         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1292 err:
1293         return(-1);
1294         }
1295
1296 int ssl3_do_change_cipher_spec(SSL *s)
1297         {
1298         int i;
1299         const char *sender;
1300         int slen;
1301
1302         if (s->state & SSL_ST_ACCEPT)
1303                 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1304         else
1305                 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1306
1307         if (s->s3->tmp.key_block == NULL)
1308                 {
1309                 if (s->session == NULL) 
1310                         {
1311                         /* might happen if dtls1_read_bytes() calls this */
1312                         SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY);
1313                         return (0);
1314                         }
1315
1316                 s->session->cipher=s->s3->tmp.new_cipher;
1317                 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1318                 }
1319
1320         if (!s->method->ssl3_enc->change_cipher_state(s,i))
1321                 return(0);
1322
1323         /* we have to record the message digest at
1324          * this point so we can get it before we read
1325          * the finished message */
1326         if (s->state & SSL_ST_CONNECT)
1327                 {
1328                 sender=s->method->ssl3_enc->server_finished_label;
1329                 slen=s->method->ssl3_enc->server_finished_label_len;
1330                 }
1331         else
1332                 {
1333                 sender=s->method->ssl3_enc->client_finished_label;
1334                 slen=s->method->ssl3_enc->client_finished_label_len;
1335                 }
1336
1337         s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1338                 &(s->s3->finish_dgst1),
1339                 &(s->s3->finish_dgst2),
1340                 sender,slen,s->s3->tmp.peer_finish_md);
1341
1342         return(1);
1343         }
1344
1345 int ssl3_send_alert(SSL *s, int level, int desc)
1346         {
1347         /* Map tls/ssl alert value to correct one */
1348         desc=s->method->ssl3_enc->alert_value(desc);
1349         if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1350                 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1351         if (desc < 0) return -1;
1352         /* If a fatal one, remove from cache */
1353         if ((level == 2) && (s->session != NULL))
1354                 SSL_CTX_remove_session(s->ctx,s->session);
1355
1356         s->s3->alert_dispatch=1;
1357         s->s3->send_alert[0]=level;
1358         s->s3->send_alert[1]=desc;
1359         if (s->s3->wbuf.left == 0) /* data still being written out? */
1360                 return s->method->ssl_dispatch_alert(s);
1361         /* else data is still being written out, we will get written
1362          * some time in the future */
1363         return -1;
1364         }
1365
1366 int ssl3_dispatch_alert(SSL *s)
1367         {
1368         int i,j;
1369         void (*cb)(const SSL *ssl,int type,int val)=NULL;
1370
1371         s->s3->alert_dispatch=0;
1372         i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1373         if (i <= 0)
1374                 {
1375                 s->s3->alert_dispatch=1;
1376                 }
1377         else
1378                 {
1379                 /* Alert sent to BIO.  If it is important, flush it now.
1380                  * If the message does not get sent due to non-blocking IO,
1381                  * we will not worry too much. */
1382                 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1383                         (void)BIO_flush(s->wbio);
1384
1385                 if (s->msg_callback)
1386                         s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1387
1388                 if (s->info_callback != NULL)
1389                         cb=s->info_callback;
1390                 else if (s->ctx->info_callback != NULL)
1391                         cb=s->ctx->info_callback;
1392
1393                 if (cb != NULL)
1394                         {
1395                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1396                         cb(s,SSL_CB_WRITE_ALERT,j);
1397                         }
1398                 }
1399         return(i);
1400         }