Add support for canonical generation of DSA parameter g.
[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 #include <openssl/rand.h>
119
120 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
121                          unsigned int len, int create_empty_fragment);
122 static int ssl3_get_record(SSL *s);
123
124 int ssl3_read_n(SSL *s, int n, int max, int extend)
125         {
126         /* If extend == 0, obtain new n-byte packet; if extend == 1, increase
127          * packet by another n bytes.
128          * The packet will be in the sub-array of s->s3->rbuf.buf specified
129          * by s->packet and s->packet_length.
130          * (If s->read_ahead is set, 'max' bytes may be stored in rbuf
131          * [plus s->packet_length bytes if extend == 1].)
132          */
133         int i,len,left;
134         long align=0;
135         unsigned char *pkt;
136         SSL3_BUFFER *rb;
137
138         if (n <= 0) return n;
139
140         rb    = &(s->s3->rbuf);
141         if (rb->buf == NULL)
142                 if (!ssl3_setup_read_buffer(s))
143                         return -1;
144
145         left  = rb->left;
146 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
147         align = (long)rb->buf + SSL3_RT_HEADER_LENGTH;
148         align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
149 #endif
150
151         if (!extend)
152                 {
153                 /* start with empty packet ... */
154                 if (left == 0)
155                         rb->offset = align;
156                 else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH)
157                         {
158                         /* check if next packet length is large
159                          * enough to justify payload alignment... */
160                         pkt = rb->buf + rb->offset;
161                         if (pkt[0] == SSL3_RT_APPLICATION_DATA
162                             && (pkt[3]<<8|pkt[4]) >= 128)
163                                 {
164                                 /* Note that even if packet is corrupted
165                                  * and its length field is insane, we can
166                                  * only be led to wrong decision about
167                                  * whether memmove will occur or not.
168                                  * Header values has no effect on memmove
169                                  * arguments and therefore no buffer
170                                  * overrun can be triggered. */
171                                 memmove (rb->buf+align,pkt,left);
172                                 rb->offset = align;
173                                 }
174                         }
175                 s->packet = rb->buf + rb->offset;
176                 s->packet_length = 0;
177                 /* ... now we can act as if 'extend' was set */
178                 }
179
180         /* For DTLS/UDP reads should not span multiple packets
181          * because the read operation returns the whole packet
182          * at once (as long as it fits into the buffer). */
183         if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER)
184                 {
185                 if (left > 0 && n > left)
186                         n = left;
187                 }
188
189         /* if there is enough in the buffer from a previous read, take some */
190         if (left >= n)
191                 {
192                 s->packet_length+=n;
193                 rb->left=left-n;
194                 rb->offset+=n;
195                 return(n);
196                 }
197
198         /* else we need to read more data */
199
200         len = s->packet_length;
201         pkt = rb->buf+align;
202         /* Move any available bytes to front of buffer:
203          * 'len' bytes already pointed to by 'packet',
204          * 'left' extra ones at the end */
205         if (s->packet != pkt) /* len > 0 */
206                 {
207                 memmove(pkt, s->packet, len+left);
208                 s->packet = pkt;
209                 rb->offset = len + align;
210                 }
211
212         if (n > (int)(rb->len - rb->offset)) /* does not happen */
213                 {
214                 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
215                 return -1;
216                 }
217
218         if (!s->read_ahead)
219                 /* ignore max parameter */
220                 max = n;
221         else
222                 {
223                 if (max < n)
224                         max = n;
225                 if (max > (int)(rb->len - rb->offset))
226                         max = rb->len - rb->offset;
227                 }
228
229         while (left < n)
230                 {
231                 /* Now we have len+left bytes at the front of s->s3->rbuf.buf
232                  * and need to read in more until we have len+n (up to
233                  * len+max if possible) */
234
235                 clear_sys_error();
236                 if (s->rbio != NULL)
237                         {
238                         s->rwstate=SSL_READING;
239                         i=BIO_read(s->rbio,pkt+len+left, max-left);
240                         }
241                 else
242                         {
243                         SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
244                         i = -1;
245                         }
246
247                 if (i <= 0)
248                         {
249                         rb->left = left;
250                         if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
251                             SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
252                                 if (len+left == 0)
253                                         ssl3_release_read_buffer(s);
254                         return(i);
255                         }
256                 left+=i;
257                 /* reads should *never* span multiple packets for DTLS because
258                  * the underlying transport protocol is message oriented as opposed
259                  * to byte oriented as in the TLS case. */
260                 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER)
261                         {
262                         if (n > left)
263                                 n = left; /* makes the while condition false */
264                         }
265                 }
266
267         /* done reading, now the book-keeping */
268         rb->offset += n;
269         rb->left = left - n;
270         s->packet_length += n;
271         s->rwstate=SSL_NOTHING;
272         return(n);
273         }
274
275 /* Call this to get a new input record.
276  * It will return <= 0 if more data is needed, normally due to an error
277  * or non-blocking IO.
278  * When it finishes, one packet has been decoded and can be found in
279  * ssl->s3->rrec.type    - is the type of record
280  * ssl->s3->rrec.data,   - data
281  * ssl->s3->rrec.length, - number of bytes
282  */
283 /* used only by ssl3_read_bytes */
284 static int ssl3_get_record(SSL *s)
285         {
286         int ssl_major,ssl_minor,al;
287         int enc_err,n,i,ret= -1;
288         SSL3_RECORD *rr;
289         SSL_SESSION *sess;
290         unsigned char *p;
291         unsigned char md[EVP_MAX_MD_SIZE];
292         short version;
293         int mac_size;
294         int clear=0;
295         size_t extra;
296         int decryption_failed_or_bad_record_mac = 0;
297         unsigned char *mac = NULL;
298
299         rr= &(s->s3->rrec);
300         sess=s->session;
301
302         if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
303                 extra=SSL3_RT_MAX_EXTRA;
304         else
305                 extra=0;
306         if (extra && !s->s3->init_extra)
307                 {
308                 /* An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER
309                  * set after ssl3_setup_buffers() was done */
310                 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
311                 return -1;
312                 }
313
314 again:
315         /* check if we have the header */
316         if (    (s->rstate != SSL_ST_READ_BODY) ||
317                 (s->packet_length < SSL3_RT_HEADER_LENGTH)) 
318                 {
319                 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
320                 if (n <= 0) return(n); /* error or non-blocking */
321                 s->rstate=SSL_ST_READ_BODY;
322
323                 p=s->packet;
324
325                 /* Pull apart the header into the SSL3_RECORD */
326                 rr->type= *(p++);
327                 ssl_major= *(p++);
328                 ssl_minor= *(p++);
329                 version=(ssl_major<<8)|ssl_minor;
330                 n2s(p,rr->length);
331 #if 0
332 fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length);
333 #endif
334
335                 /* Lets check version */
336                 if (!s->first_packet)
337                         {
338                         if (version != s->version)
339                                 {
340                                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
341                                 if ((s->version & 0xFF00) == (version & 0xFF00))
342                                         /* Send back error using their minor version number :-) */
343                                         s->version = (unsigned short)version;
344                                 al=SSL_AD_PROTOCOL_VERSION;
345                                 goto f_err;
346                                 }
347                         }
348
349                 if ((version>>8) != SSL3_VERSION_MAJOR)
350                         {
351                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
352                         goto err;
353                         }
354
355                 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH)
356                         {
357                         al=SSL_AD_RECORD_OVERFLOW;
358                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
359                         goto f_err;
360                         }
361
362                 /* now s->rstate == SSL_ST_READ_BODY */
363                 }
364
365         /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
366
367         if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
368                 {
369                 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
370                 i=rr->length;
371                 n=ssl3_read_n(s,i,i,1);
372                 if (n <= 0) return(n); /* error or non-blocking io */
373                 /* now n == rr->length,
374                  * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
375                 }
376
377         s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
378
379         /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
380          * and we have that many bytes in s->packet
381          */
382         rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
383
384         /* ok, we can now read from 's->packet' data into 'rr'
385          * rr->input points at rr->length bytes, which
386          * need to be copied into rr->data by either
387          * the decryption or by the decompression
388          * When the data is 'copied' into the rr->data buffer,
389          * rr->input will be pointed at the new buffer */ 
390
391         /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
392          * rr->length bytes of encrypted compressed stuff. */
393
394         /* check is not needed I believe */
395         if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
396                 {
397                 al=SSL_AD_RECORD_OVERFLOW;
398                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
399                 goto f_err;
400                 }
401
402         /* decrypt in place in 'rr->input' */
403         rr->data=rr->input;
404
405         enc_err = s->method->ssl3_enc->enc(s,0);
406         if (enc_err <= 0)
407                 {
408                 if (enc_err == 0)
409                         /* SSLerr() and ssl3_send_alert() have been called */
410                         goto err;
411
412                 /* Otherwise enc_err == -1, which indicates bad padding
413                  * (rec->length has not been changed in this case).
414                  * To minimize information leaked via timing, we will perform
415                  * the MAC computation anyway. */
416                 decryption_failed_or_bad_record_mac = 1;
417                 }
418
419 #ifdef TLS_DEBUG
420 printf("dec %d\n",rr->length);
421 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
422 printf("\n");
423 #endif
424
425         /* r->length is now the compressed data plus mac */
426         if (    (sess == NULL) ||
427                 (s->enc_read_ctx == NULL) ||
428                 (EVP_MD_CTX_md(s->read_hash) == NULL))
429                 clear=1;
430
431         if (!clear)
432                 {
433                 /* !clear => s->read_hash != NULL => mac_size != -1 */
434                 mac_size=EVP_MD_CTX_size(s->read_hash);
435                 OPENSSL_assert(mac_size >= 0);
436
437                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
438                         {
439 #if 0 /* OK only for stream ciphers (then rr->length is visible from ciphertext anyway) */
440                         al=SSL_AD_RECORD_OVERFLOW;
441                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG);
442                         goto f_err;
443 #else
444                         decryption_failed_or_bad_record_mac = 1;
445 #endif                  
446                         }
447                 /* check the MAC for rr->input (it's in mac_size bytes at the tail) */
448                 if (rr->length >= (unsigned int)mac_size)
449                         {
450                         rr->length -= mac_size;
451                         mac = &rr->data[rr->length];
452                         }
453                 else
454                         {
455                         /* record (minus padding) is too short to contain a MAC */
456 #if 0 /* OK only for stream ciphers */
457                         al=SSL_AD_DECODE_ERROR;
458                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
459                         goto f_err;
460 #else
461                         decryption_failed_or_bad_record_mac = 1;
462                         rr->length = 0;
463 #endif
464                         }
465                 i=s->method->ssl3_enc->mac(s,md,0);
466                 if (i < 0 || mac == NULL || memcmp(md, mac, (size_t)mac_size) != 0)
467                         {
468                         decryption_failed_or_bad_record_mac = 1;
469                         }
470                 }
471
472         if (decryption_failed_or_bad_record_mac)
473                 {
474                 /* A separate 'decryption_failed' alert was introduced with TLS 1.0,
475                  * SSL 3.0 only has 'bad_record_mac'.  But unless a decryption
476                  * failure is directly visible from the ciphertext anyway,
477                  * we should not reveal which kind of error occured -- this
478                  * might become visible to an attacker (e.g. via a logfile) */
479                 al=SSL_AD_BAD_RECORD_MAC;
480                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
481                 goto f_err;
482                 }
483
484         /* r->length is now just compressed */
485         if (s->expand != NULL)
486                 {
487                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
488                         {
489                         al=SSL_AD_RECORD_OVERFLOW;
490                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
491                         goto f_err;
492                         }
493                 if (!ssl3_do_uncompress(s))
494                         {
495                         al=SSL_AD_DECOMPRESSION_FAILURE;
496                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
497                         goto f_err;
498                         }
499                 }
500
501         if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
502                 {
503                 al=SSL_AD_RECORD_OVERFLOW;
504                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
505                 goto f_err;
506                 }
507
508         rr->off=0;
509         /* So at this point the following is true
510          * ssl->s3->rrec.type   is the type of record
511          * ssl->s3->rrec.length == number of bytes in record
512          * ssl->s3->rrec.off    == offset to first valid byte
513          * ssl->s3->rrec.data   == where to take bytes from, increment
514          *                         after use :-).
515          */
516
517         /* we have pulled in a full packet so zero things */
518         s->packet_length=0;
519
520         /* just read a 0 length packet */
521         if (rr->length == 0) goto again;
522
523 #if 0
524 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length);
525 #endif
526
527         return(1);
528
529 f_err:
530         ssl3_send_alert(s,SSL3_AL_FATAL,al);
531 err:
532         return(ret);
533         }
534
535 int ssl3_do_uncompress(SSL *ssl)
536         {
537 #ifndef OPENSSL_NO_COMP
538         int i;
539         SSL3_RECORD *rr;
540
541         rr= &(ssl->s3->rrec);
542         i=COMP_expand_block(ssl->expand,rr->comp,
543                 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
544         if (i < 0)
545                 return(0);
546         else
547                 rr->length=i;
548         rr->data=rr->comp;
549 #endif
550         return(1);
551         }
552
553 int ssl3_do_compress(SSL *ssl)
554         {
555 #ifndef OPENSSL_NO_COMP
556         int i;
557         SSL3_RECORD *wr;
558
559         wr= &(ssl->s3->wrec);
560         i=COMP_compress_block(ssl->compress,wr->data,
561                 SSL3_RT_MAX_COMPRESSED_LENGTH,
562                 wr->input,(int)wr->length);
563         if (i < 0)
564                 return(0);
565         else
566                 wr->length=i;
567
568         wr->input=wr->data;
569 #endif
570         return(1);
571         }
572
573 /* Call this to write data in records of type 'type'
574  * It will return <= 0 if not all data has been sent or non-blocking IO.
575  */
576 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
577         {
578         const unsigned char *buf=buf_;
579         unsigned int tot,n,nw;
580         int i;
581
582         s->rwstate=SSL_NOTHING;
583         tot=s->s3->wnum;
584         s->s3->wnum=0;
585
586         if (SSL_in_init(s) && !s->in_handshake)
587                 {
588                 i=s->handshake_func(s);
589                 if (i < 0) return(i);
590                 if (i == 0)
591                         {
592                         SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
593                         return -1;
594                         }
595                 }
596
597         n=(len-tot);
598         for (;;)
599                 {
600                 if (n > s->max_send_fragment)
601                         nw=s->max_send_fragment;
602                 else
603                         nw=n;
604
605                 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
606                 if (i <= 0)
607                         {
608                         s->s3->wnum=tot;
609                         return i;
610                         }
611
612                 if ((i == (int)n) ||
613                         (type == SSL3_RT_APPLICATION_DATA &&
614                          (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
615                         {
616                         /* next chunk of data should get another prepended empty fragment
617                          * in ciphersuites with known-IV weakness: */
618                         s->s3->empty_fragment_done = 0;
619                         
620                         return tot+i;
621                         }
622
623                 n-=i;
624                 tot+=i;
625                 }
626         }
627
628 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
629                          unsigned int len, int create_empty_fragment)
630         {
631         unsigned char *p,*plen;
632         int i,mac_size,clear=0;
633         int prefix_len=0;
634         int eivlen;
635         long align=0;
636         SSL3_RECORD *wr;
637         SSL3_BUFFER *wb=&(s->s3->wbuf);
638         SSL_SESSION *sess;
639
640         if (wb->buf == NULL)
641                 if (!ssl3_setup_write_buffer(s))
642                         return -1;
643
644         /* first check if there is a SSL3_BUFFER still being written
645          * out.  This will happen with non blocking IO */
646         if (wb->left != 0)
647                 return(ssl3_write_pending(s,type,buf,len));
648
649         /* If we have an alert to send, lets send it */
650         if (s->s3->alert_dispatch)
651                 {
652                 i=s->method->ssl_dispatch_alert(s);
653                 if (i <= 0)
654                         return(i);
655                 /* if it went, fall through and send more stuff */
656                 }
657
658         if (len == 0 && !create_empty_fragment)
659                 return 0;
660
661         wr= &(s->s3->wrec);
662         sess=s->session;
663
664         if (    (sess == NULL) ||
665                 (s->enc_write_ctx == NULL) ||
666                 (EVP_MD_CTX_md(s->write_hash) == NULL))
667                 clear=1;
668
669         if (clear)
670                 mac_size=0;
671         else
672                 {
673                 mac_size=EVP_MD_CTX_size(s->write_hash);
674                 if (mac_size < 0)
675                         goto err;
676                 }
677
678         /* 'create_empty_fragment' is true only when this function calls itself */
679         if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
680                 {
681                 /* countermeasure against known-IV weakness in CBC ciphersuites
682                  * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
683
684                 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
685                         {
686                         /* recursive function call with 'create_empty_fragment' set;
687                          * this prepares and buffers the data for an empty fragment
688                          * (these 'prefix_len' bytes are sent out later
689                          * together with the actual payload) */
690                         prefix_len = do_ssl3_write(s, type, buf, 0, 1);
691                         if (prefix_len <= 0)
692                                 goto err;
693
694                         if (prefix_len >
695                 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD))
696                                 {
697                                 /* insufficient space */
698                                 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
699                                 goto err;
700                                 }
701                         }
702                 
703                 s->s3->empty_fragment_done = 1;
704                 }
705
706         if (create_empty_fragment)
707                 {
708 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
709                 /* extra fragment would be couple of cipher blocks,
710                  * which would be multiple of SSL3_ALIGN_PAYLOAD, so
711                  * if we want to align the real payload, then we can
712                  * just pretent we simply have two headers. */
713                 align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH;
714                 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
715 #endif
716                 p = wb->buf + align;
717                 wb->offset  = align;
718                 }
719         else if (prefix_len)
720                 {
721                 p = wb->buf + wb->offset + prefix_len;
722                 }
723         else
724                 {
725 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
726                 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH;
727                 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
728 #endif
729                 p = wb->buf + align;
730                 wb->offset  = align;
731                 }
732
733         /* write the header */
734
735         *(p++)=type&0xff;
736         wr->type=type;
737
738         *(p++)=(s->version>>8);
739         *(p++)=s->version&0xff;
740
741         /* field where we are to write out packet length */
742         plen=p; 
743         p+=2;
744         /* Explicit IV length, block ciphers and TLS version 1.1 or later */
745         if (s->enc_write_ctx && s->version >= TLS1_1_VERSION)
746                 {
747                 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
748                 if (mode == EVP_CIPH_CBC_MODE)
749                         {
750                         eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
751                         if (eivlen <= 1)
752                                 eivlen = 0;
753                         }
754                 /* Need explicit part of IV for GCM mode */
755                 else if (mode == EVP_CIPH_GCM_MODE)
756                         eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
757                 }
758         else 
759                 eivlen = 0;
760
761         /* lets setup the record stuff. */
762         wr->data=p + eivlen;
763         wr->length=(int)len;
764         wr->input=(unsigned char *)buf;
765
766         /* we now 'read' from wr->input, wr->length bytes into
767          * wr->data */
768
769         /* first we compress */
770         if (s->compress != NULL)
771                 {
772                 if (!ssl3_do_compress(s))
773                         {
774                         SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
775                         goto err;
776                         }
777                 }
778         else
779                 {
780                 memcpy(wr->data,wr->input,wr->length);
781                 wr->input=wr->data;
782                 }
783
784         /* we should still have the output to wr->data and the input
785          * from wr->input.  Length should be wr->length.
786          * wr->data still points in the wb->buf */
787
788         if (mac_size != 0)
789                 {
790                 if (s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0)
791                         goto err;
792                 wr->length+=mac_size;
793                 }
794
795         wr->input=p;
796         wr->data=p;
797
798         if (eivlen)
799                 {
800         /*      if (RAND_pseudo_bytes(p, eivlen) <= 0)
801                         goto err; */
802                 wr->length += eivlen;
803                 }
804
805         /* ssl3_enc can only have an error on read */
806         s->method->ssl3_enc->enc(s,1);
807
808         /* record length after mac and block padding */
809         s2n(wr->length,plen);
810
811         /* we should now have
812          * wr->data pointing to the encrypted data, which is
813          * wr->length long */
814         wr->type=type; /* not needed but helps for debugging */
815         wr->length+=SSL3_RT_HEADER_LENGTH;
816
817         if (create_empty_fragment)
818                 {
819                 /* we are in a recursive call;
820                  * just return the length, don't write out anything here
821                  */
822                 return wr->length;
823                 }
824
825         /* now let's set up wb */
826         wb->left = prefix_len + wr->length;
827
828         /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
829         s->s3->wpend_tot=len;
830         s->s3->wpend_buf=buf;
831         s->s3->wpend_type=type;
832         s->s3->wpend_ret=len;
833
834         /* we now just need to write the buffer */
835         return ssl3_write_pending(s,type,buf,len);
836 err:
837         return -1;
838         }
839
840 /* if s->s3->wbuf.left != 0, we need to call this */
841 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
842         unsigned int len)
843         {
844         int i;
845         SSL3_BUFFER *wb=&(s->s3->wbuf);
846
847 /* XXXX */
848         if ((s->s3->wpend_tot > (int)len)
849                 || ((s->s3->wpend_buf != buf) &&
850                         !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
851                 || (s->s3->wpend_type != type))
852                 {
853                 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
854                 return(-1);
855                 }
856
857         for (;;)
858                 {
859                 clear_sys_error();
860                 if (s->wbio != NULL)
861                         {
862                         s->rwstate=SSL_WRITING;
863                         i=BIO_write(s->wbio,
864                                 (char *)&(wb->buf[wb->offset]),
865                                 (unsigned int)wb->left);
866                         }
867                 else
868                         {
869                         SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
870                         i= -1;
871                         }
872                 if (i == wb->left)
873                         {
874                         wb->left=0;
875                         wb->offset+=i;
876                         if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
877                             SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
878                                 ssl3_release_write_buffer(s);
879                         s->rwstate=SSL_NOTHING;
880                         return(s->s3->wpend_ret);
881                         }
882                 else if (i <= 0) {
883                         if (s->version == DTLS1_VERSION ||
884                             s->version == DTLS1_BAD_VER) {
885                                 /* For DTLS, just drop it. That's kind of the whole
886                                    point in using a datagram service */
887                                 wb->left = 0;
888                         }
889                         return(i);
890                 }
891                 wb->offset+=i;
892                 wb->left-=i;
893                 }
894         }
895
896 /* Return up to 'len' payload bytes received in 'type' records.
897  * 'type' is one of the following:
898  *
899  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
900  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
901  *   -  0 (during a shutdown, no data has to be returned)
902  *
903  * If we don't have stored data to work from, read a SSL/TLS record first
904  * (possibly multiple records if we still don't have anything to return).
905  *
906  * This function must handle any surprises the peer may have for us, such as
907  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
908  * a surprise, but handled as if it were), or renegotiation requests.
909  * Also if record payloads contain fragments too small to process, we store
910  * them until there is enough for the respective protocol (the record protocol
911  * may use arbitrary fragmentation and even interleaving):
912  *     Change cipher spec protocol
913  *             just 1 byte needed, no need for keeping anything stored
914  *     Alert protocol
915  *             2 bytes needed (AlertLevel, AlertDescription)
916  *     Handshake protocol
917  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
918  *             to detect unexpected Client Hello and Hello Request messages
919  *             here, anything else is handled by higher layers
920  *     Application data protocol
921  *             none of our business
922  */
923 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
924         {
925         int al,i,j,ret;
926         unsigned int n;
927         SSL3_RECORD *rr;
928         void (*cb)(const SSL *ssl,int type2,int val)=NULL;
929
930         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
931                 if (!ssl3_setup_read_buffer(s))
932                         return(-1);
933
934         if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) ||
935             (peek && (type != SSL3_RT_APPLICATION_DATA)))
936                 {
937                 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
938                 return -1;
939                 }
940
941         if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
942                 /* (partially) satisfy request from storage */
943                 {
944                 unsigned char *src = s->s3->handshake_fragment;
945                 unsigned char *dst = buf;
946                 unsigned int k;
947
948                 /* peek == 0 */
949                 n = 0;
950                 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
951                         {
952                         *dst++ = *src++;
953                         len--; s->s3->handshake_fragment_len--;
954                         n++;
955                         }
956                 /* move any remaining fragment bytes: */
957                 for (k = 0; k < s->s3->handshake_fragment_len; k++)
958                         s->s3->handshake_fragment[k] = *src++;
959                 return n;
960         }
961
962         /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
963
964         if (!s->in_handshake && SSL_in_init(s))
965                 {
966                 /* type == SSL3_RT_APPLICATION_DATA */
967                 i=s->handshake_func(s);
968                 if (i < 0) return(i);
969                 if (i == 0)
970                         {
971                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
972                         return(-1);
973                         }
974                 }
975 start:
976         s->rwstate=SSL_NOTHING;
977
978         /* s->s3->rrec.type         - is the type of record
979          * s->s3->rrec.data,    - data
980          * s->s3->rrec.off,     - offset into 'data' for next read
981          * s->s3->rrec.length,  - number of bytes. */
982         rr = &(s->s3->rrec);
983
984         /* get new packet if necessary */
985         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
986                 {
987                 ret=ssl3_get_record(s);
988                 if (ret <= 0) return(ret);
989                 }
990
991         /* we now have a packet which can be read and processed */
992
993         if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
994                                        * reset by ssl3_get_finished */
995                 && (rr->type != SSL3_RT_HANDSHAKE))
996                 {
997                 al=SSL_AD_UNEXPECTED_MESSAGE;
998                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
999                 goto f_err;
1000                 }
1001
1002         /* If the other end has shut down, throw anything we read away
1003          * (even in 'peek' mode) */
1004         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
1005                 {
1006                 rr->length=0;
1007                 s->rwstate=SSL_NOTHING;
1008                 return(0);
1009                 }
1010
1011
1012         if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
1013                 {
1014                 /* make sure that we are not getting application data when we
1015                  * are doing a handshake for the first time */
1016                 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
1017                         (s->enc_read_ctx == NULL))
1018                         {
1019                         al=SSL_AD_UNEXPECTED_MESSAGE;
1020                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
1021                         goto f_err;
1022                         }
1023
1024                 if (len <= 0) return(len);
1025
1026                 if ((unsigned int)len > rr->length)
1027                         n = rr->length;
1028                 else
1029                         n = (unsigned int)len;
1030
1031                 memcpy(buf,&(rr->data[rr->off]),n);
1032                 if (!peek)
1033                         {
1034                         rr->length-=n;
1035                         rr->off+=n;
1036                         if (rr->length == 0)
1037                                 {
1038                                 s->rstate=SSL_ST_READ_HEADER;
1039                                 rr->off=0;
1040                                 if (s->mode & SSL_MODE_RELEASE_BUFFERS)
1041                                         ssl3_release_read_buffer(s);
1042                                 }
1043                         }
1044                 return(n);
1045                 }
1046
1047
1048         /* If we get here, then type != rr->type; if we have a handshake
1049          * message, then it was unexpected (Hello Request or Client Hello). */
1050
1051         /* In case of record types for which we have 'fragment' storage,
1052          * fill that so that we can process the data at a fixed place.
1053          */
1054                 {
1055                 unsigned int dest_maxlen = 0;
1056                 unsigned char *dest = NULL;
1057                 unsigned int *dest_len = NULL;
1058
1059                 if (rr->type == SSL3_RT_HANDSHAKE)
1060                         {
1061                         dest_maxlen = sizeof s->s3->handshake_fragment;
1062                         dest = s->s3->handshake_fragment;
1063                         dest_len = &s->s3->handshake_fragment_len;
1064                         }
1065                 else if (rr->type == SSL3_RT_ALERT)
1066                         {
1067                         dest_maxlen = sizeof s->s3->alert_fragment;
1068                         dest = s->s3->alert_fragment;
1069                         dest_len = &s->s3->alert_fragment_len;
1070                         }
1071
1072                 if (dest_maxlen > 0)
1073                         {
1074                         n = dest_maxlen - *dest_len; /* available space in 'dest' */
1075                         if (rr->length < n)
1076                                 n = rr->length; /* available bytes */
1077
1078                         /* now move 'n' bytes: */
1079                         while (n-- > 0)
1080                                 {
1081                                 dest[(*dest_len)++] = rr->data[rr->off++];
1082                                 rr->length--;
1083                                 }
1084
1085                         if (*dest_len < dest_maxlen)
1086                                 goto start; /* fragment was too small */
1087                         }
1088                 }
1089
1090         /* s->s3->handshake_fragment_len == 4  iff  rr->type == SSL3_RT_HANDSHAKE;
1091          * s->s3->alert_fragment_len == 2      iff  rr->type == SSL3_RT_ALERT.
1092          * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
1093
1094         /* If we are a client, check for an incoming 'Hello Request': */
1095         if ((!s->server) &&
1096                 (s->s3->handshake_fragment_len >= 4) &&
1097                 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1098                 (s->session != NULL) && (s->session->cipher != NULL))
1099                 {
1100                 s->s3->handshake_fragment_len = 0;
1101
1102                 if ((s->s3->handshake_fragment[1] != 0) ||
1103                         (s->s3->handshake_fragment[2] != 0) ||
1104                         (s->s3->handshake_fragment[3] != 0))
1105                         {
1106                         al=SSL_AD_DECODE_ERROR;
1107                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1108                         goto f_err;
1109                         }
1110
1111                 if (s->msg_callback)
1112                         s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
1113
1114                 if (SSL_is_init_finished(s) &&
1115                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1116                         !s->s3->renegotiate)
1117                         {
1118                         ssl3_renegotiate(s);
1119                         if (ssl3_renegotiate_check(s))
1120                                 {
1121                                 i=s->handshake_func(s);
1122                                 if (i < 0) return(i);
1123                                 if (i == 0)
1124                                         {
1125                                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1126                                         return(-1);
1127                                         }
1128
1129                                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1130                                         {
1131                                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1132                                                 {
1133                                                 BIO *bio;
1134                                                 /* In the case where we try to read application data,
1135                                                  * but we trigger an SSL handshake, we return -1 with
1136                                                  * the retry option set.  Otherwise renegotiation may
1137                                                  * cause nasty problems in the blocking world */
1138                                                 s->rwstate=SSL_READING;
1139                                                 bio=SSL_get_rbio(s);
1140                                                 BIO_clear_retry_flags(bio);
1141                                                 BIO_set_retry_read(bio);
1142                                                 return(-1);
1143                                                 }
1144                                         }
1145                                 }
1146                         }
1147                 /* we either finished a handshake or ignored the request,
1148                  * now try again to obtain the (application) data we were asked for */
1149                 goto start;
1150                 }
1151         /* If we are a server and get a client hello when renegotiation isn't
1152          * allowed send back a no renegotiation alert and carry on.
1153          * WARNING: experimental code, needs reviewing (steve)
1154          */
1155         if (s->server &&
1156                 SSL_is_init_finished(s) &&
1157                 !s->s3->send_connection_binding &&
1158                 (s->version > SSL3_VERSION) &&
1159                 (s->s3->handshake_fragment_len >= 4) &&
1160                 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1161                 (s->session != NULL) && (s->session->cipher != NULL) &&
1162                 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1163                 
1164                 {
1165                 /*s->s3->handshake_fragment_len = 0;*/
1166                 rr->length = 0;
1167                 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1168                 goto start;
1169                 }
1170         if (s->s3->alert_fragment_len >= 2)
1171                 {
1172                 int alert_level = s->s3->alert_fragment[0];
1173                 int alert_descr = s->s3->alert_fragment[1];
1174
1175                 s->s3->alert_fragment_len = 0;
1176
1177                 if (s->msg_callback)
1178                         s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1179
1180                 if (s->info_callback != NULL)
1181                         cb=s->info_callback;
1182                 else if (s->ctx->info_callback != NULL)
1183                         cb=s->ctx->info_callback;
1184
1185                 if (cb != NULL)
1186                         {
1187                         j = (alert_level << 8) | alert_descr;
1188                         cb(s, SSL_CB_READ_ALERT, j);
1189                         }
1190
1191                 if (alert_level == 1) /* warning */
1192                         {
1193                         s->s3->warn_alert = alert_descr;
1194                         if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1195                                 {
1196                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1197                                 return(0);
1198                                 }
1199                         /* This is a warning but we receive it if we requested
1200                          * renegotiation and the peer denied it. Terminate with
1201                          * a fatal alert because if application tried to
1202                          * renegotiatie it presumably had a good reason and
1203                          * expects it to succeed.
1204                          *
1205                          * In future we might have a renegotiation where we
1206                          * don't care if the peer refused it where we carry on.
1207                          */
1208                         else if (alert_descr == SSL_AD_NO_RENEGOTIATION)
1209                                 {
1210                                 al = SSL_AD_HANDSHAKE_FAILURE;
1211                                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION);
1212                                 goto f_err;
1213                                 }
1214 #ifdef SSL_AD_MISSING_SRP_USERNAME
1215                         else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME)
1216                                 return(0);
1217 #endif
1218                         }
1219                 else if (alert_level == 2) /* fatal */
1220                         {
1221                         char tmp[16];
1222
1223                         s->rwstate=SSL_NOTHING;
1224                         s->s3->fatal_alert = alert_descr;
1225                         SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1226                         BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1227                         ERR_add_error_data(2,"SSL alert number ",tmp);
1228                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1229                         SSL_CTX_remove_session(s->ctx,s->session);
1230                         return(0);
1231                         }
1232                 else
1233                         {
1234                         al=SSL_AD_ILLEGAL_PARAMETER;
1235                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1236                         goto f_err;
1237                         }
1238
1239                 goto start;
1240                 }
1241
1242         if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1243                 {
1244                 s->rwstate=SSL_NOTHING;
1245                 rr->length=0;
1246                 return(0);
1247                 }
1248
1249         if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1250                 {
1251                 /* 'Change Cipher Spec' is just a single byte, so we know
1252                  * exactly what the record payload has to look like */
1253                 if (    (rr->length != 1) || (rr->off != 0) ||
1254                         (rr->data[0] != SSL3_MT_CCS))
1255                         {
1256                         al=SSL_AD_ILLEGAL_PARAMETER;
1257                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1258                         goto f_err;
1259                         }
1260
1261                 /* Check we have a cipher to change to */
1262                 if (s->s3->tmp.new_cipher == NULL)
1263                         {
1264                         al=SSL_AD_UNEXPECTED_MESSAGE;
1265                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1266                         goto f_err;
1267                         }
1268
1269                 rr->length=0;
1270
1271                 if (s->msg_callback)
1272                         s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1273
1274                 s->s3->change_cipher_spec=1;
1275                 if (!ssl3_do_change_cipher_spec(s))
1276                         goto err;
1277                 else
1278                         goto start;
1279                 }
1280
1281         /* Unexpected handshake message (Client Hello, or protocol violation) */
1282         if ((s->s3->handshake_fragment_len >= 4) &&     !s->in_handshake)
1283                 {
1284                 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1285                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1286                         {
1287 #if 0 /* worked only because C operator preferences are not as expected (and
1288        * because this is not really needed for clients except for detecting
1289        * protocol violations): */
1290                         s->state=SSL_ST_BEFORE|(s->server)
1291                                 ?SSL_ST_ACCEPT
1292                                 :SSL_ST_CONNECT;
1293 #else
1294                         s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1295 #endif
1296                         s->renegotiate=1;
1297                         s->new_session=1;
1298                         }
1299                 i=s->handshake_func(s);
1300                 if (i < 0) return(i);
1301                 if (i == 0)
1302                         {
1303                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1304                         return(-1);
1305                         }
1306
1307                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1308                         {
1309                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1310                                 {
1311                                 BIO *bio;
1312                                 /* In the case where we try to read application data,
1313                                  * but we trigger an SSL handshake, we return -1 with
1314                                  * the retry option set.  Otherwise renegotiation may
1315                                  * cause nasty problems in the blocking world */
1316                                 s->rwstate=SSL_READING;
1317                                 bio=SSL_get_rbio(s);
1318                                 BIO_clear_retry_flags(bio);
1319                                 BIO_set_retry_read(bio);
1320                                 return(-1);
1321                                 }
1322                         }
1323                 goto start;
1324                 }
1325
1326         switch (rr->type)
1327                 {
1328         default:
1329 #ifndef OPENSSL_NO_TLS
1330                 /* TLS up to v1.1 just ignores unknown message types:
1331                  * TLS v1.2 give an unexpected message alert.
1332                  */
1333                 if (s->version >= TLS1_VERSION && s->version <= TLS1_1_VERSION)
1334                         {
1335                         rr->length = 0;
1336                         goto start;
1337                         }
1338 #endif
1339                 al=SSL_AD_UNEXPECTED_MESSAGE;
1340                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1341                 goto f_err;
1342         case SSL3_RT_CHANGE_CIPHER_SPEC:
1343         case SSL3_RT_ALERT:
1344         case SSL3_RT_HANDSHAKE:
1345                 /* we already handled all of these, with the possible exception
1346                  * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1347                  * should not happen when type != rr->type */
1348                 al=SSL_AD_UNEXPECTED_MESSAGE;
1349                 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1350                 goto f_err;
1351         case SSL3_RT_APPLICATION_DATA:
1352                 /* At this point, we were expecting handshake data,
1353                  * but have application data.  If the library was
1354                  * running inside ssl3_read() (i.e. in_read_app_data
1355                  * is set) and it makes sense to read application data
1356                  * at this point (session renegotiation not yet started),
1357                  * we will indulge it.
1358                  */
1359                 if (s->s3->in_read_app_data &&
1360                         (s->s3->total_renegotiations != 0) &&
1361                         ((
1362                                 (s->state & SSL_ST_CONNECT) &&
1363                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1364                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1365                                 ) || (
1366                                         (s->state & SSL_ST_ACCEPT) &&
1367                                         (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1368                                         (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1369                                         )
1370                                 ))
1371                         {
1372                         s->s3->in_read_app_data=2;
1373                         return(-1);
1374                         }
1375                 else
1376                         {
1377                         al=SSL_AD_UNEXPECTED_MESSAGE;
1378                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1379                         goto f_err;
1380                         }
1381                 }
1382         /* not reached */
1383
1384 f_err:
1385         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1386 err:
1387         return(-1);
1388         }
1389
1390 int ssl3_do_change_cipher_spec(SSL *s)
1391         {
1392         int i;
1393         const char *sender;
1394         int slen;
1395
1396         if (s->state & SSL_ST_ACCEPT)
1397                 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1398         else
1399                 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1400
1401         if (s->s3->tmp.key_block == NULL)
1402                 {
1403                 if (s->session == NULL) 
1404                         {
1405                         /* might happen if dtls1_read_bytes() calls this */
1406                         SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY);
1407                         return (0);
1408                         }
1409
1410                 s->session->cipher=s->s3->tmp.new_cipher;
1411                 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1412                 }
1413
1414         if (!s->method->ssl3_enc->change_cipher_state(s,i))
1415                 return(0);
1416
1417         /* we have to record the message digest at
1418          * this point so we can get it before we read
1419          * the finished message */
1420         if (s->state & SSL_ST_CONNECT)
1421                 {
1422                 sender=s->method->ssl3_enc->server_finished_label;
1423                 slen=s->method->ssl3_enc->server_finished_label_len;
1424                 }
1425         else
1426                 {
1427                 sender=s->method->ssl3_enc->client_finished_label;
1428                 slen=s->method->ssl3_enc->client_finished_label_len;
1429                 }
1430
1431         s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1432                 sender,slen,s->s3->tmp.peer_finish_md);
1433
1434         return(1);
1435         }
1436
1437 int ssl3_send_alert(SSL *s, int level, int desc)
1438         {
1439         /* Map tls/ssl alert value to correct one */
1440         desc=s->method->ssl3_enc->alert_value(desc);
1441         if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1442                 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1443         if (desc < 0) return -1;
1444         /* If a fatal one, remove from cache */
1445         if ((level == 2) && (s->session != NULL))
1446                 SSL_CTX_remove_session(s->ctx,s->session);
1447
1448         s->s3->alert_dispatch=1;
1449         s->s3->send_alert[0]=level;
1450         s->s3->send_alert[1]=desc;
1451         if (s->s3->wbuf.left == 0) /* data still being written out? */
1452                 return s->method->ssl_dispatch_alert(s);
1453         /* else data is still being written out, we will get written
1454          * some time in the future */
1455         return -1;
1456         }
1457
1458 int ssl3_dispatch_alert(SSL *s)
1459         {
1460         int i,j;
1461         void (*cb)(const SSL *ssl,int type,int val)=NULL;
1462
1463         s->s3->alert_dispatch=0;
1464         i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1465         if (i <= 0)
1466                 {
1467                 s->s3->alert_dispatch=1;
1468                 }
1469         else
1470                 {
1471                 /* Alert sent to BIO.  If it is important, flush it now.
1472                  * If the message does not get sent due to non-blocking IO,
1473                  * we will not worry too much. */
1474                 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1475                         (void)BIO_flush(s->wbio);
1476
1477                 if (s->msg_callback)
1478                         s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1479
1480                 if (s->info_callback != NULL)
1481                         cb=s->info_callback;
1482                 else if (s->ctx->info_callback != NULL)
1483                         cb=s->ctx->info_callback;
1484
1485                 if (cb != NULL)
1486                         {
1487                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1488                         cb(s,SSL_CB_WRITE_ALERT,j);
1489                         }
1490                 }
1491         return(i);
1492         }