tap: Define TAP_MANUALMAKE; unbreak building
[dragonfly.git] / crypto / openssl / 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         unsigned mac_size, orig_len;
294         size_t extra;
295
296         rr= &(s->s3->rrec);
297         sess=s->session;
298
299         if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
300                 extra=SSL3_RT_MAX_EXTRA;
301         else
302                 extra=0;
303         if (extra && !s->s3->init_extra)
304                 {
305                 /* An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER
306                  * set after ssl3_setup_buffers() was done */
307                 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
308                 return -1;
309                 }
310
311 again:
312         /* check if we have the header */
313         if (    (s->rstate != SSL_ST_READ_BODY) ||
314                 (s->packet_length < SSL3_RT_HEADER_LENGTH)) 
315                 {
316                 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
317                 if (n <= 0) return(n); /* error or non-blocking */
318                 s->rstate=SSL_ST_READ_BODY;
319
320                 p=s->packet;
321
322                 /* Pull apart the header into the SSL3_RECORD */
323                 rr->type= *(p++);
324                 ssl_major= *(p++);
325                 ssl_minor= *(p++);
326                 version=(ssl_major<<8)|ssl_minor;
327                 n2s(p,rr->length);
328 #if 0
329 fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length);
330 #endif
331
332                 /* Lets check version */
333                 if (!s->first_packet)
334                         {
335                         if (version != s->version)
336                                 {
337                                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
338                                 if ((s->version & 0xFF00) == (version & 0xFF00))
339                                         /* Send back error using their minor version number :-) */
340                                         s->version = (unsigned short)version;
341                                 al=SSL_AD_PROTOCOL_VERSION;
342                                 goto f_err;
343                                 }
344                         }
345
346                 if ((version>>8) != SSL3_VERSION_MAJOR)
347                         {
348                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
349                         goto err;
350                         }
351
352                 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH)
353                         {
354                         al=SSL_AD_RECORD_OVERFLOW;
355                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
356                         goto f_err;
357                         }
358
359                 /* now s->rstate == SSL_ST_READ_BODY */
360                 }
361
362         /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
363
364         if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
365                 {
366                 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
367                 i=rr->length;
368                 n=ssl3_read_n(s,i,i,1);
369                 if (n <= 0) return(n); /* error or non-blocking io */
370                 /* now n == rr->length,
371                  * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
372                 }
373
374         s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
375
376         /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
377          * and we have that many bytes in s->packet
378          */
379         rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
380
381         /* ok, we can now read from 's->packet' data into 'rr'
382          * rr->input points at rr->length bytes, which
383          * need to be copied into rr->data by either
384          * the decryption or by the decompression
385          * When the data is 'copied' into the rr->data buffer,
386          * rr->input will be pointed at the new buffer */ 
387
388         /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
389          * rr->length bytes of encrypted compressed stuff. */
390
391         /* check is not needed I believe */
392         if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
393                 {
394                 al=SSL_AD_RECORD_OVERFLOW;
395                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
396                 goto f_err;
397                 }
398
399         /* decrypt in place in 'rr->input' */
400         rr->data=rr->input;
401         orig_len=rr->length;
402
403         enc_err = s->method->ssl3_enc->enc(s,0);
404         /* enc_err is:
405          *    0: (in non-constant time) if the record is publically invalid.
406          *    1: if the padding is valid
407          *    -1: if the padding is invalid */
408         if (enc_err == 0)
409                 {
410                 al=SSL_AD_DECRYPTION_FAILED;
411                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
412                 goto f_err;
413                 }
414
415 #ifdef TLS_DEBUG
416 printf("dec %d\n",rr->length);
417 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
418 printf("\n");
419 #endif
420
421         /* r->length is now the compressed data plus mac */
422         if ((sess != NULL) &&
423             (s->enc_read_ctx != NULL) &&
424             (EVP_MD_CTX_md(s->read_hash) != NULL))
425                 {
426                 /* s->read_hash != NULL => mac_size != -1 */
427                 unsigned char *mac = NULL;
428                 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
429                 mac_size=EVP_MD_CTX_size(s->read_hash);
430                 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
431
432                 /* orig_len is the length of the record before any padding was
433                  * removed. This is public information, as is the MAC in use,
434                  * therefore we can safely process the record in a different
435                  * amount of time if it's too short to possibly contain a MAC.
436                  */
437                 if (orig_len < mac_size ||
438                     /* CBC records must have a padding length byte too. */
439                     (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
440                      orig_len < mac_size+1))
441                         {
442                         al=SSL_AD_DECODE_ERROR;
443                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
444                         goto f_err;
445                         }
446
447                 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE)
448                         {
449                         /* We update the length so that the TLS header bytes
450                          * can be constructed correctly but we need to extract
451                          * the MAC in constant time from within the record,
452                          * without leaking the contents of the padding bytes.
453                          * */
454                         mac = mac_tmp;
455                         ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
456                         rr->length -= mac_size;
457                         }
458                 else
459                         {
460                         /* In this case there's no padding, so |orig_len|
461                          * equals |rec->length| and we checked that there's
462                          * enough bytes for |mac_size| above. */
463                         rr->length -= mac_size;
464                         mac = &rr->data[rr->length];
465                         }
466
467                 i=s->method->ssl3_enc->mac(s,md,0 /* not send */);
468                 if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
469                         enc_err = -1;
470                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
471                         enc_err = -1;
472                 }
473
474         if (enc_err < 0)
475                 {
476                 /* A separate 'decryption_failed' alert was introduced with TLS 1.0,
477                  * SSL 3.0 only has 'bad_record_mac'.  But unless a decryption
478                  * failure is directly visible from the ciphertext anyway,
479                  * we should not reveal which kind of error occured -- this
480                  * might become visible to an attacker (e.g. via a logfile) */
481                 al=SSL_AD_BAD_RECORD_MAC;
482                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
483                 goto f_err;
484                 }
485
486         /* r->length is now just compressed */
487         if (s->expand != NULL)
488                 {
489                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
490                         {
491                         al=SSL_AD_RECORD_OVERFLOW;
492                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
493                         goto f_err;
494                         }
495                 if (!ssl3_do_uncompress(s))
496                         {
497                         al=SSL_AD_DECOMPRESSION_FAILURE;
498                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
499                         goto f_err;
500                         }
501                 }
502
503         if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
504                 {
505                 al=SSL_AD_RECORD_OVERFLOW;
506                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
507                 goto f_err;
508                 }
509
510         rr->off=0;
511         /* So at this point the following is true
512          * ssl->s3->rrec.type   is the type of record
513          * ssl->s3->rrec.length == number of bytes in record
514          * ssl->s3->rrec.off    == offset to first valid byte
515          * ssl->s3->rrec.data   == where to take bytes from, increment
516          *                         after use :-).
517          */
518
519         /* we have pulled in a full packet so zero things */
520         s->packet_length=0;
521
522         /* just read a 0 length packet */
523         if (rr->length == 0) goto again;
524
525 #if 0
526 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length);
527 #endif
528
529         return(1);
530
531 f_err:
532         ssl3_send_alert(s,SSL3_AL_FATAL,al);
533 err:
534         return(ret);
535         }
536
537 int ssl3_do_uncompress(SSL *ssl)
538         {
539 #ifndef OPENSSL_NO_COMP
540         int i;
541         SSL3_RECORD *rr;
542
543         rr= &(ssl->s3->rrec);
544         i=COMP_expand_block(ssl->expand,rr->comp,
545                 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
546         if (i < 0)
547                 return(0);
548         else
549                 rr->length=i;
550         rr->data=rr->comp;
551 #endif
552         return(1);
553         }
554
555 int ssl3_do_compress(SSL *ssl)
556         {
557 #ifndef OPENSSL_NO_COMP
558         int i;
559         SSL3_RECORD *wr;
560
561         wr= &(ssl->s3->wrec);
562         i=COMP_compress_block(ssl->compress,wr->data,
563                 SSL3_RT_MAX_COMPRESSED_LENGTH,
564                 wr->input,(int)wr->length);
565         if (i < 0)
566                 return(0);
567         else
568                 wr->length=i;
569
570         wr->input=wr->data;
571 #endif
572         return(1);
573         }
574
575 /* Call this to write data in records of type 'type'
576  * It will return <= 0 if not all data has been sent or non-blocking IO.
577  */
578 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
579         {
580         const unsigned char *buf=buf_;
581         unsigned int tot,n,nw;
582         int i;
583
584         s->rwstate=SSL_NOTHING;
585         tot=s->s3->wnum;
586         s->s3->wnum=0;
587
588         if (SSL_in_init(s) && !s->in_handshake)
589                 {
590                 i=s->handshake_func(s);
591                 if (i < 0) return(i);
592                 if (i == 0)
593                         {
594                         SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
595                         return -1;
596                         }
597                 }
598
599         n=(len-tot);
600         for (;;)
601                 {
602                 if (n > s->max_send_fragment)
603                         nw=s->max_send_fragment;
604                 else
605                         nw=n;
606
607                 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
608                 if (i <= 0)
609                         {
610                         s->s3->wnum=tot;
611                         return i;
612                         }
613
614                 if ((i == (int)n) ||
615                         (type == SSL3_RT_APPLICATION_DATA &&
616                          (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
617                         {
618                         /* next chunk of data should get another prepended empty fragment
619                          * in ciphersuites with known-IV weakness: */
620                         s->s3->empty_fragment_done = 0;
621                         
622                         return tot+i;
623                         }
624
625                 n-=i;
626                 tot+=i;
627                 }
628         }
629
630 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
631                          unsigned int len, int create_empty_fragment)
632         {
633         unsigned char *p,*plen;
634         int i,mac_size,clear=0;
635         int prefix_len=0;
636         int eivlen;
637         long align=0;
638         SSL3_RECORD *wr;
639         SSL3_BUFFER *wb=&(s->s3->wbuf);
640         SSL_SESSION *sess;
641
642         if (wb->buf == NULL)
643                 if (!ssl3_setup_write_buffer(s))
644                         return -1;
645
646         /* first check if there is a SSL3_BUFFER still being written
647          * out.  This will happen with non blocking IO */
648         if (wb->left != 0)
649                 return(ssl3_write_pending(s,type,buf,len));
650
651         /* If we have an alert to send, lets send it */
652         if (s->s3->alert_dispatch)
653                 {
654                 i=s->method->ssl_dispatch_alert(s);
655                 if (i <= 0)
656                         return(i);
657                 /* if it went, fall through and send more stuff */
658                 }
659
660         if (len == 0 && !create_empty_fragment)
661                 return 0;
662
663         wr= &(s->s3->wrec);
664         sess=s->session;
665
666         if (    (sess == NULL) ||
667                 (s->enc_write_ctx == NULL) ||
668                 (EVP_MD_CTX_md(s->write_hash) == NULL))
669                 {
670 #if 1
671                 clear=s->enc_write_ctx?0:1;     /* must be AEAD cipher */
672 #else
673                 clear=1;
674 #endif
675                 mac_size=0;
676                 }
677         else
678                 {
679                 mac_size=EVP_MD_CTX_size(s->write_hash);
680                 if (mac_size < 0)
681                         goto err;
682                 }
683
684         /* 'create_empty_fragment' is true only when this function calls itself */
685         if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
686                 {
687                 /* countermeasure against known-IV weakness in CBC ciphersuites
688                  * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
689
690                 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
691                         {
692                         /* recursive function call with 'create_empty_fragment' set;
693                          * this prepares and buffers the data for an empty fragment
694                          * (these 'prefix_len' bytes are sent out later
695                          * together with the actual payload) */
696                         prefix_len = do_ssl3_write(s, type, buf, 0, 1);
697                         if (prefix_len <= 0)
698                                 goto err;
699
700                         if (prefix_len >
701                 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD))
702                                 {
703                                 /* insufficient space */
704                                 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
705                                 goto err;
706                                 }
707                         }
708                 
709                 s->s3->empty_fragment_done = 1;
710                 }
711
712         if (create_empty_fragment)
713                 {
714 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
715                 /* extra fragment would be couple of cipher blocks,
716                  * which would be multiple of SSL3_ALIGN_PAYLOAD, so
717                  * if we want to align the real payload, then we can
718                  * just pretent we simply have two headers. */
719                 align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH;
720                 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
721 #endif
722                 p = wb->buf + align;
723                 wb->offset  = align;
724                 }
725         else if (prefix_len)
726                 {
727                 p = wb->buf + wb->offset + prefix_len;
728                 }
729         else
730                 {
731 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
732                 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH;
733                 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
734 #endif
735                 p = wb->buf + align;
736                 wb->offset  = align;
737                 }
738
739         /* write the header */
740
741         *(p++)=type&0xff;
742         wr->type=type;
743
744         *(p++)=(s->version>>8);
745         /* Some servers hang if iniatial client hello is larger than 256
746          * bytes and record version number > TLS 1.0
747          */
748         if (s->state == SSL3_ST_CW_CLNT_HELLO_B
749                                 && !s->renegotiate
750                                 && TLS1_get_version(s) > TLS1_VERSION)
751                 *(p++) = 0x1;
752         else
753                 *(p++)=s->version&0xff;
754
755         /* field where we are to write out packet length */
756         plen=p; 
757         p+=2;
758         /* Explicit IV length, block ciphers and TLS version 1.1 or later */
759         if (s->enc_write_ctx && s->version >= TLS1_1_VERSION)
760                 {
761                 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
762                 if (mode == EVP_CIPH_CBC_MODE)
763                         {
764                         eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
765                         if (eivlen <= 1)
766                                 eivlen = 0;
767                         }
768                 /* Need explicit part of IV for GCM mode */
769                 else if (mode == EVP_CIPH_GCM_MODE)
770                         eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
771                 else
772                         eivlen = 0;
773                 }
774         else 
775                 eivlen = 0;
776
777         /* lets setup the record stuff. */
778         wr->data=p + eivlen;
779         wr->length=(int)len;
780         wr->input=(unsigned char *)buf;
781
782         /* we now 'read' from wr->input, wr->length bytes into
783          * wr->data */
784
785         /* first we compress */
786         if (s->compress != NULL)
787                 {
788                 if (!ssl3_do_compress(s))
789                         {
790                         SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
791                         goto err;
792                         }
793                 }
794         else
795                 {
796                 memcpy(wr->data,wr->input,wr->length);
797                 wr->input=wr->data;
798                 }
799
800         /* we should still have the output to wr->data and the input
801          * from wr->input.  Length should be wr->length.
802          * wr->data still points in the wb->buf */
803
804         if (mac_size != 0)
805                 {
806                 if (s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0)
807                         goto err;
808                 wr->length+=mac_size;
809                 }
810
811         wr->input=p;
812         wr->data=p;
813
814         if (eivlen)
815                 {
816         /*      if (RAND_pseudo_bytes(p, eivlen) <= 0)
817                         goto err; */
818                 wr->length += eivlen;
819                 }
820
821         /* ssl3_enc can only have an error on read */
822         s->method->ssl3_enc->enc(s,1);
823
824         /* record length after mac and block padding */
825         s2n(wr->length,plen);
826
827         /* we should now have
828          * wr->data pointing to the encrypted data, which is
829          * wr->length long */
830         wr->type=type; /* not needed but helps for debugging */
831         wr->length+=SSL3_RT_HEADER_LENGTH;
832
833         if (create_empty_fragment)
834                 {
835                 /* we are in a recursive call;
836                  * just return the length, don't write out anything here
837                  */
838                 return wr->length;
839                 }
840
841         /* now let's set up wb */
842         wb->left = prefix_len + wr->length;
843
844         /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
845         s->s3->wpend_tot=len;
846         s->s3->wpend_buf=buf;
847         s->s3->wpend_type=type;
848         s->s3->wpend_ret=len;
849
850         /* we now just need to write the buffer */
851         return ssl3_write_pending(s,type,buf,len);
852 err:
853         return -1;
854         }
855
856 /* if s->s3->wbuf.left != 0, we need to call this */
857 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
858         unsigned int len)
859         {
860         int i;
861         SSL3_BUFFER *wb=&(s->s3->wbuf);
862
863 /* XXXX */
864         if ((s->s3->wpend_tot > (int)len)
865                 || ((s->s3->wpend_buf != buf) &&
866                         !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
867                 || (s->s3->wpend_type != type))
868                 {
869                 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
870                 return(-1);
871                 }
872
873         for (;;)
874                 {
875                 clear_sys_error();
876                 if (s->wbio != NULL)
877                         {
878                         s->rwstate=SSL_WRITING;
879                         i=BIO_write(s->wbio,
880                                 (char *)&(wb->buf[wb->offset]),
881                                 (unsigned int)wb->left);
882                         }
883                 else
884                         {
885                         SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
886                         i= -1;
887                         }
888                 if (i == wb->left)
889                         {
890                         wb->left=0;
891                         wb->offset+=i;
892                         if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
893                             SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
894                                 ssl3_release_write_buffer(s);
895                         s->rwstate=SSL_NOTHING;
896                         return(s->s3->wpend_ret);
897                         }
898                 else if (i <= 0) {
899                         if (s->version == DTLS1_VERSION ||
900                             s->version == DTLS1_BAD_VER) {
901                                 /* For DTLS, just drop it. That's kind of the whole
902                                    point in using a datagram service */
903                                 wb->left = 0;
904                         }
905                         return(i);
906                 }
907                 wb->offset+=i;
908                 wb->left-=i;
909                 }
910         }
911
912 /* Return up to 'len' payload bytes received in 'type' records.
913  * 'type' is one of the following:
914  *
915  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
916  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
917  *   -  0 (during a shutdown, no data has to be returned)
918  *
919  * If we don't have stored data to work from, read a SSL/TLS record first
920  * (possibly multiple records if we still don't have anything to return).
921  *
922  * This function must handle any surprises the peer may have for us, such as
923  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
924  * a surprise, but handled as if it were), or renegotiation requests.
925  * Also if record payloads contain fragments too small to process, we store
926  * them until there is enough for the respective protocol (the record protocol
927  * may use arbitrary fragmentation and even interleaving):
928  *     Change cipher spec protocol
929  *             just 1 byte needed, no need for keeping anything stored
930  *     Alert protocol
931  *             2 bytes needed (AlertLevel, AlertDescription)
932  *     Handshake protocol
933  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
934  *             to detect unexpected Client Hello and Hello Request messages
935  *             here, anything else is handled by higher layers
936  *     Application data protocol
937  *             none of our business
938  */
939 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
940         {
941         int al,i,j,ret;
942         unsigned int n;
943         SSL3_RECORD *rr;
944         void (*cb)(const SSL *ssl,int type2,int val)=NULL;
945
946         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
947                 if (!ssl3_setup_read_buffer(s))
948                         return(-1);
949
950         if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) ||
951             (peek && (type != SSL3_RT_APPLICATION_DATA)))
952                 {
953                 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
954                 return -1;
955                 }
956
957         if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
958                 /* (partially) satisfy request from storage */
959                 {
960                 unsigned char *src = s->s3->handshake_fragment;
961                 unsigned char *dst = buf;
962                 unsigned int k;
963
964                 /* peek == 0 */
965                 n = 0;
966                 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
967                         {
968                         *dst++ = *src++;
969                         len--; s->s3->handshake_fragment_len--;
970                         n++;
971                         }
972                 /* move any remaining fragment bytes: */
973                 for (k = 0; k < s->s3->handshake_fragment_len; k++)
974                         s->s3->handshake_fragment[k] = *src++;
975                 return n;
976         }
977
978         /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
979
980         if (!s->in_handshake && SSL_in_init(s))
981                 {
982                 /* type == SSL3_RT_APPLICATION_DATA */
983                 i=s->handshake_func(s);
984                 if (i < 0) return(i);
985                 if (i == 0)
986                         {
987                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
988                         return(-1);
989                         }
990                 }
991 start:
992         s->rwstate=SSL_NOTHING;
993
994         /* s->s3->rrec.type         - is the type of record
995          * s->s3->rrec.data,    - data
996          * s->s3->rrec.off,     - offset into 'data' for next read
997          * s->s3->rrec.length,  - number of bytes. */
998         rr = &(s->s3->rrec);
999
1000         /* get new packet if necessary */
1001         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
1002                 {
1003                 ret=ssl3_get_record(s);
1004                 if (ret <= 0) return(ret);
1005                 }
1006
1007         /* we now have a packet which can be read and processed */
1008
1009         if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
1010                                        * reset by ssl3_get_finished */
1011                 && (rr->type != SSL3_RT_HANDSHAKE))
1012                 {
1013                 al=SSL_AD_UNEXPECTED_MESSAGE;
1014                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
1015                 goto f_err;
1016                 }
1017
1018         /* If the other end has shut down, throw anything we read away
1019          * (even in 'peek' mode) */
1020         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
1021                 {
1022                 rr->length=0;
1023                 s->rwstate=SSL_NOTHING;
1024                 return(0);
1025                 }
1026
1027
1028         if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
1029                 {
1030                 /* make sure that we are not getting application data when we
1031                  * are doing a handshake for the first time */
1032                 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
1033                         (s->enc_read_ctx == NULL))
1034                         {
1035                         al=SSL_AD_UNEXPECTED_MESSAGE;
1036                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
1037                         goto f_err;
1038                         }
1039
1040                 if (len <= 0) return(len);
1041
1042                 if ((unsigned int)len > rr->length)
1043                         n = rr->length;
1044                 else
1045                         n = (unsigned int)len;
1046
1047                 memcpy(buf,&(rr->data[rr->off]),n);
1048                 if (!peek)
1049                         {
1050                         rr->length-=n;
1051                         rr->off+=n;
1052                         if (rr->length == 0)
1053                                 {
1054                                 s->rstate=SSL_ST_READ_HEADER;
1055                                 rr->off=0;
1056                                 if (s->mode & SSL_MODE_RELEASE_BUFFERS)
1057                                         ssl3_release_read_buffer(s);
1058                                 }
1059                         }
1060                 return(n);
1061                 }
1062
1063
1064         /* If we get here, then type != rr->type; if we have a handshake
1065          * message, then it was unexpected (Hello Request or Client Hello). */
1066
1067         /* In case of record types for which we have 'fragment' storage,
1068          * fill that so that we can process the data at a fixed place.
1069          */
1070                 {
1071                 unsigned int dest_maxlen = 0;
1072                 unsigned char *dest = NULL;
1073                 unsigned int *dest_len = NULL;
1074
1075                 if (rr->type == SSL3_RT_HANDSHAKE)
1076                         {
1077                         dest_maxlen = sizeof s->s3->handshake_fragment;
1078                         dest = s->s3->handshake_fragment;
1079                         dest_len = &s->s3->handshake_fragment_len;
1080                         }
1081                 else if (rr->type == SSL3_RT_ALERT)
1082                         {
1083                         dest_maxlen = sizeof s->s3->alert_fragment;
1084                         dest = s->s3->alert_fragment;
1085                         dest_len = &s->s3->alert_fragment_len;
1086                         }
1087 #ifndef OPENSSL_NO_HEARTBEATS
1088                 else if (rr->type == TLS1_RT_HEARTBEAT)
1089                         {
1090                         tls1_process_heartbeat(s);
1091
1092                         /* Exit and notify application to read again */
1093                         rr->length = 0;
1094                         s->rwstate=SSL_READING;
1095                         BIO_clear_retry_flags(SSL_get_rbio(s));
1096                         BIO_set_retry_read(SSL_get_rbio(s));
1097                         return(-1);
1098                         }
1099 #endif
1100
1101                 if (dest_maxlen > 0)
1102                         {
1103                         n = dest_maxlen - *dest_len; /* available space in 'dest' */
1104                         if (rr->length < n)
1105                                 n = rr->length; /* available bytes */
1106
1107                         /* now move 'n' bytes: */
1108                         while (n-- > 0)
1109                                 {
1110                                 dest[(*dest_len)++] = rr->data[rr->off++];
1111                                 rr->length--;
1112                                 }
1113
1114                         if (*dest_len < dest_maxlen)
1115                                 goto start; /* fragment was too small */
1116                         }
1117                 }
1118
1119         /* s->s3->handshake_fragment_len == 4  iff  rr->type == SSL3_RT_HANDSHAKE;
1120          * s->s3->alert_fragment_len == 2      iff  rr->type == SSL3_RT_ALERT.
1121          * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
1122
1123         /* If we are a client, check for an incoming 'Hello Request': */
1124         if ((!s->server) &&
1125                 (s->s3->handshake_fragment_len >= 4) &&
1126                 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1127                 (s->session != NULL) && (s->session->cipher != NULL))
1128                 {
1129                 s->s3->handshake_fragment_len = 0;
1130
1131                 if ((s->s3->handshake_fragment[1] != 0) ||
1132                         (s->s3->handshake_fragment[2] != 0) ||
1133                         (s->s3->handshake_fragment[3] != 0))
1134                         {
1135                         al=SSL_AD_DECODE_ERROR;
1136                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1137                         goto f_err;
1138                         }
1139
1140                 if (s->msg_callback)
1141                         s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
1142
1143                 if (SSL_is_init_finished(s) &&
1144                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1145                         !s->s3->renegotiate)
1146                         {
1147                         ssl3_renegotiate(s);
1148                         if (ssl3_renegotiate_check(s))
1149                                 {
1150                                 i=s->handshake_func(s);
1151                                 if (i < 0) return(i);
1152                                 if (i == 0)
1153                                         {
1154                                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1155                                         return(-1);
1156                                         }
1157
1158                                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1159                                         {
1160                                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1161                                                 {
1162                                                 BIO *bio;
1163                                                 /* In the case where we try to read application data,
1164                                                  * but we trigger an SSL handshake, we return -1 with
1165                                                  * the retry option set.  Otherwise renegotiation may
1166                                                  * cause nasty problems in the blocking world */
1167                                                 s->rwstate=SSL_READING;
1168                                                 bio=SSL_get_rbio(s);
1169                                                 BIO_clear_retry_flags(bio);
1170                                                 BIO_set_retry_read(bio);
1171                                                 return(-1);
1172                                                 }
1173                                         }
1174                                 }
1175                         }
1176                 /* we either finished a handshake or ignored the request,
1177                  * now try again to obtain the (application) data we were asked for */
1178                 goto start;
1179                 }
1180         /* If we are a server and get a client hello when renegotiation isn't
1181          * allowed send back a no renegotiation alert and carry on.
1182          * WARNING: experimental code, needs reviewing (steve)
1183          */
1184         if (s->server &&
1185                 SSL_is_init_finished(s) &&
1186                 !s->s3->send_connection_binding &&
1187                 (s->version > SSL3_VERSION) &&
1188                 (s->s3->handshake_fragment_len >= 4) &&
1189                 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1190                 (s->session != NULL) && (s->session->cipher != NULL) &&
1191                 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1192                 
1193                 {
1194                 /*s->s3->handshake_fragment_len = 0;*/
1195                 rr->length = 0;
1196                 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1197                 goto start;
1198                 }
1199         if (s->s3->alert_fragment_len >= 2)
1200                 {
1201                 int alert_level = s->s3->alert_fragment[0];
1202                 int alert_descr = s->s3->alert_fragment[1];
1203
1204                 s->s3->alert_fragment_len = 0;
1205
1206                 if (s->msg_callback)
1207                         s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1208
1209                 if (s->info_callback != NULL)
1210                         cb=s->info_callback;
1211                 else if (s->ctx->info_callback != NULL)
1212                         cb=s->ctx->info_callback;
1213
1214                 if (cb != NULL)
1215                         {
1216                         j = (alert_level << 8) | alert_descr;
1217                         cb(s, SSL_CB_READ_ALERT, j);
1218                         }
1219
1220                 if (alert_level == 1) /* warning */
1221                         {
1222                         s->s3->warn_alert = alert_descr;
1223                         if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1224                                 {
1225                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1226                                 return(0);
1227                                 }
1228                         /* This is a warning but we receive it if we requested
1229                          * renegotiation and the peer denied it. Terminate with
1230                          * a fatal alert because if application tried to
1231                          * renegotiatie it presumably had a good reason and
1232                          * expects it to succeed.
1233                          *
1234                          * In future we might have a renegotiation where we
1235                          * don't care if the peer refused it where we carry on.
1236                          */
1237                         else if (alert_descr == SSL_AD_NO_RENEGOTIATION)
1238                                 {
1239                                 al = SSL_AD_HANDSHAKE_FAILURE;
1240                                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION);
1241                                 goto f_err;
1242                                 }
1243 #ifdef SSL_AD_MISSING_SRP_USERNAME
1244                         else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME)
1245                                 return(0);
1246 #endif
1247                         }
1248                 else if (alert_level == 2) /* fatal */
1249                         {
1250                         char tmp[16];
1251
1252                         s->rwstate=SSL_NOTHING;
1253                         s->s3->fatal_alert = alert_descr;
1254                         SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1255                         BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1256                         ERR_add_error_data(2,"SSL alert number ",tmp);
1257                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1258                         SSL_CTX_remove_session(s->ctx,s->session);
1259                         return(0);
1260                         }
1261                 else
1262                         {
1263                         al=SSL_AD_ILLEGAL_PARAMETER;
1264                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1265                         goto f_err;
1266                         }
1267
1268                 goto start;
1269                 }
1270
1271         if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1272                 {
1273                 s->rwstate=SSL_NOTHING;
1274                 rr->length=0;
1275                 return(0);
1276                 }
1277
1278         if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1279                 {
1280                 /* 'Change Cipher Spec' is just a single byte, so we know
1281                  * exactly what the record payload has to look like */
1282                 if (    (rr->length != 1) || (rr->off != 0) ||
1283                         (rr->data[0] != SSL3_MT_CCS))
1284                         {
1285                         al=SSL_AD_ILLEGAL_PARAMETER;
1286                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1287                         goto f_err;
1288                         }
1289
1290                 /* Check we have a cipher to change to */
1291                 if (s->s3->tmp.new_cipher == NULL)
1292                         {
1293                         al=SSL_AD_UNEXPECTED_MESSAGE;
1294                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1295                         goto f_err;
1296                         }
1297
1298                 rr->length=0;
1299
1300                 if (s->msg_callback)
1301                         s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1302
1303                 s->s3->change_cipher_spec=1;
1304                 if (!ssl3_do_change_cipher_spec(s))
1305                         goto err;
1306                 else
1307                         goto start;
1308                 }
1309
1310         /* Unexpected handshake message (Client Hello, or protocol violation) */
1311         if ((s->s3->handshake_fragment_len >= 4) &&     !s->in_handshake)
1312                 {
1313                 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1314                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1315                         {
1316 #if 0 /* worked only because C operator preferences are not as expected (and
1317        * because this is not really needed for clients except for detecting
1318        * protocol violations): */
1319                         s->state=SSL_ST_BEFORE|(s->server)
1320                                 ?SSL_ST_ACCEPT
1321                                 :SSL_ST_CONNECT;
1322 #else
1323                         s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1324 #endif
1325                         s->renegotiate=1;
1326                         s->new_session=1;
1327                         }
1328                 i=s->handshake_func(s);
1329                 if (i < 0) return(i);
1330                 if (i == 0)
1331                         {
1332                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1333                         return(-1);
1334                         }
1335
1336                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1337                         {
1338                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1339                                 {
1340                                 BIO *bio;
1341                                 /* In the case where we try to read application data,
1342                                  * but we trigger an SSL handshake, we return -1 with
1343                                  * the retry option set.  Otherwise renegotiation may
1344                                  * cause nasty problems in the blocking world */
1345                                 s->rwstate=SSL_READING;
1346                                 bio=SSL_get_rbio(s);
1347                                 BIO_clear_retry_flags(bio);
1348                                 BIO_set_retry_read(bio);
1349                                 return(-1);
1350                                 }
1351                         }
1352                 goto start;
1353                 }
1354
1355         switch (rr->type)
1356                 {
1357         default:
1358 #ifndef OPENSSL_NO_TLS
1359                 /* TLS up to v1.1 just ignores unknown message types:
1360                  * TLS v1.2 give an unexpected message alert.
1361                  */
1362                 if (s->version >= TLS1_VERSION && s->version <= TLS1_1_VERSION)
1363                         {
1364                         rr->length = 0;
1365                         goto start;
1366                         }
1367 #endif
1368                 al=SSL_AD_UNEXPECTED_MESSAGE;
1369                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1370                 goto f_err;
1371         case SSL3_RT_CHANGE_CIPHER_SPEC:
1372         case SSL3_RT_ALERT:
1373         case SSL3_RT_HANDSHAKE:
1374                 /* we already handled all of these, with the possible exception
1375                  * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1376                  * should not happen when type != rr->type */
1377                 al=SSL_AD_UNEXPECTED_MESSAGE;
1378                 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1379                 goto f_err;
1380         case SSL3_RT_APPLICATION_DATA:
1381                 /* At this point, we were expecting handshake data,
1382                  * but have application data.  If the library was
1383                  * running inside ssl3_read() (i.e. in_read_app_data
1384                  * is set) and it makes sense to read application data
1385                  * at this point (session renegotiation not yet started),
1386                  * we will indulge it.
1387                  */
1388                 if (s->s3->in_read_app_data &&
1389                         (s->s3->total_renegotiations != 0) &&
1390                         ((
1391                                 (s->state & SSL_ST_CONNECT) &&
1392                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1393                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1394                                 ) || (
1395                                         (s->state & SSL_ST_ACCEPT) &&
1396                                         (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1397                                         (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1398                                         )
1399                                 ))
1400                         {
1401                         s->s3->in_read_app_data=2;
1402                         return(-1);
1403                         }
1404                 else
1405                         {
1406                         al=SSL_AD_UNEXPECTED_MESSAGE;
1407                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1408                         goto f_err;
1409                         }
1410                 }
1411         /* not reached */
1412
1413 f_err:
1414         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1415 err:
1416         return(-1);
1417         }
1418
1419 int ssl3_do_change_cipher_spec(SSL *s)
1420         {
1421         int i;
1422         const char *sender;
1423         int slen;
1424
1425         if (s->state & SSL_ST_ACCEPT)
1426                 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1427         else
1428                 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1429
1430         if (s->s3->tmp.key_block == NULL)
1431                 {
1432                 if (s->session == NULL) 
1433                         {
1434                         /* might happen if dtls1_read_bytes() calls this */
1435                         SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY);
1436                         return (0);
1437                         }
1438
1439                 s->session->cipher=s->s3->tmp.new_cipher;
1440                 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1441                 }
1442
1443         if (!s->method->ssl3_enc->change_cipher_state(s,i))
1444                 return(0);
1445
1446         /* we have to record the message digest at
1447          * this point so we can get it before we read
1448          * the finished message */
1449         if (s->state & SSL_ST_CONNECT)
1450                 {
1451                 sender=s->method->ssl3_enc->server_finished_label;
1452                 slen=s->method->ssl3_enc->server_finished_label_len;
1453                 }
1454         else
1455                 {
1456                 sender=s->method->ssl3_enc->client_finished_label;
1457                 slen=s->method->ssl3_enc->client_finished_label_len;
1458                 }
1459
1460         s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1461                 sender,slen,s->s3->tmp.peer_finish_md);
1462
1463         return(1);
1464         }
1465
1466 int ssl3_send_alert(SSL *s, int level, int desc)
1467         {
1468         /* Map tls/ssl alert value to correct one */
1469         desc=s->method->ssl3_enc->alert_value(desc);
1470         if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1471                 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1472         if (desc < 0) return -1;
1473         /* If a fatal one, remove from cache */
1474         if ((level == 2) && (s->session != NULL))
1475                 SSL_CTX_remove_session(s->ctx,s->session);
1476
1477         s->s3->alert_dispatch=1;
1478         s->s3->send_alert[0]=level;
1479         s->s3->send_alert[1]=desc;
1480         if (s->s3->wbuf.left == 0) /* data still being written out? */
1481                 return s->method->ssl_dispatch_alert(s);
1482         /* else data is still being written out, we will get written
1483          * some time in the future */
1484         return -1;
1485         }
1486
1487 int ssl3_dispatch_alert(SSL *s)
1488         {
1489         int i,j;
1490         void (*cb)(const SSL *ssl,int type,int val)=NULL;
1491
1492         s->s3->alert_dispatch=0;
1493         i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1494         if (i <= 0)
1495                 {
1496                 s->s3->alert_dispatch=1;
1497                 }
1498         else
1499                 {
1500                 /* Alert sent to BIO.  If it is important, flush it now.
1501                  * If the message does not get sent due to non-blocking IO,
1502                  * we will not worry too much. */
1503                 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1504                         (void)BIO_flush(s->wbio);
1505
1506                 if (s->msg_callback)
1507                         s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1508
1509                 if (s->info_callback != NULL)
1510                         cb=s->info_callback;
1511                 else if (s->ctx->info_callback != NULL)
1512                         cb=s->ctx->info_callback;
1513
1514                 if (cb != NULL)
1515                         {
1516                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1517                         cb(s,SSL_CB_WRITE_ALERT,j);
1518                         }
1519                 }
1520         return(i);
1521         }