ssl/*: remove SSL3_RECORD->orig_len to restore binary compatibility.
[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         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                 if (s->msg_callback)
322                         s->msg_callback(0, 0, SSL3_RT_HEADER, p, 5, s, s->msg_callback_arg);
323
324                 /* Pull apart the header into the SSL3_RECORD */
325                 rr->type= *(p++);
326                 ssl_major= *(p++);
327                 ssl_minor= *(p++);
328                 version=(ssl_major<<8)|ssl_minor;
329                 n2s(p,rr->length);
330 #if 0
331 fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length);
332 #endif
333
334                 /* Lets check version */
335                 if (!s->first_packet)
336                         {
337                         if (version != s->version)
338                                 {
339                                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
340                                 if ((s->version & 0xFF00) == (version & 0xFF00))
341                                         /* Send back error using their minor version number :-) */
342                                         s->version = (unsigned short)version;
343                                 al=SSL_AD_PROTOCOL_VERSION;
344                                 goto f_err;
345                                 }
346                         }
347
348                 if ((version>>8) != SSL3_VERSION_MAJOR)
349                         {
350                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
351                         goto err;
352                         }
353
354                 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH)
355                         {
356                         al=SSL_AD_RECORD_OVERFLOW;
357                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
358                         goto f_err;
359                         }
360
361                 /* now s->rstate == SSL_ST_READ_BODY */
362                 }
363
364         /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
365
366         if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
367                 {
368                 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
369                 i=rr->length;
370                 n=ssl3_read_n(s,i,i,1);
371                 if (n <= 0) return(n); /* error or non-blocking io */
372                 /* now n == rr->length,
373                  * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
374                 }
375
376         s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
377
378         /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
379          * and we have that many bytes in s->packet
380          */
381         rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
382
383         /* ok, we can now read from 's->packet' data into 'rr'
384          * rr->input points at rr->length bytes, which
385          * need to be copied into rr->data by either
386          * the decryption or by the decompression
387          * When the data is 'copied' into the rr->data buffer,
388          * rr->input will be pointed at the new buffer */ 
389
390         /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
391          * rr->length bytes of encrypted compressed stuff. */
392
393         /* check is not needed I believe */
394         if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
395                 {
396                 al=SSL_AD_RECORD_OVERFLOW;
397                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
398                 goto f_err;
399                 }
400
401         /* decrypt in place in 'rr->input' */
402         rr->data=rr->input;
403         orig_len=rr->length;
404
405         enc_err = s->method->ssl3_enc->enc(s,0);
406         /* enc_err is:
407          *    0: (in non-constant time) if the record is publically invalid.
408          *    1: if the padding is valid
409          *    -1: if the padding is invalid */
410         if (enc_err == 0)
411                 {
412                 al=SSL_AD_DECRYPTION_FAILED;
413                 SSLerr(SSL_F_TLS1_ENC,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
414                 goto f_err;
415                 }
416
417 #ifdef TLS_DEBUG
418 printf("dec %d\n",rr->length);
419 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
420 printf("\n");
421 #endif
422
423         /* r->length is now the compressed data plus mac */
424         if ((sess != NULL) &&
425             (s->enc_read_ctx != NULL) &&
426             (EVP_MD_CTX_md(s->read_hash) != NULL))
427                 {
428                 /* s->read_hash != NULL => mac_size != -1 */
429                 unsigned char *mac = NULL;
430                 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
431                 mac_size=EVP_MD_CTX_size(s->read_hash);
432                 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
433
434                 /* orig_len is the length of the record before any padding was
435                  * removed. This is public information, as is the MAC in use,
436                  * therefore we can safely process the record in a different
437                  * amount of time if it's too short to possibly contain a MAC.
438                  */
439                 if (orig_len < mac_size ||
440                     /* CBC records must have a padding length byte too. */
441                     (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
442                      orig_len < mac_size+1))
443                         {
444                         al=SSL_AD_DECODE_ERROR;
445                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
446                         goto f_err;
447                         }
448
449                 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE)
450                         {
451                         /* We update the length so that the TLS header bytes
452                          * can be constructed correctly but we need to extract
453                          * the MAC in constant time from within the record,
454                          * without leaking the contents of the padding bytes.
455                          * */
456                         mac = mac_tmp;
457                         ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
458                         rr->length -= mac_size;
459                         }
460                 else
461                         {
462                         /* In this case there's no padding, so |orig_len|
463                          * equals |rec->length| and we checked that there's
464                          * enough bytes for |mac_size| above. */
465                         rr->length -= mac_size;
466                         mac = &rr->data[rr->length];
467                         }
468
469                 i=s->method->ssl3_enc->mac(s,md,0 /* not send */);
470                 if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
471                         enc_err = -1;
472                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
473                         enc_err = -1;
474                 }
475
476         if (enc_err < 0)
477                 {
478                 /* A separate 'decryption_failed' alert was introduced with TLS 1.0,
479                  * SSL 3.0 only has 'bad_record_mac'.  But unless a decryption
480                  * failure is directly visible from the ciphertext anyway,
481                  * we should not reveal which kind of error occured -- this
482                  * might become visible to an attacker (e.g. via a logfile) */
483                 al=SSL_AD_BAD_RECORD_MAC;
484                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
485                 goto f_err;
486                 }
487
488         /* r->length is now just compressed */
489         if (s->expand != NULL)
490                 {
491                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
492                         {
493                         al=SSL_AD_RECORD_OVERFLOW;
494                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
495                         goto f_err;
496                         }
497                 if (!ssl3_do_uncompress(s))
498                         {
499                         al=SSL_AD_DECOMPRESSION_FAILURE;
500                         SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
501                         goto f_err;
502                         }
503                 }
504
505         if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
506                 {
507                 al=SSL_AD_RECORD_OVERFLOW;
508                 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
509                 goto f_err;
510                 }
511
512         rr->off=0;
513         /* So at this point the following is true
514          * ssl->s3->rrec.type   is the type of record
515          * ssl->s3->rrec.length == number of bytes in record
516          * ssl->s3->rrec.off    == offset to first valid byte
517          * ssl->s3->rrec.data   == where to take bytes from, increment
518          *                         after use :-).
519          */
520
521         /* we have pulled in a full packet so zero things */
522         s->packet_length=0;
523
524         /* just read a 0 length packet */
525         if (rr->length == 0) goto again;
526
527 #if 0
528 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length);
529 #endif
530
531         return(1);
532
533 f_err:
534         ssl3_send_alert(s,SSL3_AL_FATAL,al);
535 err:
536         return(ret);
537         }
538
539 int ssl3_do_uncompress(SSL *ssl)
540         {
541 #ifndef OPENSSL_NO_COMP
542         int i;
543         SSL3_RECORD *rr;
544
545         rr= &(ssl->s3->rrec);
546         i=COMP_expand_block(ssl->expand,rr->comp,
547                 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
548         if (i < 0)
549                 return(0);
550         else
551                 rr->length=i;
552         rr->data=rr->comp;
553 #endif
554         return(1);
555         }
556
557 int ssl3_do_compress(SSL *ssl)
558         {
559 #ifndef OPENSSL_NO_COMP
560         int i;
561         SSL3_RECORD *wr;
562
563         wr= &(ssl->s3->wrec);
564         i=COMP_compress_block(ssl->compress,wr->data,
565                 SSL3_RT_MAX_COMPRESSED_LENGTH,
566                 wr->input,(int)wr->length);
567         if (i < 0)
568                 return(0);
569         else
570                 wr->length=i;
571
572         wr->input=wr->data;
573 #endif
574         return(1);
575         }
576
577 /* Call this to write data in records of type 'type'
578  * It will return <= 0 if not all data has been sent or non-blocking IO.
579  */
580 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
581         {
582         const unsigned char *buf=buf_;
583         unsigned int tot,n,nw;
584         int i;
585
586         s->rwstate=SSL_NOTHING;
587         tot=s->s3->wnum;
588         s->s3->wnum=0;
589
590         if (SSL_in_init(s) && !s->in_handshake)
591                 {
592                 i=s->handshake_func(s);
593                 if (i < 0) return(i);
594                 if (i == 0)
595                         {
596                         SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
597                         return -1;
598                         }
599                 }
600
601         n=(len-tot);
602         for (;;)
603                 {
604                 if (n > s->max_send_fragment)
605                         nw=s->max_send_fragment;
606                 else
607                         nw=n;
608
609                 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
610                 if (i <= 0)
611                         {
612                         s->s3->wnum=tot;
613                         return i;
614                         }
615
616                 if ((i == (int)n) ||
617                         (type == SSL3_RT_APPLICATION_DATA &&
618                          (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
619                         {
620                         /* next chunk of data should get another prepended empty fragment
621                          * in ciphersuites with known-IV weakness: */
622                         s->s3->empty_fragment_done = 0;
623                         
624                         return tot+i;
625                         }
626
627                 n-=i;
628                 tot+=i;
629                 }
630         }
631
632 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
633                          unsigned int len, int create_empty_fragment)
634         {
635         unsigned char *p,*plen;
636         int i,mac_size,clear=0;
637         int prefix_len=0;
638         int eivlen;
639         long align=0;
640         SSL3_RECORD *wr;
641         SSL3_BUFFER *wb=&(s->s3->wbuf);
642         SSL_SESSION *sess;
643
644         if (wb->buf == NULL)
645                 if (!ssl3_setup_write_buffer(s))
646                         return -1;
647
648         /* first check if there is a SSL3_BUFFER still being written
649          * out.  This will happen with non blocking IO */
650         if (wb->left != 0)
651                 return(ssl3_write_pending(s,type,buf,len));
652
653         /* If we have an alert to send, lets send it */
654         if (s->s3->alert_dispatch)
655                 {
656                 i=s->method->ssl_dispatch_alert(s);
657                 if (i <= 0)
658                         return(i);
659                 /* if it went, fall through and send more stuff */
660                 }
661
662         if (len == 0 && !create_empty_fragment)
663                 return 0;
664
665         wr= &(s->s3->wrec);
666         sess=s->session;
667
668         if (    (sess == NULL) ||
669                 (s->enc_write_ctx == NULL) ||
670                 (EVP_MD_CTX_md(s->write_hash) == NULL))
671                 {
672 #if 1
673                 clear=s->enc_write_ctx?0:1;     /* must be AEAD cipher */
674 #else
675                 clear=1;
676 #endif
677                 mac_size=0;
678                 }
679         else
680                 {
681                 mac_size=EVP_MD_CTX_size(s->write_hash);
682                 if (mac_size < 0)
683                         goto err;
684                 }
685
686         /* 'create_empty_fragment' is true only when this function calls itself */
687         if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
688                 {
689                 /* countermeasure against known-IV weakness in CBC ciphersuites
690                  * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
691
692                 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
693                         {
694                         /* recursive function call with 'create_empty_fragment' set;
695                          * this prepares and buffers the data for an empty fragment
696                          * (these 'prefix_len' bytes are sent out later
697                          * together with the actual payload) */
698                         prefix_len = do_ssl3_write(s, type, buf, 0, 1);
699                         if (prefix_len <= 0)
700                                 goto err;
701
702                         if (prefix_len >
703                 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD))
704                                 {
705                                 /* insufficient space */
706                                 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
707                                 goto err;
708                                 }
709                         }
710                 
711                 s->s3->empty_fragment_done = 1;
712                 }
713
714         if (create_empty_fragment)
715                 {
716 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
717                 /* extra fragment would be couple of cipher blocks,
718                  * which would be multiple of SSL3_ALIGN_PAYLOAD, so
719                  * if we want to align the real payload, then we can
720                  * just pretent we simply have two headers. */
721                 align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH;
722                 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
723 #endif
724                 p = wb->buf + align;
725                 wb->offset  = align;
726                 }
727         else if (prefix_len)
728                 {
729                 p = wb->buf + wb->offset + prefix_len;
730                 }
731         else
732                 {
733 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
734                 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH;
735                 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
736 #endif
737                 p = wb->buf + align;
738                 wb->offset  = align;
739                 }
740
741         /* write the header */
742
743         *(p++)=type&0xff;
744         wr->type=type;
745
746         *(p++)=(s->version>>8);
747         /* Some servers hang if iniatial client hello is larger than 256
748          * bytes and record version number > TLS 1.0
749          */
750         if (s->state == SSL3_ST_CW_CLNT_HELLO_B
751                                 && !s->renegotiate
752                                 && TLS1_get_version(s) > TLS1_VERSION)
753                 *(p++) = 0x1;
754         else
755                 *(p++)=s->version&0xff;
756
757         /* field where we are to write out packet length */
758         plen=p; 
759         p+=2;
760         /* Explicit IV length, block ciphers and TLS version 1.1 or later */
761         if (s->enc_write_ctx && s->version >= TLS1_1_VERSION)
762                 {
763                 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
764                 if (mode == EVP_CIPH_CBC_MODE)
765                         {
766                         eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
767                         if (eivlen <= 1)
768                                 eivlen = 0;
769                         }
770                 /* Need explicit part of IV for GCM mode */
771                 else if (mode == EVP_CIPH_GCM_MODE)
772                         eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
773                 else
774                         eivlen = 0;
775                 }
776         else 
777                 eivlen = 0;
778
779         /* lets setup the record stuff. */
780         wr->data=p + eivlen;
781         wr->length=(int)len;
782         wr->input=(unsigned char *)buf;
783
784         /* we now 'read' from wr->input, wr->length bytes into
785          * wr->data */
786
787         /* first we compress */
788         if (s->compress != NULL)
789                 {
790                 if (!ssl3_do_compress(s))
791                         {
792                         SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
793                         goto err;
794                         }
795                 }
796         else
797                 {
798                 memcpy(wr->data,wr->input,wr->length);
799                 wr->input=wr->data;
800                 }
801
802         /* we should still have the output to wr->data and the input
803          * from wr->input.  Length should be wr->length.
804          * wr->data still points in the wb->buf */
805
806         if (mac_size != 0)
807                 {
808                 if (s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0)
809                         goto err;
810                 wr->length+=mac_size;
811                 }
812
813         wr->input=p;
814         wr->data=p;
815
816         if (eivlen)
817                 {
818         /*      if (RAND_pseudo_bytes(p, eivlen) <= 0)
819                         goto err; */
820                 wr->length += eivlen;
821                 }
822
823         /* ssl3_enc can only have an error on read */
824         s->method->ssl3_enc->enc(s,1);
825
826         /* record length after mac and block padding */
827         s2n(wr->length,plen);
828
829         if (s->msg_callback)
830                 s->msg_callback(1, 0, SSL3_RT_HEADER, plen - 5, 5, s, s->msg_callback_arg);
831
832         /* we should now have
833          * wr->data pointing to the encrypted data, which is
834          * wr->length long */
835         wr->type=type; /* not needed but helps for debugging */
836         wr->length+=SSL3_RT_HEADER_LENGTH;
837
838         if (create_empty_fragment)
839                 {
840                 /* we are in a recursive call;
841                  * just return the length, don't write out anything here
842                  */
843                 return wr->length;
844                 }
845
846         /* now let's set up wb */
847         wb->left = prefix_len + wr->length;
848
849         /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
850         s->s3->wpend_tot=len;
851         s->s3->wpend_buf=buf;
852         s->s3->wpend_type=type;
853         s->s3->wpend_ret=len;
854
855         /* we now just need to write the buffer */
856         return ssl3_write_pending(s,type,buf,len);
857 err:
858         return -1;
859         }
860
861 /* if s->s3->wbuf.left != 0, we need to call this */
862 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
863         unsigned int len)
864         {
865         int i;
866         SSL3_BUFFER *wb=&(s->s3->wbuf);
867
868 /* XXXX */
869         if ((s->s3->wpend_tot > (int)len)
870                 || ((s->s3->wpend_buf != buf) &&
871                         !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
872                 || (s->s3->wpend_type != type))
873                 {
874                 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
875                 return(-1);
876                 }
877
878         for (;;)
879                 {
880                 clear_sys_error();
881                 if (s->wbio != NULL)
882                         {
883                         s->rwstate=SSL_WRITING;
884                         i=BIO_write(s->wbio,
885                                 (char *)&(wb->buf[wb->offset]),
886                                 (unsigned int)wb->left);
887                         }
888                 else
889                         {
890                         SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
891                         i= -1;
892                         }
893                 if (i == wb->left)
894                         {
895                         wb->left=0;
896                         wb->offset+=i;
897                         if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
898                             SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
899                                 ssl3_release_write_buffer(s);
900                         s->rwstate=SSL_NOTHING;
901                         return(s->s3->wpend_ret);
902                         }
903                 else if (i <= 0) {
904                         if (s->version == DTLS1_VERSION ||
905                             s->version == DTLS1_BAD_VER) {
906                                 /* For DTLS, just drop it. That's kind of the whole
907                                    point in using a datagram service */
908                                 wb->left = 0;
909                         }
910                         return(i);
911                 }
912                 wb->offset+=i;
913                 wb->left-=i;
914                 }
915         }
916
917 /* Return up to 'len' payload bytes received in 'type' records.
918  * 'type' is one of the following:
919  *
920  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
921  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
922  *   -  0 (during a shutdown, no data has to be returned)
923  *
924  * If we don't have stored data to work from, read a SSL/TLS record first
925  * (possibly multiple records if we still don't have anything to return).
926  *
927  * This function must handle any surprises the peer may have for us, such as
928  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
929  * a surprise, but handled as if it were), or renegotiation requests.
930  * Also if record payloads contain fragments too small to process, we store
931  * them until there is enough for the respective protocol (the record protocol
932  * may use arbitrary fragmentation and even interleaving):
933  *     Change cipher spec protocol
934  *             just 1 byte needed, no need for keeping anything stored
935  *     Alert protocol
936  *             2 bytes needed (AlertLevel, AlertDescription)
937  *     Handshake protocol
938  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
939  *             to detect unexpected Client Hello and Hello Request messages
940  *             here, anything else is handled by higher layers
941  *     Application data protocol
942  *             none of our business
943  */
944 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
945         {
946         int al,i,j,ret;
947         unsigned int n;
948         SSL3_RECORD *rr;
949         void (*cb)(const SSL *ssl,int type2,int val)=NULL;
950
951         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
952                 if (!ssl3_setup_read_buffer(s))
953                         return(-1);
954
955         if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) ||
956             (peek && (type != SSL3_RT_APPLICATION_DATA)))
957                 {
958                 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
959                 return -1;
960                 }
961
962         if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
963                 /* (partially) satisfy request from storage */
964                 {
965                 unsigned char *src = s->s3->handshake_fragment;
966                 unsigned char *dst = buf;
967                 unsigned int k;
968
969                 /* peek == 0 */
970                 n = 0;
971                 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
972                         {
973                         *dst++ = *src++;
974                         len--; s->s3->handshake_fragment_len--;
975                         n++;
976                         }
977                 /* move any remaining fragment bytes: */
978                 for (k = 0; k < s->s3->handshake_fragment_len; k++)
979                         s->s3->handshake_fragment[k] = *src++;
980                 return n;
981         }
982
983         /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
984
985         if (!s->in_handshake && SSL_in_init(s))
986                 {
987                 /* type == SSL3_RT_APPLICATION_DATA */
988                 i=s->handshake_func(s);
989                 if (i < 0) return(i);
990                 if (i == 0)
991                         {
992                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
993                         return(-1);
994                         }
995                 }
996 start:
997         s->rwstate=SSL_NOTHING;
998
999         /* s->s3->rrec.type         - is the type of record
1000          * s->s3->rrec.data,    - data
1001          * s->s3->rrec.off,     - offset into 'data' for next read
1002          * s->s3->rrec.length,  - number of bytes. */
1003         rr = &(s->s3->rrec);
1004
1005         /* get new packet if necessary */
1006         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
1007                 {
1008                 ret=ssl3_get_record(s);
1009                 if (ret <= 0) return(ret);
1010                 }
1011
1012         /* we now have a packet which can be read and processed */
1013
1014         if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
1015                                        * reset by ssl3_get_finished */
1016                 && (rr->type != SSL3_RT_HANDSHAKE))
1017                 {
1018                 al=SSL_AD_UNEXPECTED_MESSAGE;
1019                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
1020                 goto f_err;
1021                 }
1022
1023         /* If the other end has shut down, throw anything we read away
1024          * (even in 'peek' mode) */
1025         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
1026                 {
1027                 rr->length=0;
1028                 s->rwstate=SSL_NOTHING;
1029                 return(0);
1030                 }
1031
1032
1033         if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
1034                 {
1035                 /* make sure that we are not getting application data when we
1036                  * are doing a handshake for the first time */
1037                 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
1038                         (s->enc_read_ctx == NULL))
1039                         {
1040                         al=SSL_AD_UNEXPECTED_MESSAGE;
1041                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
1042                         goto f_err;
1043                         }
1044
1045                 if (len <= 0) return(len);
1046
1047                 if ((unsigned int)len > rr->length)
1048                         n = rr->length;
1049                 else
1050                         n = (unsigned int)len;
1051
1052                 memcpy(buf,&(rr->data[rr->off]),n);
1053                 if (!peek)
1054                         {
1055                         rr->length-=n;
1056                         rr->off+=n;
1057                         if (rr->length == 0)
1058                                 {
1059                                 s->rstate=SSL_ST_READ_HEADER;
1060                                 rr->off=0;
1061                                 if (s->mode & SSL_MODE_RELEASE_BUFFERS)
1062                                         ssl3_release_read_buffer(s);
1063                                 }
1064                         }
1065                 return(n);
1066                 }
1067
1068
1069         /* If we get here, then type != rr->type; if we have a handshake
1070          * message, then it was unexpected (Hello Request or Client Hello). */
1071
1072         /* In case of record types for which we have 'fragment' storage,
1073          * fill that so that we can process the data at a fixed place.
1074          */
1075                 {
1076                 unsigned int dest_maxlen = 0;
1077                 unsigned char *dest = NULL;
1078                 unsigned int *dest_len = NULL;
1079
1080                 if (rr->type == SSL3_RT_HANDSHAKE)
1081                         {
1082                         dest_maxlen = sizeof s->s3->handshake_fragment;
1083                         dest = s->s3->handshake_fragment;
1084                         dest_len = &s->s3->handshake_fragment_len;
1085                         }
1086                 else if (rr->type == SSL3_RT_ALERT)
1087                         {
1088                         dest_maxlen = sizeof s->s3->alert_fragment;
1089                         dest = s->s3->alert_fragment;
1090                         dest_len = &s->s3->alert_fragment_len;
1091                         }
1092 #ifndef OPENSSL_NO_HEARTBEATS
1093                 else if (rr->type == TLS1_RT_HEARTBEAT)
1094                         {
1095                         tls1_process_heartbeat(s);
1096
1097                         /* Exit and notify application to read again */
1098                         rr->length = 0;
1099                         s->rwstate=SSL_READING;
1100                         BIO_clear_retry_flags(SSL_get_rbio(s));
1101                         BIO_set_retry_read(SSL_get_rbio(s));
1102                         return(-1);
1103                         }
1104 #endif
1105
1106                 if (dest_maxlen > 0)
1107                         {
1108                         n = dest_maxlen - *dest_len; /* available space in 'dest' */
1109                         if (rr->length < n)
1110                                 n = rr->length; /* available bytes */
1111
1112                         /* now move 'n' bytes: */
1113                         while (n-- > 0)
1114                                 {
1115                                 dest[(*dest_len)++] = rr->data[rr->off++];
1116                                 rr->length--;
1117                                 }
1118
1119                         if (*dest_len < dest_maxlen)
1120                                 goto start; /* fragment was too small */
1121                         }
1122                 }
1123
1124         /* s->s3->handshake_fragment_len == 4  iff  rr->type == SSL3_RT_HANDSHAKE;
1125          * s->s3->alert_fragment_len == 2      iff  rr->type == SSL3_RT_ALERT.
1126          * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
1127
1128         /* If we are a client, check for an incoming 'Hello Request': */
1129         if ((!s->server) &&
1130                 (s->s3->handshake_fragment_len >= 4) &&
1131                 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1132                 (s->session != NULL) && (s->session->cipher != NULL))
1133                 {
1134                 s->s3->handshake_fragment_len = 0;
1135
1136                 if ((s->s3->handshake_fragment[1] != 0) ||
1137                         (s->s3->handshake_fragment[2] != 0) ||
1138                         (s->s3->handshake_fragment[3] != 0))
1139                         {
1140                         al=SSL_AD_DECODE_ERROR;
1141                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1142                         goto f_err;
1143                         }
1144
1145                 if (s->msg_callback)
1146                         s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
1147
1148                 if (SSL_is_init_finished(s) &&
1149                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1150                         !s->s3->renegotiate)
1151                         {
1152                         ssl3_renegotiate(s);
1153                         if (ssl3_renegotiate_check(s))
1154                                 {
1155                                 i=s->handshake_func(s);
1156                                 if (i < 0) return(i);
1157                                 if (i == 0)
1158                                         {
1159                                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1160                                         return(-1);
1161                                         }
1162
1163                                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1164                                         {
1165                                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1166                                                 {
1167                                                 BIO *bio;
1168                                                 /* In the case where we try to read application data,
1169                                                  * but we trigger an SSL handshake, we return -1 with
1170                                                  * the retry option set.  Otherwise renegotiation may
1171                                                  * cause nasty problems in the blocking world */
1172                                                 s->rwstate=SSL_READING;
1173                                                 bio=SSL_get_rbio(s);
1174                                                 BIO_clear_retry_flags(bio);
1175                                                 BIO_set_retry_read(bio);
1176                                                 return(-1);
1177                                                 }
1178                                         }
1179                                 }
1180                         }
1181                 /* we either finished a handshake or ignored the request,
1182                  * now try again to obtain the (application) data we were asked for */
1183                 goto start;
1184                 }
1185         /* If we are a server and get a client hello when renegotiation isn't
1186          * allowed send back a no renegotiation alert and carry on.
1187          * WARNING: experimental code, needs reviewing (steve)
1188          */
1189         if (s->server &&
1190                 SSL_is_init_finished(s) &&
1191                 !s->s3->send_connection_binding &&
1192                 (s->version > SSL3_VERSION) &&
1193                 (s->s3->handshake_fragment_len >= 4) &&
1194                 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1195                 (s->session != NULL) && (s->session->cipher != NULL) &&
1196                 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1197                 
1198                 {
1199                 /*s->s3->handshake_fragment_len = 0;*/
1200                 rr->length = 0;
1201                 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1202                 goto start;
1203                 }
1204         if (s->s3->alert_fragment_len >= 2)
1205                 {
1206                 int alert_level = s->s3->alert_fragment[0];
1207                 int alert_descr = s->s3->alert_fragment[1];
1208
1209                 s->s3->alert_fragment_len = 0;
1210
1211                 if (s->msg_callback)
1212                         s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1213
1214                 if (s->info_callback != NULL)
1215                         cb=s->info_callback;
1216                 else if (s->ctx->info_callback != NULL)
1217                         cb=s->ctx->info_callback;
1218
1219                 if (cb != NULL)
1220                         {
1221                         j = (alert_level << 8) | alert_descr;
1222                         cb(s, SSL_CB_READ_ALERT, j);
1223                         }
1224
1225                 if (alert_level == 1) /* warning */
1226                         {
1227                         s->s3->warn_alert = alert_descr;
1228                         if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1229                                 {
1230                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1231                                 return(0);
1232                                 }
1233                         /* This is a warning but we receive it if we requested
1234                          * renegotiation and the peer denied it. Terminate with
1235                          * a fatal alert because if application tried to
1236                          * renegotiatie it presumably had a good reason and
1237                          * expects it to succeed.
1238                          *
1239                          * In future we might have a renegotiation where we
1240                          * don't care if the peer refused it where we carry on.
1241                          */
1242                         else if (alert_descr == SSL_AD_NO_RENEGOTIATION)
1243                                 {
1244                                 al = SSL_AD_HANDSHAKE_FAILURE;
1245                                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION);
1246                                 goto f_err;
1247                                 }
1248 #ifdef SSL_AD_MISSING_SRP_USERNAME
1249                         else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME)
1250                                 return(0);
1251 #endif
1252                         }
1253                 else if (alert_level == 2) /* fatal */
1254                         {
1255                         char tmp[16];
1256
1257                         s->rwstate=SSL_NOTHING;
1258                         s->s3->fatal_alert = alert_descr;
1259                         SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1260                         BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1261                         ERR_add_error_data(2,"SSL alert number ",tmp);
1262                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1263                         SSL_CTX_remove_session(s->ctx,s->session);
1264                         return(0);
1265                         }
1266                 else
1267                         {
1268                         al=SSL_AD_ILLEGAL_PARAMETER;
1269                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1270                         goto f_err;
1271                         }
1272
1273                 goto start;
1274                 }
1275
1276         if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1277                 {
1278                 s->rwstate=SSL_NOTHING;
1279                 rr->length=0;
1280                 return(0);
1281                 }
1282
1283         if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1284                 {
1285                 /* 'Change Cipher Spec' is just a single byte, so we know
1286                  * exactly what the record payload has to look like */
1287                 if (    (rr->length != 1) || (rr->off != 0) ||
1288                         (rr->data[0] != SSL3_MT_CCS))
1289                         {
1290                         al=SSL_AD_ILLEGAL_PARAMETER;
1291                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1292                         goto f_err;
1293                         }
1294
1295                 /* Check we have a cipher to change to */
1296                 if (s->s3->tmp.new_cipher == NULL)
1297                         {
1298                         al=SSL_AD_UNEXPECTED_MESSAGE;
1299                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1300                         goto f_err;
1301                         }
1302
1303                 rr->length=0;
1304
1305                 if (s->msg_callback)
1306                         s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1307
1308                 s->s3->change_cipher_spec=1;
1309                 if (!ssl3_do_change_cipher_spec(s))
1310                         goto err;
1311                 else
1312                         goto start;
1313                 }
1314
1315         /* Unexpected handshake message (Client Hello, or protocol violation) */
1316         if ((s->s3->handshake_fragment_len >= 4) &&     !s->in_handshake)
1317                 {
1318                 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1319                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1320                         {
1321 #if 0 /* worked only because C operator preferences are not as expected (and
1322        * because this is not really needed for clients except for detecting
1323        * protocol violations): */
1324                         s->state=SSL_ST_BEFORE|(s->server)
1325                                 ?SSL_ST_ACCEPT
1326                                 :SSL_ST_CONNECT;
1327 #else
1328                         s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1329 #endif
1330                         s->renegotiate=1;
1331                         s->new_session=1;
1332                         }
1333                 i=s->handshake_func(s);
1334                 if (i < 0) return(i);
1335                 if (i == 0)
1336                         {
1337                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1338                         return(-1);
1339                         }
1340
1341                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1342                         {
1343                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1344                                 {
1345                                 BIO *bio;
1346                                 /* In the case where we try to read application data,
1347                                  * but we trigger an SSL handshake, we return -1 with
1348                                  * the retry option set.  Otherwise renegotiation may
1349                                  * cause nasty problems in the blocking world */
1350                                 s->rwstate=SSL_READING;
1351                                 bio=SSL_get_rbio(s);
1352                                 BIO_clear_retry_flags(bio);
1353                                 BIO_set_retry_read(bio);
1354                                 return(-1);
1355                                 }
1356                         }
1357                 goto start;
1358                 }
1359
1360         switch (rr->type)
1361                 {
1362         default:
1363 #ifndef OPENSSL_NO_TLS
1364                 /* TLS up to v1.1 just ignores unknown message types:
1365                  * TLS v1.2 give an unexpected message alert.
1366                  */
1367                 if (s->version >= TLS1_VERSION && s->version <= TLS1_1_VERSION)
1368                         {
1369                         rr->length = 0;
1370                         goto start;
1371                         }
1372 #endif
1373                 al=SSL_AD_UNEXPECTED_MESSAGE;
1374                 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1375                 goto f_err;
1376         case SSL3_RT_CHANGE_CIPHER_SPEC:
1377         case SSL3_RT_ALERT:
1378         case SSL3_RT_HANDSHAKE:
1379                 /* we already handled all of these, with the possible exception
1380                  * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1381                  * should not happen when type != rr->type */
1382                 al=SSL_AD_UNEXPECTED_MESSAGE;
1383                 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1384                 goto f_err;
1385         case SSL3_RT_APPLICATION_DATA:
1386                 /* At this point, we were expecting handshake data,
1387                  * but have application data.  If the library was
1388                  * running inside ssl3_read() (i.e. in_read_app_data
1389                  * is set) and it makes sense to read application data
1390                  * at this point (session renegotiation not yet started),
1391                  * we will indulge it.
1392                  */
1393                 if (s->s3->in_read_app_data &&
1394                         (s->s3->total_renegotiations != 0) &&
1395                         ((
1396                                 (s->state & SSL_ST_CONNECT) &&
1397                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1398                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1399                                 ) || (
1400                                         (s->state & SSL_ST_ACCEPT) &&
1401                                         (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1402                                         (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1403                                         )
1404                                 ))
1405                         {
1406                         s->s3->in_read_app_data=2;
1407                         return(-1);
1408                         }
1409                 else
1410                         {
1411                         al=SSL_AD_UNEXPECTED_MESSAGE;
1412                         SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1413                         goto f_err;
1414                         }
1415                 }
1416         /* not reached */
1417
1418 f_err:
1419         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1420 err:
1421         return(-1);
1422         }
1423
1424 int ssl3_do_change_cipher_spec(SSL *s)
1425         {
1426         int i;
1427         const char *sender;
1428         int slen;
1429
1430         if (s->state & SSL_ST_ACCEPT)
1431                 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1432         else
1433                 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1434
1435         if (s->s3->tmp.key_block == NULL)
1436                 {
1437                 if (s->session == NULL) 
1438                         {
1439                         /* might happen if dtls1_read_bytes() calls this */
1440                         SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY);
1441                         return (0);
1442                         }
1443
1444                 s->session->cipher=s->s3->tmp.new_cipher;
1445                 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1446                 }
1447
1448         if (!s->method->ssl3_enc->change_cipher_state(s,i))
1449                 return(0);
1450
1451         /* we have to record the message digest at
1452          * this point so we can get it before we read
1453          * the finished message */
1454         if (s->state & SSL_ST_CONNECT)
1455                 {
1456                 sender=s->method->ssl3_enc->server_finished_label;
1457                 slen=s->method->ssl3_enc->server_finished_label_len;
1458                 }
1459         else
1460                 {
1461                 sender=s->method->ssl3_enc->client_finished_label;
1462                 slen=s->method->ssl3_enc->client_finished_label_len;
1463                 }
1464
1465         s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1466                 sender,slen,s->s3->tmp.peer_finish_md);
1467
1468         return(1);
1469         }
1470
1471 int ssl3_send_alert(SSL *s, int level, int desc)
1472         {
1473         /* Map tls/ssl alert value to correct one */
1474         desc=s->method->ssl3_enc->alert_value(desc);
1475         if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1476                 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1477         if (desc < 0) return -1;
1478         /* If a fatal one, remove from cache */
1479         if ((level == 2) && (s->session != NULL))
1480                 SSL_CTX_remove_session(s->ctx,s->session);
1481
1482         s->s3->alert_dispatch=1;
1483         s->s3->send_alert[0]=level;
1484         s->s3->send_alert[1]=desc;
1485         if (s->s3->wbuf.left == 0) /* data still being written out? */
1486                 return s->method->ssl_dispatch_alert(s);
1487         /* else data is still being written out, we will get written
1488          * some time in the future */
1489         return -1;
1490         }
1491
1492 int ssl3_dispatch_alert(SSL *s)
1493         {
1494         int i,j;
1495         void (*cb)(const SSL *ssl,int type,int val)=NULL;
1496
1497         s->s3->alert_dispatch=0;
1498         i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1499         if (i <= 0)
1500                 {
1501                 s->s3->alert_dispatch=1;
1502                 }
1503         else
1504                 {
1505                 /* Alert sent to BIO.  If it is important, flush it now.
1506                  * If the message does not get sent due to non-blocking IO,
1507                  * we will not worry too much. */
1508                 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1509                         (void)BIO_flush(s->wbio);
1510
1511                 if (s->msg_callback)
1512                         s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1513
1514                 if (s->info_callback != NULL)
1515                         cb=s->info_callback;
1516                 else if (s->ctx->info_callback != NULL)
1517                         cb=s->ctx->info_callback;
1518
1519                 if (cb != NULL)
1520                         {
1521                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1522                         cb(s,SSL_CB_WRITE_ALERT,j);
1523                         }
1524                 }
1525         return(i);
1526         }