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[thirdparty/openssl.git] / ssl / s3_pkt.c
1 /* ssl/s3_pkt.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3 * All rights reserved.
4 *
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
8 *
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 *
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
22 *
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
25 * are met:
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 *
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51 * SUCH DAMAGE.
52 *
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
57 */
58 /* ====================================================================
59 * Copyright (c) 1998-2002 The OpenSSL Project. All rights reserved.
60 *
61 * Redistribution and use in source and binary forms, with or without
62 * modification, are permitted provided that the following conditions
63 * are met:
64 *
65 * 1. Redistributions of source code must retain the above copyright
66 * notice, this list of conditions and the following disclaimer.
67 *
68 * 2. Redistributions in binary form must reproduce the above copyright
69 * notice, this list of conditions and the following disclaimer in
70 * the documentation and/or other materials provided with the
71 * distribution.
72 *
73 * 3. All advertising materials mentioning features or use of this
74 * software must display the following acknowledgment:
75 * "This product includes software developed by the OpenSSL Project
76 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
77 *
78 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
79 * endorse or promote products derived from this software without
80 * prior written permission. For written permission, please contact
81 * openssl-core@openssl.org.
82 *
83 * 5. Products derived from this software may not be called "OpenSSL"
84 * nor may "OpenSSL" appear in their names without prior written
85 * permission of the OpenSSL Project.
86 *
87 * 6. Redistributions of any form whatsoever must retain the following
88 * acknowledgment:
89 * "This product includes software developed by the OpenSSL Project
90 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
91 *
92 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
93 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
94 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
95 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
96 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
97 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
98 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
99 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
100 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
101 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
102 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
103 * OF THE POSSIBILITY OF SUCH DAMAGE.
104 * ====================================================================
105 *
106 * This product includes cryptographic software written by Eric Young
107 * (eay@cryptsoft.com). This product includes software written by Tim
108 * Hudson (tjh@cryptsoft.com).
109 *
110 */
111
112 #include <stdio.h>
113 #include <errno.h>
114 #define USE_SOCKETS
115 #include "ssl_locl.h"
116 #include <openssl/evp.h>
117 #include <openssl/buffer.h>
118 #include <openssl/rand.h>
119
120 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
121 unsigned int len, int create_empty_fragment);
122 static int ssl3_get_record(SSL *s);
123
124 int ssl3_read_n(SSL *s, int n, int max, int extend)
125 {
126 /* If extend == 0, obtain new n-byte packet; if extend == 1, increase
127 * packet by another n bytes.
128 * The packet will be in the sub-array of s->s3->rbuf.buf specified
129 * by s->packet and s->packet_length.
130 * (If s->read_ahead is set, 'max' bytes may be stored in rbuf
131 * [plus s->packet_length bytes if extend == 1].)
132 */
133 int i,len,left;
134 long align=0;
135 unsigned char *pkt;
136 SSL3_BUFFER *rb;
137
138 if (n <= 0) return n;
139
140 rb = &(s->s3->rbuf);
141 if (rb->buf == NULL)
142 if (!ssl3_setup_read_buffer(s))
143 return -1;
144
145 left = rb->left;
146 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
147 align = (long)rb->buf + SSL3_RT_HEADER_LENGTH;
148 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
149 #endif
150
151 if (!extend)
152 {
153 /* start with empty packet ... */
154 if (left == 0)
155 rb->offset = align;
156 else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH)
157 {
158 /* check if next packet length is large
159 * enough to justify payload alignment... */
160 pkt = rb->buf + rb->offset;
161 if (pkt[0] == SSL3_RT_APPLICATION_DATA
162 && (pkt[3]<<8|pkt[4]) >= 128)
163 {
164 /* Note that even if packet is corrupted
165 * and its length field is insane, we can
166 * only be led to wrong decision about
167 * whether memmove will occur or not.
168 * Header values has no effect on memmove
169 * arguments and therefore no buffer
170 * overrun can be triggered. */
171 memmove (rb->buf+align,pkt,left);
172 rb->offset = align;
173 }
174 }
175 s->packet = rb->buf + rb->offset;
176 s->packet_length = 0;
177 /* ... now we can act as if 'extend' was set */
178 }
179
180 /* For DTLS/UDP reads should not span multiple packets
181 * because the read operation returns the whole packet
182 * at once (as long as it fits into the buffer). */
183 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER)
184 {
185 if (left > 0 && n > left)
186 n = left;
187 }
188
189 /* if there is enough in the buffer from a previous read, take some */
190 if (left >= n)
191 {
192 s->packet_length+=n;
193 rb->left=left-n;
194 rb->offset+=n;
195 return(n);
196 }
197
198 /* else we need to read more data */
199
200 len = s->packet_length;
201 pkt = rb->buf+align;
202 /* Move any available bytes to front of buffer:
203 * 'len' bytes already pointed to by 'packet',
204 * 'left' extra ones at the end */
205 if (s->packet != pkt) /* len > 0 */
206 {
207 memmove(pkt, s->packet, len+left);
208 s->packet = pkt;
209 rb->offset = len + align;
210 }
211
212 if (n > (int)(rb->len - rb->offset)) /* does not happen */
213 {
214 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
215 return -1;
216 }
217
218 if (!s->read_ahead)
219 /* ignore max parameter */
220 max = n;
221 else
222 {
223 if (max < n)
224 max = n;
225 if (max > (int)(rb->len - rb->offset))
226 max = rb->len - rb->offset;
227 }
228
229 while (left < n)
230 {
231 /* Now we have len+left bytes at the front of s->s3->rbuf.buf
232 * and need to read in more until we have len+n (up to
233 * len+max if possible) */
234
235 clear_sys_error();
236 if (s->rbio != NULL)
237 {
238 s->rwstate=SSL_READING;
239 i=BIO_read(s->rbio,pkt+len+left, max-left);
240 }
241 else
242 {
243 SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
244 i = -1;
245 }
246
247 if (i <= 0)
248 {
249 rb->left = left;
250 if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
251 SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
252 if (len+left == 0)
253 ssl3_release_read_buffer(s);
254 return(i);
255 }
256 left+=i;
257 /* reads should *never* span multiple packets for DTLS because
258 * the underlying transport protocol is message oriented as opposed
259 * to byte oriented as in the TLS case. */
260 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER)
261 {
262 if (n > left)
263 n = left; /* makes the while condition false */
264 }
265 }
266
267 /* done reading, now the book-keeping */
268 rb->offset += n;
269 rb->left = left - n;
270 s->packet_length += n;
271 s->rwstate=SSL_NOTHING;
272 return(n);
273 }
274
275 /* Call this to get a new input record.
276 * It will return <= 0 if more data is needed, normally due to an error
277 * or non-blocking IO.
278 * When it finishes, one packet has been decoded and can be found in
279 * ssl->s3->rrec.type - is the type of record
280 * ssl->s3->rrec.data, - data
281 * ssl->s3->rrec.length, - number of bytes
282 */
283 /* used only by ssl3_read_bytes */
284 static int ssl3_get_record(SSL *s)
285 {
286 int ssl_major,ssl_minor,al;
287 int enc_err,n,i,ret= -1;
288 SSL3_RECORD *rr;
289 SSL_SESSION *sess;
290 unsigned char *p;
291 unsigned char md[EVP_MAX_MD_SIZE];
292 short version;
293 int mac_size;
294 int clear=0;
295 size_t extra;
296 int decryption_failed_or_bad_record_mac = 0;
297 unsigned char *mac = NULL;
298
299 rr= &(s->s3->rrec);
300 sess=s->session;
301
302 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
303 extra=SSL3_RT_MAX_EXTRA;
304 else
305 extra=0;
306 if (extra && !s->s3->init_extra)
307 {
308 /* An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER
309 * set after ssl3_setup_buffers() was done */
310 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
311 return -1;
312 }
313
314 again:
315 /* check if we have the header */
316 if ( (s->rstate != SSL_ST_READ_BODY) ||
317 (s->packet_length < SSL3_RT_HEADER_LENGTH))
318 {
319 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
320 if (n <= 0) return(n); /* error or non-blocking */
321 s->rstate=SSL_ST_READ_BODY;
322
323 p=s->packet;
324
325 /* Pull apart the header into the SSL3_RECORD */
326 rr->type= *(p++);
327 ssl_major= *(p++);
328 ssl_minor= *(p++);
329 version=(ssl_major<<8)|ssl_minor;
330 n2s(p,rr->length);
331 #if 0
332 fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length);
333 #endif
334
335 /* Lets check version */
336 if (!s->first_packet)
337 {
338 if (version != s->version)
339 {
340 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
341 if ((s->version & 0xFF00) == (version & 0xFF00))
342 /* Send back error using their minor version number :-) */
343 s->version = (unsigned short)version;
344 al=SSL_AD_PROTOCOL_VERSION;
345 goto f_err;
346 }
347 }
348
349 if ((version>>8) != SSL3_VERSION_MAJOR)
350 {
351 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
352 goto err;
353 }
354
355 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH)
356 {
357 al=SSL_AD_RECORD_OVERFLOW;
358 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
359 goto f_err;
360 }
361
362 /* now s->rstate == SSL_ST_READ_BODY */
363 }
364
365 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
366
367 if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
368 {
369 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
370 i=rr->length;
371 n=ssl3_read_n(s,i,i,1);
372 if (n <= 0) return(n); /* error or non-blocking io */
373 /* now n == rr->length,
374 * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
375 }
376
377 s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
378
379 /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
380 * and we have that many bytes in s->packet
381 */
382 rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
383
384 /* ok, we can now read from 's->packet' data into 'rr'
385 * rr->input points at rr->length bytes, which
386 * need to be copied into rr->data by either
387 * the decryption or by the decompression
388 * When the data is 'copied' into the rr->data buffer,
389 * rr->input will be pointed at the new buffer */
390
391 /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
392 * rr->length bytes of encrypted compressed stuff. */
393
394 /* check is not needed I believe */
395 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
396 {
397 al=SSL_AD_RECORD_OVERFLOW;
398 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
399 goto f_err;
400 }
401
402 /* decrypt in place in 'rr->input' */
403 rr->data=rr->input;
404
405 enc_err = s->method->ssl3_enc->enc(s,0);
406 if (enc_err <= 0)
407 {
408 if (enc_err == 0)
409 /* SSLerr() and ssl3_send_alert() have been called */
410 goto err;
411
412 /* Otherwise enc_err == -1, which indicates bad padding
413 * (rec->length has not been changed in this case).
414 * To minimize information leaked via timing, we will perform
415 * the MAC computation anyway. */
416 decryption_failed_or_bad_record_mac = 1;
417 }
418
419 #ifdef TLS_DEBUG
420 printf("dec %d\n",rr->length);
421 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
422 printf("\n");
423 #endif
424
425 /* r->length is now the compressed data plus mac */
426 if ( (sess == NULL) ||
427 (s->enc_read_ctx == NULL) ||
428 (EVP_MD_CTX_md(s->read_hash) == NULL))
429 clear=1;
430
431 if (!clear)
432 {
433 /* !clear => s->read_hash != NULL => mac_size != -1 */
434 mac_size=EVP_MD_CTX_size(s->read_hash);
435 OPENSSL_assert(mac_size >= 0);
436
437 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
438 {
439 #if 0 /* OK only for stream ciphers (then rr->length is visible from ciphertext anyway) */
440 al=SSL_AD_RECORD_OVERFLOW;
441 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG);
442 goto f_err;
443 #else
444 decryption_failed_or_bad_record_mac = 1;
445 #endif
446 }
447 /* check the MAC for rr->input (it's in mac_size bytes at the tail) */
448 if (rr->length >= (unsigned int)mac_size)
449 {
450 rr->length -= mac_size;
451 mac = &rr->data[rr->length];
452 }
453 else
454 {
455 /* record (minus padding) is too short to contain a MAC */
456 #if 0 /* OK only for stream ciphers */
457 al=SSL_AD_DECODE_ERROR;
458 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
459 goto f_err;
460 #else
461 decryption_failed_or_bad_record_mac = 1;
462 rr->length = 0;
463 #endif
464 }
465 i=s->method->ssl3_enc->mac(s,md,0);
466 if (i < 0 || mac == NULL || memcmp(md, mac, (size_t)mac_size) != 0)
467 {
468 decryption_failed_or_bad_record_mac = 1;
469 }
470 }
471
472 if (decryption_failed_or_bad_record_mac)
473 {
474 /* A separate 'decryption_failed' alert was introduced with TLS 1.0,
475 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption
476 * failure is directly visible from the ciphertext anyway,
477 * we should not reveal which kind of error occured -- this
478 * might become visible to an attacker (e.g. via a logfile) */
479 al=SSL_AD_BAD_RECORD_MAC;
480 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
481 goto f_err;
482 }
483
484 /* r->length is now just compressed */
485 if (s->expand != NULL)
486 {
487 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
488 {
489 al=SSL_AD_RECORD_OVERFLOW;
490 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
491 goto f_err;
492 }
493 if (!ssl3_do_uncompress(s))
494 {
495 al=SSL_AD_DECOMPRESSION_FAILURE;
496 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
497 goto f_err;
498 }
499 }
500
501 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
502 {
503 al=SSL_AD_RECORD_OVERFLOW;
504 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
505 goto f_err;
506 }
507
508 rr->off=0;
509 /* So at this point the following is true
510 * ssl->s3->rrec.type is the type of record
511 * ssl->s3->rrec.length == number of bytes in record
512 * ssl->s3->rrec.off == offset to first valid byte
513 * ssl->s3->rrec.data == where to take bytes from, increment
514 * after use :-).
515 */
516
517 /* we have pulled in a full packet so zero things */
518 s->packet_length=0;
519
520 /* just read a 0 length packet */
521 if (rr->length == 0) goto again;
522
523 #if 0
524 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length);
525 #endif
526
527 return(1);
528
529 f_err:
530 ssl3_send_alert(s,SSL3_AL_FATAL,al);
531 err:
532 return(ret);
533 }
534
535 int ssl3_do_uncompress(SSL *ssl)
536 {
537 #ifndef OPENSSL_NO_COMP
538 int i;
539 SSL3_RECORD *rr;
540
541 rr= &(ssl->s3->rrec);
542 i=COMP_expand_block(ssl->expand,rr->comp,
543 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
544 if (i < 0)
545 return(0);
546 else
547 rr->length=i;
548 rr->data=rr->comp;
549 #endif
550 return(1);
551 }
552
553 int ssl3_do_compress(SSL *ssl)
554 {
555 #ifndef OPENSSL_NO_COMP
556 int i;
557 SSL3_RECORD *wr;
558
559 wr= &(ssl->s3->wrec);
560 i=COMP_compress_block(ssl->compress,wr->data,
561 SSL3_RT_MAX_COMPRESSED_LENGTH,
562 wr->input,(int)wr->length);
563 if (i < 0)
564 return(0);
565 else
566 wr->length=i;
567
568 wr->input=wr->data;
569 #endif
570 return(1);
571 }
572
573 /* Call this to write data in records of type 'type'
574 * It will return <= 0 if not all data has been sent or non-blocking IO.
575 */
576 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
577 {
578 const unsigned char *buf=buf_;
579 unsigned int tot,n,nw;
580 int i;
581
582 s->rwstate=SSL_NOTHING;
583 tot=s->s3->wnum;
584 s->s3->wnum=0;
585
586 if (SSL_in_init(s) && !s->in_handshake)
587 {
588 i=s->handshake_func(s);
589 if (i < 0) return(i);
590 if (i == 0)
591 {
592 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
593 return -1;
594 }
595 }
596
597 n=(len-tot);
598 for (;;)
599 {
600 if (n > s->max_send_fragment)
601 nw=s->max_send_fragment;
602 else
603 nw=n;
604
605 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
606 if (i <= 0)
607 {
608 s->s3->wnum=tot;
609 return i;
610 }
611
612 if ((i == (int)n) ||
613 (type == SSL3_RT_APPLICATION_DATA &&
614 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
615 {
616 /* next chunk of data should get another prepended empty fragment
617 * in ciphersuites with known-IV weakness: */
618 s->s3->empty_fragment_done = 0;
619
620 return tot+i;
621 }
622
623 n-=i;
624 tot+=i;
625 }
626 }
627
628 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
629 unsigned int len, int create_empty_fragment)
630 {
631 unsigned char *p,*plen;
632 int i,mac_size,clear=0;
633 int prefix_len=0;
634 int eivlen;
635 long align=0;
636 SSL3_RECORD *wr;
637 SSL3_BUFFER *wb=&(s->s3->wbuf);
638 SSL_SESSION *sess;
639
640 if (wb->buf == NULL)
641 if (!ssl3_setup_write_buffer(s))
642 return -1;
643
644 /* first check if there is a SSL3_BUFFER still being written
645 * out. This will happen with non blocking IO */
646 if (wb->left != 0)
647 return(ssl3_write_pending(s,type,buf,len));
648
649 /* If we have an alert to send, lets send it */
650 if (s->s3->alert_dispatch)
651 {
652 i=s->method->ssl_dispatch_alert(s);
653 if (i <= 0)
654 return(i);
655 /* if it went, fall through and send more stuff */
656 }
657
658 if (len == 0 && !create_empty_fragment)
659 return 0;
660
661 wr= &(s->s3->wrec);
662 sess=s->session;
663
664 if ( (sess == NULL) ||
665 (s->enc_write_ctx == NULL) ||
666 (EVP_MD_CTX_md(s->write_hash) == NULL))
667 {
668 #if 1
669 clear=s->enc_write_ctx?0:1; /* must be AEAD cipher */
670 #else
671 clear=1;
672 #endif
673 mac_size=0;
674 }
675 else
676 {
677 mac_size=EVP_MD_CTX_size(s->write_hash);
678 if (mac_size < 0)
679 goto err;
680 }
681
682 /* 'create_empty_fragment' is true only when this function calls itself */
683 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
684 {
685 /* countermeasure against known-IV weakness in CBC ciphersuites
686 * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
687
688 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
689 {
690 /* recursive function call with 'create_empty_fragment' set;
691 * this prepares and buffers the data for an empty fragment
692 * (these 'prefix_len' bytes are sent out later
693 * together with the actual payload) */
694 prefix_len = do_ssl3_write(s, type, buf, 0, 1);
695 if (prefix_len <= 0)
696 goto err;
697
698 if (prefix_len >
699 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD))
700 {
701 /* insufficient space */
702 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
703 goto err;
704 }
705 }
706
707 s->s3->empty_fragment_done = 1;
708 }
709
710 if (create_empty_fragment)
711 {
712 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
713 /* extra fragment would be couple of cipher blocks,
714 * which would be multiple of SSL3_ALIGN_PAYLOAD, so
715 * if we want to align the real payload, then we can
716 * just pretent we simply have two headers. */
717 align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH;
718 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
719 #endif
720 p = wb->buf + align;
721 wb->offset = align;
722 }
723 else if (prefix_len)
724 {
725 p = wb->buf + wb->offset + prefix_len;
726 }
727 else
728 {
729 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
730 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH;
731 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
732 #endif
733 p = wb->buf + align;
734 wb->offset = align;
735 }
736
737 /* write the header */
738
739 *(p++)=type&0xff;
740 wr->type=type;
741
742 *(p++)=(s->version>>8);
743 /* Some servers hang if iniatial client hello is larger than 256
744 * bytes and record version number > TLS 1.0
745 */
746 if (s->state == SSL3_ST_CW_CLNT_HELLO_B
747 && !s->renegotiate
748 && TLS1_get_version(s) > TLS1_VERSION)
749 *(p++) = 0x1;
750 else
751 *(p++)=s->version&0xff;
752
753 /* field where we are to write out packet length */
754 plen=p;
755 p+=2;
756 /* Explicit IV length, block ciphers and TLS version 1.1 or later */
757 if (s->enc_write_ctx && s->version >= TLS1_1_VERSION)
758 {
759 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
760 if (mode == EVP_CIPH_CBC_MODE)
761 {
762 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
763 if (eivlen <= 1)
764 eivlen = 0;
765 }
766 /* Need explicit part of IV for GCM mode */
767 else if (mode == EVP_CIPH_GCM_MODE)
768 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
769 else
770 eivlen = 0;
771 }
772 else
773 eivlen = 0;
774
775 /* lets setup the record stuff. */
776 wr->data=p + eivlen;
777 wr->length=(int)len;
778 wr->input=(unsigned char *)buf;
779
780 /* we now 'read' from wr->input, wr->length bytes into
781 * wr->data */
782
783 /* first we compress */
784 if (s->compress != NULL)
785 {
786 if (!ssl3_do_compress(s))
787 {
788 SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
789 goto err;
790 }
791 }
792 else
793 {
794 memcpy(wr->data,wr->input,wr->length);
795 wr->input=wr->data;
796 }
797
798 /* we should still have the output to wr->data and the input
799 * from wr->input. Length should be wr->length.
800 * wr->data still points in the wb->buf */
801
802 if (mac_size != 0)
803 {
804 if (s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0)
805 goto err;
806 wr->length+=mac_size;
807 }
808
809 wr->input=p;
810 wr->data=p;
811
812 if (eivlen)
813 {
814 /* if (RAND_pseudo_bytes(p, eivlen) <= 0)
815 goto err; */
816 wr->length += eivlen;
817 }
818
819 /* ssl3_enc can only have an error on read */
820 s->method->ssl3_enc->enc(s,1);
821
822 /* record length after mac and block padding */
823 s2n(wr->length,plen);
824
825 /* we should now have
826 * wr->data pointing to the encrypted data, which is
827 * wr->length long */
828 wr->type=type; /* not needed but helps for debugging */
829 wr->length+=SSL3_RT_HEADER_LENGTH;
830
831 if (create_empty_fragment)
832 {
833 /* we are in a recursive call;
834 * just return the length, don't write out anything here
835 */
836 return wr->length;
837 }
838
839 /* now let's set up wb */
840 wb->left = prefix_len + wr->length;
841
842 /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
843 s->s3->wpend_tot=len;
844 s->s3->wpend_buf=buf;
845 s->s3->wpend_type=type;
846 s->s3->wpend_ret=len;
847
848 /* we now just need to write the buffer */
849 return ssl3_write_pending(s,type,buf,len);
850 err:
851 return -1;
852 }
853
854 /* if s->s3->wbuf.left != 0, we need to call this */
855 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
856 unsigned int len)
857 {
858 int i;
859 SSL3_BUFFER *wb=&(s->s3->wbuf);
860
861 /* XXXX */
862 if ((s->s3->wpend_tot > (int)len)
863 || ((s->s3->wpend_buf != buf) &&
864 !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
865 || (s->s3->wpend_type != type))
866 {
867 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
868 return(-1);
869 }
870
871 for (;;)
872 {
873 clear_sys_error();
874 if (s->wbio != NULL)
875 {
876 s->rwstate=SSL_WRITING;
877 i=BIO_write(s->wbio,
878 (char *)&(wb->buf[wb->offset]),
879 (unsigned int)wb->left);
880 }
881 else
882 {
883 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
884 i= -1;
885 }
886 if (i == wb->left)
887 {
888 wb->left=0;
889 wb->offset+=i;
890 if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
891 SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
892 ssl3_release_write_buffer(s);
893 s->rwstate=SSL_NOTHING;
894 return(s->s3->wpend_ret);
895 }
896 else if (i <= 0) {
897 if (s->version == DTLS1_VERSION ||
898 s->version == DTLS1_BAD_VER) {
899 /* For DTLS, just drop it. That's kind of the whole
900 point in using a datagram service */
901 wb->left = 0;
902 }
903 return(i);
904 }
905 wb->offset+=i;
906 wb->left-=i;
907 }
908 }
909
910 /* Return up to 'len' payload bytes received in 'type' records.
911 * 'type' is one of the following:
912 *
913 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
914 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
915 * - 0 (during a shutdown, no data has to be returned)
916 *
917 * If we don't have stored data to work from, read a SSL/TLS record first
918 * (possibly multiple records if we still don't have anything to return).
919 *
920 * This function must handle any surprises the peer may have for us, such as
921 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
922 * a surprise, but handled as if it were), or renegotiation requests.
923 * Also if record payloads contain fragments too small to process, we store
924 * them until there is enough for the respective protocol (the record protocol
925 * may use arbitrary fragmentation and even interleaving):
926 * Change cipher spec protocol
927 * just 1 byte needed, no need for keeping anything stored
928 * Alert protocol
929 * 2 bytes needed (AlertLevel, AlertDescription)
930 * Handshake protocol
931 * 4 bytes needed (HandshakeType, uint24 length) -- we just have
932 * to detect unexpected Client Hello and Hello Request messages
933 * here, anything else is handled by higher layers
934 * Application data protocol
935 * none of our business
936 */
937 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
938 {
939 int al,i,j,ret;
940 unsigned int n;
941 SSL3_RECORD *rr;
942 void (*cb)(const SSL *ssl,int type2,int val)=NULL;
943
944 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
945 if (!ssl3_setup_read_buffer(s))
946 return(-1);
947
948 if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) ||
949 (peek && (type != SSL3_RT_APPLICATION_DATA)))
950 {
951 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
952 return -1;
953 }
954
955 if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
956 /* (partially) satisfy request from storage */
957 {
958 unsigned char *src = s->s3->handshake_fragment;
959 unsigned char *dst = buf;
960 unsigned int k;
961
962 /* peek == 0 */
963 n = 0;
964 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
965 {
966 *dst++ = *src++;
967 len--; s->s3->handshake_fragment_len--;
968 n++;
969 }
970 /* move any remaining fragment bytes: */
971 for (k = 0; k < s->s3->handshake_fragment_len; k++)
972 s->s3->handshake_fragment[k] = *src++;
973 return n;
974 }
975
976 /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
977
978 if (!s->in_handshake && SSL_in_init(s))
979 {
980 /* type == SSL3_RT_APPLICATION_DATA */
981 i=s->handshake_func(s);
982 if (i < 0) return(i);
983 if (i == 0)
984 {
985 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
986 return(-1);
987 }
988 }
989 start:
990 s->rwstate=SSL_NOTHING;
991
992 /* s->s3->rrec.type - is the type of record
993 * s->s3->rrec.data, - data
994 * s->s3->rrec.off, - offset into 'data' for next read
995 * s->s3->rrec.length, - number of bytes. */
996 rr = &(s->s3->rrec);
997
998 /* get new packet if necessary */
999 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
1000 {
1001 ret=ssl3_get_record(s);
1002 if (ret <= 0) return(ret);
1003 }
1004
1005 /* we now have a packet which can be read and processed */
1006
1007 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
1008 * reset by ssl3_get_finished */
1009 && (rr->type != SSL3_RT_HANDSHAKE))
1010 {
1011 al=SSL_AD_UNEXPECTED_MESSAGE;
1012 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
1013 goto f_err;
1014 }
1015
1016 /* If the other end has shut down, throw anything we read away
1017 * (even in 'peek' mode) */
1018 if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
1019 {
1020 rr->length=0;
1021 s->rwstate=SSL_NOTHING;
1022 return(0);
1023 }
1024
1025
1026 if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
1027 {
1028 /* make sure that we are not getting application data when we
1029 * are doing a handshake for the first time */
1030 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
1031 (s->enc_read_ctx == NULL))
1032 {
1033 al=SSL_AD_UNEXPECTED_MESSAGE;
1034 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
1035 goto f_err;
1036 }
1037
1038 if (len <= 0) return(len);
1039
1040 if ((unsigned int)len > rr->length)
1041 n = rr->length;
1042 else
1043 n = (unsigned int)len;
1044
1045 memcpy(buf,&(rr->data[rr->off]),n);
1046 if (!peek)
1047 {
1048 rr->length-=n;
1049 rr->off+=n;
1050 if (rr->length == 0)
1051 {
1052 s->rstate=SSL_ST_READ_HEADER;
1053 rr->off=0;
1054 if (s->mode & SSL_MODE_RELEASE_BUFFERS)
1055 ssl3_release_read_buffer(s);
1056 }
1057 }
1058 return(n);
1059 }
1060
1061
1062 /* If we get here, then type != rr->type; if we have a handshake
1063 * message, then it was unexpected (Hello Request or Client Hello). */
1064
1065 /* In case of record types for which we have 'fragment' storage,
1066 * fill that so that we can process the data at a fixed place.
1067 */
1068 {
1069 unsigned int dest_maxlen = 0;
1070 unsigned char *dest = NULL;
1071 unsigned int *dest_len = NULL;
1072
1073 if (rr->type == SSL3_RT_HANDSHAKE)
1074 {
1075 dest_maxlen = sizeof s->s3->handshake_fragment;
1076 dest = s->s3->handshake_fragment;
1077 dest_len = &s->s3->handshake_fragment_len;
1078 }
1079 else if (rr->type == SSL3_RT_ALERT)
1080 {
1081 dest_maxlen = sizeof s->s3->alert_fragment;
1082 dest = s->s3->alert_fragment;
1083 dest_len = &s->s3->alert_fragment_len;
1084 }
1085 #ifndef OPENSSL_NO_HEARTBEATS
1086 else if (rr->type == TLS1_RT_HEARTBEAT)
1087 {
1088 tls1_process_heartbeat(s);
1089
1090 /* Exit and notify application to read again */
1091 rr->length = 0;
1092 s->rwstate=SSL_READING;
1093 BIO_clear_retry_flags(SSL_get_rbio(s));
1094 BIO_set_retry_read(SSL_get_rbio(s));
1095 return(-1);
1096 }
1097 #endif
1098
1099 if (dest_maxlen > 0)
1100 {
1101 n = dest_maxlen - *dest_len; /* available space in 'dest' */
1102 if (rr->length < n)
1103 n = rr->length; /* available bytes */
1104
1105 /* now move 'n' bytes: */
1106 while (n-- > 0)
1107 {
1108 dest[(*dest_len)++] = rr->data[rr->off++];
1109 rr->length--;
1110 }
1111
1112 if (*dest_len < dest_maxlen)
1113 goto start; /* fragment was too small */
1114 }
1115 }
1116
1117 /* s->s3->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE;
1118 * s->s3->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT.
1119 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
1120
1121 /* If we are a client, check for an incoming 'Hello Request': */
1122 if ((!s->server) &&
1123 (s->s3->handshake_fragment_len >= 4) &&
1124 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1125 (s->session != NULL) && (s->session->cipher != NULL))
1126 {
1127 s->s3->handshake_fragment_len = 0;
1128
1129 if ((s->s3->handshake_fragment[1] != 0) ||
1130 (s->s3->handshake_fragment[2] != 0) ||
1131 (s->s3->handshake_fragment[3] != 0))
1132 {
1133 al=SSL_AD_DECODE_ERROR;
1134 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1135 goto f_err;
1136 }
1137
1138 if (s->msg_callback)
1139 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
1140
1141 if (SSL_is_init_finished(s) &&
1142 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1143 !s->s3->renegotiate)
1144 {
1145 ssl3_renegotiate(s);
1146 if (ssl3_renegotiate_check(s))
1147 {
1148 i=s->handshake_func(s);
1149 if (i < 0) return(i);
1150 if (i == 0)
1151 {
1152 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1153 return(-1);
1154 }
1155
1156 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1157 {
1158 if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1159 {
1160 BIO *bio;
1161 /* In the case where we try to read application data,
1162 * but we trigger an SSL handshake, we return -1 with
1163 * the retry option set. Otherwise renegotiation may
1164 * cause nasty problems in the blocking world */
1165 s->rwstate=SSL_READING;
1166 bio=SSL_get_rbio(s);
1167 BIO_clear_retry_flags(bio);
1168 BIO_set_retry_read(bio);
1169 return(-1);
1170 }
1171 }
1172 }
1173 }
1174 /* we either finished a handshake or ignored the request,
1175 * now try again to obtain the (application) data we were asked for */
1176 goto start;
1177 }
1178 /* If we are a server and get a client hello when renegotiation isn't
1179 * allowed send back a no renegotiation alert and carry on.
1180 * WARNING: experimental code, needs reviewing (steve)
1181 */
1182 if (s->server &&
1183 SSL_is_init_finished(s) &&
1184 !s->s3->send_connection_binding &&
1185 (s->version > SSL3_VERSION) &&
1186 (s->s3->handshake_fragment_len >= 4) &&
1187 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1188 (s->session != NULL) && (s->session->cipher != NULL) &&
1189 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1190
1191 {
1192 /*s->s3->handshake_fragment_len = 0;*/
1193 rr->length = 0;
1194 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1195 goto start;
1196 }
1197 if (s->s3->alert_fragment_len >= 2)
1198 {
1199 int alert_level = s->s3->alert_fragment[0];
1200 int alert_descr = s->s3->alert_fragment[1];
1201
1202 s->s3->alert_fragment_len = 0;
1203
1204 if (s->msg_callback)
1205 s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1206
1207 if (s->info_callback != NULL)
1208 cb=s->info_callback;
1209 else if (s->ctx->info_callback != NULL)
1210 cb=s->ctx->info_callback;
1211
1212 if (cb != NULL)
1213 {
1214 j = (alert_level << 8) | alert_descr;
1215 cb(s, SSL_CB_READ_ALERT, j);
1216 }
1217
1218 if (alert_level == 1) /* warning */
1219 {
1220 s->s3->warn_alert = alert_descr;
1221 if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1222 {
1223 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1224 return(0);
1225 }
1226 /* This is a warning but we receive it if we requested
1227 * renegotiation and the peer denied it. Terminate with
1228 * a fatal alert because if application tried to
1229 * renegotiatie it presumably had a good reason and
1230 * expects it to succeed.
1231 *
1232 * In future we might have a renegotiation where we
1233 * don't care if the peer refused it where we carry on.
1234 */
1235 else if (alert_descr == SSL_AD_NO_RENEGOTIATION)
1236 {
1237 al = SSL_AD_HANDSHAKE_FAILURE;
1238 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION);
1239 goto f_err;
1240 }
1241 #ifdef SSL_AD_MISSING_SRP_USERNAME
1242 else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME)
1243 return(0);
1244 #endif
1245 }
1246 else if (alert_level == 2) /* fatal */
1247 {
1248 char tmp[16];
1249
1250 s->rwstate=SSL_NOTHING;
1251 s->s3->fatal_alert = alert_descr;
1252 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1253 BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1254 ERR_add_error_data(2,"SSL alert number ",tmp);
1255 s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1256 SSL_CTX_remove_session(s->ctx,s->session);
1257 return(0);
1258 }
1259 else
1260 {
1261 al=SSL_AD_ILLEGAL_PARAMETER;
1262 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1263 goto f_err;
1264 }
1265
1266 goto start;
1267 }
1268
1269 if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1270 {
1271 s->rwstate=SSL_NOTHING;
1272 rr->length=0;
1273 return(0);
1274 }
1275
1276 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1277 {
1278 /* 'Change Cipher Spec' is just a single byte, so we know
1279 * exactly what the record payload has to look like */
1280 if ( (rr->length != 1) || (rr->off != 0) ||
1281 (rr->data[0] != SSL3_MT_CCS))
1282 {
1283 al=SSL_AD_ILLEGAL_PARAMETER;
1284 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1285 goto f_err;
1286 }
1287
1288 /* Check we have a cipher to change to */
1289 if (s->s3->tmp.new_cipher == NULL)
1290 {
1291 al=SSL_AD_UNEXPECTED_MESSAGE;
1292 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1293 goto f_err;
1294 }
1295
1296 rr->length=0;
1297
1298 if (s->msg_callback)
1299 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1300
1301 s->s3->change_cipher_spec=1;
1302 if (!ssl3_do_change_cipher_spec(s))
1303 goto err;
1304 else
1305 goto start;
1306 }
1307
1308 /* Unexpected handshake message (Client Hello, or protocol violation) */
1309 if ((s->s3->handshake_fragment_len >= 4) && !s->in_handshake)
1310 {
1311 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1312 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1313 {
1314 #if 0 /* worked only because C operator preferences are not as expected (and
1315 * because this is not really needed for clients except for detecting
1316 * protocol violations): */
1317 s->state=SSL_ST_BEFORE|(s->server)
1318 ?SSL_ST_ACCEPT
1319 :SSL_ST_CONNECT;
1320 #else
1321 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1322 #endif
1323 s->renegotiate=1;
1324 s->new_session=1;
1325 }
1326 i=s->handshake_func(s);
1327 if (i < 0) return(i);
1328 if (i == 0)
1329 {
1330 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1331 return(-1);
1332 }
1333
1334 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1335 {
1336 if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1337 {
1338 BIO *bio;
1339 /* In the case where we try to read application data,
1340 * but we trigger an SSL handshake, we return -1 with
1341 * the retry option set. Otherwise renegotiation may
1342 * cause nasty problems in the blocking world */
1343 s->rwstate=SSL_READING;
1344 bio=SSL_get_rbio(s);
1345 BIO_clear_retry_flags(bio);
1346 BIO_set_retry_read(bio);
1347 return(-1);
1348 }
1349 }
1350 goto start;
1351 }
1352
1353 switch (rr->type)
1354 {
1355 default:
1356 #ifndef OPENSSL_NO_TLS
1357 /* TLS up to v1.1 just ignores unknown message types:
1358 * TLS v1.2 give an unexpected message alert.
1359 */
1360 if (s->version >= TLS1_VERSION && s->version <= TLS1_1_VERSION)
1361 {
1362 rr->length = 0;
1363 goto start;
1364 }
1365 #endif
1366 al=SSL_AD_UNEXPECTED_MESSAGE;
1367 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1368 goto f_err;
1369 case SSL3_RT_CHANGE_CIPHER_SPEC:
1370 case SSL3_RT_ALERT:
1371 case SSL3_RT_HANDSHAKE:
1372 /* we already handled all of these, with the possible exception
1373 * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1374 * should not happen when type != rr->type */
1375 al=SSL_AD_UNEXPECTED_MESSAGE;
1376 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1377 goto f_err;
1378 case SSL3_RT_APPLICATION_DATA:
1379 /* At this point, we were expecting handshake data,
1380 * but have application data. If the library was
1381 * running inside ssl3_read() (i.e. in_read_app_data
1382 * is set) and it makes sense to read application data
1383 * at this point (session renegotiation not yet started),
1384 * we will indulge it.
1385 */
1386 if (s->s3->in_read_app_data &&
1387 (s->s3->total_renegotiations != 0) &&
1388 ((
1389 (s->state & SSL_ST_CONNECT) &&
1390 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1391 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1392 ) || (
1393 (s->state & SSL_ST_ACCEPT) &&
1394 (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1395 (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1396 )
1397 ))
1398 {
1399 s->s3->in_read_app_data=2;
1400 return(-1);
1401 }
1402 else
1403 {
1404 al=SSL_AD_UNEXPECTED_MESSAGE;
1405 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1406 goto f_err;
1407 }
1408 }
1409 /* not reached */
1410
1411 f_err:
1412 ssl3_send_alert(s,SSL3_AL_FATAL,al);
1413 err:
1414 return(-1);
1415 }
1416
1417 int ssl3_do_change_cipher_spec(SSL *s)
1418 {
1419 int i;
1420 const char *sender;
1421 int slen;
1422
1423 if (s->state & SSL_ST_ACCEPT)
1424 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1425 else
1426 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1427
1428 if (s->s3->tmp.key_block == NULL)
1429 {
1430 if (s->session == NULL)
1431 {
1432 /* might happen if dtls1_read_bytes() calls this */
1433 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY);
1434 return (0);
1435 }
1436
1437 s->session->cipher=s->s3->tmp.new_cipher;
1438 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1439 }
1440
1441 if (!s->method->ssl3_enc->change_cipher_state(s,i))
1442 return(0);
1443
1444 /* we have to record the message digest at
1445 * this point so we can get it before we read
1446 * the finished message */
1447 if (s->state & SSL_ST_CONNECT)
1448 {
1449 sender=s->method->ssl3_enc->server_finished_label;
1450 slen=s->method->ssl3_enc->server_finished_label_len;
1451 }
1452 else
1453 {
1454 sender=s->method->ssl3_enc->client_finished_label;
1455 slen=s->method->ssl3_enc->client_finished_label_len;
1456 }
1457
1458 s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1459 sender,slen,s->s3->tmp.peer_finish_md);
1460
1461 return(1);
1462 }
1463
1464 int ssl3_send_alert(SSL *s, int level, int desc)
1465 {
1466 /* Map tls/ssl alert value to correct one */
1467 desc=s->method->ssl3_enc->alert_value(desc);
1468 if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1469 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1470 if (desc < 0) return -1;
1471 /* If a fatal one, remove from cache */
1472 if ((level == 2) && (s->session != NULL))
1473 SSL_CTX_remove_session(s->ctx,s->session);
1474
1475 s->s3->alert_dispatch=1;
1476 s->s3->send_alert[0]=level;
1477 s->s3->send_alert[1]=desc;
1478 if (s->s3->wbuf.left == 0) /* data still being written out? */
1479 return s->method->ssl_dispatch_alert(s);
1480 /* else data is still being written out, we will get written
1481 * some time in the future */
1482 return -1;
1483 }
1484
1485 int ssl3_dispatch_alert(SSL *s)
1486 {
1487 int i,j;
1488 void (*cb)(const SSL *ssl,int type,int val)=NULL;
1489
1490 s->s3->alert_dispatch=0;
1491 i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1492 if (i <= 0)
1493 {
1494 s->s3->alert_dispatch=1;
1495 }
1496 else
1497 {
1498 /* Alert sent to BIO. If it is important, flush it now.
1499 * If the message does not get sent due to non-blocking IO,
1500 * we will not worry too much. */
1501 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1502 (void)BIO_flush(s->wbio);
1503
1504 if (s->msg_callback)
1505 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1506
1507 if (s->info_callback != NULL)
1508 cb=s->info_callback;
1509 else if (s->ctx->info_callback != NULL)
1510 cb=s->ctx->info_callback;
1511
1512 if (cb != NULL)
1513 {
1514 j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1515 cb(s,SSL_CB_WRITE_ALERT,j);
1516 }
1517 }
1518 return(i);
1519 }
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