1 /* ssl/d1_pkt.c */
2 /*
3 * DTLS implementation written by Nagendra Modadugu
4 * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
5 */
6 /* ====================================================================
7 * Copyright (c) 1998-2005 The OpenSSL Project. All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 *
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 *
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in
18 * the documentation and/or other materials provided with the
19 * distribution.
20 *
21 * 3. All advertising materials mentioning features or use of this
22 * software must display the following acknowledgment:
23 * "This product includes software developed by the OpenSSL Project
24 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
25 *
26 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
27 * endorse or promote products derived from this software without
28 * prior written permission. For written permission, please contact
29 * openssl-core@openssl.org.
30 *
31 * 5. Products derived from this software may not be called "OpenSSL"
32 * nor may "OpenSSL" appear in their names without prior written
33 * permission of the OpenSSL Project.
34 *
35 * 6. Redistributions of any form whatsoever must retain the following
36 * acknowledgment:
37 * "This product includes software developed by the OpenSSL Project
38 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
39 *
40 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
41 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
43 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
44 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
45 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
46 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
47 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
49 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
50 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
51 * OF THE POSSIBILITY OF SUCH DAMAGE.
52 * ====================================================================
53 *
54 * This product includes cryptographic software written by Eric Young
55 * (eay@cryptsoft.com). This product includes software written by Tim
56 * Hudson (tjh@cryptsoft.com).
57 *
58 */
59 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
60 * All rights reserved.
61 *
62 * This package is an SSL implementation written
63 * by Eric Young (eay@cryptsoft.com).
64 * The implementation was written so as to conform with Netscapes SSL.
65 *
66 * This library is free for commercial and non-commercial use as long as
67 * the following conditions are aheared to. The following conditions
68 * apply to all code found in this distribution, be it the RC4, RSA,
69 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
70 * included with this distribution is covered by the same copyright terms
71 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
72 *
73 * Copyright remains Eric Young's, and as such any Copyright notices in
74 * the code are not to be removed.
75 * If this package is used in a product, Eric Young should be given attribution
76 * as the author of the parts of the library used.
77 * This can be in the form of a textual message at program startup or
78 * in documentation (online or textual) provided with the package.
79 *
80 * Redistribution and use in source and binary forms, with or without
81 * modification, are permitted provided that the following conditions
82 * are met:
83 * 1. Redistributions of source code must retain the copyright
84 * notice, this list of conditions and the following disclaimer.
85 * 2. Redistributions in binary form must reproduce the above copyright
86 * notice, this list of conditions and the following disclaimer in the
87 * documentation and/or other materials provided with the distribution.
88 * 3. All advertising materials mentioning features or use of this software
89 * must display the following acknowledgement:
90 * "This product includes cryptographic software written by
91 * Eric Young (eay@cryptsoft.com)"
92 * The word 'cryptographic' can be left out if the rouines from the library
93 * being used are not cryptographic related :-).
94 * 4. If you include any Windows specific code (or a derivative thereof) from
95 * the apps directory (application code) you must include an acknowledgement:
96 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
97 *
98 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
99 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
100 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
101 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
102 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
103 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
104 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
105 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
106 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
107 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
108 * SUCH DAMAGE.
109 *
110 * The licence and distribution terms for any publically available version or
111 * derivative of this code cannot be changed. i.e. this code cannot simply be
112 * copied and put under another distribution licence
113 * [including the GNU Public Licence.]
114 */
115
116 #include <stdio.h>
117 #include <errno.h>
118 #define USE_SOCKETS
119 #include "ssl_locl.h"
120 #include <openssl/evp.h>
121 #include <openssl/buffer.h>
122 #include <openssl/pqueue.h>
123 #include <openssl/rand.h>
124
125 /* mod 128 saturating subtract of two 64-bit values in big-endian order */
satsub64be(const unsigned char * v1,const unsigned char * v2)126 static int satsub64be(const unsigned char *v1, const unsigned char *v2)
127 {
128 int ret, sat, brw, i;
129
130 if (sizeof(long) == 8)
131 do {
132 const union {
133 long one;
134 char little;
135 } is_endian = {
136 1
137 };
138 long l;
139
140 if (is_endian.little)
141 break;
142 /* not reached on little-endians */
143 /*
144 * following test is redundant, because input is always aligned,
145 * but I take no chances...
146 */
147 if (((size_t)v1 | (size_t)v2) & 0x7)
148 break;
149
150 l = *((long *)v1);
151 l -= *((long *)v2);
152 if (l > 128)
153 return 128;
154 else if (l < -128)
155 return -128;
156 else
157 return (int)l;
158 } while (0);
159
160 ret = (int)v1[7] - (int)v2[7];
161 sat = 0;
162 brw = ret >> 8; /* brw is either 0 or -1 */
163 if (ret & 0x80) {
164 for (i = 6; i >= 0; i--) {
165 brw += (int)v1[i] - (int)v2[i];
166 sat |= ~brw;
167 brw >>= 8;
168 }
169 } else {
170 for (i = 6; i >= 0; i--) {
171 brw += (int)v1[i] - (int)v2[i];
172 sat |= brw;
173 brw >>= 8;
174 }
175 }
176 brw <<= 8; /* brw is either 0 or -256 */
177
178 if (sat & 0xff)
179 return brw | 0x80;
180 else
181 return brw + (ret & 0xFF);
182 }
183
184 static int have_handshake_fragment(SSL *s, int type, unsigned char *buf,
185 int len, int peek);
186 static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap);
187 static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap);
188 static DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr,
189 unsigned int *is_next_epoch);
190 #if 0
191 static int dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr,
192 unsigned short *priority,
193 unsigned long *offset);
194 #endif
195 static int dtls1_buffer_record(SSL *s, record_pqueue *q,
196 unsigned char *priority);
197 static int dtls1_process_record(SSL *s, DTLS1_BITMAP *bitmap);
198
199 /* copy buffered record into SSL structure */
dtls1_copy_record(SSL * s,pitem * item)200 static int dtls1_copy_record(SSL *s, pitem *item)
201 {
202 DTLS1_RECORD_DATA *rdata;
203
204 rdata = (DTLS1_RECORD_DATA *)item->data;
205
206 if (s->s3->rbuf.buf != NULL)
207 OPENSSL_free(s->s3->rbuf.buf);
208
209 s->packet = rdata->packet;
210 s->packet_length = rdata->packet_length;
211 memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER));
212 memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD));
213
214 /* Set proper sequence number for mac calculation */
215 memcpy(&(s->s3->read_sequence[2]), &(rdata->packet[5]), 6);
216
217 return (1);
218 }
219
220 static int
dtls1_buffer_record(SSL * s,record_pqueue * queue,unsigned char * priority)221 dtls1_buffer_record(SSL *s, record_pqueue *queue, unsigned char *priority)
222 {
223 DTLS1_RECORD_DATA *rdata;
224 pitem *item;
225
226 /* Limit the size of the queue to prevent DOS attacks */
227 if (pqueue_size(queue->q) >= 100)
228 return 0;
229
230 rdata = OPENSSL_malloc(sizeof(DTLS1_RECORD_DATA));
231 item = pitem_new(priority, rdata);
232 if (rdata == NULL || item == NULL) {
233 if (rdata != NULL)
234 OPENSSL_free(rdata);
235 if (item != NULL)
236 pitem_free(item);
237
238 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
239 return -1;
240 }
241
242 rdata->packet = s->packet;
243 rdata->packet_length = s->packet_length;
244 memcpy(&(rdata->rbuf), &(s->s3->rbuf), sizeof(SSL3_BUFFER));
245 memcpy(&(rdata->rrec), &(s->s3->rrec), sizeof(SSL3_RECORD));
246
247 item->data = rdata;
248
249 #ifndef OPENSSL_NO_SCTP
250 /* Store bio_dgram_sctp_rcvinfo struct */
251 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
252 (s->state == SSL3_ST_SR_FINISHED_A
253 || s->state == SSL3_ST_CR_FINISHED_A)) {
254 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_GET_RCVINFO,
255 sizeof(rdata->recordinfo), &rdata->recordinfo);
256 }
257 #endif
258
259 s->packet = NULL;
260 s->packet_length = 0;
261 memset(&(s->s3->rbuf), 0, sizeof(SSL3_BUFFER));
262 memset(&(s->s3->rrec), 0, sizeof(SSL3_RECORD));
263
264 if (!ssl3_setup_buffers(s)) {
265 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
266 if (rdata->rbuf.buf != NULL)
267 OPENSSL_free(rdata->rbuf.buf);
268 OPENSSL_free(rdata);
269 pitem_free(item);
270 return (-1);
271 }
272
273 /* insert should not fail, since duplicates are dropped */
274 if (pqueue_insert(queue->q, item) == NULL) {
275 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
276 if (rdata->rbuf.buf != NULL)
277 OPENSSL_free(rdata->rbuf.buf);
278 OPENSSL_free(rdata);
279 pitem_free(item);
280 return (-1);
281 }
282
283 return (1);
284 }
285
dtls1_retrieve_buffered_record(SSL * s,record_pqueue * queue)286 static int dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue)
287 {
288 pitem *item;
289
290 item = pqueue_pop(queue->q);
291 if (item) {
292 dtls1_copy_record(s, item);
293
294 OPENSSL_free(item->data);
295 pitem_free(item);
296
297 return (1);
298 }
299
300 return (0);
301 }
302
303 /*
304 * retrieve a buffered record that belongs to the new epoch, i.e., not
305 * processed yet
306 */
307 #define dtls1_get_unprocessed_record(s) \
308 dtls1_retrieve_buffered_record((s), \
309 &((s)->d1->unprocessed_rcds))
310
311 /*
312 * retrieve a buffered record that belongs to the current epoch, ie,
313 * processed
314 */
315 #define dtls1_get_processed_record(s) \
316 dtls1_retrieve_buffered_record((s), \
317 &((s)->d1->processed_rcds))
318
dtls1_process_buffered_records(SSL * s)319 static int dtls1_process_buffered_records(SSL *s)
320 {
321 pitem *item;
322 SSL3_BUFFER *rb;
323 SSL3_RECORD *rr;
324 DTLS1_BITMAP *bitmap;
325 unsigned int is_next_epoch;
326 int replayok = 1;
327
328 item = pqueue_peek(s->d1->unprocessed_rcds.q);
329 if (item) {
330 /* Check if epoch is current. */
331 if (s->d1->unprocessed_rcds.epoch != s->d1->r_epoch)
332 return 1; /* Nothing to do. */
333
334 rr = &s->s3->rrec;
335 rb = &s->s3->rbuf;
336
337 if (rb->left > 0) {
338 /*
339 * We've still got data from the current packet to read. There could
340 * be a record from the new epoch in it - so don't overwrite it
341 * with the unprocessed records yet (we'll do it when we've
342 * finished reading the current packet).
343 */
344 return 1;
345 }
346
347
348 /* Process all the records. */
349 while (pqueue_peek(s->d1->unprocessed_rcds.q)) {
350 dtls1_get_unprocessed_record(s);
351 bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch);
352 if (bitmap == NULL) {
353 /*
354 * Should not happen. This will only ever be NULL when the
355 * current record is from a different epoch. But that cannot
356 * be the case because we already checked the epoch above
357 */
358 SSLerr(SSL_F_DTLS1_PROCESS_BUFFERED_RECORDS,
359 ERR_R_INTERNAL_ERROR);
360 return 0;
361 }
362 #ifndef OPENSSL_NO_SCTP
363 /* Only do replay check if no SCTP bio */
364 if (!BIO_dgram_is_sctp(SSL_get_rbio(s)))
365 #endif
366 {
367 /*
368 * Check whether this is a repeat, or aged record. We did this
369 * check once already when we first received the record - but
370 * we might have updated the window since then due to
371 * records we subsequently processed.
372 */
373 replayok = dtls1_record_replay_check(s, bitmap);
374 }
375
376 if (!replayok || !dtls1_process_record(s, bitmap)) {
377 /* dump this record */
378 rr->length = 0;
379 s->packet_length = 0;
380 continue;
381 }
382
383 if (dtls1_buffer_record(s, &(s->d1->processed_rcds),
384 s->s3->rrec.seq_num) < 0)
385 return 0;
386 }
387 }
388
389 /*
390 * sync epoch numbers once all the unprocessed records have been
391 * processed
392 */
393 s->d1->processed_rcds.epoch = s->d1->r_epoch;
394 s->d1->unprocessed_rcds.epoch = s->d1->r_epoch + 1;
395
396 return 1;
397 }
398
399 #if 0
400
401 static int dtls1_get_buffered_record(SSL *s)
402 {
403 pitem *item;
404 PQ_64BIT priority =
405 (((PQ_64BIT) s->d1->handshake_read_seq) << 32) |
406 ((PQ_64BIT) s->d1->r_msg_hdr.frag_off);
407
408 /* if we're not (re)negotiating, nothing buffered */
409 if (!SSL_in_init(s))
410 return 0;
411
412 item = pqueue_peek(s->d1->rcvd_records);
413 if (item && item->priority == priority) {
414 /*
415 * Check if we've received the record of interest. It must be a
416 * handshake record, since data records as passed up without
417 * buffering
418 */
419 DTLS1_RECORD_DATA *rdata;
420 item = pqueue_pop(s->d1->rcvd_records);
421 rdata = (DTLS1_RECORD_DATA *)item->data;
422
423 if (s->s3->rbuf.buf != NULL)
424 OPENSSL_free(s->s3->rbuf.buf);
425
426 s->packet = rdata->packet;
427 s->packet_length = rdata->packet_length;
428 memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER));
429 memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD));
430
431 OPENSSL_free(item->data);
432 pitem_free(item);
433
434 /* s->d1->next_expected_seq_num++; */
435 return (1);
436 }
437
438 return 0;
439 }
440
441 #endif
442
dtls1_process_record(SSL * s,DTLS1_BITMAP * bitmap)443 static int dtls1_process_record(SSL *s, DTLS1_BITMAP *bitmap)
444 {
445 int i, al;
446 int enc_err;
447 SSL_SESSION *sess;
448 SSL3_RECORD *rr;
449 unsigned int mac_size, orig_len;
450 unsigned char md[EVP_MAX_MD_SIZE];
451
452 rr = &(s->s3->rrec);
453 sess = s->session;
454
455 /*
456 * At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
457 * and we have that many bytes in s->packet
458 */
459 rr->input = &(s->packet[DTLS1_RT_HEADER_LENGTH]);
460
461 /*
462 * ok, we can now read from 's->packet' data into 'rr' rr->input points
463 * at rr->length bytes, which need to be copied into rr->data by either
464 * the decryption or by the decompression When the data is 'copied' into
465 * the rr->data buffer, rr->input will be pointed at the new buffer
466 */
467
468 /*
469 * We now have - encrypted [ MAC [ compressed [ plain ] ] ] rr->length
470 * bytes of encrypted compressed stuff.
471 */
472
473 /* check is not needed I believe */
474 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) {
475 al = SSL_AD_RECORD_OVERFLOW;
476 SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
477 goto f_err;
478 }
479
480 /* decrypt in place in 'rr->input' */
481 rr->data = rr->input;
482
483 enc_err = s->method->ssl3_enc->enc(s, 0);
484 /*-
485 * enc_err is:
486 * 0: (in non-constant time) if the record is publically invalid.
487 * 1: if the padding is valid
488 * -1: if the padding is invalid
489 */
490 if (enc_err == 0) {
491 /* For DTLS we simply ignore bad packets. */
492 rr->length = 0;
493 s->packet_length = 0;
494 goto err;
495 }
496 #ifdef TLS_DEBUG
497 printf("dec %d\n", rr->length);
498 {
499 unsigned int z;
500 for (z = 0; z < rr->length; z++)
501 printf("%02X%c", rr->data[z], ((z + 1) % 16) ? ' ' : '\n');
502 }
503 printf("\n");
504 #endif
505
506 /* r->length is now the compressed data plus mac */
507 if ((sess != NULL) &&
508 (s->enc_read_ctx != NULL) && (EVP_MD_CTX_md(s->read_hash) != NULL)) {
509 /* s->read_hash != NULL => mac_size != -1 */
510 unsigned char *mac = NULL;
511 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
512 mac_size = EVP_MD_CTX_size(s->read_hash);
513 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
514
515 /*
516 * kludge: *_cbc_remove_padding passes padding length in rr->type
517 */
518 orig_len = rr->length + ((unsigned int)rr->type >> 8);
519
520 /*
521 * orig_len is the length of the record before any padding was
522 * removed. This is public information, as is the MAC in use,
523 * therefore we can safely process the record in a different amount
524 * of time if it's too short to possibly contain a MAC.
525 */
526 if (orig_len < mac_size ||
527 /* CBC records must have a padding length byte too. */
528 (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
529 orig_len < mac_size + 1)) {
530 al = SSL_AD_DECODE_ERROR;
531 SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_LENGTH_TOO_SHORT);
532 goto f_err;
533 }
534
535 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE) {
536 /*
537 * We update the length so that the TLS header bytes can be
538 * constructed correctly but we need to extract the MAC in
539 * constant time from within the record, without leaking the
540 * contents of the padding bytes.
541 */
542 mac = mac_tmp;
543 ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
544 rr->length -= mac_size;
545 } else {
546 /*
547 * In this case there's no padding, so |orig_len| equals
548 * |rec->length| and we checked that there's enough bytes for
549 * |mac_size| above.
550 */
551 rr->length -= mac_size;
552 mac = &rr->data[rr->length];
553 }
554
555 i = s->method->ssl3_enc->mac(s, md, 0 /* not send */ );
556 if (i < 0 || mac == NULL
557 || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
558 enc_err = -1;
559 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + mac_size)
560 enc_err = -1;
561 }
562
563 if (enc_err < 0) {
564 /* decryption failed, silently discard message */
565 rr->length = 0;
566 s->packet_length = 0;
567 goto err;
568 }
569
570 /* r->length is now just compressed */
571 if (s->expand != NULL) {
572 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH) {
573 al = SSL_AD_RECORD_OVERFLOW;
574 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,
575 SSL_R_COMPRESSED_LENGTH_TOO_LONG);
576 goto f_err;
577 }
578 if (!ssl3_do_uncompress(s)) {
579 al = SSL_AD_DECOMPRESSION_FAILURE;
580 SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_BAD_DECOMPRESSION);
581 goto f_err;
582 }
583 }
584
585 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH) {
586 al = SSL_AD_RECORD_OVERFLOW;
587 SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_DATA_LENGTH_TOO_LONG);
588 goto f_err;
589 }
590
591 rr->off = 0;
592 /*-
593 * So at this point the following is true
594 * ssl->s3->rrec.type is the type of record
595 * ssl->s3->rrec.length == number of bytes in record
596 * ssl->s3->rrec.off == offset to first valid byte
597 * ssl->s3->rrec.data == where to take bytes from, increment
598 * after use :-).
599 */
600
601 /* we have pulled in a full packet so zero things */
602 s->packet_length = 0;
603
604 /* Mark receipt of record. */
605 dtls1_record_bitmap_update(s, bitmap);
606
607 return (1);
608
609 f_err:
610 ssl3_send_alert(s, SSL3_AL_FATAL, al);
611 err:
612 return (0);
613 }
614
615 /*-
616 * Call this to get a new input record.
617 * It will return <= 0 if more data is needed, normally due to an error
618 * or non-blocking IO.
619 * When it finishes, one packet has been decoded and can be found in
620 * ssl->s3->rrec.type - is the type of record
621 * ssl->s3->rrec.data, - data
622 * ssl->s3->rrec.length, - number of bytes
623 */
624 /* used only by dtls1_read_bytes */
dtls1_get_record(SSL * s)625 int dtls1_get_record(SSL *s)
626 {
627 int ssl_major, ssl_minor;
628 int i, n;
629 SSL3_RECORD *rr;
630 unsigned char *p = NULL;
631 unsigned short version;
632 DTLS1_BITMAP *bitmap;
633 unsigned int is_next_epoch;
634
635 rr = &(s->s3->rrec);
636
637 again:
638 /*
639 * The epoch may have changed. If so, process all the pending records.
640 * This is a non-blocking operation.
641 */
642 if (!dtls1_process_buffered_records(s))
643 return -1;
644
645 /* if we're renegotiating, then there may be buffered records */
646 if (dtls1_get_processed_record(s))
647 return 1;
648
649 /* get something from the wire */
650 /* check if we have the header */
651 if ((s->rstate != SSL_ST_READ_BODY) ||
652 (s->packet_length < DTLS1_RT_HEADER_LENGTH)) {
653 n = ssl3_read_n(s, DTLS1_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
654 /* read timeout is handled by dtls1_read_bytes */
655 if (n <= 0)
656 return (n); /* error or non-blocking */
657
658 /* this packet contained a partial record, dump it */
659 if (s->packet_length != DTLS1_RT_HEADER_LENGTH) {
660 s->packet_length = 0;
661 goto again;
662 }
663
664 s->rstate = SSL_ST_READ_BODY;
665
666 p = s->packet;
667
668 /* Pull apart the header into the DTLS1_RECORD */
669 rr->type = *(p++);
670 ssl_major = *(p++);
671 ssl_minor = *(p++);
672 version = (ssl_major << 8) | ssl_minor;
673
674 /* sequence number is 64 bits, with top 2 bytes = epoch */
675 n2s(p, rr->epoch);
676
677 memcpy(&(s->s3->read_sequence[2]), p, 6);
678 p += 6;
679
680 n2s(p, rr->length);
681
682 /* Lets check version */
683 if (!s->first_packet) {
684 if (version != s->version) {
685 /* unexpected version, silently discard */
686 rr->length = 0;
687 s->packet_length = 0;
688 goto again;
689 }
690 }
691
692 if ((version & 0xff00) != (s->version & 0xff00)) {
693 /* wrong version, silently discard record */
694 rr->length = 0;
695 s->packet_length = 0;
696 goto again;
697 }
698
699 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) {
700 /* record too long, silently discard it */
701 rr->length = 0;
702 s->packet_length = 0;
703 goto again;
704 }
705
706 /* now s->rstate == SSL_ST_READ_BODY */
707 }
708
709 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
710
711 if (rr->length > s->packet_length - DTLS1_RT_HEADER_LENGTH) {
712 /* now s->packet_length == DTLS1_RT_HEADER_LENGTH */
713 i = rr->length;
714 n = ssl3_read_n(s, i, i, 1);
715 /* this packet contained a partial record, dump it */
716 if (n != i) {
717 rr->length = 0;
718 s->packet_length = 0;
719 goto again;
720 }
721
722 /*
723 * now n == rr->length, and s->packet_length ==
724 * DTLS1_RT_HEADER_LENGTH + rr->length
725 */
726 }
727 s->rstate = SSL_ST_READ_HEADER; /* set state for later operations */
728
729 /* match epochs. NULL means the packet is dropped on the floor */
730 bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch);
731 if (bitmap == NULL) {
732 rr->length = 0;
733 s->packet_length = 0; /* dump this record */
734 goto again; /* get another record */
735 }
736 #ifndef OPENSSL_NO_SCTP
737 /* Only do replay check if no SCTP bio */
738 if (!BIO_dgram_is_sctp(SSL_get_rbio(s))) {
739 #endif
740 /*
741 * Check whether this is a repeat, or aged record. Don't check if
742 * we're listening and this message is a ClientHello. They can look
743 * as if they're replayed, since they arrive from different
744 * connections and would be dropped unnecessarily.
745 */
746 if (!(s->d1->listen && rr->type == SSL3_RT_HANDSHAKE &&
747 s->packet_length > DTLS1_RT_HEADER_LENGTH &&
748 s->packet[DTLS1_RT_HEADER_LENGTH] == SSL3_MT_CLIENT_HELLO) &&
749 !dtls1_record_replay_check(s, bitmap)) {
750 rr->length = 0;
751 s->packet_length = 0; /* dump this record */
752 goto again; /* get another record */
753 }
754 #ifndef OPENSSL_NO_SCTP
755 }
756 #endif
757
758 /* just read a 0 length packet */
759 if (rr->length == 0)
760 goto again;
761
762 /*
763 * If this record is from the next epoch (either HM or ALERT), and a
764 * handshake is currently in progress, buffer it since it cannot be
765 * processed at this time. However, do not buffer anything while
766 * listening.
767 */
768 if (is_next_epoch) {
769 if ((SSL_in_init(s) || s->in_handshake) && !s->d1->listen) {
770 if (dtls1_buffer_record
771 (s, &(s->d1->unprocessed_rcds), rr->seq_num) < 0)
772 return -1;
773 }
774 rr->length = 0;
775 s->packet_length = 0;
776 goto again;
777 }
778
779 if (!dtls1_process_record(s, bitmap)) {
780 rr->length = 0;
781 s->packet_length = 0; /* dump this record */
782 goto again; /* get another record */
783 }
784
785 return (1);
786
787 }
788
789 /*-
790 * Return up to 'len' payload bytes received in 'type' records.
791 * 'type' is one of the following:
792 *
793 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
794 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
795 * - 0 (during a shutdown, no data has to be returned)
796 *
797 * If we don't have stored data to work from, read a SSL/TLS record first
798 * (possibly multiple records if we still don't have anything to return).
799 *
800 * This function must handle any surprises the peer may have for us, such as
801 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
802 * a surprise, but handled as if it were), or renegotiation requests.
803 * Also if record payloads contain fragments too small to process, we store
804 * them until there is enough for the respective protocol (the record protocol
805 * may use arbitrary fragmentation and even interleaving):
806 * Change cipher spec protocol
807 * just 1 byte needed, no need for keeping anything stored
808 * Alert protocol
809 * 2 bytes needed (AlertLevel, AlertDescription)
810 * Handshake protocol
811 * 4 bytes needed (HandshakeType, uint24 length) -- we just have
812 * to detect unexpected Client Hello and Hello Request messages
813 * here, anything else is handled by higher layers
814 * Application data protocol
815 * none of our business
816 */
dtls1_read_bytes(SSL * s,int type,unsigned char * buf,int len,int peek)817 int dtls1_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
818 {
819 int al, i, j, ret;
820 unsigned int n;
821 SSL3_RECORD *rr;
822 void (*cb) (const SSL *ssl, int type2, int val) = NULL;
823
824 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
825 if (!ssl3_setup_buffers(s))
826 return (-1);
827
828 /* XXX: check what the second '&& type' is about */
829 if ((type && (type != SSL3_RT_APPLICATION_DATA) &&
830 (type != SSL3_RT_HANDSHAKE) && type) ||
831 (peek && (type != SSL3_RT_APPLICATION_DATA))) {
832 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
833 return -1;
834 }
835
836 /*
837 * check whether there's a handshake message (client hello?) waiting
838 */
839 if ((ret = have_handshake_fragment(s, type, buf, len, peek)))
840 return ret;
841
842 /*
843 * Now s->d1->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE.
844 */
845
846 #ifndef OPENSSL_NO_SCTP
847 /*
848 * Continue handshake if it had to be interrupted to read app data with
849 * SCTP.
850 */
851 if ((!s->in_handshake && SSL_in_init(s)) ||
852 (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
853 (s->state == DTLS1_SCTP_ST_SR_READ_SOCK
854 || s->state == DTLS1_SCTP_ST_CR_READ_SOCK)
855 && s->s3->in_read_app_data != 2))
856 #else
857 if (!s->in_handshake && SSL_in_init(s))
858 #endif
859 {
860 /* type == SSL3_RT_APPLICATION_DATA */
861 i = s->handshake_func(s);
862 if (i < 0)
863 return (i);
864 if (i == 0) {
865 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
866 return (-1);
867 }
868 }
869
870 start:
871 s->rwstate = SSL_NOTHING;
872
873 /*-
874 * s->s3->rrec.type - is the type of record
875 * s->s3->rrec.data, - data
876 * s->s3->rrec.off, - offset into 'data' for next read
877 * s->s3->rrec.length, - number of bytes.
878 */
879 rr = &(s->s3->rrec);
880
881 /*
882 * We are not handshaking and have no data yet, so process data buffered
883 * during the last handshake in advance, if any.
884 */
885 if (s->state == SSL_ST_OK && rr->length == 0) {
886 pitem *item;
887 item = pqueue_pop(s->d1->buffered_app_data.q);
888 if (item) {
889 #ifndef OPENSSL_NO_SCTP
890 /* Restore bio_dgram_sctp_rcvinfo struct */
891 if (BIO_dgram_is_sctp(SSL_get_rbio(s))) {
892 DTLS1_RECORD_DATA *rdata = (DTLS1_RECORD_DATA *)item->data;
893 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_SET_RCVINFO,
894 sizeof(rdata->recordinfo), &rdata->recordinfo);
895 }
896 #endif
897
898 dtls1_copy_record(s, item);
899
900 OPENSSL_free(item->data);
901 pitem_free(item);
902 }
903 }
904
905 /* Check for timeout */
906 if (dtls1_handle_timeout(s) > 0)
907 goto start;
908
909 /* get new packet if necessary */
910 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY)) {
911 ret = dtls1_get_record(s);
912 if (ret <= 0) {
913 ret = dtls1_read_failed(s, ret);
914 /* anything other than a timeout is an error */
915 if (ret <= 0)
916 return (ret);
917 else
918 goto start;
919 }
920 }
921
922 if (s->d1->listen && rr->type != SSL3_RT_HANDSHAKE) {
923 rr->length = 0;
924 goto start;
925 }
926
927 /*
928 * Reset the count of consecutive warning alerts if we've got a non-empty
929 * record that isn't an alert.
930 */
931 if (rr->type != SSL3_RT_ALERT && rr->length != 0)
932 s->s3->alert_count = 0;
933
934 /* we now have a packet which can be read and processed */
935
936 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
937 * reset by ssl3_get_finished */
938 && (rr->type != SSL3_RT_HANDSHAKE)) {
939 /*
940 * We now have application data between CCS and Finished. Most likely
941 * the packets were reordered on their way, so buffer the application
942 * data for later processing rather than dropping the connection.
943 */
944 if (dtls1_buffer_record(s, &(s->d1->buffered_app_data), rr->seq_num) <
945 0) {
946 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
947 return -1;
948 }
949 rr->length = 0;
950 goto start;
951 }
952
953 /*
954 * If the other end has shut down, throw anything we read away (even in
955 * 'peek' mode)
956 */
957 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) {
958 rr->length = 0;
959 s->rwstate = SSL_NOTHING;
960 return (0);
961 }
962
963 if (type == rr->type) { /* SSL3_RT_APPLICATION_DATA or
964 * SSL3_RT_HANDSHAKE */
965 /*
966 * make sure that we are not getting application data when we are
967 * doing a handshake for the first time
968 */
969 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
970 (s->enc_read_ctx == NULL)) {
971 al = SSL_AD_UNEXPECTED_MESSAGE;
972 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_APP_DATA_IN_HANDSHAKE);
973 goto f_err;
974 }
975
976 if (len <= 0)
977 return (len);
978
979 if ((unsigned int)len > rr->length)
980 n = rr->length;
981 else
982 n = (unsigned int)len;
983
984 memcpy(buf, &(rr->data[rr->off]), n);
985 if (!peek) {
986 rr->length -= n;
987 rr->off += n;
988 if (rr->length == 0) {
989 s->rstate = SSL_ST_READ_HEADER;
990 rr->off = 0;
991 }
992 }
993 #ifndef OPENSSL_NO_SCTP
994 /*
995 * We were about to renegotiate but had to read belated application
996 * data first, so retry.
997 */
998 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
999 rr->type == SSL3_RT_APPLICATION_DATA &&
1000 (s->state == DTLS1_SCTP_ST_SR_READ_SOCK
1001 || s->state == DTLS1_SCTP_ST_CR_READ_SOCK)) {
1002 s->rwstate = SSL_READING;
1003 BIO_clear_retry_flags(SSL_get_rbio(s));
1004 BIO_set_retry_read(SSL_get_rbio(s));
1005 }
1006
1007 /*
1008 * We might had to delay a close_notify alert because of reordered
1009 * app data. If there was an alert and there is no message to read
1010 * anymore, finally set shutdown.
1011 */
1012 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
1013 s->d1->shutdown_received
1014 && !BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) {
1015 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1016 return (0);
1017 }
1018 #endif
1019 return (n);
1020 }
1021
1022 /*
1023 * If we get here, then type != rr->type; if we have a handshake message,
1024 * then it was unexpected (Hello Request or Client Hello).
1025 */
1026
1027 /*
1028 * In case of record types for which we have 'fragment' storage, fill
1029 * that so that we can process the data at a fixed place.
1030 */
1031 {
1032 unsigned int k, dest_maxlen = 0;
1033 unsigned char *dest = NULL;
1034 unsigned int *dest_len = NULL;
1035
1036 if (rr->type == SSL3_RT_HANDSHAKE) {
1037 dest_maxlen = sizeof s->d1->handshake_fragment;
1038 dest = s->d1->handshake_fragment;
1039 dest_len = &s->d1->handshake_fragment_len;
1040 } else if (rr->type == SSL3_RT_ALERT) {
1041 dest_maxlen = sizeof(s->d1->alert_fragment);
1042 dest = s->d1->alert_fragment;
1043 dest_len = &s->d1->alert_fragment_len;
1044 }
1045 #ifndef OPENSSL_NO_HEARTBEATS
1046 else if (rr->type == TLS1_RT_HEARTBEAT) {
1047 dtls1_process_heartbeat(s);
1048
1049 /* Exit and notify application to read again */
1050 rr->length = 0;
1051 s->rwstate = SSL_READING;
1052 BIO_clear_retry_flags(SSL_get_rbio(s));
1053 BIO_set_retry_read(SSL_get_rbio(s));
1054 return (-1);
1055 }
1056 #endif
1057 /* else it's a CCS message, or application data or wrong */
1058 else if (rr->type != SSL3_RT_CHANGE_CIPHER_SPEC) {
1059 /*
1060 * Application data while renegotiating is allowed. Try again
1061 * reading.
1062 */
1063 if (rr->type == SSL3_RT_APPLICATION_DATA) {
1064 BIO *bio;
1065 s->s3->in_read_app_data = 2;
1066 bio = SSL_get_rbio(s);
1067 s->rwstate = SSL_READING;
1068 BIO_clear_retry_flags(bio);
1069 BIO_set_retry_read(bio);
1070 return (-1);
1071 }
1072
1073 /* Not certain if this is the right error handling */
1074 al = SSL_AD_UNEXPECTED_MESSAGE;
1075 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
1076 goto f_err;
1077 }
1078
1079 if (dest_maxlen > 0) {
1080 /*
1081 * XDTLS: In a pathalogical case, the Client Hello may be
1082 * fragmented--don't always expect dest_maxlen bytes
1083 */
1084 if (rr->length < dest_maxlen) {
1085 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1086 /*
1087 * for normal alerts rr->length is 2, while
1088 * dest_maxlen is 7 if we were to handle this
1089 * non-existing alert...
1090 */
1091 FIX ME
1092 #endif
1093 s->rstate = SSL_ST_READ_HEADER;
1094 rr->length = 0;
1095 goto start;
1096 }
1097
1098 /* now move 'n' bytes: */
1099 for (k = 0; k < dest_maxlen; k++) {
1100 dest[k] = rr->data[rr->off++];
1101 rr->length--;
1102 }
1103 *dest_len = dest_maxlen;
1104 }
1105 }
1106
1107 /*-
1108 * s->d1->handshake_fragment_len == 12 iff rr->type == SSL3_RT_HANDSHAKE;
1109 * s->d1->alert_fragment_len == 7 iff rr->type == SSL3_RT_ALERT.
1110 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.)
1111 */
1112
1113 /* If we are a client, check for an incoming 'Hello Request': */
1114 if ((!s->server) &&
1115 (s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
1116 (s->d1->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1117 (s->session != NULL) && (s->session->cipher != NULL)) {
1118 s->d1->handshake_fragment_len = 0;
1119
1120 if ((s->d1->handshake_fragment[1] != 0) ||
1121 (s->d1->handshake_fragment[2] != 0) ||
1122 (s->d1->handshake_fragment[3] != 0)) {
1123 al = SSL_AD_DECODE_ERROR;
1124 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_BAD_HELLO_REQUEST);
1125 goto f_err;
1126 }
1127
1128 /*
1129 * no need to check sequence number on HELLO REQUEST messages
1130 */
1131
1132 if (s->msg_callback)
1133 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
1134 s->d1->handshake_fragment, 4, s,
1135 s->msg_callback_arg);
1136
1137 if (SSL_is_init_finished(s) &&
1138 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1139 !s->s3->renegotiate) {
1140 s->d1->handshake_read_seq++;
1141 s->new_session = 1;
1142 ssl3_renegotiate(s);
1143 if (ssl3_renegotiate_check(s)) {
1144 i = s->handshake_func(s);
1145 if (i < 0)
1146 return (i);
1147 if (i == 0) {
1148 SSLerr(SSL_F_DTLS1_READ_BYTES,
1149 SSL_R_SSL_HANDSHAKE_FAILURE);
1150 return (-1);
1151 }
1152
1153 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
1154 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */
1155 BIO *bio;
1156 /*
1157 * In the case where we try to read application data,
1158 * but we trigger an SSL handshake, we return -1 with
1159 * the retry option set. Otherwise renegotiation may
1160 * cause nasty problems in the blocking world
1161 */
1162 s->rwstate = SSL_READING;
1163 bio = SSL_get_rbio(s);
1164 BIO_clear_retry_flags(bio);
1165 BIO_set_retry_read(bio);
1166 return (-1);
1167 }
1168 }
1169 }
1170 }
1171 /*
1172 * we either finished a handshake or ignored the request, now try
1173 * again to obtain the (application) data we were asked for
1174 */
1175 goto start;
1176 }
1177
1178 if (s->d1->alert_fragment_len >= DTLS1_AL_HEADER_LENGTH) {
1179 int alert_level = s->d1->alert_fragment[0];
1180 int alert_descr = s->d1->alert_fragment[1];
1181
1182 s->d1->alert_fragment_len = 0;
1183
1184 if (s->msg_callback)
1185 s->msg_callback(0, s->version, SSL3_RT_ALERT,
1186 s->d1->alert_fragment, 2, s, s->msg_callback_arg);
1187
1188 if (s->info_callback != NULL)
1189 cb = s->info_callback;
1190 else if (s->ctx->info_callback != NULL)
1191 cb = s->ctx->info_callback;
1192
1193 if (cb != NULL) {
1194 j = (alert_level << 8) | alert_descr;
1195 cb(s, SSL_CB_READ_ALERT, j);
1196 }
1197
1198 if (alert_level == SSL3_AL_WARNING) {
1199 s->s3->warn_alert = alert_descr;
1200
1201 s->s3->alert_count++;
1202 if (s->s3->alert_count == MAX_WARN_ALERT_COUNT) {
1203 al = SSL_AD_UNEXPECTED_MESSAGE;
1204 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_TOO_MANY_WARN_ALERTS);
1205 goto f_err;
1206 }
1207
1208 if (alert_descr == SSL_AD_CLOSE_NOTIFY) {
1209 #ifndef OPENSSL_NO_SCTP
1210 /*
1211 * With SCTP and streams the socket may deliver app data
1212 * after a close_notify alert. We have to check this first so
1213 * that nothing gets discarded.
1214 */
1215 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
1216 BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) {
1217 s->d1->shutdown_received = 1;
1218 s->rwstate = SSL_READING;
1219 BIO_clear_retry_flags(SSL_get_rbio(s));
1220 BIO_set_retry_read(SSL_get_rbio(s));
1221 return -1;
1222 }
1223 #endif
1224 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1225 return (0);
1226 }
1227 #if 0
1228 /* XXX: this is a possible improvement in the future */
1229 /* now check if it's a missing record */
1230 if (alert_descr == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE) {
1231 unsigned short seq;
1232 unsigned int frag_off;
1233 unsigned char *p = &(s->d1->alert_fragment[2]);
1234
1235 n2s(p, seq);
1236 n2l3(p, frag_off);
1237
1238 dtls1_retransmit_message(s,
1239 dtls1_get_queue_priority
1240 (frag->msg_header.seq, 0), frag_off,
1241 &found);
1242 if (!found && SSL_in_init(s)) {
1243 /*
1244 * fprintf( stderr,"in init = %d\n", SSL_in_init(s));
1245 */
1246 /*
1247 * requested a message not yet sent, send an alert
1248 * ourselves
1249 */
1250 ssl3_send_alert(s, SSL3_AL_WARNING,
1251 DTLS1_AD_MISSING_HANDSHAKE_MESSAGE);
1252 }
1253 }
1254 #endif
1255 } else if (alert_level == SSL3_AL_FATAL) {
1256 char tmp[16];
1257
1258 s->rwstate = SSL_NOTHING;
1259 s->s3->fatal_alert = alert_descr;
1260 SSLerr(SSL_F_DTLS1_READ_BYTES,
1261 SSL_AD_REASON_OFFSET + alert_descr);
1262 BIO_snprintf(tmp, sizeof tmp, "%d", alert_descr);
1263 ERR_add_error_data(2, "SSL alert number ", tmp);
1264 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1265 SSL_CTX_remove_session(s->ctx, s->session);
1266 return (0);
1267 } else {
1268 al = SSL_AD_ILLEGAL_PARAMETER;
1269 SSLerr(SSL_F_DTLS1_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
1277 * shutdown */
1278 s->rwstate = SSL_NOTHING;
1279 rr->length = 0;
1280 return (0);
1281 }
1282
1283 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) {
1284 struct ccs_header_st ccs_hdr;
1285 unsigned int ccs_hdr_len = DTLS1_CCS_HEADER_LENGTH;
1286
1287 dtls1_get_ccs_header(rr->data, &ccs_hdr);
1288
1289 if (s->version == DTLS1_BAD_VER)
1290 ccs_hdr_len = 3;
1291
1292 /*
1293 * 'Change Cipher Spec' is just a single byte, so we know exactly
1294 * what the record payload has to look like
1295 */
1296 /* XDTLS: check that epoch is consistent */
1297 if ((rr->length != ccs_hdr_len) ||
1298 (rr->off != 0) || (rr->data[0] != SSL3_MT_CCS)) {
1299 i = SSL_AD_ILLEGAL_PARAMETER;
1300 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_BAD_CHANGE_CIPHER_SPEC);
1301 goto err;
1302 }
1303
1304 rr->length = 0;
1305
1306 if (s->msg_callback)
1307 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC,
1308 rr->data, 1, s, s->msg_callback_arg);
1309
1310 /*
1311 * We can't process a CCS now, because previous handshake messages
1312 * are still missing, so just drop it.
1313 */
1314 if (!s->d1->change_cipher_spec_ok) {
1315 goto start;
1316 }
1317
1318 s->d1->change_cipher_spec_ok = 0;
1319
1320 s->s3->change_cipher_spec = 1;
1321 if (!ssl3_do_change_cipher_spec(s))
1322 goto err;
1323
1324 /* do this whenever CCS is processed */
1325 dtls1_reset_seq_numbers(s, SSL3_CC_READ);
1326
1327 if (s->version == DTLS1_BAD_VER)
1328 s->d1->handshake_read_seq++;
1329
1330 #ifndef OPENSSL_NO_SCTP
1331 /*
1332 * Remember that a CCS has been received, so that an old key of
1333 * SCTP-Auth can be deleted when a CCS is sent. Will be ignored if no
1334 * SCTP is used
1335 */
1336 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD, 1, NULL);
1337 #endif
1338
1339 goto start;
1340 }
1341
1342 /*
1343 * Unexpected handshake message (Client Hello, or protocol violation)
1344 */
1345 if ((s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
1346 !s->in_handshake) {
1347 struct hm_header_st msg_hdr;
1348
1349 /* this may just be a stale retransmit */
1350 dtls1_get_message_header(rr->data, &msg_hdr);
1351 if (rr->epoch != s->d1->r_epoch) {
1352 rr->length = 0;
1353 goto start;
1354 }
1355
1356 /*
1357 * If we are server, we may have a repeated FINISHED of the client
1358 * here, then retransmit our CCS and FINISHED.
1359 */
1360 if (msg_hdr.type == SSL3_MT_FINISHED) {
1361 if (dtls1_check_timeout_num(s) < 0)
1362 return -1;
1363
1364 dtls1_retransmit_buffered_messages(s);
1365 rr->length = 0;
1366 goto start;
1367 }
1368
1369 if (((s->state & SSL_ST_MASK) == SSL_ST_OK) &&
1370 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) {
1371 #if 0 /* worked only because C operator preferences
1372 * are not as expected (and because this is
1373 * not really needed for clients except for
1374 * detecting protocol violations): */
1375 s->state = SSL_ST_BEFORE | (s->server)
1376 ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1377 #else
1378 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1379 #endif
1380 s->renegotiate = 1;
1381 s->new_session = 1;
1382 }
1383 i = s->handshake_func(s);
1384 if (i < 0)
1385 return (i);
1386 if (i == 0) {
1387 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
1388 return (-1);
1389 }
1390
1391 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
1392 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */
1393 BIO *bio;
1394 /*
1395 * In the case where we try to read application data, but we
1396 * trigger an SSL handshake, we return -1 with the retry
1397 * option set. Otherwise renegotiation may cause nasty
1398 * problems in the blocking world
1399 */
1400 s->rwstate = SSL_READING;
1401 bio = SSL_get_rbio(s);
1402 BIO_clear_retry_flags(bio);
1403 BIO_set_retry_read(bio);
1404 return (-1);
1405 }
1406 }
1407 goto start;
1408 }
1409
1410 switch (rr->type) {
1411 default:
1412 #ifndef OPENSSL_NO_TLS
1413 /* TLS just ignores unknown message types */
1414 if (s->version == TLS1_VERSION) {
1415 rr->length = 0;
1416 goto start;
1417 }
1418 #endif
1419 al = SSL_AD_UNEXPECTED_MESSAGE;
1420 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
1421 goto f_err;
1422 case SSL3_RT_CHANGE_CIPHER_SPEC:
1423 case SSL3_RT_ALERT:
1424 case SSL3_RT_HANDSHAKE:
1425 /*
1426 * we already handled all of these, with the possible exception of
1427 * SSL3_RT_HANDSHAKE when s->in_handshake is set, but that should not
1428 * happen when type != rr->type
1429 */
1430 al = SSL_AD_UNEXPECTED_MESSAGE;
1431 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
1432 goto f_err;
1433 case SSL3_RT_APPLICATION_DATA:
1434 /*
1435 * At this point, we were expecting handshake data, but have
1436 * application data. If the library was running inside ssl3_read()
1437 * (i.e. in_read_app_data is set) and it makes sense to read
1438 * application data at this point (session renegotiation not yet
1439 * started), we will indulge it.
1440 */
1441 if (s->s3->in_read_app_data &&
1442 (s->s3->total_renegotiations != 0) &&
1443 (((s->state & SSL_ST_CONNECT) &&
1444 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1445 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1446 ) || ((s->state & SSL_ST_ACCEPT) &&
1447 (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1448 (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1449 )
1450 )) {
1451 s->s3->in_read_app_data = 2;
1452 return (-1);
1453 } else {
1454 al = SSL_AD_UNEXPECTED_MESSAGE;
1455 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
1456 goto f_err;
1457 }
1458 }
1459 /* not reached */
1460
1461 f_err:
1462 ssl3_send_alert(s, SSL3_AL_FATAL, al);
1463 err:
1464 return (-1);
1465 }
1466
dtls1_write_app_data_bytes(SSL * s,int type,const void * buf_,int len)1467 int dtls1_write_app_data_bytes(SSL *s, int type, const void *buf_, int len)
1468 {
1469 int i;
1470
1471 #ifndef OPENSSL_NO_SCTP
1472 /*
1473 * Check if we have to continue an interrupted handshake for reading
1474 * belated app data with SCTP.
1475 */
1476 if ((SSL_in_init(s) && !s->in_handshake) ||
1477 (BIO_dgram_is_sctp(SSL_get_wbio(s)) &&
1478 (s->state == DTLS1_SCTP_ST_SR_READ_SOCK
1479 || s->state == DTLS1_SCTP_ST_CR_READ_SOCK)))
1480 #else
1481 if (SSL_in_init(s) && !s->in_handshake)
1482 #endif
1483 {
1484 i = s->handshake_func(s);
1485 if (i < 0)
1486 return (i);
1487 if (i == 0) {
1488 SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES,
1489 SSL_R_SSL_HANDSHAKE_FAILURE);
1490 return -1;
1491 }
1492 }
1493
1494 if (len > SSL3_RT_MAX_PLAIN_LENGTH) {
1495 SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES, SSL_R_DTLS_MESSAGE_TOO_BIG);
1496 return -1;
1497 }
1498
1499 i = dtls1_write_bytes(s, type, buf_, len);
1500 return i;
1501 }
1502
1503 /*
1504 * this only happens when a client hello is received and a handshake
1505 * is started.
1506 */
1507 static int
have_handshake_fragment(SSL * s,int type,unsigned char * buf,int len,int peek)1508 have_handshake_fragment(SSL *s, int type, unsigned char *buf,
1509 int len, int peek)
1510 {
1511
1512 if ((type == SSL3_RT_HANDSHAKE) && (s->d1->handshake_fragment_len > 0))
1513 /* (partially) satisfy request from storage */
1514 {
1515 unsigned char *src = s->d1->handshake_fragment;
1516 unsigned char *dst = buf;
1517 unsigned int k, n;
1518
1519 /* peek == 0 */
1520 n = 0;
1521 while ((len > 0) && (s->d1->handshake_fragment_len > 0)) {
1522 *dst++ = *src++;
1523 len--;
1524 s->d1->handshake_fragment_len--;
1525 n++;
1526 }
1527 /* move any remaining fragment bytes: */
1528 for (k = 0; k < s->d1->handshake_fragment_len; k++)
1529 s->d1->handshake_fragment[k] = *src++;
1530 return n;
1531 }
1532
1533 return 0;
1534 }
1535
1536 /*
1537 * Call this to write data in records of type 'type' It will return <= 0 if
1538 * not all data has been sent or non-blocking IO.
1539 */
dtls1_write_bytes(SSL * s,int type,const void * buf,int len)1540 int dtls1_write_bytes(SSL *s, int type, const void *buf, int len)
1541 {
1542 int i;
1543
1544 OPENSSL_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH);
1545 s->rwstate = SSL_NOTHING;
1546 i = do_dtls1_write(s, type, buf, len, 0);
1547 return i;
1548 }
1549
do_dtls1_write(SSL * s,int type,const unsigned char * buf,unsigned int len,int create_empty_fragment)1550 int do_dtls1_write(SSL *s, int type, const unsigned char *buf,
1551 unsigned int len, int create_empty_fragment)
1552 {
1553 unsigned char *p, *pseq;
1554 int i, mac_size, clear = 0;
1555 int prefix_len = 0;
1556 SSL3_RECORD *wr;
1557 SSL3_BUFFER *wb;
1558 SSL_SESSION *sess;
1559 int bs;
1560
1561 /*
1562 * first check if there is a SSL3_BUFFER still being written out. This
1563 * will happen with non blocking IO
1564 */
1565 if (s->s3->wbuf.left != 0) {
1566 OPENSSL_assert(0); /* XDTLS: want to see if we ever get here */
1567 return (ssl3_write_pending(s, type, buf, len));
1568 }
1569
1570 /* If we have an alert to send, lets send it */
1571 if (s->s3->alert_dispatch) {
1572 i = s->method->ssl_dispatch_alert(s);
1573 if (i <= 0)
1574 return (i);
1575 /* if it went, fall through and send more stuff */
1576 }
1577
1578 if (len == 0 && !create_empty_fragment)
1579 return 0;
1580
1581 wr = &(s->s3->wrec);
1582 wb = &(s->s3->wbuf);
1583 sess = s->session;
1584
1585 if ((sess == NULL) ||
1586 (s->enc_write_ctx == NULL) || (EVP_MD_CTX_md(s->write_hash) == NULL))
1587 clear = 1;
1588
1589 if (clear)
1590 mac_size = 0;
1591 else {
1592 mac_size = EVP_MD_CTX_size(s->write_hash);
1593 if (mac_size < 0)
1594 goto err;
1595 }
1596
1597 /* DTLS implements explicit IV, so no need for empty fragments */
1598 #if 0
1599 /*
1600 * 'create_empty_fragment' is true only when this function calls itself
1601 */
1602 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done
1603 && SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
1604 {
1605 /*
1606 * countermeasure against known-IV weakness in CBC ciphersuites (see
1607 * http://www.openssl.org/~bodo/tls-cbc.txt)
1608 */
1609
1610 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA) {
1611 /*
1612 * recursive function call with 'create_empty_fragment' set; this
1613 * prepares and buffers the data for an empty fragment (these
1614 * 'prefix_len' bytes are sent out later together with the actual
1615 * payload)
1616 */
1617 prefix_len = s->method->do_ssl_write(s, type, buf, 0, 1);
1618 if (prefix_len <= 0)
1619 goto err;
1620
1621 if (s->s3->wbuf.len <
1622 (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE) {
1623 /* insufficient space */
1624 SSLerr(SSL_F_DO_DTLS1_WRITE, ERR_R_INTERNAL_ERROR);
1625 goto err;
1626 }
1627 }
1628
1629 s->s3->empty_fragment_done = 1;
1630 }
1631 #endif
1632 p = wb->buf + prefix_len;
1633
1634 /* write the header */
1635
1636 *(p++) = type & 0xff;
1637 wr->type = type;
1638
1639 *(p++) = (s->version >> 8);
1640 *(p++) = s->version & 0xff;
1641
1642 /* field where we are to write out packet epoch, seq num and len */
1643 pseq = p;
1644 p += 10;
1645
1646 /* lets setup the record stuff. */
1647
1648 /*
1649 * Make space for the explicit IV in case of CBC. (this is a bit of a
1650 * boundary violation, but what the heck).
1651 */
1652 if (s->enc_write_ctx &&
1653 (EVP_CIPHER_mode(s->enc_write_ctx->cipher) & EVP_CIPH_CBC_MODE))
1654 bs = EVP_CIPHER_block_size(s->enc_write_ctx->cipher);
1655 else
1656 bs = 0;
1657
1658 wr->data = p + bs; /* make room for IV in case of CBC */
1659 wr->length = (int)len;
1660 wr->input = (unsigned char *)buf;
1661
1662 /*
1663 * we now 'read' from wr->input, wr->length bytes into wr->data
1664 */
1665
1666 /* first we compress */
1667 if (s->compress != NULL) {
1668 if (!ssl3_do_compress(s)) {
1669 SSLerr(SSL_F_DO_DTLS1_WRITE, SSL_R_COMPRESSION_FAILURE);
1670 goto err;
1671 }
1672 } else {
1673 memcpy(wr->data, wr->input, wr->length);
1674 wr->input = wr->data;
1675 }
1676
1677 /*
1678 * we should still have the output to wr->data and the input from
1679 * wr->input. Length should be wr->length. wr->data still points in the
1680 * wb->buf
1681 */
1682
1683 if (mac_size != 0) {
1684 if (s->method->ssl3_enc->mac(s, &(p[wr->length + bs]), 1) < 0)
1685 goto err;
1686 wr->length += mac_size;
1687 }
1688
1689 /* this is true regardless of mac size */
1690 wr->input = p;
1691 wr->data = p;
1692
1693 /* ssl3_enc can only have an error on read */
1694 if (bs) { /* bs != 0 in case of CBC */
1695 if (RAND_bytes(p, bs) <= 0)
1696 goto err;
1697 /*
1698 * master IV and last CBC residue stand for the rest of randomness
1699 */
1700 wr->length += bs;
1701 }
1702
1703 if (s->method->ssl3_enc->enc(s, 1) < 1)
1704 goto err;
1705
1706 /* record length after mac and block padding */
1707 /*
1708 * if (type == SSL3_RT_APPLICATION_DATA || (type == SSL3_RT_ALERT && !
1709 * SSL_in_init(s)))
1710 */
1711
1712 /* there's only one epoch between handshake and app data */
1713
1714 s2n(s->d1->w_epoch, pseq);
1715
1716 /* XDTLS: ?? */
1717 /*
1718 * else s2n(s->d1->handshake_epoch, pseq);
1719 */
1720
1721 memcpy(pseq, &(s->s3->write_sequence[2]), 6);
1722 pseq += 6;
1723 s2n(wr->length, pseq);
1724
1725 /*
1726 * we should now have wr->data pointing to the encrypted data, which is
1727 * wr->length long
1728 */
1729 wr->type = type; /* not needed but helps for debugging */
1730 wr->length += DTLS1_RT_HEADER_LENGTH;
1731
1732 #if 0 /* this is now done at the message layer */
1733 /* buffer the record, making it easy to handle retransmits */
1734 if (type == SSL3_RT_HANDSHAKE || type == SSL3_RT_CHANGE_CIPHER_SPEC)
1735 dtls1_buffer_record(s, wr->data, wr->length,
1736 *((PQ_64BIT *) & (s->s3->write_sequence[0])));
1737 #endif
1738
1739 ssl3_record_sequence_update(&(s->s3->write_sequence[0]));
1740
1741 if (create_empty_fragment) {
1742 /*
1743 * we are in a recursive call; just return the length, don't write
1744 * out anything here
1745 */
1746 return wr->length;
1747 }
1748
1749 /* now let's set up wb */
1750 wb->left = prefix_len + wr->length;
1751 wb->offset = 0;
1752
1753 /*
1754 * memorize arguments so that ssl3_write_pending can detect bad write
1755 * retries later
1756 */
1757 s->s3->wpend_tot = len;
1758 s->s3->wpend_buf = buf;
1759 s->s3->wpend_type = type;
1760 s->s3->wpend_ret = len;
1761
1762 /* we now just need to write the buffer */
1763 return ssl3_write_pending(s, type, buf, len);
1764 err:
1765 return -1;
1766 }
1767
dtls1_record_replay_check(SSL * s,DTLS1_BITMAP * bitmap)1768 static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap)
1769 {
1770 int cmp;
1771 unsigned int shift;
1772 const unsigned char *seq = s->s3->read_sequence;
1773
1774 cmp = satsub64be(seq, bitmap->max_seq_num);
1775 if (cmp > 0) {
1776 memcpy(s->s3->rrec.seq_num, seq, 8);
1777 return 1; /* this record in new */
1778 }
1779 shift = -cmp;
1780 if (shift >= sizeof(bitmap->map) * 8)
1781 return 0; /* stale, outside the window */
1782 else if (bitmap->map & (1UL << shift))
1783 return 0; /* record previously received */
1784
1785 memcpy(s->s3->rrec.seq_num, seq, 8);
1786 return 1;
1787 }
1788
dtls1_record_bitmap_update(SSL * s,DTLS1_BITMAP * bitmap)1789 static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap)
1790 {
1791 int cmp;
1792 unsigned int shift;
1793 const unsigned char *seq = s->s3->read_sequence;
1794
1795 cmp = satsub64be(seq, bitmap->max_seq_num);
1796 if (cmp > 0) {
1797 shift = cmp;
1798 if (shift < sizeof(bitmap->map) * 8)
1799 bitmap->map <<= shift, bitmap->map |= 1UL;
1800 else
1801 bitmap->map = 1UL;
1802 memcpy(bitmap->max_seq_num, seq, 8);
1803 } else {
1804 shift = -cmp;
1805 if (shift < sizeof(bitmap->map) * 8)
1806 bitmap->map |= 1UL << shift;
1807 }
1808 }
1809
dtls1_dispatch_alert(SSL * s)1810 int dtls1_dispatch_alert(SSL *s)
1811 {
1812 int i, j;
1813 void (*cb) (const SSL *ssl, int type, int val) = NULL;
1814 unsigned char buf[DTLS1_AL_HEADER_LENGTH];
1815 unsigned char *ptr = &buf[0];
1816
1817 s->s3->alert_dispatch = 0;
1818
1819 memset(buf, 0x00, sizeof(buf));
1820 *ptr++ = s->s3->send_alert[0];
1821 *ptr++ = s->s3->send_alert[1];
1822
1823 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1824 if (s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE) {
1825 s2n(s->d1->handshake_read_seq, ptr);
1826 # if 0
1827 if (s->d1->r_msg_hdr.frag_off == 0)
1828 /*
1829 * waiting for a new msg
1830 */
1831 else
1832 s2n(s->d1->r_msg_hdr.seq, ptr); /* partial msg read */
1833 # endif
1834
1835 # if 0
1836 fprintf(stderr,
1837 "s->d1->handshake_read_seq = %d, s->d1->r_msg_hdr.seq = %d\n",
1838 s->d1->handshake_read_seq, s->d1->r_msg_hdr.seq);
1839 # endif
1840 l2n3(s->d1->r_msg_hdr.frag_off, ptr);
1841 }
1842 #endif
1843
1844 i = do_dtls1_write(s, SSL3_RT_ALERT, &buf[0], sizeof(buf), 0);
1845 if (i <= 0) {
1846 s->s3->alert_dispatch = 1;
1847 /* fprintf( stderr, "not done with alert\n" ); */
1848 } else {
1849 if (s->s3->send_alert[0] == SSL3_AL_FATAL
1850 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1851 || s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1852 #endif
1853 )
1854 (void)BIO_flush(s->wbio);
1855
1856 if (s->msg_callback)
1857 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert,
1858 2, s, s->msg_callback_arg);
1859
1860 if (s->info_callback != NULL)
1861 cb = s->info_callback;
1862 else if (s->ctx->info_callback != NULL)
1863 cb = s->ctx->info_callback;
1864
1865 if (cb != NULL) {
1866 j = (s->s3->send_alert[0] << 8) | s->s3->send_alert[1];
1867 cb(s, SSL_CB_WRITE_ALERT, j);
1868 }
1869 }
1870 return (i);
1871 }
1872
dtls1_get_bitmap(SSL * s,SSL3_RECORD * rr,unsigned int * is_next_epoch)1873 static DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr,
1874 unsigned int *is_next_epoch)
1875 {
1876
1877 *is_next_epoch = 0;
1878
1879 /* In current epoch, accept HM, CCS, DATA, & ALERT */
1880 if (rr->epoch == s->d1->r_epoch)
1881 return &s->d1->bitmap;
1882
1883 /*
1884 * Only HM and ALERT messages can be from the next epoch and only if we
1885 * have already processed all of the unprocessed records from the last
1886 * epoch
1887 */
1888 else if (rr->epoch == (unsigned long)(s->d1->r_epoch + 1) &&
1889 s->d1->unprocessed_rcds.epoch != s->d1->r_epoch &&
1890 (rr->type == SSL3_RT_HANDSHAKE || rr->type == SSL3_RT_ALERT)) {
1891 *is_next_epoch = 1;
1892 return &s->d1->next_bitmap;
1893 }
1894
1895 return NULL;
1896 }
1897
1898 #if 0
1899 static int
1900 dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr,
1901 unsigned short *priority, unsigned long *offset)
1902 {
1903
1904 /* alerts are passed up immediately */
1905 if (rr->type == SSL3_RT_APPLICATION_DATA || rr->type == SSL3_RT_ALERT)
1906 return 0;
1907
1908 /*
1909 * Only need to buffer if a handshake is underway. (this implies that
1910 * Hello Request and Client Hello are passed up immediately)
1911 */
1912 if (SSL_in_init(s)) {
1913 unsigned char *data = rr->data;
1914 /* need to extract the HM/CCS sequence number here */
1915 if (rr->type == SSL3_RT_HANDSHAKE ||
1916 rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) {
1917 unsigned short seq_num;
1918 struct hm_header_st msg_hdr;
1919 struct ccs_header_st ccs_hdr;
1920
1921 if (rr->type == SSL3_RT_HANDSHAKE) {
1922 dtls1_get_message_header(data, &msg_hdr);
1923 seq_num = msg_hdr.seq;
1924 *offset = msg_hdr.frag_off;
1925 } else {
1926 dtls1_get_ccs_header(data, &ccs_hdr);
1927 seq_num = ccs_hdr.seq;
1928 *offset = 0;
1929 }
1930
1931 /*
1932 * this is either a record we're waiting for, or a retransmit of
1933 * something we happened to previously receive (higher layers
1934 * will drop the repeat silently
1935 */
1936 if (seq_num < s->d1->handshake_read_seq)
1937 return 0;
1938 if (rr->type == SSL3_RT_HANDSHAKE &&
1939 seq_num == s->d1->handshake_read_seq &&
1940 msg_hdr.frag_off < s->d1->r_msg_hdr.frag_off)
1941 return 0;
1942 else if (seq_num == s->d1->handshake_read_seq &&
1943 (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC ||
1944 msg_hdr.frag_off == s->d1->r_msg_hdr.frag_off))
1945 return 0;
1946 else {
1947 *priority = seq_num;
1948 return 1;
1949 }
1950 } else /* unknown record type */
1951 return 0;
1952 }
1953
1954 return 0;
1955 }
1956 #endif
1957
dtls1_reset_seq_numbers(SSL * s,int rw)1958 void dtls1_reset_seq_numbers(SSL *s, int rw)
1959 {
1960 unsigned char *seq;
1961 unsigned int seq_bytes = sizeof(s->s3->read_sequence);
1962
1963 if (rw & SSL3_CC_READ) {
1964 seq = s->s3->read_sequence;
1965 s->d1->r_epoch++;
1966 memcpy(&(s->d1->bitmap), &(s->d1->next_bitmap), sizeof(DTLS1_BITMAP));
1967 memset(&(s->d1->next_bitmap), 0x00, sizeof(DTLS1_BITMAP));
1968
1969 /*
1970 * We must not use any buffered messages received from the previous
1971 * epoch
1972 */
1973 dtls1_clear_received_buffer(s);
1974 } else {
1975 seq = s->s3->write_sequence;
1976 memcpy(s->d1->last_write_sequence, seq,
1977 sizeof(s->s3->write_sequence));
1978 s->d1->w_epoch++;
1979 }
1980
1981 memset(seq, 0x00, seq_bytes);
1982 }
1983