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Lots of Win32 fixes for DTLS.
[thirdparty/openssl.git] / ssl / d1_pkt.c
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
124 static int have_handshake_fragment(SSL *s, int type, unsigned char *buf,
125 int len, int peek);
126 static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap,
127 BN_ULLONG *seq_num);
128 static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap);
129 static DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr,
130 unsigned int *is_next_epoch);
131 #if 0
132 static int dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr,
133 unsigned short *priority, unsigned long *offset);
134 #endif
135 static int dtls1_buffer_record(SSL *s, record_pqueue *q,
136 BN_ULLONG priority);
137 static int dtls1_process_record(SSL *s);
138 static BN_ULLONG bytes_to_long_long(unsigned char *bytes);
139 static void long_long_to_bytes(BN_ULLONG num, unsigned char *bytes);
140 static void dtls1_clear_timeouts(SSL *s);
141
142
143 /* copy buffered record into SSL structure */
144 static int
145 dtls1_copy_record(SSL *s, pitem *item)
146 {
147 DTLS1_RECORD_DATA *rdata;
148
149 rdata = (DTLS1_RECORD_DATA *)item->data;
150
151 if (s->s3->rbuf.buf != NULL)
152 OPENSSL_free(s->s3->rbuf.buf);
153
154 s->packet = rdata->packet;
155 s->packet_length = rdata->packet_length;
156 memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER));
157 memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD));
158
159 return(1);
160 }
161
162
163 static int
164 dtls1_buffer_record(SSL *s, record_pqueue *queue, BN_ULLONG priority)
165 {
166 DTLS1_RECORD_DATA *rdata;
167 pitem *item;
168
169 rdata = OPENSSL_malloc(sizeof(DTLS1_RECORD_DATA));
170 item = pitem_new(priority, rdata);
171 if (rdata == NULL || item == NULL)
172 {
173 if (rdata != NULL) OPENSSL_free(rdata);
174 if (item != NULL) pitem_free(item);
175
176 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
177 return(0);
178 }
179
180 rdata->packet = s->packet;
181 rdata->packet_length = s->packet_length;
182 memcpy(&(rdata->rbuf), &(s->s3->rbuf), sizeof(SSL3_BUFFER));
183 memcpy(&(rdata->rrec), &(s->s3->rrec), sizeof(SSL3_RECORD));
184
185 item->data = rdata;
186
187 /* insert should not fail, since duplicates are dropped */
188 if (pqueue_insert(queue->q, item) == NULL)
189 {
190 OPENSSL_free(rdata);
191 pitem_free(item);
192 return(0);
193 }
194
195 s->packet = NULL;
196 s->packet_length = 0;
197 memset(&(s->s3->rbuf), 0, sizeof(SSL3_BUFFER));
198 memset(&(s->s3->rrec), 0, sizeof(SSL3_RECORD));
199
200 ssl3_setup_buffers(s);
201
202 return(1);
203 }
204
205
206 static int
207 dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue)
208 {
209 pitem *item;
210
211 item = pqueue_pop(queue->q);
212 if (item)
213 {
214 dtls1_copy_record(s, item);
215
216 OPENSSL_free(item->data);
217 pitem_free(item);
218
219 return(1);
220 }
221
222 return(0);
223 }
224
225
226 /* retrieve a buffered record that belongs to the new epoch, i.e., not processed
227 * yet */
228 #define dtls1_get_unprocessed_record(s) \
229 dtls1_retrieve_buffered_record((s), \
230 &((s)->d1->unprocessed_rcds))
231
232 /* retrieve a buffered record that belongs to the current epoch, ie, processed */
233 #define dtls1_get_processed_record(s) \
234 dtls1_retrieve_buffered_record((s), \
235 &((s)->d1->processed_rcds))
236
237 static int
238 dtls1_process_buffered_records(SSL *s)
239 {
240 pitem *item;
241
242 item = pqueue_peek(s->d1->unprocessed_rcds.q);
243 if (item)
244 {
245 DTLS1_RECORD_DATA *rdata;
246 rdata = (DTLS1_RECORD_DATA *)item->data;
247
248 /* Check if epoch is current. */
249 if (s->d1->unprocessed_rcds.epoch != s->d1->r_epoch)
250 return(1); /* Nothing to do. */
251
252 /* Process all the records. */
253 while (pqueue_peek(s->d1->unprocessed_rcds.q))
254 {
255 dtls1_get_unprocessed_record(s);
256 if ( ! dtls1_process_record(s))
257 return(0);
258 dtls1_buffer_record(s, &(s->d1->processed_rcds),
259 s->s3->rrec.seq_num);
260 }
261 }
262
263 /* sync epoch numbers once all the unprocessed records
264 * have been processed */
265 s->d1->processed_rcds.epoch = s->d1->r_epoch;
266 s->d1->unprocessed_rcds.epoch = s->d1->r_epoch + 1;
267
268 return(1);
269 }
270
271
272 #if 0
273
274 static int
275 dtls1_get_buffered_record(SSL *s)
276 {
277 pitem *item;
278 BN_ULLONG priority =
279 (((BN_ULLONG)s->d1->handshake_read_seq) << 32) |
280 ((BN_ULLONG)s->d1->r_msg_hdr.frag_off);
281
282 if ( ! SSL_in_init(s)) /* if we're not (re)negotiating,
283 nothing buffered */
284 return 0;
285
286
287 item = pqueue_peek(s->d1->rcvd_records);
288 if (item && item->priority == priority)
289 {
290 /* Check if we've received the record of interest. It must be
291 * a handshake record, since data records as passed up without
292 * buffering */
293 DTLS1_RECORD_DATA *rdata;
294 item = pqueue_pop(s->d1->rcvd_records);
295 rdata = (DTLS1_RECORD_DATA *)item->data;
296
297 if (s->s3->rbuf.buf != NULL)
298 OPENSSL_free(s->s3->rbuf.buf);
299
300 s->packet = rdata->packet;
301 s->packet_length = rdata->packet_length;
302 memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER));
303 memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD));
304
305 OPENSSL_free(item->data);
306 pitem_free(item);
307
308 /* s->d1->next_expected_seq_num++; */
309 return(1);
310 }
311
312 return 0;
313 }
314
315 #endif
316
317 static int
318 dtls1_process_record(SSL *s)
319 {
320 int i,al;
321 int clear=0;
322 int enc_err;
323 SSL_SESSION *sess;
324 SSL3_RECORD *rr;
325 unsigned int mac_size;
326 unsigned char md[EVP_MAX_MD_SIZE];
327
328
329 rr= &(s->s3->rrec);
330 sess = s->session;
331
332 /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
333 * and we have that many bytes in s->packet
334 */
335 rr->input= &(s->packet[DTLS1_RT_HEADER_LENGTH]);
336
337 /* ok, we can now read from 's->packet' data into 'rr'
338 * rr->input points at rr->length bytes, which
339 * need to be copied into rr->data by either
340 * the decryption or by the decompression
341 * When the data is 'copied' into the rr->data buffer,
342 * rr->input will be pointed at the new buffer */
343
344 /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
345 * rr->length bytes of encrypted compressed stuff. */
346
347 /* check is not needed I believe */
348 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH)
349 {
350 al=SSL_AD_RECORD_OVERFLOW;
351 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
352 goto f_err;
353 }
354
355 /* decrypt in place in 'rr->input' */
356 rr->data=rr->input;
357
358 enc_err = s->method->ssl3_enc->enc(s,0);
359 if (enc_err <= 0)
360 {
361 if (enc_err == 0)
362 /* SSLerr() and ssl3_send_alert() have been called */
363 goto err;
364
365 /* otherwise enc_err == -1 */
366 goto decryption_failed_or_bad_record_mac;
367 }
368
369 #ifdef TLS_DEBUG
370 printf("dec %d\n",rr->length);
371 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
372 printf("\n");
373 #endif
374
375 /* r->length is now the compressed data plus mac */
376 if ( (sess == NULL) ||
377 (s->enc_read_ctx == NULL) ||
378 (s->read_hash == NULL))
379 clear=1;
380
381 if (!clear)
382 {
383 mac_size=EVP_MD_size(s->read_hash);
384
385 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+mac_size)
386 {
387 #if 0 /* OK only for stream ciphers (then rr->length is visible from ciphertext anyway) */
388 al=SSL_AD_RECORD_OVERFLOW;
389 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG);
390 goto f_err;
391 #else
392 goto decryption_failed_or_bad_record_mac;
393 #endif
394 }
395 /* check the MAC for rr->input (it's in mac_size bytes at the tail) */
396 if (rr->length < mac_size)
397 {
398 #if 0 /* OK only for stream ciphers */
399 al=SSL_AD_DECODE_ERROR;
400 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_LENGTH_TOO_SHORT);
401 goto f_err;
402 #else
403 goto decryption_failed_or_bad_record_mac;
404 #endif
405 }
406 rr->length-=mac_size;
407 i=s->method->ssl3_enc->mac(s,md,0);
408 if (memcmp(md,&(rr->data[rr->length]),mac_size) != 0)
409 {
410 goto decryption_failed_or_bad_record_mac;
411 }
412 }
413
414 /* r->length is now just compressed */
415 if (s->expand != NULL)
416 {
417 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH)
418 {
419 al=SSL_AD_RECORD_OVERFLOW;
420 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
421 goto f_err;
422 }
423 if (!ssl3_do_uncompress(s))
424 {
425 al=SSL_AD_DECOMPRESSION_FAILURE;
426 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_BAD_DECOMPRESSION);
427 goto f_err;
428 }
429 }
430
431 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH)
432 {
433 al=SSL_AD_RECORD_OVERFLOW;
434 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
435 goto f_err;
436 }
437
438 rr->off=0;
439 /* So at this point the following is true
440 * ssl->s3->rrec.type is the type of record
441 * ssl->s3->rrec.length == number of bytes in record
442 * ssl->s3->rrec.off == offset to first valid byte
443 * ssl->s3->rrec.data == where to take bytes from, increment
444 * after use :-).
445 */
446
447 /* we have pulled in a full packet so zero things */
448 s->packet_length=0;
449 dtls1_record_bitmap_update(s, &(s->d1->bitmap));/* Mark receipt of record. */
450 return(1);
451
452 decryption_failed_or_bad_record_mac:
453 /* Separate 'decryption_failed' alert was introduced with TLS 1.0,
454 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption
455 * failure is directly visible from the ciphertext anyway,
456 * we should not reveal which kind of error occured -- this
457 * might become visible to an attacker (e.g. via logfile) */
458 al=SSL_AD_BAD_RECORD_MAC;
459 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
460 f_err:
461 ssl3_send_alert(s,SSL3_AL_FATAL,al);
462 err:
463 return(0);
464 }
465
466
467 /* Call this to get a new input record.
468 * It will return <= 0 if more data is needed, normally due to an error
469 * or non-blocking IO.
470 * When it finishes, one packet has been decoded and can be found in
471 * ssl->s3->rrec.type - is the type of record
472 * ssl->s3->rrec.data, - data
473 * ssl->s3->rrec.length, - number of bytes
474 */
475 /* used only by dtls1_read_bytes */
476 int dtls1_get_record(SSL *s)
477 {
478 int ssl_major,ssl_minor,al;
479 int i,n;
480 SSL3_RECORD *rr;
481 SSL_SESSION *sess;
482 unsigned char *p;
483 short version;
484 DTLS1_BITMAP *bitmap;
485 BN_ULLONG read_sequence;
486 unsigned int is_next_epoch;
487
488 rr= &(s->s3->rrec);
489 sess=s->session;
490
491 /* The epoch may have changed. If so, process all the
492 * pending records. This is a non-blocking operation. */
493 if ( ! dtls1_process_buffered_records(s))
494 return 0;
495
496 /* if we're renegotiating, then there may be buffered records */
497 if (dtls1_get_processed_record(s))
498 return 1;
499
500 /* get something from the wire */
501 again:
502 /* check if we have the header */
503 if ( (s->rstate != SSL_ST_READ_BODY) ||
504 (s->packet_length < DTLS1_RT_HEADER_LENGTH))
505 {
506 n=ssl3_read_n(s, DTLS1_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
507 /* read timeout is handled by dtls1_read_bytes */
508 if (n <= 0) return(n); /* error or non-blocking */
509
510 OPENSSL_assert(s->packet_length == DTLS1_RT_HEADER_LENGTH);
511
512 s->rstate=SSL_ST_READ_BODY;
513
514 p=s->packet;
515
516 /* Pull apart the header into the DTLS1_RECORD */
517 rr->type= *(p++);
518 ssl_major= *(p++);
519 ssl_minor= *(p++);
520 version=(ssl_major<<8)|ssl_minor;
521
522 /* sequence number is 64 bits, with top 2 bytes = epoch */
523 n2s(p,rr->epoch);
524
525 read_sequence = 0;
526 n2l6(p, read_sequence);
527 long_long_to_bytes(read_sequence, s->s3->read_sequence);
528 n2s(p,rr->length);
529
530 /* Lets check version */
531 if (s->first_packet)
532 {
533 s->first_packet=0;
534 }
535 else
536 {
537 if (version != s->version)
538 {
539 SSLerr(SSL_F_DTLS1_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
540 /* Send back error using their
541 * version number :-) */
542 s->version=version;
543 al=SSL_AD_PROTOCOL_VERSION;
544 goto f_err;
545 }
546 }
547
548 if ((version & 0xff00) != (DTLS1_VERSION & 0xff00))
549 {
550 SSLerr(SSL_F_DTLS1_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
551 goto err;
552 }
553
554 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH)
555 {
556 al=SSL_AD_RECORD_OVERFLOW;
557 SSLerr(SSL_F_DTLS1_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
558 goto f_err;
559 }
560
561 /* now s->rstate == SSL_ST_READ_BODY */
562 }
563
564 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
565
566 if (rr->length > s->packet_length-DTLS1_RT_HEADER_LENGTH)
567 {
568 /* now s->packet_length == DTLS1_RT_HEADER_LENGTH */
569 i=rr->length;
570 n=ssl3_read_n(s,i,i,1);
571 if (n <= 0) return(n); /* error or non-blocking io */
572
573 /* this packet contained a partial record, dump it */
574 if ( n != i)
575 {
576 s->packet_length = 0;
577 goto again;
578 }
579
580 /* now n == rr->length,
581 * and s->packet_length == DTLS1_RT_HEADER_LENGTH + rr->length */
582 }
583 s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
584
585 /* match epochs. NULL means the packet is dropped on the floor */
586 bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch);
587 if ( bitmap == NULL)
588 {
589 s->packet_length = 0; /* dump this record */
590 goto again; /* get another record */
591 }
592
593 /* check whether this is a repeat, or aged record */
594 if ( ! dtls1_record_replay_check(s, bitmap, &(rr->seq_num)))
595 {
596 s->packet_length=0; /* dump this record */
597 goto again; /* get another record */
598 }
599
600 /* just read a 0 length packet */
601 if (rr->length == 0) goto again;
602
603 /* If this record is from the next epoch (either HM or ALERT), buffer it
604 * since it cannot be processed at this time.
605 * Records from the next epoch are marked as received even though they are
606 * not processed, so as to prevent any potential resource DoS attack */
607 if (is_next_epoch)
608 {
609 dtls1_record_bitmap_update(s, bitmap);
610 dtls1_buffer_record(s, &(s->d1->unprocessed_rcds), rr->seq_num);
611 s->packet_length = 0;
612 goto again;
613 }
614
615 if ( ! dtls1_process_record(s))
616 return(0);
617
618 dtls1_clear_timeouts(s); /* done waiting */
619 return(1);
620
621 f_err:
622 ssl3_send_alert(s,SSL3_AL_FATAL,al);
623 err:
624 return(0);
625 }
626
627 /* Return up to 'len' payload bytes received in 'type' records.
628 * 'type' is one of the following:
629 *
630 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
631 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
632 * - 0 (during a shutdown, no data has to be returned)
633 *
634 * If we don't have stored data to work from, read a SSL/TLS record first
635 * (possibly multiple records if we still don't have anything to return).
636 *
637 * This function must handle any surprises the peer may have for us, such as
638 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
639 * a surprise, but handled as if it were), or renegotiation requests.
640 * Also if record payloads contain fragments too small to process, we store
641 * them until there is enough for the respective protocol (the record protocol
642 * may use arbitrary fragmentation and even interleaving):
643 * Change cipher spec protocol
644 * just 1 byte needed, no need for keeping anything stored
645 * Alert protocol
646 * 2 bytes needed (AlertLevel, AlertDescription)
647 * Handshake protocol
648 * 4 bytes needed (HandshakeType, uint24 length) -- we just have
649 * to detect unexpected Client Hello and Hello Request messages
650 * here, anything else is handled by higher layers
651 * Application data protocol
652 * none of our business
653 */
654 int dtls1_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
655 {
656 int al,i,j,ret;
657 unsigned int n;
658 SSL3_RECORD *rr;
659 void (*cb)(const SSL *ssl,int type2,int val)=NULL;
660
661 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
662 if (!ssl3_setup_buffers(s))
663 return(-1);
664
665 /* XXX: check what the second '&& type' is about */
666 if ((type && (type != SSL3_RT_APPLICATION_DATA) &&
667 (type != SSL3_RT_HANDSHAKE) && type) ||
668 (peek && (type != SSL3_RT_APPLICATION_DATA)))
669 {
670 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
671 return -1;
672 }
673
674 /* check whether there's a handshake message (client hello?) waiting */
675 if ( (ret = have_handshake_fragment(s, type, buf, len, peek)))
676 return ret;
677
678 /* Now s->d1->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
679
680 if (!s->in_handshake && SSL_in_init(s))
681 {
682 /* type == SSL3_RT_APPLICATION_DATA */
683 i=s->handshake_func(s);
684 if (i < 0) return(i);
685 if (i == 0)
686 {
687 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
688 return(-1);
689 }
690 }
691
692 start:
693 s->rwstate=SSL_NOTHING;
694
695 /* s->s3->rrec.type - is the type of record
696 * s->s3->rrec.data, - data
697 * s->s3->rrec.off, - offset into 'data' for next read
698 * s->s3->rrec.length, - number of bytes. */
699 rr = &(s->s3->rrec);
700
701 /* get new packet if necessary */
702 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
703 {
704 ret=dtls1_get_record(s);
705 if (ret <= 0)
706 {
707 ret = dtls1_read_failed(s, ret);
708 /* anything other than a timeout is an error */
709 if (ret <= 0)
710 return(ret);
711 else
712 goto start;
713 }
714 }
715
716 /* we now have a packet which can be read and processed */
717
718 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
719 * reset by ssl3_get_finished */
720 && (rr->type != SSL3_RT_HANDSHAKE))
721 {
722 al=SSL_AD_UNEXPECTED_MESSAGE;
723 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
724 goto err;
725 }
726
727 /* If the other end has shut down, throw anything we read away
728 * (even in 'peek' mode) */
729 if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
730 {
731 rr->length=0;
732 s->rwstate=SSL_NOTHING;
733 return(0);
734 }
735
736
737 if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
738 {
739 /* make sure that we are not getting application data when we
740 * are doing a handshake for the first time */
741 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
742 (s->enc_read_ctx == NULL))
743 {
744 al=SSL_AD_UNEXPECTED_MESSAGE;
745 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
746 goto f_err;
747 }
748
749 if (len <= 0) return(len);
750
751 if ((unsigned int)len > rr->length)
752 n = rr->length;
753 else
754 n = (unsigned int)len;
755
756 memcpy(buf,&(rr->data[rr->off]),n);
757 if (!peek)
758 {
759 rr->length-=n;
760 rr->off+=n;
761 if (rr->length == 0)
762 {
763 s->rstate=SSL_ST_READ_HEADER;
764 rr->off=0;
765 }
766 }
767 return(n);
768 }
769
770
771 /* If we get here, then type != rr->type; if we have a handshake
772 * message, then it was unexpected (Hello Request or Client Hello). */
773
774 /* In case of record types for which we have 'fragment' storage,
775 * fill that so that we can process the data at a fixed place.
776 */
777 {
778 unsigned int k, dest_maxlen = 0;
779 unsigned char *dest = NULL;
780 unsigned int *dest_len = NULL;
781
782 if (rr->type == SSL3_RT_HANDSHAKE)
783 {
784 dest_maxlen = sizeof s->d1->handshake_fragment;
785 dest = s->d1->handshake_fragment;
786 dest_len = &s->d1->handshake_fragment_len;
787 }
788 else if (rr->type == SSL3_RT_ALERT)
789 {
790 dest_maxlen = sizeof(s->d1->alert_fragment);
791 dest = s->d1->alert_fragment;
792 dest_len = &s->d1->alert_fragment_len;
793 }
794 else /* else it's a CCS message */
795 OPENSSL_assert(rr->type == SSL3_RT_CHANGE_CIPHER_SPEC);
796
797
798 if (dest_maxlen > 0)
799 {
800 /* XDTLS: In a pathalogical case, the Client Hello
801 * may be fragmented--don't always expect dest_maxlen bytes */
802 if ( rr->length < dest_maxlen)
803 {
804 s->rstate=SSL_ST_READ_HEADER;
805 rr->length = 0;
806 goto start;
807 }
808
809 /* now move 'n' bytes: */
810 for ( k = 0; k < dest_maxlen; k++)
811 {
812 dest[k] = rr->data[rr->off++];
813 rr->length--;
814 }
815 *dest_len = dest_maxlen;
816 }
817 }
818
819 /* s->d1->handshake_fragment_len == 12 iff rr->type == SSL3_RT_HANDSHAKE;
820 * s->d1->alert_fragment_len == 7 iff rr->type == SSL3_RT_ALERT.
821 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
822
823 /* If we are a client, check for an incoming 'Hello Request': */
824 if ((!s->server) &&
825 (s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
826 (s->d1->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
827 (s->session != NULL) && (s->session->cipher != NULL))
828 {
829 s->d1->handshake_fragment_len = 0;
830
831 if ((s->d1->handshake_fragment[1] != 0) ||
832 (s->d1->handshake_fragment[2] != 0) ||
833 (s->d1->handshake_fragment[3] != 0))
834 {
835 al=SSL_AD_DECODE_ERROR;
836 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
837 goto err;
838 }
839
840 /* no need to check sequence number on HELLO REQUEST messages */
841
842 if (s->msg_callback)
843 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
844 s->d1->handshake_fragment, 4, s, s->msg_callback_arg);
845
846 if (SSL_is_init_finished(s) &&
847 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
848 !s->s3->renegotiate)
849 {
850 ssl3_renegotiate(s);
851 if (ssl3_renegotiate_check(s))
852 {
853 i=s->handshake_func(s);
854 if (i < 0) return(i);
855 if (i == 0)
856 {
857 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
858 return(-1);
859 }
860
861 if (!(s->mode & SSL_MODE_AUTO_RETRY))
862 {
863 if (s->s3->rbuf.left == 0) /* no read-ahead left? */
864 {
865 BIO *bio;
866 /* In the case where we try to read application data,
867 * but we trigger an SSL handshake, we return -1 with
868 * the retry option set. Otherwise renegotiation may
869 * cause nasty problems in the blocking world */
870 s->rwstate=SSL_READING;
871 bio=SSL_get_rbio(s);
872 BIO_clear_retry_flags(bio);
873 BIO_set_retry_read(bio);
874 return(-1);
875 }
876 }
877 }
878 }
879 /* we either finished a handshake or ignored the request,
880 * now try again to obtain the (application) data we were asked for */
881 goto start;
882 }
883
884 if (s->d1->alert_fragment_len >= DTLS1_AL_HEADER_LENGTH)
885 {
886 int alert_level = s->d1->alert_fragment[0];
887 int alert_descr = s->d1->alert_fragment[1];
888
889 s->d1->alert_fragment_len = 0;
890
891 if (s->msg_callback)
892 s->msg_callback(0, s->version, SSL3_RT_ALERT,
893 s->d1->alert_fragment, 2, s, s->msg_callback_arg);
894
895 if (s->info_callback != NULL)
896 cb=s->info_callback;
897 else if (s->ctx->info_callback != NULL)
898 cb=s->ctx->info_callback;
899
900 if (cb != NULL)
901 {
902 j = (alert_level << 8) | alert_descr;
903 cb(s, SSL_CB_READ_ALERT, j);
904 }
905
906 if (alert_level == 1) /* warning */
907 {
908 s->s3->warn_alert = alert_descr;
909 if (alert_descr == SSL_AD_CLOSE_NOTIFY)
910 {
911 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
912 return(0);
913 }
914 #if 0
915 /* XXX: this is a possible improvement in the future */
916 /* now check if it's a missing record */
917 if (alert_descr == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE)
918 {
919 unsigned short seq;
920 unsigned int frag_off;
921 unsigned char *p = &(s->d1->alert_fragment[2]);
922
923 n2s(p, seq);
924 n2l3(p, frag_off);
925
926 dtls1_retransmit_message(s, seq, frag_off, &found);
927 if ( ! found && SSL_in_init(s))
928 {
929 /* fprintf( stderr,"in init = %d\n", SSL_in_init(s)); */
930 /* requested a message not yet sent,
931 send an alert ourselves */
932 ssl3_send_alert(s,SSL3_AL_WARNING,
933 DTLS1_AD_MISSING_HANDSHAKE_MESSAGE);
934 }
935 }
936 #endif
937 }
938 else if (alert_level == 2) /* fatal */
939 {
940 char tmp[16];
941
942 s->rwstate=SSL_NOTHING;
943 s->s3->fatal_alert = alert_descr;
944 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
945 BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
946 ERR_add_error_data(2,"SSL alert number ",tmp);
947 s->shutdown|=SSL_RECEIVED_SHUTDOWN;
948 SSL_CTX_remove_session(s->ctx,s->session);
949 return(0);
950 }
951 else
952 {
953 al=SSL_AD_ILLEGAL_PARAMETER;
954 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
955 goto f_err;
956 }
957
958 goto start;
959 }
960
961 if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
962 {
963 s->rwstate=SSL_NOTHING;
964 rr->length=0;
965 return(0);
966 }
967
968 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
969 {
970 struct ccs_header_st ccs_hdr;
971
972 dtls1_get_ccs_header(rr->data, &ccs_hdr);
973
974 if ( ccs_hdr.seq == s->d1->handshake_read_seq)
975 {
976 /* 'Change Cipher Spec' is just a single byte, so we know
977 * exactly what the record payload has to look like */
978 /* XDTLS: check that epoch is consistent */
979 if ( (rr->length != DTLS1_CCS_HEADER_LENGTH) ||
980 (rr->off != 0) || (rr->data[0] != SSL3_MT_CCS))
981 {
982 i=SSL_AD_ILLEGAL_PARAMETER;
983 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
984 goto err;
985 }
986
987 rr->length=0;
988
989 if (s->msg_callback)
990 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC,
991 rr->data, 1, s, s->msg_callback_arg);
992
993 s->s3->change_cipher_spec=1;
994 if (!ssl3_do_change_cipher_spec(s))
995 goto err;
996
997 /* do this whenever CCS is processed */
998 dtls1_reset_seq_numbers(s, SSL3_CC_READ);
999
1000 /* handshake read seq is reset upon handshake completion */
1001 s->d1->handshake_read_seq++;
1002
1003 goto start;
1004 }
1005 else
1006 {
1007 rr->length = 0;
1008 goto start;
1009 }
1010 }
1011
1012 /* Unexpected handshake message (Client Hello, or protocol violation) */
1013 if ((s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
1014 !s->in_handshake)
1015 {
1016 struct hm_header_st msg_hdr;
1017
1018 /* this may just be a stale retransmit */
1019 dtls1_get_message_header(rr->data, &msg_hdr);
1020 if( rr->epoch != s->d1->r_epoch)
1021 {
1022 rr->length = 0;
1023 goto start;
1024 }
1025
1026 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1027 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1028 {
1029 #if 0 /* worked only because C operator preferences are not as expected (and
1030 * because this is not really needed for clients except for detecting
1031 * protocol violations): */
1032 s->state=SSL_ST_BEFORE|(s->server)
1033 ?SSL_ST_ACCEPT
1034 :SSL_ST_CONNECT;
1035 #else
1036 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1037 #endif
1038 s->new_session=1;
1039 }
1040 i=s->handshake_func(s);
1041 if (i < 0) return(i);
1042 if (i == 0)
1043 {
1044 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1045 return(-1);
1046 }
1047
1048 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1049 {
1050 if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1051 {
1052 BIO *bio;
1053 /* In the case where we try to read application data,
1054 * but we trigger an SSL handshake, we return -1 with
1055 * the retry option set. Otherwise renegotiation may
1056 * cause nasty problems in the blocking world */
1057 s->rwstate=SSL_READING;
1058 bio=SSL_get_rbio(s);
1059 BIO_clear_retry_flags(bio);
1060 BIO_set_retry_read(bio);
1061 return(-1);
1062 }
1063 }
1064 goto start;
1065 }
1066
1067 switch (rr->type)
1068 {
1069 default:
1070 #ifndef OPENSSL_NO_TLS
1071 /* TLS just ignores unknown message types */
1072 if (s->version == TLS1_VERSION)
1073 {
1074 rr->length = 0;
1075 goto start;
1076 }
1077 #endif
1078 al=SSL_AD_UNEXPECTED_MESSAGE;
1079 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1080 goto f_err;
1081 case SSL3_RT_CHANGE_CIPHER_SPEC:
1082 case SSL3_RT_ALERT:
1083 case SSL3_RT_HANDSHAKE:
1084 /* we already handled all of these, with the possible exception
1085 * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1086 * should not happen when type != rr->type */
1087 al=SSL_AD_UNEXPECTED_MESSAGE;
1088 SSLerr(SSL_F_DTLS1_READ_BYTES,ERR_R_INTERNAL_ERROR);
1089 goto f_err;
1090 case SSL3_RT_APPLICATION_DATA:
1091 /* At this point, we were expecting handshake data,
1092 * but have application data. If the library was
1093 * running inside ssl3_read() (i.e. in_read_app_data
1094 * is set) and it makes sense to read application data
1095 * at this point (session renegotiation not yet started),
1096 * we will indulge it.
1097 */
1098 if (s->s3->in_read_app_data &&
1099 (s->s3->total_renegotiations != 0) &&
1100 ((
1101 (s->state & SSL_ST_CONNECT) &&
1102 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1103 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1104 ) || (
1105 (s->state & SSL_ST_ACCEPT) &&
1106 (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1107 (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1108 )
1109 ))
1110 {
1111 s->s3->in_read_app_data=2;
1112 return(-1);
1113 }
1114 else
1115 {
1116 al=SSL_AD_UNEXPECTED_MESSAGE;
1117 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1118 goto f_err;
1119 }
1120 }
1121 /* not reached */
1122
1123 f_err:
1124 ssl3_send_alert(s,SSL3_AL_FATAL,al);
1125 err:
1126 return(-1);
1127 }
1128
1129 int
1130 dtls1_write_app_data_bytes(SSL *s, int type, const void *buf_, int len)
1131 {
1132 unsigned int n,tot;
1133 int i;
1134
1135 if (SSL_in_init(s) && !s->in_handshake)
1136 {
1137 i=s->handshake_func(s);
1138 if (i < 0) return(i);
1139 if (i == 0)
1140 {
1141 SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1142 return -1;
1143 }
1144 }
1145
1146 tot = s->s3->wnum;
1147 n = len - tot;
1148
1149 while( n)
1150 {
1151 /* dtls1_write_bytes sends one record at a time, sized according to
1152 * the currently known MTU */
1153 i = dtls1_write_bytes(s, type, buf_, len);
1154 if (i <= 0) return i;
1155
1156 if ((i == (int)n) ||
1157 (type == SSL3_RT_APPLICATION_DATA &&
1158 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
1159 {
1160 /* next chunk of data should get another prepended empty fragment
1161 * in ciphersuites with known-IV weakness: */
1162 s->s3->empty_fragment_done = 0;
1163 return tot+i;
1164 }
1165
1166 tot += i;
1167 n-=i;
1168 }
1169
1170 return tot;
1171 }
1172
1173
1174 /* this only happens when a client hello is received and a handshake
1175 * is started. */
1176 static int
1177 have_handshake_fragment(SSL *s, int type, unsigned char *buf,
1178 int len, int peek)
1179 {
1180
1181 if ((type == SSL3_RT_HANDSHAKE) && (s->d1->handshake_fragment_len > 0))
1182 /* (partially) satisfy request from storage */
1183 {
1184 unsigned char *src = s->d1->handshake_fragment;
1185 unsigned char *dst = buf;
1186 unsigned int k,n;
1187
1188 /* peek == 0 */
1189 n = 0;
1190 while ((len > 0) && (s->d1->handshake_fragment_len > 0))
1191 {
1192 *dst++ = *src++;
1193 len--; s->d1->handshake_fragment_len--;
1194 n++;
1195 }
1196 /* move any remaining fragment bytes: */
1197 for (k = 0; k < s->d1->handshake_fragment_len; k++)
1198 s->d1->handshake_fragment[k] = *src++;
1199 return n;
1200 }
1201
1202 return 0;
1203 }
1204
1205
1206
1207
1208 /* Call this to write data in records of type 'type'
1209 * It will return <= 0 if not all data has been sent or non-blocking IO.
1210 */
1211 int dtls1_write_bytes(SSL *s, int type, const void *buf_, int len)
1212 {
1213 const unsigned char *buf=buf_;
1214 unsigned int tot,n,nw;
1215 int i;
1216 unsigned int mtu;
1217
1218 s->rwstate=SSL_NOTHING;
1219 tot=s->s3->wnum;
1220
1221 n=(len-tot);
1222
1223 /* handshake layer figures out MTU for itself, but data records
1224 * are also sent through this interface, so need to figure out MTU */
1225 #if 0
1226 mtu = BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_GET_MTU, 0, NULL);
1227 mtu += DTLS1_HM_HEADER_LENGTH; /* HM already inserted */
1228 #endif
1229 mtu = s->d1->mtu;
1230
1231 if (mtu > SSL3_RT_MAX_PLAIN_LENGTH)
1232 mtu = SSL3_RT_MAX_PLAIN_LENGTH;
1233
1234 if (n > mtu)
1235 nw=mtu;
1236 else
1237 nw=n;
1238
1239 i=do_dtls1_write(s, type, &(buf[tot]), nw, 0);
1240 if (i <= 0)
1241 {
1242 s->s3->wnum=tot;
1243 return i;
1244 }
1245
1246 if ( (int)s->s3->wnum + i == len)
1247 s->s3->wnum = 0;
1248 else
1249 s->s3->wnum += i;
1250
1251 return tot + i;
1252 }
1253
1254 int do_dtls1_write(SSL *s, int type, const unsigned char *buf, unsigned int len, int create_empty_fragment)
1255 {
1256 unsigned char *p,*pseq;
1257 int i,mac_size,clear=0;
1258 int prefix_len = 0;
1259 SSL3_RECORD *wr;
1260 SSL3_BUFFER *wb;
1261 SSL_SESSION *sess;
1262 int bs;
1263
1264 /* first check if there is a SSL3_BUFFER still being written
1265 * out. This will happen with non blocking IO */
1266 if (s->s3->wbuf.left != 0)
1267 {
1268 OPENSSL_assert(0); /* XDTLS: want to see if we ever get here */
1269 return(ssl3_write_pending(s,type,buf,len));
1270 }
1271
1272 /* If we have an alert to send, lets send it */
1273 if (s->s3->alert_dispatch)
1274 {
1275 i=s->method->ssl_dispatch_alert(s);
1276 if (i <= 0)
1277 return(i);
1278 /* if it went, fall through and send more stuff */
1279 }
1280
1281 if (len == 0 && !create_empty_fragment)
1282 return 0;
1283
1284 wr= &(s->s3->wrec);
1285 wb= &(s->s3->wbuf);
1286 sess=s->session;
1287
1288 if ( (sess == NULL) ||
1289 (s->enc_write_ctx == NULL) ||
1290 (s->write_hash == NULL))
1291 clear=1;
1292
1293 if (clear)
1294 mac_size=0;
1295 else
1296 mac_size=EVP_MD_size(s->write_hash);
1297
1298 /* DTLS implements explicit IV, so no need for empty fragments */
1299 #if 0
1300 /* 'create_empty_fragment' is true only when this function calls itself */
1301 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done
1302 && SSL_version(s) != DTLS1_VERSION)
1303 {
1304 /* countermeasure against known-IV weakness in CBC ciphersuites
1305 * (see http://www.openssl.org/~bodo/tls-cbc.txt)
1306 */
1307
1308 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
1309 {
1310 /* recursive function call with 'create_empty_fragment' set;
1311 * this prepares and buffers the data for an empty fragment
1312 * (these 'prefix_len' bytes are sent out later
1313 * together with the actual payload) */
1314 prefix_len = s->method->do_ssl_write(s, type, buf, 0, 1);
1315 if (prefix_len <= 0)
1316 goto err;
1317
1318 if (s->s3->wbuf.len < (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE)
1319 {
1320 /* insufficient space */
1321 SSLerr(SSL_F_DO_DTLS1_WRITE, ERR_R_INTERNAL_ERROR);
1322 goto err;
1323 }
1324 }
1325
1326 s->s3->empty_fragment_done = 1;
1327 }
1328 #endif
1329
1330 p = wb->buf + prefix_len;
1331
1332 /* write the header */
1333
1334 *(p++)=type&0xff;
1335 wr->type=type;
1336
1337 *(p++)=(s->version>>8);
1338 *(p++)=s->version&0xff;
1339
1340 /* field where we are to write out packet epoch, seq num and len */
1341 pseq=p;
1342 p+=10;
1343
1344 /* lets setup the record stuff. */
1345
1346 /* Make space for the explicit IV in case of CBC.
1347 * (this is a bit of a boundary violation, but what the heck).
1348 */
1349 if ( s->enc_write_ctx &&
1350 (EVP_CIPHER_mode( s->enc_write_ctx->cipher ) & EVP_CIPH_CBC_MODE))
1351 bs = EVP_CIPHER_block_size(s->enc_write_ctx->cipher);
1352 else
1353 bs = 0;
1354
1355 wr->data=p + bs; /* make room for IV in case of CBC */
1356 wr->length=(int)len;
1357 wr->input=(unsigned char *)buf;
1358
1359 /* we now 'read' from wr->input, wr->length bytes into
1360 * wr->data */
1361
1362 /* first we compress */
1363 if (s->compress != NULL)
1364 {
1365 if (!ssl3_do_compress(s))
1366 {
1367 SSLerr(SSL_F_DO_DTLS1_WRITE,SSL_R_COMPRESSION_FAILURE);
1368 goto err;
1369 }
1370 }
1371 else
1372 {
1373 memcpy(wr->data,wr->input,wr->length);
1374 wr->input=wr->data;
1375 }
1376
1377 /* we should still have the output to wr->data and the input
1378 * from wr->input. Length should be wr->length.
1379 * wr->data still points in the wb->buf */
1380
1381 if (mac_size != 0)
1382 {
1383 s->method->ssl3_enc->mac(s,&(p[wr->length + bs]),1);
1384 wr->length+=mac_size;
1385 }
1386
1387 /* this is true regardless of mac size */
1388 wr->input=p;
1389 wr->data=p;
1390
1391
1392 /* ssl3_enc can only have an error on read */
1393 wr->length += bs; /* bs != 0 in case of CBC. The enc fn provides
1394 * the randomness */
1395 s->method->ssl3_enc->enc(s,1);
1396
1397 /* record length after mac and block padding */
1398 /* if (type == SSL3_RT_APPLICATION_DATA ||
1399 (type == SSL3_RT_ALERT && ! SSL_in_init(s))) */
1400
1401 /* there's only one epoch between handshake and app data */
1402
1403 s2n(s->d1->w_epoch, pseq);
1404
1405 /* XDTLS: ?? */
1406 /* else
1407 s2n(s->d1->handshake_epoch, pseq); */
1408
1409 l2n6(bytes_to_long_long(s->s3->write_sequence), pseq);
1410 s2n(wr->length,pseq);
1411
1412 /* we should now have
1413 * wr->data pointing to the encrypted data, which is
1414 * wr->length long */
1415 wr->type=type; /* not needed but helps for debugging */
1416 wr->length+=DTLS1_RT_HEADER_LENGTH;
1417
1418 #if 0 /* this is now done at the message layer */
1419 /* buffer the record, making it easy to handle retransmits */
1420 if ( type == SSL3_RT_HANDSHAKE || type == SSL3_RT_CHANGE_CIPHER_SPEC)
1421 dtls1_buffer_record(s, wr->data, wr->length,
1422 *((BN_ULLONG *)&(s->s3->write_sequence[0])));
1423 #endif
1424
1425 ssl3_record_sequence_update(&(s->s3->write_sequence[0]));
1426
1427 if (create_empty_fragment)
1428 {
1429 /* we are in a recursive call;
1430 * just return the length, don't write out anything here
1431 */
1432 return wr->length;
1433 }
1434
1435 /* now let's set up wb */
1436 wb->left = prefix_len + wr->length;
1437 wb->offset = 0;
1438
1439 /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
1440 s->s3->wpend_tot=len;
1441 s->s3->wpend_buf=buf;
1442 s->s3->wpend_type=type;
1443 s->s3->wpend_ret=len;
1444
1445 /* we now just need to write the buffer */
1446 return ssl3_write_pending(s,type,buf,len);
1447 err:
1448 return -1;
1449 }
1450
1451
1452
1453 static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap,
1454 BN_ULLONG *seq_num)
1455 {
1456 BN_ULLONG mask = 0x0000000000000001L;
1457 BN_ULLONG rcd_num;
1458
1459 rcd_num = bytes_to_long_long(s->s3->read_sequence);
1460
1461 if (rcd_num >= bitmap->max_seq_num)
1462 {
1463 *seq_num = rcd_num;
1464 return 1; /* this record is new */
1465 }
1466
1467 if (bitmap->max_seq_num - rcd_num > bitmap->length)
1468 return 0; /* stale, outside the window */
1469
1470 mask <<= (bitmap->max_seq_num - rcd_num - 1);
1471 if (bitmap->map & mask)
1472 return 0; /* record previously received */
1473
1474 *seq_num = rcd_num;
1475 return 1;
1476 }
1477
1478
1479 static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap)
1480 {
1481 unsigned int shift;
1482 BN_ULLONG mask = 0x0000000000000001L;
1483 BN_ULLONG rcd_num;
1484
1485 rcd_num = bytes_to_long_long(s->s3->read_sequence);
1486
1487 if (rcd_num >= bitmap->max_seq_num)
1488 {
1489 shift = (unsigned int)(rcd_num - bitmap->max_seq_num) + 1;
1490 bitmap->max_seq_num = rcd_num + 1;
1491 bitmap->map <<= shift;
1492 bitmap->map |= 0x0000000000000001L;
1493 }
1494 else
1495 {
1496 mask <<= (bitmap->max_seq_num - rcd_num - 1);
1497 bitmap->map |= mask;
1498 }
1499 }
1500
1501
1502 int dtls1_dispatch_alert(SSL *s)
1503 {
1504 int i,j;
1505 void (*cb)(const SSL *ssl,int type,int val)=NULL;
1506 unsigned char buf[2 + 2 + 3]; /* alert level + alert desc + message seq +frag_off */
1507 unsigned char *ptr = &buf[0];
1508
1509 s->s3->alert_dispatch=0;
1510
1511 memset(buf, 0x00, sizeof(buf));
1512 *ptr++ = s->s3->send_alert[0];
1513 *ptr++ = s->s3->send_alert[1];
1514
1515 if (s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE)
1516 {
1517 s2n(s->d1->handshake_read_seq, ptr);
1518 #if 0
1519 if ( s->d1->r_msg_hdr.frag_off == 0) /* waiting for a new msg */
1520
1521 else
1522 s2n(s->d1->r_msg_hdr.seq, ptr); /* partial msg read */
1523 #endif
1524
1525 #if 0
1526 fprintf(stderr, "s->d1->handshake_read_seq = %d, s->d1->r_msg_hdr.seq = %d\n",s->d1->handshake_read_seq,s->d1->r_msg_hdr.seq);
1527 #endif
1528 l2n3(s->d1->r_msg_hdr.frag_off, ptr);
1529 }
1530
1531 i = do_dtls1_write(s, SSL3_RT_ALERT, &buf[0], sizeof(buf), 0);
1532 if (i <= 0)
1533 {
1534 s->s3->alert_dispatch=1;
1535 /* fprintf( stderr, "not done with alert\n" ); */
1536 }
1537 else
1538 {
1539 if ( s->s3->send_alert[0] == SSL3_AL_FATAL ||
1540 s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE)
1541 (void)BIO_flush(s->wbio);
1542
1543 if (s->msg_callback)
1544 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert,
1545 2, s, s->msg_callback_arg);
1546
1547 if (s->info_callback != NULL)
1548 cb=s->info_callback;
1549 else if (s->ctx->info_callback != NULL)
1550 cb=s->ctx->info_callback;
1551
1552 if (cb != NULL)
1553 {
1554 j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1555 cb(s,SSL_CB_WRITE_ALERT,j);
1556 }
1557 }
1558 return(i);
1559 }
1560
1561
1562 static DTLS1_BITMAP *
1563 dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr, unsigned int *is_next_epoch)
1564 {
1565
1566 *is_next_epoch = 0;
1567
1568 /* In current epoch, accept HM, CCS, DATA, & ALERT */
1569 if (rr->epoch == s->d1->r_epoch)
1570 return &s->d1->bitmap;
1571
1572 /* Only HM and ALERT messages can be from the next epoch */
1573 else if (rr->epoch == (unsigned long)(s->d1->r_epoch + 1) &&
1574 (rr->type == SSL3_RT_HANDSHAKE ||
1575 rr->type == SSL3_RT_ALERT))
1576 {
1577 *is_next_epoch = 1;
1578 return &s->d1->next_bitmap;
1579 }
1580
1581 return NULL;
1582 }
1583
1584 #if 0
1585 static int
1586 dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr, unsigned short *priority,
1587 unsigned long *offset)
1588 {
1589
1590 /* alerts are passed up immediately */
1591 if ( rr->type == SSL3_RT_APPLICATION_DATA ||
1592 rr->type == SSL3_RT_ALERT)
1593 return 0;
1594
1595 /* Only need to buffer if a handshake is underway.
1596 * (this implies that Hello Request and Client Hello are passed up
1597 * immediately) */
1598 if ( SSL_in_init(s))
1599 {
1600 unsigned char *data = rr->data;
1601 /* need to extract the HM/CCS sequence number here */
1602 if ( rr->type == SSL3_RT_HANDSHAKE ||
1603 rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1604 {
1605 unsigned short seq_num;
1606 struct hm_header_st msg_hdr;
1607 struct ccs_header_st ccs_hdr;
1608
1609 if ( rr->type == SSL3_RT_HANDSHAKE)
1610 {
1611 dtls1_get_message_header(data, &msg_hdr);
1612 seq_num = msg_hdr.seq;
1613 *offset = msg_hdr.frag_off;
1614 }
1615 else
1616 {
1617 dtls1_get_ccs_header(data, &ccs_hdr);
1618 seq_num = ccs_hdr.seq;
1619 *offset = 0;
1620 }
1621
1622 /* this is either a record we're waiting for, or a
1623 * retransmit of something we happened to previously
1624 * receive (higher layers will drop the repeat silently */
1625 if ( seq_num < s->d1->handshake_read_seq)
1626 return 0;
1627 if (rr->type == SSL3_RT_HANDSHAKE &&
1628 seq_num == s->d1->handshake_read_seq &&
1629 msg_hdr.frag_off < s->d1->r_msg_hdr.frag_off)
1630 return 0;
1631 else if ( seq_num == s->d1->handshake_read_seq &&
1632 (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC ||
1633 msg_hdr.frag_off == s->d1->r_msg_hdr.frag_off))
1634 return 0;
1635 else
1636 {
1637 *priority = seq_num;
1638 return 1;
1639 }
1640 }
1641 else /* unknown record type */
1642 return 0;
1643 }
1644
1645 return 0;
1646 }
1647 #endif
1648
1649 void
1650 dtls1_reset_seq_numbers(SSL *s, int rw)
1651 {
1652 unsigned char *seq;
1653 unsigned int seq_bytes = sizeof(s->s3->read_sequence);
1654
1655 if ( rw & SSL3_CC_READ)
1656 {
1657 seq = s->s3->read_sequence;
1658 s->d1->r_epoch++;
1659 memcpy(&(s->d1->bitmap), &(s->d1->next_bitmap), sizeof(DTLS1_BITMAP));
1660 memset(&(s->d1->next_bitmap), 0x00, sizeof(DTLS1_BITMAP));
1661 }
1662 else
1663 {
1664 seq = s->s3->write_sequence;
1665 s->d1->w_epoch++;
1666 }
1667
1668 memset(seq, 0x00, seq_bytes);
1669 }
1670
1671
1672 static BN_ULLONG
1673 bytes_to_long_long(unsigned char *bytes)
1674 {
1675 BN_ULLONG num;
1676
1677 num = (((BN_ULLONG)bytes[0]) << 56) |
1678 (((BN_ULLONG)bytes[1]) << 48) |
1679 (((BN_ULLONG)bytes[2]) << 40) |
1680 (((BN_ULLONG)bytes[3]) << 32) |
1681 (((BN_ULLONG)bytes[4]) << 24) |
1682 (((BN_ULLONG)bytes[5]) << 16) |
1683 (((BN_ULLONG)bytes[6]) << 8) |
1684 (((BN_ULLONG)bytes[7]) );
1685
1686 return num;
1687 }
1688
1689 static void
1690 long_long_to_bytes(BN_ULLONG num, unsigned char *bytes)
1691 {
1692 bytes[0] = (unsigned char)((num >> 56)&0xff);
1693 bytes[1] = (unsigned char)((num >> 48)&0xff);
1694 bytes[2] = (unsigned char)((num >> 40)&0xff);
1695 bytes[3] = (unsigned char)((num >> 32)&0xff);
1696 bytes[4] = (unsigned char)((num >> 24)&0xff);
1697 bytes[5] = (unsigned char)((num >> 16)&0xff);
1698 bytes[6] = (unsigned char)((num >> 8)&0xff);
1699 bytes[7] = (unsigned char)((num )&0xff);
1700 }
1701
1702 static void
1703 dtls1_clear_timeouts(SSL *s)
1704 {
1705 memset(&(s->d1->timeout), 0x00, sizeof(struct dtls1_timeout_st));
1706 }
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