Import OpenSSL 0.9.8e.
[dragonfly.git] / crypto / openssl-0.9 / ssl / d1_pkt.c
CommitLineData
56276539
SS
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
124static int have_handshake_fragment(SSL *s, int type, unsigned char *buf,
125 int len, int peek);
126static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap,
127 PQ_64BIT *seq_num);
128static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap);
129static DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr,
130 unsigned int *is_next_epoch);
131#if 0
132static int dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr,
133 unsigned short *priority, unsigned long *offset);
134#endif
135static int dtls1_buffer_record(SSL *s, record_pqueue *q,
136 PQ_64BIT priority);
137static int dtls1_process_record(SSL *s);
138#if PQ_64BIT_IS_INTEGER
139static PQ_64BIT bytes_to_long_long(unsigned char *bytes, PQ_64BIT *num);
140#endif
141static void dtls1_clear_timeouts(SSL *s);
142
143/* copy buffered record into SSL structure */
144static int
145dtls1_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
163static int
164dtls1_buffer_record(SSL *s, record_pqueue *queue, PQ_64BIT 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
74093195
SS
200 if (!ssl3_setup_buffers(s))
201 {
202 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
203 OPENSSL_free(rdata);
204 pitem_free(item);
205 return(0);
206 }
56276539
SS
207
208 return(1);
209 }
210
211
212static int
213dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue)
214 {
215 pitem *item;
216
217 item = pqueue_pop(queue->q);
218 if (item)
219 {
220 dtls1_copy_record(s, item);
221
222 OPENSSL_free(item->data);
223 pitem_free(item);
224
225 return(1);
226 }
227
228 return(0);
229 }
230
231
232/* retrieve a buffered record that belongs to the new epoch, i.e., not processed
233 * yet */
234#define dtls1_get_unprocessed_record(s) \
235 dtls1_retrieve_buffered_record((s), \
236 &((s)->d1->unprocessed_rcds))
237
238/* retrieve a buffered record that belongs to the current epoch, ie, processed */
239#define dtls1_get_processed_record(s) \
240 dtls1_retrieve_buffered_record((s), \
241 &((s)->d1->processed_rcds))
242
243static int
244dtls1_process_buffered_records(SSL *s)
245 {
246 pitem *item;
247
248 item = pqueue_peek(s->d1->unprocessed_rcds.q);
249 if (item)
250 {
251 DTLS1_RECORD_DATA *rdata;
252 rdata = (DTLS1_RECORD_DATA *)item->data;
253
254 /* Check if epoch is current. */
255 if (s->d1->unprocessed_rcds.epoch != s->d1->r_epoch)
256 return(1); /* Nothing to do. */
257
258 /* Process all the records. */
259 while (pqueue_peek(s->d1->unprocessed_rcds.q))
260 {
261 dtls1_get_unprocessed_record(s);
262 if ( ! dtls1_process_record(s))
263 return(0);
264 dtls1_buffer_record(s, &(s->d1->processed_rcds),
265 s->s3->rrec.seq_num);
266 }
267 }
268
269 /* sync epoch numbers once all the unprocessed records
270 * have been processed */
271 s->d1->processed_rcds.epoch = s->d1->r_epoch;
272 s->d1->unprocessed_rcds.epoch = s->d1->r_epoch + 1;
273
274 return(1);
275 }
276
277
278#if 0
279
280static int
281dtls1_get_buffered_record(SSL *s)
282 {
283 pitem *item;
284 PQ_64BIT priority =
285 (((PQ_64BIT)s->d1->handshake_read_seq) << 32) |
286 ((PQ_64BIT)s->d1->r_msg_hdr.frag_off);
287
288 if ( ! SSL_in_init(s)) /* if we're not (re)negotiating,
289 nothing buffered */
290 return 0;
291
292
293 item = pqueue_peek(s->d1->rcvd_records);
294 if (item && item->priority == priority)
295 {
296 /* Check if we've received the record of interest. It must be
297 * a handshake record, since data records as passed up without
298 * buffering */
299 DTLS1_RECORD_DATA *rdata;
300 item = pqueue_pop(s->d1->rcvd_records);
301 rdata = (DTLS1_RECORD_DATA *)item->data;
302
303 if (s->s3->rbuf.buf != NULL)
304 OPENSSL_free(s->s3->rbuf.buf);
305
306 s->packet = rdata->packet;
307 s->packet_length = rdata->packet_length;
308 memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER));
309 memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD));
310
311 OPENSSL_free(item->data);
312 pitem_free(item);
313
314 /* s->d1->next_expected_seq_num++; */
315 return(1);
316 }
317
318 return 0;
319 }
320
321#endif
322
323static int
324dtls1_process_record(SSL *s)
325{
326 int i,al;
327 int clear=0;
328 int enc_err;
329 SSL_SESSION *sess;
330 SSL3_RECORD *rr;
331 unsigned int mac_size;
332 unsigned char md[EVP_MAX_MD_SIZE];
333
334
335 rr= &(s->s3->rrec);
336 sess = s->session;
337
338 /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
339 * and we have that many bytes in s->packet
340 */
341 rr->input= &(s->packet[DTLS1_RT_HEADER_LENGTH]);
342
343 /* ok, we can now read from 's->packet' data into 'rr'
344 * rr->input points at rr->length bytes, which
345 * need to be copied into rr->data by either
346 * the decryption or by the decompression
347 * When the data is 'copied' into the rr->data buffer,
348 * rr->input will be pointed at the new buffer */
349
350 /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
351 * rr->length bytes of encrypted compressed stuff. */
352
353 /* check is not needed I believe */
354 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH)
355 {
356 al=SSL_AD_RECORD_OVERFLOW;
357 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
358 goto f_err;
359 }
360
361 /* decrypt in place in 'rr->input' */
362 rr->data=rr->input;
363
364 enc_err = s->method->ssl3_enc->enc(s,0);
365 if (enc_err <= 0)
366 {
367 if (enc_err == 0)
368 /* SSLerr() and ssl3_send_alert() have been called */
369 goto err;
370
371 /* otherwise enc_err == -1 */
372 goto decryption_failed_or_bad_record_mac;
373 }
374
375#ifdef TLS_DEBUG
376printf("dec %d\n",rr->length);
377{ unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
378printf("\n");
379#endif
380
381 /* r->length is now the compressed data plus mac */
382if ( (sess == NULL) ||
383 (s->enc_read_ctx == NULL) ||
384 (s->read_hash == NULL))
385 clear=1;
386
387 if (!clear)
388 {
389 mac_size=EVP_MD_size(s->read_hash);
390
391 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+mac_size)
392 {
393#if 0 /* OK only for stream ciphers (then rr->length is visible from ciphertext anyway) */
394 al=SSL_AD_RECORD_OVERFLOW;
395 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG);
396 goto f_err;
397#else
398 goto decryption_failed_or_bad_record_mac;
399#endif
400 }
401 /* check the MAC for rr->input (it's in mac_size bytes at the tail) */
402 if (rr->length < mac_size)
403 {
404#if 0 /* OK only for stream ciphers */
405 al=SSL_AD_DECODE_ERROR;
406 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_LENGTH_TOO_SHORT);
407 goto f_err;
408#else
409 goto decryption_failed_or_bad_record_mac;
410#endif
411 }
412 rr->length-=mac_size;
413 i=s->method->ssl3_enc->mac(s,md,0);
414 if (memcmp(md,&(rr->data[rr->length]),mac_size) != 0)
415 {
416 goto decryption_failed_or_bad_record_mac;
417 }
418 }
419
420 /* r->length is now just compressed */
421 if (s->expand != NULL)
422 {
423 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH)
424 {
425 al=SSL_AD_RECORD_OVERFLOW;
426 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
427 goto f_err;
428 }
429 if (!ssl3_do_uncompress(s))
430 {
431 al=SSL_AD_DECOMPRESSION_FAILURE;
432 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_BAD_DECOMPRESSION);
433 goto f_err;
434 }
435 }
436
437 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH)
438 {
439 al=SSL_AD_RECORD_OVERFLOW;
440 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
441 goto f_err;
442 }
443
444 rr->off=0;
445 /* So at this point the following is true
446 * ssl->s3->rrec.type is the type of record
447 * ssl->s3->rrec.length == number of bytes in record
448 * ssl->s3->rrec.off == offset to first valid byte
449 * ssl->s3->rrec.data == where to take bytes from, increment
450 * after use :-).
451 */
452
453 /* we have pulled in a full packet so zero things */
454 s->packet_length=0;
455 dtls1_record_bitmap_update(s, &(s->d1->bitmap));/* Mark receipt of record. */
456 return(1);
457
458decryption_failed_or_bad_record_mac:
459 /* Separate 'decryption_failed' alert was introduced with TLS 1.0,
460 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption
461 * failure is directly visible from the ciphertext anyway,
462 * we should not reveal which kind of error occured -- this
463 * might become visible to an attacker (e.g. via logfile) */
464 al=SSL_AD_BAD_RECORD_MAC;
465 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
466f_err:
467 ssl3_send_alert(s,SSL3_AL_FATAL,al);
468err:
469 return(0);
470}
471
472
473/* Call this to get a new input record.
474 * It will return <= 0 if more data is needed, normally due to an error
475 * or non-blocking IO.
476 * When it finishes, one packet has been decoded and can be found in
477 * ssl->s3->rrec.type - is the type of record
478 * ssl->s3->rrec.data, - data
479 * ssl->s3->rrec.length, - number of bytes
480 */
481/* used only by dtls1_read_bytes */
482int dtls1_get_record(SSL *s)
483 {
484 int ssl_major,ssl_minor,al;
485 int i,n;
486 SSL3_RECORD *rr;
487 SSL_SESSION *sess;
488 unsigned char *p;
489 short version;
490 DTLS1_BITMAP *bitmap;
491 unsigned int is_next_epoch;
492
493 rr= &(s->s3->rrec);
494 sess=s->session;
495
496 /* The epoch may have changed. If so, process all the
497 * pending records. This is a non-blocking operation. */
498 if ( ! dtls1_process_buffered_records(s))
499 return 0;
500
501 /* if we're renegotiating, then there may be buffered records */
502 if (dtls1_get_processed_record(s))
503 return 1;
504
505 /* get something from the wire */
506again:
507 /* check if we have the header */
508 if ( (s->rstate != SSL_ST_READ_BODY) ||
509 (s->packet_length < DTLS1_RT_HEADER_LENGTH))
510 {
511 n=ssl3_read_n(s, DTLS1_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
512 /* read timeout is handled by dtls1_read_bytes */
513 if (n <= 0) return(n); /* error or non-blocking */
514
515 OPENSSL_assert(s->packet_length == DTLS1_RT_HEADER_LENGTH);
516
517 s->rstate=SSL_ST_READ_BODY;
518
519 p=s->packet;
520
521 /* Pull apart the header into the DTLS1_RECORD */
522 rr->type= *(p++);
523 ssl_major= *(p++);
524 ssl_minor= *(p++);
525 version=(ssl_major<<8)|ssl_minor;
526
527 /* sequence number is 64 bits, with top 2 bytes = epoch */
528 n2s(p,rr->epoch);
529
530 memcpy(&(s->s3->read_sequence[2]), p, 6);
531 p+=6;
532
533 n2s(p,rr->length);
534
535 /* Lets check version */
e40c9513 536 if (!s->first_packet)
56276539
SS
537 {
538 if (version != s->version)
539 {
540 SSLerr(SSL_F_DTLS1_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
541 /* Send back error using their
542 * version number :-) */
543 s->version=version;
544 al=SSL_AD_PROTOCOL_VERSION;
545 goto f_err;
546 }
547 }
548
549 if ((version & 0xff00) != (DTLS1_VERSION & 0xff00))
550 {
551 SSLerr(SSL_F_DTLS1_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
552 goto err;
553 }
554
555 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH)
556 {
557 al=SSL_AD_RECORD_OVERFLOW;
558 SSLerr(SSL_F_DTLS1_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
559 goto f_err;
560 }
561
562 /* now s->rstate == SSL_ST_READ_BODY */
563 }
564
565 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
566
567 if (rr->length > s->packet_length-DTLS1_RT_HEADER_LENGTH)
568 {
569 /* now s->packet_length == DTLS1_RT_HEADER_LENGTH */
570 i=rr->length;
571 n=ssl3_read_n(s,i,i,1);
572 if (n <= 0) return(n); /* error or non-blocking io */
573
574 /* this packet contained a partial record, dump it */
575 if ( n != i)
576 {
577 s->packet_length = 0;
578 goto again;
579 }
580
581 /* now n == rr->length,
582 * and s->packet_length == DTLS1_RT_HEADER_LENGTH + rr->length */
583 }
584 s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
585
586 /* match epochs. NULL means the packet is dropped on the floor */
587 bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch);
588 if ( bitmap == NULL)
589 {
590 s->packet_length = 0; /* dump this record */
591 goto again; /* get another record */
592 }
593
594 /* check whether this is a repeat, or aged record */
595 if ( ! dtls1_record_replay_check(s, bitmap, &(rr->seq_num)))
596 {
597 s->packet_length=0; /* dump this record */
598 goto again; /* get another record */
599 }
600
601 /* just read a 0 length packet */
602 if (rr->length == 0) goto again;
603
604 /* If this record is from the next epoch (either HM or ALERT), buffer it
605 * since it cannot be processed at this time.
606 * Records from the next epoch are marked as received even though they are
607 * not processed, so as to prevent any potential resource DoS attack */
608 if (is_next_epoch)
609 {
610 dtls1_record_bitmap_update(s, bitmap);
611 dtls1_buffer_record(s, &(s->d1->unprocessed_rcds), rr->seq_num);
612 s->packet_length = 0;
613 goto again;
614 }
615
616 if ( ! dtls1_process_record(s))
617 return(0);
618
619 dtls1_clear_timeouts(s); /* done waiting */
620 return(1);
621
622f_err:
623 ssl3_send_alert(s,SSL3_AL_FATAL,al);
624err:
625 return(0);
626 }
627
628/* Return up to 'len' payload bytes received in 'type' records.
629 * 'type' is one of the following:
630 *
631 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
632 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
633 * - 0 (during a shutdown, no data has to be returned)
634 *
635 * If we don't have stored data to work from, read a SSL/TLS record first
636 * (possibly multiple records if we still don't have anything to return).
637 *
638 * This function must handle any surprises the peer may have for us, such as
639 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
640 * a surprise, but handled as if it were), or renegotiation requests.
641 * Also if record payloads contain fragments too small to process, we store
642 * them until there is enough for the respective protocol (the record protocol
643 * may use arbitrary fragmentation and even interleaving):
644 * Change cipher spec protocol
645 * just 1 byte needed, no need for keeping anything stored
646 * Alert protocol
647 * 2 bytes needed (AlertLevel, AlertDescription)
648 * Handshake protocol
649 * 4 bytes needed (HandshakeType, uint24 length) -- we just have
650 * to detect unexpected Client Hello and Hello Request messages
651 * here, anything else is handled by higher layers
652 * Application data protocol
653 * none of our business
654 */
655int dtls1_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
656 {
657 int al,i,j,ret;
658 unsigned int n;
659 SSL3_RECORD *rr;
660 void (*cb)(const SSL *ssl,int type2,int val)=NULL;
661
662 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
663 if (!ssl3_setup_buffers(s))
664 return(-1);
665
666 /* XXX: check what the second '&& type' is about */
667 if ((type && (type != SSL3_RT_APPLICATION_DATA) &&
668 (type != SSL3_RT_HANDSHAKE) && type) ||
669 (peek && (type != SSL3_RT_APPLICATION_DATA)))
670 {
671 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
672 return -1;
673 }
674
675 /* check whether there's a handshake message (client hello?) waiting */
676 if ( (ret = have_handshake_fragment(s, type, buf, len, peek)))
677 return ret;
678
679 /* Now s->d1->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
680
681 if (!s->in_handshake && SSL_in_init(s))
682 {
683 /* type == SSL3_RT_APPLICATION_DATA */
684 i=s->handshake_func(s);
685 if (i < 0) return(i);
686 if (i == 0)
687 {
688 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
689 return(-1);
690 }
691 }
692
693start:
694 s->rwstate=SSL_NOTHING;
695
696 /* s->s3->rrec.type - is the type of record
697 * s->s3->rrec.data, - data
698 * s->s3->rrec.off, - offset into 'data' for next read
699 * s->s3->rrec.length, - number of bytes. */
700 rr = &(s->s3->rrec);
701
702 /* get new packet if necessary */
703 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
704 {
705 ret=dtls1_get_record(s);
706 if (ret <= 0)
707 {
708 ret = dtls1_read_failed(s, ret);
709 /* anything other than a timeout is an error */
710 if (ret <= 0)
711 return(ret);
712 else
713 goto start;
714 }
715 }
716
717 /* we now have a packet which can be read and processed */
718
719 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
720 * reset by ssl3_get_finished */
721 && (rr->type != SSL3_RT_HANDSHAKE))
722 {
723 al=SSL_AD_UNEXPECTED_MESSAGE;
724 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
725 goto err;
726 }
727
728 /* If the other end has shut down, throw anything we read away
729 * (even in 'peek' mode) */
730 if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
731 {
732 rr->length=0;
733 s->rwstate=SSL_NOTHING;
734 return(0);
735 }
736
737
738 if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
739 {
740 /* make sure that we are not getting application data when we
741 * are doing a handshake for the first time */
742 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
743 (s->enc_read_ctx == NULL))
744 {
745 al=SSL_AD_UNEXPECTED_MESSAGE;
746 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
747 goto f_err;
748 }
749
750 if (len <= 0) return(len);
751
752 if ((unsigned int)len > rr->length)
753 n = rr->length;
754 else
755 n = (unsigned int)len;
756
757 memcpy(buf,&(rr->data[rr->off]),n);
758 if (!peek)
759 {
760 rr->length-=n;
761 rr->off+=n;
762 if (rr->length == 0)
763 {
764 s->rstate=SSL_ST_READ_HEADER;
765 rr->off=0;
766 }
767 }
768 return(n);
769 }
770
771
772 /* If we get here, then type != rr->type; if we have a handshake
773 * message, then it was unexpected (Hello Request or Client Hello). */
774
775 /* In case of record types for which we have 'fragment' storage,
776 * fill that so that we can process the data at a fixed place.
777 */
778 {
779 unsigned int k, dest_maxlen = 0;
780 unsigned char *dest = NULL;
781 unsigned int *dest_len = NULL;
782
783 if (rr->type == SSL3_RT_HANDSHAKE)
784 {
785 dest_maxlen = sizeof s->d1->handshake_fragment;
786 dest = s->d1->handshake_fragment;
787 dest_len = &s->d1->handshake_fragment_len;
788 }
789 else if (rr->type == SSL3_RT_ALERT)
790 {
791 dest_maxlen = sizeof(s->d1->alert_fragment);
792 dest = s->d1->alert_fragment;
793 dest_len = &s->d1->alert_fragment_len;
794 }
3b25c29b
PA
795 /* else it's a CCS message, or it's wrong */
796 else if (rr->type != SSL3_RT_CHANGE_CIPHER_SPEC)
797 {
798 /* Not certain if this is the right error handling */
799 al=SSL_AD_UNEXPECTED_MESSAGE;
800 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
801 goto f_err;
802 }
56276539
SS
803
804
805 if (dest_maxlen > 0)
806 {
807 /* XDTLS: In a pathalogical case, the Client Hello
808 * may be fragmented--don't always expect dest_maxlen bytes */
809 if ( rr->length < dest_maxlen)
810 {
811 s->rstate=SSL_ST_READ_HEADER;
812 rr->length = 0;
813 goto start;
814 }
815
816 /* now move 'n' bytes: */
817 for ( k = 0; k < dest_maxlen; k++)
818 {
819 dest[k] = rr->data[rr->off++];
820 rr->length--;
821 }
822 *dest_len = dest_maxlen;
823 }
824 }
825
826 /* s->d1->handshake_fragment_len == 12 iff rr->type == SSL3_RT_HANDSHAKE;
827 * s->d1->alert_fragment_len == 7 iff rr->type == SSL3_RT_ALERT.
828 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
829
830 /* If we are a client, check for an incoming 'Hello Request': */
831 if ((!s->server) &&
832 (s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
833 (s->d1->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
834 (s->session != NULL) && (s->session->cipher != NULL))
835 {
836 s->d1->handshake_fragment_len = 0;
837
838 if ((s->d1->handshake_fragment[1] != 0) ||
839 (s->d1->handshake_fragment[2] != 0) ||
840 (s->d1->handshake_fragment[3] != 0))
841 {
842 al=SSL_AD_DECODE_ERROR;
843 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
844 goto err;
845 }
846
847 /* no need to check sequence number on HELLO REQUEST messages */
848
849 if (s->msg_callback)
850 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
851 s->d1->handshake_fragment, 4, s, s->msg_callback_arg);
852
853 if (SSL_is_init_finished(s) &&
854 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
855 !s->s3->renegotiate)
856 {
857 ssl3_renegotiate(s);
858 if (ssl3_renegotiate_check(s))
859 {
860 i=s->handshake_func(s);
861 if (i < 0) return(i);
862 if (i == 0)
863 {
864 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
865 return(-1);
866 }
867
868 if (!(s->mode & SSL_MODE_AUTO_RETRY))
869 {
870 if (s->s3->rbuf.left == 0) /* no read-ahead left? */
871 {
872 BIO *bio;
873 /* In the case where we try to read application data,
874 * but we trigger an SSL handshake, we return -1 with
875 * the retry option set. Otherwise renegotiation may
876 * cause nasty problems in the blocking world */
877 s->rwstate=SSL_READING;
878 bio=SSL_get_rbio(s);
879 BIO_clear_retry_flags(bio);
880 BIO_set_retry_read(bio);
881 return(-1);
882 }
883 }
884 }
885 }
886 /* we either finished a handshake or ignored the request,
887 * now try again to obtain the (application) data we were asked for */
888 goto start;
889 }
890
891 if (s->d1->alert_fragment_len >= DTLS1_AL_HEADER_LENGTH)
892 {
893 int alert_level = s->d1->alert_fragment[0];
894 int alert_descr = s->d1->alert_fragment[1];
895
896 s->d1->alert_fragment_len = 0;
897
898 if (s->msg_callback)
899 s->msg_callback(0, s->version, SSL3_RT_ALERT,
900 s->d1->alert_fragment, 2, s, s->msg_callback_arg);
901
902 if (s->info_callback != NULL)
903 cb=s->info_callback;
904 else if (s->ctx->info_callback != NULL)
905 cb=s->ctx->info_callback;
906
907 if (cb != NULL)
908 {
909 j = (alert_level << 8) | alert_descr;
910 cb(s, SSL_CB_READ_ALERT, j);
911 }
912
913 if (alert_level == 1) /* warning */
914 {
915 s->s3->warn_alert = alert_descr;
916 if (alert_descr == SSL_AD_CLOSE_NOTIFY)
917 {
918 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
919 return(0);
920 }
921#if 0
922 /* XXX: this is a possible improvement in the future */
923 /* now check if it's a missing record */
924 if (alert_descr == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE)
925 {
926 unsigned short seq;
927 unsigned int frag_off;
928 unsigned char *p = &(s->d1->alert_fragment[2]);
929
930 n2s(p, seq);
931 n2l3(p, frag_off);
932
933 dtls1_retransmit_message(s, seq, frag_off, &found);
934 if ( ! found && SSL_in_init(s))
935 {
936 /* fprintf( stderr,"in init = %d\n", SSL_in_init(s)); */
937 /* requested a message not yet sent,
938 send an alert ourselves */
939 ssl3_send_alert(s,SSL3_AL_WARNING,
940 DTLS1_AD_MISSING_HANDSHAKE_MESSAGE);
941 }
942 }
943#endif
944 }
945 else if (alert_level == 2) /* fatal */
946 {
947 char tmp[16];
948
949 s->rwstate=SSL_NOTHING;
950 s->s3->fatal_alert = alert_descr;
951 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
952 BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
953 ERR_add_error_data(2,"SSL alert number ",tmp);
954 s->shutdown|=SSL_RECEIVED_SHUTDOWN;
955 SSL_CTX_remove_session(s->ctx,s->session);
956 return(0);
957 }
958 else
959 {
960 al=SSL_AD_ILLEGAL_PARAMETER;
961 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
962 goto f_err;
963 }
964
965 goto start;
966 }
967
968 if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
969 {
970 s->rwstate=SSL_NOTHING;
971 rr->length=0;
972 return(0);
973 }
974
975 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
976 {
977 struct ccs_header_st ccs_hdr;
978
979 dtls1_get_ccs_header(rr->data, &ccs_hdr);
980
981 if ( ccs_hdr.seq == s->d1->handshake_read_seq)
982 {
983 /* 'Change Cipher Spec' is just a single byte, so we know
984 * exactly what the record payload has to look like */
985 /* XDTLS: check that epoch is consistent */
986 if ( (rr->length != DTLS1_CCS_HEADER_LENGTH) ||
987 (rr->off != 0) || (rr->data[0] != SSL3_MT_CCS))
988 {
989 i=SSL_AD_ILLEGAL_PARAMETER;
990 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
991 goto err;
992 }
993
994 rr->length=0;
995
996 if (s->msg_callback)
997 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC,
998 rr->data, 1, s, s->msg_callback_arg);
999
1000 s->s3->change_cipher_spec=1;
1001 if (!ssl3_do_change_cipher_spec(s))
1002 goto err;
1003
1004 /* do this whenever CCS is processed */
1005 dtls1_reset_seq_numbers(s, SSL3_CC_READ);
1006
1007 /* handshake read seq is reset upon handshake completion */
1008 s->d1->handshake_read_seq++;
1009
1010 goto start;
1011 }
1012 else
1013 {
1014 rr->length = 0;
1015 goto start;
1016 }
1017 }
1018
1019 /* Unexpected handshake message (Client Hello, or protocol violation) */
1020 if ((s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
1021 !s->in_handshake)
1022 {
1023 struct hm_header_st msg_hdr;
1024
1025 /* this may just be a stale retransmit */
1026 dtls1_get_message_header(rr->data, &msg_hdr);
1027 if( rr->epoch != s->d1->r_epoch)
1028 {
1029 rr->length = 0;
1030 goto start;
1031 }
1032
1033 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1034 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1035 {
1036#if 0 /* worked only because C operator preferences are not as expected (and
1037 * because this is not really needed for clients except for detecting
1038 * protocol violations): */
1039 s->state=SSL_ST_BEFORE|(s->server)
1040 ?SSL_ST_ACCEPT
1041 :SSL_ST_CONNECT;
1042#else
1043 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1044#endif
1045 s->new_session=1;
1046 }
1047 i=s->handshake_func(s);
1048 if (i < 0) return(i);
1049 if (i == 0)
1050 {
1051 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1052 return(-1);
1053 }
1054
1055 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1056 {
1057 if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1058 {
1059 BIO *bio;
1060 /* In the case where we try to read application data,
1061 * but we trigger an SSL handshake, we return -1 with
1062 * the retry option set. Otherwise renegotiation may
1063 * cause nasty problems in the blocking world */
1064 s->rwstate=SSL_READING;
1065 bio=SSL_get_rbio(s);
1066 BIO_clear_retry_flags(bio);
1067 BIO_set_retry_read(bio);
1068 return(-1);
1069 }
1070 }
1071 goto start;
1072 }
1073
1074 switch (rr->type)
1075 {
1076 default:
1077#ifndef OPENSSL_NO_TLS
1078 /* TLS just ignores unknown message types */
1079 if (s->version == TLS1_VERSION)
1080 {
1081 rr->length = 0;
1082 goto start;
1083 }
1084#endif
1085 al=SSL_AD_UNEXPECTED_MESSAGE;
1086 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1087 goto f_err;
1088 case SSL3_RT_CHANGE_CIPHER_SPEC:
1089 case SSL3_RT_ALERT:
1090 case SSL3_RT_HANDSHAKE:
1091 /* we already handled all of these, with the possible exception
1092 * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1093 * should not happen when type != rr->type */
1094 al=SSL_AD_UNEXPECTED_MESSAGE;
1095 SSLerr(SSL_F_DTLS1_READ_BYTES,ERR_R_INTERNAL_ERROR);
1096 goto f_err;
1097 case SSL3_RT_APPLICATION_DATA:
1098 /* At this point, we were expecting handshake data,
1099 * but have application data. If the library was
1100 * running inside ssl3_read() (i.e. in_read_app_data
1101 * is set) and it makes sense to read application data
1102 * at this point (session renegotiation not yet started),
1103 * we will indulge it.
1104 */
1105 if (s->s3->in_read_app_data &&
1106 (s->s3->total_renegotiations != 0) &&
1107 ((
1108 (s->state & SSL_ST_CONNECT) &&
1109 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1110 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1111 ) || (
1112 (s->state & SSL_ST_ACCEPT) &&
1113 (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1114 (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1115 )
1116 ))
1117 {
1118 s->s3->in_read_app_data=2;
1119 return(-1);
1120 }
1121 else
1122 {
1123 al=SSL_AD_UNEXPECTED_MESSAGE;
1124 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1125 goto f_err;
1126 }
1127 }
1128 /* not reached */
1129
1130f_err:
1131 ssl3_send_alert(s,SSL3_AL_FATAL,al);
1132err:
1133 return(-1);
1134 }
1135
1136int
1137dtls1_write_app_data_bytes(SSL *s, int type, const void *buf_, int len)
1138 {
1139 unsigned int n,tot;
1140 int i;
1141
1142 if (SSL_in_init(s) && !s->in_handshake)
1143 {
1144 i=s->handshake_func(s);
1145 if (i < 0) return(i);
1146 if (i == 0)
1147 {
1148 SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1149 return -1;
1150 }
1151 }
1152
1153 tot = s->s3->wnum;
1154 n = len - tot;
1155
1156 while( n)
1157 {
1158 /* dtls1_write_bytes sends one record at a time, sized according to
1159 * the currently known MTU */
1160 i = dtls1_write_bytes(s, type, buf_, len);
1161 if (i <= 0) return i;
1162
1163 if ((i == (int)n) ||
1164 (type == SSL3_RT_APPLICATION_DATA &&
1165 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
1166 {
1167 /* next chunk of data should get another prepended empty fragment
1168 * in ciphersuites with known-IV weakness: */
1169 s->s3->empty_fragment_done = 0;
1170 return tot+i;
1171 }
1172
1173 tot += i;
1174 n-=i;
1175 }
1176
1177 return tot;
1178 }
1179
1180
1181 /* this only happens when a client hello is received and a handshake
1182 * is started. */
1183static int
1184have_handshake_fragment(SSL *s, int type, unsigned char *buf,
1185 int len, int peek)
1186 {
1187
1188 if ((type == SSL3_RT_HANDSHAKE) && (s->d1->handshake_fragment_len > 0))
1189 /* (partially) satisfy request from storage */
1190 {
1191 unsigned char *src = s->d1->handshake_fragment;
1192 unsigned char *dst = buf;
1193 unsigned int k,n;
1194
1195 /* peek == 0 */
1196 n = 0;
1197 while ((len > 0) && (s->d1->handshake_fragment_len > 0))
1198 {
1199 *dst++ = *src++;
1200 len--; s->d1->handshake_fragment_len--;
1201 n++;
1202 }
1203 /* move any remaining fragment bytes: */
1204 for (k = 0; k < s->d1->handshake_fragment_len; k++)
1205 s->d1->handshake_fragment[k] = *src++;
1206 return n;
1207 }
1208
1209 return 0;
1210 }
1211
1212
1213
1214
1215/* Call this to write data in records of type 'type'
1216 * It will return <= 0 if not all data has been sent or non-blocking IO.
1217 */
1218int dtls1_write_bytes(SSL *s, int type, const void *buf_, int len)
1219 {
1220 const unsigned char *buf=buf_;
1221 unsigned int tot,n,nw;
1222 int i;
1223 unsigned int mtu;
1224
1225 s->rwstate=SSL_NOTHING;
1226 tot=s->s3->wnum;
1227
1228 n=(len-tot);
1229
1230 /* handshake layer figures out MTU for itself, but data records
1231 * are also sent through this interface, so need to figure out MTU */
1232#if 0
1233 mtu = BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_GET_MTU, 0, NULL);
1234 mtu += DTLS1_HM_HEADER_LENGTH; /* HM already inserted */
1235#endif
1236 mtu = s->d1->mtu;
1237
1238 if (mtu > SSL3_RT_MAX_PLAIN_LENGTH)
1239 mtu = SSL3_RT_MAX_PLAIN_LENGTH;
1240
1241 if (n > mtu)
1242 nw=mtu;
1243 else
1244 nw=n;
1245
1246 i=do_dtls1_write(s, type, &(buf[tot]), nw, 0);
1247 if (i <= 0)
1248 {
1249 s->s3->wnum=tot;
1250 return i;
1251 }
1252
1253 if ( (int)s->s3->wnum + i == len)
1254 s->s3->wnum = 0;
1255 else
1256 s->s3->wnum += i;
1257
1258 return tot + i;
1259 }
1260
1261int do_dtls1_write(SSL *s, int type, const unsigned char *buf, unsigned int len, int create_empty_fragment)
1262 {
1263 unsigned char *p,*pseq;
1264 int i,mac_size,clear=0;
1265 int prefix_len = 0;
1266 SSL3_RECORD *wr;
1267 SSL3_BUFFER *wb;
1268 SSL_SESSION *sess;
1269 int bs;
1270
1271 /* first check if there is a SSL3_BUFFER still being written
1272 * out. This will happen with non blocking IO */
1273 if (s->s3->wbuf.left != 0)
1274 {
1275 OPENSSL_assert(0); /* XDTLS: want to see if we ever get here */
1276 return(ssl3_write_pending(s,type,buf,len));
1277 }
1278
1279 /* If we have an alert to send, lets send it */
1280 if (s->s3->alert_dispatch)
1281 {
1282 i=s->method->ssl_dispatch_alert(s);
1283 if (i <= 0)
1284 return(i);
1285 /* if it went, fall through and send more stuff */
1286 }
1287
1288 if (len == 0 && !create_empty_fragment)
1289 return 0;
1290
1291 wr= &(s->s3->wrec);
1292 wb= &(s->s3->wbuf);
1293 sess=s->session;
1294
1295 if ( (sess == NULL) ||
1296 (s->enc_write_ctx == NULL) ||
1297 (s->write_hash == NULL))
1298 clear=1;
1299
1300 if (clear)
1301 mac_size=0;
1302 else
1303 mac_size=EVP_MD_size(s->write_hash);
1304
1305 /* DTLS implements explicit IV, so no need for empty fragments */
1306#if 0
1307 /* 'create_empty_fragment' is true only when this function calls itself */
1308 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done
1309 && SSL_version(s) != DTLS1_VERSION)
1310 {
1311 /* countermeasure against known-IV weakness in CBC ciphersuites
1312 * (see http://www.openssl.org/~bodo/tls-cbc.txt)
1313 */
1314
1315 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
1316 {
1317 /* recursive function call with 'create_empty_fragment' set;
1318 * this prepares and buffers the data for an empty fragment
1319 * (these 'prefix_len' bytes are sent out later
1320 * together with the actual payload) */
1321 prefix_len = s->method->do_ssl_write(s, type, buf, 0, 1);
1322 if (prefix_len <= 0)
1323 goto err;
1324
1325 if (s->s3->wbuf.len < (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE)
1326 {
1327 /* insufficient space */
1328 SSLerr(SSL_F_DO_DTLS1_WRITE, ERR_R_INTERNAL_ERROR);
1329 goto err;
1330 }
1331 }
1332
1333 s->s3->empty_fragment_done = 1;
1334 }
1335#endif
1336
1337 p = wb->buf + prefix_len;
1338
1339 /* write the header */
1340
1341 *(p++)=type&0xff;
1342 wr->type=type;
1343
1344 *(p++)=(s->version>>8);
1345 *(p++)=s->version&0xff;
1346
1347 /* field where we are to write out packet epoch, seq num and len */
1348 pseq=p;
1349 p+=10;
1350
1351 /* lets setup the record stuff. */
1352
1353 /* Make space for the explicit IV in case of CBC.
1354 * (this is a bit of a boundary violation, but what the heck).
1355 */
1356 if ( s->enc_write_ctx &&
1357 (EVP_CIPHER_mode( s->enc_write_ctx->cipher ) & EVP_CIPH_CBC_MODE))
1358 bs = EVP_CIPHER_block_size(s->enc_write_ctx->cipher);
1359 else
1360 bs = 0;
1361
1362 wr->data=p + bs; /* make room for IV in case of CBC */
1363 wr->length=(int)len;
1364 wr->input=(unsigned char *)buf;
1365
1366 /* we now 'read' from wr->input, wr->length bytes into
1367 * wr->data */
1368
1369 /* first we compress */
1370 if (s->compress != NULL)
1371 {
1372 if (!ssl3_do_compress(s))
1373 {
1374 SSLerr(SSL_F_DO_DTLS1_WRITE,SSL_R_COMPRESSION_FAILURE);
1375 goto err;
1376 }
1377 }
1378 else
1379 {
1380 memcpy(wr->data,wr->input,wr->length);
1381 wr->input=wr->data;
1382 }
1383
1384 /* we should still have the output to wr->data and the input
1385 * from wr->input. Length should be wr->length.
1386 * wr->data still points in the wb->buf */
1387
1388 if (mac_size != 0)
1389 {
1390 s->method->ssl3_enc->mac(s,&(p[wr->length + bs]),1);
1391 wr->length+=mac_size;
1392 }
1393
1394 /* this is true regardless of mac size */
1395 wr->input=p;
1396 wr->data=p;
1397
1398
1399 /* ssl3_enc can only have an error on read */
1400 wr->length += bs; /* bs != 0 in case of CBC. The enc fn provides
1401 * the randomness */
1402 s->method->ssl3_enc->enc(s,1);
1403
1404 /* record length after mac and block padding */
1405/* if (type == SSL3_RT_APPLICATION_DATA ||
1406 (type == SSL3_RT_ALERT && ! SSL_in_init(s))) */
1407
1408 /* there's only one epoch between handshake and app data */
1409
1410 s2n(s->d1->w_epoch, pseq);
1411
1412 /* XDTLS: ?? */
1413/* else
1414 s2n(s->d1->handshake_epoch, pseq); */
1415
1416 memcpy(pseq, &(s->s3->write_sequence[2]), 6);
1417 pseq+=6;
1418 s2n(wr->length,pseq);
1419
1420 /* we should now have
1421 * wr->data pointing to the encrypted data, which is
1422 * wr->length long */
1423 wr->type=type; /* not needed but helps for debugging */
1424 wr->length+=DTLS1_RT_HEADER_LENGTH;
1425
1426#if 0 /* this is now done at the message layer */
1427 /* buffer the record, making it easy to handle retransmits */
1428 if ( type == SSL3_RT_HANDSHAKE || type == SSL3_RT_CHANGE_CIPHER_SPEC)
1429 dtls1_buffer_record(s, wr->data, wr->length,
1430 *((PQ_64BIT *)&(s->s3->write_sequence[0])));
1431#endif
1432
1433 ssl3_record_sequence_update(&(s->s3->write_sequence[0]));
1434
1435 if (create_empty_fragment)
1436 {
1437 /* we are in a recursive call;
1438 * just return the length, don't write out anything here
1439 */
1440 return wr->length;
1441 }
1442
1443 /* now let's set up wb */
1444 wb->left = prefix_len + wr->length;
1445 wb->offset = 0;
1446
1447 /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
1448 s->s3->wpend_tot=len;
1449 s->s3->wpend_buf=buf;
1450 s->s3->wpend_type=type;
1451 s->s3->wpend_ret=len;
1452
1453 /* we now just need to write the buffer */
1454 return ssl3_write_pending(s,type,buf,len);
1455err:
1456 return -1;
1457 }
1458
1459
1460
1461static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap,
1462 PQ_64BIT *seq_num)
1463 {
1464#if PQ_64BIT_IS_INTEGER
1465 PQ_64BIT mask = 0x0000000000000001L;
1466#endif
1467 PQ_64BIT rcd_num, tmp;
1468
1469 pq_64bit_init(&rcd_num);
1470 pq_64bit_init(&tmp);
1471
1472 /* this is the sequence number for the record just read */
1473 pq_64bit_bin2num(&rcd_num, s->s3->read_sequence, 8);
1474
1475
1476 if (pq_64bit_gt(&rcd_num, &(bitmap->max_seq_num)) ||
1477 pq_64bit_eq(&rcd_num, &(bitmap->max_seq_num)))
1478 {
1479 pq_64bit_assign(seq_num, &rcd_num);
1480 pq_64bit_free(&rcd_num);
1481 pq_64bit_free(&tmp);
1482 return 1; /* this record is new */
1483 }
1484
1485 pq_64bit_sub(&tmp, &(bitmap->max_seq_num), &rcd_num);
1486
1487 if ( pq_64bit_get_word(&tmp) > bitmap->length)
1488 {
1489 pq_64bit_free(&rcd_num);
1490 pq_64bit_free(&tmp);
1491 return 0; /* stale, outside the window */
1492 }
1493
1494#if PQ_64BIT_IS_BIGNUM
1495 {
1496 int offset;
1497 pq_64bit_sub(&tmp, &(bitmap->max_seq_num), &rcd_num);
1498 pq_64bit_sub_word(&tmp, 1);
1499 offset = pq_64bit_get_word(&tmp);
1500 if ( pq_64bit_is_bit_set(&(bitmap->map), offset))
1501 {
1502 pq_64bit_free(&rcd_num);
1503 pq_64bit_free(&tmp);
1504 return 0;
1505 }
1506 }
1507#else
1508 mask <<= (bitmap->max_seq_num - rcd_num - 1);
1509 if (bitmap->map & mask)
1510 return 0; /* record previously received */
1511#endif
1512
1513 pq_64bit_assign(seq_num, &rcd_num);
1514 pq_64bit_free(&rcd_num);
1515 pq_64bit_free(&tmp);
1516 return 1;
1517 }
1518
1519
1520static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap)
1521 {
1522 unsigned int shift;
1523 PQ_64BIT rcd_num;
1524 PQ_64BIT tmp;
1525 PQ_64BIT_CTX *ctx;
1526
1527 pq_64bit_init(&rcd_num);
1528 pq_64bit_init(&tmp);
1529
1530 pq_64bit_bin2num(&rcd_num, s->s3->read_sequence, 8);
1531
1532 /* unfortunate code complexity due to 64-bit manipulation support
1533 * on 32-bit machines */
1534 if ( pq_64bit_gt(&rcd_num, &(bitmap->max_seq_num)) ||
1535 pq_64bit_eq(&rcd_num, &(bitmap->max_seq_num)))
1536 {
1537 pq_64bit_sub(&tmp, &rcd_num, &(bitmap->max_seq_num));
1538 pq_64bit_add_word(&tmp, 1);
1539
1540 shift = (unsigned int)pq_64bit_get_word(&tmp);
1541
1542 pq_64bit_lshift(&(tmp), &(bitmap->map), shift);
1543 pq_64bit_assign(&(bitmap->map), &tmp);
1544
1545 pq_64bit_set_bit(&(bitmap->map), 0);
1546 pq_64bit_add_word(&rcd_num, 1);
1547 pq_64bit_assign(&(bitmap->max_seq_num), &rcd_num);
1548
1549 pq_64bit_assign_word(&tmp, 1);
1550 pq_64bit_lshift(&tmp, &tmp, bitmap->length);
1551 ctx = pq_64bit_ctx_new(&ctx);
1552 pq_64bit_mod(&(bitmap->map), &(bitmap->map), &tmp, ctx);
1553 pq_64bit_ctx_free(ctx);
1554 }
1555 else
1556 {
1557 pq_64bit_sub(&tmp, &(bitmap->max_seq_num), &rcd_num);
1558 pq_64bit_sub_word(&tmp, 1);
1559 shift = (unsigned int)pq_64bit_get_word(&tmp);
1560
1561 pq_64bit_set_bit(&(bitmap->map), shift);
1562 }
1563
1564 pq_64bit_free(&rcd_num);
1565 pq_64bit_free(&tmp);
1566 }
1567
1568
1569int dtls1_dispatch_alert(SSL *s)
1570 {
1571 int i,j;
1572 void (*cb)(const SSL *ssl,int type,int val)=NULL;
1573 unsigned char buf[2 + 2 + 3]; /* alert level + alert desc + message seq +frag_off */
1574 unsigned char *ptr = &buf[0];
1575
1576 s->s3->alert_dispatch=0;
1577
1578 memset(buf, 0x00, sizeof(buf));
1579 *ptr++ = s->s3->send_alert[0];
1580 *ptr++ = s->s3->send_alert[1];
1581
1582 if (s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE)
1583 {
1584 s2n(s->d1->handshake_read_seq, ptr);
1585#if 0
1586 if ( s->d1->r_msg_hdr.frag_off == 0) /* waiting for a new msg */
1587
1588 else
1589 s2n(s->d1->r_msg_hdr.seq, ptr); /* partial msg read */
1590#endif
1591
1592#if 0
1593 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);
1594#endif
1595 l2n3(s->d1->r_msg_hdr.frag_off, ptr);
1596 }
1597
1598 i = do_dtls1_write(s, SSL3_RT_ALERT, &buf[0], sizeof(buf), 0);
1599 if (i <= 0)
1600 {
1601 s->s3->alert_dispatch=1;
1602 /* fprintf( stderr, "not done with alert\n" ); */
1603 }
1604 else
1605 {
1606 if ( s->s3->send_alert[0] == SSL3_AL_FATAL ||
1607 s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE)
1608 (void)BIO_flush(s->wbio);
1609
1610 if (s->msg_callback)
1611 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert,
1612 2, s, s->msg_callback_arg);
1613
1614 if (s->info_callback != NULL)
1615 cb=s->info_callback;
1616 else if (s->ctx->info_callback != NULL)
1617 cb=s->ctx->info_callback;
1618
1619 if (cb != NULL)
1620 {
1621 j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1622 cb(s,SSL_CB_WRITE_ALERT,j);
1623 }
1624 }
1625 return(i);
1626 }
1627
1628
1629static DTLS1_BITMAP *
1630dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr, unsigned int *is_next_epoch)
1631 {
1632
1633 *is_next_epoch = 0;
1634
1635 /* In current epoch, accept HM, CCS, DATA, & ALERT */
1636 if (rr->epoch == s->d1->r_epoch)
1637 return &s->d1->bitmap;
1638
1639 /* Only HM and ALERT messages can be from the next epoch */
1640 else if (rr->epoch == (unsigned long)(s->d1->r_epoch + 1) &&
1641 (rr->type == SSL3_RT_HANDSHAKE ||
1642 rr->type == SSL3_RT_ALERT))
1643 {
1644 *is_next_epoch = 1;
1645 return &s->d1->next_bitmap;
1646 }
1647
1648 return NULL;
1649 }
1650
1651#if 0
1652static int
1653dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr, unsigned short *priority,
1654 unsigned long *offset)
1655 {
1656
1657 /* alerts are passed up immediately */
1658 if ( rr->type == SSL3_RT_APPLICATION_DATA ||
1659 rr->type == SSL3_RT_ALERT)
1660 return 0;
1661
1662 /* Only need to buffer if a handshake is underway.
1663 * (this implies that Hello Request and Client Hello are passed up
1664 * immediately) */
1665 if ( SSL_in_init(s))
1666 {
1667 unsigned char *data = rr->data;
1668 /* need to extract the HM/CCS sequence number here */
1669 if ( rr->type == SSL3_RT_HANDSHAKE ||
1670 rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1671 {
1672 unsigned short seq_num;
1673 struct hm_header_st msg_hdr;
1674 struct ccs_header_st ccs_hdr;
1675
1676 if ( rr->type == SSL3_RT_HANDSHAKE)
1677 {
1678 dtls1_get_message_header(data, &msg_hdr);
1679 seq_num = msg_hdr.seq;
1680 *offset = msg_hdr.frag_off;
1681 }
1682 else
1683 {
1684 dtls1_get_ccs_header(data, &ccs_hdr);
1685 seq_num = ccs_hdr.seq;
1686 *offset = 0;
1687 }
1688
1689 /* this is either a record we're waiting for, or a
1690 * retransmit of something we happened to previously
1691 * receive (higher layers will drop the repeat silently */
1692 if ( seq_num < s->d1->handshake_read_seq)
1693 return 0;
1694 if (rr->type == SSL3_RT_HANDSHAKE &&
1695 seq_num == s->d1->handshake_read_seq &&
1696 msg_hdr.frag_off < s->d1->r_msg_hdr.frag_off)
1697 return 0;
1698 else if ( seq_num == s->d1->handshake_read_seq &&
1699 (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC ||
1700 msg_hdr.frag_off == s->d1->r_msg_hdr.frag_off))
1701 return 0;
1702 else
1703 {
1704 *priority = seq_num;
1705 return 1;
1706 }
1707 }
1708 else /* unknown record type */
1709 return 0;
1710 }
1711
1712 return 0;
1713 }
1714#endif
1715
1716void
1717dtls1_reset_seq_numbers(SSL *s, int rw)
1718 {
1719 unsigned char *seq;
1720 unsigned int seq_bytes = sizeof(s->s3->read_sequence);
1721
1722 if ( rw & SSL3_CC_READ)
1723 {
1724 seq = s->s3->read_sequence;
1725 s->d1->r_epoch++;
1726
1727 pq_64bit_assign(&(s->d1->bitmap.map), &(s->d1->next_bitmap.map));
1728 s->d1->bitmap.length = s->d1->next_bitmap.length;
1729 pq_64bit_assign(&(s->d1->bitmap.max_seq_num),
1730 &(s->d1->next_bitmap.max_seq_num));
1731
1732 pq_64bit_free(&(s->d1->next_bitmap.map));
1733 pq_64bit_free(&(s->d1->next_bitmap.max_seq_num));
1734 memset(&(s->d1->next_bitmap), 0x00, sizeof(DTLS1_BITMAP));
1735 pq_64bit_init(&(s->d1->next_bitmap.map));
1736 pq_64bit_init(&(s->d1->next_bitmap.max_seq_num));
1737 }
1738 else
1739 {
1740 seq = s->s3->write_sequence;
1741 s->d1->w_epoch++;
1742 }
1743
1744 memset(seq, 0x00, seq_bytes);
1745 }
1746
1747#if PQ_64BIT_IS_INTEGER
1748static PQ_64BIT
1749bytes_to_long_long(unsigned char *bytes, PQ_64BIT *num)
1750 {
1751 PQ_64BIT _num;
1752
1753 _num = (((PQ_64BIT)bytes[0]) << 56) |
1754 (((PQ_64BIT)bytes[1]) << 48) |
1755 (((PQ_64BIT)bytes[2]) << 40) |
1756 (((PQ_64BIT)bytes[3]) << 32) |
1757 (((PQ_64BIT)bytes[4]) << 24) |
1758 (((PQ_64BIT)bytes[5]) << 16) |
1759 (((PQ_64BIT)bytes[6]) << 8) |
1760 (((PQ_64BIT)bytes[7]) );
1761
1762 *num = _num ;
1763 return _num;
1764 }
1765#endif
1766
1767
1768static void
1769dtls1_clear_timeouts(SSL *s)
1770 {
1771 memset(&(s->d1->timeout), 0x00, sizeof(struct dtls1_timeout_st));
1772 }