1/*
2 * Copyright 2005-2018 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10#include <stdio.h>
11#include <errno.h>
12#include "../ssl_local.h"
13#include <openssl/evp.h>
14#include <openssl/buffer.h>
15#include "record_local.h"
16#include "internal/packet.h"
17#include "internal/cryptlib.h"
18
19int DTLS_RECORD_LAYER_new(RECORD_LAYER *rl)
20{
21 DTLS_RECORD_LAYER *d;
22
23 if ((d = OPENSSL_malloc(sizeof(*d))) == NULL) {
24 SSLerr(SSL_F_DTLS_RECORD_LAYER_NEW, ERR_R_MALLOC_FAILURE);
25 return 0;
26 }
27
28 rl->d = d;
29
30 d->unprocessed_rcds.q = pqueue_new();
31 d->processed_rcds.q = pqueue_new();
32 d->buffered_app_data.q = pqueue_new();
33
34 if (d->unprocessed_rcds.q == NULL || d->processed_rcds.q == NULL
35 || d->buffered_app_data.q == NULL) {
36 pqueue_free(d->unprocessed_rcds.q);
37 pqueue_free(d->processed_rcds.q);
38 pqueue_free(d->buffered_app_data.q);
39 OPENSSL_free(d);
40 rl->d = NULL;
41 return 0;
42 }
43
44 return 1;
45}
46
47void DTLS_RECORD_LAYER_free(RECORD_LAYER *rl)
48{
49 DTLS_RECORD_LAYER_clear(rl);
50 pqueue_free(rl->d->unprocessed_rcds.q);
51 pqueue_free(rl->d->processed_rcds.q);
52 pqueue_free(rl->d->buffered_app_data.q);
53 OPENSSL_free(rl->d);
54 rl->d = NULL;
55}
56
57void DTLS_RECORD_LAYER_clear(RECORD_LAYER *rl)
58{
59 DTLS_RECORD_LAYER *d;
60 pitem *item = NULL;
61 DTLS1_RECORD_DATA *rdata;
62 pqueue *unprocessed_rcds;
63 pqueue *processed_rcds;
64 pqueue *buffered_app_data;
65
66 d = rl->d;
67
68 while ((item = pqueue_pop(d->unprocessed_rcds.q)) != NULL) {
69 rdata = (DTLS1_RECORD_DATA *)item->data;
70 OPENSSL_free(rdata->rbuf.buf);
71 OPENSSL_free(item->data);
72 pitem_free(item);
73 }
74
75 while ((item = pqueue_pop(d->processed_rcds.q)) != NULL) {
76 rdata = (DTLS1_RECORD_DATA *)item->data;
77 OPENSSL_free(rdata->rbuf.buf);
78 OPENSSL_free(item->data);
79 pitem_free(item);
80 }
81
82 while ((item = pqueue_pop(d->buffered_app_data.q)) != NULL) {
83 rdata = (DTLS1_RECORD_DATA *)item->data;
84 OPENSSL_free(rdata->rbuf.buf);
85 OPENSSL_free(item->data);
86 pitem_free(item);
87 }
88
89 unprocessed_rcds = d->unprocessed_rcds.q;
90 processed_rcds = d->processed_rcds.q;
91 buffered_app_data = d->buffered_app_data.q;
92 memset(d, 0, sizeof(*d));
93 d->unprocessed_rcds.q = unprocessed_rcds;
94 d->processed_rcds.q = processed_rcds;
95 d->buffered_app_data.q = buffered_app_data;
96}
97
98void DTLS_RECORD_LAYER_set_saved_w_epoch(RECORD_LAYER *rl, unsigned short e)
99{
100 if (e == rl->d->w_epoch - 1) {
101 memcpy(rl->d->curr_write_sequence,
102 rl->write_sequence, sizeof(rl->write_sequence));
103 memcpy(rl->write_sequence,
104 rl->d->last_write_sequence, sizeof(rl->write_sequence));
105 } else if (e == rl->d->w_epoch + 1) {
106 memcpy(rl->d->last_write_sequence,
107 rl->write_sequence, sizeof(unsigned char[8]));
108 memcpy(rl->write_sequence,
109 rl->d->curr_write_sequence, sizeof(rl->write_sequence));
110 }
111 rl->d->w_epoch = e;
112}
113
114void DTLS_RECORD_LAYER_set_write_sequence(RECORD_LAYER *rl, unsigned char *seq)
115{
116 memcpy(rl->write_sequence, seq, SEQ_NUM_SIZE);
117}
118
119/* copy buffered record into SSL structure */
120static int dtls1_copy_record(SSL *s, pitem *item)
121{
122 DTLS1_RECORD_DATA *rdata;
123
124 rdata = (DTLS1_RECORD_DATA *)item->data;
125
126 SSL3_BUFFER_release(&s->rlayer.rbuf);
127
128 s->rlayer.packet = rdata->packet;
129 s->rlayer.packet_length = rdata->packet_length;
130 memcpy(&s->rlayer.rbuf, &(rdata->rbuf), sizeof(SSL3_BUFFER));
131 memcpy(&s->rlayer.rrec, &(rdata->rrec), sizeof(SSL3_RECORD));
132
133 /* Set proper sequence number for mac calculation */
134 memcpy(&(s->rlayer.read_sequence[2]), &(rdata->packet[5]), 6);
135
136 return 1;
137}
138
139int dtls1_buffer_record(SSL *s, record_pqueue *queue, unsigned char *priority)
140{
141 DTLS1_RECORD_DATA *rdata;
142 pitem *item;
143
144 /* Limit the size of the queue to prevent DOS attacks */
145 if (pqueue_size(queue->q) >= 100)
146 return 0;
147
148 rdata = OPENSSL_malloc(sizeof(*rdata));
149 item = pitem_new(priority, rdata);
150 if (rdata == NULL || item == NULL) {
151 OPENSSL_free(rdata);
152 pitem_free(item);
153 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DTLS1_BUFFER_RECORD,
154 ERR_R_INTERNAL_ERROR);
155 return -1;
156 }
157
158 rdata->packet = s->rlayer.packet;
159 rdata->packet_length = s->rlayer.packet_length;
160 memcpy(&(rdata->rbuf), &s->rlayer.rbuf, sizeof(SSL3_BUFFER));
161 memcpy(&(rdata->rrec), &s->rlayer.rrec, sizeof(SSL3_RECORD));
162
163 item->data = rdata;
164
165#ifndef OPENSSL_NO_SCTP
166 /* Store bio_dgram_sctp_rcvinfo struct */
167 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
168 (SSL_get_state(s) == TLS_ST_SR_FINISHED
169 || SSL_get_state(s) == TLS_ST_CR_FINISHED)) {
170 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_GET_RCVINFO,
171 sizeof(rdata->recordinfo), &rdata->recordinfo);
172 }
173#endif
174
175 s->rlayer.packet = NULL;
176 s->rlayer.packet_length = 0;
177 memset(&s->rlayer.rbuf, 0, sizeof(s->rlayer.rbuf));
178 memset(&s->rlayer.rrec, 0, sizeof(s->rlayer.rrec));
179
180 if (!ssl3_setup_buffers(s)) {
181 /* SSLfatal() already called */
182 OPENSSL_free(rdata->rbuf.buf);
183 OPENSSL_free(rdata);
184 pitem_free(item);
185 return -1;
186 }
187
188 if (pqueue_insert(queue->q, item) == NULL) {
189 /* Must be a duplicate so ignore it */
190 OPENSSL_free(rdata->rbuf.buf);
191 OPENSSL_free(rdata);
192 pitem_free(item);
193 }
194
195 return 1;
196}
197
198int dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue)
199{
200 pitem *item;
201
202 item = pqueue_pop(queue->q);
203 if (item) {
204 dtls1_copy_record(s, item);
205
206 OPENSSL_free(item->data);
207 pitem_free(item);
208
209 return 1;
210 }
211
212 return 0;
213}
214
215/*
216 * retrieve a buffered record that belongs to the new epoch, i.e., not
217 * processed yet
218 */
219#define dtls1_get_unprocessed_record(s) \
220 dtls1_retrieve_buffered_record((s), \
221 &((s)->rlayer.d->unprocessed_rcds))
222
223int dtls1_process_buffered_records(SSL *s)
224{
225 pitem *item;
226 SSL3_BUFFER *rb;
227 SSL3_RECORD *rr;
228 DTLS1_BITMAP *bitmap;
229 unsigned int is_next_epoch;
230 int replayok = 1;
231
232 item = pqueue_peek(s->rlayer.d->unprocessed_rcds.q);
233 if (item) {
234 /* Check if epoch is current. */
235 if (s->rlayer.d->unprocessed_rcds.epoch != s->rlayer.d->r_epoch)
236 return 1; /* Nothing to do. */
237
238 rr = RECORD_LAYER_get_rrec(&s->rlayer);
239
240 rb = RECORD_LAYER_get_rbuf(&s->rlayer);
241
242 if (SSL3_BUFFER_get_left(rb) > 0) {
243 /*
244 * We've still got data from the current packet to read. There could
245 * be a record from the new epoch in it - so don't overwrite it
246 * with the unprocessed records yet (we'll do it when we've
247 * finished reading the current packet).
248 */
249 return 1;
250 }
251
252 /* Process all the records. */
253 while (pqueue_peek(s->rlayer.d->unprocessed_rcds.q)) {
254 dtls1_get_unprocessed_record(s);
255 bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch);
256 if (bitmap == NULL) {
257 /*
258 * Should not happen. This will only ever be NULL when the
259 * current record is from a different epoch. But that cannot
260 * be the case because we already checked the epoch above
261 */
262 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
263 SSL_F_DTLS1_PROCESS_BUFFERED_RECORDS,
264 ERR_R_INTERNAL_ERROR);
265 return 0;
266 }
267#ifndef OPENSSL_NO_SCTP
268 /* Only do replay check if no SCTP bio */
269 if (!BIO_dgram_is_sctp(SSL_get_rbio(s)))
270#endif
271 {
272 /*
273 * Check whether this is a repeat, or aged record. We did this
274 * check once already when we first received the record - but
275 * we might have updated the window since then due to
276 * records we subsequently processed.
277 */
278 replayok = dtls1_record_replay_check(s, bitmap);
279 }
280
281 if (!replayok || !dtls1_process_record(s, bitmap)) {
282 if (ossl_statem_in_error(s)) {
283 /* dtls1_process_record called SSLfatal() */
284 return -1;
285 }
286 /* dump this record */
287 rr->length = 0;
288 RECORD_LAYER_reset_packet_length(&s->rlayer);
289 continue;
290 }
291
292 if (dtls1_buffer_record(s, &(s->rlayer.d->processed_rcds),
293 SSL3_RECORD_get_seq_num(s->rlayer.rrec)) < 0) {
294 /* SSLfatal() already called */
295 return 0;
296 }
297 }
298 }
299
300 /*
301 * sync epoch numbers once all the unprocessed records have been
302 * processed
303 */
304 s->rlayer.d->processed_rcds.epoch = s->rlayer.d->r_epoch;
305 s->rlayer.d->unprocessed_rcds.epoch = s->rlayer.d->r_epoch + 1;
306
307 return 1;
308}
309
310/*-
311 * Return up to 'len' payload bytes received in 'type' records.
312 * 'type' is one of the following:
313 *
314 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
315 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
316 * - 0 (during a shutdown, no data has to be returned)
317 *
318 * If we don't have stored data to work from, read a SSL/TLS record first
319 * (possibly multiple records if we still don't have anything to return).
320 *
321 * This function must handle any surprises the peer may have for us, such as
322 * Alert records (e.g. close_notify) or renegotiation requests. ChangeCipherSpec
323 * messages are treated as if they were handshake messages *if* the |recd_type|
324 * argument is non NULL.
325 * Also if record payloads contain fragments too small to process, we store
326 * them until there is enough for the respective protocol (the record protocol
327 * may use arbitrary fragmentation and even interleaving):
328 * Change cipher spec protocol
329 * just 1 byte needed, no need for keeping anything stored
330 * Alert protocol
331 * 2 bytes needed (AlertLevel, AlertDescription)
332 * Handshake protocol
333 * 4 bytes needed (HandshakeType, uint24 length) -- we just have
334 * to detect unexpected Client Hello and Hello Request messages
335 * here, anything else is handled by higher layers
336 * Application data protocol
337 * none of our business
338 */
339int dtls1_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf,
340 size_t len, int peek, size_t *readbytes)
341{
342 int i, j, iret;
343 size_t n;
344 SSL3_RECORD *rr;
345 void (*cb) (const SSL *ssl, int type2, int val) = NULL;
346
347 if (!SSL3_BUFFER_is_initialised(&s->rlayer.rbuf)) {
348 /* Not initialized yet */
349 if (!ssl3_setup_buffers(s)) {
350 /* SSLfatal() already called */
351 return -1;
352 }
353 }
354
355 if ((type && (type != SSL3_RT_APPLICATION_DATA) &&
356 (type != SSL3_RT_HANDSHAKE)) ||
357 (peek && (type != SSL3_RT_APPLICATION_DATA))) {
358 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DTLS1_READ_BYTES,
359 ERR_R_INTERNAL_ERROR);
360 return -1;
361 }
362
363 if (!ossl_statem_get_in_handshake(s) && SSL_in_init(s)) {
364 /* type == SSL3_RT_APPLICATION_DATA */
365 i = s->handshake_func(s);
366 /* SSLfatal() already called if appropriate */
367 if (i < 0)
368 return i;
369 if (i == 0)
370 return -1;
371 }
372
373 start:
374 s->rwstate = SSL_NOTHING;
375
376 /*-
377 * s->s3.rrec.type - is the type of record
378 * s->s3.rrec.data, - data
379 * s->s3.rrec.off, - offset into 'data' for next read
380 * s->s3.rrec.length, - number of bytes.
381 */
382 rr = s->rlayer.rrec;
383
384 /*
385 * We are not handshaking and have no data yet, so process data buffered
386 * during the last handshake in advance, if any.
387 */
388 if (SSL_is_init_finished(s) && SSL3_RECORD_get_length(rr) == 0) {
389 pitem *item;
390 item = pqueue_pop(s->rlayer.d->buffered_app_data.q);
391 if (item) {
392#ifndef OPENSSL_NO_SCTP
393 /* Restore bio_dgram_sctp_rcvinfo struct */
394 if (BIO_dgram_is_sctp(SSL_get_rbio(s))) {
395 DTLS1_RECORD_DATA *rdata = (DTLS1_RECORD_DATA *)item->data;
396 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_SET_RCVINFO,
397 sizeof(rdata->recordinfo), &rdata->recordinfo);
398 }
399#endif
400
401 dtls1_copy_record(s, item);
402
403 OPENSSL_free(item->data);
404 pitem_free(item);
405 }
406 }
407
408 /* Check for timeout */
409 if (dtls1_handle_timeout(s) > 0) {
410 goto start;
411 } else if (ossl_statem_in_error(s)) {
412 /* dtls1_handle_timeout() has failed with a fatal error */
413 return -1;
414 }
415
416 /* get new packet if necessary */
417 if ((SSL3_RECORD_get_length(rr) == 0)
418 || (s->rlayer.rstate == SSL_ST_READ_BODY)) {
419 RECORD_LAYER_set_numrpipes(&s->rlayer, 0);
420 iret = dtls1_get_record(s);
421 if (iret <= 0) {
422 iret = dtls1_read_failed(s, iret);
423 /*
424 * Anything other than a timeout is an error. SSLfatal() already
425 * called if appropriate.
426 */
427 if (iret <= 0)
428 return iret;
429 else
430 goto start;
431 }
432 RECORD_LAYER_set_numrpipes(&s->rlayer, 1);
433 }
434
435 /*
436 * Reset the count of consecutive warning alerts if we've got a non-empty
437 * record that isn't an alert.
438 */
439 if (SSL3_RECORD_get_type(rr) != SSL3_RT_ALERT
440 && SSL3_RECORD_get_length(rr) != 0)
441 s->rlayer.alert_count = 0;
442
443 /* we now have a packet which can be read and processed */
444
445 if (s->s3.change_cipher_spec /* set when we receive ChangeCipherSpec,
446 * reset by ssl3_get_finished */
447 && (SSL3_RECORD_get_type(rr) != SSL3_RT_HANDSHAKE)) {
448 /*
449 * We now have application data between CCS and Finished. Most likely
450 * the packets were reordered on their way, so buffer the application
451 * data for later processing rather than dropping the connection.
452 */
453 if (dtls1_buffer_record(s, &(s->rlayer.d->buffered_app_data),
454 SSL3_RECORD_get_seq_num(rr)) < 0) {
455 /* SSLfatal() already called */
456 return -1;
457 }
458 SSL3_RECORD_set_length(rr, 0);
459 SSL3_RECORD_set_read(rr);
460 goto start;
461 }
462
463 /*
464 * If the other end has shut down, throw anything we read away (even in
465 * 'peek' mode)
466 */
467 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) {
468 SSL3_RECORD_set_length(rr, 0);
469 SSL3_RECORD_set_read(rr);
470 s->rwstate = SSL_NOTHING;
471 return 0;
472 }
473
474 if (type == SSL3_RECORD_get_type(rr)
475 || (SSL3_RECORD_get_type(rr) == SSL3_RT_CHANGE_CIPHER_SPEC
476 && type == SSL3_RT_HANDSHAKE && recvd_type != NULL)) {
477 /*
478 * SSL3_RT_APPLICATION_DATA or
479 * SSL3_RT_HANDSHAKE or
480 * SSL3_RT_CHANGE_CIPHER_SPEC
481 */
482 /*
483 * make sure that we are not getting application data when we are
484 * doing a handshake for the first time
485 */
486 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
487 (s->enc_read_ctx == NULL)) {
488 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_F_DTLS1_READ_BYTES,
489 SSL_R_APP_DATA_IN_HANDSHAKE);
490 return -1;
491 }
492
493 if (recvd_type != NULL)
494 *recvd_type = SSL3_RECORD_get_type(rr);
495
496 if (len == 0) {
497 /*
498 * Mark a zero length record as read. This ensures multiple calls to
499 * SSL_read() with a zero length buffer will eventually cause
500 * SSL_pending() to report data as being available.
501 */
502 if (SSL3_RECORD_get_length(rr) == 0)
503 SSL3_RECORD_set_read(rr);
504 return 0;
505 }
506
507 if (len > SSL3_RECORD_get_length(rr))
508 n = SSL3_RECORD_get_length(rr);
509 else
510 n = len;
511
512 memcpy(buf, &(SSL3_RECORD_get_data(rr)[SSL3_RECORD_get_off(rr)]), n);
513 if (peek) {
514 if (SSL3_RECORD_get_length(rr) == 0)
515 SSL3_RECORD_set_read(rr);
516 } else {
517 SSL3_RECORD_sub_length(rr, n);
518 SSL3_RECORD_add_off(rr, n);
519 if (SSL3_RECORD_get_length(rr) == 0) {
520 s->rlayer.rstate = SSL_ST_READ_HEADER;
521 SSL3_RECORD_set_off(rr, 0);
522 SSL3_RECORD_set_read(rr);
523 }
524 }
525#ifndef OPENSSL_NO_SCTP
526 /*
527 * We might had to delay a close_notify alert because of reordered
528 * app data. If there was an alert and there is no message to read
529 * anymore, finally set shutdown.
530 */
531 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
532 s->d1->shutdown_received
533 && !BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) {
534 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
535 return 0;
536 }
537#endif
538 *readbytes = n;
539 return 1;
540 }
541
542 /*
543 * If we get here, then type != rr->type; if we have a handshake message,
544 * then it was unexpected (Hello Request or Client Hello).
545 */
546
547 if (SSL3_RECORD_get_type(rr) == SSL3_RT_ALERT) {
548 unsigned int alert_level, alert_descr;
549 unsigned char *alert_bytes = SSL3_RECORD_get_data(rr)
550 + SSL3_RECORD_get_off(rr);
551 PACKET alert;
552
553 if (!PACKET_buf_init(&alert, alert_bytes, SSL3_RECORD_get_length(rr))
554 || !PACKET_get_1(&alert, &alert_level)
555 || !PACKET_get_1(&alert, &alert_descr)
556 || PACKET_remaining(&alert) != 0) {
557 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_F_DTLS1_READ_BYTES,
558 SSL_R_INVALID_ALERT);
559 return -1;
560 }
561
562 if (s->msg_callback)
563 s->msg_callback(0, s->version, SSL3_RT_ALERT, alert_bytes, 2, s,
564 s->msg_callback_arg);
565
566 if (s->info_callback != NULL)
567 cb = s->info_callback;
568 else if (s->ctx->info_callback != NULL)
569 cb = s->ctx->info_callback;
570
571 if (cb != NULL) {
572 j = (alert_level << 8) | alert_descr;
573 cb(s, SSL_CB_READ_ALERT, j);
574 }
575
576 if (alert_level == SSL3_AL_WARNING) {
577 s->s3.warn_alert = alert_descr;
578 SSL3_RECORD_set_read(rr);
579
580 s->rlayer.alert_count++;
581 if (s->rlayer.alert_count == MAX_WARN_ALERT_COUNT) {
582 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_F_DTLS1_READ_BYTES,
583 SSL_R_TOO_MANY_WARN_ALERTS);
584 return -1;
585 }
586
587 if (alert_descr == SSL_AD_CLOSE_NOTIFY) {
588#ifndef OPENSSL_NO_SCTP
589 /*
590 * With SCTP and streams the socket may deliver app data
591 * after a close_notify alert. We have to check this first so
592 * that nothing gets discarded.
593 */
594 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
595 BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) {
596 s->d1->shutdown_received = 1;
597 s->rwstate = SSL_READING;
598 BIO_clear_retry_flags(SSL_get_rbio(s));
599 BIO_set_retry_read(SSL_get_rbio(s));
600 return -1;
601 }
602#endif
603 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
604 return 0;
605 }
606 } else if (alert_level == SSL3_AL_FATAL) {
607 char tmp[16];
608
609 s->rwstate = SSL_NOTHING;
610 s->s3.fatal_alert = alert_descr;
611 SSLfatal(s, SSL_AD_NO_ALERT, SSL_F_DTLS1_READ_BYTES,
612 SSL_AD_REASON_OFFSET + alert_descr);
613 BIO_snprintf(tmp, sizeof tmp, "%d", alert_descr);
614 ERR_add_error_data(2, "SSL alert number ", tmp);
615 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
616 SSL3_RECORD_set_read(rr);
617 SSL_CTX_remove_session(s->session_ctx, s->session);
618 return 0;
619 } else {
620 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_DTLS1_READ_BYTES,
621 SSL_R_UNKNOWN_ALERT_TYPE);
622 return -1;
623 }
624
625 goto start;
626 }
627
628 if (s->shutdown & SSL_SENT_SHUTDOWN) { /* but we have not received a
629 * shutdown */
630 s->rwstate = SSL_NOTHING;
631 SSL3_RECORD_set_length(rr, 0);
632 SSL3_RECORD_set_read(rr);
633 return 0;
634 }
635
636 if (SSL3_RECORD_get_type(rr) == SSL3_RT_CHANGE_CIPHER_SPEC) {
637 /*
638 * We can't process a CCS now, because previous handshake messages
639 * are still missing, so just drop it.
640 */
641 SSL3_RECORD_set_length(rr, 0);
642 SSL3_RECORD_set_read(rr);
643 goto start;
644 }
645
646 /*
647 * Unexpected handshake message (Client Hello, or protocol violation)
648 */
649 if ((SSL3_RECORD_get_type(rr) == SSL3_RT_HANDSHAKE) &&
650 !ossl_statem_get_in_handshake(s)) {
651 struct hm_header_st msg_hdr;
652
653 /*
654 * This may just be a stale retransmit. Also sanity check that we have
655 * at least enough record bytes for a message header
656 */
657 if (SSL3_RECORD_get_epoch(rr) != s->rlayer.d->r_epoch
658 || SSL3_RECORD_get_length(rr) < DTLS1_HM_HEADER_LENGTH) {
659 SSL3_RECORD_set_length(rr, 0);
660 SSL3_RECORD_set_read(rr);
661 goto start;
662 }
663
664 dtls1_get_message_header(rr->data, &msg_hdr);
665
666 /*
667 * If we are server, we may have a repeated FINISHED of the client
668 * here, then retransmit our CCS and FINISHED.
669 */
670 if (msg_hdr.type == SSL3_MT_FINISHED) {
671 if (dtls1_check_timeout_num(s) < 0) {
672 /* SSLfatal) already called */
673 return -1;
674 }
675
676 if (dtls1_retransmit_buffered_messages(s) <= 0) {
677 /* Fail if we encountered a fatal error */
678 if (ossl_statem_in_error(s))
679 return -1;
680 }
681 SSL3_RECORD_set_length(rr, 0);
682 SSL3_RECORD_set_read(rr);
683 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
684 if (SSL3_BUFFER_get_left(&s->rlayer.rbuf) == 0) {
685 /* no read-ahead left? */
686 BIO *bio;
687
688 s->rwstate = SSL_READING;
689 bio = SSL_get_rbio(s);
690 BIO_clear_retry_flags(bio);
691 BIO_set_retry_read(bio);
692 return -1;
693 }
694 }
695 goto start;
696 }
697
698 /*
699 * To get here we must be trying to read app data but found handshake
700 * data. But if we're trying to read app data, and we're not in init
701 * (which is tested for at the top of this function) then init must be
702 * finished
703 */
704 if (!ossl_assert(SSL_is_init_finished(s))) {
705 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DTLS1_READ_BYTES,
706 ERR_R_INTERNAL_ERROR);
707 return -1;
708 }
709
710 /* We found handshake data, so we're going back into init */
711 ossl_statem_set_in_init(s, 1);
712
713 i = s->handshake_func(s);
714 /* SSLfatal() called if appropriate */
715 if (i < 0)
716 return i;
717 if (i == 0)
718 return -1;
719
720 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
721 if (SSL3_BUFFER_get_left(&s->rlayer.rbuf) == 0) {
722 /* no read-ahead left? */
723 BIO *bio;
724 /*
725 * In the case where we try to read application data, but we
726 * trigger an SSL handshake, we return -1 with the retry
727 * option set. Otherwise renegotiation may cause nasty
728 * problems in the blocking world
729 */
730 s->rwstate = SSL_READING;
731 bio = SSL_get_rbio(s);
732 BIO_clear_retry_flags(bio);
733 BIO_set_retry_read(bio);
734 return -1;
735 }
736 }
737 goto start;
738 }
739
740 switch (SSL3_RECORD_get_type(rr)) {
741 default:
742 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_F_DTLS1_READ_BYTES,
743 SSL_R_UNEXPECTED_RECORD);
744 return -1;
745 case SSL3_RT_CHANGE_CIPHER_SPEC:
746 case SSL3_RT_ALERT:
747 case SSL3_RT_HANDSHAKE:
748 /*
749 * we already handled all of these, with the possible exception of
750 * SSL3_RT_HANDSHAKE when ossl_statem_get_in_handshake(s) is true, but
751 * that should not happen when type != rr->type
752 */
753 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_F_DTLS1_READ_BYTES,
754 ERR_R_INTERNAL_ERROR);
755 return -1;
756 case SSL3_RT_APPLICATION_DATA:
757 /*
758 * At this point, we were expecting handshake data, but have
759 * application data. If the library was running inside ssl3_read()
760 * (i.e. in_read_app_data is set) and it makes sense to read
761 * application data at this point (session renegotiation not yet
762 * started), we will indulge it.
763 */
764 if (s->s3.in_read_app_data &&
765 (s->s3.total_renegotiations != 0) &&
766 ossl_statem_app_data_allowed(s)) {
767 s->s3.in_read_app_data = 2;
768 return -1;
769 } else {
770 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_F_DTLS1_READ_BYTES,
771 SSL_R_UNEXPECTED_RECORD);
772 return -1;
773 }
774 }
775 /* not reached */
776}
777
778/*
779 * Call this to write data in records of type 'type' It will return <= 0 if
780 * not all data has been sent or non-blocking IO.
781 */
782int dtls1_write_bytes(SSL *s, int type, const void *buf, size_t len,
783 size_t *written)
784{
785 int i;
786
787 if (!ossl_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH)) {
788 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DTLS1_WRITE_BYTES,
789 ERR_R_INTERNAL_ERROR);
790 return -1;
791 }
792 s->rwstate = SSL_NOTHING;
793 i = do_dtls1_write(s, type, buf, len, 0, written);
794 return i;
795}
796
797int do_dtls1_write(SSL *s, int type, const unsigned char *buf,
798 size_t len, int create_empty_fragment, size_t *written)
799{
800 unsigned char *p, *pseq;
801 int i, mac_size, clear = 0;
802 size_t prefix_len = 0;
803 int eivlen;
804 SSL3_RECORD wr;
805 SSL3_BUFFER *wb;
806 SSL_SESSION *sess;
807
808 wb = &s->rlayer.wbuf[0];
809
810 /*
811 * first check if there is a SSL3_BUFFER still being written out. This
812 * will happen with non blocking IO
813 */
814 if (!ossl_assert(SSL3_BUFFER_get_left(wb) == 0)) {
815 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DO_DTLS1_WRITE,
816 ERR_R_INTERNAL_ERROR);
817 return 0;
818 }
819
820 /* If we have an alert to send, lets send it */
821 if (s->s3.alert_dispatch) {
822 i = s->method->ssl_dispatch_alert(s);
823 if (i <= 0)
824 return i;
825 /* if it went, fall through and send more stuff */
826 }
827
828 if (len == 0 && !create_empty_fragment)
829 return 0;
830
831 if (len > ssl_get_max_send_fragment(s)) {
832 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DO_DTLS1_WRITE,
833 SSL_R_EXCEEDS_MAX_FRAGMENT_SIZE);
834 return 0;
835 }
836
837 sess = s->session;
838
839 if ((sess == NULL) ||
840 (s->enc_write_ctx == NULL) || (EVP_MD_CTX_md(s->write_hash) == NULL))
841 clear = 1;
842
843 if (clear)
844 mac_size = 0;
845 else {
846 mac_size = EVP_MD_CTX_size(s->write_hash);
847 if (mac_size < 0) {
848 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DO_DTLS1_WRITE,
849 SSL_R_EXCEEDS_MAX_FRAGMENT_SIZE);
850 return -1;
851 }
852 }
853
854 p = SSL3_BUFFER_get_buf(wb) + prefix_len;
855
856 /* write the header */
857
858 *(p++) = type & 0xff;
859 SSL3_RECORD_set_type(&wr, type);
860 /*
861 * Special case: for hello verify request, client version 1.0 and we
862 * haven't decided which version to use yet send back using version 1.0
863 * header: otherwise some clients will ignore it.
864 */
865 if (s->method->version == DTLS_ANY_VERSION &&
866 s->max_proto_version != DTLS1_BAD_VER) {
867 *(p++) = DTLS1_VERSION >> 8;
868 *(p++) = DTLS1_VERSION & 0xff;
869 } else {
870 *(p++) = s->version >> 8;
871 *(p++) = s->version & 0xff;
872 }
873
874 /* field where we are to write out packet epoch, seq num and len */
875 pseq = p;
876 p += 10;
877
878 /* Explicit IV length, block ciphers appropriate version flag */
879 if (s->enc_write_ctx) {
880 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
881 if (mode == EVP_CIPH_CBC_MODE) {
882 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
883 if (eivlen <= 1)
884 eivlen = 0;
885 }
886 /* Need explicit part of IV for GCM mode */
887 else if (mode == EVP_CIPH_GCM_MODE)
888 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
889 else if (mode == EVP_CIPH_CCM_MODE)
890 eivlen = EVP_CCM_TLS_EXPLICIT_IV_LEN;
891 else
892 eivlen = 0;
893 } else
894 eivlen = 0;
895
896 /* lets setup the record stuff. */
897 SSL3_RECORD_set_data(&wr, p + eivlen); /* make room for IV in case of CBC */
898 SSL3_RECORD_set_length(&wr, len);
899 SSL3_RECORD_set_input(&wr, (unsigned char *)buf);
900
901 /*
902 * we now 'read' from wr.input, wr.length bytes into wr.data
903 */
904
905 /* first we compress */
906 if (s->compress != NULL) {
907 if (!ssl3_do_compress(s, &wr)) {
908 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DO_DTLS1_WRITE,
909 SSL_R_COMPRESSION_FAILURE);
910 return -1;
911 }
912 } else {
913 memcpy(SSL3_RECORD_get_data(&wr), SSL3_RECORD_get_input(&wr),
914 SSL3_RECORD_get_length(&wr));
915 SSL3_RECORD_reset_input(&wr);
916 }
917
918 /*
919 * we should still have the output to wr.data and the input from
920 * wr.input. Length should be wr.length. wr.data still points in the
921 * wb->buf
922 */
923
924 if (!SSL_WRITE_ETM(s) && mac_size != 0) {
925 if (!s->method->ssl3_enc->mac(s, &wr,
926 &(p[SSL3_RECORD_get_length(&wr) + eivlen]),
927 1)) {
928 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DO_DTLS1_WRITE,
929 ERR_R_INTERNAL_ERROR);
930 return -1;
931 }
932 SSL3_RECORD_add_length(&wr, mac_size);
933 }
934
935 /* this is true regardless of mac size */
936 SSL3_RECORD_set_data(&wr, p);
937 SSL3_RECORD_reset_input(&wr);
938
939 if (eivlen)
940 SSL3_RECORD_add_length(&wr, eivlen);
941
942 if (s->method->ssl3_enc->enc(s, &wr, 1, 1) < 1) {
943 if (!ossl_statem_in_error(s)) {
944 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DO_DTLS1_WRITE,
945 ERR_R_INTERNAL_ERROR);
946 }
947 return -1;
948 }
949
950 if (SSL_WRITE_ETM(s) && mac_size != 0) {
951 if (!s->method->ssl3_enc->mac(s, &wr,
952 &(p[SSL3_RECORD_get_length(&wr)]), 1)) {
953 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DO_DTLS1_WRITE,
954 ERR_R_INTERNAL_ERROR);
955 return -1;
956 }
957 SSL3_RECORD_add_length(&wr, mac_size);
958 }
959
960 /* record length after mac and block padding */
961
962 /* there's only one epoch between handshake and app data */
963
964 s2n(s->rlayer.d->w_epoch, pseq);
965
966 memcpy(pseq, &(s->rlayer.write_sequence[2]), 6);
967 pseq += 6;
968 s2n(SSL3_RECORD_get_length(&wr), pseq);
969
970 if (s->msg_callback)
971 s->msg_callback(1, 0, SSL3_RT_HEADER, pseq - DTLS1_RT_HEADER_LENGTH,
972 DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg);
973
974 /*
975 * we should now have wr.data pointing to the encrypted data, which is
976 * wr->length long
977 */
978 SSL3_RECORD_set_type(&wr, type); /* not needed but helps for debugging */
979 SSL3_RECORD_add_length(&wr, DTLS1_RT_HEADER_LENGTH);
980
981 ssl3_record_sequence_update(&(s->rlayer.write_sequence[0]));
982
983 if (create_empty_fragment) {
984 /*
985 * we are in a recursive call; just return the length, don't write
986 * out anything here
987 */
988 *written = wr.length;
989 return 1;
990 }
991
992 /* now let's set up wb */
993 SSL3_BUFFER_set_left(wb, prefix_len + SSL3_RECORD_get_length(&wr));
994 SSL3_BUFFER_set_offset(wb, 0);
995
996 /*
997 * memorize arguments so that ssl3_write_pending can detect bad write
998 * retries later
999 */
1000 s->rlayer.wpend_tot = len;
1001 s->rlayer.wpend_buf = buf;
1002 s->rlayer.wpend_type = type;
1003 s->rlayer.wpend_ret = len;
1004
1005 /* we now just need to write the buffer. Calls SSLfatal() as required. */
1006 return ssl3_write_pending(s, type, buf, len, written);
1007}
1008
1009DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr,
1010 unsigned int *is_next_epoch)
1011{
1012
1013 *is_next_epoch = 0;
1014
1015 /* In current epoch, accept HM, CCS, DATA, & ALERT */
1016 if (rr->epoch == s->rlayer.d->r_epoch)
1017 return &s->rlayer.d->bitmap;
1018
1019 /*
1020 * Only HM and ALERT messages can be from the next epoch and only if we
1021 * have already processed all of the unprocessed records from the last
1022 * epoch
1023 */
1024 else if (rr->epoch == (unsigned long)(s->rlayer.d->r_epoch + 1) &&
1025 s->rlayer.d->unprocessed_rcds.epoch != s->rlayer.d->r_epoch &&
1026 (rr->type == SSL3_RT_HANDSHAKE || rr->type == SSL3_RT_ALERT)) {
1027 *is_next_epoch = 1;
1028 return &s->rlayer.d->next_bitmap;
1029 }
1030
1031 return NULL;
1032}
1033
1034void dtls1_reset_seq_numbers(SSL *s, int rw)
1035{
1036 unsigned char *seq;
1037 unsigned int seq_bytes = sizeof(s->rlayer.read_sequence);
1038
1039 if (rw & SSL3_CC_READ) {
1040 seq = s->rlayer.read_sequence;
1041 s->rlayer.d->r_epoch++;
1042 memcpy(&s->rlayer.d->bitmap, &s->rlayer.d->next_bitmap,
1043 sizeof(s->rlayer.d->bitmap));
1044 memset(&s->rlayer.d->next_bitmap, 0, sizeof(s->rlayer.d->next_bitmap));
1045
1046 /*
1047 * We must not use any buffered messages received from the previous
1048 * epoch
1049 */
1050 dtls1_clear_received_buffer(s);
1051 } else {
1052 seq = s->rlayer.write_sequence;
1053 memcpy(s->rlayer.d->last_write_sequence, seq,
1054 sizeof(s->rlayer.write_sequence));
1055 s->rlayer.d->w_epoch++;
1056 }
1057
1058 memset(seq, 0, seq_bytes);
1059}
1060