1 /* ssl/record/rec_layer_d1.c */
3 * DTLS implementation written by Nagendra Modadugu
4 * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
6 /* ====================================================================
7 * Copyright (c) 1998-2005 The OpenSSL Project. All rights reserved.
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
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
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/)"
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.
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.
35 * 6. Redistributions of any form whatsoever must retain the following
37 * "This product includes software developed by the OpenSSL Project
38 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
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 * ====================================================================
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).
59 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
60 * All rights reserved.
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.
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).
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.
80 * Redistribution and use in source and binary forms, with or without
81 * modification, are permitted provided that the following conditions
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)"
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
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.]
119 #include "../ssl_locl.h"
120 #include <openssl/evp.h>
121 #include <openssl/buffer.h>
122 #include <openssl/pqueue.h>
123 #include <openssl/rand.h>
124 #include "record_locl.h"
126 int DTLS_RECORD_LAYER_new(RECORD_LAYER *rl)
128 DTLS_RECORD_LAYER *d;
130 if ((d = OPENSSL_malloc(sizeof *d)) == NULL) {
137 d->unprocessed_rcds.q = pqueue_new();
138 d->processed_rcds.q = pqueue_new();
139 d->buffered_app_data.q = pqueue_new();
141 if (!d->unprocessed_rcds.q || !d->processed_rcds.q
142 || !d->buffered_app_data.q) {
143 if (d->unprocessed_rcds.q)
144 pqueue_free(d->unprocessed_rcds.q);
145 if (d->processed_rcds.q)
146 pqueue_free(d->processed_rcds.q);
147 if (d->buffered_app_data.q)
148 pqueue_free(d->buffered_app_data.q);
157 void DTLS_RECORD_LAYER_free(RECORD_LAYER *rl)
159 DTLS_RECORD_LAYER_clear(rl);
160 pqueue_free(rl->d->unprocessed_rcds.q);
161 pqueue_free(rl->d->processed_rcds.q);
162 pqueue_free(rl->d->buffered_app_data.q);
167 void DTLS_RECORD_LAYER_clear(RECORD_LAYER *rl)
169 DTLS_RECORD_LAYER *d;
171 DTLS1_RECORD_DATA *rdata;
172 pqueue unprocessed_rcds;
173 pqueue processed_rcds;
174 pqueue buffered_app_data;
178 while ((item = pqueue_pop(d->unprocessed_rcds.q)) != NULL) {
179 rdata = (DTLS1_RECORD_DATA *)item->data;
180 if (rdata->rbuf.buf) {
181 OPENSSL_free(rdata->rbuf.buf);
183 OPENSSL_free(item->data);
187 while ((item = pqueue_pop(d->processed_rcds.q)) != NULL) {
188 rdata = (DTLS1_RECORD_DATA *)item->data;
189 if (rdata->rbuf.buf) {
190 OPENSSL_free(rdata->rbuf.buf);
192 OPENSSL_free(item->data);
196 while ((item = pqueue_pop(d->buffered_app_data.q)) != NULL) {
197 rdata = (DTLS1_RECORD_DATA *)item->data;
198 if (rdata->rbuf.buf) {
199 OPENSSL_free(rdata->rbuf.buf);
201 OPENSSL_free(item->data);
205 unprocessed_rcds = d->unprocessed_rcds.q;
206 processed_rcds = d->processed_rcds.q;
207 buffered_app_data = d->buffered_app_data.q;
208 memset(d, 0, sizeof *d);
209 d->unprocessed_rcds.q = unprocessed_rcds;
210 d->processed_rcds.q = processed_rcds;
211 d->buffered_app_data.q = buffered_app_data;
214 void DTLS_RECORD_LAYER_set_saved_w_epoch(RECORD_LAYER *rl, unsigned short e)
216 if (e == rl->d->w_epoch - 1) {
217 memcpy(rl->d->curr_write_sequence,
219 sizeof(rl->write_sequence));
220 memcpy(rl->write_sequence,
221 rl->d->last_write_sequence,
222 sizeof(rl->write_sequence));
223 } else if (e == rl->d->w_epoch + 1) {
224 memcpy(rl->d->last_write_sequence,
226 sizeof(unsigned char[8]));
227 memcpy(rl->write_sequence,
228 rl->d->curr_write_sequence,
229 sizeof(rl->write_sequence));
234 void DTLS_RECORD_LAYER_resync_write(RECORD_LAYER *rl)
236 memcpy(rl->write_sequence, rl->read_sequence, sizeof(rl->write_sequence));
239 static int have_handshake_fragment(SSL *s, int type, unsigned char *buf,
242 /* copy buffered record into SSL structure */
243 static int dtls1_copy_record(SSL *s, pitem *item)
245 DTLS1_RECORD_DATA *rdata;
247 rdata = (DTLS1_RECORD_DATA *)item->data;
249 SSL3_BUFFER_release(&s->rlayer.rbuf);
251 s->rlayer.packet = rdata->packet;
252 s->rlayer.packet_length = rdata->packet_length;
253 memcpy(&s->rlayer.rbuf, &(rdata->rbuf), sizeof(SSL3_BUFFER));
254 memcpy(&s->rlayer.rrec, &(rdata->rrec), sizeof(SSL3_RECORD));
256 /* Set proper sequence number for mac calculation */
257 memcpy(&(s->rlayer.read_sequence[2]), &(rdata->packet[5]), 6);
263 dtls1_buffer_record(SSL *s, record_pqueue *queue, unsigned char *priority)
265 DTLS1_RECORD_DATA *rdata;
268 /* Limit the size of the queue to prevent DOS attacks */
269 if (pqueue_size(queue->q) >= 100)
272 rdata = OPENSSL_malloc(sizeof(DTLS1_RECORD_DATA));
273 item = pitem_new(priority, rdata);
274 if (rdata == NULL || item == NULL) {
280 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
284 rdata->packet = s->rlayer.packet;
285 rdata->packet_length = s->rlayer.packet_length;
286 memcpy(&(rdata->rbuf), &s->rlayer.rbuf, sizeof(SSL3_BUFFER));
287 memcpy(&(rdata->rrec), &s->rlayer.rrec, sizeof(SSL3_RECORD));
291 #ifndef OPENSSL_NO_SCTP
292 /* Store bio_dgram_sctp_rcvinfo struct */
293 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
294 (s->state == SSL3_ST_SR_FINISHED_A
295 || s->state == SSL3_ST_CR_FINISHED_A)) {
296 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_GET_RCVINFO,
297 sizeof(rdata->recordinfo), &rdata->recordinfo);
301 s->rlayer.packet = NULL;
302 s->rlayer.packet_length = 0;
303 memset(&s->rlayer.rbuf, 0, sizeof(SSL3_BUFFER));
304 memset(&s->rlayer.rrec, 0, sizeof(SSL3_RECORD));
306 if (!ssl3_setup_buffers(s)) {
307 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
308 if (rdata->rbuf.buf != NULL)
309 OPENSSL_free(rdata->rbuf.buf);
315 /* insert should not fail, since duplicates are dropped */
316 if (pqueue_insert(queue->q, item) == NULL) {
317 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
318 if (rdata->rbuf.buf != NULL)
319 OPENSSL_free(rdata->rbuf.buf);
328 int dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue)
332 item = pqueue_pop(queue->q);
334 dtls1_copy_record(s, item);
336 OPENSSL_free(item->data);
346 * retrieve a buffered record that belongs to the new epoch, i.e., not
349 #define dtls1_get_unprocessed_record(s) \
350 dtls1_retrieve_buffered_record((s), \
351 &((s)->rlayer.d->unprocessed_rcds))
354 int dtls1_process_buffered_records(SSL *s)
358 item = pqueue_peek(s->rlayer.d->unprocessed_rcds.q);
360 /* Check if epoch is current. */
361 if (s->rlayer.d->unprocessed_rcds.epoch != s->rlayer.d->r_epoch)
362 return (1); /* Nothing to do. */
364 /* Process all the records. */
365 while (pqueue_peek(s->rlayer.d->unprocessed_rcds.q)) {
366 dtls1_get_unprocessed_record(s);
367 if (!dtls1_process_record(s))
369 if (dtls1_buffer_record(s, &(s->rlayer.d->processed_rcds),
370 SSL3_RECORD_get_seq_num(&s->rlayer.rrec)) < 0)
376 * sync epoch numbers once all the unprocessed records have been
379 s->rlayer.d->processed_rcds.epoch = s->rlayer.d->r_epoch;
380 s->rlayer.d->unprocessed_rcds.epoch = s->rlayer.d->r_epoch + 1;
387 * Return up to 'len' payload bytes received in 'type' records.
388 * 'type' is one of the following:
390 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
391 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
392 * - 0 (during a shutdown, no data has to be returned)
394 * If we don't have stored data to work from, read a SSL/TLS record first
395 * (possibly multiple records if we still don't have anything to return).
397 * This function must handle any surprises the peer may have for us, such as
398 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
399 * a surprise, but handled as if it were), or renegotiation requests.
400 * Also if record payloads contain fragments too small to process, we store
401 * them until there is enough for the respective protocol (the record protocol
402 * may use arbitrary fragmentation and even interleaving):
403 * Change cipher spec protocol
404 * just 1 byte needed, no need for keeping anything stored
406 * 2 bytes needed (AlertLevel, AlertDescription)
408 * 4 bytes needed (HandshakeType, uint24 length) -- we just have
409 * to detect unexpected Client Hello and Hello Request messages
410 * here, anything else is handled by higher layers
411 * Application data protocol
412 * none of our business
414 int dtls1_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
419 void (*cb) (const SSL *ssl, int type2, int val) = NULL;
421 if (!SSL3_BUFFER_is_initialised(&s->rlayer.rbuf)) {
422 /* Not initialized yet */
423 if (!ssl3_setup_buffers(s))
427 if ((type && (type != SSL3_RT_APPLICATION_DATA) &&
428 (type != SSL3_RT_HANDSHAKE)) ||
429 (peek && (type != SSL3_RT_APPLICATION_DATA))) {
430 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
435 * check whether there's a handshake message (client hello?) waiting
437 if ((ret = have_handshake_fragment(s, type, buf, len, peek)))
441 * Now s->rlayer.d->handshake_fragment_len == 0 if
442 * type == SSL3_RT_HANDSHAKE.
445 #ifndef OPENSSL_NO_SCTP
447 * Continue handshake if it had to be interrupted to read app data with
450 if ((!s->in_handshake && SSL_in_init(s)) ||
451 (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
452 (s->state == DTLS1_SCTP_ST_SR_READ_SOCK
453 || s->state == DTLS1_SCTP_ST_CR_READ_SOCK)
454 && s->s3->in_read_app_data != 2))
456 if (!s->in_handshake && SSL_in_init(s))
459 /* type == SSL3_RT_APPLICATION_DATA */
460 i = s->handshake_func(s);
464 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
470 s->rwstate = SSL_NOTHING;
473 * s->s3->rrec.type - is the type of record
474 * s->s3->rrec.data, - data
475 * s->s3->rrec.off, - offset into 'data' for next read
476 * s->s3->rrec.length, - number of bytes.
478 rr = &s->rlayer.rrec;
481 * We are not handshaking and have no data yet, so process data buffered
482 * during the last handshake in advance, if any.
484 if (s->state == SSL_ST_OK && rr->length == 0) {
486 item = pqueue_pop(s->rlayer.d->buffered_app_data.q);
488 #ifndef OPENSSL_NO_SCTP
489 /* Restore bio_dgram_sctp_rcvinfo struct */
490 if (BIO_dgram_is_sctp(SSL_get_rbio(s))) {
491 DTLS1_RECORD_DATA *rdata = (DTLS1_RECORD_DATA *)item->data;
492 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_SET_RCVINFO,
493 sizeof(rdata->recordinfo), &rdata->recordinfo);
497 dtls1_copy_record(s, item);
499 OPENSSL_free(item->data);
504 /* Check for timeout */
505 if (dtls1_handle_timeout(s) > 0)
508 /* get new packet if necessary */
509 if ((rr->length == 0) || (s->rlayer.rstate == SSL_ST_READ_BODY)) {
510 ret = dtls1_get_record(s);
512 ret = dtls1_read_failed(s, ret);
513 /* anything other than a timeout is an error */
521 if (s->d1->listen && rr->type != SSL3_RT_HANDSHAKE) {
526 /* we now have a packet which can be read and processed */
528 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
529 * reset by ssl3_get_finished */
530 && (rr->type != SSL3_RT_HANDSHAKE)) {
532 * We now have application data between CCS and Finished. Most likely
533 * the packets were reordered on their way, so buffer the application
534 * data for later processing rather than dropping the connection.
536 if (dtls1_buffer_record(s, &(s->rlayer.d->buffered_app_data),
538 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
546 * If the other end has shut down, throw anything we read away (even in
549 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) {
551 s->rwstate = SSL_NOTHING;
555 if (type == rr->type) { /* SSL3_RT_APPLICATION_DATA or
556 * SSL3_RT_HANDSHAKE */
558 * make sure that we are not getting application data when we are
559 * doing a handshake for the first time
561 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
562 (s->enc_read_ctx == NULL)) {
563 al = SSL_AD_UNEXPECTED_MESSAGE;
564 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_APP_DATA_IN_HANDSHAKE);
571 if ((unsigned int)len > rr->length)
574 n = (unsigned int)len;
576 memcpy(buf, &(rr->data[rr->off]), n);
580 if (rr->length == 0) {
581 s->rlayer.rstate = SSL_ST_READ_HEADER;
585 #ifndef OPENSSL_NO_SCTP
587 * We were about to renegotiate but had to read belated application
588 * data first, so retry.
590 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
591 rr->type == SSL3_RT_APPLICATION_DATA &&
592 (s->state == DTLS1_SCTP_ST_SR_READ_SOCK
593 || s->state == DTLS1_SCTP_ST_CR_READ_SOCK)) {
594 s->rwstate = SSL_READING;
595 BIO_clear_retry_flags(SSL_get_rbio(s));
596 BIO_set_retry_read(SSL_get_rbio(s));
600 * We might had to delay a close_notify alert because of reordered
601 * app data. If there was an alert and there is no message to read
602 * anymore, finally set shutdown.
604 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
605 s->d1->shutdown_received
606 && !BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) {
607 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
615 * If we get here, then type != rr->type; if we have a handshake message,
616 * then it was unexpected (Hello Request or Client Hello).
620 * In case of record types for which we have 'fragment' storage, fill
621 * that so that we can process the data at a fixed place.
624 unsigned int k, dest_maxlen = 0;
625 unsigned char *dest = NULL;
626 unsigned int *dest_len = NULL;
628 if (rr->type == SSL3_RT_HANDSHAKE) {
629 dest_maxlen = sizeof s->rlayer.d->handshake_fragment;
630 dest = s->rlayer.d->handshake_fragment;
631 dest_len = &s->rlayer.d->handshake_fragment_len;
632 } else if (rr->type == SSL3_RT_ALERT) {
633 dest_maxlen = sizeof(s->rlayer.d->alert_fragment);
634 dest = s->rlayer.d->alert_fragment;
635 dest_len = &s->rlayer.d->alert_fragment_len;
637 #ifndef OPENSSL_NO_HEARTBEATS
638 else if (rr->type == TLS1_RT_HEARTBEAT) {
639 /* We allow a 0 return */
640 if(dtls1_process_heartbeat(s, SSL3_RECORD_get_data(&s->rlayer.rrec),
641 SSL3_RECORD_get_length(&s->rlayer.rrec)) < 0) {
644 /* Exit and notify application to read again */
646 s->rwstate = SSL_READING;
647 BIO_clear_retry_flags(SSL_get_rbio(s));
648 BIO_set_retry_read(SSL_get_rbio(s));
652 /* else it's a CCS message, or application data or wrong */
653 else if (rr->type != SSL3_RT_CHANGE_CIPHER_SPEC) {
655 * Application data while renegotiating is allowed. Try again
658 if (rr->type == SSL3_RT_APPLICATION_DATA) {
660 s->s3->in_read_app_data = 2;
661 bio = SSL_get_rbio(s);
662 s->rwstate = SSL_READING;
663 BIO_clear_retry_flags(bio);
664 BIO_set_retry_read(bio);
668 /* Not certain if this is the right error handling */
669 al = SSL_AD_UNEXPECTED_MESSAGE;
670 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
674 if (dest_maxlen > 0) {
676 * XDTLS: In a pathalogical case, the Client Hello may be
677 * fragmented--don't always expect dest_maxlen bytes
679 if (rr->length < dest_maxlen) {
680 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
682 * for normal alerts rr->length is 2, while
683 * dest_maxlen is 7 if we were to handle this
684 * non-existing alert...
688 s->rlayer.rstate = SSL_ST_READ_HEADER;
693 /* now move 'n' bytes: */
694 for (k = 0; k < dest_maxlen; k++) {
695 dest[k] = rr->data[rr->off++];
698 *dest_len = dest_maxlen;
703 * s->rlayer.d->handshake_fragment_len == 12 iff rr->type == SSL3_RT_HANDSHAKE;
704 * s->rlayer.d->alert_fragment_len == 7 iff rr->type == SSL3_RT_ALERT.
705 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.)
708 /* If we are a client, check for an incoming 'Hello Request': */
710 (s->rlayer.d->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
711 (s->rlayer.d->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
712 (s->session != NULL) && (s->session->cipher != NULL)) {
713 s->rlayer.d->handshake_fragment_len = 0;
715 if ((s->rlayer.d->handshake_fragment[1] != 0) ||
716 (s->rlayer.d->handshake_fragment[2] != 0) ||
717 (s->rlayer.d->handshake_fragment[3] != 0)) {
718 al = SSL_AD_DECODE_ERROR;
719 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_BAD_HELLO_REQUEST);
724 * no need to check sequence number on HELLO REQUEST messages
728 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
729 s->rlayer.d->handshake_fragment, 4, s,
730 s->msg_callback_arg);
732 if (SSL_is_init_finished(s) &&
733 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
734 !s->s3->renegotiate) {
735 s->d1->handshake_read_seq++;
738 if (ssl3_renegotiate_check(s)) {
739 i = s->handshake_func(s);
743 SSLerr(SSL_F_DTLS1_READ_BYTES,
744 SSL_R_SSL_HANDSHAKE_FAILURE);
748 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
749 if (SSL3_BUFFER_get_left(&s->rlayer.rbuf) == 0) {
750 /* no read-ahead left? */
753 * In the case where we try to read application data,
754 * but we trigger an SSL handshake, we return -1 with
755 * the retry option set. Otherwise renegotiation may
756 * cause nasty problems in the blocking world
758 s->rwstate = SSL_READING;
759 bio = SSL_get_rbio(s);
760 BIO_clear_retry_flags(bio);
761 BIO_set_retry_read(bio);
768 * we either finished a handshake or ignored the request, now try
769 * again to obtain the (application) data we were asked for
774 if (s->rlayer.d->alert_fragment_len >= DTLS1_AL_HEADER_LENGTH) {
775 int alert_level = s->rlayer.d->alert_fragment[0];
776 int alert_descr = s->rlayer.d->alert_fragment[1];
778 s->rlayer.d->alert_fragment_len = 0;
781 s->msg_callback(0, s->version, SSL3_RT_ALERT,
782 s->rlayer.d->alert_fragment, 2, s,
783 s->msg_callback_arg);
785 if (s->info_callback != NULL)
786 cb = s->info_callback;
787 else if (s->ctx->info_callback != NULL)
788 cb = s->ctx->info_callback;
791 j = (alert_level << 8) | alert_descr;
792 cb(s, SSL_CB_READ_ALERT, j);
795 if (alert_level == SSL3_AL_WARNING) {
796 s->s3->warn_alert = alert_descr;
797 if (alert_descr == SSL_AD_CLOSE_NOTIFY) {
798 #ifndef OPENSSL_NO_SCTP
800 * With SCTP and streams the socket may deliver app data
801 * after a close_notify alert. We have to check this first so
802 * that nothing gets discarded.
804 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
805 BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) {
806 s->d1->shutdown_received = 1;
807 s->rwstate = SSL_READING;
808 BIO_clear_retry_flags(SSL_get_rbio(s));
809 BIO_set_retry_read(SSL_get_rbio(s));
813 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
817 /* XXX: this is a possible improvement in the future */
818 /* now check if it's a missing record */
819 if (alert_descr == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE) {
821 unsigned int frag_off;
822 unsigned char *p = &(s->rlayer.d->alert_fragment[2]);
827 dtls1_retransmit_message(s,
828 dtls1_get_queue_priority
829 (frag->msg_header.seq, 0), frag_off,
831 if (!found && SSL_in_init(s)) {
833 * fprintf( stderr,"in init = %d\n", SSL_in_init(s));
836 * requested a message not yet sent, send an alert
839 ssl3_send_alert(s, SSL3_AL_WARNING,
840 DTLS1_AD_MISSING_HANDSHAKE_MESSAGE);
844 } else if (alert_level == SSL3_AL_FATAL) {
847 s->rwstate = SSL_NOTHING;
848 s->s3->fatal_alert = alert_descr;
849 SSLerr(SSL_F_DTLS1_READ_BYTES,
850 SSL_AD_REASON_OFFSET + alert_descr);
851 BIO_snprintf(tmp, sizeof tmp, "%d", alert_descr);
852 ERR_add_error_data(2, "SSL alert number ", tmp);
853 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
854 SSL_CTX_remove_session(s->ctx, s->session);
857 al = SSL_AD_ILLEGAL_PARAMETER;
858 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNKNOWN_ALERT_TYPE);
865 if (s->shutdown & SSL_SENT_SHUTDOWN) { /* but we have not received a
867 s->rwstate = SSL_NOTHING;
872 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) {
873 struct ccs_header_st ccs_hdr;
874 unsigned int ccs_hdr_len = DTLS1_CCS_HEADER_LENGTH;
876 dtls1_get_ccs_header(rr->data, &ccs_hdr);
878 if (s->version == DTLS1_BAD_VER)
882 * 'Change Cipher Spec' is just a single byte, so we know exactly
883 * what the record payload has to look like
885 /* XDTLS: check that epoch is consistent */
886 if ((rr->length != ccs_hdr_len) ||
887 (rr->off != 0) || (rr->data[0] != SSL3_MT_CCS)) {
888 i = SSL_AD_ILLEGAL_PARAMETER;
889 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_BAD_CHANGE_CIPHER_SPEC);
896 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC,
897 rr->data, 1, s, s->msg_callback_arg);
900 * We can't process a CCS now, because previous handshake messages
901 * are still missing, so just drop it.
903 if (!s->d1->change_cipher_spec_ok) {
907 s->d1->change_cipher_spec_ok = 0;
909 s->s3->change_cipher_spec = 1;
910 if (!ssl3_do_change_cipher_spec(s))
913 /* do this whenever CCS is processed */
914 dtls1_reset_seq_numbers(s, SSL3_CC_READ);
916 if (s->version == DTLS1_BAD_VER)
917 s->d1->handshake_read_seq++;
919 #ifndef OPENSSL_NO_SCTP
921 * Remember that a CCS has been received, so that an old key of
922 * SCTP-Auth can be deleted when a CCS is sent. Will be ignored if no
925 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD, 1, NULL);
932 * Unexpected handshake message (Client Hello, or protocol violation)
934 if ((s->rlayer.d->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
936 struct hm_header_st msg_hdr;
938 /* this may just be a stale retransmit */
939 dtls1_get_message_header(rr->data, &msg_hdr);
940 if (rr->epoch != s->rlayer.d->r_epoch) {
946 * If we are server, we may have a repeated FINISHED of the client
947 * here, then retransmit our CCS and FINISHED.
949 if (msg_hdr.type == SSL3_MT_FINISHED) {
950 if (dtls1_check_timeout_num(s) < 0)
953 dtls1_retransmit_buffered_messages(s);
958 if (((s->state & SSL_ST_MASK) == SSL_ST_OK) &&
959 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) {
960 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
964 i = s->handshake_func(s);
968 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
972 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
973 if (SSL3_BUFFER_get_left(&s->rlayer.rbuf) == 0) {
974 /* no read-ahead left? */
977 * In the case where we try to read application data, but we
978 * trigger an SSL handshake, we return -1 with the retry
979 * option set. Otherwise renegotiation may cause nasty
980 * problems in the blocking world
982 s->rwstate = SSL_READING;
983 bio = SSL_get_rbio(s);
984 BIO_clear_retry_flags(bio);
985 BIO_set_retry_read(bio);
994 /* TLS just ignores unknown message types */
995 if (s->version == TLS1_VERSION) {
999 al = SSL_AD_UNEXPECTED_MESSAGE;
1000 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
1002 case SSL3_RT_CHANGE_CIPHER_SPEC:
1004 case SSL3_RT_HANDSHAKE:
1006 * we already handled all of these, with the possible exception of
1007 * SSL3_RT_HANDSHAKE when s->in_handshake is set, but that should not
1008 * happen when type != rr->type
1010 al = SSL_AD_UNEXPECTED_MESSAGE;
1011 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
1013 case SSL3_RT_APPLICATION_DATA:
1015 * At this point, we were expecting handshake data, but have
1016 * application data. If the library was running inside ssl3_read()
1017 * (i.e. in_read_app_data is set) and it makes sense to read
1018 * application data at this point (session renegotiation not yet
1019 * started), we will indulge it.
1021 if (s->s3->in_read_app_data &&
1022 (s->s3->total_renegotiations != 0) &&
1023 (((s->state & SSL_ST_CONNECT) &&
1024 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1025 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1026 ) || ((s->state & SSL_ST_ACCEPT) &&
1027 (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1028 (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1031 s->s3->in_read_app_data = 2;
1034 al = SSL_AD_UNEXPECTED_MESSAGE;
1035 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
1042 ssl3_send_alert(s, SSL3_AL_FATAL, al);
1049 * this only happens when a client hello is received and a handshake
1053 have_handshake_fragment(SSL *s, int type, unsigned char *buf,
1057 if ((type == SSL3_RT_HANDSHAKE)
1058 && (s->rlayer.d->handshake_fragment_len > 0))
1059 /* (partially) satisfy request from storage */
1061 unsigned char *src = s->rlayer.d->handshake_fragment;
1062 unsigned char *dst = buf;
1067 while ((len > 0) && (s->rlayer.d->handshake_fragment_len > 0)) {
1070 s->rlayer.d->handshake_fragment_len--;
1073 /* move any remaining fragment bytes: */
1074 for (k = 0; k < s->rlayer.d->handshake_fragment_len; k++)
1075 s->rlayer.d->handshake_fragment[k] = *src++;
1083 * Call this to write data in records of type 'type' It will return <= 0 if
1084 * not all data has been sent or non-blocking IO.
1086 int dtls1_write_bytes(SSL *s, int type, const void *buf, int len)
1090 OPENSSL_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH);
1091 s->rwstate = SSL_NOTHING;
1092 i = do_dtls1_write(s, type, buf, len, 0);
1096 int do_dtls1_write(SSL *s, int type, const unsigned char *buf,
1097 unsigned int len, int create_empty_fragment)
1099 unsigned char *p, *pseq;
1100 int i, mac_size, clear = 0;
1107 wb = &s->rlayer.wbuf;
1110 * first check if there is a SSL3_BUFFER still being written out. This
1111 * will happen with non blocking IO
1113 if (SSL3_BUFFER_get_left(wb) != 0) {
1114 OPENSSL_assert(0); /* XDTLS: want to see if we ever get here */
1115 return (ssl3_write_pending(s, type, buf, len));
1118 /* If we have an alert to send, lets send it */
1119 if (s->s3->alert_dispatch) {
1120 i = s->method->ssl_dispatch_alert(s);
1123 /* if it went, fall through and send more stuff */
1126 if (len == 0 && !create_empty_fragment)
1129 wr = &s->rlayer.wrec;
1132 if ((sess == NULL) ||
1133 (s->enc_write_ctx == NULL) || (EVP_MD_CTX_md(s->write_hash) == NULL))
1139 mac_size = EVP_MD_CTX_size(s->write_hash);
1144 p = wb->buf + prefix_len;
1146 /* write the header */
1148 *(p++) = type & 0xff;
1151 * Special case: for hello verify request, client version 1.0 and we
1152 * haven't decided which version to use yet send back using version 1.0
1153 * header: otherwise some clients will ignore it.
1155 if (s->method->version == DTLS_ANY_VERSION) {
1156 *(p++) = DTLS1_VERSION >> 8;
1157 *(p++) = DTLS1_VERSION & 0xff;
1159 *(p++) = s->version >> 8;
1160 *(p++) = s->version & 0xff;
1163 /* field where we are to write out packet epoch, seq num and len */
1167 /* Explicit IV length, block ciphers appropriate version flag */
1168 if (s->enc_write_ctx) {
1169 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
1170 if (mode == EVP_CIPH_CBC_MODE) {
1171 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
1175 /* Need explicit part of IV for GCM mode */
1176 else if (mode == EVP_CIPH_GCM_MODE)
1177 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
1183 /* lets setup the record stuff. */
1184 wr->data = p + eivlen; /* make room for IV in case of CBC */
1185 wr->length = (int)len;
1186 wr->input = (unsigned char *)buf;
1189 * we now 'read' from wr->input, wr->length bytes into wr->data
1192 /* first we compress */
1193 if (s->compress != NULL) {
1194 if (!ssl3_do_compress(s)) {
1195 SSLerr(SSL_F_DO_DTLS1_WRITE, SSL_R_COMPRESSION_FAILURE);
1199 memcpy(wr->data, wr->input, wr->length);
1200 wr->input = wr->data;
1204 * we should still have the output to wr->data and the input from
1205 * wr->input. Length should be wr->length. wr->data still points in the
1209 if (mac_size != 0) {
1210 if (s->method->ssl3_enc->mac(s, &(p[wr->length + eivlen]), 1) < 0)
1212 wr->length += mac_size;
1215 /* this is true regardless of mac size */
1220 wr->length += eivlen;
1222 if (s->method->ssl3_enc->enc(s, 1) < 1)
1225 /* record length after mac and block padding */
1227 * if (type == SSL3_RT_APPLICATION_DATA || (type == SSL3_RT_ALERT && !
1231 /* there's only one epoch between handshake and app data */
1233 s2n(s->rlayer.d->w_epoch, pseq);
1237 * else s2n(s->d1->handshake_epoch, pseq);
1240 memcpy(pseq, &(s->rlayer.write_sequence[2]), 6);
1242 s2n(wr->length, pseq);
1244 if (s->msg_callback)
1245 s->msg_callback(1, 0, SSL3_RT_HEADER, pseq - DTLS1_RT_HEADER_LENGTH,
1246 DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg);
1249 * we should now have wr->data pointing to the encrypted data, which is
1252 wr->type = type; /* not needed but helps for debugging */
1253 wr->length += DTLS1_RT_HEADER_LENGTH;
1255 ssl3_record_sequence_update(&(s->rlayer.write_sequence[0]));
1257 if (create_empty_fragment) {
1259 * we are in a recursive call; just return the length, don't write
1265 /* now let's set up wb */
1266 wb->left = prefix_len + wr->length;
1270 * memorize arguments so that ssl3_write_pending can detect bad write
1273 s->rlayer.wpend_tot = len;
1274 s->rlayer.wpend_buf = buf;
1275 s->rlayer.wpend_type = type;
1276 s->rlayer.wpend_ret = len;
1278 /* we now just need to write the buffer */
1279 return ssl3_write_pending(s, type, buf, len);
1284 DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr,
1285 unsigned int *is_next_epoch)
1290 /* In current epoch, accept HM, CCS, DATA, & ALERT */
1291 if (rr->epoch == s->rlayer.d->r_epoch)
1292 return &s->rlayer.d->bitmap;
1294 /* Only HM and ALERT messages can be from the next epoch */
1295 else if (rr->epoch == (unsigned long)(s->rlayer.d->r_epoch + 1) &&
1296 (rr->type == SSL3_RT_HANDSHAKE || rr->type == SSL3_RT_ALERT)) {
1298 return &s->rlayer.d->next_bitmap;
1304 void dtls1_reset_seq_numbers(SSL *s, int rw)
1307 unsigned int seq_bytes = sizeof(s->rlayer.read_sequence);
1309 if (rw & SSL3_CC_READ) {
1310 seq = s->rlayer.read_sequence;
1311 s->rlayer.d->r_epoch++;
1312 memcpy(&(s->rlayer.d->bitmap), &(s->rlayer.d->next_bitmap),
1313 sizeof(DTLS1_BITMAP));
1314 memset(&(s->rlayer.d->next_bitmap), 0x00, sizeof(DTLS1_BITMAP));
1316 seq = s->rlayer.write_sequence;
1317 memcpy(s->rlayer.d->last_write_sequence, seq,
1318 sizeof(s->rlayer.write_sequence));
1319 s->rlayer.d->w_epoch++;
1322 memset(seq, 0x00, seq_bytes);