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);
262 int dtls1_buffer_record(SSL *s, record_pqueue *queue, unsigned char *priority)
264 DTLS1_RECORD_DATA *rdata;
267 /* Limit the size of the queue to prevent DOS attacks */
268 if (pqueue_size(queue->q) >= 100)
271 rdata = OPENSSL_malloc(sizeof(DTLS1_RECORD_DATA));
272 item = pitem_new(priority, rdata);
273 if (rdata == NULL || item == NULL) {
279 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
283 rdata->packet = s->rlayer.packet;
284 rdata->packet_length = s->rlayer.packet_length;
285 memcpy(&(rdata->rbuf), &s->rlayer.rbuf, sizeof(SSL3_BUFFER));
286 memcpy(&(rdata->rrec), &s->rlayer.rrec, sizeof(SSL3_RECORD));
290 #ifndef OPENSSL_NO_SCTP
291 /* Store bio_dgram_sctp_rcvinfo struct */
292 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
293 (s->state == SSL3_ST_SR_FINISHED_A
294 || s->state == SSL3_ST_CR_FINISHED_A)) {
295 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_GET_RCVINFO,
296 sizeof(rdata->recordinfo), &rdata->recordinfo);
300 s->rlayer.packet = NULL;
301 s->rlayer.packet_length = 0;
302 memset(&s->rlayer.rbuf, 0, sizeof(SSL3_BUFFER));
303 memset(&s->rlayer.rrec, 0, sizeof(SSL3_RECORD));
305 if (!ssl3_setup_buffers(s)) {
306 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
307 if (rdata->rbuf.buf != NULL)
308 OPENSSL_free(rdata->rbuf.buf);
314 /* insert should not fail, since duplicates are dropped */
315 if (pqueue_insert(queue->q, item) == NULL) {
316 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
317 if (rdata->rbuf.buf != NULL)
318 OPENSSL_free(rdata->rbuf.buf);
327 int dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue)
331 item = pqueue_pop(queue->q);
333 dtls1_copy_record(s, item);
335 OPENSSL_free(item->data);
345 * retrieve a buffered record that belongs to the new epoch, i.e., not
348 #define dtls1_get_unprocessed_record(s) \
349 dtls1_retrieve_buffered_record((s), \
350 &((s)->rlayer.d->unprocessed_rcds))
353 int dtls1_process_buffered_records(SSL *s)
357 item = pqueue_peek(s->rlayer.d->unprocessed_rcds.q);
359 /* Check if epoch is current. */
360 if (s->rlayer.d->unprocessed_rcds.epoch != s->rlayer.d->r_epoch)
361 return (1); /* Nothing to do. */
363 /* Process all the records. */
364 while (pqueue_peek(s->rlayer.d->unprocessed_rcds.q)) {
365 dtls1_get_unprocessed_record(s);
366 if (!dtls1_process_record(s))
368 if (dtls1_buffer_record(s, &(s->rlayer.d->processed_rcds),
369 SSL3_RECORD_get_seq_num(&s->rlayer.rrec)) < 0)
375 * sync epoch numbers once all the unprocessed records have been
378 s->rlayer.d->processed_rcds.epoch = s->rlayer.d->r_epoch;
379 s->rlayer.d->unprocessed_rcds.epoch = s->rlayer.d->r_epoch + 1;
386 * Return up to 'len' payload bytes received in 'type' records.
387 * 'type' is one of the following:
389 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
390 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
391 * - 0 (during a shutdown, no data has to be returned)
393 * If we don't have stored data to work from, read a SSL/TLS record first
394 * (possibly multiple records if we still don't have anything to return).
396 * This function must handle any surprises the peer may have for us, such as
397 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
398 * a surprise, but handled as if it were), or renegotiation requests.
399 * Also if record payloads contain fragments too small to process, we store
400 * them until there is enough for the respective protocol (the record protocol
401 * may use arbitrary fragmentation and even interleaving):
402 * Change cipher spec protocol
403 * just 1 byte needed, no need for keeping anything stored
405 * 2 bytes needed (AlertLevel, AlertDescription)
407 * 4 bytes needed (HandshakeType, uint24 length) -- we just have
408 * to detect unexpected Client Hello and Hello Request messages
409 * here, anything else is handled by higher layers
410 * Application data protocol
411 * none of our business
413 int dtls1_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
418 void (*cb) (const SSL *ssl, int type2, int val) = NULL;
420 if (!SSL3_BUFFER_is_initialised(&s->rlayer.rbuf)) {
421 /* Not initialized yet */
422 if (!ssl3_setup_buffers(s))
426 if ((type && (type != SSL3_RT_APPLICATION_DATA) &&
427 (type != SSL3_RT_HANDSHAKE)) ||
428 (peek && (type != SSL3_RT_APPLICATION_DATA))) {
429 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
434 * check whether there's a handshake message (client hello?) waiting
436 if ((ret = have_handshake_fragment(s, type, buf, len, peek)))
440 * Now s->rlayer.d->handshake_fragment_len == 0 if
441 * type == SSL3_RT_HANDSHAKE.
444 #ifndef OPENSSL_NO_SCTP
446 * Continue handshake if it had to be interrupted to read app data with
449 if ((!s->in_handshake && SSL_in_init(s)) ||
450 (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
451 (s->state == DTLS1_SCTP_ST_SR_READ_SOCK
452 || s->state == DTLS1_SCTP_ST_CR_READ_SOCK)
453 && s->s3->in_read_app_data != 2))
455 if (!s->in_handshake && SSL_in_init(s))
458 /* type == SSL3_RT_APPLICATION_DATA */
459 i = s->handshake_func(s);
463 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
469 s->rwstate = SSL_NOTHING;
472 * s->s3->rrec.type - is the type of record
473 * s->s3->rrec.data, - data
474 * s->s3->rrec.off, - offset into 'data' for next read
475 * s->s3->rrec.length, - number of bytes.
477 rr = &s->rlayer.rrec;
480 * We are not handshaking and have no data yet, so process data buffered
481 * during the last handshake in advance, if any.
483 if (s->state == SSL_ST_OK && rr->length == 0) {
485 item = pqueue_pop(s->rlayer.d->buffered_app_data.q);
487 #ifndef OPENSSL_NO_SCTP
488 /* Restore bio_dgram_sctp_rcvinfo struct */
489 if (BIO_dgram_is_sctp(SSL_get_rbio(s))) {
490 DTLS1_RECORD_DATA *rdata = (DTLS1_RECORD_DATA *)item->data;
491 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_SET_RCVINFO,
492 sizeof(rdata->recordinfo), &rdata->recordinfo);
496 dtls1_copy_record(s, item);
498 OPENSSL_free(item->data);
503 /* Check for timeout */
504 if (dtls1_handle_timeout(s) > 0)
507 /* get new packet if necessary */
508 if ((rr->length == 0) || (s->rlayer.rstate == SSL_ST_READ_BODY)) {
509 ret = dtls1_get_record(s);
511 ret = dtls1_read_failed(s, ret);
512 /* anything other than a timeout is an error */
520 if (s->d1->listen && rr->type != SSL3_RT_HANDSHAKE) {
525 /* we now have a packet which can be read and processed */
527 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
528 * reset by ssl3_get_finished */
529 && (rr->type != SSL3_RT_HANDSHAKE)) {
531 * We now have application data between CCS and Finished. Most likely
532 * the packets were reordered on their way, so buffer the application
533 * data for later processing rather than dropping the connection.
535 if (dtls1_buffer_record(s, &(s->rlayer.d->buffered_app_data),
537 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
545 * If the other end has shut down, throw anything we read away (even in
548 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) {
550 s->rwstate = SSL_NOTHING;
554 if (type == rr->type) { /* SSL3_RT_APPLICATION_DATA or
555 * SSL3_RT_HANDSHAKE */
557 * make sure that we are not getting application data when we are
558 * doing a handshake for the first time
560 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
561 (s->enc_read_ctx == NULL)) {
562 al = SSL_AD_UNEXPECTED_MESSAGE;
563 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_APP_DATA_IN_HANDSHAKE);
570 if ((unsigned int)len > rr->length)
573 n = (unsigned int)len;
575 memcpy(buf, &(rr->data[rr->off]), n);
579 if (rr->length == 0) {
580 s->rlayer.rstate = SSL_ST_READ_HEADER;
584 #ifndef OPENSSL_NO_SCTP
586 * We were about to renegotiate but had to read belated application
587 * data first, so retry.
589 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
590 rr->type == SSL3_RT_APPLICATION_DATA &&
591 (s->state == DTLS1_SCTP_ST_SR_READ_SOCK
592 || s->state == DTLS1_SCTP_ST_CR_READ_SOCK)) {
593 s->rwstate = SSL_READING;
594 BIO_clear_retry_flags(SSL_get_rbio(s));
595 BIO_set_retry_read(SSL_get_rbio(s));
599 * We might had to delay a close_notify alert because of reordered
600 * app data. If there was an alert and there is no message to read
601 * anymore, finally set shutdown.
603 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
604 s->d1->shutdown_received
605 && !BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) {
606 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
614 * If we get here, then type != rr->type; if we have a handshake message,
615 * then it was unexpected (Hello Request or Client Hello).
619 * In case of record types for which we have 'fragment' storage, fill
620 * that so that we can process the data at a fixed place.
623 unsigned int k, dest_maxlen = 0;
624 unsigned char *dest = NULL;
625 unsigned int *dest_len = NULL;
627 if (rr->type == SSL3_RT_HANDSHAKE) {
628 dest_maxlen = sizeof s->rlayer.d->handshake_fragment;
629 dest = s->rlayer.d->handshake_fragment;
630 dest_len = &s->rlayer.d->handshake_fragment_len;
631 } else if (rr->type == SSL3_RT_ALERT) {
632 dest_maxlen = sizeof(s->rlayer.d->alert_fragment);
633 dest = s->rlayer.d->alert_fragment;
634 dest_len = &s->rlayer.d->alert_fragment_len;
636 #ifndef OPENSSL_NO_HEARTBEATS
637 else if (rr->type == TLS1_RT_HEARTBEAT) {
638 /* We allow a 0 return */
639 if(dtls1_process_heartbeat(s, SSL3_RECORD_get_data(&s->rlayer.rrec),
640 SSL3_RECORD_get_length(&s->rlayer.rrec)) < 0) {
643 /* Exit and notify application to read again */
645 s->rwstate = SSL_READING;
646 BIO_clear_retry_flags(SSL_get_rbio(s));
647 BIO_set_retry_read(SSL_get_rbio(s));
651 /* else it's a CCS message, or application data or wrong */
652 else if (rr->type != SSL3_RT_CHANGE_CIPHER_SPEC) {
654 * Application data while renegotiating is allowed. Try again
657 if (rr->type == SSL3_RT_APPLICATION_DATA) {
659 s->s3->in_read_app_data = 2;
660 bio = SSL_get_rbio(s);
661 s->rwstate = SSL_READING;
662 BIO_clear_retry_flags(bio);
663 BIO_set_retry_read(bio);
667 /* Not certain if this is the right error handling */
668 al = SSL_AD_UNEXPECTED_MESSAGE;
669 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
673 if (dest_maxlen > 0) {
675 * XDTLS: In a pathalogical case, the Client Hello may be
676 * fragmented--don't always expect dest_maxlen bytes
678 if (rr->length < dest_maxlen) {
679 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
681 * for normal alerts rr->length is 2, while
682 * dest_maxlen is 7 if we were to handle this
683 * non-existing alert...
687 s->rlayer.rstate = SSL_ST_READ_HEADER;
692 /* now move 'n' bytes: */
693 for (k = 0; k < dest_maxlen; k++) {
694 dest[k] = rr->data[rr->off++];
697 *dest_len = dest_maxlen;
702 * s->rlayer.d->handshake_fragment_len == 12 iff rr->type == SSL3_RT_HANDSHAKE;
703 * s->rlayer.d->alert_fragment_len == 7 iff rr->type == SSL3_RT_ALERT.
704 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.)
707 /* If we are a client, check for an incoming 'Hello Request': */
709 (s->rlayer.d->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
710 (s->rlayer.d->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
711 (s->session != NULL) && (s->session->cipher != NULL)) {
712 s->rlayer.d->handshake_fragment_len = 0;
714 if ((s->rlayer.d->handshake_fragment[1] != 0) ||
715 (s->rlayer.d->handshake_fragment[2] != 0) ||
716 (s->rlayer.d->handshake_fragment[3] != 0)) {
717 al = SSL_AD_DECODE_ERROR;
718 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_BAD_HELLO_REQUEST);
723 * no need to check sequence number on HELLO REQUEST messages
727 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
728 s->rlayer.d->handshake_fragment, 4, s,
729 s->msg_callback_arg);
731 if (SSL_is_init_finished(s) &&
732 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
733 !s->s3->renegotiate) {
734 s->d1->handshake_read_seq++;
737 if (ssl3_renegotiate_check(s)) {
738 i = s->handshake_func(s);
742 SSLerr(SSL_F_DTLS1_READ_BYTES,
743 SSL_R_SSL_HANDSHAKE_FAILURE);
747 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
748 if (SSL3_BUFFER_get_left(&s->rlayer.rbuf) == 0) {
749 /* no read-ahead left? */
752 * In the case where we try to read application data,
753 * but we trigger an SSL handshake, we return -1 with
754 * the retry option set. Otherwise renegotiation may
755 * cause nasty problems in the blocking world
757 s->rwstate = SSL_READING;
758 bio = SSL_get_rbio(s);
759 BIO_clear_retry_flags(bio);
760 BIO_set_retry_read(bio);
767 * we either finished a handshake or ignored the request, now try
768 * again to obtain the (application) data we were asked for
773 if (s->rlayer.d->alert_fragment_len >= DTLS1_AL_HEADER_LENGTH) {
774 int alert_level = s->rlayer.d->alert_fragment[0];
775 int alert_descr = s->rlayer.d->alert_fragment[1];
777 s->rlayer.d->alert_fragment_len = 0;
780 s->msg_callback(0, s->version, SSL3_RT_ALERT,
781 s->rlayer.d->alert_fragment, 2, s,
782 s->msg_callback_arg);
784 if (s->info_callback != NULL)
785 cb = s->info_callback;
786 else if (s->ctx->info_callback != NULL)
787 cb = s->ctx->info_callback;
790 j = (alert_level << 8) | alert_descr;
791 cb(s, SSL_CB_READ_ALERT, j);
794 if (alert_level == SSL3_AL_WARNING) {
795 s->s3->warn_alert = alert_descr;
796 if (alert_descr == SSL_AD_CLOSE_NOTIFY) {
797 #ifndef OPENSSL_NO_SCTP
799 * With SCTP and streams the socket may deliver app data
800 * after a close_notify alert. We have to check this first so
801 * that nothing gets discarded.
803 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
804 BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) {
805 s->d1->shutdown_received = 1;
806 s->rwstate = SSL_READING;
807 BIO_clear_retry_flags(SSL_get_rbio(s));
808 BIO_set_retry_read(SSL_get_rbio(s));
812 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
816 /* XXX: this is a possible improvement in the future */
817 /* now check if it's a missing record */
818 if (alert_descr == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE) {
820 unsigned int frag_off;
821 unsigned char *p = &(s->rlayer.d->alert_fragment[2]);
826 dtls1_retransmit_message(s,
827 dtls1_get_queue_priority
828 (frag->msg_header.seq, 0), frag_off,
830 if (!found && SSL_in_init(s)) {
832 * fprintf( stderr,"in init = %d\n", SSL_in_init(s));
835 * requested a message not yet sent, send an alert
838 ssl3_send_alert(s, SSL3_AL_WARNING,
839 DTLS1_AD_MISSING_HANDSHAKE_MESSAGE);
843 } else if (alert_level == SSL3_AL_FATAL) {
846 s->rwstate = SSL_NOTHING;
847 s->s3->fatal_alert = alert_descr;
848 SSLerr(SSL_F_DTLS1_READ_BYTES,
849 SSL_AD_REASON_OFFSET + alert_descr);
850 BIO_snprintf(tmp, sizeof tmp, "%d", alert_descr);
851 ERR_add_error_data(2, "SSL alert number ", tmp);
852 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
853 SSL_CTX_remove_session(s->ctx, s->session);
856 al = SSL_AD_ILLEGAL_PARAMETER;
857 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNKNOWN_ALERT_TYPE);
864 if (s->shutdown & SSL_SENT_SHUTDOWN) { /* but we have not received a
866 s->rwstate = SSL_NOTHING;
871 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) {
872 struct ccs_header_st ccs_hdr;
873 unsigned int ccs_hdr_len = DTLS1_CCS_HEADER_LENGTH;
875 dtls1_get_ccs_header(rr->data, &ccs_hdr);
877 if (s->version == DTLS1_BAD_VER)
881 * 'Change Cipher Spec' is just a single byte, so we know exactly
882 * what the record payload has to look like
884 /* XDTLS: check that epoch is consistent */
885 if ((rr->length != ccs_hdr_len) ||
886 (rr->off != 0) || (rr->data[0] != SSL3_MT_CCS)) {
887 i = SSL_AD_ILLEGAL_PARAMETER;
888 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_BAD_CHANGE_CIPHER_SPEC);
895 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC,
896 rr->data, 1, s, s->msg_callback_arg);
899 * We can't process a CCS now, because previous handshake messages
900 * are still missing, so just drop it.
902 if (!s->d1->change_cipher_spec_ok) {
906 s->d1->change_cipher_spec_ok = 0;
908 s->s3->change_cipher_spec = 1;
909 if (!ssl3_do_change_cipher_spec(s))
912 /* do this whenever CCS is processed */
913 dtls1_reset_seq_numbers(s, SSL3_CC_READ);
915 if (s->version == DTLS1_BAD_VER)
916 s->d1->handshake_read_seq++;
918 #ifndef OPENSSL_NO_SCTP
920 * Remember that a CCS has been received, so that an old key of
921 * SCTP-Auth can be deleted when a CCS is sent. Will be ignored if no
924 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD, 1, NULL);
931 * Unexpected handshake message (Client Hello, or protocol violation)
933 if ((s->rlayer.d->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
935 struct hm_header_st msg_hdr;
937 /* this may just be a stale retransmit */
938 dtls1_get_message_header(rr->data, &msg_hdr);
939 if (rr->epoch != s->rlayer.d->r_epoch) {
945 * If we are server, we may have a repeated FINISHED of the client
946 * here, then retransmit our CCS and FINISHED.
948 if (msg_hdr.type == SSL3_MT_FINISHED) {
949 if (dtls1_check_timeout_num(s) < 0)
952 dtls1_retransmit_buffered_messages(s);
957 if (((s->state & SSL_ST_MASK) == SSL_ST_OK) &&
958 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) {
959 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
963 i = s->handshake_func(s);
967 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
971 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
972 if (SSL3_BUFFER_get_left(&s->rlayer.rbuf) == 0) {
973 /* no read-ahead left? */
976 * In the case where we try to read application data, but we
977 * trigger an SSL handshake, we return -1 with the retry
978 * option set. Otherwise renegotiation may cause nasty
979 * problems in the blocking world
981 s->rwstate = SSL_READING;
982 bio = SSL_get_rbio(s);
983 BIO_clear_retry_flags(bio);
984 BIO_set_retry_read(bio);
993 /* TLS just ignores unknown message types */
994 if (s->version == TLS1_VERSION) {
998 al = SSL_AD_UNEXPECTED_MESSAGE;
999 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
1001 case SSL3_RT_CHANGE_CIPHER_SPEC:
1003 case SSL3_RT_HANDSHAKE:
1005 * we already handled all of these, with the possible exception of
1006 * SSL3_RT_HANDSHAKE when s->in_handshake is set, but that should not
1007 * happen when type != rr->type
1009 al = SSL_AD_UNEXPECTED_MESSAGE;
1010 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
1012 case SSL3_RT_APPLICATION_DATA:
1014 * At this point, we were expecting handshake data, but have
1015 * application data. If the library was running inside ssl3_read()
1016 * (i.e. in_read_app_data is set) and it makes sense to read
1017 * application data at this point (session renegotiation not yet
1018 * started), we will indulge it.
1020 if (s->s3->in_read_app_data &&
1021 (s->s3->total_renegotiations != 0) &&
1022 (((s->state & SSL_ST_CONNECT) &&
1023 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1024 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1025 ) || ((s->state & SSL_ST_ACCEPT) &&
1026 (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1027 (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1030 s->s3->in_read_app_data = 2;
1033 al = SSL_AD_UNEXPECTED_MESSAGE;
1034 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
1041 ssl3_send_alert(s, SSL3_AL_FATAL, al);
1048 * this only happens when a client hello is received and a handshake
1051 static int have_handshake_fragment(SSL *s, int type, unsigned char *buf,
1055 if ((type == SSL3_RT_HANDSHAKE)
1056 && (s->rlayer.d->handshake_fragment_len > 0))
1057 /* (partially) satisfy request from storage */
1059 unsigned char *src = s->rlayer.d->handshake_fragment;
1060 unsigned char *dst = buf;
1065 while ((len > 0) && (s->rlayer.d->handshake_fragment_len > 0)) {
1068 s->rlayer.d->handshake_fragment_len--;
1071 /* move any remaining fragment bytes: */
1072 for (k = 0; k < s->rlayer.d->handshake_fragment_len; k++)
1073 s->rlayer.d->handshake_fragment[k] = *src++;
1081 * Call this to write data in records of type 'type' It will return <= 0 if
1082 * not all data has been sent or non-blocking IO.
1084 int dtls1_write_bytes(SSL *s, int type, const void *buf, int len)
1088 OPENSSL_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH);
1089 s->rwstate = SSL_NOTHING;
1090 i = do_dtls1_write(s, type, buf, len, 0);
1094 int do_dtls1_write(SSL *s, int type, const unsigned char *buf,
1095 unsigned int len, int create_empty_fragment)
1097 unsigned char *p, *pseq;
1098 int i, mac_size, clear = 0;
1105 wb = &s->rlayer.wbuf;
1108 * first check if there is a SSL3_BUFFER still being written out. This
1109 * will happen with non blocking IO
1111 if (SSL3_BUFFER_get_left(wb) != 0) {
1112 OPENSSL_assert(0); /* XDTLS: want to see if we ever get here */
1113 return (ssl3_write_pending(s, type, buf, len));
1116 /* If we have an alert to send, lets send it */
1117 if (s->s3->alert_dispatch) {
1118 i = s->method->ssl_dispatch_alert(s);
1121 /* if it went, fall through and send more stuff */
1124 if (len == 0 && !create_empty_fragment)
1127 wr = &s->rlayer.wrec;
1130 if ((sess == NULL) ||
1131 (s->enc_write_ctx == NULL) || (EVP_MD_CTX_md(s->write_hash) == NULL))
1137 mac_size = EVP_MD_CTX_size(s->write_hash);
1142 p = wb->buf + prefix_len;
1144 /* write the header */
1146 *(p++) = type & 0xff;
1149 * Special case: for hello verify request, client version 1.0 and we
1150 * haven't decided which version to use yet send back using version 1.0
1151 * header: otherwise some clients will ignore it.
1153 if (s->method->version == DTLS_ANY_VERSION) {
1154 *(p++) = DTLS1_VERSION >> 8;
1155 *(p++) = DTLS1_VERSION & 0xff;
1157 *(p++) = s->version >> 8;
1158 *(p++) = s->version & 0xff;
1161 /* field where we are to write out packet epoch, seq num and len */
1165 /* Explicit IV length, block ciphers appropriate version flag */
1166 if (s->enc_write_ctx) {
1167 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
1168 if (mode == EVP_CIPH_CBC_MODE) {
1169 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
1173 /* Need explicit part of IV for GCM mode */
1174 else if (mode == EVP_CIPH_GCM_MODE)
1175 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
1181 /* lets setup the record stuff. */
1182 wr->data = p + eivlen; /* make room for IV in case of CBC */
1183 wr->length = (int)len;
1184 wr->input = (unsigned char *)buf;
1187 * we now 'read' from wr->input, wr->length bytes into wr->data
1190 /* first we compress */
1191 if (s->compress != NULL) {
1192 if (!ssl3_do_compress(s)) {
1193 SSLerr(SSL_F_DO_DTLS1_WRITE, SSL_R_COMPRESSION_FAILURE);
1197 memcpy(wr->data, wr->input, wr->length);
1198 wr->input = wr->data;
1202 * we should still have the output to wr->data and the input from
1203 * wr->input. Length should be wr->length. wr->data still points in the
1207 if (mac_size != 0) {
1208 if (s->method->ssl3_enc->mac(s, &(p[wr->length + eivlen]), 1) < 0)
1210 wr->length += mac_size;
1213 /* this is true regardless of mac size */
1218 wr->length += eivlen;
1220 if (s->method->ssl3_enc->enc(s, 1) < 1)
1223 /* record length after mac and block padding */
1225 * if (type == SSL3_RT_APPLICATION_DATA || (type == SSL3_RT_ALERT && !
1229 /* there's only one epoch between handshake and app data */
1231 s2n(s->rlayer.d->w_epoch, pseq);
1235 * else s2n(s->d1->handshake_epoch, pseq);
1238 memcpy(pseq, &(s->rlayer.write_sequence[2]), 6);
1240 s2n(wr->length, pseq);
1242 if (s->msg_callback)
1243 s->msg_callback(1, 0, SSL3_RT_HEADER, pseq - DTLS1_RT_HEADER_LENGTH,
1244 DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg);
1247 * we should now have wr->data pointing to the encrypted data, which is
1250 wr->type = type; /* not needed but helps for debugging */
1251 wr->length += DTLS1_RT_HEADER_LENGTH;
1253 ssl3_record_sequence_update(&(s->rlayer.write_sequence[0]));
1255 if (create_empty_fragment) {
1257 * we are in a recursive call; just return the length, don't write
1263 /* now let's set up wb */
1264 wb->left = prefix_len + wr->length;
1268 * memorize arguments so that ssl3_write_pending can detect bad write
1271 s->rlayer.wpend_tot = len;
1272 s->rlayer.wpend_buf = buf;
1273 s->rlayer.wpend_type = type;
1274 s->rlayer.wpend_ret = len;
1276 /* we now just need to write the buffer */
1277 return ssl3_write_pending(s, type, buf, len);
1282 DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr,
1283 unsigned int *is_next_epoch)
1288 /* In current epoch, accept HM, CCS, DATA, & ALERT */
1289 if (rr->epoch == s->rlayer.d->r_epoch)
1290 return &s->rlayer.d->bitmap;
1292 /* Only HM and ALERT messages can be from the next epoch */
1293 else if (rr->epoch == (unsigned long)(s->rlayer.d->r_epoch + 1) &&
1294 (rr->type == SSL3_RT_HANDSHAKE || rr->type == SSL3_RT_ALERT)) {
1296 return &s->rlayer.d->next_bitmap;
1302 void dtls1_reset_seq_numbers(SSL *s, int rw)
1305 unsigned int seq_bytes = sizeof(s->rlayer.read_sequence);
1307 if (rw & SSL3_CC_READ) {
1308 seq = s->rlayer.read_sequence;
1309 s->rlayer.d->r_epoch++;
1310 memcpy(&(s->rlayer.d->bitmap), &(s->rlayer.d->next_bitmap),
1311 sizeof(DTLS1_BITMAP));
1312 memset(&(s->rlayer.d->next_bitmap), 0x00, sizeof(DTLS1_BITMAP));
1314 seq = s->rlayer.write_sequence;
1315 memcpy(s->rlayer.d->last_write_sequence, seq,
1316 sizeof(s->rlayer.write_sequence));
1317 s->rlayer.d->w_epoch++;
1320 memset(seq, 0x00, seq_bytes);