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/rand.h>
123 #include "record_locl.h"
125 int DTLS_RECORD_LAYER_new(RECORD_LAYER *rl)
127 DTLS_RECORD_LAYER *d;
129 if ((d = OPENSSL_malloc(sizeof(*d))) == NULL)
135 d->unprocessed_rcds.q = pqueue_new();
136 d->processed_rcds.q = pqueue_new();
137 d->buffered_app_data.q = pqueue_new();
139 if (d->unprocessed_rcds.q == NULL || d->processed_rcds.q == NULL
140 || d->buffered_app_data.q == NULL) {
141 pqueue_free(d->unprocessed_rcds.q);
142 pqueue_free(d->processed_rcds.q);
143 pqueue_free(d->buffered_app_data.q);
152 void DTLS_RECORD_LAYER_free(RECORD_LAYER *rl)
154 DTLS_RECORD_LAYER_clear(rl);
155 pqueue_free(rl->d->unprocessed_rcds.q);
156 pqueue_free(rl->d->processed_rcds.q);
157 pqueue_free(rl->d->buffered_app_data.q);
162 void DTLS_RECORD_LAYER_clear(RECORD_LAYER *rl)
164 DTLS_RECORD_LAYER *d;
166 DTLS1_RECORD_DATA *rdata;
167 pqueue *unprocessed_rcds;
168 pqueue *processed_rcds;
169 pqueue *buffered_app_data;
173 while ((item = pqueue_pop(d->unprocessed_rcds.q)) != NULL) {
174 rdata = (DTLS1_RECORD_DATA *)item->data;
175 OPENSSL_free(rdata->rbuf.buf);
176 OPENSSL_free(item->data);
180 while ((item = pqueue_pop(d->processed_rcds.q)) != NULL) {
181 rdata = (DTLS1_RECORD_DATA *)item->data;
182 OPENSSL_free(rdata->rbuf.buf);
183 OPENSSL_free(item->data);
187 while ((item = pqueue_pop(d->buffered_app_data.q)) != NULL) {
188 rdata = (DTLS1_RECORD_DATA *)item->data;
189 OPENSSL_free(rdata->rbuf.buf);
190 OPENSSL_free(item->data);
194 unprocessed_rcds = d->unprocessed_rcds.q;
195 processed_rcds = d->processed_rcds.q;
196 buffered_app_data = d->buffered_app_data.q;
197 memset(d, 0, sizeof(*d));
198 d->unprocessed_rcds.q = unprocessed_rcds;
199 d->processed_rcds.q = processed_rcds;
200 d->buffered_app_data.q = buffered_app_data;
203 void DTLS_RECORD_LAYER_set_saved_w_epoch(RECORD_LAYER *rl, unsigned short e)
205 if (e == rl->d->w_epoch - 1) {
206 memcpy(rl->d->curr_write_sequence,
208 sizeof(rl->write_sequence));
209 memcpy(rl->write_sequence,
210 rl->d->last_write_sequence,
211 sizeof(rl->write_sequence));
212 } else if (e == rl->d->w_epoch + 1) {
213 memcpy(rl->d->last_write_sequence,
215 sizeof(unsigned char[8]));
216 memcpy(rl->write_sequence,
217 rl->d->curr_write_sequence,
218 sizeof(rl->write_sequence));
223 void DTLS_RECORD_LAYER_resync_write(RECORD_LAYER *rl)
225 memcpy(rl->write_sequence, rl->read_sequence, sizeof(rl->write_sequence));
229 void DTLS_RECORD_LAYER_set_write_sequence(RECORD_LAYER *rl, unsigned char *seq)
231 memcpy(rl->write_sequence, seq, SEQ_NUM_SIZE);
234 static int have_handshake_fragment(SSL *s, int type, unsigned char *buf,
237 /* copy buffered record into SSL structure */
238 static int dtls1_copy_record(SSL *s, pitem *item)
240 DTLS1_RECORD_DATA *rdata;
242 rdata = (DTLS1_RECORD_DATA *)item->data;
244 SSL3_BUFFER_release(&s->rlayer.rbuf);
246 s->rlayer.packet = rdata->packet;
247 s->rlayer.packet_length = rdata->packet_length;
248 memcpy(&s->rlayer.rbuf, &(rdata->rbuf), sizeof(SSL3_BUFFER));
249 memcpy(&s->rlayer.rrec, &(rdata->rrec), sizeof(SSL3_RECORD));
251 /* Set proper sequence number for mac calculation */
252 memcpy(&(s->rlayer.read_sequence[2]), &(rdata->packet[5]), 6);
257 int dtls1_buffer_record(SSL *s, record_pqueue *queue, unsigned char *priority)
259 DTLS1_RECORD_DATA *rdata;
262 /* Limit the size of the queue to prevent DOS attacks */
263 if (pqueue_size(queue->q) >= 100)
266 rdata = OPENSSL_malloc(sizeof(*rdata));
267 item = pitem_new(priority, rdata);
268 if (rdata == NULL || item == NULL) {
271 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
275 rdata->packet = s->rlayer.packet;
276 rdata->packet_length = s->rlayer.packet_length;
277 memcpy(&(rdata->rbuf), &s->rlayer.rbuf, sizeof(SSL3_BUFFER));
278 memcpy(&(rdata->rrec), &s->rlayer.rrec, sizeof(SSL3_RECORD));
282 #ifndef OPENSSL_NO_SCTP
283 /* Store bio_dgram_sctp_rcvinfo struct */
284 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
285 (SSL_get_state(s) == TLS_ST_SR_FINISHED
286 || SSL_get_state(s) == TLS_ST_CR_FINISHED)) {
287 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_GET_RCVINFO,
288 sizeof(rdata->recordinfo), &rdata->recordinfo);
292 s->rlayer.packet = NULL;
293 s->rlayer.packet_length = 0;
294 memset(&s->rlayer.rbuf, 0, sizeof(s->rlayer.rbuf));
295 memset(&s->rlayer.rrec, 0, sizeof(s->rlayer.rrec));
297 if (!ssl3_setup_buffers(s)) {
298 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
299 OPENSSL_free(rdata->rbuf.buf);
305 /* insert should not fail, since duplicates are dropped */
306 if (pqueue_insert(queue->q, item) == NULL) {
307 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
308 OPENSSL_free(rdata->rbuf.buf);
317 int dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue)
321 item = pqueue_pop(queue->q);
323 dtls1_copy_record(s, item);
325 OPENSSL_free(item->data);
335 * retrieve a buffered record that belongs to the new epoch, i.e., not
338 #define dtls1_get_unprocessed_record(s) \
339 dtls1_retrieve_buffered_record((s), \
340 &((s)->rlayer.d->unprocessed_rcds))
343 int dtls1_process_buffered_records(SSL *s)
347 item = pqueue_peek(s->rlayer.d->unprocessed_rcds.q);
349 /* Check if epoch is current. */
350 if (s->rlayer.d->unprocessed_rcds.epoch != s->rlayer.d->r_epoch)
351 return (1); /* Nothing to do. */
353 /* Process all the records. */
354 while (pqueue_peek(s->rlayer.d->unprocessed_rcds.q)) {
355 dtls1_get_unprocessed_record(s);
356 if (!dtls1_process_record(s))
358 if (dtls1_buffer_record(s, &(s->rlayer.d->processed_rcds),
359 SSL3_RECORD_get_seq_num(&s->rlayer.rrec)) < 0)
365 * sync epoch numbers once all the unprocessed records have been
368 s->rlayer.d->processed_rcds.epoch = s->rlayer.d->r_epoch;
369 s->rlayer.d->unprocessed_rcds.epoch = s->rlayer.d->r_epoch + 1;
376 * Return up to 'len' payload bytes received in 'type' records.
377 * 'type' is one of the following:
379 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
380 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
381 * - 0 (during a shutdown, no data has to be returned)
383 * If we don't have stored data to work from, read a SSL/TLS record first
384 * (possibly multiple records if we still don't have anything to return).
386 * This function must handle any surprises the peer may have for us, such as
387 * Alert records (e.g. close_notify) or renegotiation requests. ChangeCipherSpec
388 * messages are treated as if they were handshake messages *if* the |recd_type|
389 * argument is non NULL.
390 * Also if record payloads contain fragments too small to process, we store
391 * them until there is enough for the respective protocol (the record protocol
392 * may use arbitrary fragmentation and even interleaving):
393 * Change cipher spec protocol
394 * just 1 byte needed, no need for keeping anything stored
396 * 2 bytes needed (AlertLevel, AlertDescription)
398 * 4 bytes needed (HandshakeType, uint24 length) -- we just have
399 * to detect unexpected Client Hello and Hello Request messages
400 * here, anything else is handled by higher layers
401 * Application data protocol
402 * none of our business
404 int dtls1_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf,
410 void (*cb) (const SSL *ssl, int type2, int val) = NULL;
412 if (!SSL3_BUFFER_is_initialised(&s->rlayer.rbuf)) {
413 /* Not initialized yet */
414 if (!ssl3_setup_buffers(s))
418 if ((type && (type != SSL3_RT_APPLICATION_DATA) &&
419 (type != SSL3_RT_HANDSHAKE)) ||
420 (peek && (type != SSL3_RT_APPLICATION_DATA))) {
421 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
426 * check whether there's a handshake message (client hello?) waiting
428 if ((ret = have_handshake_fragment(s, type, buf, len, peek)))
432 * Now s->rlayer.d->handshake_fragment_len == 0 if
433 * type == SSL3_RT_HANDSHAKE.
436 #ifndef OPENSSL_NO_SCTP
438 * Continue handshake if it had to be interrupted to read app data with
441 if ((!ossl_statem_get_in_handshake(s) && SSL_in_init(s)) ||
442 (BIO_dgram_is_sctp(SSL_get_rbio(s))
443 && ossl_statem_in_sctp_read_sock(s)
444 && s->s3->in_read_app_data != 2))
446 if (!ossl_statem_get_in_handshake(s) && SSL_in_init(s))
449 /* type == SSL3_RT_APPLICATION_DATA */
450 i = s->handshake_func(s);
454 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
460 s->rwstate = SSL_NOTHING;
463 * s->s3->rrec.type - is the type of record
464 * s->s3->rrec.data, - data
465 * s->s3->rrec.off, - offset into 'data' for next read
466 * s->s3->rrec.length, - number of bytes.
468 rr = &s->rlayer.rrec;
471 * We are not handshaking and have no data yet, so process data buffered
472 * during the last handshake in advance, if any.
474 if (SSL_is_init_finished(s) && SSL3_RECORD_get_length(rr) == 0) {
476 item = pqueue_pop(s->rlayer.d->buffered_app_data.q);
478 #ifndef OPENSSL_NO_SCTP
479 /* Restore bio_dgram_sctp_rcvinfo struct */
480 if (BIO_dgram_is_sctp(SSL_get_rbio(s))) {
481 DTLS1_RECORD_DATA *rdata = (DTLS1_RECORD_DATA *)item->data;
482 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_SET_RCVINFO,
483 sizeof(rdata->recordinfo), &rdata->recordinfo);
487 dtls1_copy_record(s, item);
489 OPENSSL_free(item->data);
494 /* Check for timeout */
495 if (dtls1_handle_timeout(s) > 0)
498 /* get new packet if necessary */
499 if ((SSL3_RECORD_get_length(rr) == 0)
500 || (s->rlayer.rstate == SSL_ST_READ_BODY)) {
501 ret = dtls1_get_record(s);
503 ret = dtls1_read_failed(s, ret);
504 /* anything other than a timeout is an error */
512 /* we now have a packet which can be read and processed */
514 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
515 * reset by ssl3_get_finished */
516 && (SSL3_RECORD_get_type(rr) != SSL3_RT_HANDSHAKE)) {
518 * We now have application data between CCS and Finished. Most likely
519 * the packets were reordered on their way, so buffer the application
520 * data for later processing rather than dropping the connection.
522 if (dtls1_buffer_record(s, &(s->rlayer.d->buffered_app_data),
523 SSL3_RECORD_get_seq_num(rr)) < 0) {
524 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
527 SSL3_RECORD_set_length(rr, 0);
532 * If the other end has shut down, throw anything we read away (even in
535 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) {
536 SSL3_RECORD_set_length(rr, 0);
537 s->rwstate = SSL_NOTHING;
541 if (type == SSL3_RECORD_get_type(rr)
542 || (SSL3_RECORD_get_type(rr) == SSL3_RT_CHANGE_CIPHER_SPEC
543 && type == SSL3_RT_HANDSHAKE && recvd_type != NULL)) {
545 * SSL3_RT_APPLICATION_DATA or
546 * SSL3_RT_HANDSHAKE or
547 * SSL3_RT_CHANGE_CIPHER_SPEC
550 * make sure that we are not getting application data when we are
551 * doing a handshake for the first time
553 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
554 (s->enc_read_ctx == NULL)) {
555 al = SSL_AD_UNEXPECTED_MESSAGE;
556 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_APP_DATA_IN_HANDSHAKE);
560 if (recvd_type != NULL)
561 *recvd_type = SSL3_RECORD_get_type(rr);
566 if ((unsigned int)len > SSL3_RECORD_get_length(rr))
567 n = SSL3_RECORD_get_length(rr);
569 n = (unsigned int)len;
571 memcpy(buf, &(SSL3_RECORD_get_data(rr)[SSL3_RECORD_get_off(rr)]), n);
573 SSL3_RECORD_add_length(rr, -n);
574 SSL3_RECORD_add_off(rr, n);
575 if (SSL3_RECORD_get_length(rr) == 0) {
576 s->rlayer.rstate = SSL_ST_READ_HEADER;
577 SSL3_RECORD_set_off(rr, 0);
580 #ifndef OPENSSL_NO_SCTP
582 * We were about to renegotiate but had to read belated application
583 * data first, so retry.
585 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
586 SSL3_RECORD_get_type(rr) == SSL3_RT_APPLICATION_DATA &&
587 ossl_statem_in_sctp_read_sock(s)) {
588 s->rwstate = SSL_READING;
589 BIO_clear_retry_flags(SSL_get_rbio(s));
590 BIO_set_retry_read(SSL_get_rbio(s));
594 * We might had to delay a close_notify alert because of reordered
595 * app data. If there was an alert and there is no message to read
596 * anymore, finally set shutdown.
598 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
599 s->d1->shutdown_received
600 && !BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) {
601 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
609 * If we get here, then type != rr->type; if we have a handshake message,
610 * then it was unexpected (Hello Request or Client Hello).
614 * In case of record types for which we have 'fragment' storage, fill
615 * that so that we can process the data at a fixed place.
618 unsigned int k, dest_maxlen = 0;
619 unsigned char *dest = NULL;
620 unsigned int *dest_len = NULL;
622 if (SSL3_RECORD_get_type(rr) == SSL3_RT_HANDSHAKE) {
623 dest_maxlen = sizeof s->rlayer.d->handshake_fragment;
624 dest = s->rlayer.d->handshake_fragment;
625 dest_len = &s->rlayer.d->handshake_fragment_len;
626 } else if (SSL3_RECORD_get_type(rr) == SSL3_RT_ALERT) {
627 dest_maxlen = sizeof(s->rlayer.d->alert_fragment);
628 dest = s->rlayer.d->alert_fragment;
629 dest_len = &s->rlayer.d->alert_fragment_len;
631 #ifndef OPENSSL_NO_HEARTBEATS
632 else if (SSL3_RECORD_get_type(rr) == TLS1_RT_HEARTBEAT) {
633 /* We allow a 0 return */
634 if (dtls1_process_heartbeat(s, SSL3_RECORD_get_data(rr),
635 SSL3_RECORD_get_length(rr)) < 0) {
638 /* Exit and notify application to read again */
639 SSL3_RECORD_set_length(rr, 0);
640 s->rwstate = SSL_READING;
641 BIO_clear_retry_flags(SSL_get_rbio(s));
642 BIO_set_retry_read(SSL_get_rbio(s));
646 /* else it's a CCS message, or application data or wrong */
647 else if (SSL3_RECORD_get_type(rr) != SSL3_RT_CHANGE_CIPHER_SPEC) {
649 * Application data while renegotiating is allowed. Try again
652 if (SSL3_RECORD_get_type(rr) == SSL3_RT_APPLICATION_DATA) {
654 s->s3->in_read_app_data = 2;
655 bio = SSL_get_rbio(s);
656 s->rwstate = SSL_READING;
657 BIO_clear_retry_flags(bio);
658 BIO_set_retry_read(bio);
662 /* Not certain if this is the right error handling */
663 al = SSL_AD_UNEXPECTED_MESSAGE;
664 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
668 if (dest_maxlen > 0) {
670 * XDTLS: In a pathalogical case, the Client Hello may be
671 * fragmented--don't always expect dest_maxlen bytes
673 if (SSL3_RECORD_get_length(rr) < dest_maxlen) {
674 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
676 * for normal alerts rr->length is 2, while
677 * dest_maxlen is 7 if we were to handle this
678 * non-existing alert...
682 s->rlayer.rstate = SSL_ST_READ_HEADER;
683 SSL3_RECORD_set_length(rr, 0);
687 /* now move 'n' bytes: */
688 for (k = 0; k < dest_maxlen; k++) {
689 dest[k] = SSL3_RECORD_get_data(rr)[SSL3_RECORD_get_off(rr)];
690 SSL3_RECORD_add_off(rr, 1);
691 SSL3_RECORD_add_length(rr, -1);
693 *dest_len = dest_maxlen;
698 * s->rlayer.d->handshake_fragment_len == 12 iff rr->type == SSL3_RT_HANDSHAKE;
699 * s->rlayer.d->alert_fragment_len == 7 iff rr->type == SSL3_RT_ALERT.
700 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.)
703 /* If we are a client, check for an incoming 'Hello Request': */
705 (s->rlayer.d->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
706 (s->rlayer.d->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
707 (s->session != NULL) && (s->session->cipher != NULL)) {
708 s->rlayer.d->handshake_fragment_len = 0;
710 if ((s->rlayer.d->handshake_fragment[1] != 0) ||
711 (s->rlayer.d->handshake_fragment[2] != 0) ||
712 (s->rlayer.d->handshake_fragment[3] != 0)) {
713 al = SSL_AD_DECODE_ERROR;
714 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_BAD_HELLO_REQUEST);
719 * no need to check sequence number on HELLO REQUEST messages
723 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
724 s->rlayer.d->handshake_fragment, 4, s,
725 s->msg_callback_arg);
727 if (SSL_is_init_finished(s) &&
728 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
729 !s->s3->renegotiate) {
730 s->d1->handshake_read_seq++;
733 if (ssl3_renegotiate_check(s)) {
734 i = s->handshake_func(s);
738 SSLerr(SSL_F_DTLS1_READ_BYTES,
739 SSL_R_SSL_HANDSHAKE_FAILURE);
743 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
744 if (SSL3_BUFFER_get_left(&s->rlayer.rbuf) == 0) {
745 /* no read-ahead left? */
748 * In the case where we try to read application data,
749 * but we trigger an SSL handshake, we return -1 with
750 * the retry option set. Otherwise renegotiation may
751 * cause nasty problems in the blocking world
753 s->rwstate = SSL_READING;
754 bio = SSL_get_rbio(s);
755 BIO_clear_retry_flags(bio);
756 BIO_set_retry_read(bio);
763 * we either finished a handshake or ignored the request, now try
764 * again to obtain the (application) data we were asked for
769 if (s->rlayer.d->alert_fragment_len >= DTLS1_AL_HEADER_LENGTH) {
770 int alert_level = s->rlayer.d->alert_fragment[0];
771 int alert_descr = s->rlayer.d->alert_fragment[1];
773 s->rlayer.d->alert_fragment_len = 0;
776 s->msg_callback(0, s->version, SSL3_RT_ALERT,
777 s->rlayer.d->alert_fragment, 2, s,
778 s->msg_callback_arg);
780 if (s->info_callback != NULL)
781 cb = s->info_callback;
782 else if (s->ctx->info_callback != NULL)
783 cb = s->ctx->info_callback;
786 j = (alert_level << 8) | alert_descr;
787 cb(s, SSL_CB_READ_ALERT, j);
790 if (alert_level == SSL3_AL_WARNING) {
791 s->s3->warn_alert = alert_descr;
792 if (alert_descr == SSL_AD_CLOSE_NOTIFY) {
793 #ifndef OPENSSL_NO_SCTP
795 * With SCTP and streams the socket may deliver app data
796 * after a close_notify alert. We have to check this first so
797 * that nothing gets discarded.
799 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
800 BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) {
801 s->d1->shutdown_received = 1;
802 s->rwstate = SSL_READING;
803 BIO_clear_retry_flags(SSL_get_rbio(s));
804 BIO_set_retry_read(SSL_get_rbio(s));
808 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
812 /* XXX: this is a possible improvement in the future */
813 /* now check if it's a missing record */
814 if (alert_descr == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE) {
816 unsigned int frag_off;
817 unsigned char *p = &(s->rlayer.d->alert_fragment[2]);
822 dtls1_retransmit_message(s,
823 dtls1_get_queue_priority
824 (frag->msg_header.seq, 0), frag_off,
826 if (!found && SSL_in_init(s)) {
828 * fprintf( stderr,"in init = %d\n", SSL_in_init(s));
831 * requested a message not yet sent, send an alert
834 ssl3_send_alert(s, SSL3_AL_WARNING,
835 DTLS1_AD_MISSING_HANDSHAKE_MESSAGE);
839 } else if (alert_level == SSL3_AL_FATAL) {
842 s->rwstate = SSL_NOTHING;
843 s->s3->fatal_alert = alert_descr;
844 SSLerr(SSL_F_DTLS1_READ_BYTES,
845 SSL_AD_REASON_OFFSET + alert_descr);
846 BIO_snprintf(tmp, sizeof tmp, "%d", alert_descr);
847 ERR_add_error_data(2, "SSL alert number ", tmp);
848 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
849 SSL_CTX_remove_session(s->ctx, s->session);
852 al = SSL_AD_ILLEGAL_PARAMETER;
853 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNKNOWN_ALERT_TYPE);
860 if (s->shutdown & SSL_SENT_SHUTDOWN) { /* but we have not received a
862 s->rwstate = SSL_NOTHING;
863 SSL3_RECORD_set_length(rr, 0);
867 if (SSL3_RECORD_get_type(rr) == SSL3_RT_CHANGE_CIPHER_SPEC) {
869 * We can't process a CCS now, because previous handshake messages
870 * are still missing, so just drop it.
872 SSL3_RECORD_set_length(rr, 0);
877 * Unexpected handshake message (Client Hello, or protocol violation)
879 if ((s->rlayer.d->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
880 !ossl_statem_get_in_handshake(s)) {
881 struct hm_header_st msg_hdr;
883 /* this may just be a stale retransmit */
884 dtls1_get_message_header(rr->data, &msg_hdr);
885 if (SSL3_RECORD_get_epoch(rr) != s->rlayer.d->r_epoch) {
886 SSL3_RECORD_set_length(rr, 0);
891 * If we are server, we may have a repeated FINISHED of the client
892 * here, then retransmit our CCS and FINISHED.
894 if (msg_hdr.type == SSL3_MT_FINISHED) {
895 if (dtls1_check_timeout_num(s) < 0)
898 dtls1_retransmit_buffered_messages(s);
899 SSL3_RECORD_set_length(rr, 0);
903 if (SSL_is_init_finished(s) &&
904 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) {
905 ossl_statem_set_in_init(s, 1);
909 i = s->handshake_func(s);
913 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
917 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
918 if (SSL3_BUFFER_get_left(&s->rlayer.rbuf) == 0) {
919 /* no read-ahead left? */
922 * In the case where we try to read application data, but we
923 * trigger an SSL handshake, we return -1 with the retry
924 * option set. Otherwise renegotiation may cause nasty
925 * problems in the blocking world
927 s->rwstate = SSL_READING;
928 bio = SSL_get_rbio(s);
929 BIO_clear_retry_flags(bio);
930 BIO_set_retry_read(bio);
937 switch (SSL3_RECORD_get_type(rr)) {
939 /* TLS just ignores unknown message types */
940 if (s->version == TLS1_VERSION) {
941 SSL3_RECORD_set_length(rr, 0);
944 al = SSL_AD_UNEXPECTED_MESSAGE;
945 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
947 case SSL3_RT_CHANGE_CIPHER_SPEC:
949 case SSL3_RT_HANDSHAKE:
951 * we already handled all of these, with the possible exception of
952 * SSL3_RT_HANDSHAKE when ossl_statem_get_in_handshake(s) is true, but
953 * that should not happen when type != rr->type
955 al = SSL_AD_UNEXPECTED_MESSAGE;
956 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
958 case SSL3_RT_APPLICATION_DATA:
960 * At this point, we were expecting handshake data, but have
961 * application data. If the library was running inside ssl3_read()
962 * (i.e. in_read_app_data is set) and it makes sense to read
963 * application data at this point (session renegotiation not yet
964 * started), we will indulge it.
966 if (s->s3->in_read_app_data &&
967 (s->s3->total_renegotiations != 0) &&
968 ossl_statem_app_data_allowed(s)) {
969 s->s3->in_read_app_data = 2;
972 al = SSL_AD_UNEXPECTED_MESSAGE;
973 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
980 ssl3_send_alert(s, SSL3_AL_FATAL, al);
986 * this only happens when a client hello is received and a handshake
989 static int have_handshake_fragment(SSL *s, int type, unsigned char *buf,
993 if ((type == SSL3_RT_HANDSHAKE)
994 && (s->rlayer.d->handshake_fragment_len > 0))
995 /* (partially) satisfy request from storage */
997 unsigned char *src = s->rlayer.d->handshake_fragment;
998 unsigned char *dst = buf;
1003 while ((len > 0) && (s->rlayer.d->handshake_fragment_len > 0)) {
1006 s->rlayer.d->handshake_fragment_len--;
1009 /* move any remaining fragment bytes: */
1010 for (k = 0; k < s->rlayer.d->handshake_fragment_len; k++)
1011 s->rlayer.d->handshake_fragment[k] = *src++;
1019 * Call this to write data in records of type 'type' It will return <= 0 if
1020 * not all data has been sent or non-blocking IO.
1022 int dtls1_write_bytes(SSL *s, int type, const void *buf, int len)
1026 OPENSSL_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH);
1027 s->rwstate = SSL_NOTHING;
1028 i = do_dtls1_write(s, type, buf, len, 0);
1032 int do_dtls1_write(SSL *s, int type, const unsigned char *buf,
1033 unsigned int len, int create_empty_fragment)
1035 unsigned char *p, *pseq;
1036 int i, mac_size, clear = 0;
1043 wb = &s->rlayer.wbuf;
1046 * first check if there is a SSL3_BUFFER still being written out. This
1047 * will happen with non blocking IO
1049 if (SSL3_BUFFER_get_left(wb) != 0) {
1050 OPENSSL_assert(0); /* XDTLS: want to see if we ever get here */
1051 return (ssl3_write_pending(s, type, buf, len));
1054 /* If we have an alert to send, lets send it */
1055 if (s->s3->alert_dispatch) {
1056 i = s->method->ssl_dispatch_alert(s);
1059 /* if it went, fall through and send more stuff */
1062 if (len == 0 && !create_empty_fragment)
1065 wr = &s->rlayer.wrec;
1068 if ((sess == NULL) ||
1069 (s->enc_write_ctx == NULL) || (EVP_MD_CTX_md(s->write_hash) == NULL))
1075 mac_size = EVP_MD_CTX_size(s->write_hash);
1080 p = SSL3_BUFFER_get_buf(wb) + prefix_len;
1082 /* write the header */
1084 *(p++) = type & 0xff;
1085 SSL3_RECORD_set_type(wr, type);
1087 * Special case: for hello verify request, client version 1.0 and we
1088 * haven't decided which version to use yet send back using version 1.0
1089 * header: otherwise some clients will ignore it.
1091 if (s->method->version == DTLS_ANY_VERSION) {
1092 *(p++) = DTLS1_VERSION >> 8;
1093 *(p++) = DTLS1_VERSION & 0xff;
1095 *(p++) = s->version >> 8;
1096 *(p++) = s->version & 0xff;
1099 /* field where we are to write out packet epoch, seq num and len */
1103 /* Explicit IV length, block ciphers appropriate version flag */
1104 if (s->enc_write_ctx) {
1105 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
1106 if (mode == EVP_CIPH_CBC_MODE) {
1107 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
1111 /* Need explicit part of IV for GCM mode */
1112 else if (mode == EVP_CIPH_GCM_MODE)
1113 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
1114 else if (mode == EVP_CIPH_CCM_MODE)
1115 eivlen = EVP_CCM_TLS_EXPLICIT_IV_LEN;
1121 /* lets setup the record stuff. */
1122 SSL3_RECORD_set_data(wr, p + eivlen); /* make room for IV in case of CBC */
1123 SSL3_RECORD_set_length(wr, (int)len);
1124 SSL3_RECORD_set_input(wr, (unsigned char *)buf);
1127 * we now 'read' from wr->input, wr->length bytes into wr->data
1130 /* first we compress */
1131 if (s->compress != NULL) {
1132 if (!ssl3_do_compress(s)) {
1133 SSLerr(SSL_F_DO_DTLS1_WRITE, SSL_R_COMPRESSION_FAILURE);
1137 memcpy(SSL3_RECORD_get_data(wr), SSL3_RECORD_get_input(wr),
1138 SSL3_RECORD_get_length(wr));
1139 SSL3_RECORD_reset_input(wr);
1143 * we should still have the output to wr->data and the input from
1144 * wr->input. Length should be wr->length. wr->data still points in the
1148 if (mac_size != 0) {
1149 if (s->method->ssl3_enc->mac(s,
1150 &(p[SSL3_RECORD_get_length(wr) + eivlen]), 1) < 0)
1152 SSL3_RECORD_add_length(wr, mac_size);
1155 /* this is true regardless of mac size */
1156 SSL3_RECORD_set_data(wr, p);
1157 SSL3_RECORD_reset_input(wr);
1160 SSL3_RECORD_add_length(wr, eivlen);
1162 if (s->method->ssl3_enc->enc(s, 1) < 1)
1165 /* record length after mac and block padding */
1167 * if (type == SSL3_RT_APPLICATION_DATA || (type == SSL3_RT_ALERT && !
1171 /* there's only one epoch between handshake and app data */
1173 s2n(s->rlayer.d->w_epoch, pseq);
1177 * else s2n(s->d1->handshake_epoch, pseq);
1180 memcpy(pseq, &(s->rlayer.write_sequence[2]), 6);
1182 s2n(SSL3_RECORD_get_length(wr), pseq);
1184 if (s->msg_callback)
1185 s->msg_callback(1, 0, SSL3_RT_HEADER, pseq - DTLS1_RT_HEADER_LENGTH,
1186 DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg);
1189 * we should now have wr->data pointing to the encrypted data, which is
1192 SSL3_RECORD_set_type(wr, type); /* not needed but helps for debugging */
1193 SSL3_RECORD_add_length(wr, DTLS1_RT_HEADER_LENGTH);
1195 ssl3_record_sequence_update(&(s->rlayer.write_sequence[0]));
1197 if (create_empty_fragment) {
1199 * we are in a recursive call; just return the length, don't write
1205 /* now let's set up wb */
1206 SSL3_BUFFER_set_left(wb, prefix_len + SSL3_RECORD_get_length(wr));
1207 SSL3_BUFFER_set_offset(wb, 0);
1210 * memorize arguments so that ssl3_write_pending can detect bad write
1213 s->rlayer.wpend_tot = len;
1214 s->rlayer.wpend_buf = buf;
1215 s->rlayer.wpend_type = type;
1216 s->rlayer.wpend_ret = len;
1218 /* we now just need to write the buffer */
1219 return ssl3_write_pending(s, type, buf, len);
1224 DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr,
1225 unsigned int *is_next_epoch)
1230 /* In current epoch, accept HM, CCS, DATA, & ALERT */
1231 if (rr->epoch == s->rlayer.d->r_epoch)
1232 return &s->rlayer.d->bitmap;
1234 /* Only HM and ALERT messages can be from the next epoch */
1235 else if (rr->epoch == (unsigned long)(s->rlayer.d->r_epoch + 1) &&
1236 (rr->type == SSL3_RT_HANDSHAKE || rr->type == SSL3_RT_ALERT)) {
1238 return &s->rlayer.d->next_bitmap;
1244 void dtls1_reset_seq_numbers(SSL *s, int rw)
1247 unsigned int seq_bytes = sizeof(s->rlayer.read_sequence);
1249 if (rw & SSL3_CC_READ) {
1250 seq = s->rlayer.read_sequence;
1251 s->rlayer.d->r_epoch++;
1252 memcpy(&s->rlayer.d->bitmap, &s->rlayer.d->next_bitmap,
1253 sizeof(s->rlayer.d->bitmap));
1254 memset(&s->rlayer.d->next_bitmap, 0,
1255 sizeof(s->rlayer.d->next_bitmap));
1257 seq = s->rlayer.write_sequence;
1258 memcpy(s->rlayer.d->last_write_sequence, seq,
1259 sizeof(s->rlayer.write_sequence));
1260 s->rlayer.d->w_epoch++;
1263 memset(seq, 0, seq_bytes);