2 * Copyright 2005-2016 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
12 #include <openssl/objects.h>
13 #include <openssl/rand.h>
16 #if defined(OPENSSL_SYS_VMS)
17 # include <sys/timeb.h>
18 #elif defined(OPENSSL_SYS_VXWORKS)
19 # include <sys/times.h>
20 #elif !defined(OPENSSL_SYS_WIN32)
21 # include <sys/time.h>
24 static void get_current_time(struct timeval *t);
25 static int dtls1_set_handshake_header(SSL *s, int type, unsigned long len);
26 static int dtls1_handshake_write(SSL *s);
27 static unsigned int dtls1_link_min_mtu(void);
29 /* XDTLS: figure out the right values */
30 static const unsigned int g_probable_mtu[] = { 1500, 512, 256 };
32 const SSL3_ENC_METHOD DTLSv1_enc_data = {
36 tls1_generate_master_secret,
37 tls1_change_cipher_state,
38 tls1_final_finish_mac,
39 TLS1_FINISH_MAC_LENGTH,
40 TLS_MD_CLIENT_FINISH_CONST, TLS_MD_CLIENT_FINISH_CONST_SIZE,
41 TLS_MD_SERVER_FINISH_CONST, TLS_MD_SERVER_FINISH_CONST_SIZE,
43 tls1_export_keying_material,
44 SSL_ENC_FLAG_DTLS | SSL_ENC_FLAG_EXPLICIT_IV,
45 DTLS1_HM_HEADER_LENGTH,
46 dtls1_set_handshake_header,
50 const SSL3_ENC_METHOD DTLSv1_2_enc_data = {
54 tls1_generate_master_secret,
55 tls1_change_cipher_state,
56 tls1_final_finish_mac,
57 TLS1_FINISH_MAC_LENGTH,
58 TLS_MD_CLIENT_FINISH_CONST, TLS_MD_CLIENT_FINISH_CONST_SIZE,
59 TLS_MD_SERVER_FINISH_CONST, TLS_MD_SERVER_FINISH_CONST_SIZE,
61 tls1_export_keying_material,
62 SSL_ENC_FLAG_DTLS | SSL_ENC_FLAG_EXPLICIT_IV | SSL_ENC_FLAG_SIGALGS
63 | SSL_ENC_FLAG_SHA256_PRF | SSL_ENC_FLAG_TLS1_2_CIPHERS,
64 DTLS1_HM_HEADER_LENGTH,
65 dtls1_set_handshake_header,
69 long dtls1_default_timeout(void)
72 * 2 hours, the 24 hours mentioned in the DTLSv1 spec is way too long for
73 * http, the cache would over fill
82 if (!DTLS_RECORD_LAYER_new(&s->rlayer)) {
88 if ((d1 = OPENSSL_zalloc(sizeof(*d1))) == NULL) {
93 d1->buffered_messages = pqueue_new();
94 d1->sent_messages = pqueue_new();
97 d1->cookie_len = sizeof(s->d1->cookie);
103 if (d1->buffered_messages == NULL || d1->sent_messages == NULL) {
104 pqueue_free(d1->buffered_messages);
105 pqueue_free(d1->sent_messages);
112 s->method->ssl_clear(s);
116 static void dtls1_clear_queues(SSL *s)
118 dtls1_clear_received_buffer(s);
119 dtls1_clear_sent_buffer(s);
122 void dtls1_clear_received_buffer(SSL *s)
125 hm_fragment *frag = NULL;
127 while ((item = pqueue_pop(s->d1->buffered_messages)) != NULL) {
128 frag = (hm_fragment *)item->data;
129 dtls1_hm_fragment_free(frag);
134 void dtls1_clear_sent_buffer(SSL *s)
137 hm_fragment *frag = NULL;
139 while ((item = pqueue_pop(s->d1->sent_messages)) != NULL) {
140 frag = (hm_fragment *)item->data;
141 dtls1_hm_fragment_free(frag);
147 void dtls1_free(SSL *s)
149 DTLS_RECORD_LAYER_free(&s->rlayer);
153 dtls1_clear_queues(s);
155 pqueue_free(s->d1->buffered_messages);
156 pqueue_free(s->d1->sent_messages);
162 void dtls1_clear(SSL *s)
164 pqueue *buffered_messages;
165 pqueue *sent_messages;
167 unsigned int link_mtu;
169 DTLS_RECORD_LAYER_clear(&s->rlayer);
172 buffered_messages = s->d1->buffered_messages;
173 sent_messages = s->d1->sent_messages;
175 link_mtu = s->d1->link_mtu;
177 dtls1_clear_queues(s);
179 memset(s->d1, 0, sizeof(*s->d1));
182 s->d1->cookie_len = sizeof(s->d1->cookie);
185 if (SSL_get_options(s) & SSL_OP_NO_QUERY_MTU) {
187 s->d1->link_mtu = link_mtu;
190 s->d1->buffered_messages = buffered_messages;
191 s->d1->sent_messages = sent_messages;
196 if (s->method->version == DTLS_ANY_VERSION)
197 s->version = DTLS_MAX_VERSION;
198 #ifndef OPENSSL_NO_DTLS1_METHOD
199 else if (s->options & SSL_OP_CISCO_ANYCONNECT)
200 s->client_version = s->version = DTLS1_BAD_VER;
203 s->version = s->method->version;
206 long dtls1_ctrl(SSL *s, int cmd, long larg, void *parg)
211 case DTLS_CTRL_GET_TIMEOUT:
212 if (dtls1_get_timeout(s, (struct timeval *)parg) != NULL) {
216 case DTLS_CTRL_HANDLE_TIMEOUT:
217 ret = dtls1_handle_timeout(s);
219 case DTLS_CTRL_SET_LINK_MTU:
220 if (larg < (long)dtls1_link_min_mtu())
222 s->d1->link_mtu = larg;
224 case DTLS_CTRL_GET_LINK_MIN_MTU:
225 return (long)dtls1_link_min_mtu();
226 case SSL_CTRL_SET_MTU:
228 * We may not have a BIO set yet so can't call dtls1_min_mtu()
229 * We'll have to make do with dtls1_link_min_mtu() and max overhead
231 if (larg < (long)dtls1_link_min_mtu() - DTLS1_MAX_MTU_OVERHEAD)
236 ret = ssl3_ctrl(s, cmd, larg, parg);
242 void dtls1_start_timer(SSL *s)
244 #ifndef OPENSSL_NO_SCTP
245 /* Disable timer for SCTP */
246 if (BIO_dgram_is_sctp(SSL_get_wbio(s))) {
247 memset(&s->d1->next_timeout, 0, sizeof(s->d1->next_timeout));
252 /* If timer is not set, initialize duration with 1 second */
253 if (s->d1->next_timeout.tv_sec == 0 && s->d1->next_timeout.tv_usec == 0) {
254 s->d1->timeout_duration = 1;
257 /* Set timeout to current time */
258 get_current_time(&(s->d1->next_timeout));
260 /* Add duration to current time */
261 s->d1->next_timeout.tv_sec += s->d1->timeout_duration;
262 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT, 0,
263 &(s->d1->next_timeout));
266 struct timeval *dtls1_get_timeout(SSL *s, struct timeval *timeleft)
268 struct timeval timenow;
270 /* If no timeout is set, just return NULL */
271 if (s->d1->next_timeout.tv_sec == 0 && s->d1->next_timeout.tv_usec == 0) {
275 /* Get current time */
276 get_current_time(&timenow);
278 /* If timer already expired, set remaining time to 0 */
279 if (s->d1->next_timeout.tv_sec < timenow.tv_sec ||
280 (s->d1->next_timeout.tv_sec == timenow.tv_sec &&
281 s->d1->next_timeout.tv_usec <= timenow.tv_usec)) {
282 memset(timeleft, 0, sizeof(*timeleft));
286 /* Calculate time left until timer expires */
287 memcpy(timeleft, &(s->d1->next_timeout), sizeof(struct timeval));
288 timeleft->tv_sec -= timenow.tv_sec;
289 timeleft->tv_usec -= timenow.tv_usec;
290 if (timeleft->tv_usec < 0) {
292 timeleft->tv_usec += 1000000;
296 * If remaining time is less than 15 ms, set it to 0 to prevent issues
297 * because of small divergences with socket timeouts.
299 if (timeleft->tv_sec == 0 && timeleft->tv_usec < 15000) {
300 memset(timeleft, 0, sizeof(*timeleft));
306 int dtls1_is_timer_expired(SSL *s)
308 struct timeval timeleft;
310 /* Get time left until timeout, return false if no timer running */
311 if (dtls1_get_timeout(s, &timeleft) == NULL) {
315 /* Return false if timer is not expired yet */
316 if (timeleft.tv_sec > 0 || timeleft.tv_usec > 0) {
320 /* Timer expired, so return true */
324 void dtls1_double_timeout(SSL *s)
326 s->d1->timeout_duration *= 2;
327 if (s->d1->timeout_duration > 60)
328 s->d1->timeout_duration = 60;
329 dtls1_start_timer(s);
332 void dtls1_stop_timer(SSL *s)
334 /* Reset everything */
335 memset(&s->d1->timeout, 0, sizeof(s->d1->timeout));
336 memset(&s->d1->next_timeout, 0, sizeof(s->d1->next_timeout));
337 s->d1->timeout_duration = 1;
338 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT, 0,
339 &(s->d1->next_timeout));
340 /* Clear retransmission buffer */
341 dtls1_clear_sent_buffer(s);
344 int dtls1_check_timeout_num(SSL *s)
348 s->d1->timeout.num_alerts++;
350 /* Reduce MTU after 2 unsuccessful retransmissions */
351 if (s->d1->timeout.num_alerts > 2
352 && !(SSL_get_options(s) & SSL_OP_NO_QUERY_MTU)) {
354 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_GET_FALLBACK_MTU, 0, NULL);
355 if (mtu < s->d1->mtu)
359 if (s->d1->timeout.num_alerts > DTLS1_TMO_ALERT_COUNT) {
360 /* fail the connection, enough alerts have been sent */
361 SSLerr(SSL_F_DTLS1_CHECK_TIMEOUT_NUM, SSL_R_READ_TIMEOUT_EXPIRED);
368 int dtls1_handle_timeout(SSL *s)
370 /* if no timer is expired, don't do anything */
371 if (!dtls1_is_timer_expired(s)) {
375 dtls1_double_timeout(s);
377 if (dtls1_check_timeout_num(s) < 0)
380 s->d1->timeout.read_timeouts++;
381 if (s->d1->timeout.read_timeouts > DTLS1_TMO_READ_COUNT) {
382 s->d1->timeout.read_timeouts = 1;
384 #ifndef OPENSSL_NO_HEARTBEATS
385 if (s->tlsext_hb_pending) {
386 s->tlsext_hb_pending = 0;
387 return dtls1_heartbeat(s);
391 dtls1_start_timer(s);
392 return dtls1_retransmit_buffered_messages(s);
395 static void get_current_time(struct timeval *t)
405 SystemTimeToFileTime(&st, &now.ft);
406 /* re-bias to 1/1/1970 */
408 now.ul -= 116444736000000000ULL;
411 now.ul -= 116444736000000000UI64;
414 t->tv_sec = (long)(now.ul / 10000000);
415 t->tv_usec = ((int)(now.ul % 10000000)) / 10;
416 #elif defined(OPENSSL_SYS_VMS)
419 t->tv_sec = (long)tb.time;
420 t->tv_usec = (long)tb.millitm * 1000;
422 gettimeofday(t, NULL);
426 #define LISTEN_SUCCESS 2
427 #define LISTEN_SEND_VERIFY_REQUEST 1
429 #ifndef OPENSSL_NO_SOCK
430 int DTLSv1_listen(SSL *s, BIO_ADDR *client)
432 int next, n, ret = 0, clearpkt = 0;
433 unsigned char cookie[DTLS1_COOKIE_LENGTH];
434 unsigned char seq[SEQ_NUM_SIZE];
435 const unsigned char *data;
436 unsigned char *p, *buf;
437 unsigned long reclen, fragoff, fraglen, msglen;
438 unsigned int rectype, versmajor, msgseq, msgtype, clientvers, cookielen;
441 BIO_ADDR *tmpclient = NULL;
442 PACKET pkt, msgpkt, msgpayload, session, cookiepkt;
444 if (s->handshake_func == NULL) {
445 /* Not properly initialized yet */
446 SSL_set_accept_state(s);
449 /* Ensure there is no state left over from a previous invocation */
455 rbio = SSL_get_rbio(s);
456 wbio = SSL_get_wbio(s);
458 if (!rbio || !wbio) {
459 SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_BIO_NOT_SET);
464 * We only peek at incoming ClientHello's until we're sure we are going to
465 * to respond with a HelloVerifyRequest. If its a ClientHello with a valid
466 * cookie then we leave it in the BIO for accept to handle.
468 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_PEEK_MODE, 1, NULL);
471 * Note: This check deliberately excludes DTLS1_BAD_VER because that version
472 * requires the MAC to be calculated *including* the first ClientHello
473 * (without the cookie). Since DTLSv1_listen is stateless that cannot be
474 * supported. DTLS1_BAD_VER must use cookies in a stateful manner (e.g. via
477 if ((s->version & 0xff00) != (DTLS1_VERSION & 0xff00)) {
478 SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_UNSUPPORTED_SSL_VERSION);
482 if (s->init_buf == NULL) {
483 if ((bufm = BUF_MEM_new()) == NULL) {
484 SSLerr(SSL_F_DTLSV1_LISTEN, ERR_R_MALLOC_FAILURE);
488 if (!BUF_MEM_grow(bufm, SSL3_RT_MAX_PLAIN_LENGTH)) {
490 SSLerr(SSL_F_DTLSV1_LISTEN, ERR_R_MALLOC_FAILURE);
495 buf = (unsigned char *)s->init_buf->data;
502 * Technically a ClientHello could be SSL3_RT_MAX_PLAIN_LENGTH
503 * + DTLS1_RT_HEADER_LENGTH bytes long. Normally init_buf does not store
504 * the record header as well, but we do here. We've set up init_buf to
505 * be the standard size for simplicity. In practice we shouldn't ever
506 * receive a ClientHello as long as this. If we do it will get dropped
507 * in the record length check below.
509 n = BIO_read(rbio, buf, SSL3_RT_MAX_PLAIN_LENGTH);
512 if (BIO_should_retry(rbio)) {
513 /* Non-blocking IO */
519 /* If we hit any problems we need to clear this packet from the BIO */
522 if (!PACKET_buf_init(&pkt, buf, n)) {
523 SSLerr(SSL_F_DTLSV1_LISTEN, ERR_R_INTERNAL_ERROR);
528 * Parse the received record. If there are any problems with it we just
529 * dump it - with no alert. RFC6347 says this "Unlike TLS, DTLS is
530 * resilient in the face of invalid records (e.g., invalid formatting,
531 * length, MAC, etc.). In general, invalid records SHOULD be silently
532 * discarded, thus preserving the association; however, an error MAY be
533 * logged for diagnostic purposes."
536 /* this packet contained a partial record, dump it */
537 if (n < DTLS1_RT_HEADER_LENGTH) {
538 SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_RECORD_TOO_SMALL);
543 s->msg_callback(0, 0, SSL3_RT_HEADER, buf,
544 DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg);
546 /* Get the record header */
547 if (!PACKET_get_1(&pkt, &rectype)
548 || !PACKET_get_1(&pkt, &versmajor)) {
549 SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_LENGTH_MISMATCH);
553 if (rectype != SSL3_RT_HANDSHAKE) {
554 SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_UNEXPECTED_MESSAGE);
559 * Check record version number. We only check that the major version is
562 if (versmajor != DTLS1_VERSION_MAJOR) {
563 SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_BAD_PROTOCOL_VERSION_NUMBER);
567 if (!PACKET_forward(&pkt, 1)
568 /* Save the sequence number: 64 bits, with top 2 bytes = epoch */
569 || !PACKET_copy_bytes(&pkt, seq, SEQ_NUM_SIZE)
570 || !PACKET_get_length_prefixed_2(&pkt, &msgpkt)) {
571 SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_LENGTH_MISMATCH);
575 * We allow data remaining at the end of the packet because there could
576 * be a second record (but we ignore it)
579 /* This is an initial ClientHello so the epoch has to be 0 */
580 if (seq[0] != 0 || seq[1] != 0) {
581 SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_UNEXPECTED_MESSAGE);
585 /* Get a pointer to the raw message for the later callback */
586 data = PACKET_data(&msgpkt);
588 /* Finished processing the record header, now process the message */
589 if (!PACKET_get_1(&msgpkt, &msgtype)
590 || !PACKET_get_net_3(&msgpkt, &msglen)
591 || !PACKET_get_net_2(&msgpkt, &msgseq)
592 || !PACKET_get_net_3(&msgpkt, &fragoff)
593 || !PACKET_get_net_3(&msgpkt, &fraglen)
594 || !PACKET_get_sub_packet(&msgpkt, &msgpayload, fraglen)
595 || PACKET_remaining(&msgpkt) != 0) {
596 SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_LENGTH_MISMATCH);
600 if (msgtype != SSL3_MT_CLIENT_HELLO) {
601 SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_UNEXPECTED_MESSAGE);
605 /* Message sequence number can only be 0 or 1 */
607 SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_INVALID_SEQUENCE_NUMBER);
612 * We don't support fragment reassembly for ClientHellos whilst
613 * listening because that would require server side state (which is
614 * against the whole point of the ClientHello/HelloVerifyRequest
615 * mechanism). Instead we only look at the first ClientHello fragment
616 * and require that the cookie must be contained within it.
618 if (fragoff != 0 || fraglen > msglen) {
619 /* Non initial ClientHello fragment (or bad fragment) */
620 SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_FRAGMENTED_CLIENT_HELLO);
625 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, data,
626 fraglen + DTLS1_HM_HEADER_LENGTH, s,
627 s->msg_callback_arg);
629 if (!PACKET_get_net_2(&msgpayload, &clientvers)) {
630 SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_LENGTH_MISMATCH);
635 * Verify client version is supported
637 if (DTLS_VERSION_LT(clientvers, (unsigned int)s->method->version) &&
638 s->method->version != DTLS_ANY_VERSION) {
639 SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_WRONG_VERSION_NUMBER);
643 if (!PACKET_forward(&msgpayload, SSL3_RANDOM_SIZE)
644 || !PACKET_get_length_prefixed_1(&msgpayload, &session)
645 || !PACKET_get_length_prefixed_1(&msgpayload, &cookiepkt)) {
647 * Could be malformed or the cookie does not fit within the initial
648 * ClientHello fragment. Either way we can't handle it.
650 SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_LENGTH_MISMATCH);
655 * Check if we have a cookie or not. If not we need to send a
656 * HelloVerifyRequest.
658 if (PACKET_remaining(&cookiepkt) == 0) {
659 next = LISTEN_SEND_VERIFY_REQUEST;
662 * We have a cookie, so lets check it.
664 if (s->ctx->app_verify_cookie_cb == NULL) {
665 SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_NO_VERIFY_COOKIE_CALLBACK);
669 if (s->ctx->app_verify_cookie_cb(s, PACKET_data(&cookiepkt),
670 PACKET_remaining(&cookiepkt)) ==
673 * We treat invalid cookies in the same was as no cookie as
676 next = LISTEN_SEND_VERIFY_REQUEST;
678 /* Cookie verification succeeded */
679 next = LISTEN_SUCCESS;
683 if (next == LISTEN_SEND_VERIFY_REQUEST) {
685 * There was no cookie in the ClientHello so we need to send a
686 * HelloVerifyRequest. If this fails we do not worry about trying
687 * to resend, we just drop it.
691 * Dump the read packet, we don't need it any more. Ignore return
694 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_PEEK_MODE, 0, NULL);
695 BIO_read(rbio, buf, SSL3_RT_MAX_PLAIN_LENGTH);
696 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_PEEK_MODE, 1, NULL);
698 /* Generate the cookie */
699 if (s->ctx->app_gen_cookie_cb == NULL ||
700 s->ctx->app_gen_cookie_cb(s, cookie, &cookielen) == 0 ||
702 SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_COOKIE_GEN_CALLBACK_FAILURE);
707 p = &buf[DTLS1_RT_HEADER_LENGTH];
708 msglen = dtls_raw_hello_verify_request(p + DTLS1_HM_HEADER_LENGTH,
711 *p++ = DTLS1_MT_HELLO_VERIFY_REQUEST;
716 /* Message sequence number is always 0 for a HelloVerifyRequest */
720 * We never fragment a HelloVerifyRequest, so fragment offset is 0
721 * and fragment length is message length
726 /* Set reclen equal to length of whole handshake message */
727 reclen = msglen + DTLS1_HM_HEADER_LENGTH;
729 /* Add the record header */
732 *(p++) = SSL3_RT_HANDSHAKE;
734 * Special case: for hello verify request, client version 1.0 and we
735 * haven't decided which version to use yet send back using version
736 * 1.0 header: otherwise some clients will ignore it.
738 if (s->method->version == DTLS_ANY_VERSION) {
739 *(p++) = DTLS1_VERSION >> 8;
740 *(p++) = DTLS1_VERSION & 0xff;
742 *(p++) = s->version >> 8;
743 *(p++) = s->version & 0xff;
747 * Record sequence number is always the same as in the received
750 memcpy(p, seq, SEQ_NUM_SIZE);
757 * Set reclen equal to length of whole record including record
760 reclen += DTLS1_RT_HEADER_LENGTH;
763 s->msg_callback(1, 0, SSL3_RT_HEADER, buf,
764 DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg);
766 if ((tmpclient = BIO_ADDR_new()) == NULL) {
767 SSLerr(SSL_F_DTLSV1_LISTEN, ERR_R_MALLOC_FAILURE);
772 * This is unnecessary if rbio and wbio are one and the same - but
773 * maybe they're not. We ignore errors here - some BIOs do not
776 if (BIO_dgram_get_peer(rbio, tmpclient) > 0) {
777 (void)BIO_dgram_set_peer(wbio, tmpclient);
779 BIO_ADDR_free(tmpclient);
782 if (BIO_write(wbio, buf, reclen) < (int)reclen) {
783 if (BIO_should_retry(wbio)) {
785 * Non-blocking IO...but we're stateless, so we're just
786 * going to drop this packet.
793 if (BIO_flush(wbio) <= 0) {
794 if (BIO_should_retry(wbio)) {
796 * Non-blocking IO...but we're stateless, so we're just
797 * going to drop this packet.
804 } while (next != LISTEN_SUCCESS);
807 * Set expected sequence numbers to continue the handshake.
809 s->d1->handshake_read_seq = 1;
810 s->d1->handshake_write_seq = 1;
811 s->d1->next_handshake_write_seq = 1;
812 DTLS_RECORD_LAYER_set_write_sequence(&s->rlayer, seq);
815 * We are doing cookie exchange, so make sure we set that option in the
818 SSL_set_options(s, SSL_OP_COOKIE_EXCHANGE);
821 * Tell the state machine that we've done the initial hello verify
824 ossl_statem_set_hello_verify_done(s);
827 * Some BIOs may not support this. If we fail we clear the client address
829 if (BIO_dgram_get_peer(rbio, client) <= 0)
830 BIO_ADDR_clear(client);
835 BIO_ADDR_free(tmpclient);
836 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_PEEK_MODE, 0, NULL);
838 /* Dump this packet. Ignore return value */
839 BIO_read(rbio, buf, SSL3_RT_MAX_PLAIN_LENGTH);
845 static int dtls1_set_handshake_header(SSL *s, int htype, unsigned long len)
847 dtls1_set_message_header(s, htype, len, 0, len);
848 s->init_num = (int)len + DTLS1_HM_HEADER_LENGTH;
850 /* Buffer the message to handle re-xmits */
852 if (!dtls1_buffer_message(s, 0))
858 static int dtls1_handshake_write(SSL *s)
860 return dtls1_do_write(s, SSL3_RT_HANDSHAKE);
863 #ifndef OPENSSL_NO_HEARTBEATS
865 # define HEARTBEAT_SIZE(payload, padding) ( \
866 1 /* heartbeat type */ + \
867 2 /* heartbeat length */ + \
868 (payload) + (padding))
870 # define HEARTBEAT_SIZE_STD(payload) HEARTBEAT_SIZE(payload, 16)
872 int dtls1_process_heartbeat(SSL *s, unsigned char *p, unsigned int length)
875 unsigned short hbtype;
876 unsigned int payload;
877 unsigned int padding = 16; /* Use minimum padding */
880 s->msg_callback(0, s->version, DTLS1_RT_HEARTBEAT,
881 p, length, s, s->msg_callback_arg);
883 /* Read type and payload length */
884 if (HEARTBEAT_SIZE_STD(0) > length)
885 return 0; /* silently discard */
886 if (length > SSL3_RT_MAX_PLAIN_LENGTH)
887 return 0; /* silently discard per RFC 6520 sec. 4 */
891 if (HEARTBEAT_SIZE_STD(payload) > length)
892 return 0; /* silently discard per RFC 6520 sec. 4 */
895 if (hbtype == TLS1_HB_REQUEST) {
896 unsigned char *buffer, *bp;
897 unsigned int write_length = HEARTBEAT_SIZE(payload, padding);
900 if (write_length > SSL3_RT_MAX_PLAIN_LENGTH)
903 /* Allocate memory for the response. */
904 buffer = OPENSSL_malloc(write_length);
909 /* Enter response type, length and copy payload */
910 *bp++ = TLS1_HB_RESPONSE;
912 memcpy(bp, pl, payload);
915 if (RAND_bytes(bp, padding) <= 0) {
916 OPENSSL_free(buffer);
920 r = dtls1_write_bytes(s, DTLS1_RT_HEARTBEAT, buffer, write_length);
922 if (r >= 0 && s->msg_callback)
923 s->msg_callback(1, s->version, DTLS1_RT_HEARTBEAT,
924 buffer, write_length, s, s->msg_callback_arg);
926 OPENSSL_free(buffer);
930 } else if (hbtype == TLS1_HB_RESPONSE) {
934 * We only send sequence numbers (2 bytes unsigned int), and 16
935 * random bytes, so we just try to read the sequence number
939 if (payload == 18 && seq == s->tlsext_hb_seq) {
942 s->tlsext_hb_pending = 0;
949 int dtls1_heartbeat(SSL *s)
951 unsigned char *buf, *p;
953 unsigned int payload = 18; /* Sequence number + random bytes */
954 unsigned int padding = 16; /* Use minimum padding */
957 /* Only send if peer supports and accepts HB requests... */
958 if (!(s->tlsext_heartbeat & SSL_DTLSEXT_HB_ENABLED) ||
959 s->tlsext_heartbeat & SSL_DTLSEXT_HB_DONT_SEND_REQUESTS) {
960 SSLerr(SSL_F_DTLS1_HEARTBEAT, SSL_R_TLS_HEARTBEAT_PEER_DOESNT_ACCEPT);
964 /* ...and there is none in flight yet... */
965 if (s->tlsext_hb_pending) {
966 SSLerr(SSL_F_DTLS1_HEARTBEAT, SSL_R_TLS_HEARTBEAT_PENDING);
970 /* ...and no handshake in progress. */
971 if (SSL_in_init(s) || ossl_statem_get_in_handshake(s)) {
972 SSLerr(SSL_F_DTLS1_HEARTBEAT, SSL_R_UNEXPECTED_MESSAGE);
977 * Create HeartBeat message, we just use a sequence number
978 * as payload to distinguish different messages and add
981 size = HEARTBEAT_SIZE(payload, padding);
982 buf = OPENSSL_malloc(size);
984 SSLerr(SSL_F_DTLS1_HEARTBEAT, ERR_R_MALLOC_FAILURE);
989 *p++ = TLS1_HB_REQUEST;
990 /* Payload length (18 bytes here) */
992 /* Sequence number */
993 s2n(s->tlsext_hb_seq, p);
994 /* 16 random bytes */
995 if (RAND_bytes(p, 16) <= 0) {
996 SSLerr(SSL_F_DTLS1_HEARTBEAT, ERR_R_INTERNAL_ERROR);
1000 /* Random padding */
1001 if (RAND_bytes(p, padding) <= 0) {
1002 SSLerr(SSL_F_DTLS1_HEARTBEAT, ERR_R_INTERNAL_ERROR);
1006 ret = dtls1_write_bytes(s, DTLS1_RT_HEARTBEAT, buf, size);
1008 if (s->msg_callback)
1009 s->msg_callback(1, s->version, DTLS1_RT_HEARTBEAT,
1010 buf, size, s, s->msg_callback_arg);
1012 dtls1_start_timer(s);
1013 s->tlsext_hb_pending = 1;
1023 int dtls1_shutdown(SSL *s)
1026 #ifndef OPENSSL_NO_SCTP
1029 wbio = SSL_get_wbio(s);
1030 if (wbio != NULL && BIO_dgram_is_sctp(wbio) &&
1031 !(s->shutdown & SSL_SENT_SHUTDOWN)) {
1032 ret = BIO_dgram_sctp_wait_for_dry(wbio);
1037 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SAVE_SHUTDOWN, 1,
1041 ret = ssl3_shutdown(s);
1042 #ifndef OPENSSL_NO_SCTP
1043 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SAVE_SHUTDOWN, 0, NULL);
1048 int dtls1_query_mtu(SSL *s)
1050 if (s->d1->link_mtu) {
1052 s->d1->link_mtu - BIO_dgram_get_mtu_overhead(SSL_get_wbio(s));
1053 s->d1->link_mtu = 0;
1056 /* AHA! Figure out the MTU, and stick to the right size */
1057 if (s->d1->mtu < dtls1_min_mtu(s)) {
1058 if (!(SSL_get_options(s) & SSL_OP_NO_QUERY_MTU)) {
1060 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_QUERY_MTU, 0, NULL);
1063 * I've seen the kernel return bogus numbers when it doesn't know
1064 * (initial write), so just make sure we have a reasonable number
1066 if (s->d1->mtu < dtls1_min_mtu(s)) {
1067 /* Set to min mtu */
1068 s->d1->mtu = dtls1_min_mtu(s);
1069 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SET_MTU,
1078 static unsigned int dtls1_link_min_mtu(void)
1080 return (g_probable_mtu[(sizeof(g_probable_mtu) /
1081 sizeof(g_probable_mtu[0])) - 1]);
1084 unsigned int dtls1_min_mtu(SSL *s)
1086 return dtls1_link_min_mtu() - BIO_dgram_get_mtu_overhead(SSL_get_wbio(s));