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
)
119 hm_fragment
*frag
= NULL
;
121 while ((item
= pqueue_pop(s
->d1
->buffered_messages
)) != NULL
) {
122 frag
= (hm_fragment
*)item
->data
;
123 dtls1_hm_fragment_free(frag
);
127 while ((item
= pqueue_pop(s
->d1
->sent_messages
)) != NULL
) {
128 frag
= (hm_fragment
*)item
->data
;
129 dtls1_hm_fragment_free(frag
);
134 void dtls1_free(SSL
*s
)
136 DTLS_RECORD_LAYER_free(&s
->rlayer
);
140 dtls1_clear_queues(s
);
142 pqueue_free(s
->d1
->buffered_messages
);
143 pqueue_free(s
->d1
->sent_messages
);
149 void dtls1_clear(SSL
*s
)
151 pqueue
*buffered_messages
;
152 pqueue
*sent_messages
;
154 unsigned int link_mtu
;
156 DTLS_RECORD_LAYER_clear(&s
->rlayer
);
159 buffered_messages
= s
->d1
->buffered_messages
;
160 sent_messages
= s
->d1
->sent_messages
;
162 link_mtu
= s
->d1
->link_mtu
;
164 dtls1_clear_queues(s
);
166 memset(s
->d1
, 0, sizeof(*s
->d1
));
169 s
->d1
->cookie_len
= sizeof(s
->d1
->cookie
);
172 if (SSL_get_options(s
) & SSL_OP_NO_QUERY_MTU
) {
174 s
->d1
->link_mtu
= link_mtu
;
177 s
->d1
->buffered_messages
= buffered_messages
;
178 s
->d1
->sent_messages
= sent_messages
;
182 if (s
->options
& SSL_OP_CISCO_ANYCONNECT
)
183 s
->client_version
= s
->version
= DTLS1_BAD_VER
;
184 else if (s
->method
->version
== DTLS_ANY_VERSION
)
185 s
->version
= DTLS_MAX_VERSION
;
187 s
->version
= s
->method
->version
;
190 long dtls1_ctrl(SSL
*s
, int cmd
, long larg
, void *parg
)
195 case DTLS_CTRL_GET_TIMEOUT
:
196 if (dtls1_get_timeout(s
, (struct timeval
*)parg
) != NULL
) {
200 case DTLS_CTRL_HANDLE_TIMEOUT
:
201 ret
= dtls1_handle_timeout(s
);
203 case DTLS_CTRL_SET_LINK_MTU
:
204 if (larg
< (long)dtls1_link_min_mtu())
206 s
->d1
->link_mtu
= larg
;
208 case DTLS_CTRL_GET_LINK_MIN_MTU
:
209 return (long)dtls1_link_min_mtu();
210 case SSL_CTRL_SET_MTU
:
212 * We may not have a BIO set yet so can't call dtls1_min_mtu()
213 * We'll have to make do with dtls1_link_min_mtu() and max overhead
215 if (larg
< (long)dtls1_link_min_mtu() - DTLS1_MAX_MTU_OVERHEAD
)
220 ret
= ssl3_ctrl(s
, cmd
, larg
, parg
);
226 void dtls1_start_timer(SSL
*s
)
228 #ifndef OPENSSL_NO_SCTP
229 /* Disable timer for SCTP */
230 if (BIO_dgram_is_sctp(SSL_get_wbio(s
))) {
231 memset(&s
->d1
->next_timeout
, 0, sizeof(s
->d1
->next_timeout
));
236 /* If timer is not set, initialize duration with 1 second */
237 if (s
->d1
->next_timeout
.tv_sec
== 0 && s
->d1
->next_timeout
.tv_usec
== 0) {
238 s
->d1
->timeout_duration
= 1;
241 /* Set timeout to current time */
242 get_current_time(&(s
->d1
->next_timeout
));
244 /* Add duration to current time */
245 s
->d1
->next_timeout
.tv_sec
+= s
->d1
->timeout_duration
;
246 BIO_ctrl(SSL_get_rbio(s
), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT
, 0,
247 &(s
->d1
->next_timeout
));
250 struct timeval
*dtls1_get_timeout(SSL
*s
, struct timeval
*timeleft
)
252 struct timeval timenow
;
254 /* If no timeout is set, just return NULL */
255 if (s
->d1
->next_timeout
.tv_sec
== 0 && s
->d1
->next_timeout
.tv_usec
== 0) {
259 /* Get current time */
260 get_current_time(&timenow
);
262 /* If timer already expired, set remaining time to 0 */
263 if (s
->d1
->next_timeout
.tv_sec
< timenow
.tv_sec
||
264 (s
->d1
->next_timeout
.tv_sec
== timenow
.tv_sec
&&
265 s
->d1
->next_timeout
.tv_usec
<= timenow
.tv_usec
)) {
266 memset(timeleft
, 0, sizeof(*timeleft
));
270 /* Calculate time left until timer expires */
271 memcpy(timeleft
, &(s
->d1
->next_timeout
), sizeof(struct timeval
));
272 timeleft
->tv_sec
-= timenow
.tv_sec
;
273 timeleft
->tv_usec
-= timenow
.tv_usec
;
274 if (timeleft
->tv_usec
< 0) {
276 timeleft
->tv_usec
+= 1000000;
280 * If remaining time is less than 15 ms, set it to 0 to prevent issues
281 * because of small divergences with socket timeouts.
283 if (timeleft
->tv_sec
== 0 && timeleft
->tv_usec
< 15000) {
284 memset(timeleft
, 0, sizeof(*timeleft
));
290 int dtls1_is_timer_expired(SSL
*s
)
292 struct timeval timeleft
;
294 /* Get time left until timeout, return false if no timer running */
295 if (dtls1_get_timeout(s
, &timeleft
) == NULL
) {
299 /* Return false if timer is not expired yet */
300 if (timeleft
.tv_sec
> 0 || timeleft
.tv_usec
> 0) {
304 /* Timer expired, so return true */
308 void dtls1_double_timeout(SSL
*s
)
310 s
->d1
->timeout_duration
*= 2;
311 if (s
->d1
->timeout_duration
> 60)
312 s
->d1
->timeout_duration
= 60;
313 dtls1_start_timer(s
);
316 void dtls1_stop_timer(SSL
*s
)
318 /* Reset everything */
319 memset(&s
->d1
->timeout
, 0, sizeof(s
->d1
->timeout
));
320 memset(&s
->d1
->next_timeout
, 0, sizeof(s
->d1
->next_timeout
));
321 s
->d1
->timeout_duration
= 1;
322 BIO_ctrl(SSL_get_rbio(s
), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT
, 0,
323 &(s
->d1
->next_timeout
));
324 /* Clear retransmission buffer */
325 dtls1_clear_record_buffer(s
);
328 int dtls1_check_timeout_num(SSL
*s
)
332 s
->d1
->timeout
.num_alerts
++;
334 /* Reduce MTU after 2 unsuccessful retransmissions */
335 if (s
->d1
->timeout
.num_alerts
> 2
336 && !(SSL_get_options(s
) & SSL_OP_NO_QUERY_MTU
)) {
338 BIO_ctrl(SSL_get_wbio(s
), BIO_CTRL_DGRAM_GET_FALLBACK_MTU
, 0,
340 if (mtu
< s
->d1
->mtu
)
344 if (s
->d1
->timeout
.num_alerts
> DTLS1_TMO_ALERT_COUNT
) {
345 /* fail the connection, enough alerts have been sent */
346 SSLerr(SSL_F_DTLS1_CHECK_TIMEOUT_NUM
, SSL_R_READ_TIMEOUT_EXPIRED
);
353 int dtls1_handle_timeout(SSL
*s
)
355 /* if no timer is expired, don't do anything */
356 if (!dtls1_is_timer_expired(s
)) {
360 dtls1_double_timeout(s
);
362 if (dtls1_check_timeout_num(s
) < 0)
365 s
->d1
->timeout
.read_timeouts
++;
366 if (s
->d1
->timeout
.read_timeouts
> DTLS1_TMO_READ_COUNT
) {
367 s
->d1
->timeout
.read_timeouts
= 1;
369 #ifndef OPENSSL_NO_HEARTBEATS
370 if (s
->tlsext_hb_pending
) {
371 s
->tlsext_hb_pending
= 0;
372 return dtls1_heartbeat(s
);
376 dtls1_start_timer(s
);
377 return dtls1_retransmit_buffered_messages(s
);
380 static void get_current_time(struct timeval
*t
)
390 SystemTimeToFileTime(&st
, &now
.ft
);
392 now
.ul
-= 116444736000000000ULL;
394 now
.ul
-= 116444736000000000UI
64; /* re-bias to 1/1/1970 */
396 t
->tv_sec
= (long)(now
.ul
/ 10000000);
397 t
->tv_usec
= ((int)(now
.ul
% 10000000)) / 10;
398 #elif defined(OPENSSL_SYS_VMS)
401 t
->tv_sec
= (long)tb
.time
;
402 t
->tv_usec
= (long)tb
.millitm
* 1000;
404 gettimeofday(t
, NULL
);
409 #define LISTEN_SUCCESS 2
410 #define LISTEN_SEND_VERIFY_REQUEST 1
412 #ifndef OPENSSL_NO_SOCK
413 int DTLSv1_listen(SSL
*s
, BIO_ADDR
*client
)
415 int next
, n
, ret
= 0, clearpkt
= 0;
416 unsigned char cookie
[DTLS1_COOKIE_LENGTH
];
417 unsigned char seq
[SEQ_NUM_SIZE
];
418 const unsigned char *data
;
419 unsigned char *p
, *buf
;
420 unsigned long reclen
, fragoff
, fraglen
, msglen
;
421 unsigned int rectype
, versmajor
, msgseq
, msgtype
, clientvers
, cookielen
;
424 BIO_ADDR
*tmpclient
= NULL
;
425 PACKET pkt
, msgpkt
, msgpayload
, session
, cookiepkt
;
427 /* Ensure there is no state left over from a previous invocation */
433 rbio
= SSL_get_rbio(s
);
434 wbio
= SSL_get_wbio(s
);
437 SSLerr(SSL_F_DTLSV1_LISTEN
, SSL_R_BIO_NOT_SET
);
442 * We only peek at incoming ClientHello's until we're sure we are going to
443 * to respond with a HelloVerifyRequest. If its a ClientHello with a valid
444 * cookie then we leave it in the BIO for accept to handle.
446 BIO_ctrl(SSL_get_rbio(s
), BIO_CTRL_DGRAM_SET_PEEK_MODE
, 1, NULL
);
449 * Note: This check deliberately excludes DTLS1_BAD_VER because that version
450 * requires the MAC to be calculated *including* the first ClientHello
451 * (without the cookie). Since DTLSv1_listen is stateless that cannot be
452 * supported. DTLS1_BAD_VER must use cookies in a stateful manner (e.g. via
455 if ((s
->version
& 0xff00) != (DTLS1_VERSION
& 0xff00)) {
456 SSLerr(SSL_F_DTLSV1_LISTEN
, SSL_R_UNSUPPORTED_SSL_VERSION
);
460 if (s
->init_buf
== NULL
) {
461 if ((bufm
= BUF_MEM_new()) == NULL
) {
462 SSLerr(SSL_F_DTLSV1_LISTEN
, ERR_R_MALLOC_FAILURE
);
466 if (!BUF_MEM_grow(bufm
, SSL3_RT_MAX_PLAIN_LENGTH
)) {
468 SSLerr(SSL_F_DTLSV1_LISTEN
, ERR_R_MALLOC_FAILURE
);
473 buf
= (unsigned char *)s
->init_buf
->data
;
480 * Technically a ClientHello could be SSL3_RT_MAX_PLAIN_LENGTH
481 * + DTLS1_RT_HEADER_LENGTH bytes long. Normally init_buf does not store
482 * the record header as well, but we do here. We've set up init_buf to
483 * be the standard size for simplicity. In practice we shouldn't ever
484 * receive a ClientHello as long as this. If we do it will get dropped
485 * in the record length check below.
487 n
= BIO_read(rbio
, buf
, SSL3_RT_MAX_PLAIN_LENGTH
);
490 if(BIO_should_retry(rbio
)) {
491 /* Non-blocking IO */
497 /* If we hit any problems we need to clear this packet from the BIO */
500 if (!PACKET_buf_init(&pkt
, buf
, n
)) {
501 SSLerr(SSL_F_DTLSV1_LISTEN
, ERR_R_INTERNAL_ERROR
);
506 * Parse the received record. If there are any problems with it we just
507 * dump it - with no alert. RFC6347 says this "Unlike TLS, DTLS is
508 * resilient in the face of invalid records (e.g., invalid formatting,
509 * length, MAC, etc.). In general, invalid records SHOULD be silently
510 * discarded, thus preserving the association; however, an error MAY be
511 * logged for diagnostic purposes."
514 /* this packet contained a partial record, dump it */
515 if (n
< DTLS1_RT_HEADER_LENGTH
) {
516 SSLerr(SSL_F_DTLSV1_LISTEN
, SSL_R_RECORD_TOO_SMALL
);
521 s
->msg_callback(0, 0, SSL3_RT_HEADER
, buf
,
522 DTLS1_RT_HEADER_LENGTH
, s
, s
->msg_callback_arg
);
524 /* Get the record header */
525 if (!PACKET_get_1(&pkt
, &rectype
)
526 || !PACKET_get_1(&pkt
, &versmajor
)) {
527 SSLerr(SSL_F_DTLSV1_LISTEN
, SSL_R_LENGTH_MISMATCH
);
531 if (rectype
!= SSL3_RT_HANDSHAKE
) {
532 SSLerr(SSL_F_DTLSV1_LISTEN
, SSL_R_UNEXPECTED_MESSAGE
);
537 * Check record version number. We only check that the major version is
540 if (versmajor
!= DTLS1_VERSION_MAJOR
) {
541 SSLerr(SSL_F_DTLSV1_LISTEN
, SSL_R_BAD_PROTOCOL_VERSION_NUMBER
);
545 if (!PACKET_forward(&pkt
, 1)
546 /* Save the sequence number: 64 bits, with top 2 bytes = epoch */
547 || !PACKET_copy_bytes(&pkt
, seq
, SEQ_NUM_SIZE
)
548 || !PACKET_get_length_prefixed_2(&pkt
, &msgpkt
)) {
549 SSLerr(SSL_F_DTLSV1_LISTEN
, SSL_R_LENGTH_MISMATCH
);
553 * We allow data remaining at the end of the packet because there could
554 * be a second record (but we ignore it)
557 /* This is an initial ClientHello so the epoch has to be 0 */
558 if (seq
[0] != 0 || seq
[1] != 0) {
559 SSLerr(SSL_F_DTLSV1_LISTEN
, SSL_R_UNEXPECTED_MESSAGE
);
563 /* Get a pointer to the raw message for the later callback */
564 data
= PACKET_data(&msgpkt
);
566 /* Finished processing the record header, now process the message */
567 if (!PACKET_get_1(&msgpkt
, &msgtype
)
568 || !PACKET_get_net_3(&msgpkt
, &msglen
)
569 || !PACKET_get_net_2(&msgpkt
, &msgseq
)
570 || !PACKET_get_net_3(&msgpkt
, &fragoff
)
571 || !PACKET_get_net_3(&msgpkt
, &fraglen
)
572 || !PACKET_get_sub_packet(&msgpkt
, &msgpayload
, fraglen
)
573 || PACKET_remaining(&msgpkt
) != 0) {
574 SSLerr(SSL_F_DTLSV1_LISTEN
, SSL_R_LENGTH_MISMATCH
);
578 if (msgtype
!= SSL3_MT_CLIENT_HELLO
) {
579 SSLerr(SSL_F_DTLSV1_LISTEN
, SSL_R_UNEXPECTED_MESSAGE
);
583 /* Message sequence number can only be 0 or 1 */
585 SSLerr(SSL_F_DTLSV1_LISTEN
, SSL_R_INVALID_SEQUENCE_NUMBER
);
590 * We don't support fragment reassembly for ClientHellos whilst
591 * listening because that would require server side state (which is
592 * against the whole point of the ClientHello/HelloVerifyRequest
593 * mechanism). Instead we only look at the first ClientHello fragment
594 * and require that the cookie must be contained within it.
596 if (fragoff
!= 0 || fraglen
> msglen
) {
597 /* Non initial ClientHello fragment (or bad fragment) */
598 SSLerr(SSL_F_DTLSV1_LISTEN
, SSL_R_FRAGMENTED_CLIENT_HELLO
);
603 s
->msg_callback(0, s
->version
, SSL3_RT_HANDSHAKE
, data
,
604 fraglen
+ DTLS1_HM_HEADER_LENGTH
, s
,
605 s
->msg_callback_arg
);
607 if (!PACKET_get_net_2(&msgpayload
, &clientvers
)) {
608 SSLerr(SSL_F_DTLSV1_LISTEN
, SSL_R_LENGTH_MISMATCH
);
613 * Verify client version is supported
615 if (DTLS_VERSION_LT(clientvers
, (unsigned int)s
->method
->version
) &&
616 s
->method
->version
!= DTLS_ANY_VERSION
) {
617 SSLerr(SSL_F_DTLSV1_LISTEN
, SSL_R_WRONG_VERSION_NUMBER
);
621 if (!PACKET_forward(&msgpayload
, SSL3_RANDOM_SIZE
)
622 || !PACKET_get_length_prefixed_1(&msgpayload
, &session
)
623 || !PACKET_get_length_prefixed_1(&msgpayload
, &cookiepkt
)) {
625 * Could be malformed or the cookie does not fit within the initial
626 * ClientHello fragment. Either way we can't handle it.
628 SSLerr(SSL_F_DTLSV1_LISTEN
, SSL_R_LENGTH_MISMATCH
);
633 * Check if we have a cookie or not. If not we need to send a
634 * HelloVerifyRequest.
636 if (PACKET_remaining(&cookiepkt
) == 0) {
637 next
= LISTEN_SEND_VERIFY_REQUEST
;
640 * We have a cookie, so lets check it.
642 if (s
->ctx
->app_verify_cookie_cb
== NULL
) {
643 SSLerr(SSL_F_DTLSV1_LISTEN
, SSL_R_NO_VERIFY_COOKIE_CALLBACK
);
647 if (s
->ctx
->app_verify_cookie_cb(s
, PACKET_data(&cookiepkt
),
648 PACKET_remaining(&cookiepkt
)) ==
651 * We treat invalid cookies in the same was as no cookie as
654 next
= LISTEN_SEND_VERIFY_REQUEST
;
656 /* Cookie verification succeeded */
657 next
= LISTEN_SUCCESS
;
661 if (next
== LISTEN_SEND_VERIFY_REQUEST
) {
663 * There was no cookie in the ClientHello so we need to send a
664 * HelloVerifyRequest. If this fails we do not worry about trying
665 * to resend, we just drop it.
669 * Dump the read packet, we don't need it any more. Ignore return
672 BIO_ctrl(SSL_get_rbio(s
), BIO_CTRL_DGRAM_SET_PEEK_MODE
, 0, NULL
);
673 BIO_read(rbio
, buf
, SSL3_RT_MAX_PLAIN_LENGTH
);
674 BIO_ctrl(SSL_get_rbio(s
), BIO_CTRL_DGRAM_SET_PEEK_MODE
, 1, NULL
);
676 /* Generate the cookie */
677 if (s
->ctx
->app_gen_cookie_cb
== NULL
||
678 s
->ctx
->app_gen_cookie_cb(s
, cookie
, &cookielen
) == 0 ||
680 SSLerr(SSL_F_DTLSV1_LISTEN
, SSL_R_COOKIE_GEN_CALLBACK_FAILURE
);
685 p
= &buf
[DTLS1_RT_HEADER_LENGTH
];
686 msglen
= dtls_raw_hello_verify_request(p
+ DTLS1_HM_HEADER_LENGTH
,
689 *p
++ = DTLS1_MT_HELLO_VERIFY_REQUEST
;
694 /* Message sequence number is always 0 for a HelloVerifyRequest */
698 * We never fragment a HelloVerifyRequest, so fragment offset is 0
699 * and fragment length is message length
704 /* Set reclen equal to length of whole handshake message */
705 reclen
= msglen
+ DTLS1_HM_HEADER_LENGTH
;
707 /* Add the record header */
710 *(p
++) = SSL3_RT_HANDSHAKE
;
712 * Special case: for hello verify request, client version 1.0 and we
713 * haven't decided which version to use yet send back using version
714 * 1.0 header: otherwise some clients will ignore it.
716 if (s
->method
->version
== DTLS_ANY_VERSION
) {
717 *(p
++) = DTLS1_VERSION
>> 8;
718 *(p
++) = DTLS1_VERSION
& 0xff;
720 *(p
++) = s
->version
>> 8;
721 *(p
++) = s
->version
& 0xff;
725 * Record sequence number is always the same as in the received
728 memcpy(p
, seq
, SEQ_NUM_SIZE
);
735 * Set reclen equal to length of whole record including record
738 reclen
+= DTLS1_RT_HEADER_LENGTH
;
741 s
->msg_callback(1, 0, SSL3_RT_HEADER
, buf
,
742 DTLS1_RT_HEADER_LENGTH
, s
, s
->msg_callback_arg
);
745 if ((tmpclient
= BIO_ADDR_new()) == NULL
) {
746 SSLerr(SSL_F_DTLSV1_LISTEN
, ERR_R_MALLOC_FAILURE
);
751 * This is unnecessary if rbio and wbio are one and the same - but
752 * maybe they're not. We ignore errors here - some BIOs do not
755 if(BIO_dgram_get_peer(rbio
, tmpclient
) > 0) {
756 (void)BIO_dgram_set_peer(wbio
, tmpclient
);
758 BIO_ADDR_free(tmpclient
);
761 if (BIO_write(wbio
, buf
, reclen
) < (int)reclen
) {
762 if(BIO_should_retry(wbio
)) {
764 * Non-blocking IO...but we're stateless, so we're just
765 * going to drop this packet.
772 if (BIO_flush(wbio
) <= 0) {
773 if(BIO_should_retry(wbio
)) {
775 * Non-blocking IO...but we're stateless, so we're just
776 * going to drop this packet.
783 } while (next
!= LISTEN_SUCCESS
);
786 * Set expected sequence numbers to continue the handshake.
788 s
->d1
->handshake_read_seq
= 1;
789 s
->d1
->handshake_write_seq
= 1;
790 s
->d1
->next_handshake_write_seq
= 1;
791 DTLS_RECORD_LAYER_set_write_sequence(&s
->rlayer
, seq
);
794 * We are doing cookie exchange, so make sure we set that option in the
797 SSL_set_options(s
, SSL_OP_COOKIE_EXCHANGE
);
800 * Tell the state machine that we've done the initial hello verify
803 ossl_statem_set_hello_verify_done(s
);
805 /* Some BIOs may not support this. If we fail we clear the client address */
806 if (BIO_dgram_get_peer(rbio
, client
) <= 0)
807 BIO_ADDR_clear(client
);
812 BIO_ADDR_free(tmpclient
);
813 BIO_ctrl(SSL_get_rbio(s
), BIO_CTRL_DGRAM_SET_PEEK_MODE
, 0, NULL
);
815 /* Dump this packet. Ignore return value */
816 BIO_read(rbio
, buf
, SSL3_RT_MAX_PLAIN_LENGTH
);
822 static int dtls1_set_handshake_header(SSL
*s
, int htype
, unsigned long len
)
824 dtls1_set_message_header(s
, htype
, len
, 0, len
);
825 s
->init_num
= (int)len
+ DTLS1_HM_HEADER_LENGTH
;
827 /* Buffer the message to handle re-xmits */
829 if (!dtls1_buffer_message(s
, 0))
835 static int dtls1_handshake_write(SSL
*s
)
837 return dtls1_do_write(s
, SSL3_RT_HANDSHAKE
);
840 #ifndef OPENSSL_NO_HEARTBEATS
842 #define HEARTBEAT_SIZE(payload, padding) ( \
843 1 /* heartbeat type */ + \
844 2 /* heartbeat length */ + \
845 (payload) + (padding))
847 #define HEARTBEAT_SIZE_STD(payload) HEARTBEAT_SIZE(payload, 16)
849 int dtls1_process_heartbeat(SSL
*s
, unsigned char *p
, unsigned int length
)
852 unsigned short hbtype
;
853 unsigned int payload
;
854 unsigned int padding
= 16; /* Use minimum padding */
857 s
->msg_callback(0, s
->version
, DTLS1_RT_HEARTBEAT
,
858 p
, length
, s
, s
->msg_callback_arg
);
860 /* Read type and payload length */
861 if (HEARTBEAT_SIZE_STD(0) > length
)
862 return 0; /* silently discard */
863 if (length
> SSL3_RT_MAX_PLAIN_LENGTH
)
864 return 0; /* silently discard per RFC 6520 sec. 4 */
868 if (HEARTBEAT_SIZE_STD(payload
) > length
)
869 return 0; /* silently discard per RFC 6520 sec. 4 */
872 if (hbtype
== TLS1_HB_REQUEST
) {
873 unsigned char *buffer
, *bp
;
874 unsigned int write_length
= HEARTBEAT_SIZE(payload
, padding
);
877 if (write_length
> SSL3_RT_MAX_PLAIN_LENGTH
)
880 /* Allocate memory for the response. */
881 buffer
= OPENSSL_malloc(write_length
);
886 /* Enter response type, length and copy payload */
887 *bp
++ = TLS1_HB_RESPONSE
;
889 memcpy(bp
, pl
, payload
);
892 if (RAND_bytes(bp
, padding
) <= 0) {
893 OPENSSL_free(buffer
);
897 r
= dtls1_write_bytes(s
, DTLS1_RT_HEARTBEAT
, buffer
, write_length
);
899 if (r
>= 0 && s
->msg_callback
)
900 s
->msg_callback(1, s
->version
, DTLS1_RT_HEARTBEAT
,
901 buffer
, write_length
, s
, s
->msg_callback_arg
);
903 OPENSSL_free(buffer
);
907 } else if (hbtype
== TLS1_HB_RESPONSE
) {
911 * We only send sequence numbers (2 bytes unsigned int), and 16
912 * random bytes, so we just try to read the sequence number
916 if (payload
== 18 && seq
== s
->tlsext_hb_seq
) {
919 s
->tlsext_hb_pending
= 0;
926 int dtls1_heartbeat(SSL
*s
)
928 unsigned char *buf
, *p
;
930 unsigned int payload
= 18; /* Sequence number + random bytes */
931 unsigned int padding
= 16; /* Use minimum padding */
934 /* Only send if peer supports and accepts HB requests... */
935 if (!(s
->tlsext_heartbeat
& SSL_DTLSEXT_HB_ENABLED
) ||
936 s
->tlsext_heartbeat
& SSL_DTLSEXT_HB_DONT_SEND_REQUESTS
) {
937 SSLerr(SSL_F_DTLS1_HEARTBEAT
, SSL_R_TLS_HEARTBEAT_PEER_DOESNT_ACCEPT
);
941 /* ...and there is none in flight yet... */
942 if (s
->tlsext_hb_pending
) {
943 SSLerr(SSL_F_DTLS1_HEARTBEAT
, SSL_R_TLS_HEARTBEAT_PENDING
);
947 /* ...and no handshake in progress. */
948 if (SSL_in_init(s
) || ossl_statem_get_in_handshake(s
)) {
949 SSLerr(SSL_F_DTLS1_HEARTBEAT
, SSL_R_UNEXPECTED_MESSAGE
);
954 * Create HeartBeat message, we just use a sequence number
955 * as payload to distinguish different messages and add
958 size
= HEARTBEAT_SIZE(payload
, padding
);
959 buf
= OPENSSL_malloc(size
);
961 SSLerr(SSL_F_DTLS1_HEARTBEAT
, ERR_R_MALLOC_FAILURE
);
966 *p
++ = TLS1_HB_REQUEST
;
967 /* Payload length (18 bytes here) */
969 /* Sequence number */
970 s2n(s
->tlsext_hb_seq
, p
);
971 /* 16 random bytes */
972 if (RAND_bytes(p
, 16) <= 0) {
973 SSLerr(SSL_F_DTLS1_HEARTBEAT
, ERR_R_INTERNAL_ERROR
);
978 if (RAND_bytes(p
, padding
) <= 0) {
979 SSLerr(SSL_F_DTLS1_HEARTBEAT
, ERR_R_INTERNAL_ERROR
);
983 ret
= dtls1_write_bytes(s
, DTLS1_RT_HEARTBEAT
, buf
, size
);
986 s
->msg_callback(1, s
->version
, DTLS1_RT_HEARTBEAT
,
988 s
, s
->msg_callback_arg
);
990 dtls1_start_timer(s
);
991 s
->tlsext_hb_pending
= 1;
1001 int dtls1_shutdown(SSL
*s
)
1004 #ifndef OPENSSL_NO_SCTP
1007 wbio
= SSL_get_wbio(s
);
1008 if (wbio
!= NULL
&& BIO_dgram_is_sctp(wbio
) &&
1009 !(s
->shutdown
& SSL_SENT_SHUTDOWN
)) {
1010 ret
= BIO_dgram_sctp_wait_for_dry(wbio
);
1015 BIO_ctrl(SSL_get_wbio(s
), BIO_CTRL_DGRAM_SCTP_SAVE_SHUTDOWN
, 1,
1019 ret
= ssl3_shutdown(s
);
1020 #ifndef OPENSSL_NO_SCTP
1021 BIO_ctrl(SSL_get_wbio(s
), BIO_CTRL_DGRAM_SCTP_SAVE_SHUTDOWN
, 0, NULL
);
1026 int dtls1_query_mtu(SSL
*s
)
1028 if (s
->d1
->link_mtu
) {
1030 s
->d1
->link_mtu
- BIO_dgram_get_mtu_overhead(SSL_get_wbio(s
));
1031 s
->d1
->link_mtu
= 0;
1034 /* AHA! Figure out the MTU, and stick to the right size */
1035 if (s
->d1
->mtu
< dtls1_min_mtu(s
)) {
1036 if (!(SSL_get_options(s
) & SSL_OP_NO_QUERY_MTU
)) {
1038 BIO_ctrl(SSL_get_wbio(s
), BIO_CTRL_DGRAM_QUERY_MTU
, 0, NULL
);
1041 * I've seen the kernel return bogus numbers when it doesn't know
1042 * (initial write), so just make sure we have a reasonable number
1044 if (s
->d1
->mtu
< dtls1_min_mtu(s
)) {
1045 /* Set to min mtu */
1046 s
->d1
->mtu
= dtls1_min_mtu(s
);
1047 BIO_ctrl(SSL_get_wbio(s
), BIO_CTRL_DGRAM_SET_MTU
,
1056 static unsigned int dtls1_link_min_mtu(void)
1058 return (g_probable_mtu
[(sizeof(g_probable_mtu
) /
1059 sizeof(g_probable_mtu
[0])) - 1]);
1062 unsigned int dtls1_min_mtu(SSL
*s
)
1064 return dtls1_link_min_mtu() - BIO_dgram_get_mtu_overhead(SSL_get_wbio(s
));