3 * DTLS implementation written by Nagendra Modadugu
4 * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
6 /* ====================================================================
7 * Copyright (c) 1999-2005 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).
62 #include <openssl/objects.h>
65 #if defined(OPENSSL_SYS_VMS)
66 # include <sys/timeb.h>
67 #elif defined(OPENSSL_SYS_NETWARE) && !defined(_WINSOCK2API_)
68 # include <sys/timeval.h>
69 #elif defined(OPENSSL_SYS_VXWORKS)
70 # include <sys/times.h>
71 #elif !defined(OPENSSL_SYS_WIN32)
72 # include <sys/time.h>
75 static void get_current_time(struct timeval
*t
);
76 static int dtls1_set_handshake_header(SSL
*s
, int type
, unsigned long len
);
77 static int dtls1_handshake_write(SSL
*s
);
78 int dtls1_listen(SSL
*s
, struct sockaddr
*client
);
80 const SSL3_ENC_METHOD DTLSv1_enc_data
= {
84 tls1_generate_master_secret
,
85 tls1_change_cipher_state
,
86 tls1_final_finish_mac
,
87 TLS1_FINISH_MAC_LENGTH
,
89 TLS_MD_CLIENT_FINISH_CONST
, TLS_MD_CLIENT_FINISH_CONST_SIZE
,
90 TLS_MD_SERVER_FINISH_CONST
, TLS_MD_SERVER_FINISH_CONST_SIZE
,
92 tls1_export_keying_material
,
93 SSL_ENC_FLAG_DTLS
| SSL_ENC_FLAG_EXPLICIT_IV
,
94 DTLS1_HM_HEADER_LENGTH
,
95 dtls1_set_handshake_header
,
99 const SSL3_ENC_METHOD DTLSv1_2_enc_data
= {
102 tls1_setup_key_block
,
103 tls1_generate_master_secret
,
104 tls1_change_cipher_state
,
105 tls1_final_finish_mac
,
106 TLS1_FINISH_MAC_LENGTH
,
107 tls1_cert_verify_mac
,
108 TLS_MD_CLIENT_FINISH_CONST
, TLS_MD_CLIENT_FINISH_CONST_SIZE
,
109 TLS_MD_SERVER_FINISH_CONST
, TLS_MD_SERVER_FINISH_CONST_SIZE
,
111 tls1_export_keying_material
,
112 SSL_ENC_FLAG_DTLS
| SSL_ENC_FLAG_EXPLICIT_IV
| SSL_ENC_FLAG_SIGALGS
113 | SSL_ENC_FLAG_SHA256_PRF
| SSL_ENC_FLAG_TLS1_2_CIPHERS
,
114 DTLS1_HM_HEADER_LENGTH
,
115 dtls1_set_handshake_header
,
116 dtls1_handshake_write
119 long dtls1_default_timeout(void)
122 * 2 hours, the 24 hours mentioned in the DTLSv1 spec is way too long for
123 * http, the cache would over fill
125 return (60 * 60 * 2);
128 int dtls1_new(SSL
*s
)
132 if (!DTLS_RECORD_LAYER_new(&s
->rlayer
)) {
138 if ((d1
= OPENSSL_zalloc(sizeof(*d1
))) == NULL
) {
143 d1
->buffered_messages
= pqueue_new();
144 d1
->sent_messages
= pqueue_new();
147 d1
->cookie_len
= sizeof(s
->d1
->cookie
);
153 if (!d1
->buffered_messages
|| !d1
->sent_messages
) {
154 pqueue_free(d1
->buffered_messages
);
155 pqueue_free(d1
->sent_messages
);
162 s
->method
->ssl_clear(s
);
166 static void dtls1_clear_queues(SSL
*s
)
169 hm_fragment
*frag
= NULL
;
171 while ((item
= pqueue_pop(s
->d1
->buffered_messages
)) != NULL
) {
172 frag
= (hm_fragment
*)item
->data
;
173 dtls1_hm_fragment_free(frag
);
177 while ((item
= pqueue_pop(s
->d1
->sent_messages
)) != NULL
) {
178 frag
= (hm_fragment
*)item
->data
;
179 dtls1_hm_fragment_free(frag
);
184 void dtls1_free(SSL
*s
)
186 DTLS_RECORD_LAYER_free(&s
->rlayer
);
190 dtls1_clear_queues(s
);
192 pqueue_free(s
->d1
->buffered_messages
);
193 pqueue_free(s
->d1
->sent_messages
);
199 void dtls1_clear(SSL
*s
)
201 pqueue buffered_messages
;
202 pqueue sent_messages
;
204 unsigned int link_mtu
;
206 DTLS_RECORD_LAYER_clear(&s
->rlayer
);
209 buffered_messages
= s
->d1
->buffered_messages
;
210 sent_messages
= s
->d1
->sent_messages
;
212 link_mtu
= s
->d1
->link_mtu
;
214 dtls1_clear_queues(s
);
216 memset(s
->d1
, 0, sizeof(*s
->d1
));
219 s
->d1
->cookie_len
= sizeof(s
->d1
->cookie
);
222 if (SSL_get_options(s
) & SSL_OP_NO_QUERY_MTU
) {
224 s
->d1
->link_mtu
= link_mtu
;
227 s
->d1
->buffered_messages
= buffered_messages
;
228 s
->d1
->sent_messages
= sent_messages
;
232 if (s
->options
& SSL_OP_CISCO_ANYCONNECT
)
233 s
->client_version
= s
->version
= DTLS1_BAD_VER
;
234 else if (s
->method
->version
== DTLS_ANY_VERSION
)
235 s
->version
= DTLS1_2_VERSION
;
237 s
->version
= s
->method
->version
;
240 long dtls1_ctrl(SSL
*s
, int cmd
, long larg
, void *parg
)
245 case DTLS_CTRL_GET_TIMEOUT
:
246 if (dtls1_get_timeout(s
, (struct timeval
*)parg
) != NULL
) {
250 case DTLS_CTRL_HANDLE_TIMEOUT
:
251 ret
= dtls1_handle_timeout(s
);
253 case DTLS_CTRL_LISTEN
:
254 ret
= dtls1_listen(s
, parg
);
256 case SSL_CTRL_CHECK_PROTO_VERSION
:
258 * For library-internal use; checks that the current protocol is the
259 * highest enabled version (according to s->ctx->method, as version
260 * negotiation may have changed s->method).
262 if (s
->version
== s
->ctx
->method
->version
)
265 * Apparently we're using a version-flexible SSL_METHOD (not at its
266 * highest protocol version).
268 if (s
->ctx
->method
->version
== DTLS_method()->version
) {
269 #if DTLS_MAX_VERSION != DTLS1_2_VERSION
270 # error Code needs update for DTLS_method() support beyond DTLS1_2_VERSION.
272 if (!(s
->options
& SSL_OP_NO_DTLSv1_2
))
273 return s
->version
== DTLS1_2_VERSION
;
274 if (!(s
->options
& SSL_OP_NO_DTLSv1
))
275 return s
->version
== DTLS1_VERSION
;
277 return 0; /* Unexpected state; fail closed. */
278 case DTLS_CTRL_SET_LINK_MTU
:
279 if (larg
< (long)dtls1_link_min_mtu())
281 s
->d1
->link_mtu
= larg
;
283 case DTLS_CTRL_GET_LINK_MIN_MTU
:
284 return (long)dtls1_link_min_mtu();
285 case SSL_CTRL_SET_MTU
:
287 * We may not have a BIO set yet so can't call dtls1_min_mtu()
288 * We'll have to make do with dtls1_link_min_mtu() and max overhead
290 if (larg
< (long)dtls1_link_min_mtu() - DTLS1_MAX_MTU_OVERHEAD
)
295 ret
= ssl3_ctrl(s
, cmd
, larg
, parg
);
302 * As it's impossible to use stream ciphers in "datagram" mode, this
303 * simple filter is designed to disengage them in DTLS. Unfortunately
304 * there is no universal way to identify stream SSL_CIPHER, so we have
305 * to explicitly list their SSL_* codes. Currently RC4 is the only one
306 * available, but if new ones emerge, they will have to be added...
308 const SSL_CIPHER
*dtls1_get_cipher(unsigned int u
)
310 const SSL_CIPHER
*ciph
= ssl3_get_cipher(u
);
313 if (ciph
->algorithm_enc
== SSL_RC4
)
320 void dtls1_start_timer(SSL
*s
)
322 #ifndef OPENSSL_NO_SCTP
323 /* Disable timer for SCTP */
324 if (BIO_dgram_is_sctp(SSL_get_wbio(s
))) {
325 memset(&s
->d1
->next_timeout
, 0, sizeof(s
->d1
->next_timeout
));
330 /* If timer is not set, initialize duration with 1 second */
331 if (s
->d1
->next_timeout
.tv_sec
== 0 && s
->d1
->next_timeout
.tv_usec
== 0) {
332 s
->d1
->timeout_duration
= 1;
335 /* Set timeout to current time */
336 get_current_time(&(s
->d1
->next_timeout
));
338 /* Add duration to current time */
339 s
->d1
->next_timeout
.tv_sec
+= s
->d1
->timeout_duration
;
340 BIO_ctrl(SSL_get_rbio(s
), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT
, 0,
341 &(s
->d1
->next_timeout
));
344 struct timeval
*dtls1_get_timeout(SSL
*s
, struct timeval
*timeleft
)
346 struct timeval timenow
;
348 /* If no timeout is set, just return NULL */
349 if (s
->d1
->next_timeout
.tv_sec
== 0 && s
->d1
->next_timeout
.tv_usec
== 0) {
353 /* Get current time */
354 get_current_time(&timenow
);
356 /* If timer already expired, set remaining time to 0 */
357 if (s
->d1
->next_timeout
.tv_sec
< timenow
.tv_sec
||
358 (s
->d1
->next_timeout
.tv_sec
== timenow
.tv_sec
&&
359 s
->d1
->next_timeout
.tv_usec
<= timenow
.tv_usec
)) {
360 memset(timeleft
, 0, sizeof(*timeleft
));
364 /* Calculate time left until timer expires */
365 memcpy(timeleft
, &(s
->d1
->next_timeout
), sizeof(struct timeval
));
366 timeleft
->tv_sec
-= timenow
.tv_sec
;
367 timeleft
->tv_usec
-= timenow
.tv_usec
;
368 if (timeleft
->tv_usec
< 0) {
370 timeleft
->tv_usec
+= 1000000;
374 * If remaining time is less than 15 ms, set it to 0 to prevent issues
375 * because of small devergences with socket timeouts.
377 if (timeleft
->tv_sec
== 0 && timeleft
->tv_usec
< 15000) {
378 memset(timeleft
, 0, sizeof(*timeleft
));
384 int dtls1_is_timer_expired(SSL
*s
)
386 struct timeval timeleft
;
388 /* Get time left until timeout, return false if no timer running */
389 if (dtls1_get_timeout(s
, &timeleft
) == NULL
) {
393 /* Return false if timer is not expired yet */
394 if (timeleft
.tv_sec
> 0 || timeleft
.tv_usec
> 0) {
398 /* Timer expired, so return true */
402 void dtls1_double_timeout(SSL
*s
)
404 s
->d1
->timeout_duration
*= 2;
405 if (s
->d1
->timeout_duration
> 60)
406 s
->d1
->timeout_duration
= 60;
407 dtls1_start_timer(s
);
410 void dtls1_stop_timer(SSL
*s
)
412 /* Reset everything */
413 memset(&s
->d1
->timeout
, 0, sizeof(s
->d1
->timeout
));
414 memset(&s
->d1
->next_timeout
, 0, sizeof(s
->d1
->next_timeout
));
415 s
->d1
->timeout_duration
= 1;
416 BIO_ctrl(SSL_get_rbio(s
), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT
, 0,
417 &(s
->d1
->next_timeout
));
418 /* Clear retransmission buffer */
419 dtls1_clear_record_buffer(s
);
422 int dtls1_check_timeout_num(SSL
*s
)
426 s
->d1
->timeout
.num_alerts
++;
428 /* Reduce MTU after 2 unsuccessful retransmissions */
429 if (s
->d1
->timeout
.num_alerts
> 2
430 && !(SSL_get_options(s
) & SSL_OP_NO_QUERY_MTU
)) {
432 BIO_ctrl(SSL_get_wbio(s
), BIO_CTRL_DGRAM_GET_FALLBACK_MTU
, 0,
434 if (mtu
< s
->d1
->mtu
)
438 if (s
->d1
->timeout
.num_alerts
> DTLS1_TMO_ALERT_COUNT
) {
439 /* fail the connection, enough alerts have been sent */
440 SSLerr(SSL_F_DTLS1_CHECK_TIMEOUT_NUM
, SSL_R_READ_TIMEOUT_EXPIRED
);
447 int dtls1_handle_timeout(SSL
*s
)
449 /* if no timer is expired, don't do anything */
450 if (!dtls1_is_timer_expired(s
)) {
454 dtls1_double_timeout(s
);
456 if (dtls1_check_timeout_num(s
) < 0)
459 s
->d1
->timeout
.read_timeouts
++;
460 if (s
->d1
->timeout
.read_timeouts
> DTLS1_TMO_READ_COUNT
) {
461 s
->d1
->timeout
.read_timeouts
= 1;
463 #ifndef OPENSSL_NO_HEARTBEATS
464 if (s
->tlsext_hb_pending
) {
465 s
->tlsext_hb_pending
= 0;
466 return dtls1_heartbeat(s
);
470 dtls1_start_timer(s
);
471 return dtls1_retransmit_buffered_messages(s
);
474 static void get_current_time(struct timeval
*t
)
484 SystemTimeToFileTime(&st
, &now
.ft
);
486 now
.ul
-= 116444736000000000ULL;
488 now
.ul
-= 116444736000000000UI
64; /* re-bias to 1/1/1970 */
490 t
->tv_sec
= (long)(now
.ul
/ 10000000);
491 t
->tv_usec
= ((int)(now
.ul
% 10000000)) / 10;
492 #elif defined(OPENSSL_SYS_VMS)
495 t
->tv_sec
= (long)tb
.time
;
496 t
->tv_usec
= (long)tb
.millitm
* 1000;
498 gettimeofday(t
, NULL
);
503 #define LISTEN_SUCCESS 2
504 #define LISTEN_SEND_VERIFY_REQUEST 1
507 int dtls1_listen(SSL
*s
, struct sockaddr
*client
)
509 int next
, n
, ret
= 0, clearpkt
= 0;
510 unsigned char cookie
[DTLS1_COOKIE_LENGTH
];
511 unsigned char seq
[SEQ_NUM_SIZE
];
512 unsigned char *data
, *p
, *buf
;
513 unsigned long reclen
, fragoff
, fraglen
, msglen
;
514 unsigned int rectype
, versmajor
, msgseq
, msgtype
, clientvers
, cookielen
;
517 struct sockaddr_storage tmpclient
;
518 PACKET pkt
, msgpkt
, msgpayload
, session
, cookiepkt
;
520 /* Ensure there is no state left over from a previous invocation */
526 rbio
= SSL_get_rbio(s
);
527 wbio
= SSL_get_wbio(s
);
530 SSLerr(SSL_F_DTLS1_LISTEN
, SSL_R_BIO_NOT_SET
);
535 * We only peek at incoming ClientHello's until we're sure we are going to
536 * to respond with a HelloVerifyRequest. If its a ClientHello with a valid
537 * cookie then we leave it in the BIO for dtls1_accept to handle.
539 BIO_ctrl(SSL_get_rbio(s
), BIO_CTRL_DGRAM_SET_PEEK_MODE
, 1, NULL
);
542 * Note: This check deliberately excludes DTLS1_BAD_VER because that version
543 * requires the MAC to be calculated *including* the first ClientHello
544 * (without the cookie). Since DTLSv1_listen is stateless that cannot be
545 * supported. DTLS1_BAD_VER must use cookies in a stateful manner (e.g. via
548 if ((s
->version
& 0xff00) != (DTLS1_VERSION
& 0xff00)) {
549 SSLerr(SSL_F_DTLS1_LISTEN
, SSL_R_UNSUPPORTED_SSL_VERSION
);
553 if (s
->init_buf
== NULL
) {
554 if ((bufm
= BUF_MEM_new()) == NULL
) {
555 SSLerr(SSL_F_DTLS1_LISTEN
, ERR_R_MALLOC_FAILURE
);
559 if (!BUF_MEM_grow(bufm
, SSL3_RT_MAX_PLAIN_LENGTH
)) {
561 SSLerr(SSL_F_DTLS1_LISTEN
, ERR_R_MALLOC_FAILURE
);
566 buf
= (unsigned char *)s
->init_buf
->data
;
573 * Technically a ClientHello could be SSL3_RT_MAX_PLAIN_LENGTH
574 * + DTLS1_RT_HEADER_LENGTH bytes long. Normally init_buf does not store
575 * the record header as well, but we do here. We've set up init_buf to
576 * be the standard size for simplicity. In practice we shouldn't ever
577 * receive a ClientHello as long as this. If we do it will get dropped
578 * in the record length check below.
580 n
= BIO_read(rbio
, buf
, SSL3_RT_MAX_PLAIN_LENGTH
);
583 if(BIO_should_retry(rbio
)) {
584 /* Non-blocking IO */
590 /* If we hit any problems we need to clear this packet from the BIO */
593 if (!PACKET_buf_init(&pkt
, buf
, n
)) {
594 SSLerr(SSL_F_DTLS1_LISTEN
, ERR_R_INTERNAL_ERROR
);
599 * Parse the received record. If there are any problems with it we just
600 * dump it - with no alert. RFC6347 says this "Unlike TLS, DTLS is
601 * resilient in the face of invalid records (e.g., invalid formatting,
602 * length, MAC, etc.). In general, invalid records SHOULD be silently
603 * discarded, thus preserving the association; however, an error MAY be
604 * logged for diagnostic purposes."
607 /* this packet contained a partial record, dump it */
608 if (n
< DTLS1_RT_HEADER_LENGTH
) {
609 SSLerr(SSL_F_DTLS1_LISTEN
, SSL_R_RECORD_TOO_SMALL
);
614 s
->msg_callback(0, 0, SSL3_RT_HEADER
, buf
,
615 DTLS1_RT_HEADER_LENGTH
, s
, s
->msg_callback_arg
);
617 /* Get the record header */
618 if (!PACKET_get_1(&pkt
, &rectype
)
619 || !PACKET_get_1(&pkt
, &versmajor
)) {
620 SSLerr(SSL_F_DTLS1_LISTEN
, SSL_R_LENGTH_MISMATCH
);
624 if (rectype
!= SSL3_RT_HANDSHAKE
) {
625 SSLerr(SSL_F_DTLS1_LISTEN
, SSL_R_UNEXPECTED_MESSAGE
);
630 * Check record version number. We only check that the major version is
633 if (versmajor
!= DTLS1_VERSION_MAJOR
) {
634 SSLerr(SSL_F_DTLS1_LISTEN
, SSL_R_BAD_PROTOCOL_VERSION_NUMBER
);
638 if (!PACKET_forward(&pkt
, 1)
639 /* Save the sequence number: 64 bits, with top 2 bytes = epoch */
640 || !PACKET_copy_bytes(&pkt
, seq
, SEQ_NUM_SIZE
)
641 || !PACKET_get_length_prefixed_2(&pkt
, &msgpkt
)
642 || PACKET_remaining(&pkt
) != 0) {
643 SSLerr(SSL_F_DTLS1_LISTEN
, SSL_R_LENGTH_MISMATCH
);
647 /* This is an initial ClientHello so the epoch has to be 0 */
648 if (seq
[0] != 0 || seq
[1] != 0) {
649 SSLerr(SSL_F_DTLS1_LISTEN
, SSL_R_UNEXPECTED_MESSAGE
);
653 /* Get a pointer to the raw message for the later callback */
654 data
= PACKET_data(&msgpkt
);
656 /* Finished processing the record header, now process the message */
657 if (!PACKET_get_1(&msgpkt
, &msgtype
)
658 || !PACKET_get_net_3(&msgpkt
, &msglen
)
659 || !PACKET_get_net_2(&msgpkt
, &msgseq
)
660 || !PACKET_get_net_3(&msgpkt
, &fragoff
)
661 || !PACKET_get_net_3(&msgpkt
, &fraglen
)
662 || !PACKET_get_sub_packet(&msgpkt
, &msgpayload
, msglen
)
663 || PACKET_remaining(&msgpkt
) != 0) {
664 SSLerr(SSL_F_DTLS1_LISTEN
, SSL_R_LENGTH_MISMATCH
);
668 if (msgtype
!= SSL3_MT_CLIENT_HELLO
) {
669 SSLerr(SSL_F_DTLS1_LISTEN
, SSL_R_UNEXPECTED_MESSAGE
);
673 /* Message sequence number can only be 0 or 1 */
675 SSLerr(SSL_F_DTLS1_LISTEN
, SSL_R_INVALID_SEQUENCE_NUMBER
);
679 /* We don't support a fragmented ClientHello whilst listening */
680 if (fragoff
!= 0 || fraglen
!= msglen
) {
681 SSLerr(SSL_F_DTLS1_LISTEN
, SSL_R_FRAGMENTED_CLIENT_HELLO
);
686 s
->msg_callback(0, s
->version
, SSL3_RT_HANDSHAKE
, data
,
687 msglen
+ DTLS1_HM_HEADER_LENGTH
, s
,
688 s
->msg_callback_arg
);
690 if (!PACKET_get_net_2(&msgpayload
, &clientvers
)) {
691 SSLerr(SSL_F_DTLS1_LISTEN
, SSL_R_LENGTH_MISMATCH
);
696 * Verify client version is supported
698 if ((clientvers
> (unsigned int)s
->method
->version
&&
699 s
->method
->version
!= DTLS_ANY_VERSION
)) {
700 SSLerr(SSL_F_DTLS1_LISTEN
, SSL_R_WRONG_VERSION_NUMBER
);
704 if (!PACKET_forward(&msgpayload
, SSL3_RANDOM_SIZE
)
705 || !PACKET_get_length_prefixed_1(&msgpayload
, &session
)
706 || !PACKET_get_length_prefixed_1(&msgpayload
, &cookiepkt
)) {
707 SSLerr(SSL_F_DTLS1_LISTEN
, SSL_R_LENGTH_MISMATCH
);
712 * Check if we have a cookie or not. If not we need to send a
713 * HelloVerifyRequest.
715 if (PACKET_remaining(&cookiepkt
) == 0) {
716 next
= LISTEN_SEND_VERIFY_REQUEST
;
719 * We have a cookie, so lets check it.
721 if (s
->ctx
->app_verify_cookie_cb
== NULL
) {
722 SSLerr(SSL_F_DTLS1_LISTEN
, SSL_R_NO_VERIFY_COOKIE_CALLBACK
);
726 if (s
->ctx
->app_verify_cookie_cb(s
, PACKET_data(&cookiepkt
),
727 PACKET_remaining(&cookiepkt
)) ==
730 * We treat invalid cookies in the same was as no cookie as
733 next
= LISTEN_SEND_VERIFY_REQUEST
;
735 /* Cookie verification succeeded */
736 next
= LISTEN_SUCCESS
;
740 if (next
== LISTEN_SEND_VERIFY_REQUEST
) {
742 * There was no cookie in the ClientHello so we need to send a
743 * HelloVerifyRequest. If this fails we do not worry about trying
744 * to resend, we just drop it.
748 * Dump the read packet, we don't need it any more. Ignore return
751 BIO_ctrl(SSL_get_rbio(s
), BIO_CTRL_DGRAM_SET_PEEK_MODE
, 0, NULL
);
752 BIO_read(rbio
, buf
, SSL3_RT_MAX_PLAIN_LENGTH
);
753 BIO_ctrl(SSL_get_rbio(s
), BIO_CTRL_DGRAM_SET_PEEK_MODE
, 1, NULL
);
755 /* Generate the cookie */
756 if (s
->ctx
->app_gen_cookie_cb
== NULL
||
757 s
->ctx
->app_gen_cookie_cb(s
, cookie
, &cookielen
) == 0 ||
759 SSLerr(SSL_F_DTLS1_LISTEN
, SSL_R_COOKIE_GEN_CALLBACK_FAILURE
);
764 p
= &buf
[DTLS1_RT_HEADER_LENGTH
];
765 msglen
= dtls1_raw_hello_verify_request(p
+ DTLS1_HM_HEADER_LENGTH
,
768 *p
++ = DTLS1_MT_HELLO_VERIFY_REQUEST
;
773 /* Message sequence number is always 0 for a HelloVerifyRequest */
777 * We never fragment a HelloVerifyRequest, so fragment offset is 0
778 * and fragment length is message length
783 /* Set reclen equal to length of whole handshake message */
784 reclen
= msglen
+ DTLS1_HM_HEADER_LENGTH
;
786 /* Add the record header */
789 *(p
++) = SSL3_RT_HANDSHAKE
;
791 * Special case: for hello verify request, client version 1.0 and we
792 * haven't decided which version to use yet send back using version
793 * 1.0 header: otherwise some clients will ignore it.
795 if (s
->method
->version
== DTLS_ANY_VERSION
) {
796 *(p
++) = DTLS1_VERSION
>> 8;
797 *(p
++) = DTLS1_VERSION
& 0xff;
799 *(p
++) = s
->version
>> 8;
800 *(p
++) = s
->version
& 0xff;
804 * Record sequence number is always the same as in the received
807 memcpy(p
, seq
, SEQ_NUM_SIZE
);
814 * Set reclen equal to length of whole record including record
817 reclen
+= DTLS1_RT_HEADER_LENGTH
;
820 s
->msg_callback(1, 0, SSL3_RT_HEADER
, buf
,
821 DTLS1_RT_HEADER_LENGTH
, s
, s
->msg_callback_arg
);
824 * This is unneccessary if rbio and wbio are one and the same - but
827 if(BIO_dgram_get_peer(rbio
, &tmpclient
) <= 0
828 || BIO_dgram_set_peer(wbio
, &tmpclient
) <= 0) {
829 SSLerr(SSL_F_DTLS1_LISTEN
, ERR_R_INTERNAL_ERROR
);
833 if (BIO_write(wbio
, buf
, reclen
) < (int)reclen
) {
834 if(BIO_should_retry(wbio
)) {
836 * Non-blocking IO...but we're stateless, so we're just
837 * going to drop this packet.
844 if (BIO_flush(wbio
) <= 0) {
845 if(BIO_should_retry(wbio
)) {
847 * Non-blocking IO...but we're stateless, so we're just
848 * going to drop this packet.
855 } while (next
!= LISTEN_SUCCESS
);
858 * Set expected sequence numbers to continue the handshake.
860 s
->d1
->handshake_read_seq
= 1;
861 s
->d1
->handshake_write_seq
= 1;
862 s
->d1
->next_handshake_write_seq
= 1;
863 DTLS_RECORD_LAYER_set_write_sequence(&s
->rlayer
, seq
);
866 * We are doing cookie exchange, so make sure we set that option in the
869 SSL_set_options(s
, SSL_OP_COOKIE_EXCHANGE
);
871 /* Put us into the "init" state so that we don't get our state cleared */
872 statem_set_in_init(s
, 1);
874 if(BIO_dgram_get_peer(rbio
, client
) <= 0) {
875 SSLerr(SSL_F_DTLS1_LISTEN
, ERR_R_INTERNAL_ERROR
);
882 BIO_ctrl(SSL_get_rbio(s
), BIO_CTRL_DGRAM_SET_PEEK_MODE
, 0, NULL
);
884 /* Dump this packet. Ignore return value */
885 BIO_read(rbio
, buf
, SSL3_RT_MAX_PLAIN_LENGTH
);
890 static int dtls1_set_handshake_header(SSL
*s
, int htype
, unsigned long len
)
892 unsigned char *p
= (unsigned char *)s
->init_buf
->data
;
893 dtls1_set_message_header(s
, p
, htype
, len
, 0, len
);
894 s
->init_num
= (int)len
+ DTLS1_HM_HEADER_LENGTH
;
896 /* Buffer the message to handle re-xmits */
898 if (!dtls1_buffer_message(s
, 0))
904 static int dtls1_handshake_write(SSL
*s
)
906 return dtls1_do_write(s
, SSL3_RT_HANDSHAKE
);