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>
69 static void get_current_time(struct timeval
*t
);
70 static void dtls1_set_handshake_header(SSL
*s
, int type
, unsigned long len
);
71 static int dtls1_handshake_write(SSL
*s
);
72 const char dtls1_version_str
[]="DTLSv1" OPENSSL_VERSION_PTEXT
;
73 int dtls1_listen(SSL
*s
, struct sockaddr
*client
);
75 const SSL3_ENC_METHOD DTLSv1_enc_data
={
79 tls1_generate_master_secret
,
80 tls1_change_cipher_state
,
81 tls1_final_finish_mac
,
82 TLS1_FINISH_MAC_LENGTH
,
84 TLS_MD_CLIENT_FINISH_CONST
,TLS_MD_CLIENT_FINISH_CONST_SIZE
,
85 TLS_MD_SERVER_FINISH_CONST
,TLS_MD_SERVER_FINISH_CONST_SIZE
,
87 tls1_export_keying_material
,
88 SSL_ENC_FLAG_DTLS
|SSL_ENC_FLAG_EXPLICIT_IV
,
89 DTLS1_HM_HEADER_LENGTH
,
90 dtls1_set_handshake_header
,
94 const SSL3_ENC_METHOD DTLSv1_2_enc_data
={
98 tls1_generate_master_secret
,
99 tls1_change_cipher_state
,
100 tls1_final_finish_mac
,
101 TLS1_FINISH_MAC_LENGTH
,
102 tls1_cert_verify_mac
,
103 TLS_MD_CLIENT_FINISH_CONST
,TLS_MD_CLIENT_FINISH_CONST_SIZE
,
104 TLS_MD_SERVER_FINISH_CONST
,TLS_MD_SERVER_FINISH_CONST_SIZE
,
106 tls1_export_keying_material
,
107 SSL_ENC_FLAG_DTLS
|SSL_ENC_FLAG_EXPLICIT_IV
|SSL_ENC_FLAG_SIGALGS
108 |SSL_ENC_FLAG_SHA256_PRF
|SSL_ENC_FLAG_TLS1_2_CIPHERS
,
109 DTLS1_HM_HEADER_LENGTH
,
110 dtls1_set_handshake_header
,
111 dtls1_handshake_write
114 long dtls1_default_timeout(void)
116 /* 2 hours, the 24 hours mentioned in the DTLSv1 spec
117 * is way too long for http, the cache would over fill */
121 int dtls1_new(SSL
*s
)
125 if (!ssl3_new(s
)) return(0);
126 if ((d1
=OPENSSL_malloc(sizeof *d1
)) == NULL
) return (0);
127 memset(d1
,0, sizeof *d1
);
129 /* d1->handshake_epoch=0; */
131 d1
->unprocessed_rcds
.q
=pqueue_new();
132 d1
->processed_rcds
.q
=pqueue_new();
133 d1
->buffered_messages
= pqueue_new();
134 d1
->sent_messages
=pqueue_new();
135 d1
->buffered_app_data
.q
=pqueue_new();
139 d1
->cookie_len
= sizeof(s
->d1
->cookie
);
142 if( ! d1
->unprocessed_rcds
.q
|| ! d1
->processed_rcds
.q
143 || ! d1
->buffered_messages
|| ! d1
->sent_messages
|| ! d1
->buffered_app_data
.q
)
145 if ( d1
->unprocessed_rcds
.q
) pqueue_free(d1
->unprocessed_rcds
.q
);
146 if ( d1
->processed_rcds
.q
) pqueue_free(d1
->processed_rcds
.q
);
147 if ( d1
->buffered_messages
) pqueue_free(d1
->buffered_messages
);
148 if ( d1
->sent_messages
) pqueue_free(d1
->sent_messages
);
149 if ( d1
->buffered_app_data
.q
) pqueue_free(d1
->buffered_app_data
.q
);
155 s
->method
->ssl_clear(s
);
159 static void dtls1_clear_queues(SSL
*s
)
162 hm_fragment
*frag
= NULL
;
163 DTLS1_RECORD_DATA
*rdata
;
165 while( (item
= pqueue_pop(s
->d1
->unprocessed_rcds
.q
)) != NULL
)
167 rdata
= (DTLS1_RECORD_DATA
*) item
->data
;
170 OPENSSL_free(rdata
->rbuf
.buf
);
172 OPENSSL_free(item
->data
);
176 while( (item
= pqueue_pop(s
->d1
->processed_rcds
.q
)) != NULL
)
178 rdata
= (DTLS1_RECORD_DATA
*) item
->data
;
181 OPENSSL_free(rdata
->rbuf
.buf
);
183 OPENSSL_free(item
->data
);
187 while( (item
= pqueue_pop(s
->d1
->buffered_messages
)) != NULL
)
189 frag
= (hm_fragment
*)item
->data
;
190 dtls1_hm_fragment_free(frag
);
194 while ( (item
= pqueue_pop(s
->d1
->sent_messages
)) != NULL
)
196 frag
= (hm_fragment
*)item
->data
;
197 dtls1_hm_fragment_free(frag
);
201 while ( (item
= pqueue_pop(s
->d1
->buffered_app_data
.q
)) != NULL
)
203 rdata
= (DTLS1_RECORD_DATA
*) item
->data
;
206 OPENSSL_free(rdata
->rbuf
.buf
);
208 OPENSSL_free(item
->data
);
213 void dtls1_free(SSL
*s
)
217 dtls1_clear_queues(s
);
219 pqueue_free(s
->d1
->unprocessed_rcds
.q
);
220 pqueue_free(s
->d1
->processed_rcds
.q
);
221 pqueue_free(s
->d1
->buffered_messages
);
222 pqueue_free(s
->d1
->sent_messages
);
223 pqueue_free(s
->d1
->buffered_app_data
.q
);
229 void dtls1_clear(SSL
*s
)
231 pqueue unprocessed_rcds
;
232 pqueue processed_rcds
;
233 pqueue buffered_messages
;
234 pqueue sent_messages
;
235 pqueue buffered_app_data
;
240 unprocessed_rcds
= s
->d1
->unprocessed_rcds
.q
;
241 processed_rcds
= s
->d1
->processed_rcds
.q
;
242 buffered_messages
= s
->d1
->buffered_messages
;
243 sent_messages
= s
->d1
->sent_messages
;
244 buffered_app_data
= s
->d1
->buffered_app_data
.q
;
247 dtls1_clear_queues(s
);
249 memset(s
->d1
, 0, sizeof(*(s
->d1
)));
253 s
->d1
->cookie_len
= sizeof(s
->d1
->cookie
);
256 if (SSL_get_options(s
) & SSL_OP_NO_QUERY_MTU
)
261 s
->d1
->unprocessed_rcds
.q
= unprocessed_rcds
;
262 s
->d1
->processed_rcds
.q
= processed_rcds
;
263 s
->d1
->buffered_messages
= buffered_messages
;
264 s
->d1
->sent_messages
= sent_messages
;
265 s
->d1
->buffered_app_data
.q
= buffered_app_data
;
269 if (s
->options
& SSL_OP_CISCO_ANYCONNECT
)
270 s
->version
=DTLS1_BAD_VER
;
271 else if (s
->method
->version
== DTLS_ANY_VERSION
)
272 s
->version
=DTLS1_2_VERSION
;
274 s
->version
=s
->method
->version
;
277 long dtls1_ctrl(SSL
*s
, int cmd
, long larg
, void *parg
)
283 case DTLS_CTRL_GET_TIMEOUT
:
284 if (dtls1_get_timeout(s
, (struct timeval
*) parg
) != NULL
)
289 case DTLS_CTRL_HANDLE_TIMEOUT
:
290 ret
= dtls1_handle_timeout(s
);
292 case DTLS_CTRL_LISTEN
:
293 ret
= dtls1_listen(s
, parg
);
295 case SSL_CTRL_CHECK_PROTO_VERSION
:
296 /* For library-internal use; checks that the current protocol
297 * is the highest enabled version (according to s->ctx->method,
298 * as version negotiation may have changed s->method). */
299 if (s
->version
== s
->ctx
->method
->version
)
301 /* Apparently we're using a version-flexible SSL_METHOD
302 * (not at its highest protocol version). */
303 if (s
->ctx
->method
->version
== DTLS_method()->version
)
305 #if DTLS_MAX_VERSION != DTLS1_2_VERSION
306 # error Code needs update for DTLS_method() support beyond DTLS1_2_VERSION.
308 if (!(s
->options
& SSL_OP_NO_DTLSv1_2
))
309 return s
->version
== DTLS1_2_VERSION
;
310 if (!(s
->options
& SSL_OP_NO_DTLSv1
))
311 return s
->version
== DTLS1_VERSION
;
313 return 0; /* Unexpected state; fail closed. */
316 ret
= ssl3_ctrl(s
, cmd
, larg
, parg
);
323 * As it's impossible to use stream ciphers in "datagram" mode, this
324 * simple filter is designed to disengage them in DTLS. Unfortunately
325 * there is no universal way to identify stream SSL_CIPHER, so we have
326 * to explicitly list their SSL_* codes. Currently RC4 is the only one
327 * available, but if new ones emerge, they will have to be added...
329 const SSL_CIPHER
*dtls1_get_cipher(unsigned int u
)
331 const SSL_CIPHER
*ciph
= ssl3_get_cipher(u
);
335 if (ciph
->algorithm_enc
== SSL_RC4
)
342 void dtls1_start_timer(SSL
*s
)
344 #ifndef OPENSSL_NO_SCTP
345 /* Disable timer for SCTP */
346 if (BIO_dgram_is_sctp(SSL_get_wbio(s
)))
348 memset(&(s
->d1
->next_timeout
), 0, sizeof(struct timeval
));
353 /* If timer is not set, initialize duration with 1 second */
354 if (s
->d1
->next_timeout
.tv_sec
== 0 && s
->d1
->next_timeout
.tv_usec
== 0)
356 s
->d1
->timeout_duration
= 1;
359 /* Set timeout to current time */
360 get_current_time(&(s
->d1
->next_timeout
));
362 /* Add duration to current time */
363 s
->d1
->next_timeout
.tv_sec
+= s
->d1
->timeout_duration
;
364 BIO_ctrl(SSL_get_rbio(s
), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT
, 0, &(s
->d1
->next_timeout
));
367 struct timeval
* dtls1_get_timeout(SSL
*s
, struct timeval
* timeleft
)
369 struct timeval timenow
;
371 /* If no timeout is set, just return NULL */
372 if (s
->d1
->next_timeout
.tv_sec
== 0 && s
->d1
->next_timeout
.tv_usec
== 0)
377 /* Get current time */
378 get_current_time(&timenow
);
380 /* If timer already expired, set remaining time to 0 */
381 if (s
->d1
->next_timeout
.tv_sec
< timenow
.tv_sec
||
382 (s
->d1
->next_timeout
.tv_sec
== timenow
.tv_sec
&&
383 s
->d1
->next_timeout
.tv_usec
<= timenow
.tv_usec
))
385 memset(timeleft
, 0, sizeof(struct timeval
));
389 /* Calculate time left until timer expires */
390 memcpy(timeleft
, &(s
->d1
->next_timeout
), sizeof(struct timeval
));
391 timeleft
->tv_sec
-= timenow
.tv_sec
;
392 timeleft
->tv_usec
-= timenow
.tv_usec
;
393 if (timeleft
->tv_usec
< 0)
396 timeleft
->tv_usec
+= 1000000;
399 /* If remaining time is less than 15 ms, set it to 0
400 * to prevent issues because of small devergences with
403 if (timeleft
->tv_sec
== 0 && timeleft
->tv_usec
< 15000)
405 memset(timeleft
, 0, sizeof(struct timeval
));
412 int dtls1_is_timer_expired(SSL
*s
)
414 struct timeval timeleft
;
416 /* Get time left until timeout, return false if no timer running */
417 if (dtls1_get_timeout(s
, &timeleft
) == NULL
)
422 /* Return false if timer is not expired yet */
423 if (timeleft
.tv_sec
> 0 || timeleft
.tv_usec
> 0)
428 /* Timer expired, so return true */
432 void dtls1_double_timeout(SSL
*s
)
434 s
->d1
->timeout_duration
*= 2;
435 if (s
->d1
->timeout_duration
> 60)
436 s
->d1
->timeout_duration
= 60;
437 dtls1_start_timer(s
);
440 void dtls1_stop_timer(SSL
*s
)
442 /* Reset everything */
443 memset(&(s
->d1
->timeout
), 0, sizeof(struct dtls1_timeout_st
));
444 memset(&(s
->d1
->next_timeout
), 0, sizeof(struct timeval
));
445 s
->d1
->timeout_duration
= 1;
446 BIO_ctrl(SSL_get_rbio(s
), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT
, 0, &(s
->d1
->next_timeout
));
447 /* Clear retransmission buffer */
448 dtls1_clear_record_buffer(s
);
451 int dtls1_check_timeout_num(SSL
*s
)
453 s
->d1
->timeout
.num_alerts
++;
455 /* Reduce MTU after 2 unsuccessful retransmissions */
456 if (s
->d1
->timeout
.num_alerts
> 2)
458 s
->d1
->mtu
= BIO_ctrl(SSL_get_wbio(s
), BIO_CTRL_DGRAM_GET_FALLBACK_MTU
, 0, NULL
);
461 if (s
->d1
->timeout
.num_alerts
> DTLS1_TMO_ALERT_COUNT
)
463 /* fail the connection, enough alerts have been sent */
464 SSLerr(SSL_F_DTLS1_CHECK_TIMEOUT_NUM
,SSL_R_READ_TIMEOUT_EXPIRED
);
471 int dtls1_handle_timeout(SSL
*s
)
473 /* if no timer is expired, don't do anything */
474 if (!dtls1_is_timer_expired(s
))
479 dtls1_double_timeout(s
);
481 if (dtls1_check_timeout_num(s
) < 0)
484 s
->d1
->timeout
.read_timeouts
++;
485 if (s
->d1
->timeout
.read_timeouts
> DTLS1_TMO_READ_COUNT
)
487 s
->d1
->timeout
.read_timeouts
= 1;
490 #ifndef OPENSSL_NO_HEARTBEATS
491 if (s
->tlsext_hb_pending
)
493 s
->tlsext_hb_pending
= 0;
494 return dtls1_heartbeat(s
);
498 dtls1_start_timer(s
);
499 return dtls1_retransmit_buffered_messages(s
);
502 static void get_current_time(struct timeval
*t
)
506 union { unsigned __int64 ul
; FILETIME ft
; } now
;
509 SystemTimeToFileTime(&st
,&now
.ft
);
511 now
.ul
-= 116444736000000000ULL;
513 now
.ul
-= 116444736000000000UI
64; /* re-bias to 1/1/1970 */
515 t
->tv_sec
= (long)(now
.ul
/10000000);
516 t
->tv_usec
= ((int)(now
.ul
%10000000))/10;
517 #elif defined(OPENSSL_SYS_VMS)
520 t
->tv_sec
= (long)tb
.time
;
521 t
->tv_usec
= (long)tb
.millitm
* 1000;
523 gettimeofday(t
, NULL
);
527 int dtls1_listen(SSL
*s
, struct sockaddr
*client
)
531 SSL_set_options(s
, SSL_OP_COOKIE_EXCHANGE
);
535 if (ret
<= 0) return ret
;
537 (void) BIO_dgram_get_peer(SSL_get_rbio(s
), client
);
541 static void dtls1_set_handshake_header(SSL
*s
, int htype
, unsigned long len
)
543 unsigned char *p
= (unsigned char *)s
->init_buf
->data
;
544 dtls1_set_message_header(s
, p
, htype
, len
, 0, len
);
545 s
->init_num
= (int)len
+ DTLS1_HM_HEADER_LENGTH
;
547 /* Buffer the message to handle re-xmits */
548 dtls1_buffer_message(s
, 0);
551 static int dtls1_handshake_write(SSL
*s
)
553 return dtls1_do_write(s
, SSL3_RT_HANDSHAKE
);