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_WIN32) || defined(OPENSSL_SYS_VMS)
66 #include <sys/timeb.h>
69 static void get_current_time(struct timeval
*t
);
70 const char dtls1_version_str
[]="DTLSv1" OPENSSL_VERSION_PTEXT
;
71 int dtls1_listen(SSL
*s
, struct sockaddr
*client
);
73 SSL3_ENC_METHOD DTLSv1_enc_data
={
77 tls1_generate_master_secret
,
78 tls1_change_cipher_state
,
79 tls1_final_finish_mac
,
80 TLS1_FINISH_MAC_LENGTH
,
82 TLS_MD_CLIENT_FINISH_CONST
,TLS_MD_CLIENT_FINISH_CONST_SIZE
,
83 TLS_MD_SERVER_FINISH_CONST
,TLS_MD_SERVER_FINISH_CONST_SIZE
,
85 tls1_export_keying_material
,
88 long dtls1_default_timeout(void)
90 /* 2 hours, the 24 hours mentioned in the DTLSv1 spec
91 * is way too long for http, the cache would over fill */
99 if (!ssl3_new(s
)) return(0);
100 if ((d1
=OPENSSL_malloc(sizeof *d1
)) == NULL
) return (0);
101 memset(d1
,0, sizeof *d1
);
103 /* d1->handshake_epoch=0; */
105 d1
->unprocessed_rcds
.q
=pqueue_new();
106 d1
->processed_rcds
.q
=pqueue_new();
107 d1
->buffered_messages
= pqueue_new();
108 d1
->sent_messages
=pqueue_new();
109 d1
->buffered_app_data
.q
=pqueue_new();
113 d1
->cookie_len
= sizeof(s
->d1
->cookie
);
116 if( ! d1
->unprocessed_rcds
.q
|| ! d1
->processed_rcds
.q
117 || ! d1
->buffered_messages
|| ! d1
->sent_messages
|| ! d1
->buffered_app_data
.q
)
119 if ( d1
->unprocessed_rcds
.q
) pqueue_free(d1
->unprocessed_rcds
.q
);
120 if ( d1
->processed_rcds
.q
) pqueue_free(d1
->processed_rcds
.q
);
121 if ( d1
->buffered_messages
) pqueue_free(d1
->buffered_messages
);
122 if ( d1
->sent_messages
) pqueue_free(d1
->sent_messages
);
123 if ( d1
->buffered_app_data
.q
) pqueue_free(d1
->buffered_app_data
.q
);
129 s
->method
->ssl_clear(s
);
133 static void dtls1_clear_queues(SSL
*s
)
136 hm_fragment
*frag
= NULL
;
137 DTLS1_RECORD_DATA
*rdata
;
139 while( (item
= pqueue_pop(s
->d1
->unprocessed_rcds
.q
)) != NULL
)
141 rdata
= (DTLS1_RECORD_DATA
*) item
->data
;
144 OPENSSL_free(rdata
->rbuf
.buf
);
146 OPENSSL_free(item
->data
);
150 while( (item
= pqueue_pop(s
->d1
->processed_rcds
.q
)) != NULL
)
152 rdata
= (DTLS1_RECORD_DATA
*) item
->data
;
155 OPENSSL_free(rdata
->rbuf
.buf
);
157 OPENSSL_free(item
->data
);
161 while( (item
= pqueue_pop(s
->d1
->buffered_messages
)) != NULL
)
163 frag
= (hm_fragment
*)item
->data
;
164 OPENSSL_free(frag
->fragment
);
169 while ( (item
= pqueue_pop(s
->d1
->sent_messages
)) != NULL
)
171 frag
= (hm_fragment
*)item
->data
;
172 OPENSSL_free(frag
->fragment
);
177 while ( (item
= pqueue_pop(s
->d1
->buffered_app_data
.q
)) != NULL
)
179 frag
= (hm_fragment
*)item
->data
;
180 OPENSSL_free(frag
->fragment
);
186 void dtls1_free(SSL
*s
)
190 dtls1_clear_queues(s
);
192 pqueue_free(s
->d1
->unprocessed_rcds
.q
);
193 pqueue_free(s
->d1
->processed_rcds
.q
);
194 pqueue_free(s
->d1
->buffered_messages
);
195 pqueue_free(s
->d1
->sent_messages
);
196 pqueue_free(s
->d1
->buffered_app_data
.q
);
201 void dtls1_clear(SSL
*s
)
203 pqueue unprocessed_rcds
;
204 pqueue processed_rcds
;
205 pqueue buffered_messages
;
206 pqueue sent_messages
;
207 pqueue buffered_app_data
;
212 unprocessed_rcds
= s
->d1
->unprocessed_rcds
.q
;
213 processed_rcds
= s
->d1
->processed_rcds
.q
;
214 buffered_messages
= s
->d1
->buffered_messages
;
215 sent_messages
= s
->d1
->sent_messages
;
216 buffered_app_data
= s
->d1
->buffered_app_data
.q
;
219 dtls1_clear_queues(s
);
221 memset(s
->d1
, 0, sizeof(*(s
->d1
)));
225 s
->d1
->cookie_len
= sizeof(s
->d1
->cookie
);
228 if (SSL_get_options(s
) & SSL_OP_NO_QUERY_MTU
)
233 s
->d1
->unprocessed_rcds
.q
= unprocessed_rcds
;
234 s
->d1
->processed_rcds
.q
= processed_rcds
;
235 s
->d1
->buffered_messages
= buffered_messages
;
236 s
->d1
->sent_messages
= sent_messages
;
237 s
->d1
->buffered_app_data
.q
= buffered_app_data
;
241 if (s
->options
& SSL_OP_CISCO_ANYCONNECT
)
242 s
->version
=DTLS1_BAD_VER
;
244 s
->version
=DTLS1_VERSION
;
247 long dtls1_ctrl(SSL
*s
, int cmd
, long larg
, void *parg
)
253 case DTLS_CTRL_GET_TIMEOUT
:
254 if (dtls1_get_timeout(s
, (struct timeval
*) parg
) != NULL
)
259 case DTLS_CTRL_HANDLE_TIMEOUT
:
260 ret
= dtls1_handle_timeout(s
);
262 case DTLS_CTRL_LISTEN
:
263 ret
= dtls1_listen(s
, parg
);
267 ret
= ssl3_ctrl(s
, cmd
, larg
, parg
);
274 * As it's impossible to use stream ciphers in "datagram" mode, this
275 * simple filter is designed to disengage them in DTLS. Unfortunately
276 * there is no universal way to identify stream SSL_CIPHER, so we have
277 * to explicitly list their SSL_* codes. Currently RC4 is the only one
278 * available, but if new ones emerge, they will have to be added...
280 const SSL_CIPHER
*dtls1_get_cipher(unsigned int u
)
282 const SSL_CIPHER
*ciph
= ssl3_get_cipher(u
);
286 if (ciph
->algorithm_enc
== SSL_RC4
)
293 void dtls1_start_timer(SSL
*s
)
295 #ifndef OPENSSL_NO_SCTP
296 /* Disable timer for SCTP */
297 if (BIO_dgram_is_sctp(SSL_get_wbio(s
)))
299 memset(&(s
->d1
->next_timeout
), 0, sizeof(struct timeval
));
304 /* If timer is not set, initialize duration with 1 second */
305 if (s
->d1
->next_timeout
.tv_sec
== 0 && s
->d1
->next_timeout
.tv_usec
== 0)
307 s
->d1
->timeout_duration
= 1;
310 /* Set timeout to current time */
311 get_current_time(&(s
->d1
->next_timeout
));
313 /* Add duration to current time */
314 s
->d1
->next_timeout
.tv_sec
+= s
->d1
->timeout_duration
;
315 BIO_ctrl(SSL_get_rbio(s
), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT
, 0, &(s
->d1
->next_timeout
));
318 struct timeval
* dtls1_get_timeout(SSL
*s
, struct timeval
* timeleft
)
320 struct timeval timenow
;
322 /* If no timeout is set, just return NULL */
323 if (s
->d1
->next_timeout
.tv_sec
== 0 && s
->d1
->next_timeout
.tv_usec
== 0)
328 /* Get current time */
329 get_current_time(&timenow
);
331 /* If timer already expired, set remaining time to 0 */
332 if (s
->d1
->next_timeout
.tv_sec
< timenow
.tv_sec
||
333 (s
->d1
->next_timeout
.tv_sec
== timenow
.tv_sec
&&
334 s
->d1
->next_timeout
.tv_usec
<= timenow
.tv_usec
))
336 memset(timeleft
, 0, sizeof(struct timeval
));
340 /* Calculate time left until timer expires */
341 memcpy(timeleft
, &(s
->d1
->next_timeout
), sizeof(struct timeval
));
342 timeleft
->tv_sec
-= timenow
.tv_sec
;
343 timeleft
->tv_usec
-= timenow
.tv_usec
;
344 if (timeleft
->tv_usec
< 0)
347 timeleft
->tv_usec
+= 1000000;
350 /* If remaining time is less than 15 ms, set it to 0
351 * to prevent issues because of small devergences with
354 if (timeleft
->tv_sec
== 0 && timeleft
->tv_usec
< 15000)
356 memset(timeleft
, 0, sizeof(struct timeval
));
363 int dtls1_is_timer_expired(SSL
*s
)
365 struct timeval timeleft
;
367 /* Get time left until timeout, return false if no timer running */
368 if (dtls1_get_timeout(s
, &timeleft
) == NULL
)
373 /* Return false if timer is not expired yet */
374 if (timeleft
.tv_sec
> 0 || timeleft
.tv_usec
> 0)
379 /* Timer expired, so return true */
383 void dtls1_double_timeout(SSL
*s
)
385 s
->d1
->timeout_duration
*= 2;
386 if (s
->d1
->timeout_duration
> 60)
387 s
->d1
->timeout_duration
= 60;
388 dtls1_start_timer(s
);
391 void dtls1_stop_timer(SSL
*s
)
393 /* Reset everything */
394 memset(&(s
->d1
->timeout
), 0, sizeof(struct dtls1_timeout_st
));
395 memset(&(s
->d1
->next_timeout
), 0, sizeof(struct timeval
));
396 s
->d1
->timeout_duration
= 1;
397 BIO_ctrl(SSL_get_rbio(s
), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT
, 0, &(s
->d1
->next_timeout
));
398 /* Clear retransmission buffer */
399 dtls1_clear_record_buffer(s
);
402 int dtls1_check_timeout_num(SSL
*s
)
404 s
->d1
->timeout
.num_alerts
++;
406 /* Reduce MTU after 2 unsuccessful retransmissions */
407 if (s
->d1
->timeout
.num_alerts
> 2)
409 s
->d1
->mtu
= BIO_ctrl(SSL_get_wbio(s
), BIO_CTRL_DGRAM_GET_FALLBACK_MTU
, 0, NULL
);
412 if (s
->d1
->timeout
.num_alerts
> DTLS1_TMO_ALERT_COUNT
)
414 /* fail the connection, enough alerts have been sent */
415 SSLerr(SSL_F_DTLS1_CHECK_TIMEOUT_NUM
,SSL_R_READ_TIMEOUT_EXPIRED
);
422 int dtls1_handle_timeout(SSL
*s
)
424 /* if no timer is expired, don't do anything */
425 if (!dtls1_is_timer_expired(s
))
430 dtls1_double_timeout(s
);
432 if (dtls1_check_timeout_num(s
) < 0)
435 s
->d1
->timeout
.read_timeouts
++;
436 if (s
->d1
->timeout
.read_timeouts
> DTLS1_TMO_READ_COUNT
)
438 s
->d1
->timeout
.read_timeouts
= 1;
441 #ifndef OPENSSL_NO_HEARTBEATS
442 if (s
->tlsext_hb_pending
)
444 s
->tlsext_hb_pending
= 0;
445 return dtls1_heartbeat(s
);
449 dtls1_start_timer(s
);
450 return dtls1_retransmit_buffered_messages(s
);
453 static void get_current_time(struct timeval
*t
)
455 #ifdef OPENSSL_SYS_WIN32
458 t
->tv_sec
= (long)tb
.time
;
459 t
->tv_usec
= (long)tb
.millitm
* 1000;
460 #elif defined(OPENSSL_SYS_VMS)
463 t
->tv_sec
= (long)tb
.time
;
464 t
->tv_usec
= (long)tb
.millitm
* 1000;
466 gettimeofday(t
, NULL
);
470 int dtls1_listen(SSL
*s
, struct sockaddr
*client
)
474 SSL_set_options(s
, SSL_OP_COOKIE_EXCHANGE
);
478 if (ret
<= 0) return ret
;
480 (void) BIO_dgram_get_peer(SSL_get_rbio(s
), client
);