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,
87 long dtls1_default_timeout(void)
90 * 2 hours, the 24 hours mentioned in the DTLSv1 spec is way too long for
91 * http, the cache would over fill
96 IMPLEMENT_dtls1_meth_func(dtlsv1_base_method,
97 ssl_undefined_function,
98 ssl_undefined_function, ssl_bad_method)
100 int dtls1_new(SSL *s)
106 if ((d1 = OPENSSL_malloc(sizeof *d1)) == NULL)
108 memset(d1, 0, sizeof *d1);
110 /* d1->handshake_epoch=0; */
111 #if defined(OPENSSL_SYS_VMS) || defined(VMS_TEST)
112 d1->bitmap.length = 64;
114 d1->bitmap.length = sizeof(d1->bitmap.map) * 8;
116 pq_64bit_init(&(d1->bitmap.map));
117 pq_64bit_init(&(d1->bitmap.max_seq_num));
119 d1->next_bitmap.length = d1->bitmap.length;
120 pq_64bit_init(&(d1->next_bitmap.map));
121 pq_64bit_init(&(d1->next_bitmap.max_seq_num));
123 d1->unprocessed_rcds.q = pqueue_new();
124 d1->processed_rcds.q = pqueue_new();
125 d1->buffered_messages = pqueue_new();
126 d1->sent_messages = pqueue_new();
127 d1->buffered_app_data.q = pqueue_new();
130 d1->cookie_len = sizeof(s->d1->cookie);
133 if (!d1->unprocessed_rcds.q || !d1->processed_rcds.q
134 || !d1->buffered_messages || !d1->sent_messages
135 || !d1->buffered_app_data.q) {
136 if (d1->unprocessed_rcds.q)
137 pqueue_free(d1->unprocessed_rcds.q);
138 if (d1->processed_rcds.q)
139 pqueue_free(d1->processed_rcds.q);
140 if (d1->buffered_messages)
141 pqueue_free(d1->buffered_messages);
142 if (d1->sent_messages)
143 pqueue_free(d1->sent_messages);
144 if (d1->buffered_app_data.q)
145 pqueue_free(d1->buffered_app_data.q);
151 s->method->ssl_clear(s);
155 static void dtls1_clear_queues(SSL *s)
158 hm_fragment *frag = NULL;
159 DTLS1_RECORD_DATA *rdata;
161 while ((item = pqueue_pop(s->d1->unprocessed_rcds.q)) != NULL) {
162 rdata = (DTLS1_RECORD_DATA *)item->data;
163 if (rdata->rbuf.buf) {
164 OPENSSL_free(rdata->rbuf.buf);
166 OPENSSL_free(item->data);
170 while ((item = pqueue_pop(s->d1->processed_rcds.q)) != NULL) {
171 rdata = (DTLS1_RECORD_DATA *)item->data;
172 if (rdata->rbuf.buf) {
173 OPENSSL_free(rdata->rbuf.buf);
175 OPENSSL_free(item->data);
179 while ((item = pqueue_pop(s->d1->buffered_messages)) != NULL) {
180 frag = (hm_fragment *)item->data;
181 OPENSSL_free(frag->fragment);
186 while ((item = pqueue_pop(s->d1->sent_messages)) != NULL) {
187 frag = (hm_fragment *)item->data;
188 OPENSSL_free(frag->fragment);
193 while ((item = pqueue_pop(s->d1->buffered_app_data.q)) != NULL) {
194 rdata = (DTLS1_RECORD_DATA *)item->data;
195 if (rdata->rbuf.buf) {
196 OPENSSL_free(rdata->rbuf.buf);
198 OPENSSL_free(item->data);
203 void dtls1_free(SSL *s)
207 dtls1_clear_queues(s);
209 pqueue_free(s->d1->unprocessed_rcds.q);
210 pqueue_free(s->d1->processed_rcds.q);
211 pqueue_free(s->d1->buffered_messages);
212 pqueue_free(s->d1->sent_messages);
213 pqueue_free(s->d1->buffered_app_data.q);
215 pq_64bit_free(&(s->d1->bitmap.map));
216 pq_64bit_free(&(s->d1->bitmap.max_seq_num));
218 pq_64bit_free(&(s->d1->next_bitmap.map));
219 pq_64bit_free(&(s->d1->next_bitmap.max_seq_num));
225 void dtls1_clear(SSL *s)
227 pqueue unprocessed_rcds;
228 pqueue processed_rcds;
229 pqueue buffered_messages;
230 pqueue sent_messages;
231 pqueue buffered_app_data;
235 unprocessed_rcds = s->d1->unprocessed_rcds.q;
236 processed_rcds = s->d1->processed_rcds.q;
237 buffered_messages = s->d1->buffered_messages;
238 sent_messages = s->d1->sent_messages;
239 buffered_app_data = s->d1->buffered_app_data.q;
242 dtls1_clear_queues(s);
244 pq_64bit_free(&(s->d1->bitmap.map));
245 pq_64bit_free(&(s->d1->bitmap.max_seq_num));
247 pq_64bit_free(&(s->d1->next_bitmap.map));
248 pq_64bit_free(&(s->d1->next_bitmap.max_seq_num));
250 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) {
260 s->d1->unprocessed_rcds.q = unprocessed_rcds;
261 s->d1->processed_rcds.q = processed_rcds;
262 s->d1->buffered_messages = buffered_messages;
263 s->d1->sent_messages = sent_messages;
264 s->d1->buffered_app_data.q = buffered_app_data;
266 #if defined(OPENSSL_SYS_VMS) || defined(VMS_TEST)
267 s->d1->bitmap.length = 64;
269 s->d1->bitmap.length = sizeof(s->d1->bitmap.map) * 8;
271 pq_64bit_init(&(s->d1->bitmap.map));
272 pq_64bit_init(&(s->d1->bitmap.max_seq_num));
274 s->d1->next_bitmap.length = s->d1->bitmap.length;
275 pq_64bit_init(&(s->d1->next_bitmap.map));
276 pq_64bit_init(&(s->d1->next_bitmap.max_seq_num));
280 if (s->options & SSL_OP_CISCO_ANYCONNECT)
281 s->version = DTLS1_BAD_VER;
283 s->version = DTLS1_VERSION;
286 long dtls1_ctrl(SSL *s, int cmd, long larg, void *parg)
291 case DTLS_CTRL_GET_TIMEOUT:
292 if (dtls1_get_timeout(s, (struct timeval *)parg) != NULL) {
296 case DTLS_CTRL_HANDLE_TIMEOUT:
297 ret = dtls1_handle_timeout(s);
299 case DTLS_CTRL_LISTEN:
300 ret = dtls1_listen(s, parg);
302 case SSL_CTRL_CHECK_PROTO_VERSION:
304 * For library-internal use; checks that the current protocol is the
305 * highest enabled version (according to s->ctx->method, as version
306 * negotiation may have changed s->method).
308 #if DTLS_MAX_VERSION != DTLS1_VERSION
309 # error Code needs update for DTLS_method() support beyond DTLS1_VERSION.
312 * Just one protocol version is supported so far; fail closed if the
313 * version is not as expected.
315 return s->version == DTLS_MAX_VERSION;
318 ret = ssl3_ctrl(s, cmd, larg, parg);
325 * As it's impossible to use stream ciphers in "datagram" mode, this
326 * simple filter is designed to disengage them in DTLS. Unfortunately
327 * there is no universal way to identify stream SSL_CIPHER, so we have
328 * to explicitly list their SSL_* codes. Currently RC4 is the only one
329 * available, but if new ones emerge, they will have to be added...
331 SSL_CIPHER *dtls1_get_cipher(unsigned int u)
333 SSL_CIPHER *ciph = ssl3_get_cipher(u);
336 if ((ciph->algorithms & SSL_ENC_MASK) == SSL_RC4)
343 void dtls1_start_timer(SSL *s)
345 /* If timer is not set, initialize duration with 1 second */
346 if (s->d1->next_timeout.tv_sec == 0 && s->d1->next_timeout.tv_usec == 0) {
347 s->d1->timeout_duration = 1;
350 /* Set timeout to current time */
351 get_current_time(&(s->d1->next_timeout));
353 /* Add duration to current time */
354 s->d1->next_timeout.tv_sec += s->d1->timeout_duration;
355 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT, 0,
356 &(s->d1->next_timeout));
359 struct timeval *dtls1_get_timeout(SSL *s, struct timeval *timeleft)
361 struct timeval timenow;
363 /* If no timeout is set, just return NULL */
364 if (s->d1->next_timeout.tv_sec == 0 && s->d1->next_timeout.tv_usec == 0) {
368 /* Get current time */
369 get_current_time(&timenow);
371 /* If timer already expired, set remaining time to 0 */
372 if (s->d1->next_timeout.tv_sec < timenow.tv_sec ||
373 (s->d1->next_timeout.tv_sec == timenow.tv_sec &&
374 s->d1->next_timeout.tv_usec <= timenow.tv_usec)) {
375 memset(timeleft, 0, sizeof(struct timeval));
379 /* Calculate time left until timer expires */
380 memcpy(timeleft, &(s->d1->next_timeout), sizeof(struct timeval));
381 timeleft->tv_sec -= timenow.tv_sec;
382 timeleft->tv_usec -= timenow.tv_usec;
383 if (timeleft->tv_usec < 0) {
385 timeleft->tv_usec += 1000000;
389 * If remaining time is less than 15 ms, set it to 0 to prevent issues
390 * because of small devergences with socket timeouts.
392 if (timeleft->tv_sec == 0 && timeleft->tv_usec < 15000) {
393 memset(timeleft, 0, sizeof(struct timeval));
399 int dtls1_is_timer_expired(SSL *s)
401 struct timeval timeleft;
403 /* Get time left until timeout, return false if no timer running */
404 if (dtls1_get_timeout(s, &timeleft) == NULL) {
408 /* Return false if timer is not expired yet */
409 if (timeleft.tv_sec > 0 || timeleft.tv_usec > 0) {
413 /* Timer expired, so return true */
417 void dtls1_double_timeout(SSL *s)
419 s->d1->timeout_duration *= 2;
420 if (s->d1->timeout_duration > 60)
421 s->d1->timeout_duration = 60;
422 dtls1_start_timer(s);
425 void dtls1_stop_timer(SSL *s)
427 /* Reset everything */
428 memset(&(s->d1->timeout), 0, sizeof(struct dtls1_timeout_st));
429 memset(&(s->d1->next_timeout), 0, sizeof(struct timeval));
430 s->d1->timeout_duration = 1;
431 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT, 0,
432 &(s->d1->next_timeout));
433 /* Clear retransmission buffer */
434 dtls1_clear_record_buffer(s);
437 int dtls1_check_timeout_num(SSL *s)
439 s->d1->timeout.num_alerts++;
441 /* Reduce MTU after 2 unsuccessful retransmissions */
442 if (s->d1->timeout.num_alerts > 2) {
444 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_GET_FALLBACK_MTU, 0,
448 if (s->d1->timeout.num_alerts > DTLS1_TMO_ALERT_COUNT) {
449 /* fail the connection, enough alerts have been sent */
450 SSLerr(SSL_F_DTLS1_CHECK_TIMEOUT_NUM, SSL_R_READ_TIMEOUT_EXPIRED);
457 int dtls1_handle_timeout(SSL *s)
459 /* if no timer is expired, don't do anything */
460 if (!dtls1_is_timer_expired(s)) {
464 dtls1_double_timeout(s);
466 if (dtls1_check_timeout_num(s) < 0)
469 s->d1->timeout.read_timeouts++;
470 if (s->d1->timeout.read_timeouts > DTLS1_TMO_READ_COUNT) {
471 s->d1->timeout.read_timeouts = 1;
474 dtls1_start_timer(s);
475 return dtls1_retransmit_buffered_messages(s);
478 static void get_current_time(struct timeval *t)
480 #ifdef OPENSSL_SYS_WIN32
483 t->tv_sec = (long)tb.time;
484 t->tv_usec = (long)tb.millitm * 1000;
485 #elif defined(OPENSSL_SYS_VMS)
488 t->tv_sec = (long)tb.time;
489 t->tv_usec = (long)tb.millitm * 1000;
491 gettimeofday(t, NULL);
495 int dtls1_listen(SSL *s, struct sockaddr *client)
499 /* Ensure there is no state left over from a previous invocation */
502 SSL_set_options(s, SSL_OP_COOKIE_EXCHANGE);
509 (void)BIO_dgram_get_peer(SSL_get_rbio(s), client);