reject zero length point format list or supported curves extensions
[openssl.git] / ssl / d1_lib.c
1 /* ssl/d1_lib.c */
2 /* 
3  * DTLS implementation written by Nagendra Modadugu
4  * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.  
5  */
6 /* ====================================================================
7  * Copyright (c) 1999-2005 The OpenSSL Project.  All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  *
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer. 
15  *
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
19  *    distribution.
20  *
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/)"
25  *
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.
30  *
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.
34  *
35  * 6. Redistributions of any form whatsoever must retain the following
36  *    acknowledgment:
37  *    "This product includes software developed by the OpenSSL Project
38  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
39  *
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  * ====================================================================
53  *
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).
57  *
58  */
59
60 #include <stdio.h>
61 #define USE_SOCKETS
62 #include <openssl/objects.h>
63 #include "ssl_locl.h"
64
65 #if defined(OPENSSL_SYS_WIN32) || defined(OPENSSL_SYS_VMS)
66 #include <sys/timeb.h>
67 #endif
68
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);
72
73 SSL3_ENC_METHOD DTLSv1_enc_data={
74     dtls1_enc,
75         tls1_mac,
76         tls1_setup_key_block,
77         tls1_generate_master_secret,
78         tls1_change_cipher_state,
79         tls1_final_finish_mac,
80         TLS1_FINISH_MAC_LENGTH,
81         tls1_cert_verify_mac,
82         TLS_MD_CLIENT_FINISH_CONST,TLS_MD_CLIENT_FINISH_CONST_SIZE,
83         TLS_MD_SERVER_FINISH_CONST,TLS_MD_SERVER_FINISH_CONST_SIZE,
84         tls1_alert_code,
85         tls1_export_keying_material,
86         };
87
88 long dtls1_default_timeout(void)
89         {
90         /* 2 hours, the 24 hours mentioned in the DTLSv1 spec
91          * is way too long for http, the cache would over fill */
92         return(60*60*2);
93         }
94
95 int dtls1_new(SSL *s)
96         {
97         DTLS1_STATE *d1;
98
99         if (!ssl3_new(s)) return(0);
100         if ((d1=OPENSSL_malloc(sizeof *d1)) == NULL) return (0);
101         memset(d1,0, sizeof *d1);
102
103         /* d1->handshake_epoch=0; */
104
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();
110
111         if ( s->server)
112                 {
113                 d1->cookie_len = sizeof(s->d1->cookie);
114                 }
115
116         if( ! d1->unprocessed_rcds.q || ! d1->processed_rcds.q 
117         || ! d1->buffered_messages || ! d1->sent_messages || ! d1->buffered_app_data.q)
118                 {
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);
124                 OPENSSL_free(d1);
125                 return (0);
126                 }
127
128         s->d1=d1;
129         s->method->ssl_clear(s);
130         return(1);
131         }
132
133 static void dtls1_clear_queues(SSL *s)
134         {
135     pitem *item = NULL;
136     hm_fragment *frag = NULL;
137         DTLS1_RECORD_DATA *rdata;
138
139     while( (item = pqueue_pop(s->d1->unprocessed_rcds.q)) != NULL)
140         {
141                 rdata = (DTLS1_RECORD_DATA *) item->data;
142                 if (rdata->rbuf.buf)
143                         {
144                         OPENSSL_free(rdata->rbuf.buf);
145                         }
146         OPENSSL_free(item->data);
147         pitem_free(item);
148         }
149
150     while( (item = pqueue_pop(s->d1->processed_rcds.q)) != NULL)
151         {
152                 rdata = (DTLS1_RECORD_DATA *) item->data;
153                 if (rdata->rbuf.buf)
154                         {
155                         OPENSSL_free(rdata->rbuf.buf);
156                         }
157         OPENSSL_free(item->data);
158         pitem_free(item);
159         }
160
161     while( (item = pqueue_pop(s->d1->buffered_messages)) != NULL)
162         {
163         frag = (hm_fragment *)item->data;
164         OPENSSL_free(frag->fragment);
165         OPENSSL_free(frag);
166         pitem_free(item);
167         }
168
169     while ( (item = pqueue_pop(s->d1->sent_messages)) != NULL)
170         {
171         frag = (hm_fragment *)item->data;
172         OPENSSL_free(frag->fragment);
173         OPENSSL_free(frag);
174         pitem_free(item);
175         }
176
177         while ( (item = pqueue_pop(s->d1->buffered_app_data.q)) != NULL)
178                 {
179                 frag = (hm_fragment *)item->data;
180                 OPENSSL_free(frag->fragment);
181                 OPENSSL_free(frag);
182                 pitem_free(item);
183                 }
184         }
185
186 void dtls1_free(SSL *s)
187         {
188         ssl3_free(s);
189
190         dtls1_clear_queues(s);
191
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);
197
198         OPENSSL_free(s->d1);
199         }
200
201 void dtls1_clear(SSL *s)
202         {
203     pqueue unprocessed_rcds;
204     pqueue processed_rcds;
205     pqueue buffered_messages;
206         pqueue sent_messages;
207         pqueue buffered_app_data;
208         unsigned int mtu;
209
210         if (s->d1)
211                 {
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;
217                 mtu = s->d1->mtu;
218
219                 dtls1_clear_queues(s);
220
221                 memset(s->d1, 0, sizeof(*(s->d1)));
222
223                 if (s->server)
224                         {
225                         s->d1->cookie_len = sizeof(s->d1->cookie);
226                         }
227
228                 if (SSL_get_options(s) & SSL_OP_NO_QUERY_MTU)
229                         {
230                         s->d1->mtu = mtu;
231                         }
232
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;
238                 }
239
240         ssl3_clear(s);
241         if (s->options & SSL_OP_CISCO_ANYCONNECT)
242                 s->version=DTLS1_BAD_VER;
243         else
244                 s->version=DTLS1_VERSION;
245         }
246
247 long dtls1_ctrl(SSL *s, int cmd, long larg, void *parg)
248         {
249         int ret=0;
250
251         switch (cmd)
252                 {
253         case DTLS_CTRL_GET_TIMEOUT:
254                 if (dtls1_get_timeout(s, (struct timeval*) parg) != NULL)
255                         {
256                         ret = 1;
257                         }
258                 break;
259         case DTLS_CTRL_HANDLE_TIMEOUT:
260                 ret = dtls1_handle_timeout(s);
261                 break;
262         case DTLS_CTRL_LISTEN:
263                 ret = dtls1_listen(s, parg);
264                 break;
265
266         default:
267                 ret = ssl3_ctrl(s, cmd, larg, parg);
268                 break;
269                 }
270         return(ret);
271         }
272
273 /*
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...
279  */
280 const SSL_CIPHER *dtls1_get_cipher(unsigned int u)
281         {
282         const SSL_CIPHER *ciph = ssl3_get_cipher(u);
283
284         if (ciph != NULL)
285                 {
286                 if (ciph->algorithm_enc == SSL_RC4)
287                         return NULL;
288                 }
289
290         return ciph;
291         }
292
293 void dtls1_start_timer(SSL *s)
294         {
295 #ifndef OPENSSL_NO_SCTP
296         /* Disable timer for SCTP */
297         if (BIO_dgram_is_sctp(SSL_get_wbio(s)))
298                 {
299                 memset(&(s->d1->next_timeout), 0, sizeof(struct timeval));
300                 return;
301                 }
302 #endif
303
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)
306                 {
307                 s->d1->timeout_duration = 1;
308                 }
309         
310         /* Set timeout to current time */
311         get_current_time(&(s->d1->next_timeout));
312
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));
316         }
317
318 struct timeval* dtls1_get_timeout(SSL *s, struct timeval* timeleft)
319         {
320         struct timeval timenow;
321
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)
324                 {
325                 return NULL;
326                 }
327
328         /* Get current time */
329         get_current_time(&timenow);
330
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))
335                 {
336                 memset(timeleft, 0, sizeof(struct timeval));
337                 return timeleft;
338                 }
339
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)
345                 {
346                 timeleft->tv_sec--;
347                 timeleft->tv_usec += 1000000;
348                 }
349
350         /* If remaining time is less than 15 ms, set it to 0
351          * to prevent issues because of small devergences with
352          * socket timeouts.
353          */
354         if (timeleft->tv_sec == 0 && timeleft->tv_usec < 15000)
355                 {
356                 memset(timeleft, 0, sizeof(struct timeval));
357                 }
358         
359
360         return timeleft;
361         }
362
363 int dtls1_is_timer_expired(SSL *s)
364         {
365         struct timeval timeleft;
366
367         /* Get time left until timeout, return false if no timer running */
368         if (dtls1_get_timeout(s, &timeleft) == NULL)
369                 {
370                 return 0;
371                 }
372
373         /* Return false if timer is not expired yet */
374         if (timeleft.tv_sec > 0 || timeleft.tv_usec > 0)
375                 {
376                 return 0;
377                 }
378
379         /* Timer expired, so return true */     
380         return 1;
381         }
382
383 void dtls1_double_timeout(SSL *s)
384         {
385         s->d1->timeout_duration *= 2;
386         if (s->d1->timeout_duration > 60)
387                 s->d1->timeout_duration = 60;
388         dtls1_start_timer(s);
389         }
390
391 void dtls1_stop_timer(SSL *s)
392         {
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);
400         }
401
402 int dtls1_check_timeout_num(SSL *s)
403         {
404         s->d1->timeout.num_alerts++;
405
406         /* Reduce MTU after 2 unsuccessful retransmissions */
407         if (s->d1->timeout.num_alerts > 2)
408                 {
409                 s->d1->mtu = BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_GET_FALLBACK_MTU, 0, NULL);               
410                 }
411
412         if (s->d1->timeout.num_alerts > DTLS1_TMO_ALERT_COUNT)
413                 {
414                 /* fail the connection, enough alerts have been sent */
415                 SSLerr(SSL_F_DTLS1_CHECK_TIMEOUT_NUM,SSL_R_READ_TIMEOUT_EXPIRED);
416                 return -1;
417                 }
418
419         return 0;
420         }
421
422 int dtls1_handle_timeout(SSL *s)
423         {
424         /* if no timer is expired, don't do anything */
425         if (!dtls1_is_timer_expired(s))
426                 {
427                 return 0;
428                 }
429
430         dtls1_double_timeout(s);
431
432         if (dtls1_check_timeout_num(s) < 0)
433                 return -1;
434
435         s->d1->timeout.read_timeouts++;
436         if (s->d1->timeout.read_timeouts > DTLS1_TMO_READ_COUNT)
437                 {
438                 s->d1->timeout.read_timeouts = 1;
439                 }
440
441 #ifndef OPENSSL_NO_HEARTBEATS
442         if (s->tlsext_hb_pending)
443                 {
444                 s->tlsext_hb_pending = 0;
445                 return dtls1_heartbeat(s);
446                 }
447 #endif
448
449         dtls1_start_timer(s);
450         return dtls1_retransmit_buffered_messages(s);
451         }
452
453 static void get_current_time(struct timeval *t)
454 {
455 #ifdef OPENSSL_SYS_WIN32
456         struct _timeb tb;
457         _ftime(&tb);
458         t->tv_sec = (long)tb.time;
459         t->tv_usec = (long)tb.millitm * 1000;
460 #elif defined(OPENSSL_SYS_VMS)
461         struct timeb tb;
462         ftime(&tb);
463         t->tv_sec = (long)tb.time;
464         t->tv_usec = (long)tb.millitm * 1000;
465 #else
466         gettimeofday(t, NULL);
467 #endif
468 }
469
470 int dtls1_listen(SSL *s, struct sockaddr *client)
471         {
472         int ret;
473
474         SSL_set_options(s, SSL_OP_COOKIE_EXCHANGE);
475         s->d1->listen = 1;
476
477         ret = SSL_accept(s);
478         if (ret <= 0) return ret;
479         
480         (void) BIO_dgram_get_peer(SSL_get_rbio(s), client);
481         return 1;
482         }