aboutsummaryrefslogtreecommitdiff
path: root/openssl/ssl/d1_lib.c
blob: 14337b31a4e90708db83f2cd58b307445e88fa50 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
/* ssl/d1_lib.c */
/* 
 * DTLS implementation written by Nagendra Modadugu
 * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.  
 */
/* ====================================================================
 * Copyright (c) 1999-2005 The OpenSSL Project.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer. 
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. All advertising materials mentioning features or use of this
 *    software must display the following acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
 *
 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For written permission, please contact
 *    openssl-core@OpenSSL.org.
 *
 * 5. Products derived from this software may not be called "OpenSSL"
 *    nor may "OpenSSL" appear in their names without prior written
 *    permission of the OpenSSL Project.
 *
 * 6. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
 *
 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 * ====================================================================
 *
 * This product includes cryptographic software written by Eric Young
 * (eay@cryptsoft.com).  This product includes software written by Tim
 * Hudson (tjh@cryptsoft.com).
 *
 */

#include <stdio.h>
#define USE_SOCKETS
#include <openssl/objects.h>
#include "ssl_locl.h"

#if defined(OPENSSL_SYS_WIN32) || defined(OPENSSL_SYS_VMS)
#include <sys/timeb.h>
#endif

static void get_current_time(struct timeval *t);
const char dtls1_version_str[]="DTLSv1" OPENSSL_VERSION_PTEXT;
int dtls1_listen(SSL *s, struct sockaddr *client);

SSL3_ENC_METHOD DTLSv1_enc_data={
    dtls1_enc,
	tls1_mac,
	tls1_setup_key_block,
	tls1_generate_master_secret,
	tls1_change_cipher_state,
	tls1_final_finish_mac,
	TLS1_FINISH_MAC_LENGTH,
	tls1_cert_verify_mac,
	TLS_MD_CLIENT_FINISH_CONST,TLS_MD_CLIENT_FINISH_CONST_SIZE,
	TLS_MD_SERVER_FINISH_CONST,TLS_MD_SERVER_FINISH_CONST_SIZE,
	tls1_alert_code,
	tls1_export_keying_material,
	};

long dtls1_default_timeout(void)
	{
	/* 2 hours, the 24 hours mentioned in the DTLSv1 spec
	 * is way too long for http, the cache would over fill */
	return(60*60*2);
	}

int dtls1_new(SSL *s)
	{
	DTLS1_STATE *d1;

	if (!ssl3_new(s)) return(0);
	if ((d1=OPENSSL_malloc(sizeof *d1)) == NULL) return (0);
	memset(d1,0, sizeof *d1);

	/* d1->handshake_epoch=0; */

	d1->unprocessed_rcds.q=pqueue_new();
	d1->processed_rcds.q=pqueue_new();
	d1->buffered_messages = pqueue_new();
	d1->sent_messages=pqueue_new();
	d1->buffered_app_data.q=pqueue_new();

	if ( s->server)
		{
		d1->cookie_len = sizeof(s->d1->cookie);
		}

	d1->link_mtu = 0;
	d1->mtu = 0;

	if( ! d1->unprocessed_rcds.q || ! d1->processed_rcds.q 
        || ! d1->buffered_messages || ! d1->sent_messages || ! d1->buffered_app_data.q)
		{
        if ( d1->unprocessed_rcds.q) pqueue_free(d1->unprocessed_rcds.q);
        if ( d1->processed_rcds.q) pqueue_free(d1->processed_rcds.q);
        if ( d1->buffered_messages) pqueue_free(d1->buffered_messages);
		if ( d1->sent_messages) pqueue_free(d1->sent_messages);
		if ( d1->buffered_app_data.q) pqueue_free(d1->buffered_app_data.q);
		OPENSSL_free(d1);
		return (0);
		}

	s->d1=d1;
	s->method->ssl_clear(s);
	return(1);
	}

static void dtls1_clear_queues(SSL *s)
	{
    pitem *item = NULL;
    hm_fragment *frag = NULL;
	DTLS1_RECORD_DATA *rdata;

    while( (item = pqueue_pop(s->d1->unprocessed_rcds.q)) != NULL)
        {
		rdata = (DTLS1_RECORD_DATA *) item->data;
		if (rdata->rbuf.buf)
			{
			OPENSSL_free(rdata->rbuf.buf);
			}
        OPENSSL_free(item->data);
        pitem_free(item);
        }

    while( (item = pqueue_pop(s->d1->processed_rcds.q)) != NULL)
        {
		rdata = (DTLS1_RECORD_DATA *) item->data;
		if (rdata->rbuf.buf)
			{
			OPENSSL_free(rdata->rbuf.buf);
			}
        OPENSSL_free(item->data);
        pitem_free(item);
        }

    while( (item = pqueue_pop(s->d1->buffered_messages)) != NULL)
        {
        frag = (hm_fragment *)item->data;
        dtls1_hm_fragment_free(frag);
        pitem_free(item);
        }

    while ( (item = pqueue_pop(s->d1->sent_messages)) != NULL)
        {
        frag = (hm_fragment *)item->data;
        dtls1_hm_fragment_free(frag);
        pitem_free(item);
        }

	while ( (item = pqueue_pop(s->d1->buffered_app_data.q)) != NULL)
		{
		rdata = (DTLS1_RECORD_DATA *) item->data;
		if (rdata->rbuf.buf)
			{
			OPENSSL_free(rdata->rbuf.buf);
			}
		OPENSSL_free(item->data);
		pitem_free(item);
		}
	}

void dtls1_free(SSL *s)
	{
	ssl3_free(s);

	dtls1_clear_queues(s);

    pqueue_free(s->d1->unprocessed_rcds.q);
    pqueue_free(s->d1->processed_rcds.q);
    pqueue_free(s->d1->buffered_messages);
	pqueue_free(s->d1->sent_messages);
	pqueue_free(s->d1->buffered_app_data.q);

	OPENSSL_free(s->d1);
	s->d1 = NULL;
	}

void dtls1_clear(SSL *s)
	{
    pqueue unprocessed_rcds;
    pqueue processed_rcds;
    pqueue buffered_messages;
	pqueue sent_messages;
	pqueue buffered_app_data;
	unsigned int mtu;
	unsigned int link_mtu;

	if (s->d1)
		{
		unprocessed_rcds = s->d1->unprocessed_rcds.q;
		processed_rcds = s->d1->processed_rcds.q;
		buffered_messages = s->d1->buffered_messages;
		sent_messages = s->d1->sent_messages;
		buffered_app_data = s->d1->buffered_app_data.q;
		mtu = s->d1->mtu;
		link_mtu = s->d1->link_mtu;

		dtls1_clear_queues(s);

		memset(s->d1, 0, sizeof(*(s->d1)));

		if (s->server)
			{
			s->d1->cookie_len = sizeof(s->d1->cookie);
			}

		if (SSL_get_options(s) & SSL_OP_NO_QUERY_MTU)
			{
			s->d1->mtu = mtu;
			s->d1->link_mtu = link_mtu;
			}

		s->d1->unprocessed_rcds.q = unprocessed_rcds;
		s->d1->processed_rcds.q = processed_rcds;
		s->d1->buffered_messages = buffered_messages;
		s->d1->sent_messages = sent_messages;
		s->d1->buffered_app_data.q = buffered_app_data;
		}

	ssl3_clear(s);
	if (s->options & SSL_OP_CISCO_ANYCONNECT)
		s->version=DTLS1_BAD_VER;
	else
		s->version=DTLS1_VERSION;
	}

long dtls1_ctrl(SSL *s, int cmd, long larg, void *parg)
	{
	int ret=0;

	switch (cmd)
		{
	case DTLS_CTRL_GET_TIMEOUT:
		if (dtls1_get_timeout(s, (struct timeval*) parg) != NULL)
			{
			ret = 1;
			}
		break;
	case DTLS_CTRL_HANDLE_TIMEOUT:
		ret = dtls1_handle_timeout(s);
		break;
	case DTLS_CTRL_LISTEN:
		ret = dtls1_listen(s, parg);
		break;
	case SSL_CTRL_CHECK_PROTO_VERSION:
		/* For library-internal use; checks that the current protocol
		 * is the highest enabled version (according to s->ctx->method,
		 * as version negotiation may have changed s->method). */
#if DTLS_MAX_VERSION != DTLS1_VERSION
#  error Code needs update for DTLS_method() support beyond DTLS1_VERSION.
#endif
		/* Just one protocol version is supported so far;
		 * fail closed if the version is not as expected. */
		return s->version == DTLS_MAX_VERSION;
	case DTLS_CTRL_SET_LINK_MTU:
		if (larg < (long)dtls1_link_min_mtu())
			return 0;
		s->d1->link_mtu = larg;
		return 1;
	case DTLS_CTRL_GET_LINK_MIN_MTU:
		return (long)dtls1_link_min_mtu();
	case SSL_CTRL_SET_MTU:
		/*
		 *  We may not have a BIO set yet so can't call dtls1_min_mtu()
		 *  We'll have to make do with dtls1_link_min_mtu() and max overhead
		 */
		if (larg < (long)dtls1_link_min_mtu() - DTLS1_MAX_MTU_OVERHEAD)
			return 0;
		s->d1->mtu = larg;
		return larg;
	default:
		ret = ssl3_ctrl(s, cmd, larg, parg);
		break;
		}
	return(ret);
	}

/*
 * As it's impossible to use stream ciphers in "datagram" mode, this
 * simple filter is designed to disengage them in DTLS. Unfortunately
 * there is no universal way to identify stream SSL_CIPHER, so we have
 * to explicitly list their SSL_* codes. Currently RC4 is the only one
 * available, but if new ones emerge, they will have to be added...
 */
const SSL_CIPHER *dtls1_get_cipher(unsigned int u)
	{
	const SSL_CIPHER *ciph = ssl3_get_cipher(u);

	if (ciph != NULL)
		{
		if (ciph->algorithm_enc == SSL_RC4)
			return NULL;
		}

	return ciph;
	}

void dtls1_start_timer(SSL *s)
	{
#ifndef OPENSSL_NO_SCTP
	/* Disable timer for SCTP */
	if (BIO_dgram_is_sctp(SSL_get_wbio(s)))
		{
		memset(&(s->d1->next_timeout), 0, sizeof(struct timeval));
		return;
		}
#endif

	/* If timer is not set, initialize duration with 1 second */
	if (s->d1->next_timeout.tv_sec == 0 && s->d1->next_timeout.tv_usec == 0)
		{
		s->d1->timeout_duration = 1;
		}
	
	/* Set timeout to current time */
	get_current_time(&(s->d1->next_timeout));

	/* Add duration to current time */
	s->d1->next_timeout.tv_sec += s->d1->timeout_duration;
	BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT, 0, &(s->d1->next_timeout));
	}

struct timeval* dtls1_get_timeout(SSL *s, struct timeval* timeleft)
	{
	struct timeval timenow;

	/* If no timeout is set, just return NULL */
	if (s->d1->next_timeout.tv_sec == 0 && s->d1->next_timeout.tv_usec == 0)
		{
		return NULL;
		}

	/* Get current time */
	get_current_time(&timenow);

	/* If timer already expired, set remaining time to 0 */
	if (s->d1->next_timeout.tv_sec < timenow.tv_sec ||
		(s->d1->next_timeout.tv_sec == timenow.tv_sec &&
		 s->d1->next_timeout.tv_usec <= timenow.tv_usec))
		{
		memset(timeleft, 0, sizeof(struct timeval));
		return timeleft;
		}

	/* Calculate time left until timer expires */
	memcpy(timeleft, &(s->d1->next_timeout), sizeof(struct timeval));
	timeleft->tv_sec -= timenow.tv_sec;
	timeleft->tv_usec -= timenow.tv_usec;
	if (timeleft->tv_usec < 0)
		{
		timeleft->tv_sec--;
		timeleft->tv_usec += 1000000;
		}

	/* If remaining time is less than 15 ms, set it to 0
	 * to prevent issues because of small devergences with
	 * socket timeouts.
	 */
	if (timeleft->tv_sec == 0 && timeleft->tv_usec < 15000)
		{
		memset(timeleft, 0, sizeof(struct timeval));
		}
	

	return timeleft;
	}

int dtls1_is_timer_expired(SSL *s)
	{
	struct timeval timeleft;

	/* Get time left until timeout, return false if no timer running */
	if (dtls1_get_timeout(s, &timeleft) == NULL)
		{
		return 0;
		}

	/* Return false if timer is not expired yet */
	if (timeleft.tv_sec > 0 || timeleft.tv_usec > 0)
		{
		return 0;
		}

	/* Timer expired, so return true */	
	return 1;
	}

void dtls1_double_timeout(SSL *s)
	{
	s->d1->timeout_duration *= 2;
	if (s->d1->timeout_duration > 60)
		s->d1->timeout_duration = 60;
	dtls1_start_timer(s);
	}

void dtls1_stop_timer(SSL *s)
	{
	/* Reset everything */
	memset(&(s->d1->timeout), 0, sizeof(struct dtls1_timeout_st));
	memset(&(s->d1->next_timeout), 0, sizeof(struct timeval));
	s->d1->timeout_duration = 1;
	BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT, 0, &(s->d1->next_timeout));
	/* Clear retransmission buffer */
	dtls1_clear_record_buffer(s);
	}

int dtls1_check_timeout_num(SSL *s)
	{
	unsigned int mtu;

	s->d1->timeout.num_alerts++;

	/* Reduce MTU after 2 unsuccessful retransmissions */
	if (s->d1->timeout.num_alerts > 2
			&& !(SSL_get_options(s) & SSL_OP_NO_QUERY_MTU))
		{
		mtu = BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_GET_FALLBACK_MTU, 0, NULL);
		if(mtu < s->d1->mtu)
			s->d1->mtu = mtu;
		}

	if (s->d1->timeout.num_alerts > DTLS1_TMO_ALERT_COUNT)
		{
		/* fail the connection, enough alerts have been sent */
		SSLerr(SSL_F_DTLS1_CHECK_TIMEOUT_NUM,SSL_R_READ_TIMEOUT_EXPIRED);
		return -1;
		}

	return 0;
	}

int dtls1_handle_timeout(SSL *s)
	{
	/* if no timer is expired, don't do anything */
	if (!dtls1_is_timer_expired(s))
		{
		return 0;
		}

	dtls1_double_timeout(s);

	if (dtls1_check_timeout_num(s) < 0)
		return -1;

	s->d1->timeout.read_timeouts++;
	if (s->d1->timeout.read_timeouts > DTLS1_TMO_READ_COUNT)
		{
		s->d1->timeout.read_timeouts = 1;
		}

#ifndef OPENSSL_NO_HEARTBEATS
	if (s->tlsext_hb_pending)
		{
		s->tlsext_hb_pending = 0;
		return dtls1_heartbeat(s);
		}
#endif

	dtls1_start_timer(s);
	return dtls1_retransmit_buffered_messages(s);
	}

static void get_current_time(struct timeval *t)
{
#ifdef OPENSSL_SYS_WIN32
	struct _timeb tb;
	_ftime(&tb);
	t->tv_sec = (long)tb.time;
	t->tv_usec = (long)tb.millitm * 1000;
#elif defined(OPENSSL_SYS_VMS)
	struct timeb tb;
	ftime(&tb);
	t->tv_sec = (long)tb.time;
	t->tv_usec = (long)tb.millitm * 1000;
#else
	gettimeofday(t, NULL);
#endif
}

int dtls1_listen(SSL *s, struct sockaddr *client)
	{
	int ret;

	SSL_set_options(s, SSL_OP_COOKIE_EXCHANGE);
	s->d1->listen = 1;

	ret = SSL_accept(s);
	if (ret <= 0) return ret;
	
	(void) BIO_dgram_get_peer(SSL_get_rbio(s), client);
	return 1;
	}