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
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
|
/*
* Copyright (C) 2004, 2005, 2007, 2008, 2009, 2010 Free Software
* Foundation, Inc.
*
* Author: Simon Josefsson
*
* This file is part of GnuTLS.
*
* GnuTLS is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* GnuTLS is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GnuTLS; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
/* Parts copied from GnuTLS example programs. */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <gnutls/gnutls.h>
#include "tcp.c"
#include "utils.h"
static void wrap_db_init (void);
static void wrap_db_deinit (void);
static int wrap_db_store (void *dbf, gnutls_datum_t key, gnutls_datum_t data);
static gnutls_datum_t wrap_db_fetch (void *dbf, gnutls_datum_t key);
static int wrap_db_delete (void *dbf, gnutls_datum_t key);
#define TLS_SESSION_CACHE 50
struct params_res
{
const char *desc;
int enable_db;
int enable_session_ticket_server;
int enable_session_ticket_client;
int expect_resume;
};
pid_t child;
struct params_res resume_tests[] = {
{"try to resume from db", 50, 0, 0, 1},
#ifdef ENABLE_SESSION_TICKET
{"try to resume from session ticket", 0, 1, 1, 1},
{"try to resume from session ticket (server only)", 0, 1, 0, 0},
{"try to resume from session ticket (client only)", 0, 0, 1, 0},
#endif
{NULL, -1}
};
/* A very basic TLS client, with anonymous authentication.
*/
#define MAX_BUF 1024
#define MSG "Hello TLS"
static void
tls_log_func (int level, const char *str)
{
fprintf (stderr, "%s |<%d>| %s", child ? "server" : "client", level, str);
}
static void
client (struct params_res *params)
{
int ret, sd, ii;
gnutls_session_t session;
char buffer[MAX_BUF + 1];
gnutls_anon_client_credentials_t anoncred;
/* Need to enable anonymous KX specifically. */
const int kx_prio[] = { GNUTLS_KX_ANON_DH, 0 };
/* variables used in session resuming
*/
int t;
gnutls_datum_t session_data;
if (debug)
{
gnutls_global_set_log_function (tls_log_func);
gnutls_global_set_log_level (2);
}
gnutls_global_init ();
gnutls_anon_allocate_client_credentials (&anoncred);
for (t = 0; t < 2; t++)
{ /* connect 2 times to the server */
/* connect to the peer
*/
sd = tcp_connect ();
/* Initialize TLS session
*/
gnutls_init (&session, GNUTLS_CLIENT);
/* Use default priorities */
gnutls_set_default_priority (session);
gnutls_kx_set_priority (session, kx_prio);
/* put the anonymous credentials to the current session
*/
gnutls_credentials_set (session, GNUTLS_CRD_ANON, anoncred);
#ifdef ENABLE_SESSION_TICKET
if (params->enable_session_ticket_client)
gnutls_session_ticket_enable_client (session);
#endif
if (t > 0)
{
/* if this is not the first time we connect */
gnutls_session_set_data (session, session_data.data,
session_data.size);
gnutls_free (session_data.data);
}
gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) sd);
/* Perform the TLS handshake
*/
ret = gnutls_handshake (session);
if (ret < 0)
{
fail ("client: Handshake failed\n");
gnutls_perror (ret);
goto end;
}
else
{
if (debug)
success ("client: Handshake was completed\n");
}
if (t == 0)
{ /* the first time we connect */
/* get the session data size */
ret = gnutls_session_get_data2 (session, &session_data);
if (ret < 0)
fail ("Getting resume data failed\n");
}
else
{ /* the second time we connect */
/* check if we actually resumed the previous session */
if (gnutls_session_is_resumed (session) != 0)
{
if (params->expect_resume)
{
if (debug)
success ("- Previous session was resumed\n");
}
else
fail ("- Previous session was resumed\n");
}
else
{
if (params->expect_resume)
fail ("*** Previous session was NOT resumed\n");
else
{
if (debug)
success
("*** Previous session was NOT resumed (expected)\n");
}
}
}
gnutls_record_send (session, MSG, strlen (MSG));
ret = gnutls_record_recv (session, buffer, MAX_BUF);
if (ret == 0)
{
if (debug)
success ("client: Peer has closed the TLS connection\n");
goto end;
}
else if (ret < 0)
{
fail ("client: Error: %s\n", gnutls_strerror (ret));
goto end;
}
if (debug)
{
printf ("- Received %d bytes: ", ret);
for (ii = 0; ii < ret; ii++)
{
fputc (buffer[ii], stdout);
}
fputs ("\n", stdout);
}
gnutls_bye (session, GNUTLS_SHUT_RDWR);
tcp_close (sd);
gnutls_deinit (session);
}
end:
gnutls_anon_free_client_credentials (anoncred);
}
/* This is a sample TLS 1.0 echo server, for anonymous authentication only.
*/
#define SA struct sockaddr
#define MAX_BUF 1024
#define PORT 5556 /* listen to 5556 port */
#define DH_BITS 1024
/* These are global */
gnutls_anon_server_credentials_t anoncred;
gnutls_datum_t session_ticket_key = { NULL, 0 };
static gnutls_session_t
initialize_tls_session (struct params_res *params)
{
gnutls_session_t session;
const int kx_prio[] = { GNUTLS_KX_ANON_DH, 0 };
gnutls_init (&session, GNUTLS_SERVER);
/* avoid calling all the priority functions, since the defaults
* are adequate.
*/
gnutls_set_default_priority (session);
gnutls_kx_set_priority (session, kx_prio);
gnutls_credentials_set (session, GNUTLS_CRD_ANON, anoncred);
gnutls_dh_set_prime_bits (session, DH_BITS);
if (params->enable_db)
{
gnutls_db_set_retrieve_function (session, wrap_db_fetch);
gnutls_db_set_remove_function (session, wrap_db_delete);
gnutls_db_set_store_function (session, wrap_db_store);
gnutls_db_set_ptr (session, NULL);
}
#ifdef ENABLE_SESSION_TICKET
if (params->enable_session_ticket_server)
gnutls_session_ticket_enable_server (session, &session_ticket_key);
#endif
return session;
}
static gnutls_dh_params_t dh_params;
static int
generate_dh_params (void)
{
const gnutls_datum_t p3 = { (char *) pkcs3, strlen (pkcs3) };
/* Generate Diffie-Hellman parameters - for use with DHE
* kx algorithms. These should be discarded and regenerated
* once a day, once a week or once a month. Depending on the
* security requirements.
*/
gnutls_dh_params_init (&dh_params);
return gnutls_dh_params_import_pkcs3 (dh_params, &p3, GNUTLS_X509_FMT_PEM);
}
int err, listen_sd, i;
int sd, ret;
struct sockaddr_in sa_serv;
struct sockaddr_in sa_cli;
int client_len;
char topbuf[512];
gnutls_session_t session;
char buffer[MAX_BUF + 1];
int optval = 1;
static void
global_start (void)
{
/* Socket operations
*/
listen_sd = socket (AF_INET, SOCK_STREAM, 0);
if (err == -1)
{
perror ("socket");
fail ("server: socket failed\n");
return;
}
memset (&sa_serv, '\0', sizeof (sa_serv));
sa_serv.sin_family = AF_INET;
sa_serv.sin_addr.s_addr = INADDR_ANY;
sa_serv.sin_port = htons (PORT); /* Server Port number */
setsockopt (listen_sd, SOL_SOCKET, SO_REUSEADDR, (void *) &optval,
sizeof (int));
err = bind (listen_sd, (SA *) & sa_serv, sizeof (sa_serv));
if (err == -1)
{
perror ("bind");
fail ("server: bind failed\n");
return;
}
err = listen (listen_sd, 1024);
if (err == -1)
{
perror ("listen");
fail ("server: listen failed\n");
return;
}
if (debug)
success ("server: ready. Listening to port '%d'.\n", PORT);
}
static void
global_stop (void)
{
if (debug)
success ("global stop\n");
gnutls_anon_free_server_credentials (anoncred);
gnutls_dh_params_deinit (dh_params);
gnutls_global_deinit ();
shutdown (listen_sd, SHUT_RDWR);
}
static void
server (struct params_res *params)
{
size_t t;
/* this must be called once in the program, it is mostly for the server.
*/
if (debug)
{
gnutls_global_set_log_function (tls_log_func);
gnutls_global_set_log_level (2);
}
gnutls_global_init ();
gnutls_anon_allocate_server_credentials (&anoncred);
if (debug)
success ("Launched, generating DH parameters...\n");
generate_dh_params ();
gnutls_anon_set_server_dh_params (anoncred, dh_params);
if (params->enable_db)
{
wrap_db_init ();
}
#ifdef ENABLE_SESSION_TICKET
if (params->enable_session_ticket_server)
gnutls_session_ticket_key_generate (&session_ticket_key);
#endif
for (t = 0; t < 2; t++)
{
client_len = sizeof (sa_cli);
session = initialize_tls_session (params);
sd = accept (listen_sd, (SA *) & sa_cli, &client_len);
if (debug)
success ("server: connection from %s, port %d\n",
inet_ntop (AF_INET, &sa_cli.sin_addr, topbuf,
sizeof (topbuf)), ntohs (sa_cli.sin_port));
gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) sd);
ret = gnutls_handshake (session);
if (ret < 0)
{
close (sd);
gnutls_deinit (session);
fail ("server: Handshake has failed (%s)\n\n",
gnutls_strerror (ret));
return;
}
if (debug)
success ("server: Handshake was completed\n");
/* see the Getting peer's information example */
/* print_info(session); */
i = 0;
for (;;)
{
memset (buffer, 0, MAX_BUF + 1);
ret = gnutls_record_recv (session, buffer, MAX_BUF);
if (ret == 0)
{
if (debug)
success ("server: Peer has closed the GnuTLS connection\n");
break;
}
else if (ret < 0)
{
fail ("server: Received corrupted data(%d). Closing...\n", ret);
break;
}
else if (ret > 0)
{
/* echo data back to the client
*/
gnutls_record_send (session, buffer, strlen (buffer));
}
}
/* do not wait for the peer to close the connection.
*/
gnutls_bye (session, GNUTLS_SHUT_WR);
close (sd);
gnutls_deinit (session);
}
close (listen_sd);
if (params->enable_db)
{
wrap_db_deinit ();
}
gnutls_free (session_ticket_key.data);
session_ticket_key.data = NULL;
if (debug)
success ("server: finished\n");
}
void
doit (void)
{
int i;
for (i = 0; resume_tests[i].desc; i++)
{
if (debug)
printf ("%s\n", resume_tests[i].desc);
global_start ();
if (error_count)
return;
child = fork ();
if (child < 0)
{
perror ("fork");
fail ("fork");
return;
}
if (child)
{
int status;
/* parent */
server (&resume_tests[i]);
wait (&status);
global_stop ();
}
else
{
client (&resume_tests[i]);
gnutls_global_deinit ();
exit (0);
}
}
}
/* Functions and other stuff needed for session resuming.
* This is done using a very simple list which holds session ids
* and session data.
*/
#define MAX_SESSION_ID_SIZE 32
#define MAX_SESSION_DATA_SIZE 512
typedef struct
{
unsigned char session_id[MAX_SESSION_ID_SIZE];
unsigned int session_id_size;
char session_data[MAX_SESSION_DATA_SIZE];
int session_data_size;
} CACHE;
static CACHE *cache_db;
static int cache_db_ptr = 0;
static void
wrap_db_init (void)
{
/* allocate cache_db */
cache_db = calloc (1, TLS_SESSION_CACHE * sizeof (CACHE));
}
static void
wrap_db_deinit (void)
{
free (cache_db);
cache_db = NULL;
return;
}
static int
wrap_db_store (void *dbf, gnutls_datum_t key, gnutls_datum_t data)
{
if (debug)
success ("resume db storing... (%d-%d)\n", key.size, data.size);
if (debug)
{
unsigned int i;
printf ("key:\n");
for (i = 0; i < key.size; i++)
{
printf ("%02x ", key.data[i] & 0xFF);
if ((i + 1) % 16 == 0)
printf ("\n");
}
printf ("\n");
printf ("data:\n");
for (i = 0; i < data.size; i++)
{
printf ("%02x ", data.data[i] & 0xFF);
if ((i + 1) % 16 == 0)
printf ("\n");
}
printf ("\n");
}
if (cache_db == NULL)
return -1;
if (key.size > MAX_SESSION_ID_SIZE)
return -1;
if (data.size > MAX_SESSION_DATA_SIZE)
return -1;
memcpy (cache_db[cache_db_ptr].session_id, key.data, key.size);
cache_db[cache_db_ptr].session_id_size = key.size;
memcpy (cache_db[cache_db_ptr].session_data, data.data, data.size);
cache_db[cache_db_ptr].session_data_size = data.size;
cache_db_ptr++;
cache_db_ptr %= TLS_SESSION_CACHE;
return 0;
}
static gnutls_datum_t
wrap_db_fetch (void *dbf, gnutls_datum_t key)
{
gnutls_datum_t res = { NULL, 0 };
int i;
if (debug)
success ("resume db fetch... (%d)\n", key.size);
if (debug)
{
unsigned int i;
printf ("key:\n");
for (i = 0; i < key.size; i++)
{
printf ("%02x ", key.data[i] & 0xFF);
if ((i + 1) % 16 == 0)
printf ("\n");
}
printf ("\n");
}
if (cache_db == NULL)
return res;
for (i = 0; i < TLS_SESSION_CACHE; i++)
{
if (key.size == cache_db[i].session_id_size &&
memcmp (key.data, cache_db[i].session_id, key.size) == 0)
{
if (debug)
success ("resume db fetch... return info\n");
res.size = cache_db[i].session_data_size;
res.data = gnutls_malloc (res.size);
if (res.data == NULL)
return res;
memcpy (res.data, cache_db[i].session_data, res.size);
if (debug)
{
unsigned int i;
printf ("data:\n");
for (i = 0; i < res.size; i++)
{
printf ("%02x ", res.data[i] & 0xFF);
if ((i + 1) % 16 == 0)
printf ("\n");
}
printf ("\n");
}
return res;
}
}
return res;
}
static int
wrap_db_delete (void *dbf, gnutls_datum_t key)
{
int i;
if (cache_db == NULL)
return -1;
for (i = 0; i < TLS_SESSION_CACHE; i++)
{
if (key.size == cache_db[i].session_id_size &&
memcmp (key.data, cache_db[i].session_id, key.size) == 0)
{
cache_db[i].session_id_size = 0;
cache_db[i].session_data_size = 0;
return 0;
}
}
return -1;
}
|