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
|
/*
* Copyright (C) 2012 Free Software Foundation, Inc.
*
* Author: Nikos Mavrogiannopoulos
*
* 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
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#if defined(_WIN32)
int main()
{
exit(77);
}
#else
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <gnutls/gnutls.h>
#include <gnutls/dtls.h>
#include <signal.h>
#include "utils.h"
/* This program tests whether a DTLS handshake would timeout
* in a minute.
*/
static void print_type(const unsigned char* buf, int size)
{
if (buf[0] == 22 && size >= 13) {
if (buf[13] == 1)
fprintf(stderr, "Client Hello\n");
else if (buf[13] == 2)
fprintf(stderr, "Server Hello\n");
else if (buf[13] == 12)
fprintf(stderr, "Server Key exchange\n");
else if (buf[13] == 14)
fprintf(stderr, "Server Hello Done\n");
else if (buf[13] == 11)
fprintf(stderr, "Certificate\n");
else if (buf[13] == 16)
fprintf(stderr, "Client Key Exchange\n");
else if (buf[4] == 1)
fprintf(stderr, "Finished\n");
else if (buf[13] == 11)
fprintf(stderr, "Server Hello Done\n");
else
fprintf(stderr, "Unknown handshake\n");
} else if (buf[0] == 20) {
fprintf(stderr, "Change Cipher Spec\n");
} else
fprintf(stderr, "Unknown\n");
}
static void
server_log_func (int level, const char *str)
{
fprintf (stderr, "server|<%d>| %s", level, str);
}
static void
client_log_func (int level, const char *str)
{
fprintf (stderr, "client|<%d>| %s", level, str);
}
/* A very basic TLS client, with anonymous authentication.
*/
static int counter;
static int packet_to_lose;
gnutls_session_t session;
static ssize_t
push (gnutls_transport_ptr_t tr, const void *data, size_t len)
{
int fd = (long int)tr;
counter++;
if (packet_to_lose != -1 && packet_to_lose == counter) {
if (debug)
{
fprintf(stderr, "Discarding packet %d: ", counter);
print_type(data, len);
}
packet_to_lose = 1;
counter = 0;
return len;
}
return send(fd, data, len, 0);
}
static void
client (int fd, int packet)
{
int ret;
gnutls_anon_client_credentials_t anoncred;
/* Need to enable anonymous KX specifically. */
gnutls_global_init ();
if (debug)
{
gnutls_global_set_log_function (client_log_func);
gnutls_global_set_log_level (4711);
}
gnutls_anon_allocate_client_credentials (&anoncred);
/* Initialize TLS session
*/
gnutls_init (&session, GNUTLS_CLIENT|GNUTLS_DATAGRAM);
gnutls_dtls_set_mtu( session, 1500);
/* Use default priorities */
gnutls_priority_set_direct (session, "NONE:+VERS-DTLS1.0:+CIPHER-ALL:+MAC-ALL:+SIGN-ALL:+COMP-ALL:+ANON-ECDH:+CURVE-ALL", NULL);
/* put the anonymous credentials to the current session
*/
gnutls_credentials_set (session, GNUTLS_CRD_ANON, anoncred);
counter = 0;
packet_to_lose = packet;
gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) fd);
gnutls_transport_set_push_function (session, push);
/* Perform the TLS handshake
*/
do
{
ret = gnutls_handshake (session);
}
while (ret < 0 && gnutls_error_is_fatal(ret) == 0);
gnutls_deinit(session);
gnutls_global_deinit();
if (ret < 0)
{
if (ret == GNUTLS_E_TIMEDOUT) return;
fail ("client: Handshake failed\n");
gnutls_perror (ret);
exit(1);
}
else
{
if (debug)
success ("client: Handshake was completed\n");
}
exit(1);
}
/* These are global */
gnutls_anon_server_credentials_t anoncred;
pid_t child;
static gnutls_session_t
initialize_tls_session (void)
{
gnutls_session_t session;
gnutls_init (&session, GNUTLS_SERVER|GNUTLS_DATAGRAM);
gnutls_dtls_set_mtu( session, 1500);
/* avoid calling all the priority functions, since the defaults
* are adequate.
*/
gnutls_priority_set_direct (session, "NONE:+VERS-DTLS1.0:+CIPHER-ALL:+MAC-ALL:+SIGN-ALL:+COMP-ALL:+ANON-ECDH:+CURVE-ALL", NULL);
gnutls_credentials_set (session, GNUTLS_CRD_ANON, anoncred);
return session;
}
static void
server (int fd, int packet)
{
int ret;
/* this must be called once in the program
*/
gnutls_global_init ();
if (debug)
{
gnutls_global_set_log_function (server_log_func);
gnutls_global_set_log_level (4711);
}
gnutls_anon_allocate_server_credentials (&anoncred);
session = initialize_tls_session ();
counter = 0;
packet_to_lose = packet;
gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) fd);
gnutls_transport_set_push_function (session, push);
do
{
ret = gnutls_handshake (session);
}
while (ret < 0 && gnutls_error_is_fatal(ret) == 0);
gnutls_deinit (session);
gnutls_global_deinit();
if (ret < 0)
{
return;
}
}
static void start (int server_packet, int client_packet)
{
int fd[2];
int ret;
if (debug)
fprintf(stderr, "\nWill discard %s packet %d\n",
(client_packet!=-1)?"client":"server", (client_packet!=-1)?client_packet:server_packet);
ret = socketpair(AF_UNIX, SOCK_DGRAM, 0, fd);
if (ret < 0)
{
perror("socketpair");
exit(1);
}
child = fork ();
if (child < 0)
{
perror ("fork");
fail ("fork");
exit(1);
}
if (child)
{
/* parent */
close(fd[1]);
server (fd[0], server_packet);
close(fd[0]);
}
else
{
close(fd[0]);
client (fd[1], client_packet);
close(fd[1]);
exit(0);
}
}
static void ch_handler(int sig)
{
int status;
wait(&status);
if (WEXITSTATUS(status) != 0)
fail("Child died with status %d\n", WEXITSTATUS(status));
return;
}
void
doit (void)
{
time_t tstart, tstop;
signal(SIGCHLD, ch_handler);
tstart = time(0);
start(2, -1);
tstop = time(0);
tstop = tstop - tstart;
if (!(tstop < 70 && tstop > 55))
fail("Time difference: %u\n", (unsigned)tstop);
}
#endif /* _WIN32 */
|