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
|
/*
* OpenVPN -- An application to securely tunnel IP networks
* over a single TCP/UDP port, with support for SSL/TLS-based
* session authentication and key exchange,
* packet encryption, packet authentication, and
* packet compression.
*
* Copyright (C) 2002-2017 OpenVPN Technologies, Inc. <sales@openvpn.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation.
*
* This program 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 this program (see the file COPYING included with this
* distribution); if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#elif defined(_MSC_VER)
#include "config-msvc.h"
#endif
#include "syshead.h"
#include "ping.h"
#include "memdbg.h"
#include "ping-inline.h"
/*
* This random string identifies an OpenVPN ping packet.
* It should be of sufficient length and randomness
* so as not to collide with other tunnel data.
*
* PING_STRING_SIZE must be sizeof (ping_string)
*/
const uint8_t ping_string[] = {
0x2a, 0x18, 0x7b, 0xf3, 0x64, 0x1e, 0xb4, 0xcb,
0x07, 0xed, 0x2d, 0x0a, 0x98, 0x1f, 0xc7, 0x48
};
/*
* Should we exit or restart due to ping (or other authenticated packet)
* not received in n seconds?
*/
void
check_ping_restart_dowork(struct context *c)
{
struct gc_arena gc = gc_new();
switch (c->options.ping_rec_timeout_action)
{
case PING_EXIT:
msg(M_INFO, "%sInactivity timeout (--ping-exit), exiting",
format_common_name(c, &gc));
c->sig->signal_received = SIGTERM;
c->sig->signal_text = "ping-exit";
break;
case PING_RESTART:
msg(M_INFO, "%sInactivity timeout (--ping-restart), restarting",
format_common_name(c, &gc));
c->sig->signal_received = SIGUSR1; /* SOFT-SIGUSR1 -- Ping Restart */
c->sig->signal_text = "ping-restart";
break;
default:
ASSERT(0);
}
gc_free(&gc);
}
/*
* Should we ping the remote?
*/
void
check_ping_send_dowork(struct context *c)
{
c->c2.buf = c->c2.buffers->aux_buf;
ASSERT(buf_init(&c->c2.buf, FRAME_HEADROOM(&c->c2.frame)));
ASSERT(buf_safe(&c->c2.buf, MAX_RW_SIZE_TUN(&c->c2.frame)));
ASSERT(buf_write(&c->c2.buf, ping_string, sizeof(ping_string)));
/*
* We will treat the ping like any other outgoing packet,
* encrypt, sign, etc.
*/
encrypt_sign(c, true);
/* Set length to 0, so it won't be counted as activity */
c->c2.buf.len = 0;
dmsg(D_PING, "SENT PING");
}
|
