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
|
/*
* libipt_osf.c
*
* Copyright (c) 2003 Evgeniy Polyakov <johnpol@2ka.mipt.ru>
*
*
* This program 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 2 of the License, or
* (at your option) any later version.
*
* 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; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
* iptables interface for OS fingerprint matching module.
*/
#include <stdio.h>
#include <netdb.h>
#include <string.h>
#include <stdlib.h>
#include <getopt.h>
#include <ctype.h>
#include <iptables.h>
#include <linux/netfilter_ipv4/ipt_osf.h>
static void help(void)
{
printf("OS fingerprint match v%s options:\n"
"--genre [!] string Match a OS genre by passive fingerprinting.\n"
"--smart Use some smart extensions to determine OS (do not use TTL).\n"
"--log level Log all(or only first) determined genres even if "
"they do not match desired one. "
"Level may be 0(all) or 1(only first entry).\n"
"--netlink Log through netlink(NETLINK_NFLOG).\n",
IPTABLES_VERSION);
}
static struct option opts[] = {
{ .name = "genre", .has_arg = 1, .flag = 0, .val = '1' },
{ .name = "smart", .has_arg = 0, .flag = 0, .val = '2' },
{ .name = "log", .has_arg = 1, .flag = 0, .val = '3' },
{ .name = "netlink", .has_arg = 0, .flag = 0, .val = '4' },
{ .name = 0 }
};
static void init(struct ipt_entry_match *m, unsigned int *nfcache)
{
*nfcache |= NFC_UNKNOWN;
}
static void parse_string(const unsigned char *s, struct ipt_osf_info *info)
{
if (strlen(s) < MAXGENRELEN)
strcpy(info->genre, s);
else
exit_error(PARAMETER_PROBLEM, "Genre string too long `%s' [%d], max=%d",
s, strlen(s), MAXGENRELEN);
}
static int parse(int c, char **argv, int invert, unsigned int *flags,
const struct ipt_entry *entry,
unsigned int *nfcache,
struct ipt_entry_match **match)
{
struct ipt_osf_info *info = (struct ipt_osf_info *)(*match)->data;
switch(c)
{
case '1': /* --genre */
if (*flags & IPT_OSF_GENRE)
exit_error(PARAMETER_PROBLEM, "Can't specify multiple genre parameter");
check_inverse(optarg, &invert, &optind, 0);
parse_string(argv[optind-1], info);
if (invert)
info->invert = 1;
info->len=strlen((char *)info->genre);
*flags |= IPT_OSF_GENRE;
break;
case '2': /* --smart */
if (*flags & IPT_OSF_SMART)
exit_error(PARAMETER_PROBLEM, "Can't specify multiple smart parameter");
*flags |= IPT_OSF_SMART;
info->flags |= IPT_OSF_SMART;
break;
case '3': /* --log */
if (*flags & IPT_OSF_LOG)
exit_error(PARAMETER_PROBLEM, "Can't specify multiple log parameter");
*flags |= IPT_OSF_LOG;
info->loglevel = atoi(argv[optind-1]);
info->flags |= IPT_OSF_LOG;
break;
case '4': /* --netlink */
if (*flags & IPT_OSF_NETLINK)
exit_error(PARAMETER_PROBLEM, "Can't specify multiple smart parameter");
*flags |= IPT_OSF_NETLINK;
info->flags |= IPT_OSF_NETLINK;
break;
default:
return 0;
}
return 1;
}
static void final_check(unsigned int flags)
{
if (!flags)
exit_error(PARAMETER_PROBLEM, "OS fingerprint match: You must specify `--genre'");
}
static void print(const struct ipt_ip *ip, const struct ipt_entry_match *match, int numeric)
{
const struct ipt_osf_info *info = (const struct ipt_osf_info*) match->data;
printf("OS fingerprint match %s%s ", (info->invert) ? "!" : "", info->genre);
}
static void save(const struct ipt_ip *ip, const struct ipt_entry_match *match)
{
const struct ipt_osf_info *info = (const struct ipt_osf_info*) match->data;
printf("--genre %s%s ", (info->invert) ? "! ": "", info->genre);
}
static struct iptables_match osf_match = {
.name = "osf",
.version = IPTABLES_VERSION,
.size = IPT_ALIGN(sizeof(struct ipt_osf_info)),
.userspacesize = IPT_ALIGN(sizeof(struct ipt_osf_info)),
.help = &help,
.init = &init,
.parse = &parse,
.final_check = &final_check,
.print = &print,
.save = &save,
.extra_opts = opts
};
void _init(void)
{
register_match(&osf_match);
}
|
