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
|
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <getopt.h>
#include <xtables.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter/xt_NFLOG.h>
enum {
NFLOG_GROUP = 0x1,
NFLOG_PREFIX = 0x2,
NFLOG_RANGE = 0x4,
NFLOG_THRESHOLD = 0x8,
};
static const struct option NFLOG_opts[] = {
{ "nflog-group", 1, NULL, NFLOG_GROUP },
{ "nflog-prefix", 1, NULL, NFLOG_PREFIX },
{ "nflog-range", 1, NULL, NFLOG_RANGE },
{ "nflog-threshold", 1, NULL, NFLOG_THRESHOLD },
{ .name = NULL }
};
static void NFLOG_help(void)
{
printf("NFLOG target options:\n"
" --nflog-group NUM NETLINK group used for logging\n"
" --nflog-range NUM Number of byte to copy\n"
" --nflog-threshold NUM Message threshold of in-kernel queue\n"
" --nflog-prefix STRING Prefix string for log messages\n");
}
static void NFLOG_init(struct xt_entry_target *t)
{
struct xt_nflog_info *info = (struct xt_nflog_info *)t->data;
info->group = 0;
info->threshold = XT_NFLOG_DEFAULT_THRESHOLD;
}
static int NFLOG_parse(int c, char **argv, int invert, unsigned int *flags,
const void *entry, struct xt_entry_target **target)
{
struct xt_nflog_info *info = (struct xt_nflog_info *)(*target)->data;
int n;
size_t length;
switch (c) {
case NFLOG_GROUP:
if (*flags & NFLOG_GROUP)
xtables_error(PARAMETER_PROBLEM,
"Can't specify --nflog-group twice");
if (xtables_check_inverse(optarg, &invert, NULL, 0, argv))
xtables_error(PARAMETER_PROBLEM,
"Unexpected `!' after --nflog-group");
n = atoi(optarg);
if (n < 0)
xtables_error(PARAMETER_PROBLEM,
"--nflog-group can not be negative");
info->group = n;
break;
case NFLOG_PREFIX:
if (*flags & NFLOG_PREFIX)
xtables_error(PARAMETER_PROBLEM,
"Can't specify --nflog-prefix twice");
if (xtables_check_inverse(optarg, &invert, NULL, 0, argv))
xtables_error(PARAMETER_PROBLEM,
"Unexpected `!' after --nflog-prefix");
length = strlen(optarg);
if (length == 0)
xtables_error(PARAMETER_PROBLEM,
"No prefix specified for --nflog-prefix");
if (length >= sizeof(info->prefix))
xtables_error(PARAMETER_PROBLEM,
"--nflog-prefix too long, max %Zu characters",
sizeof(info->prefix) - 1);
if (length != strlen(strtok(optarg, "\n")))
xtables_error(PARAMETER_PROBLEM,
"Newlines are not allowed in --nflog-prefix");
strcpy(info->prefix, optarg);
break;
case NFLOG_RANGE:
if (*flags & NFLOG_RANGE)
xtables_error(PARAMETER_PROBLEM,
"Can't specify --nflog-range twice");
n = atoi(optarg);
if (n < 0)
xtables_error(PARAMETER_PROBLEM,
"Invalid --nflog-range, must be >= 0");
info->len = n;
break;
case NFLOG_THRESHOLD:
if (*flags & NFLOG_THRESHOLD)
xtables_error(PARAMETER_PROBLEM,
"Can't specify --nflog-threshold twice");
n = atoi(optarg);
if (n < 1)
xtables_error(PARAMETER_PROBLEM,
"Invalid --nflog-threshold, must be >= 1");
info->threshold = n;
break;
default:
return 0;
}
*flags |= c;
return 1;
}
static void nflog_print(const struct xt_nflog_info *info, char *prefix)
{
if (info->prefix[0] != '\0') {
printf("%snflog-prefix ", prefix);
xtables_save_string(info->prefix);
}
if (info->group)
printf("%snflog-group %u ", prefix, info->group);
if (info->len)
printf("%snflog-range %u ", prefix, info->len);
if (info->threshold != XT_NFLOG_DEFAULT_THRESHOLD)
printf("%snflog-threshold %u ", prefix, info->threshold);
}
static void NFLOG_print(const void *ip, const struct xt_entry_target *target,
int numeric)
{
const struct xt_nflog_info *info = (struct xt_nflog_info *)target->data;
nflog_print(info, "");
}
static void NFLOG_save(const void *ip, const struct xt_entry_target *target)
{
const struct xt_nflog_info *info = (struct xt_nflog_info *)target->data;
nflog_print(info, "--");
}
static struct xtables_target nflog_target = {
.family = NFPROTO_UNSPEC,
.name = "NFLOG",
.version = XTABLES_VERSION,
.size = XT_ALIGN(sizeof(struct xt_nflog_info)),
.userspacesize = XT_ALIGN(sizeof(struct xt_nflog_info)),
.help = NFLOG_help,
.init = NFLOG_init,
.parse = NFLOG_parse,
.print = NFLOG_print,
.save = NFLOG_save,
.extra_opts = NFLOG_opts,
};
void _init(void)
{
xtables_register_target(&nflog_target);
}
|
