1 #include <stdbool.h>
2 #include <stdlib.h>
3 #include <stdio.h>
4 #include <string.h>
5 #include <getopt.h>
6 #include <xtables.h>
7
8 #include <linux/netfilter/x_tables.h>
9 #include <linux/netfilter/xt_NFLOG.h>
10
11 enum {
12 O_GROUP = 0,
13 O_PREFIX,
14 O_RANGE,
15 O_THRESHOLD,
16 };
17
18 #define s struct xt_nflog_info
19 static const struct xt_option_entry NFLOG_opts[] = {
20 {.name = "nflog-group", .id = O_GROUP, .type = XTTYPE_UINT16,
21 .flags = XTOPT_PUT, XTOPT_POINTER(s, group)},
22 {.name = "nflog-prefix", .id = O_PREFIX, .type = XTTYPE_STRING,
23 .min = 1, .flags = XTOPT_PUT, XTOPT_POINTER(s, prefix)},
24 {.name = "nflog-range", .id = O_RANGE, .type = XTTYPE_UINT32,
25 .flags = XTOPT_PUT, XTOPT_POINTER(s, len)},
26 {.name = "nflog-threshold", .id = O_THRESHOLD, .type = XTTYPE_UINT16,
27 .flags = XTOPT_PUT, XTOPT_POINTER(s, threshold)},
28 XTOPT_TABLEEND,
29 };
30 #undef s
31
NFLOG_help(void)32 static void NFLOG_help(void)
33 {
34 printf("NFLOG target options:\n"
35 " --nflog-group NUM NETLINK group used for logging\n"
36 " --nflog-range NUM Number of byte to copy\n"
37 " --nflog-threshold NUM Message threshold of in-kernel queue\n"
38 " --nflog-prefix STRING Prefix string for log messages\n");
39 }
40
NFLOG_init(struct xt_entry_target * t)41 static void NFLOG_init(struct xt_entry_target *t)
42 {
43 struct xt_nflog_info *info = (struct xt_nflog_info *)t->data;
44
45 info->threshold = XT_NFLOG_DEFAULT_THRESHOLD;
46 }
47
NFLOG_parse(struct xt_option_call * cb)48 static void NFLOG_parse(struct xt_option_call *cb)
49 {
50 xtables_option_parse(cb);
51 switch (cb->entry->id) {
52 case O_PREFIX:
53 if (strchr(cb->arg, '\n') != NULL)
54 xtables_error(PARAMETER_PROBLEM,
55 "Newlines not allowed in --log-prefix");
56 break;
57 }
58 }
59
nflog_print(const struct xt_nflog_info * info,char * prefix)60 static void nflog_print(const struct xt_nflog_info *info, char *prefix)
61 {
62 if (info->prefix[0] != '\0') {
63 printf(" %snflog-prefix ", prefix);
64 xtables_save_string(info->prefix);
65 }
66 if (info->group)
67 printf(" %snflog-group %u", prefix, info->group);
68 if (info->len)
69 printf(" %snflog-range %u", prefix, info->len);
70 if (info->threshold != XT_NFLOG_DEFAULT_THRESHOLD)
71 printf(" %snflog-threshold %u", prefix, info->threshold);
72 }
73
NFLOG_print(const void * ip,const struct xt_entry_target * target,int numeric)74 static void NFLOG_print(const void *ip, const struct xt_entry_target *target,
75 int numeric)
76 {
77 const struct xt_nflog_info *info = (struct xt_nflog_info *)target->data;
78
79 nflog_print(info, "");
80 }
81
NFLOG_save(const void * ip,const struct xt_entry_target * target)82 static void NFLOG_save(const void *ip, const struct xt_entry_target *target)
83 {
84 const struct xt_nflog_info *info = (struct xt_nflog_info *)target->data;
85
86 nflog_print(info, "--");
87 }
88
89 static struct xtables_target nflog_target = {
90 .family = NFPROTO_UNSPEC,
91 .name = "NFLOG",
92 .version = XTABLES_VERSION,
93 .size = XT_ALIGN(sizeof(struct xt_nflog_info)),
94 .userspacesize = XT_ALIGN(sizeof(struct xt_nflog_info)),
95 .help = NFLOG_help,
96 .init = NFLOG_init,
97 .x6_parse = NFLOG_parse,
98 .print = NFLOG_print,
99 .save = NFLOG_save,
100 .x6_options = NFLOG_opts,
101 };
102
_init(void)103 void _init(void)
104 {
105 xtables_register_target(&nflog_target);
106 }
107