1 /* Shared library add-on to ip6tables to add customized REJECT support.
2 *
3 * (C) 2000 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
4 *
5 * ported to IPv6 by Harald Welte <laforge@gnumonks.org>
6 *
7 */
8 #include <stdio.h>
9 #include <string.h>
10 #include <xtables.h>
11 #include <linux/netfilter_ipv6/ip6t_REJECT.h>
12
13 struct reject_names {
14 const char *name;
15 const char *alias;
16 enum ip6t_reject_with with;
17 const char *desc;
18 };
19
20 enum {
21 O_REJECT_WITH = 0,
22 };
23
24 static const struct reject_names reject_table[] = {
25 {"icmp6-no-route", "no-route",
26 IP6T_ICMP6_NO_ROUTE, "ICMPv6 no route"},
27 {"icmp6-adm-prohibited", "adm-prohibited",
28 IP6T_ICMP6_ADM_PROHIBITED, "ICMPv6 administratively prohibited"},
29 #if 0
30 {"icmp6-not-neighbor", "not-neighbor"},
31 IP6T_ICMP6_NOT_NEIGHBOR, "ICMPv6 not a neighbor"},
32 #endif
33 {"icmp6-addr-unreachable", "addr-unreach",
34 IP6T_ICMP6_ADDR_UNREACH, "ICMPv6 address unreachable"},
35 {"icmp6-port-unreachable", "port-unreach",
36 IP6T_ICMP6_PORT_UNREACH, "ICMPv6 port unreachable"},
37 {"tcp-reset", "tcp-reset",
38 IP6T_TCP_RESET, "TCP RST packet"}
39 };
40
41 static void
print_reject_types(void)42 print_reject_types(void)
43 {
44 unsigned int i;
45
46 printf("Valid reject types:\n");
47
48 for (i = 0; i < ARRAY_SIZE(reject_table); ++i) {
49 printf(" %-25s\t%s\n", reject_table[i].name, reject_table[i].desc);
50 printf(" %-25s\talias\n", reject_table[i].alias);
51 }
52 printf("\n");
53 }
54
REJECT_help(void)55 static void REJECT_help(void)
56 {
57 printf(
58 "REJECT target options:\n"
59 "--reject-with type drop input packet and send back\n"
60 " a reply packet according to type:\n");
61
62 print_reject_types();
63 }
64
65 static const struct xt_option_entry REJECT_opts[] = {
66 {.name = "reject-with", .id = O_REJECT_WITH, .type = XTTYPE_STRING},
67 XTOPT_TABLEEND,
68 };
69
REJECT_init(struct xt_entry_target * t)70 static void REJECT_init(struct xt_entry_target *t)
71 {
72 struct ip6t_reject_info *reject = (struct ip6t_reject_info *)t->data;
73
74 /* default */
75 reject->with = IP6T_ICMP6_PORT_UNREACH;
76
77 }
78
REJECT_parse(struct xt_option_call * cb)79 static void REJECT_parse(struct xt_option_call *cb)
80 {
81 struct ip6t_reject_info *reject = cb->data;
82 unsigned int i;
83
84 xtables_option_parse(cb);
85 for (i = 0; i < ARRAY_SIZE(reject_table); ++i)
86 if (strncasecmp(reject_table[i].name,
87 cb->arg, strlen(cb->arg)) == 0 ||
88 strncasecmp(reject_table[i].alias,
89 cb->arg, strlen(cb->arg)) == 0) {
90 reject->with = reject_table[i].with;
91 return;
92 }
93 xtables_error(PARAMETER_PROBLEM,
94 "unknown reject type \"%s\"", cb->arg);
95 }
96
REJECT_print(const void * ip,const struct xt_entry_target * target,int numeric)97 static void REJECT_print(const void *ip, const struct xt_entry_target *target,
98 int numeric)
99 {
100 const struct ip6t_reject_info *reject
101 = (const struct ip6t_reject_info *)target->data;
102 unsigned int i;
103
104 for (i = 0; i < ARRAY_SIZE(reject_table); ++i)
105 if (reject_table[i].with == reject->with)
106 break;
107 printf(" reject-with %s", reject_table[i].name);
108 }
109
REJECT_save(const void * ip,const struct xt_entry_target * target)110 static void REJECT_save(const void *ip, const struct xt_entry_target *target)
111 {
112 const struct ip6t_reject_info *reject
113 = (const struct ip6t_reject_info *)target->data;
114 unsigned int i;
115
116 for (i = 0; i < ARRAY_SIZE(reject_table); ++i)
117 if (reject_table[i].with == reject->with)
118 break;
119
120 printf(" --reject-with %s", reject_table[i].name);
121 }
122
123 static struct xtables_target reject_tg6_reg = {
124 .name = "REJECT",
125 .version = XTABLES_VERSION,
126 .family = NFPROTO_IPV6,
127 .size = XT_ALIGN(sizeof(struct ip6t_reject_info)),
128 .userspacesize = XT_ALIGN(sizeof(struct ip6t_reject_info)),
129 .help = REJECT_help,
130 .init = REJECT_init,
131 .print = REJECT_print,
132 .save = REJECT_save,
133 .x6_parse = REJECT_parse,
134 .x6_options = REJECT_opts,
135 };
136
_init(void)137 void _init(void)
138 {
139 xtables_register_target(&reject_tg6_reg);
140 }
141