1 #include <stdio.h>
2 #include <string.h>
3 #include <stdlib.h>
4 #include <errno.h>
5 #if defined(__GLIBC__) && __GLIBC__ == 2
6 #include <net/ethernet.h>
7 #else
8 #include <linux/if_ether.h>
9 #endif
10 #include <xtables.h>
11 #include <linux/netfilter_ipv4/ipt_realm.h>
12
13 enum {
14 O_REALM = 0,
15 };
16
realm_help(void)17 static void realm_help(void)
18 {
19 printf(
20 "realm match options:\n"
21 "[!] --realm value[/mask]\n"
22 " Match realm\n");
23 }
24
25 static const struct xt_option_entry realm_opts[] = {
26 {.name = "realm", .id = O_REALM, .type = XTTYPE_STRING,
27 .flags = XTOPT_MAND | XTOPT_INVERT},
28 XTOPT_TABLEEND,
29 };
30
31 /* array of realms from /etc/iproute2/rt_realms */
32 static struct xtables_lmap *realms;
33
realm_init(struct xt_entry_match * m)34 static void realm_init(struct xt_entry_match *m)
35 {
36 const char file[] = "/etc/iproute2/rt_realms";
37 realms = xtables_lmap_init(file);
38 if (realms == NULL && errno != ENOENT)
39 fprintf(stderr, "Warning: %s: %s\n", file, strerror(errno));
40 }
41
realm_parse(struct xt_option_call * cb)42 static void realm_parse(struct xt_option_call *cb)
43 {
44 struct xt_realm_info *realminfo = cb->data;
45 int id;
46 char *end;
47
48 xtables_option_parse(cb);
49 realminfo->id = strtoul(cb->arg, &end, 0);
50 if (end != cb->arg && (*end == '/' || *end == '\0')) {
51 if (*end == '/')
52 realminfo->mask = strtoul(end+1, &end, 0);
53 else
54 realminfo->mask = 0xffffffff;
55 if (*end != '\0' || end == cb->arg)
56 xtables_error(PARAMETER_PROBLEM,
57 "Bad realm value \"%s\"", cb->arg);
58 } else {
59 id = xtables_lmap_name2id(realms, cb->arg);
60 if (id == -1)
61 xtables_error(PARAMETER_PROBLEM,
62 "Realm \"%s\" not found", cb->arg);
63 realminfo->id = id;
64 realminfo->mask = 0xffffffff;
65 }
66 if (cb->invert)
67 realminfo->invert = 1;
68 }
69
70 static void
print_realm(unsigned long id,unsigned long mask,int numeric)71 print_realm(unsigned long id, unsigned long mask, int numeric)
72 {
73 const char* name = NULL;
74
75 if (mask != 0xffffffff)
76 printf(" 0x%lx/0x%lx", id, mask);
77 else {
78 if (numeric == 0)
79 name = xtables_lmap_id2name(realms, id);
80 if (name)
81 printf(" %s", name);
82 else
83 printf(" 0x%lx", id);
84 }
85 }
86
realm_print(const void * ip,const struct xt_entry_match * match,int numeric)87 static void realm_print(const void *ip, const struct xt_entry_match *match,
88 int numeric)
89 {
90 const struct xt_realm_info *ri = (const void *)match->data;
91
92 if (ri->invert)
93 printf(" !");
94
95 printf(" realm");
96 print_realm(ri->id, ri->mask, numeric);
97 }
98
realm_save(const void * ip,const struct xt_entry_match * match)99 static void realm_save(const void *ip, const struct xt_entry_match *match)
100 {
101 const struct xt_realm_info *ri = (const void *)match->data;
102
103 if (ri->invert)
104 printf(" !");
105
106 printf(" --realm");
107 print_realm(ri->id, ri->mask, 0);
108 }
109
110 static struct xtables_match realm_mt_reg = {
111 .name = "realm",
112 .version = XTABLES_VERSION,
113 .family = NFPROTO_IPV4,
114 .size = XT_ALIGN(sizeof(struct xt_realm_info)),
115 .userspacesize = XT_ALIGN(sizeof(struct xt_realm_info)),
116 .help = realm_help,
117 .init = realm_init,
118 .print = realm_print,
119 .save = realm_save,
120 .x6_parse = realm_parse,
121 .x6_options = realm_opts,
122 };
123
_init(void)124 void _init(void)
125 {
126 xtables_register_match(&realm_mt_reg);
127 }
128