1 /* 802_3
2 *
3 * Author:
4 * Chris Vitale <[email protected]>
5 *
6 * May 2003
7 *
8 * Adapted by Arturo Borrero Gonzalez <[email protected]>
9 * to use libxtables for ebtables-compat
10 */
11
12 #include <stdbool.h>
13 #include <stdio.h>
14 #include <string.h>
15 #include <stdlib.h>
16 #include <getopt.h>
17 #include <xtables.h>
18 #include <linux/netfilter_bridge/ebt_802_3.h>
19
20 #define _802_3_SAP '1'
21 #define _802_3_TYPE '2'
22
23 static const struct option br802_3_opts[] = {
24 { .name = "802_3-sap", .has_arg = true, .val = _802_3_SAP },
25 { .name = "802_3-type", .has_arg = true, .val = _802_3_TYPE },
26 XT_GETOPT_TABLEEND,
27 };
28
br802_3_print_help(void)29 static void br802_3_print_help(void)
30 {
31 printf(
32 "802_3 options:\n"
33 "--802_3-sap [!] protocol : 802.3 DSAP/SSAP- 1 byte value (hex)\n"
34 " DSAP and SSAP are always the same. One SAP applies to both fields\n"
35 "--802_3-type [!] protocol : 802.3 SNAP Type- 2 byte value (hex)\n"
36 " Type implies SAP value 0xaa\n");
37 }
38
br802_3_init(struct xt_entry_match * match)39 static void br802_3_init(struct xt_entry_match *match)
40 {
41 struct ebt_802_3_info *info = (struct ebt_802_3_info *)match->data;
42
43 info->invflags = 0;
44 info->bitmask = 0;
45 }
46
47 static int
br802_3_parse(int c,char ** argv,int invert,unsigned int * flags,const void * entry,struct xt_entry_match ** match)48 br802_3_parse(int c, char **argv, int invert, unsigned int *flags,
49 const void *entry, struct xt_entry_match **match)
50 {
51 struct ebt_802_3_info *info = (struct ebt_802_3_info *) (*match)->data;
52 unsigned int i;
53 char *end;
54
55 switch (c) {
56 case _802_3_SAP:
57 if (invert)
58 info->invflags |= EBT_802_3_SAP;
59 i = strtoul(optarg, &end, 16);
60 if (i > 255 || *end != '\0')
61 xtables_error(PARAMETER_PROBLEM,
62 "Problem with specified "
63 "sap hex value, %x",i);
64 info->sap = i; /* one byte, so no byte order worries */
65 info->bitmask |= EBT_802_3_SAP;
66 break;
67 case _802_3_TYPE:
68 if (invert)
69 info->invflags |= EBT_802_3_TYPE;
70 i = strtoul(optarg, &end, 16);
71 if (i > 65535 || *end != '\0') {
72 xtables_error(PARAMETER_PROBLEM,
73 "Problem with the specified "
74 "type hex value, %x",i);
75 }
76 info->type = htons(i);
77 info->bitmask |= EBT_802_3_TYPE;
78 break;
79 default:
80 return 0;
81 }
82
83 *flags |= info->bitmask;
84 return 1;
85 }
86
87 static void
br802_3_final_check(unsigned int flags)88 br802_3_final_check(unsigned int flags)
89 {
90 if (!flags)
91 xtables_error(PARAMETER_PROBLEM,
92 "You must specify proper arguments");
93 }
94
br802_3_print(const void * ip,const struct xt_entry_match * match,int numeric)95 static void br802_3_print(const void *ip, const struct xt_entry_match *match,
96 int numeric)
97 {
98 struct ebt_802_3_info *info = (struct ebt_802_3_info *)match->data;
99
100 if (info->bitmask & EBT_802_3_SAP) {
101 printf("--802_3-sap ");
102 if (info->invflags & EBT_802_3_SAP)
103 printf("! ");
104 printf("0x%.2x ", info->sap);
105 }
106 if (info->bitmask & EBT_802_3_TYPE) {
107 printf("--802_3-type ");
108 if (info->invflags & EBT_802_3_TYPE)
109 printf("! ");
110 printf("0x%.4x ", ntohs(info->type));
111 }
112 }
113
114 static struct xtables_match br802_3_match =
115 {
116 .name = "802_3",
117 .revision = 0,
118 .version = XTABLES_VERSION,
119 .family = NFPROTO_BRIDGE,
120 .size = XT_ALIGN(sizeof(struct ebt_802_3_info)),
121 .userspacesize = XT_ALIGN(sizeof(struct ebt_802_3_info)),
122 .init = br802_3_init,
123 .help = br802_3_print_help,
124 .parse = br802_3_parse,
125 .final_check = br802_3_final_check,
126 .print = br802_3_print,
127 .extra_opts = br802_3_opts,
128 };
129
_init(void)130 void _init(void)
131 {
132 xtables_register_match(&br802_3_match);
133 }
134