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/* 802_3
*
* Author:
* Chris Vitale <csv@bluetail.com>
*
* May 2003
*/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <getopt.h>
#include "../include/ebtables_u.h"
#include "../include/ethernetdb.h"
#include <linux/netfilter_bridge/ebt_802_3.h>
#define _802_3_SAP '1'
#define _802_3_TYPE '2'
static struct option opts[] =
{
{ "802_3-sap" , required_argument, 0, _802_3_SAP },
{ "802_3-type" , required_argument, 0, _802_3_TYPE },
{ 0 }
};
static void print_help()
{
printf(
"802_3 options:\n"
"--802_3-sap [!] protocol : 802.3 DSAP/SSAP- 1 byte value (hex)\n"
" DSAP and SSAP are always the same. One SAP applies to both fields\n"
"--802_3-type [!] protocol : 802.3 SNAP Type- 2 byte value (hex)\n"
" Type implies SAP value 0xaa\n");
}
static void init(struct ebt_entry_match *match)
{
struct ebt_802_3_info *info = (struct ebt_802_3_info *)match->data;
info->invflags = 0;
info->bitmask = 0;
}
static int parse(int c, char **argv, int argc, const struct ebt_u_entry *entry,
unsigned int *flags, struct ebt_entry_match **match)
{
struct ebt_802_3_info *info = (struct ebt_802_3_info *) (*match)->data;
unsigned int i;
char *end;
switch (c) {
case _802_3_SAP:
ebt_check_option2(flags, _802_3_SAP);
if (ebt_check_inverse2(optarg))
info->invflags |= EBT_802_3_SAP;
i = strtoul(optarg, &end, 16);
if (i > 255 || *end != '\0')
ebt_print_error2("Problem with specified "
"sap hex value, %x",i);
info->sap = i; /* one byte, so no byte order worries */
info->bitmask |= EBT_802_3_SAP;
break;
case _802_3_TYPE:
ebt_check_option2(flags, _802_3_TYPE);
if (ebt_check_inverse2(optarg))
info->invflags |= EBT_802_3_TYPE;
i = strtoul(optarg, &end, 16);
if (i > 65535 || *end != '\0') {
ebt_print_error2("Problem with the specified "
"type hex value, %x",i);
}
info->type = htons(i);
info->bitmask |= EBT_802_3_TYPE;
break;
default:
return 0;
}
return 1;
}
static void final_check(const struct ebt_u_entry *entry,
const struct ebt_entry_match *match, const char *name,
unsigned int hookmask, unsigned int time)
{
if (!(entry->bitmask & EBT_802_3))
ebt_print_error("For 802.3 DSAP/SSAP filtering the protocol "
"must be LENGTH");
}
static void print(const struct ebt_u_entry *entry,
const struct ebt_entry_match *match)
{
struct ebt_802_3_info *info = (struct ebt_802_3_info *)match->data;
if (info->bitmask & EBT_802_3_SAP) {
printf("--802_3-sap ");
if (info->invflags & EBT_802_3_SAP)
printf("! ");
printf("0x%.2x ", info->sap);
}
if (info->bitmask & EBT_802_3_TYPE) {
printf("--802_3-type ");
if (info->invflags & EBT_802_3_TYPE)
printf("! ");
printf("0x%.4x ", ntohs(info->type));
}
}
static int compare(const struct ebt_entry_match *m1,
const struct ebt_entry_match *m2)
{
struct ebt_802_3_info *info1 = (struct ebt_802_3_info *)m1->data;
struct ebt_802_3_info *info2 = (struct ebt_802_3_info *)m2->data;
if (info1->bitmask != info2->bitmask)
return 0;
if (info1->invflags != info2->invflags)
return 0;
if (info1->bitmask & EBT_802_3_SAP) {
if (info1->sap != info2->sap)
return 0;
}
if (info1->bitmask & EBT_802_3_TYPE) {
if (info1->type != info2->type)
return 0;
}
return 1;
}
static struct ebt_u_match _802_3_match =
{
.name = "802_3",
.size = sizeof(struct ebt_802_3_info),
.help = print_help,
.init = init,
.parse = parse,
.final_check = final_check,
.print = print,
.compare = compare,
.extra_ops = opts,
};
void _init(void)
{
ebt_register_match(&_802_3_match);
}
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