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/* ebt_nat
*
* Authors:
* Bart De Schuymer <bdschuym@pandora.be>
*
* June, 2002
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <getopt.h>
#include <netinet/ether.h>
#include <xtables.h>
#include <linux/netfilter_bridge/ebt_nat.h>
#include "iptables/nft.h"
#include "iptables/nft-bridge.h"
#define NAT_D '1'
#define NAT_D_TARGET '2'
static const struct option brdnat_opts[] =
{
{ "to-destination", required_argument, 0, NAT_D },
{ "to-dst" , required_argument, 0, NAT_D },
{ "dnat-target" , required_argument, 0, NAT_D_TARGET },
{ 0 }
};
static void brdnat_print_help(void)
{
printf(
"dnat options:\n"
" --to-dst address : MAC address to map destination to\n"
" --dnat-target target : ACCEPT, DROP, RETURN or CONTINUE\n");
}
static void brdnat_init(struct xt_entry_target *target)
{
struct ebt_nat_info *natinfo = (struct ebt_nat_info *)target->data;
natinfo->target = EBT_ACCEPT;
}
#define OPT_DNAT 0x01
#define OPT_DNAT_TARGET 0x02
static int brdnat_parse(int c, char **argv, int invert, unsigned int *flags,
const void *entry, struct xt_entry_target **target)
{
struct ebt_nat_info *natinfo = (struct ebt_nat_info *)(*target)->data;
struct ether_addr *addr;
switch (c) {
case NAT_D:
EBT_CHECK_OPTION(flags, OPT_DNAT);
if (!(addr = ether_aton(optarg)))
xtables_error(PARAMETER_PROBLEM, "Problem with specified --to-destination mac");
memcpy(natinfo->mac, addr, ETH_ALEN);
break;
case NAT_D_TARGET:
EBT_CHECK_OPTION(flags, OPT_DNAT_TARGET);
if (ebt_fill_target(optarg, (unsigned int *)&natinfo->target))
xtables_error(PARAMETER_PROBLEM, "Illegal --dnat-target target");
break;
default:
return 0;
}
return 1;
}
static void brdnat_final_check(unsigned int flags)
{
if (!flags)
xtables_error(PARAMETER_PROBLEM,
"You must specify proper arguments");
}
static void brdnat_print(const void *ip, const struct xt_entry_target *target, int numeric)
{
struct ebt_nat_info *natinfo = (struct ebt_nat_info *)target->data;
printf("--to-dst ");
xtables_print_mac(natinfo->mac);
printf(" --dnat-target %s", ebt_target_name(natinfo->target));
}
static const char* brdnat_verdict(int verdict)
{
switch (verdict) {
case EBT_ACCEPT: return "accept";
case EBT_DROP: return "drop";
case EBT_CONTINUE: return "continue";
case EBT_RETURN: return "return";
}
return "";
}
static int brdnat_xlate(struct xt_xlate *xl,
const struct xt_xlate_tg_params *params)
{
const struct ebt_nat_info *natinfo = (const void*)params->target->data;
xt_xlate_add(xl, "ether daddr set %s %s ",
ether_ntoa((struct ether_addr *)natinfo->mac),
brdnat_verdict(natinfo->target));
return 1;
}
static struct xtables_target brdnat_target =
{
.name = "dnat",
.version = XTABLES_VERSION,
.family = NFPROTO_BRIDGE,
.size = XT_ALIGN(sizeof(struct ebt_nat_info)),
.userspacesize = XT_ALIGN(sizeof(struct ebt_nat_info)),
.help = brdnat_print_help,
.init = brdnat_init,
.parse = brdnat_parse,
.final_check = brdnat_final_check,
.print = brdnat_print,
.xlate = brdnat_xlate,
.extra_opts = brdnat_opts,
};
void _init(void)
{
xtables_register_target(&brdnat_target);
}
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