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/*
* (C) 2005-2007 by Pablo Neira Ayuso <pablo@netfilter.org>
* 2005 by Harald Welte <laforge@netfilter.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
*/
#include <stdio.h>
#include <getopt.h>
#include <stdlib.h>
#include <netinet/in.h> /* For htons */
#include <netinet/ip_icmp.h>
#include <libnetfilter_conntrack/libnetfilter_conntrack.h>
#include <libnetfilter_conntrack/libnetfilter_conntrack_icmp.h>
#include "conntrack.h"
static struct option opts[] = {
{"icmp-type", 1, 0, '1'},
{"icmp-code", 1, 0, '2'},
{"icmp-id", 1, 0, '3'},
{0, 0, 0, 0}
};
static void help()
{
fprintf(stdout, " --icmp-type\t\t\ticmp type\n");
fprintf(stdout, " --icmp-code\t\t\ticmp code\n");
fprintf(stdout, " --icmp-id\t\t\ticmp id\n");
}
static int parse(char c, char *argv[],
struct nf_conntrack *ct,
struct nf_conntrack *exptuple,
struct nf_conntrack *mask,
unsigned int *flags)
{
switch(c) {
case '1':
if (!optarg)
break;
nfct_set_attr_u8(ct,
ATTR_ICMP_TYPE,
atoi(optarg));
*flags |= ICMP_TYPE;
break;
case '2':
if (!optarg)
break;
nfct_set_attr_u8(ct,
ATTR_ICMP_CODE,
atoi(optarg));
*flags |= ICMP_CODE;
break;
case '3':
if (!optarg)
break;
nfct_set_attr_u16(ct,
ATTR_ICMP_ID,
htons(atoi(optarg)));
*flags |= ICMP_ID;
break;
}
return 1;
}
static int final_check(unsigned int flags,
unsigned int command,
struct nf_conntrack *ct)
{
if (!(flags & ICMP_TYPE))
return 0;
else if (!(flags & ICMP_CODE))
return 0;
return 1;
}
static struct ctproto_handler icmp = {
.name = "icmp",
.protonum = IPPROTO_ICMP,
.parse_opts = parse,
.final_check = final_check,
.help = help,
.opts = opts,
.version = VERSION,
};
static void __attribute__ ((constructor)) init(void);
static void init(void)
{
register_proto(&icmp);
}
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