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/*
* (C) 2005 by Pablo Neira Ayuso <pablo@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 <string.h>
#include <netinet/in.h> /* For htons */
#include <libnetfilter_conntrack/linux_nfnetlink_conntrack.h>
#include <libnetfilter_conntrack/libnetfilter_conntrack.h>
#include <libnetfilter_conntrack/libnetfilter_conntrack_extensions.h>
#include <libnetfilter_conntrack/libnetfilter_conntrack_icmp.h>
static void parse_proto(struct nfattr *cda[], struct nfct_tuple *tuple)
{
if (cda[CTA_PROTO_ICMP_TYPE-1])
tuple->l4dst.icmp.type =
*(u_int8_t *)NFA_DATA(cda[CTA_PROTO_ICMP_TYPE-1]);
if (cda[CTA_PROTO_ICMP_CODE-1])
tuple->l4dst.icmp.code =
*(u_int8_t *)NFA_DATA(cda[CTA_PROTO_ICMP_CODE-1]);
if (cda[CTA_PROTO_ICMP_ID-1])
tuple->l4src.icmp.id =
*(u_int16_t *)NFA_DATA(cda[CTA_PROTO_ICMP_ID-1]);
}
static void build_tuple_proto(struct nfnlhdr *req, int size,
struct nfct_tuple *t)
{
nfnl_addattr_l(&req->nlh, size, CTA_PROTO_ICMP_CODE,
&t->l4dst.icmp.code, sizeof(u_int8_t));
nfnl_addattr_l(&req->nlh, size, CTA_PROTO_ICMP_TYPE,
&t->l4dst.icmp.type, sizeof(u_int8_t));
nfnl_addattr_l(&req->nlh, size, CTA_PROTO_ICMP_ID,
&t->l4src.icmp.id, sizeof(u_int16_t));
}
static int print_proto(char *buf, struct nfct_tuple *t)
{
/* The ID only makes sense some ICMP messages but we want to
* display the same output that /proc/net/ip_conntrack does */
return (sprintf(buf, "type=%d code=%d id=%d ",t->l4dst.icmp.type,
t->l4dst.icmp.code,
ntohs(t->l4src.icmp.id)));
}
static int compare(struct nfct_conntrack *ct1,
struct nfct_conntrack *ct2,
unsigned int flags)
{
if (flags & ICMP_TYPE)
if (ct1->tuple[NFCT_DIR_ORIGINAL].l4dst.icmp.type !=
ct2->tuple[NFCT_DIR_ORIGINAL].l4dst.icmp.type)
return 0;
if (flags & ICMP_CODE)
if (ct1->tuple[NFCT_DIR_ORIGINAL].l4dst.icmp.code !=
ct2->tuple[NFCT_DIR_ORIGINAL].l4dst.icmp.code)
return 0;
if (flags & ICMP_ID)
if (ct1->tuple[NFCT_DIR_REPLY].l4src.icmp.id !=
ct2->tuple[NFCT_DIR_REPLY].l4src.icmp.id)
return 0;
return 1;
}
static struct nfct_proto icmp = {
.name = "icmp",
.protonum = IPPROTO_ICMP,
.parse_proto = parse_proto,
.build_tuple_proto = build_tuple_proto,
.print_proto = print_proto,
.compare = compare,
.version = VERSION
};
static void __attribute__ ((constructor)) init(void);
static void init(void)
{
nfct_register_proto(&icmp);
}
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