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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 <arpa/inet.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_l3extensions.h>
#include <libnetfilter_conntrack/libnetfilter_conntrack_ipv4.h>
static void parse_proto(struct nfattr *cda[], struct nfct_tuple *tuple)
{
if (cda[CTA_IP_V4_SRC-1])
tuple->src.v4 = *(u_int32_t *)NFA_DATA(cda[CTA_IP_V4_SRC-1]);
if (cda[CTA_IP_V4_DST-1])
tuple->dst.v4 = *(u_int32_t *)NFA_DATA(cda[CTA_IP_V4_DST-1]);
}
static void build_tuple_proto(struct nfnlhdr *req, int size,
struct nfct_tuple *t)
{
nfnl_addattr_l(&req->nlh, size, CTA_IP_V4_SRC, &t->src.v4,
sizeof(u_int32_t));
nfnl_addattr_l(&req->nlh, size, CTA_IP_V4_DST, &t->dst.v4,
sizeof(u_int32_t));
}
static int print_proto(char *buf, struct nfct_tuple *tuple)
{
struct in_addr src = { .s_addr = tuple->src.v4 };
struct in_addr dst = { .s_addr = tuple->dst.v4 };
int size;
size = sprintf(buf, "src=%s ", inet_ntoa(src));
size += sprintf(buf+size, "dst=%s ", inet_ntoa(dst));
return size;
}
static int compare(struct nfct_conntrack *ct1,
struct nfct_conntrack *ct2,
unsigned int flags)
{
if (flags & IPV4_ORIG)
if (ct1->tuple[NFCT_DIR_ORIGINAL].l3protonum !=
ct2->tuple[NFCT_DIR_ORIGINAL].l3protonum)
return 0;
if (flags & IPV4_REPL)
if (ct1->tuple[NFCT_DIR_REPLY].l3protonum !=
ct2->tuple[NFCT_DIR_REPLY].l3protonum)
return 0;
if (flags & IPV4_ORIG_SRC)
if (ct1->tuple[NFCT_DIR_ORIGINAL].src.v4 !=
ct2->tuple[NFCT_DIR_ORIGINAL].src.v4)
return 0;
if (flags & IPV4_ORIG_DST)
if (ct1->tuple[NFCT_DIR_ORIGINAL].dst.v4 !=
ct2->tuple[NFCT_DIR_ORIGINAL].dst.v4)
return 0;
if (flags & IPV4_REPL_SRC)
if (ct1->tuple[NFCT_DIR_REPLY].src.v4 !=
ct2->tuple[NFCT_DIR_REPLY].src.v4)
return 0;
if (flags & IPV4_REPL_DST)
if (ct1->tuple[NFCT_DIR_REPLY].dst.v4 !=
ct2->tuple[NFCT_DIR_REPLY].dst.v4)
return 0;
return 1;
}
static struct nfct_l3proto ipv4 = {
.name = "ipv4",
.protonum = AF_INET,
.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_l3proto(&ipv4);
}
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