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/*
* (C) 2005-2007 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/libnetfilter_conntrack.h>
#include <libnetfilter_conntrack/libnetfilter_conntrack_udp.h>
#include "conntrack.h"
static struct option opts[] = {
{"orig-port-src", 1, 0, '1'},
{"sport", 1, 0, '1'},
{"orig-port-dst", 1, 0, '2'},
{"dport", 1, 0, '2'},
{"reply-port-src", 1, 0, '3'},
{"reply-port-dst", 1, 0, '4'},
{"mask-port-src", 1, 0, '5'},
{"mask-port-dst", 1, 0, '6'},
{"tuple-port-src", 1, 0, '7'},
{"tuple-port-dst", 1, 0, '8'},
{0, 0, 0, 0}
};
static void help()
{
fprintf(stdout, " --orig-port-src\t\toriginal source port\n");
fprintf(stdout, " --orig-port-dst\t\toriginal destination port\n");
fprintf(stdout, " --reply-port-src\t\treply source port\n");
fprintf(stdout, " --reply-port-dst\t\treply destination port\n");
fprintf(stdout, " --mask-port-src\t\tmask source port\n");
fprintf(stdout, " --mask-port-dst\t\tmask destination port\n");
fprintf(stdout, " --tuple-port-src\t\texpectation tuple src port\n");
fprintf(stdout, " --tuple-port-src\t\texpectation tuple dst port\n");
}
static int parse_options(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_u16(ct,
ATTR_ORIG_PORT_SRC,
htons(atoi(optarg)));
*flags |= UDP_ORIG_SPORT;
break;
case '2':
if (!optarg)
break;
nfct_set_attr_u16(ct,
ATTR_ORIG_PORT_DST,
htons(atoi(optarg)));
*flags |= UDP_ORIG_DPORT;
break;
case '3':
if (!optarg)
break;
nfct_set_attr_u16(ct,
ATTR_REPL_PORT_SRC,
htons(atoi(optarg)));
*flags |= UDP_REPL_SPORT;
break;
case '4':
if (!optarg)
break;
nfct_set_attr_u16(ct,
ATTR_REPL_PORT_DST,
htons(atoi(optarg)));
*flags |= UDP_REPL_DPORT;
break;
case '5':
if (!optarg)
break;
nfct_set_attr_u16(mask,
ATTR_ORIG_PORT_SRC,
htons(atoi(optarg)));
*flags |= UDP_MASK_SPORT;
break;
case '6':
if (!optarg)
break;
nfct_set_attr_u16(mask,
ATTR_ORIG_PORT_DST,
htons(atoi(optarg)));
*flags |= UDP_MASK_DPORT;
break;
case '7':
if (!optarg)
break;
nfct_set_attr_u16(exptuple,
ATTR_ORIG_PORT_SRC,
htons(atoi(optarg)));
*flags |= UDP_EXPTUPLE_SPORT;
break;
case '8':
if (!optarg)
break;
nfct_set_attr_u16(exptuple,
ATTR_ORIG_PORT_DST,
htons(atoi(optarg)));
*flags |= UDP_EXPTUPLE_DPORT;
break;
}
return 1;
}
static int final_check(unsigned int flags,
unsigned int command,
struct nf_conntrack *ct)
{
int ret = 0;
if ((flags & (UDP_ORIG_SPORT|UDP_ORIG_DPORT))
&& !(flags & (UDP_REPL_SPORT|UDP_REPL_DPORT))) {
nfct_set_attr_u16(ct,
ATTR_REPL_PORT_SRC,
nfct_get_attr_u16(ct, ATTR_ORIG_PORT_DST));
nfct_set_attr_u16(ct,
ATTR_REPL_PORT_DST,
nfct_get_attr_u16(ct, ATTR_ORIG_PORT_SRC));
ret = 1;
} else if (!(flags & (UDP_ORIG_SPORT|UDP_ORIG_DPORT))
&& (flags & (UDP_REPL_SPORT|UDP_REPL_DPORT))) {
nfct_set_attr_u16(ct,
ATTR_ORIG_PORT_SRC,
nfct_get_attr_u16(ct, ATTR_REPL_PORT_DST));
nfct_set_attr_u16(ct,
ATTR_ORIG_PORT_DST,
nfct_get_attr_u16(ct, ATTR_REPL_PORT_SRC));
ret = 1;
}
if ((flags & (UDP_ORIG_SPORT|UDP_ORIG_DPORT))
&& ((flags & (UDP_REPL_SPORT|UDP_REPL_DPORT))))
ret = 1;
return ret;
}
static struct ctproto_handler udp = {
.name = "udp",
.protonum = IPPROTO_UDP,
.parse_opts = parse_options,
.final_check = final_check,
.help = help,
.opts = opts,
.version = VERSION,
};
static void __attribute__ ((constructor)) init(void);
static void init(void)
{
register_proto(&udp);
}
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