192680Sdarrenr/*
292680Sdarrenr * Simple netbios-dgm transparent proxy for in-kernel use.
392680Sdarrenr * For use with the NAT code.
4153872Sguido * $Id: ip_netbios_pxy.c,v 2.8.2.1 2005/08/20 13:48:23 darrenr Exp $
592680Sdarrenr */
692680Sdarrenr
792680Sdarrenr/*-
8145516Sdarrenr * Copyright (c) 2002-2003 Paul J. Ledbetter III
992680Sdarrenr * All rights reserved.
1092680Sdarrenr *
1192680Sdarrenr * Redistribution and use in source and binary forms, with or without
1292680Sdarrenr * modification, are permitted provided that the following conditions
1392680Sdarrenr * are met:
1492680Sdarrenr * 1. Redistributions of source code must retain the above copyright
1592680Sdarrenr *    notice, this list of conditions and the following disclaimer.
1692680Sdarrenr * 2. Redistributions in binary form must reproduce the above copyright
1792680Sdarrenr *    notice, this list of conditions and the following disclaimer in the
1892680Sdarrenr *    documentation and/or other materials provided with the distribution.
1992680Sdarrenr *
2092680Sdarrenr * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
2192680Sdarrenr * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
2292680Sdarrenr * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
2392680Sdarrenr * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
2492680Sdarrenr * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
2592680Sdarrenr * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
2692680Sdarrenr * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
2792680Sdarrenr * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
2892680Sdarrenr * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
2992680Sdarrenr * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
3092680Sdarrenr * SUCH DAMAGE.
3192680Sdarrenr *
32153872Sguido * $Id: ip_netbios_pxy.c,v 2.8.2.1 2005/08/20 13:48:23 darrenr Exp $
3392680Sdarrenr */
3492680Sdarrenr
3592680Sdarrenr#define	IPF_NETBIOS_PROXY
3692680Sdarrenr
3792680Sdarrenrint ippr_netbios_init __P((void));
38145516Sdarrenrvoid ippr_netbios_fini __P((void));
39145516Sdarrenrint ippr_netbios_out __P((fr_info_t *, ap_session_t *, nat_t *));
4092680Sdarrenr
4192680Sdarrenrstatic	frentry_t	netbiosfr;
4292680Sdarrenr
43145516Sdarrenrint	netbios_proxy_init = 0;
44145516Sdarrenr
4592680Sdarrenr/*
4692680Sdarrenr * Initialize local structures.
4792680Sdarrenr */
4892680Sdarrenrint ippr_netbios_init()
4992680Sdarrenr{
5092680Sdarrenr	bzero((char *)&netbiosfr, sizeof(netbiosfr));
5192680Sdarrenr	netbiosfr.fr_ref = 1;
5292680Sdarrenr	netbiosfr.fr_flags = FR_INQUE|FR_PASS|FR_QUICK|FR_KEEPSTATE;
53145516Sdarrenr	MUTEX_INIT(&netbiosfr.fr_lock, "NETBIOS proxy rule lock");
54145516Sdarrenr	netbios_proxy_init = 1;
55145516Sdarrenr
5692680Sdarrenr	return 0;
5792680Sdarrenr}
5892680Sdarrenr
59145516Sdarrenr
60145516Sdarrenrvoid ippr_netbios_fini()
61145516Sdarrenr{
62145516Sdarrenr	if (netbios_proxy_init == 1) {
63145516Sdarrenr		MUTEX_DESTROY(&netbiosfr.fr_lock);
64145516Sdarrenr		netbios_proxy_init = 0;
65145516Sdarrenr	}
66145516Sdarrenr}
67145516Sdarrenr
68145516Sdarrenr
69145516Sdarrenrint ippr_netbios_out(fin, aps, nat)
7092680Sdarrenrfr_info_t *fin;
7192680Sdarrenrap_session_t *aps;
7292680Sdarrenrnat_t *nat;
7392680Sdarrenr{
7492680Sdarrenr	char dgmbuf[6];
7592680Sdarrenr	int off, dlen;
7692680Sdarrenr	udphdr_t *udp;
77145516Sdarrenr	ip_t *ip;
7892680Sdarrenr	mb_t *m;
7992680Sdarrenr
80145516Sdarrenr	aps = aps;	/* LINT */
81145516Sdarrenr	nat = nat;	/* LINT */
82145516Sdarrenr
83153872Sguido	m = fin->fin_m;
84153872Sguido	dlen = fin->fin_dlen - sizeof(*udp);
8592680Sdarrenr	/*
8692680Sdarrenr	 * no net bios datagram could possibly be shorter than this
8792680Sdarrenr	 */
88145516Sdarrenr	if (dlen < 11)
8992680Sdarrenr		return 0;
9092680Sdarrenr
91153872Sguido	ip = fin->fin_ip;
9292680Sdarrenr	udp = (udphdr_t *)fin->fin_dp;
93153872Sguido	off = (char *)udp - (char *)ip + sizeof(*udp) + fin->fin_ipoff;
9492680Sdarrenr
95145516Sdarrenr	/*
9692680Sdarrenr	 * move past the
9792680Sdarrenr	 *	ip header;
9892680Sdarrenr	 *	udp header;
99145516Sdarrenr	 *	4 bytes into the net bios dgm header.
10092680Sdarrenr	 *  According to rfc1002, this should be the exact location of
10192680Sdarrenr	 *  the source address/port
10292680Sdarrenr	 */
10392680Sdarrenr	off += 4;
10492680Sdarrenr
10592680Sdarrenr	/* Copy NATed source Address/port*/
10692680Sdarrenr	dgmbuf[0] = (char)((ip->ip_src.s_addr     ) &0xFF);
10792680Sdarrenr	dgmbuf[1] = (char)((ip->ip_src.s_addr >> 8) &0xFF);
10892680Sdarrenr	dgmbuf[2] = (char)((ip->ip_src.s_addr >> 16)&0xFF);
10992680Sdarrenr	dgmbuf[3] = (char)((ip->ip_src.s_addr >> 24)&0xFF);
11092680Sdarrenr
11192680Sdarrenr	dgmbuf[4] = (char)((udp->uh_sport     )&0xFF);
11292680Sdarrenr	dgmbuf[5] = (char)((udp->uh_sport >> 8)&0xFF);
11392680Sdarrenr
11492680Sdarrenr	/* replace data in packet */
115145516Sdarrenr	COPYBACK(m, off, sizeof(dgmbuf), dgmbuf);
11692680Sdarrenr
11792680Sdarrenr	return 0;
11892680Sdarrenr}
119