1/* $NetBSD: ip_netbios_pxy.c,v 1.4 2007/12/11 04:55:02 lukem Exp $ */ 2 3/* 4 * Simple netbios-dgm transparent proxy for in-kernel use. 5 * For use with the NAT code. 6 * Id: ip_netbios_pxy.c,v 2.8.2.1 2005/08/20 13:48:23 darrenr Exp 7 */ 8 9/*- 10 * Copyright (c) 2002-2003 Paul J. Ledbetter III 11 * All rights reserved. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * Id: ip_netbios_pxy.c,v 2.8.2.1 2005/08/20 13:48:23 darrenr Exp 35 */ 36 37#include <sys/cdefs.h> 38__KERNEL_RCSID(1, "$NetBSD: ip_netbios_pxy.c,v 1.4 2007/12/11 04:55:02 lukem Exp $"); 39 40#define IPF_NETBIOS_PROXY 41 42int 43ippr_netbios_init(void); 44void 45ippr_netbios_fini(void); 46int 47ippr_netbios_out(fr_info_t *, ap_session_t *, nat_t *); 48 49static frentry_t netbiosfr; 50 51int netbios_proxy_init = 0; 52 53/* 54 * Initialize local structures. 55 */ 56int 57ippr_netbios_init(void) 58{ 59 bzero((char *)&netbiosfr, sizeof(netbiosfr)); 60 netbiosfr.fr_ref = 1; 61 netbiosfr.fr_flags = FR_INQUE|FR_PASS|FR_QUICK|FR_KEEPSTATE; 62 MUTEX_INIT(&netbiosfr.fr_lock, "NETBIOS proxy rule lock"); 63 netbios_proxy_init = 1; 64 65 return 0; 66} 67 68 69void 70ippr_netbios_fini(void) 71{ 72 if (netbios_proxy_init == 1) { 73 MUTEX_DESTROY(&netbiosfr.fr_lock); 74 netbios_proxy_init = 0; 75 } 76} 77 78 79int 80ippr_netbios_out(fr_info_t *fin, ap_session_t *aps, nat_t *nat) 81{ 82 char dgmbuf[6]; 83 int off, dlen; 84 udphdr_t *udp; 85 ip_t *ip; 86 mb_t *m; 87 88 aps = aps; /* LINT */ 89 nat = nat; /* LINT */ 90 91 m = fin->fin_m; 92 dlen = fin->fin_dlen - sizeof(*udp); 93 /* 94 * no net bios datagram could possibly be shorter than this 95 */ 96 if (dlen < 11) 97 return 0; 98 99 ip = fin->fin_ip; 100 udp = (udphdr_t *)fin->fin_dp; 101 off = (char *)udp - (char *)ip + sizeof(*udp) + fin->fin_ipoff; 102 103 /* 104 * move past the 105 * ip header; 106 * udp header; 107 * 4 bytes into the net bios dgm header. 108 * According to rfc1002, this should be the exact location of 109 * the source address/port 110 */ 111 off += 4; 112 113 /* Copy NATed source Address/port*/ 114 dgmbuf[0] = (char)((ip->ip_src.s_addr ) &0xFF); 115 dgmbuf[1] = (char)((ip->ip_src.s_addr >> 8) &0xFF); 116 dgmbuf[2] = (char)((ip->ip_src.s_addr >> 16)&0xFF); 117 dgmbuf[3] = (char)((ip->ip_src.s_addr >> 24)&0xFF); 118 119 dgmbuf[4] = (char)((udp->uh_sport )&0xFF); 120 dgmbuf[5] = (char)((udp->uh_sport >> 8)&0xFF); 121 122 /* replace data in packet */ 123 COPYBACK(m, off, sizeof(dgmbuf), dgmbuf); 124 125 return 0; 126} 127