00001 /* 00002 * Copyright (C) 2001-2003 by egnite Software GmbH. All rights reserved. 00003 * 00004 * Redistribution and use in source and binary forms, with or without 00005 * modification, are permitted provided that the following conditions 00006 * are met: 00007 * 00008 * 1. Redistributions of source code must retain the above copyright 00009 * notice, this list of conditions and the following disclaimer. 00010 * 2. Redistributions in binary form must reproduce the above copyright 00011 * notice, this list of conditions and the following disclaimer in the 00012 * documentation and/or other materials provided with the distribution. 00013 * 3. Neither the name of the copyright holders nor the names of 00014 * contributors may be used to endorse or promote products derived 00015 * from this software without specific prior written permission. 00016 * 00017 * THIS SOFTWARE IS PROVIDED BY EGNITE SOFTWARE GMBH AND CONTRIBUTORS 00018 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 00019 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 00020 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL EGNITE 00021 * SOFTWARE GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 00022 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 00023 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 00024 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 00025 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 00026 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 00027 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 00028 * SUCH DAMAGE. 00029 * 00030 * For additional information see http://www.ethernut.de/ 00031 * 00032 * - 00033 * Portions Copyright (C) 2000 David J. Hudson <dave@humbug.demon.co.uk> 00034 * 00035 * This file is distributed in the hope that it will be useful, but WITHOUT 00036 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 00037 * FITNESS FOR A PARTICULAR PURPOSE. 00038 * 00039 * You can redistribute this file and/or modify it under the terms of the GNU 00040 * General Public License (GPL) as published by the Free Software Foundation; 00041 * either version 2 of the License, or (at your discretion) any later version. 00042 * See the accompanying file "copying-gpl.txt" for more details. 00043 * 00044 * As a special exception to the GPL, permission is granted for additional 00045 * uses of the text contained in this file. See the accompanying file 00046 * "copying-liquorice.txt" for details. 00047 * - 00048 * Portions Copyright (c) 1983, 1993 by 00049 * The Regents of the University of California. All rights reserved. 00050 * 00051 * Redistribution and use in source and binary forms, with or without 00052 * modification, are permitted provided that the following conditions 00053 * are met: 00054 * 1. Redistributions of source code must retain the above copyright 00055 * notice, this list of conditions and the following disclaimer. 00056 * 2. Redistributions in binary form must reproduce the above copyright 00057 * notice, this list of conditions and the following disclaimer in the 00058 * documentation and/or other materials provided with the distribution. 00059 * 3. Neither the name of the University nor the names of its contributors 00060 * may be used to endorse or promote products derived from this software 00061 * without specific prior written permission. 00062 * 00063 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 00064 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 00065 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 00066 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 00067 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 00068 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 00069 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 00070 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 00071 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 00072 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 00073 * SUCH DAMAGE. 00074 * - 00075 * Portions Copyright (c) 1993 by Digital Equipment Corporation. 00076 * 00077 * Permission to use, copy, modify, and distribute this software for any 00078 * purpose with or without fee is hereby granted, provided that the above 00079 * copyright notice and this permission notice appear in all copies, and that 00080 * the name of Digital Equipment Corporation not be used in advertising or 00081 * publicity pertaining to distribution of the document or software without 00082 * specific, written prior permission. 00083 * 00084 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL 00085 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES 00086 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT 00087 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 00088 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 00089 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 00090 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 00091 * SOFTWARE. 00092 */ 00093 00094 /* 00095 * $Log: arpin.c,v $ 00096 * Revision 1.3 2005/04/08 15:20:50 olereinhardt 00097 * added <sys/types.h> (__APPLE__) and <netinet/in.h> (__linux__) 00098 * for htons and simmilar. 00099 * 00100 * Revision 1.2 2004/07/27 19:41:00 drsung 00101 * If NutArpOutput fails, the NetBuf must not be deallocated by 00102 * calling NutNetBufFree. 00103 * 00104 * Revision 1.1.1.1 2003/05/09 14:41:26 haraldkipp 00105 * Initial using 3.2.1 00106 * 00107 * Revision 1.9 2003/02/04 18:14:56 harald 00108 * Version 3 released 00109 * 00110 * Revision 1.8 2002/06/26 17:29:35 harald 00111 * First pre-release with 2.4 stack 00112 * 00113 */ 00114 #include <sys/types.h> 00115 #include <net/if_var.h> 00116 #include <netinet/if_ether.h> 00117 #include <netinet/in.h> 00124 00125 00140 void NutArpInput(NUTDEVICE * dev, NETBUF * nb) 00141 { 00142 ETHERARP *ea; 00143 ARPHDR *ah; 00144 IFNET *nif; 00145 00146 ea = (ETHERARP *) nb->nb_nw.vp; 00147 ah = (ARPHDR *) & ea->ea_hdr; 00148 00149 /* 00150 * Silently discard packets with unsupported 00151 * address types and lengths. 00152 */ 00153 if (ntohs(ah->ar_hrd) != ARPHRD_ETHER || 00154 ntohs(ah->ar_pro) != ETHERTYPE_IP || 00155 ah->ar_hln != 6 || ah->ar_pln != 4) { 00156 NutNetBufFree(nb); 00157 return; 00158 } 00159 00160 /* 00161 * Silently discard packets for other destinations. 00162 */ 00163 nif = dev->dev_icb; 00164 if (ea->arp_tpa != nif->if_local_ip) { 00165 NutNetBufFree(nb); 00166 return; 00167 } 00168 00169 /* 00170 * TODO: Silently discard packets with our own 00171 * source address. 00172 */ 00173 00174 /* 00175 * TODO: Discard packets with broadcast source 00176 * address. 00177 */ 00178 00179 /* 00180 * TODO: Discard packets if source IP address 00181 * equals our address. We should send a reply. 00182 */ 00183 00184 /* 00185 * Add the sender to our arp cache. Note, that we don't do 00186 * this with replies only, but also with requests on our 00187 * address. The assumption is that if someone is requesting 00188 * our address, they are probably intending to talk to us, 00189 * so it saves time if we cache their address. 00190 */ 00191 NutArpCacheUpdate(dev, ea->arp_spa, ea->arp_sha); 00192 00193 /* 00194 * Reply to ARP requests. 00195 */ 00196 if (htons(ea->ea_hdr.ar_op) == ARPOP_REQUEST) { 00197 NETBUF *nbr = 00198 NutArpAllocNetBuf(ARPOP_REPLY, ea->arp_spa, ea->arp_sha); 00199 00200 if (nbr) { 00201 if (!NutArpOutput(dev, nbr)) 00202 NutNetBufFree(nbr); 00203 } 00204 } 00205 NutNetBufFree(nb); 00206 } 00207