udpin.c

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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: udpin.c,v $
00096  * Revision 1.8  2008/08/20 06:57:00  haraldkipp
00097  * Implemented IP demultiplexer.
00098  *
00099  * Revision 1.7  2008/04/18 13:13:11  haraldkipp
00100  * Using fast ints.
00101  *
00102  * Revision 1.6  2006/10/08 16:48:22  haraldkipp
00103  * Documentation fixed
00104  *
00105  * Revision 1.5  2005/06/05 16:48:32  haraldkipp
00106  * Additional parameter enables NutUdpInput() to avoid responding to UDP
00107  * broadcasts with ICMP unreachable messages. Fixes bug #1215192.
00108  *
00109  * Revision 1.4  2005/05/26 11:47:24  drsung
00110  * ICMP unreachable will be sent on incoming udp packets with no local peer port.
00111  *
00112  * Revision 1.3  2005/02/02 16:22:35  haraldkipp
00113  * Do not wake up waiting threads if the incoming datagram
00114  * doesn't fit in the buffer.
00115  *
00116  * Revision 1.2  2003/11/24 21:01:04  drsung
00117  * Packet queue added for UDP sockets.
00118  *
00119  * Revision 1.1.1.1  2003/05/09 14:41:45  haraldkipp
00120  * Initial using 3.2.1
00121  *
00122  * Revision 1.10  2003/02/04 18:14:57  harald
00123  * Version 3 released
00124  *
00125  * Revision 1.9  2002/06/26 17:29:36  harald
00126  * First pre-release with 2.4 stack
00127  *
00128  */
00129 
00130 #include <sys/event.h>
00131 
00132 #include <netinet/udp.h>
00133 #include <sys/socket.h>
00134 #include <netinet/ip_icmp.h>
00135 #include <netinet/icmp.h>
00136 
00141 
00151 int NutUdpInput(NUTDEVICE * dev, NETBUF * nb)
00152 {
00153     UDPHDR *uh;
00154     UDPSOCKET *sock;
00155 
00156     uh = (UDPHDR *) nb->nb_tp.vp;
00157 
00158     nb->nb_ap.vp = uh + 1;
00159     nb->nb_ap.sz = nb->nb_tp.sz - sizeof(UDPHDR);
00160     nb->nb_tp.sz = sizeof(UDPHDR);
00161 
00162     /*
00163      * Find a port. If none exists and if this datagram hasn't been
00164      * broadcasted, return an ICMP unreachable.
00165      */
00166     if ((sock = NutUdpFindSocket(uh->uh_dport)) == 0) {
00167         if ((nb->nb_flags | NBAF_UNICAST) == 0 || 
00168             NutIcmpResponse(ICMP_UNREACH, ICMP_UNREACH_PORT, 0, nb) == 0) {
00169             NutNetBufFree(nb);
00170         }
00171         return 0;
00172     }
00173 
00174     /* if buffer size is defined, use packet queue */
00175     if (sock->so_rx_bsz) {
00176         /* New packet fits into the buffer? */
00177         if (sock->so_rx_cnt + nb->nb_ap.sz > sock->so_rx_bsz) {
00178             /* No, so discard it */
00179             NutNetBufFree(nb);
00180             return 0;
00181         } else {
00182             /* if a first packet is already in the queue, find the end
00183              * and add the new packet */
00184             if (sock->so_rx_nb) {
00185                 NETBUF *snb;
00186                 for (snb = sock->so_rx_nb; snb->nb_next != 0; snb = snb->nb_next);
00187                 snb->nb_next = nb;
00188             } else
00189                 sock->so_rx_nb = nb;
00190 
00191             /* increment input buffer count */
00192             sock->so_rx_cnt += nb->nb_ap.sz;
00193         };
00194     } else {                    /* no packet queue */
00195         /* if a packet is still buffered, discard it */
00196         if (sock->so_rx_nb) {
00197             NutNetBufFree(sock->so_rx_nb);
00198         }
00199         sock->so_rx_nb = nb;
00200         sock->so_rx_cnt = nb->nb_ap.sz; /* set input buffer count to size of new packet */
00201     };
00202 
00203     /* post the event only, if one thread is waiting */
00204     if (sock->so_rx_rdy)
00205         NutEventPost(&sock->so_rx_rdy);
00206     return 0;
00207 }
00208 

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