ipout.c

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/*
 * Copyright (C) 2001-2007 by egnite Software GmbH. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the copyright holders nor the names of
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY EGNITE SOFTWARE GMBH AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL EGNITE
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 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
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 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * For additional information see http://www.ethernut.de/
 *
 * -
 * Portions Copyright (C) 2000 David J. Hudson <dave@humbug.demon.co.uk>
 *
 * This file is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.
 *
 * You can redistribute this file and/or modify it under the terms of the GNU
 * General Public License (GPL) as published by the Free Software Foundation;
 * either version 2 of the License, or (at your discretion) any later version.
 * See the accompanying file "copying-gpl.txt" for more details.
 *
 * As a special exception to the GPL, permission is granted for additional
 * uses of the text contained in this file.  See the accompanying file
 * "copying-liquorice.txt" for details.
 * -
 * Portions Copyright (c) 1983, 1993 by
 *  The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * -
 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies, and that
 * the name of Digital Equipment Corporation not be used in advertising or
 * publicity pertaining to distribution of the document or software without
 * specific, written prior permission.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
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 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 * SOFTWARE.
 */

/*
 * $Log$
 * Revision 1.7  2008/08/11 07:00:30  haraldkipp
 * BSD types replaced by stdint types (feature request #1282721).
 *
 * Revision 1.6  2007/05/02 11:18:32  haraldkipp
 * IGMP support added. Incomplete.
 *
 * Revision 1.5  2006/10/17 11:05:03  haraldkipp
 * Failed ARP requests are no longer classified as fatal transmission errors.
 *
 * Revision 1.4  2005/04/08 15:20:50  olereinhardt
 * added <sys/types.h> (__APPLE__) and <netinet/in.h> (__linux__)
 * for htons and simmilar.
 *
 * Revision 1.3  2004/10/10 16:37:03  drsung
 * Detection of directed broadcasts to local network added.
 *
 * Revision 1.2  2003/07/20 16:00:23  haraldkipp
 * Memory hole fixed.
 *
 * Revision 1.1.1.1  2003/05/09 14:41:33  haraldkipp
 * Initial using 3.2.1
 *
 * Revision 1.17  2003/04/01 18:31:47  harald
 * *** empty log message ***
 *
 * Revision 1.16  2003/03/31 12:28:10  harald
 * Check NEBUF allocation
 *
 * Revision 1.15  2003/02/04 18:14:57  harald
 * Version 3 released
 *
 * Revision 1.14  2003/01/14 16:44:08  harald
 * *** empty log message ***
 *
 * Revision 1.13  2002/10/29 15:32:14  harald
 * PPP support
 *
 * Revision 1.12  2002/09/15 16:49:42  harald
 * *** empty log message ***
 *
 * Revision 1.11  2002/06/26 17:29:36  harald
 * First pre-release with 2.4 stack
 *
 */

#include <string.h>

#include <sys/types.h>
#include <net/ether.h>
#include <net/route.h>
#include <netinet/if_ether.h>
#include <netinet/if_ppp.h>
#include <netinet/ipcsum.h>
#include <netinet/ip.h>
#include <netinet/in.h>

int NutIpOutput(uint8_t proto, uint32_t dest, NETBUF * nb)
{
    uint8_t ha[6];
    IPHDR_OPT *ip;
    NUTDEVICE *dev;
    IFNET *nif;
    uint32_t gate;

    if (proto != IPPROTO_IGMP) {
        if ((nb = NutNetBufAlloc(nb, NBAF_NETWORK, sizeof(IPHDR))) == 0)
            return -1;
    } else {
        if ((nb = NutNetBufAlloc(nb, NBAF_NETWORK, sizeof(IPHDR_OPT))) == 0)
            return -1;
    }

    /*
     * Set those items in the IP header, which are common for
     * all interfaces.
     */
    ip = nb->nb_nw.vp;
    ip->ip_v = 4;
    if (proto == IPPROTO_IGMP) {
        ip->ip_hl = sizeof(IPHDR_OPT) / 4;
    } else {
        ip->ip_hl = sizeof(IPHDR) / 4;
    }
    ip->ip_tos = 0;
    ip->ip_len = htons(nb->nb_nw.sz + nb->nb_tp.sz + nb->nb_ap.sz);
    ip->ip_off = 0;
    if (proto == IPPROTO_IGMP) {
        ip->ip_ttl = 1;
    } else {
        ip->ip_ttl = 0x40;
    }
    ip->ip_p = proto;
    ip->ip_dst = dest;

    if (proto == IPPROTO_IGMP) {
        /* Router Alert Option */
        ip->ip_option = htonl(0x94040000);
    }


    /*
     * Limited broadcasts are sent on all network interfaces.
     * See RFC 919.
     */
    if ((dest == 0xffffffff) || (IP_IS_MULTICAST(dest))) {
        if (dest == 0xffffffff) {
            /* Broadcast */
            memset(ha, 0xff, sizeof(ha));
        } else {
            /* Multicast */
            ha[0] = 0x01;
            ha[1] = 0x00;
            ha[2] = 0x5E;
            ha[3] = ((uint8_t *) & dest)[1] & 0x7f;
            ha[4] = ((uint8_t *) & dest)[2];
            ha[5] = ((uint8_t *) & dest)[3];
        }

        for (dev = nutDeviceList; dev; dev = dev->dev_next) {
            if (dev->dev_type == IFTYP_NET) {
                /*
                 * Set remaining IP header items using a NETBUF clone and calculate 
                 * the checksum.
                 */
                int rc = 0;
                NETBUF *nb_clone = NutNetBufClonePart(nb, NBAF_NETWORK);

                nif = dev->dev_icb;
                ip = nb_clone->nb_nw.vp;
                ip->ip_id = htons(nif->if_pkt_id);
                nif->if_pkt_id++;
                ip->ip_src = nif->if_local_ip;
                ip->ip_ttl = 1;
                ip->ip_sum = 0;
                ip->ip_sum = NutIpChkSum(0, nb_clone->nb_nw.vp, nb_clone->nb_nw.sz);
                if (nif->if_type == IFT_ETHER)
                    rc = (*nif->if_output) (dev, ETHERTYPE_IP, ha, nb_clone);
                else if (nif->if_type == IFT_PPP)
                    rc = (*nif->if_output) (dev, PPP_IP, 0, nb_clone);
                if (rc == 0) {
                    NutNetBufFree(nb_clone);
                }
            }
        }
        return 0;
    }

    /*
     * Get destination's route. This will also return the proper 
     * interface.
     */
    if ((dev = NutIpRouteQuery(dest, &gate)) == 0) {
        NutNetBufFree(nb);
        return -1;
    }

    /*
     * Set remaining IP header items and calculate the checksum.
     */
    nif = dev->dev_icb;
    ip->ip_id = htons(nif->if_pkt_id);
    nif->if_pkt_id++;
    ip->ip_src = nif->if_local_ip;
    ip->ip_sum = 0;
    ip->ip_sum = NutIpChkSum(0, nb->nb_nw.vp, nb->nb_nw.sz);

    /*
     * On Ethernet we query the MAC address of our next hop,
     * which might be the destination or the gateway to this
     * destination.
     */
    if (nif->if_type == IFT_ETHER) {
        /* 
         * Detect directed broadcasts for the local network. In this
         * case don't send ARP queries, but send directly to MAC broadcast
         * address. 
         */
        if ((gate == 0) && ((dest | nif->if_mask) == 0xffffffff)) {
            memset(ha, 0xff, sizeof(ha));
        } else if (NutArpCacheQuery(dev, gate ? gate : dest, ha)) {
            /* Note, that a failed ARP request is not considered a 
               transmission error. It might be caused by a simple 
               packet loss. */
            return 0;
        }
        return (*nif->if_output) (dev, ETHERTYPE_IP, ha, nb);
    } else if (nif->if_type == IFT_PPP)
        return (*nif->if_output) (dev, PPP_IP, 0, nb);

    NutNetBufFree(nb);
    return -1;
}