ip_input.c

一款类linux的操作系统源码

/*
 *  Roadrunner/pk
 *    Copyright (C) 1989-2002  Cornfed Systems, Inc.
 *
 *  The Roadrunner/pk operating system is free software; you can
 *  redistribute and/or modify it under the terms of the GNU General
 *  Public License, version 2, as published by the Free Software
 *  Foundation.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public
 *  License along with this program; if not, write to the Free
 *  Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 *  MA 02111-1307 USA
 *
 *  More information about the Roadrunner/pk operating system of
 *  which this file is a part is available on the World-Wide Web
 *  at: http://www.cornfed.com.
 *
 */

#include <net/ether.h>
#include <net/icmp.h>
#include <net/ip.h>
#include <net/tcp.h>
#if _DEBUG_IP
#include <stdio.h>
#endif

void
ip_input(buf_t b)
{
    etherhdr_t eh = (etherhdr_t) bstart(b);
    iphdr_t ih = (iphdr_t) eh->data;

    switch (ih->pr) {
    case IP_PROTOCOL_ICMP:
	icmp_input(b);
	break;

    case IP_PROTOCOL_TCP:
	tcp_input(b);
	break;

    case IP_PROTOCOL_UDP:
#if _DEBUG_IP
	kprintf("ip_input: udp packet\n");
#endif
	brel(b);
	break;

    default:
#if _DEBUG_IP
	kprintf("ip_input: unsupported protocol type (%01x)\n", ih->pr);
#endif
	brel(b);
    }
}