LXR darwin-xnu/bsd/netat/ddp

   1/*
   2 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3 *
   4 * @APPLE_LICENSE_HEADER_START@
   5 * 
   6 * The contents of this file constitute Original Code as defined in and
   7 * are subject to the Apple Public Source License Version 1.1 (the
   8 * "License").  You may not use this file except in compliance with the
   9 * License.  Please obtain a copy of the License at
  10 * http://www.apple.com/publicsource and read it before using this file.
  11 * 
  12 * This Original Code and all software distributed under the License are
  13 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17 * License for the specific language governing rights and limitations
  18 * under the License.
  19 * 
  20 * @APPLE_LICENSE_HEADER_END@
  21 */
  22/*
  23 *      Copyright (c) 1997-1998 Apple Computer, Inc.
  24 *      All Rights Reserved.
  25 */
  26
  27/*
  28 *   Modified, March 17, 1997 by Tuyen Nguyen for MacOSX.
  29 */
  30#include <sys/errno.h>
  31#include <sys/types.h>
  32#include <sys/param.h>
  33#include <machine/spl.h>
  34#include <sys/systm.h>
  35#include <sys/kernel.h>
  36#include <sys/proc.h>
  37#include <sys/filedesc.h>
  38#include <sys/fcntl.h>
  39#include <sys/mbuf.h>
  40#include <sys/socket.h>
  41#include <sys/socketvar.h>
  42
  43#include <net/if.h>
  44
  45#include <netat/sysglue.h> 
  46#include <netat/appletalk.h>
  47#include <netat/ep.h>
  48#include <netat/ddp.h>
  49#include <netat/debug.h>
  50#include <netat/at_snmp.h>
  51#include <netat/at_pcb.h>
  52#include <netat/at_var.h>
  53
  54extern snmpStats_t snmpStats;
  55
  56/****************************************************************/
  57/*                                                              */
  58/*                                                              */
  59/*                      Echo Protocol                           */
  60/*                                                              */
  61/*                                                              */
  62/****************************************************************/
  63
  64void ep_input (mp, ifID)
  65     gbuf_t     *mp;
  66     register at_ifaddr_t *ifID;
  67{
  68        register at_ddp_t       *ddp;
  69
  70        snmpStats.ec_echoReq++;
  71        ddp = (at_ddp_t *)gbuf_rptr(mp);
  72
  73        /* ep packets that have a source broadcast can cause
  74         * possible broadcast storms, prevent that here
  75         */
  76        if ( NET_VALUE(ddp->src_net) == 0 || ddp->src_node == 255) {
  77                gbuf_freem(mp);
  78                return;
  79        }
  80        
  81        /*
  82         * Check if this AEP message is for us or need to be forwarded
  83         */
  84        if (!ROUTING_MODE || 
  85            (ifID->ifThisNode.s_net == NET_VALUE(ddp->dst_net))
  86            && (ifID->ifThisNode.s_node == ddp->dst_node)) {
  87
  88                dPrintf(D_M_AEP, D_L_INFO, ("aep_input: received for this port from %d:%d\n",
  89                        NET_VALUE(ddp->src_net), ddp->src_node));
  90
  91                if (ddp->type == DDP_ECHO && 
  92                    ddp->data[0] == EP_REQUEST) {
  93                        ddp->data[0] = EP_REPLY;
  94                        NET_NET(ddp->dst_net, ddp->src_net);
  95                        ddp->dst_node = ddp->src_node;
  96                        ddp->dst_socket = ddp->src_socket;
  97                        /* send the packet out.... */
  98                        snmpStats.ec_echoReply++;
  99                        (void)ddp_output(&mp, (at_socket)EP_SOCKET, FALSE);
 100                } else
 101                        gbuf_freem(mp);
 102        }
 103        else {
 104                dPrintf(D_M_AEP, D_L_INFO,
 105                         ("aep_input: calling routing needed  from %d:%d to %d:%d\n",
 106                        NET_VALUE(ddp->src_net), ddp->src_node, NET_VALUE(ddp->dst_net),
 107                        ddp->dst_node));
 108                routing_needed(mp, ifID, TRUE);
 109        }
 110
 111        return;
 112}
 113