bsd/netat/ddp_aep.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 /*
  26  *      Copyright (c) 1997-1998 Apple Computer, Inc.
  27  *      All Rights Reserved.
  28  */
  29
  30 /*
  31  *   Modified, March 17, 1997 by Tuyen Nguyen for MacOSX.
  32  */
  33 #include <sys/errno.h>
  34 #include <sys/types.h>
  35 #include <sys/param.h>
  36 #include <machine/spl.h>
  37 #include <sys/systm.h>
  38 #include <sys/kernel.h>
  39 #include <sys/proc.h>
  40 #include <sys/filedesc.h>
  41 #include <sys/fcntl.h>
  42 #include <sys/mbuf.h>
  43 #include <sys/socket.h>
  44 #include <sys/socketvar.h>
  45
  46 #include <net/if.h>
  47
  48 #include <netat/sysglue.h>
  49 #include <netat/appletalk.h>
  50 #include <netat/ep.h>
  51 #include <netat/ddp.h>
  52 #include <netat/debug.h>
  53 #include <netat/at_snmp.h>
  54 #include <netat/at_pcb.h>
  55 #include <netat/at_var.h>
  56
  57 extern snmpStats_t snmpStats;
  58
  59 /****************************************************************/
  60 /*                                                              */
  61 /*                                                              */
  62 /*                      Echo Protocol                           */
  63 /*                                                              */
  64 /*                                                              */
  65 /****************************************************************/
  66
  67 void ep_input (mp, ifID)
  68      gbuf_t     *mp;
  69      register at_ifaddr_t *ifID;
  70 {
  71         register at_ddp_t       *ddp;
  72
  73         snmpStats.ec_echoReq++;
  74         ddp = (at_ddp_t *)gbuf_rptr(mp);
  75
  76         /* ep packets that have a source broadcast can cause
  77          * possible broadcast storms, prevent that here
  78          */
  79         if ( NET_VALUE(ddp->src_net) == 0 || ddp->src_node == 255) {
  80                 gbuf_freem(mp);
  81                 return;
  82         }
  83
  84         /*
  85          * Check if this AEP message is for us or need to be forwarded
  86          */
  87         if (!ROUTING_MODE ||
  88             (ifID->ifThisNode.s_net == NET_VALUE(ddp->dst_net))
  89             && (ifID->ifThisNode.s_node == ddp->dst_node)) {
  90
  91                 dPrintf(D_M_AEP, D_L_INFO, ("aep_input: received for this port from %d:%d\n",
  92                         NET_VALUE(ddp->src_net), ddp->src_node));
  93
  94                 if (ddp->type == DDP_ECHO &&
  95                     ddp->data[0] == EP_REQUEST) {
  96                         ddp->data[0] = EP_REPLY;
  97                         NET_NET(ddp->dst_net, ddp->src_net);
  98                         ddp->dst_node = ddp->src_node;
  99                         ddp->dst_socket = ddp->src_socket;
 100                         /* send the packet out.... */
 101                         snmpStats.ec_echoReply++;
 102                         (void)ddp_output(&mp, (at_socket)EP_SOCKET, FALSE);
 103                 } else
 104                         gbuf_freem(mp);
 105         }
 106         else {
 107                 dPrintf(D_M_AEP, D_L_INFO,
 108                          ("aep_input: calling routing needed  from %d:%d to %d:%d\n",
 109                         NET_VALUE(ddp->src_net), ddp->src_node, NET_VALUE(ddp->dst_net),
 110                         ddp->dst_node));
 111                 routing_needed(mp, ifID, TRUE);
 112         }
 113
 114         return;
 115 }