bsd/netat/ddp_aep.c

   1 /*
   2  * Copyright (c) 2006 Apple Computer, Inc. All Rights Reserved.
   3  *
   4  * @APPLE_LICENSE_OSREFERENCE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License.  The rights granted to you under the
  10  * License may not be used to create, or enable the creation or
  11  * redistribution of, unlawful or unlicensed copies of an Apple operating
  12  * system, or to circumvent, violate, or enable the circumvention or
  13  * violation of, any terms of an Apple operating system software license
  14  * agreement.
  15  *
  16  * Please obtain a copy of the License at
  17  * http://www.opensource.apple.com/apsl/ and read it before using this
  18  * file.
  19  *
  20  * The Original Code and all software distributed under the License are
  21  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  22  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  23  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  25  * Please see the License for the specific language governing rights and
  26  * limitations under the License.
  27  *
  28  * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  29  */
  30 /*
  31  *      Copyright (c) 1997-1998 Apple Computer, Inc.
  32  *      All Rights Reserved.
  33  */
  34
  35 /*
  36  *   Modified, March 17, 1997 by Tuyen Nguyen for MacOSX.
  37  */
  38 #include <sys/errno.h>
  39 #include <sys/types.h>
  40 #include <sys/param.h>
  41 #include <machine/spl.h>
  42 #include <sys/systm.h>
  43 #include <sys/kernel.h>
  44 #include <sys/proc.h>
  45 #include <sys/filedesc.h>
  46 #include <sys/fcntl.h>
  47 #include <sys/mbuf.h>
  48 #include <sys/socket.h>
  49 #include <sys/socketvar.h>
  50
  51 #include <net/if.h>
  52
  53 #include <netat/sysglue.h>
  54 #include <netat/appletalk.h>
  55 #include <netat/ep.h>
  56 #include <netat/ddp.h>
  57 #include <netat/debug.h>
  58 #include <netat/at_snmp.h>
  59 #include <netat/at_pcb.h>
  60 #include <netat/at_var.h>
  61
  62 extern snmpStats_t snmpStats;
  63
  64 /****************************************************************/
  65 /*                                                              */
  66 /*                                                              */
  67 /*                      Echo Protocol                           */
  68 /*                                                              */
  69 /*                                                              */
  70 /****************************************************************/
  71
  72 void ep_input (mp, ifID)
  73      gbuf_t     *mp;
  74      register at_ifaddr_t *ifID;
  75 {
  76         register at_ddp_t       *ddp;
  77
  78         snmpStats.ec_echoReq++;
  79         ddp = (at_ddp_t *)gbuf_rptr(mp);
  80
  81         /* ep packets that have a source broadcast can cause
  82          * possible broadcast storms, prevent that here
  83          */
  84         if ( NET_VALUE(ddp->src_net) == 0 || ddp->src_node == 255) {
  85                 gbuf_freem(mp);
  86                 return;
  87         }
  88
  89         /*
  90          * Check if this AEP message is for us or need to be forwarded
  91          */
  92         if (!ROUTING_MODE ||
  93             (ifID->ifThisNode.s_net == NET_VALUE(ddp->dst_net))
  94             && (ifID->ifThisNode.s_node == ddp->dst_node)) {
  95
  96                 dPrintf(D_M_AEP, D_L_INFO, ("aep_input: received for this port from %d:%d\n",
  97                         NET_VALUE(ddp->src_net), ddp->src_node));
  98
  99                 if (ddp->type == DDP_ECHO &&
 100                     ddp->data[0] == EP_REQUEST) {
 101                         ddp->data[0] = EP_REPLY;
 102                         NET_NET(ddp->dst_net, ddp->src_net);
 103                         ddp->dst_node = ddp->src_node;
 104                         ddp->dst_socket = ddp->src_socket;
 105                         /* send the packet out.... */
 106                         snmpStats.ec_echoReply++;
 107                         (void)ddp_output(&mp, (at_socket)EP_SOCKET, FALSE);
 108                 } else
 109                         gbuf_freem(mp);
 110         }
 111         else {
 112                 dPrintf(D_M_AEP, D_L_INFO,
 113                          ("aep_input: calling routing needed  from %d:%d to %d:%d\n",
 114                         NET_VALUE(ddp->src_net), ddp->src_node, NET_VALUE(ddp->dst_net),
 115                         ddp->dst_node));
 116                 routing_needed(mp, ifID, TRUE);
 117         }
 118
 119         return;
 120 }