bsd/netat/ddp_brt.c

   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) 1988, 1989 Apple Computer, Inc.
  24  *
  25  *   Modified, March 17, 1997 by Tuyen Nguyen for MacOSX.
  26  */
  27
  28 #ifndef lint
  29 /* static char sccsid[] = "@(#)ddp_brt.c: 2.0, 1.7; 10/4/93; Copyright 1988-89, Apple Computer, Inc."; */
  30 #endif  /* lint */
  31
  32 /*
  33  * Title:       ddp_brt.c
  34  *
  35  * Facility:    Best Router Caching.
  36  *
  37  * Author:      Kumar Vora, Creation Date: June-15-1989
  38  *
  39  */
  40
  41 #include <sys/errno.h>
  42 #include <sys/types.h>
  43 #include <sys/param.h>
  44 #include <machine/spl.h>
  45 #include <sys/systm.h>
  46 #include <sys/kernel.h>
  47 #include <sys/proc.h>
  48 #include <sys/filedesc.h>
  49 #include <sys/fcntl.h>
  50 #include <sys/mbuf.h>
  51 #include <sys/ioctl.h>
  52 #include <sys/malloc.h>
  53 #include <sys/socket.h>
  54 #include <sys/socketvar.h>
  55 #include <sys/protosw.h>
  56
  57 #include <net/if.h>
  58
  59 #include <netat/appletalk.h>
  60 #include <netat/sysglue.h>
  61 #include <netat/ddp.h>
  62 #include <netat/at_pcb.h>
  63 #include <netat/at_var.h>
  64 #include <netat/at_ddp_brt.h>
  65 #include <netat/debug.h>
  66
  67 /* Best Router Cache */
  68 ddp_brt_t at_ddp_brt[BRTSIZE];
  69 int ddp_brt_sweep_timer;
  70
  71 void ddp_glean(mp, ifID, src_addr)
  72      register gbuf_t      *mp;
  73      register at_ifaddr_t  *ifID;
  74      struct etalk_addr  *src_addr;
  75 {
  76         register at_net_al           src_net;
  77
  78         /* NOT assuming that the incoming packet is in one contiguous
  79          * buffer.
  80          */
  81
  82         {
  83                 /* The interface is ethertalk, so the message is
  84                  * of the form {802.3, 802.2, ddp.... }. Extract the
  85                  * 802.3 source address if necessary.  Assuming,
  86                  * however, that 802.3 and 802.2 headers are in
  87                  * one contiguous piece.
  88                  */
  89                 {       register at_ddp_t    *dgp;
  90
  91                         dgp = (at_ddp_t *)(gbuf_rptr(mp));
  92                         src_net = NET_VALUE(dgp->src_net);
  93                 }
  94                 if (src_net >= ifID->ifThisCableStart && src_net <= ifID->ifThisCableEnd)
  95                         /* the packet has come from a net on this cable,
  96                          * no need to glean router info.
  97                          */
  98                         return;
  99
 100                 if (src_addr != NULL)
 101                 {       register ddp_brt_t   *brt;
 102
 103                         BRT_LOOK (brt, src_net);
 104                         if (brt == NULL) {
 105                                 /* There's no BRT entry corresponding to this
 106                                  * net. Allocate a new entry.
 107                                  */
 108                                 NEW_BRT(brt, src_net);
 109                                 if (brt == NULL)
 110                                         /* No space available in the BRT;
 111                                          * can't glean info.
 112                                          */
 113                                         return;
 114                                 brt->net = src_net;
 115                         }
 116                         /*
 117                          * update the router info in either case
 118                          */
 119                         brt->et_addr = *src_addr;
 120                         brt->age_flag = BRT_VALID;
 121                         brt->ifID = ifID;
 122                 }
 123         }
 124 }
 125
 126 void ddp_brt_init()
 127 {
 128         bzero(at_ddp_brt, sizeof(at_ddp_brt));
 129         ddp_brt_sweep_timer = 1;
 130 #ifdef NOT_USED
 131         timeout(ddp_brt_sweep_funnel, (long)0, BRT_SWEEP_INT * SYS_HZ);
 132 #endif
 133 }
 134
 135 void ddp_brt_shutdown()
 136 {
 137 #ifdef NOT_USED
 138         bzero(at_ddp_brt, sizeof(at_ddp_brt));
 139         if (ddp_brt_sweep_timer)
 140                 untimeout(ddp_brt_sweep_funnel, 0);
 141 #endif
 142         ddp_brt_sweep_timer = 0;
 143 }
 144
 145 /* funneled version */
 146 void ddp_brt_sweep_funnel()
 147 {
 148         thread_funnel_set(network_flock, TRUE);
 149         ddp_brt_sweep();
 150         thread_funnel_set(network_flock, FALSE);
 151 }
 152
 153 void ddp_brt_sweep()
 154 {
 155         register ddp_brt_t      *brt;
 156         register int            i;
 157
 158         if (ddp_brt_sweep_timer)
 159           if (++ddp_brt_sweep_timer > BRT_SWEEP_INT) {
 160             ddp_brt_sweep_timer = 1;
 161
 162             brt = at_ddp_brt;
 163             for (i = 0; i < BRTSIZE; i++, brt++) {
 164                 switch (brt->age_flag) {
 165                 case BRT_EMPTY :
 166                         break;
 167                 case BRT_VALID :
 168                         brt->age_flag = BRT_GETTING_OLD;
 169                         break;
 170                 case BRT_GETTING_OLD :
 171                         bzero(brt, sizeof(ddp_brt_t));
 172                         break;
 173                 default :
 174                         ATTRACE(AT_MID_DDP,AT_SID_RESOURCE, AT_LV_ERROR, FALSE,
 175                                 "ddp_brt_sweep : corrupt age flag %d",
 176                                 brt->age_flag, 0,0);
 177                         break;
 178                 }
 179             }
 180           }
 181 #ifdef NOT_USED
 182         /* set up the next sweep... */
 183         timeout(ddp_brt_sweep_funnel, (long)0, BRT_SWEEP_INT * SYS_HZ);
 184 #endif
 185
 186 }
 187
 188