bsd/net/bridge.h

   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) 1998 Luigi Rizzo
  24  *
  25  * Redistribution and use in source and binary forms, with or without
  26  * modification, are permitted provided that the following conditions
  27  * are met:
  28  * 1. Redistributions of source code must retain the above copyright
  29  *    notice, this list of conditions and the following disclaimer.
  30  * 2. Redistributions in binary form must reproduce the above copyright
  31  *    notice, this list of conditions and the following disclaimer in the
  32  *    documentation and/or other materials provided with the distribution.
  33  *
  34  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  35  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  36  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  37  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  38  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  39  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  40  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  41  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  42  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  43  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  44  * SUCH DAMAGE.
  45  *
  46  */
  47 #ifndef _NET_BRIDGE_H_
  48 #define _NET_BRIDGE_H_
  49
  50 extern int do_bridge;
  51 /*
  52  * the hash table for bridge
  53  */
  54 typedef struct hash_table {
  55     struct ifnet *name ;
  56     unsigned char etheraddr[6] ;
  57     unsigned short used ;
  58 } bdg_hash_table ;
  59
  60 extern bdg_hash_table *bdg_table ;
  61
  62 #define BDG_MAX_PORTS 128
  63 extern unsigned char bdg_addresses[6*BDG_MAX_PORTS];
  64 extern int bdg_ports ;
  65
  66 /*
  67  * out of the 6 bytes, the last ones are more "variable". Since
  68  * we are on a little endian machine, we have to do some gimmick...
  69  */
  70 #define HASH_SIZE 8192  /* must be a power of 2 */
  71 #define HASH_FN(addr)   (       \
  72         ntohs( ((short *)addr)[1] ^ ((short *)addr)[2] ) & (HASH_SIZE -1))
  73
  74 #define IFF_MUTE        IFF_LINK2       /* will need a separate flag... */
  75
  76 struct ifnet *bridge_in(struct mbuf *m);
  77 /* bdg_forward frees the mbuf if necessary, returning null */
  78 int bdg_forward (struct mbuf **m, struct ifnet *dst);
  79
  80 #ifdef __i386__
  81 #define BDG_MATCH(a,b) ( \
  82     ((unsigned short *)(a))[2] == ((unsigned short *)(b))[2] && \
  83     *((unsigned int *)(a)) == *((unsigned int *)(b)) )
  84 #define IS_ETHER_BROADCAST(a) ( \
  85         *((unsigned int *)(a)) == 0xffffffff && \
  86         ((unsigned short *)(a))[2] == 0xffff )
  87 #else
  88 #warning... must complete these for the alpha etc.
  89 #define BDG_MATCH(a,b) (!bcmp(a, b, ETHER_ADDR_LEN) )
  90 #endif
  91 /*
  92  * The following constants are not legal ifnet pointers, and are used
  93  * as return values from the classifier, bridge_dst_lookup()
  94  * The same values are used as index in the statistics arrays,
  95  * with BDG_FORWARD replacing specifically forwarded packets.
  96  */
  97 #define BDG_BCAST       ( (struct ifnet *)1 )
  98 #define BDG_MCAST       ( (struct ifnet *)2 )
  99 #define BDG_LOCAL       ( (struct ifnet *)3 )
 100 #define BDG_DROP        ( (struct ifnet *)4 )
 101 #define BDG_UNKNOWN     ( (struct ifnet *)5 )
 102 #define BDG_IN          ( (struct ifnet *)7 )
 103 #define BDG_OUT         ( (struct ifnet *)8 )
 104 #define BDG_FORWARD     ( (struct ifnet *)9 )
 105
 106 #define PF_BDG 3 /* XXX superhack */
 107 /*
 108  * statistics, passed up with sysctl interface and ns -p bdg
 109  */
 110
 111 #define STAT_MAX (int)BDG_FORWARD
 112 struct bdg_port_stat {
 113     char name[16];
 114     u_long collisions;
 115     u_long p_in[STAT_MAX+1];
 116 } ;
 117
 118 struct bdg_stats {
 119     struct bdg_port_stat s[16];
 120 } ;
 121
 122
 123 #define BDG_STAT(ifp, type) bdg_stats.s[ifp->if_index].p_in[(int)type]++
 124
 125 #if KERNEL
 126 /*
 127  * Find the right pkt destination:
 128  *      BDG_BCAST       is a broadcast
 129  *      BDG_MCAST       is a multicast
 130  *      BDG_LOCAL       is for a local address
 131  *      BDG_DROP        must be dropped
 132  *      other           ifp of the dest. interface (incl.self)
 133  */
 134 static __inline
 135 struct ifnet *
 136 bridge_dst_lookup(struct mbuf *m)
 137 {
 138     struct ether_header *eh = mtod(m, struct ether_header *);
 139     struct ifnet *dst ;
 140     int index ;
 141     u_char *eth_addr = bdg_addresses ;
 142
 143     if (IS_ETHER_BROADCAST(eh->ether_dhost))
 144         return BDG_BCAST ;
 145     if (eh->ether_dhost[0] & 1)
 146         return BDG_MCAST ;
 147     /*
 148      * Lookup local addresses in case one matches.
 149      */
 150     for (index = bdg_ports, eth_addr = bdg_addresses ;
 151                  index ; index--, eth_addr += 6 )
 152         if (BDG_MATCH(eth_addr, eh->ether_dhost) )
 153             return BDG_LOCAL ;
 154     /*
 155      * Look for a possible destination in table
 156      */
 157     index= HASH_FN( eh->ether_dhost );
 158     dst = bdg_table[index].name;
 159     if ( dst && BDG_MATCH( bdg_table[index].etheraddr, eh->ether_dhost) )
 160         return dst ;
 161     else
 162         return BDG_UNKNOWN ;
 163 }
 164
 165 #endif /* KERNEL */
 166
 167 #endif /* ! _NET_BRIDGE_H_ */
 168