freebsd-nq/sys/net/bridge.h

143 lines
4.5 KiB
C

/*
* Copyright (c) 1998 Luigi Rizzo
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
extern int do_bridge;
/*
* the hash table for bridge
*/
typedef struct hash_table {
struct ifnet *name ;
unsigned char etheraddr[6] ;
unsigned short used ;
} bdg_hash_table ;
extern bdg_hash_table *bdg_table ;
#define BDG_MAX_PORTS 128
extern unsigned char bdg_addresses[6*BDG_MAX_PORTS];
extern int bdg_ports ;
/*
* out of the 6 bytes, the last ones are more "variable". Since
* we are on a little endian machine, we have to do some gimmick...
*/
#define HASH_SIZE 8192 /* must be a power of 2 */
#define HASH_FN(addr) ( \
ntohs( ((short *)addr)[1] ^ ((short *)addr)[2] ) & (HASH_SIZE -1))
#define IFF_MUTE IFF_LINK2 /* will need a separate flag... */
struct ifnet *bridge_in(struct mbuf *m);
/* bdg_forward frees the mbuf if necessary, returning null */
int bdg_forward (struct mbuf **m, struct ifnet *dst);
#ifdef __i386__
#define BDG_MATCH(a,b) ( \
((unsigned short *)(a))[2] == ((unsigned short *)(b))[2] && \
*((unsigned int *)(a)) == *((unsigned int *)(b)) )
#define IS_ETHER_BROADCAST(a) ( \
*((unsigned int *)(a)) == 0xffffffff && \
((unsigned short *)(a))[2] == 0xffff )
#else
#warning... must complete these for the alpha etc.
#define BDG_MATCH(a,b) (!bcmp(a, b, ETHER_ADDR_LEN) )
#endif
/*
* The following constants are not legal ifnet pointers, and are used
* as return values from the classifier, bridge_dst_lookup()
* The same values are used as index in the statistics arrays,
* with BDG_FORWARD replacing specifically forwarded packets.
*/
#define BDG_BCAST ( (struct ifnet *)1 )
#define BDG_MCAST ( (struct ifnet *)2 )
#define BDG_LOCAL ( (struct ifnet *)3 )
#define BDG_DROP ( (struct ifnet *)4 )
#define BDG_UNKNOWN ( (struct ifnet *)5 )
#define BDG_IN ( (struct ifnet *)7 )
#define BDG_OUT ( (struct ifnet *)8 )
#define BDG_FORWARD ( (struct ifnet *)9 )
#define PF_BDG 3 /* XXX superhack */
/*
* statistics, passed up with sysctl interface and ns -p bdg
*/
#define STAT_MAX (int)BDG_FORWARD
struct bdg_port_stat {
char name[16];
u_long collisions;
u_long p_in[STAT_MAX+1];
} ;
struct bdg_stats {
struct bdg_port_stat s[16];
} ;
#define BDG_STAT(ifp, type) bdg_stats.s[ifp->if_index].p_in[(int)type]++
#ifdef KERNEL
/*
* Find the right pkt destination:
* BDG_BCAST is a broadcast
* BDG_MCAST is a multicast
* BDG_LOCAL is for a local address
* BDG_DROP must be dropped
* other ifp of the dest. interface (incl.self)
*/
static __inline
struct ifnet *
bridge_dst_lookup(struct mbuf *m)
{
struct ether_header *eh = mtod(m, struct ether_header *);
struct ifnet *dst ;
int index ;
u_char *eth_addr = bdg_addresses ;
if (IS_ETHER_BROADCAST(eh->ether_dhost))
return BDG_BCAST ;
if (eh->ether_dhost[0] & 1)
return BDG_MCAST ;
/*
* Lookup local addresses in case one matches.
*/
for (index = bdg_ports, eth_addr = bdg_addresses ;
index ; index--, eth_addr += 6 )
if (BDG_MATCH(eth_addr, eh->ether_dhost) )
return BDG_LOCAL ;
/*
* Look for a possible destination in table
*/
index= HASH_FN( eh->ether_dhost );
dst = bdg_table[index].name;
if ( dst && BDG_MATCH( bdg_table[index].etheraddr, eh->ether_dhost) )
return dst ;
else
return BDG_UNKNOWN ;
}
#endif /* KERNEL */