Bring in files for bridging support.

1 files changed, 142 insertions, 0 deletions

diff --git a/sys/net/bridge.h b/sys/net/bridge.h
new file mode 100644
index 0000000..8dcee07
--- /dev/null
+++ b/sys/net/bridge.h
@@ -0,0 +1,142 @@
+/*
+ * 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 */