bridge: Add multicast data-path hooks

This patch finally hooks up the multicast snooping module to the
data path.  In particular, all multicast packets passing through
the bridge are fed into the module and switched by it.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/bridge/br_device.c

@@ -25,6 +25,7 @@ netdev_tx_t br_dev_xmit(struct sk_buff *skb, struct net_device *dev)
 	struct net_bridge *br = netdev_priv(dev);
 	const unsigned char *dest = skb->data;
 	struct net_bridge_fdb_entry *dst;
+	struct net_bridge_mdb_entry *mdst;
 
 	BR_INPUT_SKB_CB(skb)->brdev = dev;
 
@@ -34,13 +35,21 @@ netdev_tx_t br_dev_xmit(struct sk_buff *skb, struct net_device *dev)
 	skb_reset_mac_header(skb);
 	skb_pull(skb, ETH_HLEN);
 
-	if (dest[0] & 1)
+	if (dest[0] & 1) {
+		if (br_multicast_rcv(br, NULL, skb))
+			goto out;
+
+		mdst = br_mdb_get(br, skb);
+		if (mdst || BR_INPUT_SKB_CB(skb)->mrouters_only)
+			br_multicast_deliver(mdst, skb);
+		else
 			br_flood_deliver(br, skb);
-	else if ((dst = __br_fdb_get(br, dest)) != NULL)
+	} else if ((dst = __br_fdb_get(br, dest)) != NULL)
 		br_deliver(dst->dst, skb);
 	else
 		br_flood_deliver(br, skb);
 
+out:
 	return NETDEV_TX_OK;
 }
 

net/bridge/br_input.c

@@ -41,6 +41,7 @@ int br_handle_frame_finish(struct sk_buff *skb)
 	struct net_bridge_port *p = rcu_dereference(skb->dev->br_port);
 	struct net_bridge *br;
 	struct net_bridge_fdb_entry *dst;
+	struct net_bridge_mdb_entry *mdst;
 	struct sk_buff *skb2;
 
 	if (!p || p->state == BR_STATE_DISABLED)
@@ -50,6 +51,10 @@ int br_handle_frame_finish(struct sk_buff *skb)
 	br = p->br;
 	br_fdb_update(br, p, eth_hdr(skb)->h_source);
 
+	if (is_multicast_ether_addr(dest) &&
+	    br_multicast_rcv(br, p, skb))
+		goto drop;
+
 	if (p->state == BR_STATE_LEARNING)
 		goto drop;
 
@@ -64,8 +69,19 @@ int br_handle_frame_finish(struct sk_buff *skb)
 	dst = NULL;
 
 	if (is_multicast_ether_addr(dest)) {
-		br->dev->stats.multicast++;
+		mdst = br_mdb_get(br, skb);
+		if (mdst || BR_INPUT_SKB_CB(skb)->mrouters_only) {
+			if ((mdst && !hlist_unhashed(&mdst->mglist)) ||
+			    br_multicast_is_router(br))
+				skb2 = skb;
+			br_multicast_forward(mdst, skb, skb2);
+			skb = NULL;
+			if (!skb2)
+				goto out;
+		} else
 			skb2 = skb;
+
+		br->dev->stats.multicast++;
 	} else if ((dst = __br_fdb_get(br, dest)) && dst->is_local) {
 		skb2 = skb;
 		/* Do not forward the packet since it's local. */