diff -urN v2.4.20/linux/include/linux/if_bridge.h linux/include/linux/if_bridge.h
--- v2.4.20/linux/include/linux/if_bridge.h	Fri Jun  2 10:27:43 2000
+++ linux/include/linux/if_bridge.h	Fri Nov 29 03:40:47 2002
@@ -38,6 +38,7 @@
 #define BRCTL_SET_PORT_PRIORITY 16
 #define BRCTL_SET_PATH_COST 17
 #define BRCTL_GET_FDB_ENTRIES 18
+#define BRCTL_SET_BRIDGE_IP_MODE 19
 
 #define BR_STATE_DISABLED 0
 #define BR_STATE_LISTENING 1
@@ -66,6 +67,7 @@
 	__u32 tcn_timer_value;
 	__u32 topology_change_timer_value;
 	__u32 gc_timer_value;
+	__u32 ip_mode;
 };
 
 struct __port_info
@@ -102,7 +104,7 @@
 struct net_bridge_port;
 
 extern int (*br_ioctl_hook)(unsigned long arg);
-extern void (*br_handle_frame_hook)(struct sk_buff *skb);
+extern int (*br_handle_frame_hook)(struct sk_buff *skb);
 
 #endif
 
diff -urN v2.4.20/linux/net/bridge/br_input.c linux/net/bridge/br_input.c
--- v2.4.20/linux/net/bridge/br_input.c	Sat Aug  3 12:13:52 2002
+++ linux/net/bridge/br_input.c	Fri Nov 29 03:40:47 2002
@@ -29,7 +29,8 @@
 	return 0;
 }
 
-static void br_pass_frame_up(struct net_bridge *br, struct sk_buff *skb)
+static void
+br_pass_frame_up(struct net_bridge *br, struct sk_buff *skb, int force_local)
 {
 	struct net_device *indev;
 
@@ -41,18 +42,53 @@
 	skb->pkt_type = PACKET_HOST;
 	skb_push(skb, ETH_HLEN);
 	skb->protocol = eth_type_trans(skb, &br->dev);
+	if (skb->pkt_type == PACKET_OTHERHOST && force_local)
+		skb->pkt_type = PACKET_HOST;
 
 	NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_IN, skb, indev, NULL,
 			br_pass_frame_up_finish);
 }
 
+#define frame_up(br, skb, clone, force_local) {				\
+	if (ip_mode) {							\
+		if (htons(ETH_P_ARP) == skb->mac.ethernet->h_proto) {	\
+			struct sk_buff *skb2;				\
+									\
+			if ((skb2 = skb_clone(skb, GFP_ATOMIC)))	\
+				br_pass_frame_up(br, skb2, 1);		\
+		}							\
+		passedup = 1;						\
+	} else if (clone) {						\
+		struct sk_buff *skb2;					\
+									\
+		skb2 = skb_clone(skb, GFP_ATOMIC);			\
+		if (skb2) {						\
+			passedup = 1;					\
+			br_pass_frame_up(br, skb2,			\
+					 force_local);			\
+		}							\
+	} else {							\
+		br_pass_frame_up(br, skb, force_local);			\
+	}								\
+}
+
+#define handle_frame(br, p, skb)					\
+	if (ip_mode && passedup) { 					\
+		ret = 1;						\
+		if (PACKET_OTHERHOST != skb->pkt_type)			\
+			goto out;					\
+		memcpy(dest, p->dev->dev_addr, p->dev->addr_len);	\
+		skb->pkt_type = PACKET_HOST;				\
+		goto out;						\
+	}
+
 static int br_handle_frame_finish(struct sk_buff *skb)
 {
 	struct net_bridge *br;
 	unsigned char *dest;
 	struct net_bridge_fdb_entry *dst;
 	struct net_bridge_port *p;
-	int passedup;
+	int passedup, ip_mode, ret;
 
 	dest = skb->mac.ethernet->h_dest;
 
@@ -66,33 +102,43 @@
 		goto err;
 
 	passedup = 0;
+	ret = 0;
 	if (br->dev.flags & IFF_PROMISC) {
-		struct sk_buff *skb2;
-
-		skb2 = skb_clone(skb, GFP_ATOMIC);
-		if (skb2 != NULL) {
-			passedup = 1;
-			br_pass_frame_up(br, skb2);
-		}
+		ip_mode = 0;
+		frame_up(br, skb, 1, 0);
+	} else {
+		ip_mode = (br->ip_mode != 0);
 	}
 
 	if (dest[0] & 1) {
-		br_flood_forward(br, skb, !passedup);
+		br_flood_forward(br, skb, !passedup || ip_mode);
 		if (!passedup)
-			br_pass_frame_up(br, skb);
+			frame_up(br, skb, 0, 1);
+		handle_frame(br, p, skb);
 		goto out;
 	}
 
 	dst = br_fdb_get(br, dest);
-	if (dst != NULL && dst->is_local) {
-		if (!passedup)
-			br_pass_frame_up(br, skb);
-		else
-			kfree_skb(skb);
+	if (dst != NULL &&
+	    (dst->is_local ||
+	     (ip_mode && dst->dst->dev != skb->dev &&
+	      htons(ETH_P_IP) == skb->mac.ethernet->h_proto))) {
 		br_fdb_put(dst);
+		if (!passedup) {
+			frame_up(br, skb, 0, 1);
+			handle_frame(br, p, skb);
+		} else {
+			handle_frame(br, p, skb);
+			kfree_skb(skb);
+		}
 		goto out;
 	}
 
+	if (ip_mode && passedup) {
+		ip_mode = 0;
+		frame_up(br, skb, 1, 0);
+	}
+
 	if (dst != NULL) {
 		br_forward(dst->dst, skb);
 		br_fdb_put(dst);
@@ -103,7 +149,7 @@
 
 out:
 	read_unlock(&br->lock);
-	return 0;
+	return ret;
 
 err:
 	read_unlock(&br->lock);
@@ -112,7 +158,7 @@
 	return 0;
 }
 
-void br_handle_frame(struct sk_buff *skb)
+int br_handle_frame(struct sk_buff *skb)
 {
 	struct net_bridge *br;
 	unsigned char *dest;
@@ -146,25 +192,31 @@
 		goto handle_special_frame;
 
 	if (p->state == BR_STATE_FORWARDING) {
-		NF_HOOK(PF_BRIDGE, NF_BR_PRE_ROUTING, skb, skb->dev, NULL,
-			br_handle_frame_finish);
+		int ret = 0;
+
+		if (!br->ip_mode || br->dev.flags & IFF_PROMISC)
+			NF_HOOK(PF_BRIDGE, NF_BR_PRE_ROUTING,
+				skb, skb->dev, NULL, br_handle_frame_finish);
+		else
+			ret = br_handle_frame_finish(skb);
 		read_unlock(&br->lock);
-		return;
+		return ret;
 	}
 
 err:
 	read_unlock(&br->lock);
 err_nolock:
 	kfree_skb(skb);
-	return;
+	return 0;
 
 handle_special_frame:
 	if (!dest[5]) {
 		br_stp_handle_bpdu(skb);
 		read_unlock(&br->lock);
-		return;
+		return 0;
 	}
 
 	read_unlock(&br->lock);
 	kfree_skb(skb);
+	return 0;
 }
diff -urN v2.4.20/linux/net/bridge/br_ioctl.c linux/net/bridge/br_ioctl.c
--- v2.4.20/linux/net/bridge/br_ioctl.c	Mon Nov 20 22:52:50 2000
+++ linux/net/bridge/br_ioctl.c	Fri Nov 29 03:40:47 2002
@@ -73,6 +73,7 @@
 		b.tcn_timer_value = br_timer_get_residue(&br->tcn_timer);
 		b.topology_change_timer_value = br_timer_get_residue(&br->topology_change_timer);
 		b.gc_timer_value = br_timer_get_residue(&br->gc_timer);
+		b.ip_mode = br->ip_mode;
 
 		if (copy_to_user((void *)arg0, &b, sizeof(b)))
 			return -EFAULT;
@@ -179,6 +180,10 @@
 
 	case BRCTL_GET_FDB_ENTRIES:
 		return br_fdb_get_entries(br, (void *)arg0, arg1, arg2);
+
+	case BRCTL_SET_BRIDGE_IP_MODE:
+		br->ip_mode = arg0?1:0;
+		return 0;
 	}
 
 	return -EOPNOTSUPP;
diff -urN v2.4.20/linux/net/bridge/br_private.h linux/net/bridge/br_private.h
--- v2.4.20/linux/net/bridge/br_private.h	Sun Mar 31 06:19:04 2002
+++ linux/net/bridge/br_private.h	Fri Nov 29 03:40:47 2002
@@ -102,6 +102,7 @@
 	unsigned			stp_enabled:1;
 	unsigned			topology_change:1;
 	unsigned			topology_change_detected:1;
+	unsigned			ip_mode:1;
 
 	struct br_timer			hello_timer;
 	struct br_timer			tcn_timer;
@@ -166,7 +167,7 @@
 			   int *ifindices);
 
 /* br_input.c */
-extern void br_handle_frame(struct sk_buff *skb);
+extern int br_handle_frame(struct sk_buff *skb);
 
 /* br_ioctl.c */
 extern void br_call_ioctl_atomic(void (*fn)(void));
diff -urN v2.4.20/linux/net/core/dev.c linux/net/core/dev.c
--- v2.4.20/linux/net/core/dev.c	Fri Nov 29 03:00:18 2002
+++ linux/net/core/dev.c	Fri Nov 29 03:56:53 2002
@@ -1380,7 +1380,7 @@
 
 
 #if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
-void (*br_handle_frame_hook)(struct sk_buff *skb) = NULL;
+int (*br_handle_frame_hook)(struct sk_buff *skb) = NULL;
 #endif
 
 static __inline__ int handle_bridge(struct sk_buff *skb,
@@ -1397,7 +1397,6 @@
 		}
 	}
 
-	br_handle_frame_hook(skb);
 	return ret;
 }
 
@@ -1457,7 +1456,12 @@
 #if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
 	if (skb->dev->br_port != NULL &&
 	    br_handle_frame_hook != NULL) {
-		return handle_bridge(skb, pt_prev);
+		int ret;
+
+		ret = handle_bridge(skb, pt_prev);
+		if (br_handle_frame_hook(skb) == 0)
+			return ret;
+		pt_prev = NULL;
 	}
 #endif