4 files changed, 57 insertions, 6 deletions

diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c
index dad4094..a9feb20 100644
--- a/net/bridge/br_input.c
+++ b/net/bridge/br_input.c
@@ -19,7 +19,8 @@
 #include <linux/netfilter_bridge.h>
 #include "br_private.h"
 
-const unsigned char bridge_ula[6] = { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 };
+/* Bridge group multicast address 802.1d (pg 51). */
+const u8 br_group_address[ETH_ALEN] = { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 };
 
 static void br_pass_frame_up(struct net_bridge *br, struct sk_buff *skb)
 {
@@ -108,9 +109,9 @@ static int br_handle_local_finish(struct sk_buff *skb)
 /* Does address match the link local multicast address.
  * 01:80:c2:00:00:0X
  */
-static inline int is_link_local(const unsigned char *dest)
+static inline int is_link_local(const const unsigned char *dest)
 {
-	return memcmp(dest, bridge_ula, 5) == 0 && (dest[5] & 0xf0) == 0;
+	return memcmp(dest, br_group_address, 5) == 0 && (dest[5] & 0xf0) == 0;
 }
 
 /*
diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index 3bc9ad4..86ecea7 100644
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -109,6 +109,7 @@ struct net_bridge
 	unsigned long			bridge_hello_time;
 	unsigned long			bridge_forward_delay;
 
+	u8				group_addr[ETH_ALEN];
 	u16				root_port;
 	unsigned char			stp_enabled;
 	unsigned char			topology_change;
@@ -122,7 +123,7 @@ struct net_bridge
 };
 
 extern struct notifier_block br_device_notifier;
-extern const unsigned char bridge_ula[6];
+extern const u8 br_group_address[ETH_ALEN];
 
 /* called under bridge lock */
 static inline int br_is_root_bridge(const struct net_bridge *br)
diff --git a/net/bridge/br_stp_bpdu.c b/net/bridge/br_stp_bpdu.c
index a99e90e..ed3a544 100644
--- a/net/bridge/br_stp_bpdu.c
+++ b/net/bridge/br_stp_bpdu.c
@@ -47,7 +47,7 @@ static void br_send_bpdu(struct net_bridge_port *p, unsigned char *data, int len
 	skb->dev = dev;
 	skb->protocol = htons(ETH_P_802_2);
 	skb->mac.raw = skb_put(skb, size);
-	memcpy(skb->mac.raw, bridge_ula, ETH_ALEN);
+	memcpy(skb->mac.raw, p->br->group_addr, ETH_ALEN);
 	memcpy(skb->mac.raw+ETH_ALEN, dev->dev_addr, ETH_ALEN);
 	skb->mac.raw[2*ETH_ALEN] = 0;
 	skb->mac.raw[2*ETH_ALEN+1] = length;
@@ -171,7 +171,7 @@ int br_stp_rcv(struct sk_buff *skb, struct net_device *dev,
 	    || !(br->dev->flags & IFF_UP))
 		goto out;
 
-	if (compare_ether_addr(dest, bridge_ula) != 0)
+	if (compare_ether_addr(dest, br->group_addr) != 0)
 		goto out;
 
 	buf = skb_pull(skb, 3);
diff --git a/net/bridge/br_sysfs_br.c b/net/bridge/br_sysfs_br.c
index 6f577f1..96bcb2f 100644
--- a/net/bridge/br_sysfs_br.c
+++ b/net/bridge/br_sysfs_br.c
@@ -242,6 +242,54 @@ static ssize_t show_gc_timer(struct class_device *cd, char *buf)
 }
 static CLASS_DEVICE_ATTR(gc_timer, S_IRUGO, show_gc_timer, NULL);
 
+static ssize_t show_group_addr(struct class_device *cd, char *buf)
+{
+	struct net_bridge *br = to_bridge(cd);
+	return sprintf(buf, "%x:%x:%x:%x:%x:%x\n",
+		       br->group_addr[0], br->group_addr[1],
+		       br->group_addr[2], br->group_addr[3],
+		       br->group_addr[4], br->group_addr[5]);
+}
+
+static ssize_t store_group_addr(struct class_device *cd, const char *buf,
+				    size_t len)
+{
+	struct net_bridge *br = to_bridge(cd);
+	unsigned new_addr[6];
+	int i;
+
+	if (!capable(CAP_NET_ADMIN))
+		return -EPERM;
+
+	if (sscanf(buf, "%x:%x:%x:%x:%x:%x",
+		   &new_addr[0], &new_addr[1], &new_addr[2],
+		   &new_addr[3], &new_addr[4], &new_addr[5]) != 6)
+		return -EINVAL;
+
+	/* Must be 01:80:c2:00:00:0X */
+	for (i = 0; i < 5; i++)
+		if (new_addr[i] != br_group_address[i])
+			return -EINVAL;
+
+	if (new_addr[5] & ~0xf)
+		return -EINVAL;
+
+	if (new_addr[5] == 1 	/* 802.3x Pause address */
+	    || new_addr[5] == 2 /* 802.3ad Slow protocols */
+	    || new_addr[5] == 3) /* 802.1X PAE address */
+		return -EINVAL;
+
+	spin_lock_bh(&br->lock);
+	for (i = 0; i < 6; i++)
+		br->group_addr[i] = new_addr[i];
+	spin_unlock_bh(&br->lock);
+	return len;
+}
+
+static CLASS_DEVICE_ATTR(group_addr, S_IRUGO | S_IWUSR,
+			 show_group_addr, store_group_addr);
+
+
 static struct attribute *bridge_attrs[] = {
 	&class_device_attr_forward_delay.attr,
 	&class_device_attr_hello_time.attr,
@@ -259,6 +307,7 @@ static struct attribute *bridge_attrs[] = {
 	&class_device_attr_tcn_timer.attr,
 	&class_device_attr_topology_change_timer.attr,
 	&class_device_attr_gc_timer.attr,
+	&class_device_attr_group_addr.attr,
 	NULL
 };