bridge: implement BPDU blocking
This is Linux bridge implementation of STP protection
(Cisco BPDU guard/Juniper BPDU block). BPDU block disables
the bridge port if a STP BPDU packet is received.
Why would you want to do this?
If running Spanning Tree on bridge, hostile devices on the network
may send BPDU and cause network failure. Enabling bpdu block
will detect and stop this.
How to recover the port?
The port will be restarted if link is brought down, or
removed and reattached. For example:
# ip li set dev eth0 down; ip li set dev eth0 up
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index 22111ff..c92b080 100644
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -135,6 +135,7 @@
unsigned long flags;
#define BR_HAIRPIN_MODE 0x00000001
+#define BR_BPDU_GUARD 0x00000002
#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
u32 multicast_startup_queries_sent;