bridge: add root port blocking

This is Linux bridge implementation of root port guard.
If BPDU is received from a leaf (edge) port, it should not
be elected as root port.

Why would you want to do this?
If using STP on a bridge and the downstream bridges are not fully
trusted; this prevents a hostile guest for rerouting traffic.

Why not just use netfilter?
Netfilter does not track of follow spanning tree decisions.
It would be difficult and error prone to try and mirror STP
resolution in netfilter module.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
stephen hemminger
2012-11-13 07:53:08 +00:00
committed by David S. Miller
parent a2e01a65cd
commit 1007dd1aa5
5 changed files with 29 additions and 2 deletions

View File

@@ -136,6 +136,7 @@ struct net_bridge_port
unsigned long flags;
#define BR_HAIRPIN_MODE 0x00000001
#define BR_BPDU_GUARD 0x00000002
#define BR_ROOT_BLOCK 0x00000004
#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
u32 multicast_startup_queries_sent;