This patch fixes some packet leakage in bridge.  The bridging code was
allowing forward table entries to be generated even if a device was
being blocked. The fix is to not add forwarding database entries
unless the port is active.

The bug arose as part of the conversion to processing STP frames
through normal receive path (in 2.6.17).
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Acked-by: NJohn W. Linville <linville@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If a bridge is not running STP, then it has no way to detect a cycle
in the network. But if it is not running STP and some other machine
or device is running STP, then if STP BPDU's get forwarded to it can
detect the cycle.

This is how the old 2.4 and early 2.6 code worked.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pause frames should never make it out of the network device into
the stack. But if a device was misconfigured, it might happen.
So drop pause frames in bridge.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The change to forward STP bpdu's (for usermode STP) through normal path,
changed the packet type in the process. Since link local stuff is multicast, it
should stay pkt_type = PACKET_MULTICAST.  The code was probably copy/pasted
incorrectly from the bridge pseudo-device receive path.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

While in the STP learning state, don't route packets; wait until
forwarding delay has expired. The purpose of the forwarding delay
is to detect loops in the network, and if a brouter started up
and started forwarding, it could cause a flood.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>

Change the bridging hook to be simple function with return value
rather than modifying the skb argument. This could generate better
code and is cleaner.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>

Use logic operations rather than memcmp() to compare destination
address with link local multicast addresses.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It makes sense to add this simple statistic to keep track of received
multicast packets.
Signed-off-by: NStephen Hemminger <shemminger@osdl.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This change allows link local packets (like 802.3ad and Spanning Tree
Protocol) to be processed even when the bridge is not using the port.
It fixes the chicken-egg problem for bridging a bonded device, and
may also fix problems with spanning tree failover.
Signed-off-by: NStephen Hemminger <shemminger@osdl.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Bridge's communicate with each other using Spanning Tree Protocol
over a standard multicast address. There are times when testing or
layering bridges over existing topologies or tunnels, when it is
useful to use alternative multicast addresses for STP packets.

The 802.1d standard has some unused addresses, that can be used for this.
This patch is restrictive in that it only allows one of the possible
addresses in the standard.
Signed-off-by: NStephen Hemminger <shemminger@osdl.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use LLC for the receive path of Spanning Tree Protocol packets.
This allows link local multicast packets to be received by
other protocols (if they care), and uses the existing LLC
code to get STP packets back into bridge code.

The bridge multicast address is also checked, so bridges using
other link local multicast addresses are ignored. This allows
for use of different multicast addresses to define separate STP
domains.
Signed-off-by: NStephen Hemminger <shemminger@osdl.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The netfilter hook that is used to receive frames doesn't need to be a
stub.  It is only called in two ways, both of which ignore the return
value.
Signed-off-by: NStephen Hemminger <shemminger@osdl.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Change Bridge receive path to correctly handle RCU removal of device
from bridge.  Also fixes deadlock between carrier_check and del_nbp.
This replaces the previous deleted flag fix.
Signed-off-by: NStephen Hemminger <shemminger@osdl.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This uses is_multicast_ether_addr() because it has recently been
changed to do the same thing these seperate tests are doing.
Signed-off-by: NKris Katterjohn <kjak@users.sourceforge.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

While in the learning state, run filters but drop the result.
This prevents us from acquiring bad fdb entries in learning state.
Signed-off-by: NStephen Hemminger <shemminger@osdl.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use compare_ether_addr in bridge code.
Signed-off-by: NStephen Hemminger <shemminger@osdl.org>
Signed-off-by: NArnaldo Carvalho de Melo <acme@mandriva.com>

Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This improves the bridge local receive path by avoiding going
through another softirq.  The bridge receive path is already being called
from a netif_receive_skb() there is no point in going through another
receiveq round trip.

Recursion is limited because bridge can never be a port of a bridge
so handle_bridge() always returns.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Avoid poisoning of the bridge forwarding table by frames that have been
dropped by filtering. This prevents spoofed source addresses on hostile
side of bridge from causing packet leakage, a small but possible security
risk.
Signed-off-by: NStephen Hemminger <shemminger@osdl.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!