bridge: Extend Proxy ARP design to allow optional rules for Wi-Fi

This extends the design in commit 958501163ddd ("bridge: Add support for
IEEE 802.11 Proxy ARP") with optional set of rules that are needed to
meet the IEEE 802.11 and Hotspot 2.0 requirements for ProxyARP. The
previously added BR_PROXYARP behavior is left as-is and a new
BR_PROXYARP_WIFI alternative is added so that this behavior can be
configured from user space when required.

In addition, this enables proxyarp functionality for unicast ARP
requests for both BR_PROXYARP and BR_PROXYARP_WIFI since it is possible
to use unicast as well as broadcast for these frames.

The key differences in functionality:

BR_PROXYARP:
- uses the flag on the bridge port on which the request frame was
  received to determine whether to reply
- block bridge port flooding completely on ports that enable proxy ARP

BR_PROXYARP_WIFI:
- uses the flag on the bridge port to which the target device of the
  request belongs
- block bridge port flooding selectively based on whether the proxyarp
  functionality replied

Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/if_bridge.h b/include/linux/if_bridge.h
index a57bca2..dad8b00 100644
--- a/include/linux/if_bridge.h
+++ b/include/linux/if_bridge.h
@@ -44,6 +44,7 @@ struct br_ip_list {
 #define BR_PROMISC		BIT(7)
 #define BR_PROXYARP		BIT(8)
 #define BR_LEARNING_SYNC	BIT(9)
+#define BR_PROXYARP_WIFI	BIT(10)
 
 extern void brioctl_set(int (*ioctl_hook)(struct net *, unsigned int, void __user *));