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, 2 insertions, 0 deletions

diff --git a/net/bridge/br_sysfs_if.c b/net/bridge/br_sysfs_if.c
index 2de5d91199e8..4905845a94e9 100644
--- a/net/bridge/br_sysfs_if.c
+++ b/net/bridge/br_sysfs_if.c
@@ -171,6 +171,7 @@ BRPORT_ATTR_FLAG(root_block, BR_ROOT_BLOCK);
 BRPORT_ATTR_FLAG(learning, BR_LEARNING);
 BRPORT_ATTR_FLAG(unicast_flood, BR_FLOOD);
 BRPORT_ATTR_FLAG(proxyarp, BR_PROXYARP);
+BRPORT_ATTR_FLAG(proxyarp_wifi, BR_PROXYARP_WIFI);
 
 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
 static ssize_t show_multicast_router(struct net_bridge_port *p, char *buf)
@@ -215,6 +216,7 @@ static const struct brport_attribute *brport_attrs[] = {
 	&brport_attr_multicast_fast_leave,
 #endif
 	&brport_attr_proxyarp,
+	&brport_attr_proxyarp_wifi,
 	NULL
 };