mac80211: Encrypt "Group addressed privacy" action frames

Previously, the action frames to group address was not encrypted. But
[1] "Table 8-38 Category values" indicates "Mesh" and "Multihop" category
action frames should be encrypted (Group addressed privacy == yes). And the
encyption key should be MGTK ([1] 10.13 Group addressed robust management frame
procedures). So this patch modifies the code to make it suitable for spec.

[1] IEEE Std 802.11-2012

Signed-off-by: Masashi Honma <masashi.honma@gmail.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>

diff --git a/include/linux/ieee80211.h b/include/linux/ieee80211.h
index 7bc9f831972294ed6205c18eab456ffa9a2236aa..4550eb7a3fd470943c090b27fd3a94d57a60b524 100644 (file)
--- a/include/linux/ieee80211.h
+++ b/include/linux/ieee80211.h
@@ -2491,6 +2491,35 @@ static inline bool ieee80211_is_public_action(struct ieee80211_hdr *hdr,
        return mgmt->u.action.category == WLAN_CATEGORY_PUBLIC;
 }
 
+/**
+ * _ieee80211_is_group_privacy_action - check if frame is a group addressed
+ * privacy action frame
+ * @hdr: the frame
+ */
+static inline bool _ieee80211_is_group_privacy_action(struct ieee80211_hdr *hdr)
+{
+       struct ieee80211_mgmt *mgmt = (void *)hdr;
+
+       if (!ieee80211_is_action(hdr->frame_control) ||
+           !is_multicast_ether_addr(hdr->addr1))
+               return false;
+
+       return mgmt->u.action.category == WLAN_CATEGORY_MESH_ACTION ||
+              mgmt->u.action.category == WLAN_CATEGORY_MULTIHOP_ACTION;
+}
+
+/**
+ * ieee80211_is_group_privacy_action - check if frame is a group addressed
+ * privacy action frame
+ * @skb: the skb containing the frame, length will be checked
+ */
+static inline bool ieee80211_is_group_privacy_action(struct sk_buff *skb)
+{
+       if (skb->len < IEEE80211_MIN_ACTION_SIZE)
+               return false;
+       return _ieee80211_is_group_privacy_action((void *)skb->data);
+}
+
 /**
  * ieee80211_tu_to_usec - convert time units (TU) to microseconds
  * @tu: the TUs