mac80211: retransmit TDLS teardown packet through AP if not ACKed

Since the TDLS peer station might not receive the teardown
packet (e.g., when in PS), this makes sure the packet is
retransmitted - this time through the AP - if the TDLS peer
didn't ACK the packet.

Signed-off-by: Liad Kaufman <liad.kaufman@intel.com>
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 25 insertions, 0 deletions

diff --git a/include/linux/ieee80211.h b/include/linux/ieee80211.h
index f65b5446d983..4e2bb9107878 100644
--- a/include/linux/ieee80211.h
+++ b/include/linux/ieee80211.h
@@ -19,6 +19,7 @@
 #include <linux/types.h>
 #include <linux/if_ether.h>
 #include <asm/byteorder.h>
+#include <asm/unaligned.h>
 
 /*
  * DS bit usage
@@ -2418,6 +2419,30 @@ static inline bool ieee80211_check_tim(const struct ieee80211_tim_ie *tim,
         return !!(tim->virtual_map[index] & mask);
 }
 
+/**
+ * ieee80211_get_tdls_action - get tdls packet action (or -1, if not tdls packet)
+ * @skb: the skb containing the frame, length will not be checked
+ * @hdr_size: the size of the ieee80211_hdr that starts at skb->data
+ *
+ * This function assumes the frame is a data frame, and that the network header
+ * is in the correct place.
+ */
+static inline int ieee80211_get_tdls_action(struct sk_buff *skb, u32 hdr_size)
+{
+        if (!skb_is_nonlinear(skb) &&
+            skb->len > (skb_network_offset(skb) + 2)) {
+                /* Point to where the indication of TDLS should start */
+                const u8 *tdls_data = skb_network_header(skb) - 2;
+
+                if (get_unaligned_be16(tdls_data) == ETH_P_TDLS &&
+                    tdls_data[2] == WLAN_TDLS_SNAP_RFTYPE &&
+                    tdls_data[3] == WLAN_CATEGORY_TDLS)
+                        return tdls_data[4];
+        }
+
+        return -1;
+}
+
 /* convert time units */
 #define TU_TO_JIFFIES(x)        (usecs_to_jiffies((x) * 1024))
 #define TU_TO_EXP_TIME(x)       (jiffies + TU_TO_JIFFIES(x))