mac80211: allow driver to generate P1K for IV32

In order to support pre-populating the P1K cache in
iwlwifi hardware for WoWLAN, we need to calculate
the P1K for the current IV32. Allow drivers to get
the P1K for any given IV32 instead of for a given
packet, but keep the packet-based version around as
an inline.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 84770ce..b29456a 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -20,6 +20,7 @@
 #include <linux/device.h>
 #include <linux/ieee80211.h>
 #include <net/cfg80211.h>
+#include <asm/unaligned.h>
 
 /**
  * DOC: Introduction
@@ -2564,6 +2565,18 @@
 ieee80211_get_buffered_bc(struct ieee80211_hw *hw, struct ieee80211_vif *vif);
 
 /**
+ * ieee80211_get_tkip_p1k_iv - get a TKIP phase 1 key for IV32
+ *
+ * This function returns the TKIP phase 1 key for the given IV32.
+ *
+ * @keyconf: the parameter passed with the set key
+ * @iv32: IV32 to get the P1K for
+ * @p1k: a buffer to which the key will be written, as 5 u16 values
+ */
+void ieee80211_get_tkip_p1k_iv(struct ieee80211_key_conf *keyconf,
+			       u32 iv32, u16 *p1k);
+
+/**
  * ieee80211_get_tkip_p1k - get a TKIP phase 1 key
  *
  * This function returns the TKIP phase 1 key for the IV32 taken
@@ -2574,8 +2587,15 @@
  *	with this P1K
  * @p1k: a buffer to which the key will be written, as 5 u16 values
  */
-void ieee80211_get_tkip_p1k(struct ieee80211_key_conf *keyconf,
-			    struct sk_buff *skb, u16 *p1k);
+static inline void ieee80211_get_tkip_p1k(struct ieee80211_key_conf *keyconf,
+					  struct sk_buff *skb, u16 *p1k)
+{
+	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
+	const u8 *data = (u8 *)hdr + ieee80211_hdrlen(hdr->frame_control);
+	u32 iv32 = get_unaligned_le32(&data[4]);
+
+	ieee80211_get_tkip_p1k_iv(keyconf, iv32, p1k);
+}
 
 /**
  * ieee80211_get_tkip_p2k - get a TKIP phase 2 key