rt2x00: Implement HW encryption (rt2500usb)

rt2500usb supports hardware encryption.
rt2500usb supports up to 4 shared and pairwise keys.

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/rt2x00/rt2x00crypto.c b/drivers/net/wireless/rt2x00/rt2x00crypto.c
index e0fc7c1..c6709b3 100644
--- a/drivers/net/wireless/rt2x00/rt2x00crypto.c
+++ b/drivers/net/wireless/rt2x00/rt2x00crypto.c
@@ -69,6 +69,18 @@
 	return overhead;
 }
 
+void rt2x00crypto_tx_copy_iv(struct sk_buff *skb, unsigned int iv_len)
+{
+	struct skb_frame_desc *skbdesc = get_skb_frame_desc(skb);
+	unsigned int header_length = ieee80211_get_hdrlen_from_skb(skb);
+
+	if (unlikely(!iv_len))
+		return;
+
+	/* Copy IV/EIV data */
+	memcpy(skbdesc->iv, skb->data + header_length, iv_len);
+}
+
 void rt2x00crypto_tx_remove_iv(struct sk_buff *skb, unsigned int iv_len)
 {
 	struct skb_frame_desc *skbdesc = get_skb_frame_desc(skb);