rt2x00: Implement HW encryption

Various rt2x00 devices support hardware encryption.

Most of them require the IV/EIV to be generated by mac80211,
but require it to be provided seperately instead of within
the frame itself. This means that rt2x00lib should extract
the data from the frame and place it in the frame descriptor.
During RX the IV/EIV is provided in the descriptor by the
hardware which means that it should be inserted into the
frame by rt2x00lib.

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 26 insertions, 4 deletions

diff --git a/drivers/net/wireless/rt2x00/rt2x00dev.c b/drivers/net/wireless/rt2x00/rt2x00dev.c
index f42283ad7b0..182952249a1 100644
--- a/drivers/net/wireless/rt2x00/rt2x00dev.c
+++ b/drivers/net/wireless/rt2x00/rt2x00dev.c
@@ -508,6 +508,15 @@ void rt2x00lib_txdone(struct queue_entry *entry,
 	rt2x00queue_unmap_skb(rt2x00dev, entry->skb);
 
 	/*
+	 * If the IV/EIV data was stripped from the frame before it was
+	 * passed to the hardware, we should now reinsert it again because
+	 * mac80211 will expect the the same data to be present it the
+	 * frame as it was passed to us.
+	 */
+	if (test_bit(CONFIG_SUPPORT_HW_CRYPTO, &rt2x00dev->flags))
+		rt2x00crypto_tx_insert_iv(entry->skb);
+
+	/*
 	 * Send frame to debugfs immediately, after this call is completed
 	 * we are going to overwrite the skb->cb array.
 	 */
@@ -585,7 +594,7 @@ void rt2x00lib_rxdone(struct rt2x00_dev *rt2x00dev,
 	struct ieee80211_supported_band *sband;
 	struct ieee80211_hdr *hdr;
 	const struct rt2x00_rate *rate;
-	unsigned int header_size;
+	unsigned int header_length;
 	unsigned int align;
 	unsigned int i;
 	int idx = -1;
@@ -613,10 +622,19 @@ void rt2x00lib_rxdone(struct rt2x00_dev *rt2x00dev,
 	 * The data behind the ieee80211 header must be
 	 * aligned on a 4 byte boundary.
 	 */
-	header_size = ieee80211_get_hdrlen_from_skb(entry->skb);
-	align = ((unsigned long)(entry->skb->data + header_size)) & 3;
+	header_length = ieee80211_get_hdrlen_from_skb(entry->skb);
+	align = ((unsigned long)(entry->skb->data + header_length)) & 3;
 
-	if (align) {
+	/*
+	 * Hardware might have stripped the IV/EIV/ICV data,
+	 * in that case it is possible that the data was
+	 * provided seperately (through hardware descriptor)
+	 * in which case we should reinsert the data into the frame.
+	 */
+	if ((rxdesc.flags & RX_FLAG_IV_STRIPPED)) {
+		rt2x00crypto_rx_insert_iv(entry->skb, align,
+					  header_length, &rxdesc);
+	} else if (align) {
 		skb_push(entry->skb, align);
 		/* Move entire frame in 1 command */
 		memmove(entry->skb->data, entry->skb->data + align,
@@ -657,6 +675,10 @@ void rt2x00lib_rxdone(struct rt2x00_dev *rt2x00dev,
 	    (rxdesc.dev_flags & RXDONE_MY_BSS))
 		rt2x00lib_update_link_stats(&rt2x00dev->link, rxdesc.rssi);
 
+	rt2x00debug_update_crypto(rt2x00dev,
+				  rxdesc.cipher,
+				  rxdesc.cipher_status);
+
 	rt2x00dev->link.qual.rx_success++;
 
 	rx_status->mactime = rxdesc.timestamp;