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, 66 insertions, 7 deletions

diff --git a/drivers/net/wireless/rt2x00/rt2x00queue.h b/drivers/net/wireless/rt2x00/rt2x00queue.h
index ff78e52ce43c..37f3f98d58a2 100644
--- a/drivers/net/wireless/rt2x00/rt2x00queue.h
+++ b/drivers/net/wireless/rt2x00/rt2x00queue.h
@@ -87,10 +87,13 @@ enum data_queue_qid {
  *
  * @SKBDESC_DMA_MAPPED_RX: &skb_dma field has been mapped for RX
  * @SKBDESC_DMA_MAPPED_TX: &skb_dma field has been mapped for TX
+ * @FRAME_DESC_IV_STRIPPED: Frame contained a IV/EIV provided by
+ *      mac80211 but was stripped for processing by the driver.
  */
 enum skb_frame_desc_flags {
-        SKBDESC_DMA_MAPPED_RX = (1 << 0),
-        SKBDESC_DMA_MAPPED_TX = (1 << 1),
+        SKBDESC_DMA_MAPPED_RX = 1 << 0,
+        SKBDESC_DMA_MAPPED_TX = 1 << 1,
+        FRAME_DESC_IV_STRIPPED = 1 << 2,
 };
 
 /**
@@ -104,6 +107,8 @@ enum skb_frame_desc_flags {
  * @desc: Pointer to descriptor part of the frame.
  *      Note that this pointer could point to something outside
  *      of the scope of the skb->data pointer.
+ * @iv: IV data used during encryption/decryption.
+ * @eiv: EIV data used during encryption/decryption.
  * @skb_dma: (PCI-only) the DMA address associated with the sk buffer.
  * @entry: The entry to which this sk buffer belongs.
  */
@@ -113,6 +118,9 @@ struct skb_frame_desc {
         unsigned int desc_len;
         void *desc;
 
+        __le32 iv;
+        __le32 eiv;
+
         dma_addr_t skb_dma;
 
         struct queue_entry *entry;
@@ -152,7 +160,11 @@ enum rxdone_entry_desc_flags {
  * @size: Data size of the received frame.
  * @flags: MAC80211 receive flags (See &enum mac80211_rx_flags).
  * @dev_flags: Ralink receive flags (See &enum rxdone_entry_desc_flags).
-
+ * @cipher: Cipher type used during decryption.
+ * @cipher_status: Decryption status.
+ * @iv: IV data used during decryption.
+ * @eiv: EIV data used during decryption.
+ * @icv: ICV data used during decryption.
  */
 struct rxdone_entry_desc {
         u64 timestamp;
@@ -161,6 +173,12 @@ struct rxdone_entry_desc {
         int size;
         int flags;
         int dev_flags;
+        u8 cipher;
+        u8 cipher_status;
+
+        __le32 iv;
+        __le32 eiv;
+        __le32 icv;
 };
 
 /**
@@ -206,6 +224,10 @@ struct txdone_entry_desc {
  * @ENTRY_TXD_BURST: This frame belongs to the same burst event.
  * @ENTRY_TXD_ACK: An ACK is required for this frame.
  * @ENTRY_TXD_RETRY_MODE: When set, the long retry count is used.
+ * @ENTRY_TXD_ENCRYPT: This frame should be encrypted.
+ * @ENTRY_TXD_ENCRYPT_PAIRWISE: Use pairwise key table (instead of shared).
+ * @ENTRY_TXD_ENCRYPT_IV: Generate IV/EIV in hardware.
+ * @ENTRY_TXD_ENCRYPT_MMIC: Generate MIC in hardware.
  */
 enum txentry_desc_flags {
         ENTRY_TXD_RTS_FRAME,
@@ -218,6 +240,10 @@ enum txentry_desc_flags {
         ENTRY_TXD_BURST,
         ENTRY_TXD_ACK,
         ENTRY_TXD_RETRY_MODE,
+        ENTRY_TXD_ENCRYPT,
+        ENTRY_TXD_ENCRYPT_PAIRWISE,
+        ENTRY_TXD_ENCRYPT_IV,
+        ENTRY_TXD_ENCRYPT_MMIC,
 };
 
 /**
@@ -236,6 +262,9 @@ enum txentry_desc_flags {
  * @ifs: IFS value.
  * @cw_min: cwmin value.
  * @cw_max: cwmax value.
+ * @cipher: Cipher type used for encryption.
+ * @key_idx: Key index used for encryption.
+ * @iv_offset: Position where IV should be inserted by hardware.
  */
 struct txentry_desc {
         unsigned long flags;
@@ -252,6 +281,10 @@ struct txentry_desc {
         short ifs;
         short cw_min;
         short cw_max;
+
+        enum cipher cipher;
+        u16 key_idx;
+        u16 iv_offset;
 };
 
 /**
@@ -484,25 +517,51 @@ static inline int rt2x00queue_threshold(struct data_queue *queue)
 }
 
 /**
- * rt2x00_desc_read - Read a word from the hardware descriptor.
+ * _rt2x00_desc_read - Read a word from the hardware descriptor.
+ * @desc: Base descriptor address
+ * @word: Word index from where the descriptor should be read.
+ * @value: Address where the descriptor value should be written into.
+ */
+static inline void _rt2x00_desc_read(__le32 *desc, const u8 word, __le32 *value)
+{
+        *value = desc[word];
+}
+
+/**
+ * rt2x00_desc_read - Read a word from the hardware descriptor, this
+ * function will take care of the byte ordering.
  * @desc: Base descriptor address
  * @word: Word index from where the descriptor should be read.
  * @value: Address where the descriptor value should be written into.
  */
 static inline void rt2x00_desc_read(__le32 *desc, const u8 word, u32 *value)
 {
-        *value = le32_to_cpu(desc[word]);
+        __le32 tmp;
+        _rt2x00_desc_read(desc, word, &tmp);
+        *value = le32_to_cpu(tmp);
+}
+
+/**
+ * rt2x00_desc_write - write a word to the hardware descriptor, this
+ * function will take care of the byte ordering.
+ * @desc: Base descriptor address
+ * @word: Word index from where the descriptor should be written.
+ * @value: Value that should be written into the descriptor.
+ */
+static inline void _rt2x00_desc_write(__le32 *desc, const u8 word, __le32 value)
+{
+        desc[word] = value;
 }
 
 /**
- * rt2x00_desc_write - wrote a word to the hardware descriptor.
+ * rt2x00_desc_write - write a word to the hardware descriptor.
  * @desc: Base descriptor address
  * @word: Word index from where the descriptor should be written.
  * @value: Value that should be written into the descriptor.
  */
 static inline void rt2x00_desc_write(__le32 *desc, const u8 word, u32 value)
 {
-        desc[word] = cpu_to_le32(value);
+        _rt2x00_desc_write(desc, word, cpu_to_le32(value));
 }
 
 #endif /* RT2X00QUEUE_H */