Bluetooth: Add flexible buffer byte order swapping function

Since the SMP code needs to swap ordering of variable length buffers add
a convenience function that can be used for any length buffer.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c
index 72c5aa05a489537289273f599d3c8affa5649a87..28f4ef48095b76daea86134c08d6a105c7c39032 100644 (file)
--- a/net/bluetooth/smp.c
+++ b/net/bluetooth/smp.c
@@ -64,18 +64,12 @@ struct smp_chan {
        unsigned long   flags;
 };
 
-static inline void swap128(const u8 src[16], u8 dst[16])
+static inline void swap_buf(const u8 *src, u8 *dst, size_t len)
 {
-       int i;
-       for (i = 0; i < 16; i++)
-               dst[15 - i] = src[i];
-}
+       size_t i;
 
-static inline void swap56(const u8 src[7], u8 dst[7])
-{
-       int i;
-       for (i = 0; i < 7; i++)
-               dst[6 - i] = src[i];
+       for (i = 0; i < len; i++)
+               dst[len - 1 - i] = src[i];
 }
 
 static int smp_e(struct crypto_blkcipher *tfm, const u8 *k, u8 *r)
@@ -94,7 +88,7 @@ static int smp_e(struct crypto_blkcipher *tfm, const u8 *k, u8 *r)
        desc.flags = 0;
 
        /* The most significant octet of key corresponds to k[0] */
-       swap128(k, tmp);
+       swap_buf(k, tmp, 16);
 
        err = crypto_blkcipher_setkey(tfm, tmp, 16);
        if (err) {
@@ -103,7 +97,7 @@ static int smp_e(struct crypto_blkcipher *tfm, const u8 *k, u8 *r)
        }
 
        /* Most significant octet of plaintextData corresponds to data[0] */
-       swap128(r, data);
+       swap_buf(r, data, 16);
 
        sg_init_one(&sg, data, 16);
 
@@ -112,7 +106,7 @@ static int smp_e(struct crypto_blkcipher *tfm, const u8 *k, u8 *r)
                BT_ERR("Encrypt data error %d", err);
 
        /* Most significant octet of encryptedData corresponds to data[0] */
-       swap128(data, r);
+       swap_buf(data, r, 16);
 
        return err;
 }