Crypto/chcr: support for 48 byte key_len in aes-xts

Added support for 48 byte key length for aes-xts.

Signed-off-by: Ayush Sawal <ayush.sawal@chelsio.com>
Signed-off-by: Devulapally Shiva Krishna <shiva@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/crypto/chelsio/chcr_algo.c b/drivers/crypto/chelsio/chcr_algo.c
index 6b1a656..0d25af4 100644 (file)
--- a/drivers/crypto/chelsio/chcr_algo.c
+++ b/drivers/crypto/chelsio/chcr_algo.c
@@ -1077,7 +1077,14 @@ static int chcr_update_tweak(struct skcipher_request *req, u8 *iv,
 
        keylen = ablkctx->enckey_len / 2;
        key = ablkctx->key + keylen;
-       ret = aes_expandkey(&aes, key, keylen);
+       /* For a 192 bit key remove the padded zeroes which was
+        * added in chcr_xts_setkey
+        */
+       if (KEY_CONTEXT_CK_SIZE_G(ntohl(ablkctx->key_ctx_hdr))
+                       == CHCR_KEYCTX_CIPHER_KEY_SIZE_192)
+               ret = aes_expandkey(&aes, key, keylen - 8);
+       else
+               ret = aes_expandkey(&aes, key, keylen);
        if (ret)
                return ret;
        aes_encrypt(&aes, iv, iv);
@@ -2264,12 +2271,28 @@ static int chcr_aes_xts_setkey(struct crypto_skcipher *cipher, const u8 *key,
        ablkctx->enckey_len = key_len;
        get_aes_decrypt_key(ablkctx->rrkey, ablkctx->key, key_len << 2);
        context_size = (KEY_CONTEXT_HDR_SALT_AND_PAD + key_len) >> 4;
-       ablkctx->key_ctx_hdr =
+       /* Both keys for xts must be aligned to 16 byte boundary
+        * by padding with zeros. So for 24 byte keys padding 8 zeroes.
+        */
+       if (key_len == 48) {
+               context_size = (KEY_CONTEXT_HDR_SALT_AND_PAD + key_len
+                               + 16) >> 4;
+               memmove(ablkctx->key + 32, ablkctx->key + 24, 24);
+               memset(ablkctx->key + 24, 0, 8);
+               memset(ablkctx->key + 56, 0, 8);
+               ablkctx->enckey_len = 64;
+               ablkctx->key_ctx_hdr =
+                       FILL_KEY_CTX_HDR(CHCR_KEYCTX_CIPHER_KEY_SIZE_192,
+                                        CHCR_KEYCTX_NO_KEY, 1,
+                                        0, context_size);
+       } else {
+               ablkctx->key_ctx_hdr =
                FILL_KEY_CTX_HDR((key_len == AES_KEYSIZE_256) ?
                                 CHCR_KEYCTX_CIPHER_KEY_SIZE_128 :
                                 CHCR_KEYCTX_CIPHER_KEY_SIZE_256,
                                 CHCR_KEYCTX_NO_KEY, 1,
                                 0, context_size);
+       }
        ablkctx->ciph_mode = CHCR_SCMD_CIPHER_MODE_AES_XTS;
        return 0;
 badkey_err: