cipher: Add wrappers for AES-XTS
AES-XTS does not support multipart use as it can only operate on an entire
sector at a time.
diff --git a/include/mbedtls/cipher.h b/include/mbedtls/cipher.h
index 3ee2ab7..2789393 100644
--- a/include/mbedtls/cipher.h
+++ b/include/mbedtls/cipher.h
@@ -145,6 +145,8 @@
MBEDTLS_CIPHER_CAMELLIA_128_CCM, /**< Camellia cipher with 128-bit CCM mode. */
MBEDTLS_CIPHER_CAMELLIA_192_CCM, /**< Camellia cipher with 192-bit CCM mode. */
MBEDTLS_CIPHER_CAMELLIA_256_CCM, /**< Camellia cipher with 256-bit CCM mode. */
+ MBEDTLS_CIPHER_AES_128_XTS, /**< AES 128-bit cipher in XTS block mode. */
+ MBEDTLS_CIPHER_AES_256_XTS, /**< AES 256-bit cipher in XTS block mode. */
} mbedtls_cipher_type_t;
/** Supported cipher modes. */
@@ -158,6 +160,7 @@
MBEDTLS_MODE_GCM, /**< The GCM cipher mode. */
MBEDTLS_MODE_STREAM, /**< The stream cipher mode. */
MBEDTLS_MODE_CCM, /**< The CCM cipher mode. */
+ MBEDTLS_MODE_XTS, /**< The XTS cipher mode. */
} mbedtls_cipher_mode_t;
/** Supported cipher padding types. */
@@ -273,7 +276,8 @@
/** Number of Bytes that have not been processed yet. */
size_t unprocessed_len;
- /** Current IV or NONCE_COUNTER for CTR-mode. */
+ /** Current IV or NONCE_COUNTER for CTR-mode, data unit (or sector) number
+ * for XTS-mode. */
unsigned char iv[MBEDTLS_MAX_IV_LENGTH];
/** IV size in Bytes, for ciphers with variable-length IVs. */
diff --git a/include/mbedtls/cipher_internal.h b/include/mbedtls/cipher_internal.h
index 969ff9c..d4c7a59 100644
--- a/include/mbedtls/cipher_internal.h
+++ b/include/mbedtls/cipher_internal.h
@@ -71,6 +71,13 @@
const unsigned char *input, unsigned char *output );
#endif
+#if defined(MBEDTLS_CIPHER_MODE_XTS)
+ /** Encrypt using XTS */
+ int (*xts_func)( void *ctx, mbedtls_operation_t mode, size_t length,
+ const unsigned char data_unit[16],
+ const unsigned char *input, unsigned char *output );
+#endif
+
#if defined(MBEDTLS_CIPHER_MODE_STREAM)
/** Encrypt using STREAM */
int (*stream_func)( void *ctx, size_t length,