return nil, Error{
			HTTPStatusCode: http.StatusBadRequest,
			APICode:        "KMS.InternalException",
			Err:            err,
		}
	}

	if n := len(encryptedKey.IV); n != 16 {
		return nil, Error{
			HTTPStatusCode: http.StatusBadRequest,
			APICode:        "KMS.InternalException",
			Err:            fmt.Errorf("invalid iv size: %d", n),
		}
	}

	var aead cipher.AEAD