/**
 * @file
 * Encryption/decryption module documentation file.
 *
 *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
 *  SPDX-License-Identifier: Apache-2.0
 *
 *  Licensed under the Apache License, Version 2.0 (the "License"); you may
 *  not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 *  This file is part of mbed TLS (https://tls.mbed.org)
 */

/**
 * @addtogroup encdec_module Encryption/decryption module
 *
 * The Encryption/decryption module provides encryption/decryption functions.
 * One can differentiate between symmetric and asymmetric algorithms; the
 * symmetric ones are mostly used for message confidentiality and the asymmetric
 * ones for key exchange and message integrity.
 * Some symmetric algorithms provide different block cipher modes, mainly
 * Electronic Code Book (ECB) which is used for short (64-bit) messages and
 * Cipher Block Chaining (CBC) which provides the structure needed for longer
 * messages. In addition the Cipher Feedback Mode (CFB-128) stream cipher mode,
 * Counter mode (CTR) and Galois Counter Mode (GCM) are implemented for
 * specific algorithms.
 *
 * All symmetric encryption algorithms are accessible via the generic cipher layer
 * (see \c mbedtls_cipher_setup()).
 *
 * The asymmetric encryptrion algorithms are accessible via the generic public
 * key layer (see \c mbedtls_pk_init()).
 *
 * The following algorithms are provided:
 * - Symmetric:
 *   - AES (see \c mbedtls_aes_crypt_ecb(), \c mbedtls_aes_crypt_cbc(), \c mbedtls_aes_crypt_cfb128() and
 *     \c mbedtls_aes_crypt_ctr()).
 *   - ARCFOUR (see \c mbedtls_arc4_crypt()).
 *   - Blowfish / BF (see \c mbedtls_blowfish_crypt_ecb(), \c mbedtls_blowfish_crypt_cbc(),
 *     \c mbedtls_blowfish_crypt_cfb64() and \c mbedtls_blowfish_crypt_ctr())
 *   - Camellia (see \c mbedtls_camellia_crypt_ecb(), \c mbedtls_camellia_crypt_cbc(),
 *     \c mbedtls_camellia_crypt_cfb128() and \c mbedtls_camellia_crypt_ctr()).
 *   - DES/3DES (see \c mbedtls_des_crypt_ecb(), \c mbedtls_des_crypt_cbc(), \c mbedtls_des3_crypt_ecb()
 *     and \c mbedtls_des3_crypt_cbc()).
 *   - GCM (AES-GCM and CAMELLIA-GCM) (see \c mbedtls_gcm_init())
 *   - XTEA (see \c mbedtls_xtea_crypt_ecb()).
 * - Asymmetric:
 *   - Diffie-Hellman-Merkle (see \c mbedtls_dhm_read_public(), \c mbedtls_dhm_make_public()
 *     and \c mbedtls_dhm_calc_secret()).
 *   - RSA (see \c mbedtls_rsa_public() and \c mbedtls_rsa_private()).
 *   - Elliptic Curves over GF(p) (see \c mbedtls_ecp_point_init()).
 *   - Elliptic Curve Digital Signature Algorithm (ECDSA) (see \c mbedtls_ecdsa_init()).
 *   - Elliptic Curve Diffie Hellman (ECDH) (see \c mbedtls_ecdh_init()).
 *
 * This module provides encryption/decryption which can be used to provide
 * secrecy.
 *
 * It also provides asymmetric key functions which can be used for
 * confidentiality, integrity, authentication and non-repudiation.
 */