|  | /** | 
|  | * \file cipher.h | 
|  | * | 
|  | * \brief The generic cipher wrapper. | 
|  | * | 
|  | * \author Adriaan de Jong <dejong@fox-it.com> | 
|  | */ | 
|  | /* | 
|  | *  Copyright (C) 2006-2018, Arm Limited (or its affiliates), 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) | 
|  | */ | 
|  |  | 
|  | #ifndef MBEDTLS_CIPHER_H | 
|  | #define MBEDTLS_CIPHER_H | 
|  |  | 
|  | #if !defined(MBEDTLS_CONFIG_FILE) | 
|  | #include "config.h" | 
|  | #else | 
|  | #include MBEDTLS_CONFIG_FILE | 
|  | #endif | 
|  |  | 
|  | #include <stddef.h> | 
|  |  | 
|  | #if defined(MBEDTLS_GCM_C) || defined(MBEDTLS_CCM_C) | 
|  | #define MBEDTLS_CIPHER_MODE_AEAD | 
|  | #endif | 
|  |  | 
|  | #if defined(MBEDTLS_CIPHER_MODE_CBC) | 
|  | #define MBEDTLS_CIPHER_MODE_WITH_PADDING | 
|  | #endif | 
|  |  | 
|  | #if defined(MBEDTLS_ARC4_C) | 
|  | #define MBEDTLS_CIPHER_MODE_STREAM | 
|  | #endif | 
|  |  | 
|  | #if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \ | 
|  | !defined(inline) && !defined(__cplusplus) | 
|  | #define inline __inline | 
|  | #endif | 
|  |  | 
|  | #define MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE  -0x6080  /**< The selected feature is not available. */ | 
|  | #define MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA       -0x6100  /**< Bad input parameters. */ | 
|  | #define MBEDTLS_ERR_CIPHER_ALLOC_FAILED         -0x6180  /**< Failed to allocate memory. */ | 
|  | #define MBEDTLS_ERR_CIPHER_INVALID_PADDING      -0x6200  /**< Input data contains invalid padding and is rejected. */ | 
|  | #define MBEDTLS_ERR_CIPHER_FULL_BLOCK_EXPECTED  -0x6280  /**< Decryption of block requires a full block. */ | 
|  | #define MBEDTLS_ERR_CIPHER_AUTH_FAILED          -0x6300  /**< Authentication failed (for AEAD modes). */ | 
|  | #define MBEDTLS_ERR_CIPHER_INVALID_CONTEXT      -0x6380  /**< The context is invalid. For example, because it was freed. */ | 
|  | #define MBEDTLS_ERR_CIPHER_HW_ACCEL_FAILED      -0x6400  /**< Cipher hardware accelerator failed. */ | 
|  |  | 
|  | #define MBEDTLS_CIPHER_VARIABLE_IV_LEN     0x01    /**< Cipher accepts IVs of variable length. */ | 
|  | #define MBEDTLS_CIPHER_VARIABLE_KEY_LEN    0x02    /**< Cipher accepts keys of variable length. */ | 
|  |  | 
|  | #ifdef __cplusplus | 
|  | extern "C" { | 
|  | #endif | 
|  |  | 
|  | /** | 
|  | * \brief     An enumeration of supported ciphers. | 
|  | * | 
|  | * \warning   ARC4 and DES are considered weak ciphers and their use | 
|  | *            constitutes a security risk. We recommend considering stronger | 
|  | *            ciphers instead. | 
|  | */ | 
|  | typedef enum { | 
|  | MBEDTLS_CIPHER_ID_NONE = 0, | 
|  | MBEDTLS_CIPHER_ID_NULL, | 
|  | MBEDTLS_CIPHER_ID_AES, | 
|  | MBEDTLS_CIPHER_ID_DES, | 
|  | MBEDTLS_CIPHER_ID_3DES, | 
|  | MBEDTLS_CIPHER_ID_CAMELLIA, | 
|  | MBEDTLS_CIPHER_ID_BLOWFISH, | 
|  | MBEDTLS_CIPHER_ID_ARC4, | 
|  | MBEDTLS_CIPHER_ID_ARIA, | 
|  | } mbedtls_cipher_id_t; | 
|  |  | 
|  | /** | 
|  | * \brief     An enumeration of supported (cipher, mode) pairs. | 
|  | * | 
|  | * \warning   ARC4 and DES are considered weak ciphers and their use | 
|  | *            constitutes a security risk. We recommend considering stronger | 
|  | *            ciphers instead. | 
|  | */ | 
|  | typedef enum { | 
|  | MBEDTLS_CIPHER_NONE = 0, | 
|  | MBEDTLS_CIPHER_NULL, | 
|  | MBEDTLS_CIPHER_AES_128_ECB, | 
|  | MBEDTLS_CIPHER_AES_192_ECB, | 
|  | MBEDTLS_CIPHER_AES_256_ECB, | 
|  | MBEDTLS_CIPHER_AES_128_CBC, | 
|  | MBEDTLS_CIPHER_AES_192_CBC, | 
|  | MBEDTLS_CIPHER_AES_256_CBC, | 
|  | MBEDTLS_CIPHER_AES_128_CFB128, | 
|  | MBEDTLS_CIPHER_AES_192_CFB128, | 
|  | MBEDTLS_CIPHER_AES_256_CFB128, | 
|  | MBEDTLS_CIPHER_AES_128_CTR, | 
|  | MBEDTLS_CIPHER_AES_192_CTR, | 
|  | MBEDTLS_CIPHER_AES_256_CTR, | 
|  | MBEDTLS_CIPHER_AES_128_GCM, | 
|  | MBEDTLS_CIPHER_AES_192_GCM, | 
|  | MBEDTLS_CIPHER_AES_256_GCM, | 
|  | MBEDTLS_CIPHER_CAMELLIA_128_ECB, | 
|  | MBEDTLS_CIPHER_CAMELLIA_192_ECB, | 
|  | MBEDTLS_CIPHER_CAMELLIA_256_ECB, | 
|  | MBEDTLS_CIPHER_CAMELLIA_128_CBC, | 
|  | MBEDTLS_CIPHER_CAMELLIA_192_CBC, | 
|  | MBEDTLS_CIPHER_CAMELLIA_256_CBC, | 
|  | MBEDTLS_CIPHER_CAMELLIA_128_CFB128, | 
|  | MBEDTLS_CIPHER_CAMELLIA_192_CFB128, | 
|  | MBEDTLS_CIPHER_CAMELLIA_256_CFB128, | 
|  | MBEDTLS_CIPHER_CAMELLIA_128_CTR, | 
|  | MBEDTLS_CIPHER_CAMELLIA_192_CTR, | 
|  | MBEDTLS_CIPHER_CAMELLIA_256_CTR, | 
|  | MBEDTLS_CIPHER_CAMELLIA_128_GCM, | 
|  | MBEDTLS_CIPHER_CAMELLIA_192_GCM, | 
|  | MBEDTLS_CIPHER_CAMELLIA_256_GCM, | 
|  | MBEDTLS_CIPHER_DES_ECB, | 
|  | MBEDTLS_CIPHER_DES_CBC, | 
|  | MBEDTLS_CIPHER_DES_EDE_ECB, | 
|  | MBEDTLS_CIPHER_DES_EDE_CBC, | 
|  | MBEDTLS_CIPHER_DES_EDE3_ECB, | 
|  | MBEDTLS_CIPHER_DES_EDE3_CBC, | 
|  | MBEDTLS_CIPHER_BLOWFISH_ECB, | 
|  | MBEDTLS_CIPHER_BLOWFISH_CBC, | 
|  | MBEDTLS_CIPHER_BLOWFISH_CFB64, | 
|  | MBEDTLS_CIPHER_BLOWFISH_CTR, | 
|  | MBEDTLS_CIPHER_ARC4_128, | 
|  | MBEDTLS_CIPHER_AES_128_CCM, | 
|  | MBEDTLS_CIPHER_AES_192_CCM, | 
|  | MBEDTLS_CIPHER_AES_256_CCM, | 
|  | MBEDTLS_CIPHER_CAMELLIA_128_CCM, | 
|  | MBEDTLS_CIPHER_CAMELLIA_192_CCM, | 
|  | MBEDTLS_CIPHER_CAMELLIA_256_CCM, | 
|  | MBEDTLS_CIPHER_ARIA_128_ECB, | 
|  | MBEDTLS_CIPHER_ARIA_192_ECB, | 
|  | MBEDTLS_CIPHER_ARIA_256_ECB, | 
|  | MBEDTLS_CIPHER_ARIA_128_CBC, | 
|  | MBEDTLS_CIPHER_ARIA_192_CBC, | 
|  | MBEDTLS_CIPHER_ARIA_256_CBC, | 
|  | MBEDTLS_CIPHER_ARIA_128_CFB128, | 
|  | MBEDTLS_CIPHER_ARIA_192_CFB128, | 
|  | MBEDTLS_CIPHER_ARIA_256_CFB128, | 
|  | MBEDTLS_CIPHER_ARIA_128_CTR, | 
|  | MBEDTLS_CIPHER_ARIA_192_CTR, | 
|  | MBEDTLS_CIPHER_ARIA_256_CTR, | 
|  | MBEDTLS_CIPHER_ARIA_128_GCM, | 
|  | MBEDTLS_CIPHER_ARIA_192_GCM, | 
|  | MBEDTLS_CIPHER_ARIA_256_GCM, | 
|  | MBEDTLS_CIPHER_ARIA_128_CCM, | 
|  | MBEDTLS_CIPHER_ARIA_192_CCM, | 
|  | MBEDTLS_CIPHER_ARIA_256_CCM, | 
|  | } mbedtls_cipher_type_t; | 
|  |  | 
|  | /** Supported cipher modes. */ | 
|  | typedef enum { | 
|  | MBEDTLS_MODE_NONE = 0, | 
|  | MBEDTLS_MODE_ECB, | 
|  | MBEDTLS_MODE_CBC, | 
|  | MBEDTLS_MODE_CFB, | 
|  | MBEDTLS_MODE_OFB, /* Unused! */ | 
|  | MBEDTLS_MODE_CTR, | 
|  | MBEDTLS_MODE_GCM, | 
|  | MBEDTLS_MODE_STREAM, | 
|  | MBEDTLS_MODE_CCM, | 
|  | } mbedtls_cipher_mode_t; | 
|  |  | 
|  | /** Supported cipher padding types. */ | 
|  | typedef enum { | 
|  | MBEDTLS_PADDING_PKCS7 = 0,     /**< PKCS7 padding (default).        */ | 
|  | MBEDTLS_PADDING_ONE_AND_ZEROS, /**< ISO/IEC 7816-4 padding.         */ | 
|  | MBEDTLS_PADDING_ZEROS_AND_LEN, /**< ANSI X.923 padding.             */ | 
|  | MBEDTLS_PADDING_ZEROS,         /**< zero padding (not reversible). */ | 
|  | MBEDTLS_PADDING_NONE,          /**< never pad (full blocks only).   */ | 
|  | } mbedtls_cipher_padding_t; | 
|  |  | 
|  | /** Type of operation. */ | 
|  | typedef enum { | 
|  | MBEDTLS_OPERATION_NONE = -1, | 
|  | MBEDTLS_DECRYPT = 0, | 
|  | MBEDTLS_ENCRYPT, | 
|  | } mbedtls_operation_t; | 
|  |  | 
|  | enum { | 
|  | /** Undefined key length. */ | 
|  | MBEDTLS_KEY_LENGTH_NONE = 0, | 
|  | /** Key length, in bits (including parity), for DES keys. */ | 
|  | MBEDTLS_KEY_LENGTH_DES  = 64, | 
|  | /** Key length in bits, including parity, for DES in two-key EDE. */ | 
|  | MBEDTLS_KEY_LENGTH_DES_EDE = 128, | 
|  | /** Key length in bits, including parity, for DES in three-key EDE. */ | 
|  | MBEDTLS_KEY_LENGTH_DES_EDE3 = 192, | 
|  | }; | 
|  |  | 
|  | /** Maximum length of any IV, in Bytes. */ | 
|  | #define MBEDTLS_MAX_IV_LENGTH      16 | 
|  | /** Maximum block size of any cipher, in Bytes. */ | 
|  | #define MBEDTLS_MAX_BLOCK_LENGTH   16 | 
|  |  | 
|  | /** | 
|  | * Base cipher information (opaque struct). | 
|  | */ | 
|  | typedef struct mbedtls_cipher_base_t mbedtls_cipher_base_t; | 
|  |  | 
|  | /** | 
|  | * CMAC context (opaque struct). | 
|  | */ | 
|  | typedef struct mbedtls_cmac_context_t mbedtls_cmac_context_t; | 
|  |  | 
|  | /** | 
|  | * Cipher information. Allows calling cipher functions | 
|  | * in a generic way. | 
|  | */ | 
|  | typedef struct { | 
|  | /** Full cipher identifier. For example, | 
|  | * MBEDTLS_CIPHER_AES_256_CBC. | 
|  | */ | 
|  | mbedtls_cipher_type_t type; | 
|  |  | 
|  | /** The cipher mode. For example, MBEDTLS_MODE_CBC. */ | 
|  | mbedtls_cipher_mode_t mode; | 
|  |  | 
|  | /** The cipher key length, in bits. This is the | 
|  | * default length for variable sized ciphers. | 
|  | * Includes parity bits for ciphers like DES. | 
|  | */ | 
|  | unsigned int key_bitlen; | 
|  |  | 
|  | /** Name of the cipher. */ | 
|  | const char * name; | 
|  |  | 
|  | /** IV or nonce size, in Bytes. | 
|  | * For ciphers that accept variable IV sizes, | 
|  | * this is the recommended size. | 
|  | */ | 
|  | unsigned int iv_size; | 
|  |  | 
|  | /** Flags to set. For example, if the cipher supports variable IV sizes or variable key sizes. */ | 
|  | int flags; | 
|  |  | 
|  | /** The block size, in Bytes. */ | 
|  | unsigned int block_size; | 
|  |  | 
|  | /** Struct for base cipher information and functions. */ | 
|  | const mbedtls_cipher_base_t *base; | 
|  |  | 
|  | } mbedtls_cipher_info_t; | 
|  |  | 
|  | /** | 
|  | * Generic cipher context. | 
|  | */ | 
|  | typedef struct { | 
|  | /** Information about the associated cipher. */ | 
|  | const mbedtls_cipher_info_t *cipher_info; | 
|  |  | 
|  | /** Key length to use. */ | 
|  | int key_bitlen; | 
|  |  | 
|  | /** Operation that the key of the context has been | 
|  | * initialized for. | 
|  | */ | 
|  | mbedtls_operation_t operation; | 
|  |  | 
|  | #if defined(MBEDTLS_CIPHER_MODE_WITH_PADDING) | 
|  | /** Padding functions to use, if relevant for | 
|  | * the specific cipher mode. | 
|  | */ | 
|  | void (*add_padding)( unsigned char *output, size_t olen, size_t data_len ); | 
|  | int (*get_padding)( unsigned char *input, size_t ilen, size_t *data_len ); | 
|  | #endif | 
|  |  | 
|  | /** Buffer for input that has not been processed yet. */ | 
|  | unsigned char unprocessed_data[MBEDTLS_MAX_BLOCK_LENGTH]; | 
|  |  | 
|  | /** Number of Bytes that have not been processed yet. */ | 
|  | size_t unprocessed_len; | 
|  |  | 
|  | /** Current IV or NONCE_COUNTER for CTR-mode. */ | 
|  | unsigned char iv[MBEDTLS_MAX_IV_LENGTH]; | 
|  |  | 
|  | /** IV size in Bytes, for ciphers with variable-length IVs. */ | 
|  | size_t iv_size; | 
|  |  | 
|  | /** The cipher-specific context. */ | 
|  | void *cipher_ctx; | 
|  |  | 
|  | #if defined(MBEDTLS_CMAC_C) | 
|  | /** CMAC-specific context. */ | 
|  | mbedtls_cmac_context_t *cmac_ctx; | 
|  | #endif | 
|  | } mbedtls_cipher_context_t; | 
|  |  | 
|  | /** | 
|  | * \brief This function retrieves the list of ciphers supported by the generic | 
|  | * cipher module. | 
|  | * | 
|  | * \return      A statically-allocated array of ciphers. The last entry | 
|  | *              is zero. | 
|  | */ | 
|  | const int *mbedtls_cipher_list( void ); | 
|  |  | 
|  | /** | 
|  | * \brief               This function retrieves the cipher-information | 
|  | *                      structure associated with the given cipher name. | 
|  | * | 
|  | * \param cipher_name   Name of the cipher to search for. | 
|  | * | 
|  | * \return              The cipher information structure associated with the | 
|  | *                      given \p cipher_name, or NULL if not found. | 
|  | */ | 
|  | const mbedtls_cipher_info_t *mbedtls_cipher_info_from_string( const char *cipher_name ); | 
|  |  | 
|  | /** | 
|  | * \brief               This function retrieves the cipher-information | 
|  | *                      structure associated with the given cipher type. | 
|  | * | 
|  | * \param cipher_type   Type of the cipher to search for. | 
|  | * | 
|  | * \return              The cipher information structure associated with the | 
|  | *                      given \p cipher_type, or NULL if not found. | 
|  | */ | 
|  | const mbedtls_cipher_info_t *mbedtls_cipher_info_from_type( const mbedtls_cipher_type_t cipher_type ); | 
|  |  | 
|  | /** | 
|  | * \brief               This function retrieves the cipher-information | 
|  | *                      structure associated with the given cipher ID, | 
|  | *                      key size and mode. | 
|  | * | 
|  | * \param cipher_id     The ID of the cipher to search for. For example, | 
|  | *                      #MBEDTLS_CIPHER_ID_AES. | 
|  | * \param key_bitlen    The length of the key in bits. | 
|  | * \param mode          The cipher mode. For example, #MBEDTLS_MODE_CBC. | 
|  | * | 
|  | * \return              The cipher information structure associated with the | 
|  | *                      given \p cipher_id, or NULL if not found. | 
|  | */ | 
|  | const mbedtls_cipher_info_t *mbedtls_cipher_info_from_values( const mbedtls_cipher_id_t cipher_id, | 
|  | int key_bitlen, | 
|  | const mbedtls_cipher_mode_t mode ); | 
|  |  | 
|  | /** | 
|  | * \brief               This function initializes a \p cipher_context as NONE. | 
|  | */ | 
|  | void mbedtls_cipher_init( mbedtls_cipher_context_t *ctx ); | 
|  |  | 
|  | /** | 
|  | * \brief               This function frees and clears the cipher-specific | 
|  | *                      context of \p ctx. Freeing \p ctx itself remains the | 
|  | *                      responsibility of the caller. | 
|  | */ | 
|  | void mbedtls_cipher_free( mbedtls_cipher_context_t *ctx ); | 
|  |  | 
|  |  | 
|  | /** | 
|  | * \brief               This function initializes and fills the cipher-context | 
|  | *                      structure with the appropriate values. It also clears | 
|  | *                      the structure. | 
|  | * | 
|  | * \param ctx           The context to initialize. May not be NULL. | 
|  | * \param cipher_info   The cipher to use. | 
|  | * | 
|  | * \return              \c 0 on success, | 
|  | *                      #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA on parameter failure, | 
|  | *                      #MBEDTLS_ERR_CIPHER_ALLOC_FAILED if allocation of the | 
|  | *                      cipher-specific context failed. | 
|  | * | 
|  | * \internal Currently, the function also clears the structure. | 
|  | * In future versions, the caller will be required to call | 
|  | * mbedtls_cipher_init() on the structure first. | 
|  | */ | 
|  | int mbedtls_cipher_setup( mbedtls_cipher_context_t *ctx, const mbedtls_cipher_info_t *cipher_info ); | 
|  |  | 
|  | /** | 
|  | * \brief        This function returns the block size of the given cipher. | 
|  | * | 
|  | * \param ctx    The context of the cipher. Must be initialized. | 
|  | * | 
|  | * \return       The size of the blocks of the cipher, or zero if \p ctx | 
|  | *               has not been initialized. | 
|  | */ | 
|  | static inline unsigned int mbedtls_cipher_get_block_size( const mbedtls_cipher_context_t *ctx ) | 
|  | { | 
|  | if( NULL == ctx || NULL == ctx->cipher_info ) | 
|  | return 0; | 
|  |  | 
|  | return ctx->cipher_info->block_size; | 
|  | } | 
|  |  | 
|  | /** | 
|  | * \brief        This function returns the mode of operation for | 
|  | *               the cipher. For example, MBEDTLS_MODE_CBC. | 
|  | * | 
|  | * \param ctx    The context of the cipher. Must be initialized. | 
|  | * | 
|  | * \return       The mode of operation, or #MBEDTLS_MODE_NONE if | 
|  | *               \p ctx has not been initialized. | 
|  | */ | 
|  | static inline mbedtls_cipher_mode_t mbedtls_cipher_get_cipher_mode( const mbedtls_cipher_context_t *ctx ) | 
|  | { | 
|  | if( NULL == ctx || NULL == ctx->cipher_info ) | 
|  | return MBEDTLS_MODE_NONE; | 
|  |  | 
|  | return ctx->cipher_info->mode; | 
|  | } | 
|  |  | 
|  | /** | 
|  | * \brief       This function returns the size of the IV or nonce | 
|  | *              of the cipher, in Bytes. | 
|  | * | 
|  | * \param ctx   The context of the cipher. Must be initialized. | 
|  | * | 
|  | * \return      <ul><li>If no IV has been set: the recommended IV size. | 
|  | *              0 for ciphers not using IV or nonce.</li> | 
|  | *              <li>If IV has already been set: the actual size.</li></ul> | 
|  | */ | 
|  | static inline int mbedtls_cipher_get_iv_size( const mbedtls_cipher_context_t *ctx ) | 
|  | { | 
|  | if( NULL == ctx || NULL == ctx->cipher_info ) | 
|  | return 0; | 
|  |  | 
|  | if( ctx->iv_size != 0 ) | 
|  | return (int) ctx->iv_size; | 
|  |  | 
|  | return (int) ctx->cipher_info->iv_size; | 
|  | } | 
|  |  | 
|  | /** | 
|  | * \brief               This function returns the type of the given cipher. | 
|  | * | 
|  | * \param ctx           The context of the cipher. Must be initialized. | 
|  | * | 
|  | * \return              The type of the cipher, or #MBEDTLS_CIPHER_NONE if | 
|  | *                      \p ctx has not been initialized. | 
|  | */ | 
|  | static inline mbedtls_cipher_type_t mbedtls_cipher_get_type( const mbedtls_cipher_context_t *ctx ) | 
|  | { | 
|  | if( NULL == ctx || NULL == ctx->cipher_info ) | 
|  | return MBEDTLS_CIPHER_NONE; | 
|  |  | 
|  | return ctx->cipher_info->type; | 
|  | } | 
|  |  | 
|  | /** | 
|  | * \brief               This function returns the name of the given cipher | 
|  | *                      as a string. | 
|  | * | 
|  | * \param ctx           The context of the cipher. Must be initialized. | 
|  | * | 
|  | * \return              The name of the cipher, or NULL if \p ctx has not | 
|  | *                      been not initialized. | 
|  | */ | 
|  | static inline const char *mbedtls_cipher_get_name( const mbedtls_cipher_context_t *ctx ) | 
|  | { | 
|  | if( NULL == ctx || NULL == ctx->cipher_info ) | 
|  | return 0; | 
|  |  | 
|  | return ctx->cipher_info->name; | 
|  | } | 
|  |  | 
|  | /** | 
|  | * \brief               This function returns the key length of the cipher. | 
|  | * | 
|  | * \param ctx           The context of the cipher. Must be initialized. | 
|  | * | 
|  | * \return              The key length of the cipher in bits, or | 
|  | *                      #MBEDTLS_KEY_LENGTH_NONE if ctx \p has not been | 
|  | *                      initialized. | 
|  | */ | 
|  | static inline int mbedtls_cipher_get_key_bitlen( const mbedtls_cipher_context_t *ctx ) | 
|  | { | 
|  | if( NULL == ctx || NULL == ctx->cipher_info ) | 
|  | return MBEDTLS_KEY_LENGTH_NONE; | 
|  |  | 
|  | return (int) ctx->cipher_info->key_bitlen; | 
|  | } | 
|  |  | 
|  | /** | 
|  | * \brief          This function returns the operation of the given cipher. | 
|  | * | 
|  | * \param ctx      The context of the cipher. Must be initialized. | 
|  | * | 
|  | * \return         The type of operation: #MBEDTLS_ENCRYPT or | 
|  | *                 #MBEDTLS_DECRYPT, or #MBEDTLS_OPERATION_NONE if \p ctx | 
|  | *                 has not been initialized. | 
|  | */ | 
|  | static inline mbedtls_operation_t mbedtls_cipher_get_operation( const mbedtls_cipher_context_t *ctx ) | 
|  | { | 
|  | if( NULL == ctx || NULL == ctx->cipher_info ) | 
|  | return MBEDTLS_OPERATION_NONE; | 
|  |  | 
|  | return ctx->operation; | 
|  | } | 
|  |  | 
|  | /** | 
|  | * \brief               This function sets the key to use with the given context. | 
|  | * | 
|  | * \param ctx           The generic cipher context. May not be NULL. Must have | 
|  | *                      been initialized using mbedtls_cipher_info_from_type() | 
|  | *                      or mbedtls_cipher_info_from_string(). | 
|  | * \param key           The key to use. | 
|  | * \param key_bitlen    The key length to use, in bits. | 
|  | * \param operation     The operation that the key will be used for: | 
|  | *                      #MBEDTLS_ENCRYPT or #MBEDTLS_DECRYPT. | 
|  | * | 
|  | * \returns             \c 0 on success, #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA if | 
|  | *                      parameter verification fails, or a cipher-specific | 
|  | *                      error code. | 
|  | */ | 
|  | int mbedtls_cipher_setkey( mbedtls_cipher_context_t *ctx, const unsigned char *key, | 
|  | int key_bitlen, const mbedtls_operation_t operation ); | 
|  |  | 
|  | #if defined(MBEDTLS_CIPHER_MODE_WITH_PADDING) | 
|  | /** | 
|  | * \brief               This function sets the padding mode, for cipher modes | 
|  | *                      that use padding. | 
|  | * | 
|  | *                      The default passing mode is PKCS7 padding. | 
|  | * | 
|  | * \param ctx           The generic cipher context. | 
|  | * \param mode          The padding mode. | 
|  | * | 
|  | * \returns             \c 0 on success, #MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE | 
|  | *                      if the selected padding mode is not supported, or | 
|  | *                      #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA if the cipher mode | 
|  | *                      does not support padding. | 
|  | */ | 
|  | int mbedtls_cipher_set_padding_mode( mbedtls_cipher_context_t *ctx, mbedtls_cipher_padding_t mode ); | 
|  | #endif /* MBEDTLS_CIPHER_MODE_WITH_PADDING */ | 
|  |  | 
|  | /** | 
|  | * \brief           This function sets the initialization vector (IV) | 
|  | *                  or nonce. | 
|  | * | 
|  | * \param ctx       The generic cipher context. | 
|  | * \param iv        The IV to use, or NONCE_COUNTER for CTR-mode ciphers. | 
|  | * \param iv_len    The IV length for ciphers with variable-size IV. | 
|  | *                  This parameter is discarded by ciphers with fixed-size IV. | 
|  | * | 
|  | * \returns         \c 0 on success, or #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA | 
|  | * | 
|  | * \note            Some ciphers do not use IVs nor nonce. For these | 
|  | *                  ciphers, this function has no effect. | 
|  | */ | 
|  | int mbedtls_cipher_set_iv( mbedtls_cipher_context_t *ctx, | 
|  | const unsigned char *iv, size_t iv_len ); | 
|  |  | 
|  | /** | 
|  | * \brief         This function resets the cipher state. | 
|  | * | 
|  | * \param ctx     The generic cipher context. | 
|  | * | 
|  | * \returns       \c 0 on success, #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA | 
|  | *                if parameter verification fails. | 
|  | */ | 
|  | int mbedtls_cipher_reset( mbedtls_cipher_context_t *ctx ); | 
|  |  | 
|  | #if defined(MBEDTLS_GCM_C) | 
|  | /** | 
|  | * \brief               This function adds additional data for AEAD ciphers. | 
|  | *                      Only supported with GCM. Must be called | 
|  | *                      exactly once, after mbedtls_cipher_reset(). | 
|  | * | 
|  | * \param ctx           The generic cipher context. | 
|  | * \param ad            The additional data to use. | 
|  | * \param ad_len        the Length of \p ad. | 
|  | * | 
|  | * \return              \c 0 on success, or a specific error code on failure. | 
|  | */ | 
|  | int mbedtls_cipher_update_ad( mbedtls_cipher_context_t *ctx, | 
|  | const unsigned char *ad, size_t ad_len ); | 
|  | #endif /* MBEDTLS_GCM_C */ | 
|  |  | 
|  | /** | 
|  | * \brief               The generic cipher update function. It encrypts or | 
|  | *                      decrypts using the given cipher context. Writes as | 
|  | *                      many block-sized blocks of data as possible to output. | 
|  | *                      Any data that cannot be written immediately is either | 
|  | *                      added to the next block, or flushed when | 
|  | *                      mbedtls_cipher_finish() is called. | 
|  | *                      Exception: For MBEDTLS_MODE_ECB, expects a single block | 
|  | *                      in size. For example, 16 Bytes for AES. | 
|  | * | 
|  | * \param ctx           The generic cipher context. | 
|  | * \param input         The buffer holding the input data. | 
|  | * \param ilen          The length of the input data. | 
|  | * \param output        The buffer for the output data. Must be able to hold at | 
|  | *                      least \p ilen + block_size. Must not be the same buffer | 
|  | *                      as input. | 
|  | * \param olen          The length of the output data, to be updated with the | 
|  | *                      actual number of Bytes written. | 
|  | * | 
|  | * \returns             \c 0 on success, #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA if | 
|  | *                      parameter verification fails, | 
|  | *                      #MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE on an | 
|  | *                      unsupported mode for a cipher, or a cipher-specific | 
|  | *                      error code. | 
|  | * | 
|  | * \note                If the underlying cipher is GCM, all calls to this | 
|  | *                      function, except the last one before | 
|  | *                      mbedtls_cipher_finish(). Must have \p ilen as a | 
|  | *                      multiple of the block_size. | 
|  | */ | 
|  | int mbedtls_cipher_update( mbedtls_cipher_context_t *ctx, const unsigned char *input, | 
|  | size_t ilen, unsigned char *output, size_t *olen ); | 
|  |  | 
|  | /** | 
|  | * \brief               The generic cipher finalization function. If data still | 
|  | *                      needs to be flushed from an incomplete block, the data | 
|  | *                      contained in it is padded to the size of | 
|  | *                      the last block, and written to the \p output buffer. | 
|  | * | 
|  | * \param ctx           The generic cipher context. | 
|  | * \param output        The buffer to write data to. Needs block_size available. | 
|  | * \param olen          The length of the data written to the \p output buffer. | 
|  | * | 
|  | * \returns             \c 0 on success, #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA if | 
|  | *                      parameter verification fails, | 
|  | *                      #MBEDTLS_ERR_CIPHER_FULL_BLOCK_EXPECTED if decryption | 
|  | *                      expected a full block but was not provided one, | 
|  | *                      #MBEDTLS_ERR_CIPHER_INVALID_PADDING on invalid padding | 
|  | *                      while decrypting, or a cipher-specific error code | 
|  | *                      on failure for any other reason. | 
|  | */ | 
|  | int mbedtls_cipher_finish( mbedtls_cipher_context_t *ctx, | 
|  | unsigned char *output, size_t *olen ); | 
|  |  | 
|  | #if defined(MBEDTLS_GCM_C) | 
|  | /** | 
|  | * \brief               This function writes a tag for AEAD ciphers. | 
|  | *                      Only supported with GCM. | 
|  | *                      Must be called after mbedtls_cipher_finish(). | 
|  | * | 
|  | * \param ctx           The generic cipher context. | 
|  | * \param tag           The buffer to write the tag to. | 
|  | * \param tag_len       The length of the tag to write. | 
|  | * | 
|  | * \return              \c 0 on success, or a specific error code on failure. | 
|  | */ | 
|  | int mbedtls_cipher_write_tag( mbedtls_cipher_context_t *ctx, | 
|  | unsigned char *tag, size_t tag_len ); | 
|  |  | 
|  | /** | 
|  | * \brief               This function checks the tag for AEAD ciphers. | 
|  | *                      Only supported with GCM. | 
|  | *                      Must be called after mbedtls_cipher_finish(). | 
|  | * | 
|  | * \param ctx           The generic cipher context. | 
|  | * \param tag           The buffer holding the tag. | 
|  | * \param tag_len       The length of the tag to check. | 
|  | * | 
|  | * \return              \c 0 on success, or a specific error code on failure. | 
|  | */ | 
|  | int mbedtls_cipher_check_tag( mbedtls_cipher_context_t *ctx, | 
|  | const unsigned char *tag, size_t tag_len ); | 
|  | #endif /* MBEDTLS_GCM_C */ | 
|  |  | 
|  | /** | 
|  | * \brief               The generic all-in-one encryption/decryption function, | 
|  | *                      for all ciphers except AEAD constructs. | 
|  | * | 
|  | * \param ctx           The generic cipher context. | 
|  | * \param iv            The IV to use, or NONCE_COUNTER for CTR-mode ciphers. | 
|  | * \param iv_len        The IV length for ciphers with variable-size IV. | 
|  | *                      This parameter is discarded by ciphers with fixed-size | 
|  | *                      IV. | 
|  | * \param input         The buffer holding the input data. | 
|  | * \param ilen          The length of the input data. | 
|  | * \param output        The buffer for the output data. Must be able to hold at | 
|  | *                      least \p ilen + block_size. Must not be the same buffer | 
|  | *                      as input. | 
|  | * \param olen          The length of the output data, to be updated with the | 
|  | *                      actual number of Bytes written. | 
|  | * | 
|  | * \note                Some ciphers do not use IVs nor nonce. For these | 
|  | *                      ciphers, use \p iv = NULL and \p iv_len = 0. | 
|  | * | 
|  | * \returns             \c 0 on success, or | 
|  | *                      #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA, or | 
|  | *                      #MBEDTLS_ERR_CIPHER_FULL_BLOCK_EXPECTED if decryption | 
|  | *                      expected a full block but was not provided one, or | 
|  | *                      #MBEDTLS_ERR_CIPHER_INVALID_PADDING on invalid padding | 
|  | *                      while decrypting, or a cipher-specific error code on | 
|  | *                      failure for any other reason. | 
|  | */ | 
|  | int mbedtls_cipher_crypt( mbedtls_cipher_context_t *ctx, | 
|  | const unsigned char *iv, size_t iv_len, | 
|  | const unsigned char *input, size_t ilen, | 
|  | unsigned char *output, size_t *olen ); | 
|  |  | 
|  | #if defined(MBEDTLS_CIPHER_MODE_AEAD) | 
|  | /** | 
|  | * \brief               The generic autenticated encryption (AEAD) function. | 
|  | * | 
|  | * \param ctx           The generic cipher context. | 
|  | * \param iv            The IV to use, or NONCE_COUNTER for CTR-mode ciphers. | 
|  | * \param iv_len        The IV length for ciphers with variable-size IV. | 
|  | *                      This parameter is discarded by ciphers with fixed-size IV. | 
|  | * \param ad            The additional data to authenticate. | 
|  | * \param ad_len        The length of \p ad. | 
|  | * \param input         The buffer holding the input data. | 
|  | * \param ilen          The length of the input data. | 
|  | * \param output        The buffer for the output data. | 
|  | *                      Must be able to hold at least \p ilen. | 
|  | * \param olen          The length of the output data, to be updated with the | 
|  | *                      actual number of Bytes written. | 
|  | * \param tag           The buffer for the authentication tag. | 
|  | * \param tag_len       The desired length of the authentication tag. | 
|  | * | 
|  | * \returns             \c 0 on success, or | 
|  | *                      #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA, or | 
|  | *                      a cipher-specific error code. | 
|  | */ | 
|  | int mbedtls_cipher_auth_encrypt( mbedtls_cipher_context_t *ctx, | 
|  | const unsigned char *iv, size_t iv_len, | 
|  | const unsigned char *ad, size_t ad_len, | 
|  | const unsigned char *input, size_t ilen, | 
|  | unsigned char *output, size_t *olen, | 
|  | unsigned char *tag, size_t tag_len ); | 
|  |  | 
|  | /** | 
|  | * \brief               The generic autenticated decryption (AEAD) function. | 
|  | * | 
|  | * \param ctx           The generic cipher context. | 
|  | * \param iv            The IV to use, or NONCE_COUNTER for CTR-mode ciphers. | 
|  | * \param iv_len        The IV length for ciphers with variable-size IV. | 
|  | *                      This parameter is discarded by ciphers with fixed-size IV. | 
|  | * \param ad            The additional data to be authenticated. | 
|  | * \param ad_len        The length of \p ad. | 
|  | * \param input         The buffer holding the input data. | 
|  | * \param ilen          The length of the input data. | 
|  | * \param output        The buffer for the output data. | 
|  | *                      Must be able to hold at least \p ilen. | 
|  | * \param olen          The length of the output data, to be updated with the | 
|  | *                      actual number of Bytes written. | 
|  | * \param tag           The buffer holding the authentication tag. | 
|  | * \param tag_len       The length of the authentication tag. | 
|  | * | 
|  | * \returns             \c 0 on success, or | 
|  | *                      #MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA, or | 
|  | *                      #MBEDTLS_ERR_CIPHER_AUTH_FAILED if data is not authentic, | 
|  | *                      or a cipher-specific error code on failure for any other reason. | 
|  | * | 
|  | * \note                If the data is not authentic, then the output buffer | 
|  | *                      is zeroed out to prevent the unauthentic plaintext being | 
|  | *                      used, making this interface safer. | 
|  | */ | 
|  | int mbedtls_cipher_auth_decrypt( mbedtls_cipher_context_t *ctx, | 
|  | const unsigned char *iv, size_t iv_len, | 
|  | const unsigned char *ad, size_t ad_len, | 
|  | const unsigned char *input, size_t ilen, | 
|  | unsigned char *output, size_t *olen, | 
|  | const unsigned char *tag, size_t tag_len ); | 
|  | #endif /* MBEDTLS_CIPHER_MODE_AEAD */ | 
|  |  | 
|  | #ifdef __cplusplus | 
|  | } | 
|  | #endif | 
|  |  | 
|  | #endif /* MBEDTLS_CIPHER_H */ |