/**
* \file ccm.h
*
* \brief CCM combines Counter mode encryption with CBC-MAC authentication
* for 128-bit block ciphers.
*
* Input to CCM includes the following elements:
* <ul><li>Payload - data that is both authenticated and encrypted.</li>
* <li>Associated data (Adata) - data that is authenticated but not
* encrypted, For example, a header.</li>
* <li>Nonce - A unique value that is assigned to the payload and the
* associated data.</li></ul>
*
*/
/*
* 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_CCM_H
#define MBEDTLS_CCM_H
#if !defined(MBEDTLS_CONFIG_FILE)
#include "config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif
#include "cipher.h"
#define MBEDTLS_ERR_CCM_BAD_INPUT -0x000D /**< Bad input parameters to the function. */
#define MBEDTLS_ERR_CCM_AUTH_FAILED -0x000F /**< Authenticated decryption failed. */
#define MBEDTLS_ERR_CCM_HW_ACCEL_FAILED -0x0011 /**< CCM hardware accelerator failed. */
#if !defined(MBEDTLS_CCM_ALT)
// Regular implementation
//
#ifdef __cplusplus
extern "C" {
#endif
/**
* \brief The CCM context-type definition. The CCM context is passed
* to the APIs called.
*/
typedef struct {
mbedtls_cipher_context_t cipher_ctx; /*!< The cipher context used. */
}
mbedtls_ccm_context;
/**
* \brief This function initializes the specified CCM context,
* to make references valid, and prepare the context
* for mbedtls_ccm_setkey() or mbedtls_ccm_free().
*
* \param ctx The CCM context to initialize.
*/
void mbedtls_ccm_init( mbedtls_ccm_context *ctx );
/**
* \brief This function initializes the CCM context set in the
* \p ctx parameter and sets the encryption key.
*
* \param ctx The CCM context to initialize.
* \param cipher The 128-bit block cipher to use.
* \param key The encryption key.
* \param keybits The key size in bits. This must be acceptable by the cipher.
*
* \return \c 0 on success, or a cipher-specific error code.
*/
int mbedtls_ccm_setkey( mbedtls_ccm_context *ctx,
mbedtls_cipher_id_t cipher,
const unsigned char *key,
unsigned int keybits );
/**
* \brief This function releases and clears the specified CCM context
* and underlying cipher sub-context.
*
* \param ctx The CCM context to clear.
*/
void mbedtls_ccm_free( mbedtls_ccm_context *ctx );
/**
* \brief This function encrypts a buffer using CCM.
*
* \param ctx The CCM context to use for encryption.
* \param length The length of the input data in Bytes.
* \param iv Initialization vector (nonce).
* \param iv_len The length of the IV in Bytes: 7, 8, 9, 10, 11, 12, or 13.
* \param add The additional data field.
* \param add_len The length of additional data in Bytes.
* Must be less than 2^16 - 2^8.
* \param input The buffer holding the input data.
* \param output The buffer holding the output data.
* Must be at least \p length Bytes wide.
* \param tag The buffer holding the tag.
* \param tag_len The length of the tag to generate in Bytes:
* 4, 6, 8, 10, 12, 14 or 16.
*
* \note The tag is written to a separate buffer. To concatenate
* the \p tag with the \p output, as done in <em>RFC-3610:
* Counter with CBC-MAC (CCM)</em>, use
* \p tag = \p output + \p length, and make sure that the
* output buffer is at least \p length + \p tag_len wide.
*
* \return \c 0 on success.
*/
int mbedtls_ccm_encrypt_and_tag( mbedtls_ccm_context *ctx, size_t length,
const unsigned char *iv, size_t iv_len,
const unsigned char *add, size_t add_len,
const unsigned char *input, unsigned char *output,
unsigned char *tag, size_t tag_len );
/**
* \brief This function performs a CCM authenticated decryption of a
* buffer.
*
* \param ctx The CCM context to use for decryption.
* \param length The length of the input data in Bytes.
* \param iv Initialization vector.
* \param iv_len The length of the IV in Bytes: 7, 8, 9, 10, 11, 12, or 13.
* \param add The additional data field.
* \param add_len The length of additional data in Bytes.
* Must be less than 2^16 - 2^8.
* \param input The buffer holding the input data.
* \param output The buffer holding the output data.
* Must be at least \p length Bytes wide.
* \param tag The buffer holding the tag.
* \param tag_len The length of the tag in Bytes.
* 4, 6, 8, 10, 12, 14 or 16.
*
* \return 0 if successful and authenticated, or
* #MBEDTLS_ERR_CCM_AUTH_FAILED if the tag does not match.
*/
int mbedtls_ccm_auth_decrypt( mbedtls_ccm_context *ctx, size_t length,
const unsigned char *iv, size_t iv_len,
const unsigned char *add, size_t add_len,
const unsigned char *input, unsigned char *output,
const unsigned char *tag, size_t tag_len );
#ifdef __cplusplus
}
#endif
#else /* MBEDTLS_CCM_ALT */
#include "ccm_alt.h"
#endif /* MBEDTLS_CCM_ALT */
#ifdef __cplusplus
extern "C" {
#endif
#if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_AES_C)
/**
* \brief The CCM checkup routine.
*
* \return \c 0 on success, or \c 1 on failure.
*/
int mbedtls_ccm_self_test( int verbose );
#endif /* MBEDTLS_SELF_TEST && MBEDTLS_AES_C */
#ifdef __cplusplus
}
#endif
#endif /* MBEDTLS_CCM_H */
