c-libp2p/include/mbedtls/ccm.h
2016-11-03 11:15:18 -05:00

141 lines
4.8 KiB
C

/**
* \file ccm.h
*
* \brief Counter with CBC-MAC (CCM) for 128-bit block ciphers
*
* 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)
*/
#ifndef MBEDTLS_CCM_H
#define MBEDTLS_CCM_H
#include "cipher.h"
#define MBEDTLS_ERR_CCM_BAD_INPUT -0x000D /**< Bad input parameters to function. */
#define MBEDTLS_ERR_CCM_AUTH_FAILED -0x000F /**< Authenticated decryption failed. */
#ifdef __cplusplus
extern "C" {
#endif
/**
* \brief CCM context structure
*/
typedef struct {
mbedtls_cipher_context_t cipher_ctx; /*!< cipher context used */
}
mbedtls_ccm_context;
/**
* \brief Initialize CCM context (just makes references valid)
* Makes the context ready for mbedtls_ccm_setkey() or
* mbedtls_ccm_free().
*
* \param ctx CCM context to initialize
*/
void mbedtls_ccm_init( mbedtls_ccm_context *ctx );
/**
* \brief CCM initialization (encryption and decryption)
*
* \param ctx CCM context to be initialized
* \param cipher cipher to use (a 128-bit block cipher)
* \param key encryption key
* \param keybits key size in bits (must be acceptable by the cipher)
*
* \return 0 if successful, 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 Free a CCM context and underlying cipher sub-context
*
* \param ctx CCM context to free
*/
void mbedtls_ccm_free( mbedtls_ccm_context *ctx );
/**
* \brief CCM buffer encryption
*
* \param ctx CCM context
* \param length length of the input data in bytes
* \param iv nonce (initialization vector)
* \param iv_len length of IV in bytes
* must be 2, 3, 4, 5, 6, 7 or 8
* \param add additional data
* \param add_len length of additional data in bytes
* must be less than 2^16 - 2^8
* \param input buffer holding the input data
* \param output buffer for holding the output data
* must be at least 'length' bytes wide
* \param tag buffer for holding the tag
* \param tag_len length of the tag to generate in bytes
* must be 4, 6, 8, 10, 14 or 16
*
* \note The tag is written to a separate buffer. To get the tag
* concatenated with the output as in the CCM spec, use
* tag = output + length and make sure the output buffer is
* at least length + tag_len wide.
*
* \return 0 if successful
*/
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 CCM buffer authenticated decryption
*
* \param ctx CCM context
* \param length length of the input data
* \param iv initialization vector
* \param iv_len length of IV
* \param add additional data
* \param add_len length of additional data
* \param input buffer holding the input data
* \param output buffer for holding the output data
* \param tag buffer holding the tag
* \param tag_len length of the tag
*
* \return 0 if successful and authenticated,
* MBEDTLS_ERR_CCM_AUTH_FAILED if 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 );
#if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_AES_C)
/**
* \brief Checkup routine
*
* \return 0 if successful, or 1 if the test failed
*/
int mbedtls_ccm_self_test( int verbose );
#endif /* MBEDTLS_SELF_TEST && MBEDTLS_AES_C */
#ifdef __cplusplus
}
#endif
#endif /* MBEDTLS_CCM_H */