/**
* \file ccm.h
*
* \brief This file provides an API for the CCM authenticated encryption
* mode for block ciphers.
*
* 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>
*
* Definition of CCM:
* http://csrc.nist.gov/publications/nistpubs/800-38C/SP800-38C_updated-July20_2007.pdf
* RFC 3610 "Counter with CBC-MAC (CCM)"
*
* Related:
* RFC 5116 "An Interface and Algorithms for Authenticated Encryption"
*
* Definition of CCM*:
* IEEE 802.15.4 - IEEE Standard for Local and metropolitan area networks
* Integer representation is fixed most-significant-octet-first order and
* the representation of octets is most-significant-bit-first order. This is
* consistent with RFC 3610.
*/
/*
* Copyright (C) 2006-2018, Arm Limited (or its affiliates), All Rights Reserved
* SPDX-License-Identifier: GPL-2.0
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* 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. */
/* MBEDTLS_ERR_CCM_HW_ACCEL_FAILED is deprecated and should not be used. */
#define MBEDTLS_ERR_CCM_HW_ACCEL_FAILED -0x0011 /**< CCM hardware accelerator failed. */
#ifdef __cplusplus
extern "C" {
#endif
#if !defined(MBEDTLS_CCM_ALT)
// Regular implementation
//
/**
* \brief The CCM context-type definition. The CCM context is passed
* to the APIs called.
*/
typedef struct mbedtls_ccm_context
{
mbedtls_cipher_context_t cipher_ctx; /*!< The cipher context used. */
}
mbedtls_ccm_context;
#else /* MBEDTLS_CCM_ALT */
#include "ccm_alt.h"
#endif /* MBEDTLS_CCM_ALT */
/**
* \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. This must not be \c NULL.
*/
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. This must be an initialized
* context.
* \param cipher The 128-bit block cipher to use.
* \param key The encryption key. This must not be \c NULL.
* \param keybits The key size in bits. This must be acceptable by the cipher.
*
* \return \c 0 on success.
* \return A CCM or cipher-specific error code on failure.
*/
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. If this is \c NULL, the function
* has no effect. Otherwise, this must be initialized.
*/
void mbedtls_ccm_free( mbedtls_ccm_context *ctx );
/**
* \brief This function encrypts a buffer using CCM.
*
* \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.
*
* \param ctx The CCM context to use for encryption. This must be
* initialized and bound to a key.
* \param length The length of the input data in Bytes.
* \param iv The initialization vector (nonce). This must be a readable
* buffer of at least \p iv_len Bytes.
* \param iv_len The length of the nonce in Bytes: 7, 8, 9, 10, 11, 12,
* or 13. The length L of the message length field is
* 15 - \p iv_len.
* \param add The additional data field. If \p add_len is greater than
* zero, \p add must be a readable buffer of at least that
* length.
* \param add_len The length of additional data in Bytes.
* This must be less than `2^16 - 2^8`.
* \param input The buffer holding the input data. If \p length is greater
* than zero, \p input must be a readable buffer of at least
* that length.
* \param output The buffer holding the output data. If \p length is greater
* than zero, \p output must be a writable buffer of at least
* that length.
* \param tag The buffer holding the authentication field. This must be a
* readable buffer of at least \p tag_len Bytes.
* \param tag_len The length of the authentication field to generate in Bytes:
* 4, 6, 8, 10, 12, 14 or 16.
*
* \return \c 0 on success.
* \return A CCM or cipher-specific error code on failure.
*/
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 encrypts a buffer using CCM*.
*
* \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.
*
* \note When using this function in a variable tag length context,
* the tag length has to be encoded into the \p iv passed to
* this function.
*
* \param ctx The CCM context to use for encryption. This must be
* initialized and bound to a key.
* \param length The length of the input data in Bytes.
* \param iv The initialization vector (nonce). This must be a readable
* buffer of at least \p iv_len Bytes.
* \param iv_len The length of the nonce in Bytes: 7, 8, 9, 10, 11, 12,
* or 13. The length L of the message length field is
* 15 - \p iv_len.
* \param add The additional data field. This must be a readable buffer of
* at least \p add_len Bytes.
* \param add_len The length of additional data in Bytes.
* This must be less than 2^16 - 2^8.
* \param input The buffer holding the input data. If \p length is greater
* than zero, \p input must be a readable buffer of at least
* that length.
* \param output The buffer holding the output data. If \p length is greater
* than zero, \p output must be a writable buffer of at least
* that length.
* \param tag The buffer holding the authentication field. This must be a
* readable buffer of at least \p tag_len Bytes.
* \param tag_len The length of the authentication field to generate in Bytes:
* 0, 4, 6, 8, 10, 12, 14 or 16.
*
* \warning Passing \c 0 as \p tag_len means that the message is no
* longer authenticated.
*
* \return \c 0 on success.
* \return A CCM or cipher-specific error code on failure.
*/
int mbedtls_ccm_star_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. This must be
* initialized and bound to a key.
* \param length The length of the input data in Bytes.
* \param iv The initialization vector (nonce). This must be a readable
* buffer of at least \p iv_len Bytes.
* \param iv_len The length of the nonce in Bytes: 7, 8, 9, 10, 11, 12,
* or 13. The length L of the message length field is
* 15 - \p iv_len.
* \param add The additional data field. This must be a readable buffer
* of at least that \p add_len Bytes..
* \param add_len The length of additional data in Bytes.
* This must be less than 2^16 - 2^8.
* \param input The buffer holding the input data. If \p length is greater
* than zero, \p input must be a readable buffer of at least
* that length.
* \param output The buffer holding the output data. If \p length is greater
* than zero, \p output must be a writable buffer of at least
* that length.
* \param tag The buffer holding the authentication field. This must be a
* readable buffer of at least \p tag_len Bytes.
* \param tag_len The length of the authentication field to generate in Bytes:
* 4, 6, 8, 10, 12, 14 or 16.
*
* \return \c 0 on success. This indicates that the message is authentic.
* \return #MBEDTLS_ERR_CCM_AUTH_FAILED if the tag does not match.
* \return A cipher-specific error code on calculation failure.
*/
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 );
/**
* \brief This function performs a CCM* authenticated decryption of a
* buffer.
*
* \note When using this function in a variable tag length context,
* the tag length has to be decoded from \p iv and passed to
* this function as \p tag_len. (\p tag needs to be adjusted
* accordingly.)
*
* \param ctx The CCM context to use for decryption. This must be
* initialized and bound to a key.
* \param length The length of the input data in Bytes.
* \param iv The initialization vector (nonce). This must be a readable
* buffer of at least \p iv_len Bytes.
* \param iv_len The length of the nonce in Bytes: 7, 8, 9, 10, 11, 12,
* or 13. The length L of the message length field is
* 15 - \p iv_len.
* \param add The additional data field. This must be a readable buffer of
* at least that \p add_len Bytes.
* \param add_len The length of additional data in Bytes.
* This must be less than 2^16 - 2^8.
* \param input The buffer holding the input data. If \p length is greater
* than zero, \p input must be a readable buffer of at least
* that length.
* \param output The buffer holding the output data. If \p length is greater
* than zero, \p output must be a writable buffer of at least
* that length.
* \param tag The buffer holding the authentication field. This must be a
* readable buffer of at least \p tag_len Bytes.
* \param tag_len The length of the authentication field in Bytes.
* 0, 4, 6, 8, 10, 12, 14 or 16.
*
* \warning Passing \c 0 as \p tag_len means that the message is nos
* longer authenticated.
*
* \return \c 0 on success.
* \return #MBEDTLS_ERR_CCM_AUTH_FAILED if the tag does not match.
* \return A cipher-specific error code on calculation failure.
*/
int mbedtls_ccm_star_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 The CCM checkup routine.
*
* \return \c 0 on success.
* \return \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 */