mbed-os/nanostack/ccmLIB.h

119 lines
4.6 KiB
C

/*
* Copyright (c) 2014-2018, Pelion and affiliates.
* 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.
*/
#ifndef CCMLIB_H_
#define CCMLIB_H_
#include "ns_types.h"
#include "platform/arm_hal_aes.h"
/**
*
* \file ccmLIB.h
* \brief CCM Library API.
*
* \section ccm-api CCM Library API:
* - ccm_sec_init(), A function to init CCM context.
* - ccm_process_run(), A function to run configured CCM process.
*
* \section ccm-instruction CCM process sequence:
* 1. Init CCM context by, ccm key, ccm_sec_init()
* - security level
* - 128-bit CCM key
* - mode: AES_CCM_ENCRYPT or AES_CCM_DECRYPT
* - CCM L parameter: 2 or 3 depending on the nonce length (802.15.4 use 2 and TLS security use 3)
* 2. Define ADATA pointer and length, if returned global structure mic_len field is > 0
* 3. Set data pointer and length
* 4. Do configured CCM process ccm_process_run()
* 5. Check return value:
* -If 0 Process ok
* -< 0 MIC fail or parameter fail
*
*/
#ifdef __cplusplus
extern "C" {
#endif
#define AES_NO_SECURITY 0x00 /**< No security */
#define AES_SECURITY_LEVEL_MIC32 0x01 /**< MIC32 */
#define AES_SECURITY_LEVEL_MIC64 0x02 /**< MIC64 */
#define AES_SECURITY_LEVEL_MIC128 0x03 /**< MIC128 */
#define AES_SECURITY_LEVEL_ENC 0x04 /**< ENC */
#define AES_SECURITY_LEVEL_ENC_MIC32 0x05 /**< ENC_MIC32 */
#define AES_SECURITY_LEVEL_ENC_MIC64 0x06 /**< ENC_MIC64 */
#define AES_SECURITY_LEVEL_ENC_MIC128 0x07 /**< ENC_MIC128 */
#define AES_CCM_ENCRYPT 0x00 /**< Encryption mode */
#define AES_CCM_DECRYPT 0x01 /**< Decryption mode */
/*!
* \struct ccm_globals_t
* \brief CCM global structure.
* The structure is used for configuring NONCE, adata and data before calling ccm_process_run().
*/
typedef struct {
uint8_t exp_nonce[15]; /**< CCM NONCE buffer Nonce. */
uint8_t *data_ptr; /**< Pointer to data IN. */
uint16_t data_len; /**< Length of data IN. */
const uint8_t *adata_ptr; /**< Pointer to authentication data. */
uint16_t adata_len; /**< Length of authentication data. */
unsigned ccm_encode_mode: 1; /**< Encryption modeAES_CCM_ENCRYPT or AES_CCM_DECRYPT. */
unsigned ccm_sec_level: 3; /**< Encryption operation security level 0-7. */
unsigned ccm_l_param: 4; /**< Can be 2 or 3. 2 when NONCE length is 13 and 3 when 12*/
uint8_t mic_len; /**< ccm_sec_init() sets here the length of MIC. */
uint8_t *mic; /**< Encrypt process writes MIC. Decrypt reads it and compares it with the MIC obtained from data. */
const uint8_t *key_ptr; /**< Encyption key pointer to 128-bit key. */
arm_aes_context_t *aes_context; /**< Allocated AES context. */
} ccm_globals_t;
/**
* \brief A function to initialize the CCM context.
* \param ccm_context pointer to initialized XXM context
* \param sec_level Used CCM security level (0-7).
* \param ccm_key Pointer to 128-key.
* \param mode AES_CCM_ENCRYPT or AES_CCM_DECRYPT.
* \param ccm_l Can be 2 or 3. 2 when NONCE length is 13 and 3 when 12. (NONCE length = (15-ccm_l))
*
* \return true when AES context allocation is OK and given parameters.
* \return false CCM parameters or AES context allocation fail.
*/
extern bool ccm_sec_init(ccm_globals_t *ccm_context, uint8_t sec_level, const uint8_t *ccm_key, uint8_t mode, uint8_t ccm_l);
/**
* \brief A function to run the configured CCM process.
* When AES_CCM_ENCRYPT mode is selected and MIC is needed, the library saves MIC right after the encrypted data.
* \param ccm_params CCM parameters
*
* \return 0 CCM process OK and when AES_CCM_DECRYPT mode was selected also MIC was correct.
* \return -1 Init not called or data or adata pointers or lengths are zero.
* \return -2 Null pointer given to function.
*/
extern int8_t ccm_process_run(ccm_globals_t *ccm_params);
/**
* \brief A function to free aes context. Call only if ccm_process_run() is not called
* \param ccm_params CCM parameters
*
*/
extern void ccm_free(ccm_globals_t *ccm_params);
#ifdef __cplusplus
}
#endif
#endif /* CCMLIB_H_ */