ccm_alt.h

00001 /*
00002  *  ccm_alt.h
00003  *
00004  *  Copyright (C) 2018, Arm Limited, All Rights Reserved
00005  *  SPDX-License-Identifier: Apache-2.0
00006  *
00007  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
00008  *  not use this file except in compliance with the License.
00009  *  You may obtain a copy of the License at
00010  *
00011  *  http://www.apache.org/licenses/LICENSE-2.0
00012  *
00013  *  Unless required by applicable law or agreed to in writing, software
00014  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
00015  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00016  *  See the License for the specific language governing permissions and
00017  *  limitations under the License.
00018  *
00019  */
00020 
00021 #ifndef __CCM_ALT__
00022 #define __CCM_ALT__
00023 
00024 #if defined(MBEDTLS_CCM_ALT)
00025 #include "crys_aesccm.h"
00026 
00027 #ifdef __cplusplus
00028 extern "C" {
00029 #endif
00030 
00031 typedef struct {
00032     CRYS_AESCCM_Key_t  cipher_key ;    /*!< cipher key used */
00033     CRYS_AESCCM_KeySize_t  keySize_ID;
00034 }
00035 mbedtls_ccm_context;
00036 
00037 /**
00038  * \brief           Initialize CCM context (just makes references valid)
00039  *                  Makes the context ready for mbedtls_ccm_setkey() or
00040  *                  mbedtls_ccm_free().
00041  *
00042  * \param ctx       CCM context to initialize
00043  */
00044 void mbedtls_ccm_init( mbedtls_ccm_context *ctx );
00045 
00046 /**
00047  * \brief           CCM initialization (encryption and decryption)
00048  *
00049  * \param ctx       CCM context to be initialized
00050  * \param cipher    cipher to use (a 128-bit block cipher)
00051  * \param key       encryption key
00052  * \param keybits   key size in bits (must be acceptable by the cipher)
00053  *
00054  * \return          0 if successful, or a cipher specific error code
00055  */
00056 int mbedtls_ccm_setkey( mbedtls_ccm_context *ctx,
00057                         mbedtls_cipher_id_t cipher,
00058                         const unsigned char *key,
00059                         unsigned int keybits );
00060 
00061 /**
00062  * \brief           Free a CCM context and underlying cipher sub-context
00063  *
00064  * \param ctx       CCM context to free
00065  */
00066 void mbedtls_ccm_free( mbedtls_ccm_context *ctx );
00067 
00068 /**
00069  * \brief           CCM buffer encryption
00070  *
00071  * \param ctx       CCM context
00072  * \param length    length of the input data in bytes
00073  * \param iv        nonce (initialization vector)
00074  * \param iv_len    length of IV in bytes
00075  *                  must be 2, 3, 4, 5, 6, 7 or 8
00076  * \param add       additional data
00077  * \param add_len   length of additional data in bytes
00078  *                  must be less than 2^16 - 2^8
00079  * \param input     buffer holding the input data
00080  * \param output    buffer for holding the output data
00081  *                  must be at least 'length' bytes wide
00082  * \param tag       buffer for holding the tag
00083  * \param tag_len   length of the tag to generate in bytes
00084  *                  must be 4, 6, 8, 10, 14 or 16
00085  *
00086  * \note            The tag is written to a separate buffer. To get the tag
00087  *                  concatenated with the output as in the CCM spec, use
00088  *                  tag = output + length and make sure the output buffer is
00089  *                  at least length + tag_len wide.
00090  *
00091  * \return          0 if successful
00092  */
00093 int mbedtls_ccm_encrypt_and_tag( mbedtls_ccm_context *ctx, size_t length,
00094                          const unsigned char *iv, size_t iv_len,
00095                          const unsigned char *add, size_t add_len,
00096                          const unsigned char *input, unsigned char *output,
00097                          unsigned char *tag, size_t tag_len );
00098 
00099 /**
00100  * \brief           CCM buffer authenticated decryption
00101  *
00102  * \param ctx       CCM context
00103  * \param length    length of the input data
00104  * \param iv        initialization vector
00105  * \param iv_len    length of IV
00106  * \param add       additional data
00107  * \param add_len   length of additional data
00108  * \param input     buffer holding the input data
00109  * \param output    buffer for holding the output data
00110  * \param tag       buffer holding the tag
00111  * \param tag_len   length of the tag
00112  *
00113  * \return         0 if successful and authenticated,
00114  *                 MBEDTLS_ERR_CCM_AUTH_FAILED if tag does not match
00115  */
00116 int mbedtls_ccm_auth_decrypt( mbedtls_ccm_context *ctx, size_t length,
00117                       const unsigned char *iv, size_t iv_len,
00118                       const unsigned char *add, size_t add_len,
00119                       const unsigned char *input, unsigned char *output,
00120                       const unsigned char *tag, size_t tag_len );
00121 
00122 #ifdef __cplusplus
00123 }
00124 #endif
00125 
00126 #endif /* MBEDTLS_CCM_ALT */
00127 #endif /* __CCM_ALT__ */