Accelerated AES-CMAC Cipher
Cryptography Hardware Acceleration Plugins > Silicon Labs Cryptography Hardware Acceleration Plugins for mbed TLS

Detailed Description

Accelerated AES-CMAC cipher for the mbed TLS API using the CRYPTOACC or SE peripheral. This implementation builds on the PSA Crypto drivers (Silicon Labs Cryptography Hardware Acceleration Plugins for PSA Crypto).

Data Structures

struct  mbedtls_cmac_context_t
 

Macros

#define SL_MAC_OPERATION_CTX_TYPE   sli_se_transparent_mac_operation_t
 

Functions

int mbedtls_cipher_cmac_starts (mbedtls_cipher_context_t *ctx, const unsigned char *key, size_t keybits)
 This function sets the CMAC key, and prepares to authenticate the input data. Must be called with an initialized cipher context.
 
int mbedtls_cipher_cmac_update (mbedtls_cipher_context_t *ctx, const unsigned char *input, size_t ilen)
 This function feeds an input buffer into an ongoing CMAC computation.
 
int mbedtls_cipher_cmac_finish (mbedtls_cipher_context_t *ctx, unsigned char *output)
 This function finishes the CMAC operation, and writes the result to the output buffer.
 
int mbedtls_cipher_cmac_reset (mbedtls_cipher_context_t *ctx)
 This function prepares the authentication of another message with the same key as the previous CMAC operation.
 
int mbedtls_cipher_cmac (const mbedtls_cipher_info_t *cipher_info, const unsigned char *key, size_t keylen, const unsigned char *input, size_t ilen, unsigned char *output)
 This function calculates the full generic CMAC on the input buffer with the provided key.
 
int mbedtls_aes_cmac_prf_128 (const unsigned char *key, size_t key_len, const unsigned char *input, size_t in_len, unsigned char output[16])
 This function implements the AES-CMAC-PRF-128 pseudorandom function, as defined in RFC-4615: The Advanced Encryption Standard-Cipher-based Message Authentication Code-Pseudo-Random Function-128 (AES-CMAC-PRF-128) Algorithm for the Internet Key Exchange Protocol (IKE).
 

Macro Definition Documentation

#define SL_MAC_OPERATION_CTX_TYPE   sli_se_transparent_mac_operation_t

Definition at line 56 of file cmac_alt.h.

Function Documentation

int mbedtls_aes_cmac_prf_128 ( const unsigned char *  key,
size_t  key_len,
const unsigned char *  input,
size_t  in_len,
unsigned char  output[16] 
)

This function implements the AES-CMAC-PRF-128 pseudorandom function, as defined in RFC-4615: The Advanced Encryption Standard-Cipher-based Message Authentication Code-Pseudo-Random Function-128 (AES-CMAC-PRF-128) Algorithm for the Internet Key Exchange Protocol (IKE).

Parameters
keyThe key to use.
key_lenThe key length in Bytes.
inputThe buffer holding the input data.
in_lenThe length of the input data in Bytes.
outputThe buffer holding the generated 16 Bytes of pseudorandom output.
Returns
0 on success.
int mbedtls_cipher_cmac ( const mbedtls_cipher_info_t *  cipher_info,
const unsigned char *  key,
size_t  keylen,
const unsigned char *  input,
size_t  ilen,
unsigned char *  output 
)

This function calculates the full generic CMAC on the input buffer with the provided key.

The function allocates the context, performs the calculation, and frees the context.

The CMAC result is calculated as output = generic CMAC(cmac key, input buffer).

Parameters
cipher_infoThe cipher information.
keyThe CMAC key.
keylenThe length of the CMAC key in bits.
inputThe buffer holding the input data.
ilenThe length of the input data.
outputThe buffer for the generic CMAC result.
Returns
0 on success, or MBEDTLS_ERR_MD_BAD_INPUT_DATA if parameter verification fails.
int mbedtls_cipher_cmac_finish ( mbedtls_cipher_context_t *  ctx,
unsigned char *  output 
)

This function finishes the CMAC operation, and writes the result to the output buffer.

It is called after mbedtls_cipher_cmac_update(). It can be followed by mbedtls_cipher_cmac_reset() and mbedtls_cipher_cmac_update(), or mbedtls_cipher_free().

Parameters
ctxThe cipher context used for the CMAC operation.
outputThe output buffer for the CMAC checksum result.
Returns
0 on success, or MBEDTLS_ERR_MD_BAD_INPUT_DATA if parameter verification fails.
int mbedtls_cipher_cmac_reset ( mbedtls_cipher_context_t *  ctx)

This function prepares the authentication of another message with the same key as the previous CMAC operation.

It is called after mbedtls_cipher_cmac_finish() and before mbedtls_cipher_cmac_update().

Parameters
ctxThe cipher context used for the CMAC operation.
Returns
0 on success, or MBEDTLS_ERR_MD_BAD_INPUT_DATA if parameter verification fails.
int mbedtls_cipher_cmac_starts ( mbedtls_cipher_context_t *  ctx,
const unsigned char *  key,
size_t  keybits 
)

This function sets the CMAC key, and prepares to authenticate the input data. Must be called with an initialized cipher context.

Parameters
ctxThe cipher context used for the CMAC operation, initialized as one of the following types:
  • MBEDTLS_CIPHER_AES_128_ECB
  • MBEDTLS_CIPHER_AES_192_ECB
  • MBEDTLS_CIPHER_AES_256_ECB
  • MBEDTLS_CIPHER_DES_EDE3_ECB
keyThe CMAC key.
keybitsThe length of the CMAC key in bits. Must be supported by the cipher.
Returns
0 on success, or a cipher-specific error code.
int mbedtls_cipher_cmac_update ( mbedtls_cipher_context_t *  ctx,
const unsigned char *  input,
size_t  ilen 
)

This function feeds an input buffer into an ongoing CMAC computation.

It is called between mbedtls_cipher_cmac_starts() or mbedtls_cipher_cmac_reset(), and mbedtls_cipher_cmac_finish(). Can be called repeatedly.

Parameters
ctxThe cipher context used for the CMAC operation.
inputThe buffer holding the input data.
ilenThe length of the input data.
Returns
0 on success, or MBEDTLS_ERR_MD_BAD_INPUT_DATA if parameter verification fails.