MCUX CLNS MCUX Crypto Library Normal Secure |

Functions
mcuxClMac_Functions
mcuxClMac

Defines all functions of mcuxClMac. More...

## Functions

mcuxClMac_Status_Protected_t | mcuxClMac_compute (mcuxClSession_Handle_t session, const mcuxClKey_Handle_t key, const mcuxClMac_Mode_t mode, const uint8_t *const in, uint32_t inSize, uint8_t *const mac)
| One-shot message authentication code (MAC) computation. More...
mcuxClMac_Status_Protected_t | mcuxClMac_init (mcuxClSession_Handle_t session, mcuxClMac_Context_t *const context, const mcuxClKey_Handle_t key, const mcuxClMac_Mode_t mode)
| Initialization for a multipart MAC computation. More...
mcuxClMac_Status_Protected_t | mcuxClMac_process (mcuxClSession_Handle_t session, mcuxClMac_Context_t *const context, const uint8_t *const in, uint32_t inSize)
| Data processing for a multipart MAC computation. More...
mcuxClMac_Status_Protected_t | mcuxClMac_finish (mcuxClSession_Handle_t session, mcuxClMac_Context_t *const context, uint8_t *const mac)
| MAC generation for a multipart MAC computation. More...

## Detailed Description

Defines all functions of mcuxClMac.

## Function Documentation

## ◆ mcuxClMac_compute()

mcuxClMac_Status_Protected_t mcuxClMac_compute | ( | mcuxClSession_Handle_t | session,
|  | const mcuxClKey_Handle_t | key,
|  | const mcuxClMac_Mode_t | mode,
|  | const uint8_t *const | in,
|  | uint32_t | inSize,
|  | uint8_t *const | mac
| ) |  |

One-shot message authentication code (MAC) computation.

This function performs a MAC computation in one shot. The algorithm to be used will be determined based on the key that is provided.

For example, to perform an AES MAC computation with a 128-bit key in CMAC mode on padded data, the following needs to be provided:

- AES128 key
- CMAC mode
- Input data, size must be a multiple of the AES block size
- Output data buffer, at least the size of a single AES block

If the selected mode `mode` is HMAC, i.e. mcuxClMac_Mode_HMAC_SHA2_256, the input buffer `in` will be modified by applying padding to it. The caller must ensure that the input buffer is large enough by determining its size using MCUXCLMAC_GET_HMAC_INPUTBUFFER_LENGTH on the data size `inSize`.

Also note that HMAC only works with keys loaded into coprocessor (see mcuxClKey for details).

Parameters

  [in] | session |
  [in] | key | Key to be used to authenticate the data.
  [in] | mode | Mode that should be used during the MAC operation.
  [in] | in | Pointer to the input buffer that contains the data that needs to be authenticated.
  [in] | inSize | Number of bytes of data in the `in` buffer.
  [out] | mac | Pointer to the output buffer where the MAC needs to be written.

Returns
  A code-flow protected error code (see Flow Protection API)

Return values

  MCUXCLMAC_ERRORCODE_OK | Mac operation successful
  MCUXCLMAC_ERRORCODE_ERROR | Error occurred during Mac operation

Examples
  mcuxClMac_cmac_oneshot_example.c.

## ◆ mcuxClMac_init()

mcuxClMac_Status_Protected_t mcuxClMac_init | ( | mcuxClSession_Handle_t | session,
|  | mcuxClMac_Context_t *const | context,
|  | const mcuxClKey_Handle_t | key,
|  | const mcuxClMac_Mode_t | mode
| ) |  |

Initialization for a multipart MAC computation.

This function performs the initialization of a context for a multipart MAC computation. The algorithm to be used will be determined based on the key that is provided.

This function should only be called once, as the first step for a multipart computation.

For example, to perform a multipart AES MAC computation with a 128-bit key in CMAC mode on padded data, the following needs to be provided in this step:

- AES128 key
- CMAC mode

The size of the context depends on the mode used (see mcuxClMac_MemoryConsumption).

See also
  mcuxClMac_process
  mcuxClMac_finish

Parameters

  [in] | session |
  [in] | context |
  [in] | key | Key to be used to MAC the data.
  [in] | mode | Mode that should be used during the MAC operation.

Returns
  Status of the context initialization.

## ◆ mcuxClMac_process()

mcuxClMac_Status_Protected_t mcuxClMac_process | ( | mcuxClSession_Handle_t | session,
|  | mcuxClMac_Context_t *const | context,
|  | const uint8_t *const | in,
|  | uint32_t | inSize
| ) |  |

Data processing for a multipart MAC computation.

This function performs the data processing for a multipart MAC computation.

This function can be called multiple times, after the multipart context initialization.

For example, to perform a multipart AES MAC computation with a 128-bit key in CMAC mode on padded data, the following needs to be provided in this step:

- Input data, size must be a multiple of the AES block size

The size of the context depends on the mode used (see mcuxClMac_MemoryConsumption).

See also
  mcuxClMac_init
  mcuxClMac_finish

Parameters

  [in] | session |
  [in] | context |
  [in] | in | Pointer to the input buffer that contains the data that need to be processed.
  [in] | inSize | Number of bytes of data in the `in` buffer.

Returns
  A code-flow protected error code (see Flow Protection API)

Return values

  MCUXCLMAC_ERRORCODE_OK | Mac operation successful
  MCUXCLMAC_ERRORCODE_ERROR | Error occurred during Mac operation

## ◆ mcuxClMac_finish()

mcuxClMac_Status_Protected_t mcuxClMac_finish | ( | mcuxClSession_Handle_t | session,
|  | mcuxClMac_Context_t *const | context,
|  | uint8_t *const | mac
| ) |  |

MAC generation for a multipart MAC computation.

This function performs the final MAC generation step for a multipart MAC computation.

This function should only be called once, as the last step for a multipart computation.

For example, to perform a multipart AES MAC computation with a 128-bit key in CMAC mode on padded data, the following needs to be provided in this step:

- Output data buffer, at least the size of a single AES block

The size of the context depends on the mode used (see mcuxClMac_MemoryConsumption).

See also
  mcuxClMac_init
  mcuxClMac_process

Parameters

  [in] | session |
  [in] | context |
  [out] | mac | Pointer to the output buffer where the MAC needs to be written.

Returns
  A code-flow protected error code (see Flow Protection API)

Return values

  MCUXCLMAC_ERRORCODE_OK | Mac operation successful
  MCUXCLMAC_ERRORCODE_ERROR | Error occurred during Mac operation