mcuxCsslMemory_Clear_example.c

Example constant-time memory clear (CSSL component mcuxCsslMemory).

Example constant-time memory clear (CSSL component mcuxCsslMemory)

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/* Copyright 2023, 2025 NXP                                                 */
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#include <mcuxClToolchain.h>
#include <mcuxCsslMemory.h>
#include <mcuxCsslMemory_Examples.h>
#include <mcuxCsslFlowProtection.h>
#include <mcuxCsslFlowProtection_FunctionIdentifiers.h>
#include <mcuxCsslParamIntegrity.h>
 
MCUXCSSL_MEMORY_EX_FUNCTION(mcuxCsslMemory_Clear_example)
{
  /* Define data array */
  ALIGNED uint8_t arr[] = {0xe4u, 0xf9u, 0x26u, 0x4cu, 0x65u, 0xe2u, 0x13u, 0xa3u,
                           0x9au, 0x40u, 0xd7u, 0x87u, 0xccu, 0x0bu, 0x31u, 0x18u,
                           0xacu, 0x55u, 0xb5u, 0x7du, 0x06u, 0x7fu, 0xceu, 0xe4u,
                           0xb2u, 0x7eu, 0xd5u, 0xaau, 0x90u, 0x9au, 0x42u, 0x56u,
                           0x76u};
 
  /* Clear whole array => should return success */
  MCUX_CSSL_FP_FUNCTION_CALL_BEGIN(clearResult, clearToken, mcuxCsslMemory_Clear(
  /*  mcuxCsslParamIntegrity_Checksum_t chk */ MCUX_CSSL_PI_PROTECT(arr, sizeof(arr), sizeof(arr)),
  /*  void * pDst                          */ arr,
  /*  uint32_t dstLength                   */ sizeof(arr),
  /*  uint32_t length                      */ sizeof(arr)
  ));
 
  /* Check the return code of mcuxCsslMemory_Clear */
  if((MCUX_CSSL_FP_FUNCTION_CALLED(mcuxCsslMemory_Clear) != clearToken) || (MCUXCSSLMEMORY_STATUS_OK != clearResult))
  {
    return MCUXCSSLMEMORY_EX_ERROR;
  }
 
  MCUX_CSSL_FP_FUNCTION_CALL_END();
 
 
  return MCUXCSSLMEMORY_EX_OK;
}