Hello. All
I'm using STM32L151 MCU, stm32 crypto library v.3.0.0.
I implemented CMAC according to the sample code but it returned "AES_ERR_BAD_CONTEXT".
I could not find any reason.. please let me know to solve this problem.!!
Here is my code for CMAC encryption.
static AESCMACctx_stt AEScmacCtx = { 0 };
// Static function declarations -----------------------
// Static function definitions ------------------------
static int32_t AesCmacInit( uint8_t * key )
{
int32_t result = AES_SUCCESS;
AEScmacCtx.mFlags = E_SK_DEFAULT; // 0x00000000
AEScmacCtx.mKeySize = CRL_AES128_KEY; // 16
AEScmacCtx.pmKey = key;
AEScmacCtx.mTagSize = CRL_AES_BLOCK; // 16
result = AES_CMAC_Encrypt_Init(&AEScmacCtx);
return result;
}
// Module interface function definitions --------------
int32_t AesCmacEncrypt( uint8_t * plainData, int32_t plainSize, uint8_t * key, uint8_t * cmacData, int32_t * cmacSize )
{
int32_t result = AES_SUCCESS;
result = AesCmacInit( key );
if( result != AES_SUCCESS )
{
return result
}
AEScmacCtx.mFlags |= E_SK_FINAL_APPEND; // 0x00000020
result = AES_CMAC_Encrypt_Append(&AEScmacCtx, plainData, plainSize );
if( result != AES_SUCCESS )
{
return result;
}
result = AES_CMAC_Encrypt_Finish(&AEScmacCtx, cmacData, cmacSize);
if( result != AES_SUCCESS) // <- always return AES_ERR_BAD_CONTEXT
{
return result;
}
return result;
}
