/**
* @brief Encrypt using AES in ECB Mode
* @param Key: Key used for AES algorithm.
* @param Input: pointer to the Input buffer.
* @param Ilength: length of the Input buffer, must be a multiple of 16 bytes.
* @param Output: pointer to the returned buffer.
* @retval An ErrorStatus enumeration value:
* - SUCCESS: Operation done
* - ERROR: Operation failed
*/
ErrorStatus AES_ECB_Encrypt(uint8_t * Key, uint8_t * Input, uint32_t Ilength,
uint8_t * Output)
{
AES_InitTypeDef AES_InitStructure;
AES_KeyInitTypeDef AES_KeyInitStructure;
ErrorStatus status = SUCCESS;
uint32_t keyaddr = (uint32_t) Key;
uint32_t inputaddr = (uint32_t) Input;
uint32_t outputaddr = (uint32_t) Output;
__IO uint32_t counter = 0;
uint32_t ccstatus = 0;
uint32_t i = 0;
/* AES Key initialisation */
AES_KeyInitStructure.AES_Key3 = __REV(*(uint32_t *) (keyaddr));
keyaddr += 4;
AES_KeyInitStructure.AES_Key2 = __REV(*(uint32_t *) (keyaddr));
keyaddr += 4;
AES_KeyInitStructure.AES_Key1 = __REV(*(uint32_t *) (keyaddr));
keyaddr += 4;
AES_KeyInitStructure.AES_Key0 = __REV(*(uint32_t *) (keyaddr));
AES_KeyInit(&AES_KeyInitStructure);
/* AES configuration */
AES_InitStructure.AES_Operation = AES_Operation_Encryp;
AES_InitStructure.AES_Chaining = AES_Chaining_ECB;
AES_InitStructure.AES_DataType = AES_DataType_8b;
AES_Init(&AES_InitStructure);
/* Enable AES */
AES_Cmd(ENABLE);
for (i = 0; ((i < Ilength) && (status != ERROR)); i += 16) {
AES_WriteSubData(*(uint32_t *) (inputaddr));
inputaddr += 4;
AES_WriteSubData(*(uint32_t *) (inputaddr));
inputaddr += 4;
AES_WriteSubData(*(uint32_t *) (inputaddr));
inputaddr += 4;
AES_WriteSubData(*(uint32_t *) (inputaddr));
inputaddr += 4;
/* Wait for CCF flag to be set */
counter = 0;
do {
ccstatus = AES_GetFlagStatus(AES_FLAG_CCF);
counter++;
} while ((counter != AES_CC_TIMEOUT) && (ccstatus == RESET));
if (ccstatus == RESET) {
status = ERROR;
} else {
/* Clear CCF flag */
AES_ClearFlag(AES_FLAG_CCF);
/* Read cipher text */
*(uint32_t *) (outputaddr) = AES_ReadSubData();
outputaddr += 4;
*(uint32_t *) (outputaddr) = AES_ReadSubData();
outputaddr += 4;
*(uint32_t *) (outputaddr) = AES_ReadSubData();
outputaddr += 4;
*(uint32_t *) (outputaddr) = AES_ReadSubData();
outputaddr += 4;
}
}
/* Disable AES before starting new processing */
AES_Cmd(DISABLE);
return status;
}
/**
* @brief Main program.
* @param None
* @retval None
*/
void main(void)
{
uint8_t arrayindex = 0;
ErrorStatus cryptostatus = ERROR;
/* Enable AES clock */
CLK_PeripheralClockConfig(CLK_Peripheral_AES, ENABLE);
/* Initialize LEDs mounted on STM8L1528-EVAL board */
STM_EVAL_LEDInit(LED1);
STM_EVAL_LEDInit(LED3);
/* Select the encryption mode */
AES_OperationModeConfig(AES_Operation_Encryp);
/* Enable the AES peripheral */
AES_Cmd(ENABLE);
/* write 32 times in the DINR register with encryption key and plain text */
while (arrayindex < 16)
{
/* writing MSB first */
AES_WriteSubKey(EncryptionKey[arrayindex]);
AES_WriteSubData(PlainText[arrayindex]);
/* Increment arrayindex */
arrayindex++;
}
/* Wait for CCF flag to be set */
while (AES_GetFlagStatus(AES_FLAG_CCF) == RESET)
{}
/* Clear CCF flag */
AES_ClearFlag(AES_FLAG_CCF);
/* Init arrayindex */
arrayindex = 0;
/* read 16 times the DOUTR register to get the cipher text */
while (arrayindex < 16)
{
/* Reading MSB first */
CypherText[arrayindex] = AES_ReadSubData();
/* Increment arrayindex */
arrayindex++;
}
/* Disable the AES peripheral to change the operation mode */
AES_Cmd(DISABLE);
/* Select the key derivation and decryption mode */
AES_OperationModeConfig(AES_Operation_KeyDerivAndDecryp);
/* Re-enable the AES peripheral */
AES_Cmd(ENABLE);
/* Init arrayindex */
arrayindex = 0;
/* write 32 times in the DINR register with encryption key and cypher text */
while (arrayindex < 16)
{
/* writing MSB first */
AES_WriteSubKey(EncryptionKey[arrayindex]);
AES_WriteSubData(CypherText[arrayindex]);
/* Increment arrayindex */
arrayindex++;
}
/* Wait for CCF flag to be set */
while (AES_GetFlagStatus(AES_FLAG_CCF) == RESET)
{}
/* Clear CCF flag */
AES_ClearFlag(AES_FLAG_CCF);
/* Init arrayindex */
arrayindex = 0;
/* read 16 times the DOUTR register to get the computed plain text */
while (arrayindex < 16)
{
/* Reading MSB first */
ComputedPlainText[arrayindex] = AES_ReadSubData();
/* Increment arrayindex */
arrayindex++;
}
/* Check if decrypted cypher text match the original plain text */
cryptostatus = Buffercmp(PlainText, ComputedPlainText, 16);
if (cryptostatus == SUCCESS)
{
/* Turn on LD1 */
STM_EVAL_LEDOn(LED1);
}
else
{
/* Turn on LD3 */
STM_EVAL_LEDOn(LED3);
}
/* Infinite loop */
while (1)
{}
}