Hi,
I'm using two STM32WLE5 LoRa as TX and RX and added AES-ECB Encryption with Hardware Accelerator in the TX side and receive and decrypt it in RX side with the same Key. Now I want to change the TX module and want to implement same logic of AES Encryption in the TX side. Is there any documentation on how that can be implemented in the C/Python code for sending the same data with different module?
I have used PyCryptodome Python library for sending the data with encryption but it didn't work as expected. So, Is there any other library or documentation for implementing Encryption by which Receiver can be able to decrypt as before?
Any insights or guidance would be greatly appreciated.
Thanks in Advance.
I have tested AES Encryption in the TX side and found that the encrypted data is not same as that mentioned in the https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-38a.pdf file. Is there any configuration mismatch for the encryption?
I have got the output as follows:
Actual Data:
6b c1 be e2 2e 40 9f 96 e9 3d 7e 11 73 93 17 2a
Encrypted Data:
7c 64 5e ae 8 8d 5b 97 10 bc 96 a9 9 35 e1 4b
Code is as follows:
CRYP_HandleTypeDef hcryp;
__ALIGN_BEGIN static const uint32_t pKeyAES[4] __ALIGN_END = {
0x2B7E1516,0x28AED2A6,0xABF71588,0x09CF4F3C};
/* AES init function */
void MX_AES_Init(void)
{
/* USER CODE BEGIN AES_Init 0 */
/* USER CODE END AES_Init 0 */
/* USER CODE BEGIN AES_Init 1 */
/* USER CODE END AES_Init 1 */
hcryp.Instance = AES;
hcryp.Init.DataType = CRYP_DATATYPE_32B;
hcryp.Init.KeySize = CRYP_KEYSIZE_128B;
hcryp.Init.pKey = (uint32_t *)pKeyAES;
hcryp.Init.Algorithm = CRYP_AES_ECB;
hcryp.Init.DataWidthUnit = CRYP_DATAWIDTHUNIT_BYTE;
hcryp.Init.HeaderWidthUnit = CRYP_HEADERWIDTHUNIT_BYTE;
hcryp.Init.KeyIVConfigSkip = CRYP_KEYIVCONFIG_ALWAYS;
if (HAL_CRYP_Init(&hcryp) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN AES_Init 2 */
/* USER CODE END AES_Init 2 */
}
Encryption Block:
APP_LOG(TS_OFF, VLEVEL_L, "Actual Data:\n");
for(int i=0; i< bytes_to_send + bytes_to_pad; i++){
APP_LOG(TS_OFF, VLEVEL_L, "%x ", Tx_Buffer[i]);
}
APP_LOG(TS_OFF, VLEVEL_L, "\n");
status = HAL_CRYP_Encrypt(&hcryp, (uint32_t*)Tx_Buffer, (bytes_to_send + bytes_to_pad), (uint32_t*)Tx_Buffer_enc, 10);
APP_LOG(TS_OFF, VLEVEL_L, "Encryptrd Data:\n");
for(int i=0; i< bytes_to_send + bytes_to_pad; i++){
APP_LOG(TS_OFF, VLEVEL_L, "%x ", Tx_Buffer_enc[i]);
}
APP_LOG(TS_OFF, VLEVEL_L, "\n");
Do I need to change any configuration in AES Encryption to work as expected?
