/**
******************************************************************************
* @file stm32f4xx_cryp_aes.c
* @author MCD Application Team
* @version V1.0.0
* @date 30-September-2011
* @brief This file provides high level functions to encrypt and decrypt an
* input message using AES in ECB/CBC/CTR modes.
* It uses the stm32f4xx_cryp.c/.h drivers to access the STM32F4xx CRYP
* peripheral.
*
* @verbatim
*
* ===================================================================
* How to use this driver
* ===================================================================
* 1. Enable The CRYP controller clock using
* RCC_AHB2PeriphClockCmd(RCC_AHB2Periph_CRYP, ENABLE); function.
*
* 2. Encrypt and decrypt using AES in ECB Mode using CRYP_AES_ECB()
* function.
*
* 3. Encrypt and decrypt using AES in CBC Mode using CRYP_AES_CBC()
* function.
*
* 4. Encrypt and decrypt using AES in CTR Mode using CRYP_AES_CTR()
* function.
*
* @endverbatim
*
******************************************************************************
* @attention
*
* THE PRESENT FIRMWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS
* WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE
* TIME. AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY
* DIRECT, INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING
* FROM THE CONTENT OF SUCH FIRMWARE AND/OR THE USE MADE BY CUSTOMERS OF THE
* CODING INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.
*
*
© COPYRIGHT 2011 STMicroelectronics
******************************************************************************
*/
/* Includes ------------------------------------------------------------------*/
#include "stm32f4xx_cryp.h"
/** @addtogroup STM32F4xx_StdPeriph_Driver
* @{
*/
/** @defgroup CRYP
* @brief CRYP driver modules
* @{
*/
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
#define AESBUSY_TIMEOUT ((uint32_t) 0x00010000)
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/
/* Private functions ---------------------------------------------------------*/
/** @defgroup CRYP_Private_Functions
* @{
*/
/** @defgroup CRYP_Group6 High Level AES functions
* @brief High Level AES functions
*
@verbatim
===============================================================================
High Level AES functions
===============================================================================
@endverbatim
* @{
*/
/**
* @brief Encrypt and decrypt using AES in ECB Mode
* @param Mode: encryption or decryption Mode.
* This parameter can be one of the following values:
* @arg MODE_ENCRYPT: Encryption
* @arg MODE_DECRYPT: Decryption
* @param Key: Key used for AES algorithm.
* @param Keysize: length of the Key, must be a 128, 192 or 256.
* @param Input: pointer to the Input buffer.
* @param Ilength: length of the Input buffer, must be a multiple of 16.
* @param Output: pointer to the returned buffer.
* @retval An ErrorStatus enumeration value:
* - SUCCESS: Operation done
* - ERROR: Operation failed
*/
ErrorStatus CRYP_AES_ECB(uint8_t Mode, uint8_t* Key, uint16_t Keysize,
uint8_t* Input, uint32_t Ilength, uint8_t* Output)
{
CRYP_InitTypeDef AES_CRYP_InitStructure;
CRYP_KeyInitTypeDef AES_CRYP_KeyInitStructure;
__IO uint32_t counter = 0;
uint32_t busystatus = 0;
ErrorStatus status = SUCCESS;
uint32_t keyaddr = (uint32_t)Key;
uint32_t inputaddr = (uint32_t)Input;
uint32_t outputaddr = (uint32_t)Output;
uint32_t i = 0;
/* Crypto structures initialisation*/
CRYP_KeyStructInit(&AES_CRYP_KeyInitStructure);
switch(Keysize)
{
case 128:
AES_CRYP_InitStructure.CRYP_KeySize = CRYP_KeySize_128b;
AES_CRYP_KeyInitStructure.CRYP_Key2Left = __REV(*(uint32_t*)(keyaddr));
keyaddr+=4;
AES_CRYP_KeyInitStructure.CRYP_Key2Right= __REV(*(uint32_t*)(keyaddr));
keyaddr+=4;
AES_CRYP_KeyInitStructure.CRYP_Key3Left = __REV(*(uint32_t*)(keyaddr));
keyaddr+=4;
AES_CRYP_KeyInitStructure.CRYP_Key3Right= __REV(*(uint32_t*)(keyaddr));
break;
case 192:
AES_CRYP_InitStructure.CRYP_KeySize = CRYP_KeySize_192b;
AES_CRYP_KeyInitStructure.CRYP_Key1Left = __REV(*(uint32_t*)(keyaddr));
keyaddr+=4;
AES_CRYP_KeyInitStructure.CRYP_Key1Right= __REV(*(uint32_t*)(keyaddr));
keyaddr+=4;
AES_CRYP_KeyInitStructure.CRYP_Key2Left = __REV(*(uint32_t*)(keyaddr));
keyaddr+=4;
AES_CRYP_KeyInitStructure.CRYP_Key2Right= __REV(*(uint32_t*)(keyaddr));
keyaddr+=4;
AES_CRYP_KeyInitStructure.CRYP_Key3Left = __REV(*(uint32_t*)(keyaddr));
keyaddr+=4;
AES_CRYP_KeyInitStructure.CRYP_Key3Right= __REV(*(uint32_t*)(keyaddr));
break;
case 256:
AES_CRYP_InitStructure.CRYP_KeySize = CRYP_KeySize_256b;
AES_CRYP_KeyInitStructure.CRYP_Key0Left = __REV(*(uint32_t*)(keyaddr));
keyaddr+=4;
AES_CRYP_KeyInitStructure.CRYP_Key0Right= __REV(*(uint32_t*)(keyaddr));
keyaddr+=4;
AES_CRYP_KeyInitStructure.CRYP_Key1Left = __REV(*(uint32_t*)(keyaddr));
keyaddr+=4;
AES_CRYP_KeyInitStructure.CRYP_Key1Right= __REV(*(uint32_t*)(keyaddr));
keyaddr+=4;
AES_CRYP_KeyInitStructure.CRYP_Key2Left = __REV(*(uint32_t*)(keyaddr));
keyaddr+=4;
AES_CRYP_KeyInitStructure.CRYP_Key2Right= __REV(*(uint32_t*)(keyaddr));
keyaddr+=4;
AES_CRYP_KeyInitStructure.CRYP_Key3Left = __REV(*(uint32_t*)(keyaddr));
keyaddr+=4;
AES_CRYP_KeyInitStructure.CRYP_Key3Right= __REV(*(uint32_t*)(keyaddr));
break;
default:
break;
}
/*------------------ AES Decryption ------------------*/
if(Mode == MODE_DECRYPT) /* AES decryption */
{
/* Flush IN/OUT FIFOs */
CRYP_FIFOFlush();
/* Crypto Init for Key preparation for decryption process */
AES_CRYP_InitStructure.CRYP_AlgoDir = CRYP_AlgoDir_Decrypt;
AES_CRYP_InitStructure.CRYP_AlgoMode = CRYP_AlgoMode_AES_Key;
AES_CRYP_InitStructure.CRYP_DataType = CRYP_DataType_32b;
CRYP_Init(&AES_CRYP_InitStructure);
/* Key Initialisation */
CRYP_KeyInit(&AES_CRYP_KeyInitStructure);
/* Enable Crypto processor */
CRYP_Cmd(ENABLE);
/* wait until the Busy flag is RESET */
do
{
busystatus = CRYP_GetFlagStatus(CRYP_FLAG_BUSY);
counter++;
}while ((counter != AESBUSY_TIMEOUT) && (busystatus != RESET));
if (busystatus != RESET)
{
status = ERROR;
}
else
{
/* Crypto Init for decryption process */
AES_CRYP_InitStructure.CRYP_AlgoDir = CRYP_AlgoDir_Decrypt;
}
}
/*------------------ AES Encryption ------------------*/
else /* AES encryption */
{
CRYP_KeyInit(&AES_CRYP_KeyInitStructure);
/* Crypto Init for Encryption process */
AES_CRYP_InitStructure.CRYP_AlgoDir = CRYP_AlgoDir_Encrypt;
}
AES_CRYP_InitStructure.CRYP_AlgoMode = CRYP_AlgoMode_AES_ECB;
AES_CRYP_InitStructure.CRYP_DataType = CRYP_DataType_8b;
CRYP_Init(&AES_CRYP_InitStructure);
/* Flush IN/OUT FIFOs */
CRYP_FIFOFlush();
/* Enable Crypto processor */
CRYP_Cmd(ENABLE);
for(i=0; ((i