HMAC digest doesn't match expected (STM3221G-EVAL)

[OOmen]

I just purchased the STM3221G-EVAL board and I am working through some examples. I am currently using running the HMAC example and it runs fine. However I am unable to get the HMAC to match the test vectors provided in the specification (https://tools.ietf.org/html/rfc2202).

Specifically for the following:

test_case = 1

key = 0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b

key_len = 20

data = "Hi There"

data_len = 8

digest = 0xb617318655057264e28bc0b6fb378c8ef146be00

But I get a completely different digest.

Any ideas?

Many thanks in advance.

[After Forever]

> Any ideas?

I don't think so, at least not until you show us your code which doesn't work as expected :)

[OOmen]

Thanks [After Forever] - that was just a "hello world"

Here is the code:

/**
 ******************************************************************************
 * @file HASH/HASH_HMAC_SHA1MD5/Src/main.c 
 * @author MCD Application Team
 * @brief This example provides a short description of HASH digest calculation
 * using SHA1 and MD5 example.
 ******************************************************************************
 * @attention
 *
 * <h2><center>&copy; COPYRIGHT(c) 2017 STMicroelectronics</center></h2>
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 * 1. Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 * 3. Neither the name of STMicroelectronics nor the names of its contributors
 * may be used to endorse or promote products derived from this software
 * without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 ******************************************************************************
 */
 
/* Includes ------------------------------------------------------------------*/
#include "main.h"
 
/** @addtogroup STM32F2xx_HAL_Examples
 * @{
 */
 
/** @addtogroup HMAC_SHA1_MD5
 * @{
 */ 
 
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* HASH handler declaration */
HASH_HandleTypeDef HashHandle;
 
/* 
 "The hash processor is a fully compliant implementation of the secure
 hash algorithm (SHA-1), the MD5 (message-digest algorithm 5) hash 
 algorithm and the HMAC (keyed-hash message authentication code)
 algorithm suitable for a variety of applications.*** STM32 ***"
*/
 
 
#define cINPUT_TAB_SIZE ((uint32_t) 8)/* The size of the input data "cInput" */
#define cKEY_TAB_SIZE ((uint32_t) 20)
 
// hex for "Hi There"
__ALIGN_BEGIN const uint8_t cInput[cINPUT_TAB_SIZE] __ALIGN_END = {0x48, 0x69, 0x20, 0x54, 0x68, 0x65, 0x72, 0x65};
 
__ALIGN_BEGIN const uint8_t cKey[cKEY_TAB_SIZE] __ALIGN_END = {,
 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 
 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0xb0, 
 0xb0, 0xb0, 0xb0, 0x0b};
 
 
 
__ALIGN_BEGIN static uint8_t cSHA1Digest[20] __ALIGN_END;
__ALIGN_BEGIN static uint8_t cExpectSHA1Digest[20] __ALIGN_END = {0xb6, 0x17, 0x31, 0x86, 0x55, 0x05, 0x72, 0x64, 
 0xe2, 0x8b, 0xc0, 0xb6, 0xfb, 0x37, 0x8c, 0x8e, 
 0xf1, 0x46, 0xbe, 0x00};
/* Private function prototypes -----------------------------------------------*/
static void SystemClock_Config(void);
static void Error_Handler(void);
 
/* Private functions ---------------------------------------------------------*/
 
/**
 * @brief Main program
 * @param None
 * @retval None
 */
int main(void)
{
 /* STM32F2xx HAL library initialization:
 - Configure the Flash prefetch, instruction and Data caches
 - Configure the Systick to generate an interrupt each 1 msec
 - Set NVIC Group Priority to 4
 - Global MSP (MCU Support Package) initialization
 */
 HAL_Init();
 
 /* Configure the system clock to 120 MHz */
 SystemClock_Config();
 
 /* Configure LED1, LED3 and LED4 */
 BSP_LED_Init(LED1);
 BSP_LED_Init(LED3);
 BSP_LED_Init(LED4);
 /****************************************************************************/
 /*************************** HMAC-SHA1 2 ************************************/
 /****************************************************************************/
 BSP_LED_Off(LED1); 
 HAL_HASH_DeInit(&HashHandle);
 HashHandle.Init.DataType = HASH_DATATYPE_8B;
 HashHandle.Init.pKey = (uint8_t*)cKey;
 HashHandle.Init.KeySize = cKEY_TAB_SIZE;
 
 if(HAL_HASH_Init(&HashHandle) != HAL_OK)
 {
 Error_Handler();
 }
 
 /* Compute HMAC-SHA1 */
 if(HAL_HMAC_SHA1_Start(&HashHandle, (uint8_t*)cInput, cINPUT_TAB_SIZE, cSHA1Digest, 0xFF) != HAL_OK)
 {
 Error_Handler();
 }
 /* Compare computed digest with expected one */
 if(memcmp(cSHA1Digest, cExpectSHA1Digest, sizeof(cExpectSHA1Digest)/sizeof(cExpectSHA1Digest[0])) != 0)
 {
 Error_Handler();
 }
 else
 {
 BSP_LED_On(LED1);
 }
 
/****************************************************************************/
 /*************************** HMAC-SHA1 2 repeat *****************************/
 /****************************************************************************/
 BSP_LED_Off(LED1); 
 HAL_HASH_DeInit(&HashHandle);
 HashHandle.Init.DataType = HASH_DATATYPE_8B;
 HashHandle.Init.pKey = (uint8_t*)cKey;
 HashHandle.Init.KeySize = cKEY_TAB_SIZE;
 
 if(HAL_HASH_Init(&HashHandle) != HAL_OK)
 {
 Error_Handler();
 }
 
 /* Compute HMAC-SHA1 */
 if(HAL_HMAC_SHA1_Start(&HashHandle, (uint8_t*)cInput, cINPUT_TAB_SIZE, cSHA1Digest, 0xFF) != HAL_OK)
 {
 Error_Handler();
 }
 /* Compare computed digest with expected one */
 if(memcmp(cSHA1Digest, cExpectSHA1Digest, sizeof(cExpectSHA1Digest)/sizeof(cExpectSHA1Digest[0])) != 0)
 {
 Error_Handler();
 }
 else
 {
 BSP_LED_On(LED1);
 }
 
}
 
/**
 * @brief System Clock Configuration
 * The system Clock is configured as follow : 
 * System Clock source = PLL (HSE)
 * SYSCLK(Hz) = 120000000
 * HCLK(Hz) = 120000000
 * AHB Prescaler = 1
 * APB1 Prescaler = 4
 * APB2 Prescaler = 2
 * HSE Frequency(Hz) = 25000000
 * PLL_M = 25
 * PLL_N = 240
 * PLL_P = 2
 * PLL_Q = 5
 * VDD(V) = 3.3
 * Flash Latency(WS) = 3
 * @param None
 * @retval None
 */
static void SystemClock_Config(void)
{
 RCC_ClkInitTypeDef RCC_ClkInitStruct;
 RCC_OscInitTypeDef RCC_OscInitStruct;
 
 /* Enable HSE Oscillator and activate PLL with HSE as source */
 RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
 RCC_OscInitStruct.HSEState = RCC_HSE_ON;
 RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
 RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
 RCC_OscInitStruct.PLL.PLLM = 25;
 RCC_OscInitStruct.PLL.PLLN = 240;
 RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
 RCC_OscInitStruct.PLL.PLLQ = 5;
 if(HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
 {
 Error_Handler();
 }
 
 /* Select PLL as system clock source and configure the HCLK, PCLK1 and PCLK2 
 clocks dividers */
 RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2);
 RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
 RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
 RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV4;
 RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2;
 if(HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_3) != HAL_OK)
 {
 Error_Handler();
 }
}
 
/**
 * @brief This function is executed in case of error occurrence.
 * @param None
 * @retval None
 */
static void Error_Handler(void)
{
 /* Turn LED3 on */
 BSP_LED_On(LED3);
 while(1)
 {
 }
}
 
#ifdef USE_FULL_ASSERT
/**
 * @brief Reports the name of the source file and the source line number
 * where the assert_param error has occurred.
 * @param file: pointer to the source file name
 * @param line: assert_param error line source number
 * @retval None
 */
void assert_failed(uint8_t* file, uint32_t line)
{ 
 /* User can add his own implementation to report the file name and line number,
 ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
 
 /* Infinite loop */
 while (1)
 {
 }
}
#endif
 
/**
 * @}
 */ 
 
/**
 * @}
 */ 
 
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/

[After Forever]

Now compare the key you mentioned and the key you wrote:

0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b

0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0bb0b0b0b00b

[OOmen]

Aha - thanks.

Fixed it but still no match.

__ALIGN_BEGIN const uint8_t cInput[cINPUT_TAB_SIZE] __ALIGN_END = {0x48, 0x69, 0x20, 0x54, 0x68, 0x65, 0x72, 0x65};

__ALIGN_BEGIN const uint8_t cKey[cKEY_TAB_SIZE] __ALIGN_END =   {0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 

                                  0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 

                                  0x0b, 0x0b, 0x0b, 0x0b};

[OOmen]

Here is what I get:

0x75733ACAE127DD1DBFB2F8156E6A6E0C650B94B2