Hello,
I would like to use the X-CUBE-CRYPTOLIB to calculate a SHA256 with a key. My implementation or the example HMAC_SHA2_AuthenticateVerify works in STM32CubeIDE 1.13.1 for an STM32L432KCU microcontroller.
Source: https://www.st.com/en/embedded-software/x-cube-cryptolib.html
To rule out the possibility that the example project has implemented something that I forgot to copy into Atollic Studio, I created a new project in STM32CubeIDE and integrated the X-CUBE-CRYPTOLIB there as I did in Atollic Studio. The hash was calculated correctly there.
Now my problem:
The development environment Atollic TrueSTUDIO for STM32 9.3.0 is used for an existing project. I would like to use the X-CUBE-CRYPTOLIB there. If I put the "simple" example there, then the hash is calculated incorrectly.
The error occurs on the line if (memcmp(Expected_Tag, Computed_Tag, computed_size) != 0) because the Computed_Tag was not calculated correctly.
What could be the reason?
/* Initialize cryptographic library */
if (cmox_initialize(NULL) != CMOX_INIT_SUCCESS)
{
Error_Handler();
}
/* --------------------------------------------------------------------------
* SINGLE CALL USAGE
* --------------------------------------------------------------------------
*/
/* Compute directly the authentication tag passing all the needed parameters */
retval = cmox_mac_compute(CMOX_HMAC_SHA256_ALGO, /* Use HMAC SHA256 algorithm */
Message, sizeof(Message), /* Message to authenticate */
Key, sizeof(Key), /* HMAC Key to use */
NULL, 0, /* Custom data */
Computed_Tag, /* Data buffer to receive generated authnetication tag */
sizeof(Expected_Tag), /* Expected authentication tag size */
&computed_size); /* Generated tag size */
/* Verify API returned value */
if (retval != CMOX_MAC_SUCCESS)
{
Error_Handler();
}
/* Verify generated data size is the expected one */
if (computed_size != sizeof(Expected_Tag))
{
Error_Handler();
}
/* Verify generated data are the expected ones */
if (memcmp(Expected_Tag, Computed_Tag, computed_size) != 0)
{
Error_Handler();
}
/* Verify directly the message passing all the needed parameters */
retval = cmox_mac_verify(CMOX_HMAC_SHA256_ALGO, /* Use HMAC SHA256 algorithm */
Message, sizeof(Message), /* Message to authenticate */
Key, sizeof(Key), /* HMAC Key to use */
NULL, 0, /* Custom data */
Expected_Tag, /* Authentication tag */
sizeof(Expected_Tag)); /* tag size */
/* Verify API returned value */
if (retval != CMOX_MAC_AUTH_SUCCESS)
{
Error_Handler();
}
computed
