STM32F415 Hardware Crypto

JSE · February 12, 2021, 5:22pm

Hello,

I’ve read that the STM32F415 has a built-in hardware crypto module for AES, and found a limited description of it here: https://rtfm.newae.com/Targets/UFO%20Targets/CW308T-STM32F/#hardware-aes.

“To use the hardware crypto, call HW_AES128_Init() at the beginning of your program. You can update the key with HW_AES128_LoadKey(), encrypt plaintext with HW_AES128_Enc(), and decrypt data with HW_AES128_Dec().”

Is there a working example of this available somewhere that someone could point me to that works with the ChipWhisperer?

Alex_Dewar · February 12, 2021, 5:29pm

You can just use the typical AES calls with ChipWhisperer, but instead of CRYPTO_TARGET=TINYAES128C, use CRYPTO_TARGET=HWAES. We actually have a tutorial that does an attack on the STM32F4 HWAES:

github.com

newaetech/chipwhisperer-jupyter/blob/master/courses/sca201/SOLN_Lab 2_2 - CPA on Hardware AES Implementation.ipynb

{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Topic 2, Part 2 - CPA on Hardware AES Implementation"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "---\n",
    "NOTE: This lab references some (commercial) training material on [ChipWhisperer.io](https://www.ChipWhisperer.io). You can freely execute and use the lab per the open-source license (including using it in your own courses if you distribute similarly), but you must maintain notice about this source location. Consider joining our training course to enjoy the full experience.\n",
    "\n",
    "---"
   ]
  },
  {

This file has been truncated. show original

github.com

newaetech/chipwhisperer-jupyter/blob/master/courses/sca201/Lab 2_2 - CPA on Hardware AES Implementation (HARDWARE).ipynb

{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Topic 2, Part 2 - CPA on Hardware AES Implementation"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "---\n",
    "NOTE: This lab references some (commercial) training material on [ChipWhisperer.io](https://www.ChipWhisperer.io). You can freely execute and use the lab per the open-source license (including using it in your own courses if you distribute similarly), but you must maintain notice about this source location. Consider joining our training course to enjoy the full experience.\n",
    "\n",
    "---"
   ]
  },
  {

This file has been truncated. show original

Alex

JSE · February 12, 2021, 5:38pm

Oh awesome. Thank you Alex!

JSE · February 24, 2021, 8:23pm

Hello again. Do you know if this hardware implementation is masked or unmasked? I’d be curious to know if the provided hardware implementation for the CW305 FPGA is as well.

jmichel · February 24, 2021, 11:08pm

STM32F415 uses unmasked AES for its hardware accelerator.
If you want a hardware masked AES, you can try the K82F target for example.

JSE · February 25, 2021, 12:07am

Okay great, thank you.

jpthibault · February 25, 2021, 2:48pm

The example CW305 AES implementation isn’t masked.