stm32-crc

stm32-crc writes a CRC32 (STM32-flavored) checksum to the last 4 bytes of a .bin file.

Why?

I was reverse engineering the firmware of an STM32-based device and found out that its firmware was checksummed by using the last 4 bytes of the .bin file for a CRC32 checksum. But using a CRC32 algorithm that is quite a bit different from the standard one (see here).

Do I need this?

Probably not. I'm not even sure if this is done across most STM32 controllers or if it's just this particular one that has a special bootloader. But if this is useful for you, that's great ^^

Usage

Run the stm32-crc executable with one of the following subcommands:

1. Update: Update the checksum of a file.

   stm32-crc update firmware.bin

2. Check: Verify if the checksum in a file is valid.

   stm32-crc check firmware.bin

3. Calculate: Calculate and print the checksum of a file to stdout.

   stm32-crc calculate firmware.bin