Bootloader with decryption, but which utility can I use to encrypt my firmware

[clemente]

Posted on July 30, 2016 at 17:49

Hello to all, I'm realizing a bootloader with AES decryption. I'm using the ''STM32CubeExpansion_Crypto_V3.1.0'' library to decrypt the file. Which PC software can I use to encrypt the firmware?

I'm using AES128 bit, I tried to encrypt with openssl, but the generated encrypted file is not ''compatible''.

#stm32l4-bootloader-decryption

[Tesla DeLorean]

Posted on July 31, 2016 at 02:12

There is a pretty strong relationship between the parameters to encrypt/decrypt, the AES algorithms are readily available in C, you could presumably build something using fopen/fread/fwrite/fclose to read and convert data in exactly the manner you need.

You'd need to define precisely the data you are encrypting, and the keys and initialization vector in use.

In terms of validating what you are doing, you'd want to demonstrate encryption and decryption of your data stream on a PC, and then demonstrate the same decryption on the STM32 to show you can get back to the data you put in, and you get it in a form you can use.

You should also be able to take the library test examples and replicate them in your own code on a PC.