Is there a method of securing private keys (or any secure data come to that) that need to be stored within, say, flash memory that could be accessible via e.g. debug port or bootloader?
There is a mechanism for protecting the memory against reads through the debug port, but I don't know how secure/reliable this is. The device has a bootloader built in, and the application has a bootloader, either of which could be vulnerable to exploits, so storing the keys as plain text is a bad idea. I'm assuming some kind of encryption would be needed, but that leads to the problem of storing the encryption key itself. The application must be able to gain access to these keys at any time without requiring any kind of external password to be sent.
I've spent quite a long time googling this, but I'm not really getting anywhere. As always, I might just need to know a phrase to search for and the answer will be obvious.