How to know if the MASTER_ECU key has been loaded

[warai]

I have this code that loads the MASTER_ECU key and flash keys every time the system boots. I don't want to do that. Is there a register where a status bit is set to let me check whether I have all the keys loaded already? Note that I don't erase the keys.

[nevozade]

Hello @lukaszadrapa ,

Is there any way to verify if the KEY_<n>s are using (have value) or empty by checking a register or smth else? (not for MASTER_ECU_KEY, I am asking for KEY_n such as CSE_KEY_4, CSE_KEY_5, .. etc.). I do not desire to learn the content, just want to know if it was loaded before, or not?

Regards,

Nevzat.

[lukaszadrapa]

Hi,

as per your description, it seems that you have the keys included in your application image, am I right? This is not common solution, it inserts significant security risk. Initial configuration of the CSE should be done in a factory, your keys shouldn't be stored in normal flash.

To answer your question - there's no such status bit. The only option I can see is to try to use a key and check if error "key empty" is returned. But as mentioned above, I wouldn't do that in this way.

Regards,

Lukas

[warai]

Thanks Lukas!

I will separate the loading of keys to the actual decryption. I am actually using the CSE module to perform decryption of received image.