[NIIBE Yutaka] STM32F103 flash ROM read-out service

[NdK]

Il 07/06/2018 14:35, NIIBE Yutaka ha scritto:

> IMNSHO, those certification assume (and allow) proprietary technology.
> And evaluation for certification is too rough (for me).
> For example, many side channel attacks have been invented.
Yes, certifications can only state that the known attacks won't work.
They can't say anything about new ones. Can't be different.
When you buy a strong door, they can certify that the lock can't be
forced with known methods. But usually don't say anything about the
window left open :)

> BTW, I know a company in Japan which offers a service to decap a IC chip
> and to repair somthing by FIB in two days.  I don't know how much does
> it cost.  If the read-out from flash method to STM32F103 is modifying
> protection bit and simply use JTAG/SWD debugger, it takes two days +
> some.
The best we can do is keep that as a baseline. It requires 2 days? OK.
If my GnuK token disappears for more than 24h I know I have to revoke my
keys before they can crack KDF. That's a big plus against keys stored on
disk because I can see that the token is actually missing (say because I
have to use it every day): they physically need it to carry out the attack.
That's more or less the same thing I'm studying for my domotic system:
if a node goes offline for more than 'x' minutes, it's considered
captured and kicked out.
I think there's no other way (in my case, with ESP8266, it's even worse:
it can be read in a couple of minutes).

BYtE,
 Diego